Intense New England Hurricanes Much More Numerous 340 to 1800 Years Ago

By: Jeff Masters , 6:43 PM GMT on February 17, 2015

Numerous Category 3 and 4 hurricanes frequently pounded New England during the first millennium, from the peak of the Roman Empire into the height of the Middle Ages, said a study accepted for publication this month in the open-access journal Earth’s Future, Climate Forcing of Unprecedented Intense-Hurricane Activity in the Last 2,000 Years. These prehistoric hurricanes were stronger than any hurricane documented to hit the region since the mid-1800s, and would be catastrophic if they hit the region today, according to Jeff Donnelly, a scientist at Woods Hole Oceanographic Institution (WHOI) in Massachusetts and lead author of the new paper. In a press release, Donnelly said, “We hope this study broadens our sense of what is possible and what we should expect in a warmer climate. We may need to begin planning for a category 3 hurricane landfall every decade or so rather than every 100 or 200 years.”


Figure 1. The storm surge from Category 2 Hurricane Carol in 1954 batters New England's Edgewood Yacht Club near Providence, Rhode Island. Image credit: NOAA Photo Library.

The paper is the latest contribution to the field of paleotempestology--the study of past tropical cyclone activity by means sediment deposits, cave speleothems, tree rings, coral deposits, as well as historical documentary records. In this case, the researchers took sediment cores from Salt Pond near Falmouth on Cape Cod, Massachusetts. The pond is separated from the ocean by a 1.3- to 1.8-meter (4.3- to 5.9-foot) high sand barrier. Over hundreds of years, storm surges from Category 2 and stronger hurricanes have deposited sediment over the barrier and into the pond. The scientists were able to calibrate the timing of the intense hurricane strikes by dating the layers from Category 2 Hurricane Bob of 1991, the 1675 (September 7) New England hurricane, and the Great Colonial Hurricane of 1635, which passed across southeastern New England and caused widespread damage consistent with a category 3 hurricane.


Figure 2. Scientists collect a sediment core from Salt Pond in Falmouth, Massachusetts, to study hurricane overwash deposits placed there by storm surges from intense hurricanes. The aluminum tube was vibrated into the muddy sediment at the bottom of the pond and then extracted with a hoist. Image Credit: WHOI

The prehistoric sediments showed that there were two periods of elevated intense hurricane activity on Cape Cod--from 150 to 1150, and from 1400 to 1675. Previous paleotempestology studies also found evidence of high hurricane activity during 150 - 1150 A.D. from the Caribbean to the Gulf Coast. Both time periods had unusually warm sea surface temperatures (SSTs) in the Main Development Region for hurricanes, from the Caribbean to the coast of Africa. Warm ocean temperatures in this region have been linked to increased intense hurricane activity by a number of recent research papers. In recent decades, ocean temperatures in the Main Development Region have surpassed the warmth of prehistoric levels, and these waters are expected to warm further over the next century as the climate heats up, suggesting that intense hurricane activity in New England may return to the levels of 340 to 1800 years ago. However, other factors besides warming SSTs will also shape what happens in the North Atlantic. For example, the pattern of ocean warming could bring more El Niño-style wind shear to the Atlantic, reducing hurricane activity. Still, New England would be wise to take heed of Donnelly's advice that we may need to begin planning for a category 3 hurricane landfall every decade or so rather than every 100 or 200 years.

Jeff Masters


The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 86 - 36

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10Blog Index

Quoting 68. sar2401:

I decided I wasn't going to plop down $35.95 for that one either, especially since a Happy Meal is a big deal for me now. :-) The abstract did get me thinking about about some of the huge Nor'easters we've had just since I've been around and how you go about distinguishing them from cat 2 plus hurricanes. Since it appears the Donnelly study couldn't resolve time periods down to a year, let alone seasons, it would seem logical that some sediments were the result of non-tropical storms. I didn't see that topic addressed specifically in the study.

See post#83 - extratropical storms were addressed.
Member Since: December 31, 1969 Posts: Comments:
Both the European and Canadian model suggest the possibility of a quick thump of accumulating snow Saturday afternoon and evening before precipitation changes to ice and then rain.This is just a quick and early look at this possible storm system and there is ample time for the details to change and perhaps change radically. We’ll keep you informed with daily updates.
Member Since: December 31, 1969 Posts: Comments:
Cyclone Lam expected to make landfall as Coral Sea low tracks towards the Queensland coast
Brian Williams, The Courier-Mail, February 18, 2015 12:00AM
Parts of Brisbane and the Gold and Sunshine coasts could receive up to 400mm of rain for the three days from tomorrow as a Coral Sea low tracks towards the coast.
Flash flooding is expected, with the low an even money bet to form into a cyclone.
It comes as Cyclone Lam in the Gulf of Carpentaria is expected to muscle up into a category 4 tropical storm, the second most powerful. It will be the first cyclone to cross the coast this season, after Bakung and Kate veered away.
Only two previous cyclone seasons in the past 50 years have seen the first coastal crossing occur so late.
Winds from Cyclone Lam will reach about 170km/h today, accompanied by a storm surge and flooding. ...


Good night with this. Weather in Europe is calm, except some areas in the western and south-central Mediterranean (including the northern coast of Africa) and northwestern Turkey (hit by sea-effect snow). More at estofex.org.

Member Since: Posts: Comments:
Quoting 57. sar2401:

I've snipped some of your reply out since it's you, me, and about three other people here who really care about this kind of thing. :-) Let's just look at that one statement. Bob was the most intense hurricane to hit New England since, say, 1900? I don't think many of our hurricane trackers would agree. So, why Bob? The core sample picture showed the deposition from Bob, Carol, and the Long Island Hurricane of 1938. Carol was at least as intense as Bob, and the 1938 storm was much ore intense in terms of storm surge and deposition. Bob looked bigger and more impressive on the core but I assume that's because the deposition was more recent. We know for sure we have a 1938 storm that was more intense, you can see it in the core, so why choose Bob as your marker for historical storms?

