CybrTeddy's tropical weather blog

TS Katia likely to become a powerful hurricane, GOMEX development possible 8/30/11

By: CybrTeddy, 8:12 PM GMT on August 30, 2011

Good afternoon and welcome to my tropical weather update for Tuesday, August 30th, 2011. Tropical Storm Katia has arrived on scene and is already a 60 mph system. It has a high likelihood to become a very powerful hurricane over the next few days. And we also have a quickly growing possibility that a Humberto-like situation could be emerging in the Gulf of Mexico.

Tropical Storm Katia - likely Hurricane Katia tomorrow.
Our 11th named storm of the season has arrived on scene, Katia. Katia's formation marks the 2nd earliest use of the K name if I can remember correctly in history. The earliest obviously, being Katrina in 2005. Katia is currently located at 125N, 346W. Maximum sustained winds according to the ATCF have increased rapidly to 60 mph with higher gusts, and it appears likely that Katia will become a very powerful Category 4 hurricane over the weekend.

(fig 1. Tropical Storm Katia as of this update.)

Obviously, over the next few days Katia will be one of the top stories as expected. Katia will probably become a hurricane tomorrow night or Wednesday morning, and I foresee Katia becoming a major hurricane on Thursday, perhaps peaking as a Category 4 either on Friday or Saturday morning, and should retain its status as a very powerful hurricane over the weekend. Katia does pose some threat to land, but I do not think anymore it likely that Katia will hit the United States. There are several shortwave troughs coming through and one will just be enough to create a weakness for Katia to follow.

(fig 2. TS Katia's forecast track)

Caribbean disturbance a threat to become Lee in the Gulf.
Our next area of interest is associated with actually two areas. One is a cut off MLC from a trough situated in the Gulf of Mexico. Another is the tropical wave that is currently over the western Caribbean, generating some moderate showers and thunderstorms. The ECMWF, GFS and CMC all continue to show this will become at least a 60-70 mph Tropical Storm in the Gulf of Mexico off the coast of Texas once that tropical wave begins to interact with the MLC. The reason the intensity being depicted on the models are so high is because it will probably not go straight inland, rather the Texas high will force this system south, along the coast of Texas then strengthening into a potent system.

We'll watch this all very closely.

CybrTed

Damaging Irene hits the NE, Jose a oddity, 92L - the one to watch. 8/28/11

By: CybrTeddy, 3:19 PM GMT on August 28, 2011

Good morning and welcome to my tropical weather update for Sunday, August 28th, 2011. Irene finally made its final landfall in the Northeast today as a Tropical Storm, but that's not to say it was without damage. A lot of people are being complacent about the effects of this storm. Let me remind all of you now that Irene has caused AT LEAST 1 billion dollars in damages to the islands in the Caribbean and Puerto Rico, probably more in the range of 3 billion dollars in damages. Just based on that alone, Irene will almost certainty be retired in 2012 and replaced with another name. I suggest Ivory, or Ianna. Anyways, back to the point, early reports from the NE indicate that although New York City was relatively spared, there has been pretty hefty flooding in New Jersey, which Irene made a direct landfall in, and wind damage in Connecticut and Rhode Island. Please people, do not make assumptions that even though NYC was predicted to receive heavy damage does NOT mean that Irene didn't cause damage.

(fig 1. Irene as of this update.)

Irene should go