I'm not saying this study is somehow fatally flawed. I don't know enough about this part of science to even make that judgement. I do know enough about study construction to ask some questions about why things were done in a certain way. What I would like to see is another team of paleotempestologists (is that a word?) get the same cores and run the same tests to see if they come up with the same answers. That's the way we replicated studies in biology and I don't see why it wouldn't apply here.

Quoting 71. Naga5000:


This is why Bob was used:

"3.12 Event Attribution

The most recently deposited coarse-grained event bed (#1) occurs at about 10 cm depth and based on our age model dates to between 1982 and 2005 CE at 95% confidence (Fig. 2b, c;Supplementary Fig. 6). This event bed was likely deposited by Hurricane Bob in 1991 CE, the only category 2 or greater storm since 1851 CE [Landsea et al., 2004] to pass within 100 km to the west of Falmouth (Supplementary Fig. 4). Hurricane Bob passed about 60 km west of Salt Pond (Fig. 1b) with maximum sustained winds of 45 m/s, causing a storm tide ~1.6 m
above MHW in Falmouth [Boldt et al. , 2010] and maximum offshore wave heights of approximately 4 meters [Cheung et al., 2007]. Washover fans across the western portion of the barrier fronting Salt Pond evident in aerial photographs taken immediately following Hurricane Bob indicate overtopping by the combination of surge and wave runup (Supplementary Fig. 7). Historically, severe winter storms and tropical cyclones that either pass offshore or make landfall to the east have failed to produce storm tides capable of overtopping the barrier fronting Salt Pond (see supplemental material) [Boldt et al., 2010]. Conversely, hurricanes that made landfall further west than Bob in the middle part of the 20th century (e.g., 1938, 1944 CE) produced storm tides capable of overtopping the Salt Pond barrier [Boldt et al., 2010], yet these events did not leave coarse event bed in Salt Pond"

Bob is a great control storm to use for dating and landfall locations.

In addition to Naga's posted excerpt from the paper, these are two excerpts from the supporting information for the paper:

"Six additional extratropical storms resulted in storm tides between 0.9 and 1.05 m above MHW
at the Woods Hole gauge between 1932 and 1982 CE and like the extratropical storms of the
last few decades, none of these storms resulted in event beds in Salt Pond. A series of
hurricanes made landfall on Long Island, NY in the middle part of the 20th century (e.g., 1938,
1944, 1954 CE), and while Woods Hole experienced significant storm tides related to these
events [Boldt et al., 2010], none of these events appear to have left a distinguishable coarse
event bed in Salt Pond
."

"Historically extratropical storms have not generated sufficient storm tides and wave energy to
mobilize and transport coarse sediment to the depo-center at Salt Pond. Further, despite
generating enough surge to overtop the barrier fronting Salt Pond, more distal landfalling
severe historical hurricanes (i.e. 1938, 1944, 1954) with relatively weak local winds (perhaps
tropical storm force or marginal category one strength) failed to generate event beds in Salt
Pond
."

I don't see where either Carol for the Hurricane of 1938 are shown in the soil core graphs at all. From Figure S6a of the Supporting Information, and in Figures 2c and 3 of the paper, Bob is identified, as well as the two storms from the 1600s.

I'm much more at ease reading geological methods and studies than studies regarding meteorology, so we're kind of 'opposite' in that aspect, I guess. I have no qualms with the methodology used in this study as far as the identification of event beds are concerned.

The portion of the study that no one has really talked about in the blog is the AMM/MDR SST/migrating ITCZ aspect of paper (discussed in the Climatic Forcing and Conclusions and Implications sections). That's what I'm less knowledgeable about, and would love to see some discussion of this.
Member Since: December 31, 1969 Posts: Comments:
Several burst water pipes causing floods on Toronto streets
02/17/2015 07:10 AM Toronto staff
Roller-coaster temperatures in Toronto are creating havoc around the city, with many water pipes bursting.
Member Since: Posts: Comments:
An error with that is the last time ANY tropical cyclone hit New England was Bob in 1991, the rest were recurves off the east of Cape Cod/Nantucket, or Inland prior to hitting New England and maintained tropical storm winds into the region.
The idea that suddenly a Cat 3 will hit New England every 10 years is funny.
Member Since: Posts: Comments:
Quoting luvtogolf:


It was pretty heavy rain but brief. Your comment raised a question that I never really thought about. Is there criteria? We'll see if an expert answers.

Squall Line

A line of active thunderstorms, either continuous or with breaks, including contiguous precipitation areas resulting from the existence of the thunderstorms.

NWS definition. You can have rain in a squall line with no lightning or thunder as long as it's part of a line that does have lightning and thunder. Otherwise, it's just a line of showers. They can be intense showers, but not a squall line.
Member Since: December 31, 1969 Posts: Comments:
Northern Argentina floods kill at least six in Cordoba

The river overflowed after 32cm (12.6in) fell in the space of 12 hours, trapping people in their cars.

Link
Member Since: Posts: Comments:
Quoting 72. luvtogolf:



We got a brief but pretty heavy rain in Oldsmar. I know that Matt called this a squall line. I don't think it is because there was no lightning or strong winds. Is there criteria for a line to be officially called a squall line?


Yeah. I didn't mean to make it sound worse than it was. It was exactly as you described. A good solid downpour for a brief amount of time with no lightning. I have no idea whether there is criteria to call a line of storms a squall line. Good question for somebody else to answer.
Member Since: December 31, 1969 Posts: Comments:
A word about Forams , as a proxy.

There are over 10,000 Foraminifera both living (8,708) and fossil (1,837). Each one lives in it's own sweet spot of temperature, salinity , depth, etc, etc.

The Foraminifera fossil record dates back to the mid-Jurassic, and represents an unparalleled record for scientists testing and documenting the evolutionary process.

The number one users of this record are the oil companies.
Member Since: Posts: Comments:
Paleohurricane Science
By Andrew Alden
Long before 2005's Hurricane Katrina outdid all its American predecessors in damages, experts have warned that the United States is growing more vulnerable to extreme climate events. Part of planning for future disasters is finding out their patterns in the past. In the case of earthquakes, we have pursued this research - paleoseismology - for decades. For hurricanes and other storms, the corresponding research - paleotempestology - is just beginning. ...

Paleotempestology
Tuesday, May 6, 2014
This term is the core of UNC Charlotte professor Scott P. Hippensteel's research. Though it seems a complex word, if broken down, the meaning is simple. "Paleo" is the Greek derivation for "ancient" or "long ago". Tempest is defined as a storm, usually a violent one. "logy" is a Latin and Greek root meaning "a branch of science," or the specific study of something. Thus, paleotempestology means the study of ancient storms.
...

Through his studies of paleotempestology, Scott Hippensteel thinks that he has found an answer, in a microorganism called foraminifers. Foraminifers are an aquatic microorganism that reside in the sediment of the sea bed. When they die, they leave small shells that can be traced through time. Think of foraminifer fossil deposits as a form of time capsule.
Foraminifers usually reside off of the shores of land masses. When a significant storm- say, a Level 5 hurricane- arrives, the power of the storm whips up the sediment on the sea bed and deposits it closer to the shore, in the bays and directly off of the land mass. They remain in this new location and, as Hippensteel has found, can be used as indicators of large hurricanes in the past.
...

Glad that I've met the foraminifera this evening :-) They look a bit like Christmas cookies, don't they?
Member Since: Posts: Comments:
Kate Matrosova, a New York resident and Wall Street trader, froze to death while attempting a solo hike of the Presidential Mountain Range in New Hampshire, over the weekend.

This reminds me of the fellow in Utah who had to cut his arm off , because he didn't tell anyone where he was going.
Member Since: Posts: Comments:
Quoting sar2401:
I read it also. It falls over from the first indicator storm. From the study "...the historical interval are consistent with severe hurricanes in 1991 (Bob)...". I don't know how they defined "severe" but Bob was not a cat 3 at landfall in Rhode Island and certainly was not a cat 3 when it moved over Salt Pond.
The study never states that Bob was a Cat 3 at landfall. It says Bob was "severe", and that is correct in every sense of the word: Bob's effects were indeed severe.
Quoting sar2401:
How do you start with Bob and use that to extrapolate to the other storms as being cat 3's.
The study didn't extrapolate from just those three storms. In fact, it explicitly states it didn't extrapolate at all, but rather based its findings on dozens of prehistoric events. (Abstract, paragraph 1)
Quoting sar2401:
In addition, the core samples came from one pond in Massachusetts. Again, from the study: "A shift in activity to the North American east coast occurred ca. 1400 CE, with more frequent severe hurricane strikes recorded from The Bahamas to New England between 1400 and 1675 CE." Now it includes the Bahamas? The whole East Coast? What? Based on what evidence?
The study clearly states that inferences to the spatial distribution of historical storms were based on not just Salt Pond, but also locations such as Lighthouse Bluehole in the Caribbean and Laguna Playa Grande in Puerto Rico. (3.2)
Quoting sar2401:
>Their own calculations for return rate ratio was based on the number of cat 2 plus hurricanes hitting New England based on the best track database over the past 162 years, not cat 3 plus. (Section 6.2, first paragraph). The occurrence of cat 3 plus events was, and is, so rare that there wouldn't have been enough of them to use for a reasonable base of calculation. Why then does Donnelly make the statement in the press release quoted above that the return rate of cat 3 plus hurricanes is going to increase when the study doesn't use that criteria?
I believe you mean section 2.6. If you read that entire section, you'll see the math the researchers used to derive their estimates. There's nothing tricky about that math, but the reader does need to be able to follow along to make complete sense of it.
Quoting sar2401:
I have lots of other questions about methodology and conclusions that don't make sense to me either. I saw nothing in the way they were able to resolve temporal distribution that would have excluded sedimentation deposition from a powerful Nor'easter rather than a tropical cyclone. I won't plow thorough them all here and have the blog want to kill me. At the very least, Donnelly, the lead researcher, is making statements for attribution that are clearly not supported by the study.
Neither the publishers nor the editors nor the author's nor the reviewers agree with you; they seem to agree that the paper is scientifically sound. That being said, however, you're certainly free to write up and submit for review an in-depth rebuttal. I think I speak for many of us when I say that we'd read it with an open mind...
Member Since: December 31, 1969 Posts: Comments:
Quoting 57. sar2401:

I've snipped some of your reply out since it's you, me, and about three other people here who really care about this kind of thing. :-) Let's just look at that one statement. Bob was the most intense hurricane to hit New England since, say, 1900? I don't think many of our hurricane trackers would agree. So, why Bob? The core sample picture showed the deposition from Bob, Carol, and the Long Island Hurricane of 1938. Carol was at least as intense as Bob, and the 1938 storm was much ore intense in terms of storm surge and deposition. Bob looked bigger and more impressive on the core but I assume that's because the deposition was more recent. We know for sure we have a 1938 storm that was more intense, you can see it in the core, so why choose Bob as your marker for historical storms?

I'm not saying this study is somehow fatally flawed. I don't know enough about this part of science to even make that judgement. I do know enough about study construction to ask some questions about why things were done in a certain way. What I would like to see is another team of paleotempestologists (is that a word?) get the same cores and run the same tests to see if they come up with the same answers. That's the way we replicated studies in biology and I don't see why it wouldn't apply here.

This is why Bob was used:

"3.12 Event Attribution

The most recently deposited coarse-grained event bed (#1) occurs at about 10 cm depth and based on our age model dates to between 1982 and 2005 CE at 95% confidence (Fig. 2b, c;Supplementary Fig. 6). This event bed was likely deposited by Hurricane Bob in 1991 CE, the only category 2 or greater storm since 1851 CE [Landsea et al., 2004] to pass within 100 km to the west of Falmouth (Supplementary Fig. 4). Hurricane Bob passed about 60 km west of Salt Pond (Fig. 1b) with maximum sustained winds of 45 m/s, causing a storm tide ~1.6 m
above MHW in Falmouth [Boldt et al. , 2010] and maximum offshore wave heights of approximately 4 meters [Cheung et al., 2007]. Washover fans across the western portion of the barrier fronting Salt Pond evident in aerial photographs taken immediately following Hurricane Bob indicate overtopping by the combination of surge and wave runup (Supplementary Fig. 7). Historically, severe winter storms and tropical cyclones that either pass offshore or make landfall to the east have failed to produce storm tides capable of overtopping the barrier fronting Salt Pond (see supplemental material) [Boldt et al., 2010]. Conversely, hurricanes that made landfall further west than Bob in the middle part of the 20th century (e.g., 1938, 1944 CE) produced storm tides capable of overtopping the Salt Pond barrier [Boldt et al., 2010], yet these events did not leave coarse event bed in Salt Pond"

Bob is a great control storm to use for dating and landfall locations.
Member Since: Posts: Comments:
Quoting LAbonbon:

busy snacking, will replace this w/ real reply when I get to the bottom of the popcorn bag :P
LOL. I should go off and do some real work too before my fiance wakes up from her night job and starts yelling. :-)
Member Since: December 31, 1969 Posts: Comments:
Just read the updated blog on the issue of the core samples and elevated hurricane activity from the Caribbean to the Gulf. Here is another interesting core study on the decline of the Maya in Central America based upon possible drought issues. Interesting that the 800 to 1000 AD time period also happens to fall within the very large period (150-1150) mentioned above. However, I don't know how far core samples can go in terms of accurately predicting the future:


In between 300 A.D. and 900 A.D. Mayans prospered through much of Central America and in Yacatan in Southern Mexico. It is said that there could be numerous causes for the disappearance, or the turn down of the Ancient Mayan Civilization.


Lake Chichancanab's in Mexico, meaning "Little sea" has helped us to understand a bit about the environment in the region where the Mayans lived. David Hodell, Mark Brenner, and Jason Curtis took core samples from Lake Chichancanab. The data from the core samples indicated significant meteorological changes during the same time that the Maya's life took a dramatic turn for the worse.


The geologists of the University of Florida needed the climate conditions around Lake Chichancanab to help answer their questions about the Mayas decline. The May 2000 expedition to Chichancanab was the second team that made it to the region. The 1993 samples helped the geologists determine that between 800 and 1000 A.D. was their driest draught in 7,000 years.

Member Since: December 31, 1969 Posts: Comments:
Quoting LAbonbon:

No, I didn't, but I did find the abstract for Mallinson (the Outer Banks research). You can read the study for $35.95 (!), but here's the abstract:

Abstract
The Outer Banks barrier islands of North Carolina, USA, contain a geologic record of inlet activity that extends from ca. 2200 cal yr BP to the present, and can be used as a proxy for storm activity. Optically stimulated luminescence (OSL) dating (26 samples) of inlet-fill and flood tide delta deposits, recognized in cores and geophysical data, provides the basis for understanding the chronology of storm impacts and comparison to other paleoclimate proxy data. OSL ages of historical inlet fill compare favorably to historical documentation of inlet activity, providing confidence in the technique. Comparison suggests that the Medieval Warm Period (MWP) and Little Ice Age (LIA) were both characterized by elevated storm conditions as indicated by much greater inlet activity relative to today. Given present understanding of atmospheric circulation patterns and sea-surface temperatures during the MWP and LIA, we suggest that increased inlet activity during the MWP responded to intensified hurricane impacts, while elevated inlet activity during the LIA was in response to increased nor'easter activity. A general decrease in storminess at mid-latitudes in the North Atlantic over the last 300 yr has allowed the system to evolve into a more continuous barrier with few inlets.
I decided I wasn't going to plop down $35.95 for that one either, especially since a Happy Meal is a big deal for me now. :-) The abstract did get me thinking about about some of the huge Nor'easters we've had just since I've been around and how you go about distinguishing them from cat 2 plus hurricanes. Since it appears the Donnelly study couldn't resolve time periods down to a year, let alone seasons, it would seem logical that some sediments were the result of non-tropical storms. I didn't see that topic addressed specifically in the study.
Member Since: December 31, 1969 Posts: Comments:
deleted
Member Since: December 31, 1969 Posts: Comments:
Tropical Cyclone Warning Center Brisbane
Tropical Cyclone Advice #1
TROPICAL LOW 14U
4:48 AM EST February 18 2015
========================================

At 4:00 AM EST, Tropical Low (997 hPa) located at 15.1S 155.9E or 970 kilometers northeast of Mackay and 1150 kilometers north northeast of Bundaberg has 10 minute sustained winds of 30 knots with gust of 45 knots. The tropical low is reported as moving east southeast at 4 knots.

Dvorak Intensity: T2.5/2.5/D1.0/24 HRS

A tropical low lies over the central Coral Sea. It is expected to shift towards the southwest during today and Thursday, possibly intensifying to a tropical cyclone before crossing the east Queensland coast between St Lawrence and Double Island Point early Friday.

The tropical low will result in significant impacts over east Queensland districts south of about St Lawrence regardless of whether or not it transitions to a tropical cyclone.

A separate Severe Weather Warning is current for areas south of Double Island Point and west to the Great Dividing Range.

GALES are expected to develop about coastal and island communities between St Lawrence and Double Island Point during Thursday evening.

Heavy rainfall will develop about coastal and island communities between St Lawrence and Double Island Point during Thursday, particularly over areas to the south of the system. A Flood Watch is current for the area.

Abnormally high tides will be experienced as the system approaches the coast. Water levels are expected to rise above the highest tide of the year on the high tide on Thursday.

Dangerous surf is expected to develop about exposed beaches south of Sandy Cape from early Thursday.

Forecast and Intensity
====================
12 HRS 17.1S 155.5E - 30 knots (Tropical Low)
24 HRS 19.1S 153.7E - 30 knots (Tropical Low)
48 HRS 23.3S 151.0E - 40 knots (CAT 1) nearby Gladstone
72 HRS 28.0S 152.5E - 30 knots (Tropical Low)

Additional Information
===================
Convection has increased significantly during the last 24 hours, with the system showing a clear intensifying trend despite the presence of moderate to strong easterly wind shear suggested by the 12UTC CIMSS winds.

Location of the low level circulation center has been difficult due to a dearth of proximal observations. 12UTC ASCAT suggested a small area of gales in at least the western quadrant. The system exhibits a uniform CDO on IR satellite imagery. Applying the Central Cold Cover rule gives DT 2.5. MET and PAT agree, so final T and CI are 2.5.

The system has been moving slowly east during the last 24 hours, however influence from a mid-level ridge extending from the east should begin to steer the system southwest during the next few hours, and this movement looks to be maintained until landfall on the central Queensland coast during Thursday night or Friday morning. NWP models suggest broadly that moderate northeasterly shear will persist over the system during most of this period and intensification is expected to be slow. There is a significant possibility that tropical cyclone intensity may not be reached.

Regardless of whether the system develops into a tropical cyclone, the pressure gradient between the low and a high in the Tasman Sea will produce a broad area of gales and heavy rain which will have a significant impact on the southern Queensland coast.

Tropical Cyclone Watches/Warnings
=============================
A TROPICAL CYCLONE WATCH is in effect for St Lawrence to Double Island Point

Tropical Cyclone Warning Center Darwin
Tropical Cyclone Advice #13
TROPICAL CYCLONE LAM, CATEGORY TWO (13U)
6:04 AM CST February 18 2015
========================================

At 6:00 AM CST, Tropical Cyclone Lam, Category Two (981 hPa) located at 11.3S 137.6E or 140 kilometers northeast of Nhulunbuy Airport and 230 kilometers east northeast of Elcho Island has 10 minute sustained winds of 55 knots with gust of 75 knots. The cyclone is reported as moving west northwest at 4 knots.

Storm Force Winds
=================
30 NM from the center

Gale Force Winds
===============
90 NM from the center in northeast quadrant
60 NM from the center in southeast quadrant
60 NM from the center in southwest quadrant
90 NM from the center in northwest quadrant

Dvorak Intensity: T3.5/4.0/D0.5/12 HRS

Tropical Cyclone Lam is expected to continue intensifying as it moves in a general westwards direction before turning towards the southwest into Thursday.
Hazards:

GALES with gusts to 110 km/h are currently being experienced at Cape Wessel and are expected to develop elsewhere in coastal areas between Elcho Island and Cape Shield, including Nhulunbuy during the morning. These GALES are likely to extend further west to Goulburn Island and possibly south to Groote Eylandt later in the day or into early Thursday.

VERY DESTRUCTIVE winds with gusts greater than 170 km/h may develop over the Gove Peninsula and northeast Wessel islands from midday today. VERY DESTRUCTIVE winds may also extend further west to Milingimbi overnight tonight.

GALES may extend west to Croker Island or south to Port Roper during Thursday depending on the track the cyclone takes.

Coastal residents between Elcho Island and Cape Shield, including Nhulunbuy are specifically warned of a VERY DANGEROUS STORM TIDE as the cyclone center crosses the coast. Tides will rise significantly above the normal high tide, with DAMAGING WAVES and VERY DANGEROUS FLOODING.

HEAVY RAIN is likely to cause flooding of low-lying areas in the northeast Top End during today and persist into Thursday.

Forecast and Intensity
====================
12 HRS 11.4S 137.2E - 70 knots (CAT 3)
24 HRS 11.4S 136.7E - 80 knots (CAT 3) northeast of Elcho Island
48 HRS 12.7S 136.2E - 60 knots (CAT 2) northwest of Cape Shield
72 HRS 14.9S 134.7E - 25 knots (Tropical Low) nearby Port Roper

Additional Information
===================
Tropical cyclone Lam is continuing to move in a westwards direction under the influence of a mid-level ridge situated across central Australia. The system should continue moving in this direction towards the northeast Top End before developing a south southwesterly track during Thursday due to a weakening of the mid-level ridge and interactions with an upper trough across southern Australia.

The current intensity of tropical cyclone Lam remains at a category 2, but the system is expected to intensify into Wednesday. Easterly wind shear is expected to decrease during Wednesday, in combination with warm sea surface temperatures and the potential development of two outflow channels, this may lead to a period of rapid intensification.

Dvorak analysis was based on an embedded center pattern with a colder than white surrounding grey shade, giving a DT of 5.0. MET and PAT were 3.5. FT was based on MET as DT was not completely clear. CI was maintained at 4.0. The position was determined using Gove Airport radar and is considered good to fair.

Computer model guidance appear to be fairly consistent in having a westwards track during Wednesday before developing more of a south southwesterly track during Thursday.

Tropical Cyclone Watches/Warnings
=============================
A TROPICAL CYCLONE WARNING is in effect for Goulburn Island to Alyangula, including Nhulunbuy and Groote Eylandt

A TROPICAL CYCLONE WATCH is in effect for Croker Island to Goulburn Island and Alyangula to Port Roper
Member Since: Posts: Comments:

58. flsky

If there's one thing the web can do, and do well, it's to sit in an intact structure , and comment on how the people in the rubble don't really have it that bad.
Member Since: Posts: Comments:
Quoting 62. sar2401:

This is the right link to the story. As I've said repeatedly, if you don't use the link button, your link will always fail. I don't know what to say about this poor woman but having an emergency locator beacon will do you no good if the weather is so bad that search and rescue teams can't reach you. She made a terrible decision to go on a hike alone in an area with multiple warnings out about not doing that very thing. RIP.


I think the issue might be the "link button" isn't a very intuitive thing to find.
Member Since: December 31, 1969 Posts: Comments:


Tampa Bay area. 34 shown for Tampa low on Friday morning, which means I'll get to the freezing mark at least for a little while.
Member Since: December 31, 1969 Posts: Comments:
Quoting Catherdr:
A casualty of the recent storm in the Northeast

http://www.bloomberg.com/news/articles/2015-02-17 /kate-matrosova-bnp-paribas-trader-dies-in-mountai n-hike-at-32
This is the right link to the story. As I've said repeatedly, if you don't use the link button, your link will always fail. I don't know what to say about this poor woman but having an emergency locator beacon will do you no good if the weather is so bad that search and rescue teams can't reach you. She made a terrible decision to go on a hike alone in an area with multiple warnings out about not doing that very thing. RIP.
Member Since: December 31, 1969 Posts: Comments:
NWS has a low of 29 for KDAB Fri. morning. Still don't think we are making it out of the 40s on Thurs. but we will see.

Link
Member Since: December 31, 1969 Posts: Comments:
Quoting Sfloridacat5:
NOAA's snowfall map. Not so sure about it's accuracy though.
It's certainly not accurate for Alabama, and I don't think it's accurate for Mississippi in terms of snow. Since it's for yesterday evening at 6:00 pm CST, and the scale with the white/gray color is 0.39" and less, maybe it's extrapolated ice reports instead.
Member Since: December 31, 1969 Posts: Comments:
Glad I'm not there

Wed70% Precip. / < 1 in
Mostly cloudy with snow showers developing during the afternoon. High 34F. SE winds shifting to W at 10 to 20 mph. Chance of snow 70%. Snow accumulations less than one inch. Winds could occasionally gust over 40 mph.

Wed Night20% Precip. / 0 in
Some lingering evening flurries or snow showers. Some clouds early will give way to generally clear conditions overnight. Low 3F. Winds WNW at 10 to 15 mph.

Thu10% Precip. / 0 in
Intervals of clouds and sunshine. High 14F. Winds WNW at 10 to 15 mph.

Thu Night0% Precip. / 0 in
Some clouds early will give way to generally clear conditions overnight. Low -3F. Winds NW at 5 to 10 mph.
Member Since: Posts: Comments:
or Galveston, or Mobile, or New Orleans, etc, etc. Such an ignorant comment - you, Mah, should be ashamed.
-
Quoting 29. ColoradoBob1:



Probably get an argument about that in Tacloban ..........




Quoting 5. MahFL:

No one really cares about a bad hurricane every 10 years, they just rebuild.
Member Since: Posts: Comments:
Quoting LAbonbon:
{snip}
which may point to even greater local intensities for prehistoric
events relative to Hurricane Bob in 1991 CE {snip}

I've snipped some of your reply out since it's you, me, and about three other people here who really care about this kind of thing. :-) Let's just look at that one statement. Bob was the most intense hurricane to hit New England since, say, 1900? I don't think many of our hurricane trackers would agree. So, why Bob? The core sample picture showed the deposition from Bob, Carol, and the Long Island Hurricane of 1938. Carol was at least as intense as Bob, and the 1938 storm was much ore intense in terms of storm surge and deposition. Bob looked bigger and more impressive on the core but I assume that's because the deposition was more recent. We know for sure we have a 1938 storm that was more intense, you can see it in the core, so why choose Bob as your marker for historical storms?

I'm not saying this study is somehow fatally flawed. I don't know enough about this part of science to even make that judgement. I do know enough about study construction to ask some questions about why things were done in a certain way. What I would like to see is another team of paleotempestologists (is that a word?) get the same cores and run the same tests to see if they come up with the same answers. That's the way we replicated studies in biology and I don't see why it wouldn't apply here.
Member Since: December 31, 1969 Posts: Comments:
NOAA's snowfall/depth map. Not so sure about its accuracy though.
Member Since: December 31, 1969 Posts: Comments:
Quoting 44. tampabaymatt:



Yes, I'm in the Citrus Park area.


Oh ok, yeah the line definitely got heavier after so it's surprising you got even that much, must be efficient rain makers.

Instability was very low with this front which is why it's a solid but thin line, not very tall, deep convection, just shallow forced stuff by moisture and incoming front and energy.
Member Since: December 31, 1969 Posts: Comments:



light snow on wednesday night!! 1 to 3 inches
Member Since: December 31, 1969 Posts: Comments:
Some proxy indicators for past climate temperature are pretty sound. Foraminfera shells in sea bed sediments, pollen in lake varves, for example, are hard to argue with.

Tree rings as a proxy indicator for past temperatures are a bit more 'iffy', it seems to me. Tree growth is also determined by availability of water and possibly also the abundance of insect pests. So, I tend to put less faith in the palaeodendrochronological record (I'm always looking for a chance to sneak that word in).

However, I'm completely at a loss to understand the relevance of tree ring data for major hurricane frequency. Could be there's a perfectly sound rationale I'm unaware of, but I remain to be convinced.
Member Since: Posts: Comments:
A casualty of the recent storm in the Northeast

http://www.bloomberg.com/news/articles/2015-02-17 /kate-matrosova-bnp-paribas-trader-dies-in-mountai n-hike-at-32
Member Since: Posts: Comments:




cold weather !!
Member Since: December 31, 1969 Posts: Comments:
For what it's worth: Digging for more of this paleohurricanology I came across this thesis:

Erick Braun: Enhancing Georgia's Paleohurricane Record: A Comprehensive Analysis of Vibracores from St. Catherines Island
Date of Award: 5-10-2014
Abstract: Hurricanes are amongst the most devastating of the world’s natural disasters and can cause billions of dollars’ worth of damage every year. Efforts to predict where and when tropical cyclones might strike, then, could potentially save money and lives. A lack of data exists for the GA coast, and the future direction of climate change could potentially bring more hurricanes to the state. This study provides information to enhance the paleohurricane record by examining three vibracores drawn from St. Catherines Island, GA. After interpreting the environments that generated the sediment found in one of these cores and corroborating evidence from the additional cores, six potential hurricane events were discovered, five of which were likely major hurricanes, category 3 or higher. Magnitudes were determined by comparison to event six, thought to be “The Great Gale of 1804”, a major hurricane recorded by the sedimentary record of St. Catherines Island.
Member Since: Posts: Comments:
Quoting 37. CybrTeddy:

Third inactive Atlantic hurricane season in a row coming up? While the details entering into this hurricane season remain unclear, this isn't a positive sign for an active hurricane season. If anything, this signals another 2013 style hurricane season. Warm water north of 35N, leaving the focus of heat well out of the MDR (Main Development Region). There is still plenty of time for this to change however.






And what change can make the AMO go positive?

vs
Member Since: Posts: Comments:


more cold weather coming and more snow and rain for the northeast
Member Since: December 31, 1969 Posts: Comments:
Quoting 19. Neapolitan:

Well, scientists have a pretty good idea--and it'll be a whole lot more than "half an inch":




I suppose the silver lining to the land subsidence in the big cities of the Mid Atlantic is that people may wake up to reality sooner. Too little too late though.
Member Since: Posts: Comments:
Light Rain

46°F

8°C

Humidity79%
Wind SpeedNW 7 mph
Barometer29.94 in (1013.8 mb)
Dewpoint40°F (4°C)
Visibility9.00 mi
Wind Chill42°F (6°C)

Last Update on 17 Feb 2:53 pm EST

Current conditions at

Tallahassee, Tallahassee Regional Airport (KTLH)

Lat: 30.39°N Lon: 84.35°W Elev: 79ft.

More Local Wx | 3 Day History | Mobile Weather




We've had 0.53 so far here, which is better than I expected out of this. Most of the rain is light now, about 0.40 of it fell early in the morning in the warmer air ahead of the cold front. Since then it's been cold, raw, and windy light rain.

Winter is making itself known here now, its been a nasty day to walk around campus between classes.

Member Since: December 31, 1969 Posts: Comments:
Strange, I thought I lived in southeastern North Carolina.

Member Since: Posts: Comments:
Quoting 42. Jedkins01:



You're in northwest Hillsborough right? If so that's not bad considering the line was thinner and looked weaker just a few frames ago when it went through your area. It looks like it's gotten quite a bit stronger and more solid as it's progressed further southeast.

That's likely due to the next shortwave digging in which has brought rain back into our area up here as well.


Yes, I'm in the Citrus Park area.
Member Since: December 31, 1969 Posts: Comments:


Tampa airport is getting drilled right now.
Member Since: December 31, 1969 Posts: Comments:
Quoting 35. tampabaymatt:

Just picked up 0.24" from that squall line. More on the way tonight.


You're in northwest Hillsborough right? If so that's not bad considering the line was thinner and looked weaker just a few frames ago when it went through your area. It looks like it's gotten quite a bit stronger and more solid as it's progressed further southeast.

That's likely due to the next shortwave digging in which has brought rain back into our area up here as well.
Member Since: December 31, 1969 Posts: Comments:
Quoting 32. sar2401:

Did you look up any of the studies cited? If so, are you convinced that the other studies were looking at the same things in this study, with the same level of temporal resolution, over the same time periods? I'm not. The studies I was able to access seem to show they were mainly concerned with trying to figure out SST, and most went back for about 1,000 years or so. It looked to me like the authors were using the studies cited to support claims of higher SST's during the same period they claim they were able to detect these increases in cat 2 plus hurricanes in the prehistoric past. That's fine, but the other studies don't seem to directly relate to hurricane return ratios.

No, I didn't, but I did find the abstract for Mallinson (the Outer Banks research). You can read the study for $35.95 (!), but here's the abstract:

Abstract
The Outer Banks barrier islands of North Carolina, USA, contain a geologic record of inlet activity that extends from ca. 2200 cal yr BP to the present, and can be used as a proxy for storm activity. Optically stimulated luminescence (OSL) dating (26 samples) of inlet-fill and flood tide delta deposits, recognized in cores and geophysical data, provides the basis for understanding the chronology of storm impacts and comparison to other paleoclimate proxy data. OSL ages of historical inlet fill compare favorably to historical documentation of inlet activity, providing confidence in the technique. Comparison suggests that the Medieval Warm Period (MWP) and Little Ice Age (LIA) were both characterized by elevated storm conditions as indicated by much greater inlet activity relative to today. Given present understanding of atmospheric circulation patterns and sea-surface temperatures during the MWP and LIA, we suggest that increased inlet activity during the MWP responded to intensified hurricane impacts, while elevated inlet activity during the LIA was in response to increased nor'easter activity. A general decrease in storminess at mid-latitudes in the North Atlantic over the last 300 yr has allowed the system to evolve into a more continuous barrier with few inlets.
Member Since: December 31, 1969 Posts: Comments:
Quoting 28. sar2401:

I read it also. It falls over from the first indicator storm. From the study "...the historical interval are consistent with severe hurricanes in 1991 (Bob)...". I don't know how they defined "severe" but Bob was not a cat 3 at landfall in Rhode Island and certainly was not a cat 3 when it moved over Salt Pond. How do you start with Bob and use that to extrapolate to the other storms as being cat 3's? In addition, the core samples came from one pond in Massachusetts. Again, from the study: "A shift in activity to the North American east coast occurred ca. 1400 CE, with more frequent severe hurricane strikes recorded from The Bahamas to New England between 1400 and 1675 CE." Now it includes the Bahamas? The whole East Coast? What? Based on what evidence?

Their own calculations for return rate ratio was based on the number of cat 2 plus hurricanes hitting New England based on the best track database over the past 162 years, not cat 3 plus. (Section 6.2, first paragraph). The occurrence of cat 3 plus events was, and is, so rare that there wouldn't have been enough of them to use for a reasonable base of calculation. Why then does Donnelly make the statement in the press release quoted above that the return rate of cat 3 plus hurricanes is going to increase when the study doesn't use that criteria?

I have lots of other questions about methodology and conclusions that don't make sense to me either. I saw nothing in the way they were able to resolve temporal distribution that would have excluded sedimentation deposition from a powerful Nor'easter rather than a tropical cyclone. I won't plow thorough them all here and have the blog want to kill me. At the very least, Donnelly, the lead researcher, is making statements for attribution that are clearly not supported by the study.

sar, they are building on the work of others. The references to the Bahamas and the Carolinas came from other studies and published papers. (I have not looked up these papers.)

Did you happen to read the supporting documentation for the paper on AGU's site, "Attribution for Historical Event Beds"? It goes in depth as to how other, 'lesser' storms were excluded. Both the paper and the supporting documentation go into detail as to why Bob and the two storms from the 1600s were included as the marker beds. The discussion of particle size, stratigraphy, and common dating techniques for stratigraphy were discussed and shown graphically.

Regarding the suggestion that the storms were stronger, this from the paper discuses why they think that may be the case:

"Given modest increases in sea level over the last 2000 years in the region [Donnelly, 1998]
(~2 m), the barrier fronting Salt Pond has likely transgressed landward with time, with recent
historical shoreline retreat rates of ~10 m per century [Thieler, 2013]. As a result of this
landward barrier translation, older event beds recorded in SP2 were likely transported greater
distances than recent ones, which may point to even greater local intensities for prehistoric
events relative to Hurricane Bob in 1991 CE
.

Twelve of the thirty-two prehistoric event beds contain more coarse sediment than that
deposited by the Great Colonial Hurricane in 1635 CE (event bed #3), despite likely being
transported a greater distance due to barrier transgression related to sea-level rise. The largest
coarse anomaly peak occurs at 693 cm (event bed #26, Fig. 2) and dates to ~540 CE. A rip-up
clast of fine-grained organic sediment incorporated in the ~540 CE quartz sand deposit
further attests to the layers origin from a high-energy event (Fig. 2d). While the amount of
coarse fraction transported is only one metric for ascertaining the local intensity of an event
[Brandon et al., 2013; Woodruff et al., 2008a], these large coarse fraction peaks suggest that
the competence of local event driven waves and currents to transport sand sized particles was
greater during recent prehistory than experienced over the last ~400 years. This implies that
many of the prehistoric hurricanes may have locally been more intense than those impacting
the region historically
."

And the blog shouldn't be upset, because honestly, the blog topic is the very paper we are discussing.
Member Since: December 31, 1969 Posts: Comments:


NE St. Petersburg
Member Since: December 31, 1969 Posts: Comments:
Quoting MAstu:
Kam-biu Liu has done a lot of research in this area. Here is a presentation on the subject:

Link
I've seen that presentation before and it's pretty interesting. The LSU project was looking at the return rate for cat 4 plus storms on the Caribbean and Gulf Cost going back about 3,800 years. Their data seems to show we can expect one of these catastrophic storms every 300 years or so. Given just what we've seen since 1995, it seems apparent that the 300 years is a statistical measure and not an actual predictor in any year, decade, or century.
Member Since: December 31, 1969 Posts: Comments:
Third inactive Atlantic hurricane season in a row coming up? While the details entering into this hurricane season remain unclear, this isn't a positive sign for an active hurricane season. If anything, this signals another 2013 style hurricane season. Warm water north of 35N, leaving the focus of heat well out of the MDR (Main Development Region). There is still plenty of time for this to change however.





Member Since: Posts: Comments:
as for hits 1 in 10 yrs it does not happen that way. speaking of that miami really has not had anything too bad since andrew.
Member Since: December 31, 1969 Posts: Comments:

Viewing: 86 - 36

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10Blog Index

Top of Page

Category 6™

About

Cat 6 lead authors: WU cofounder Dr. Jeff Masters (right), who flew w/NOAA Hurricane Hunters 1986-1990, & WU meteorologist Bob Henson, @bhensonweather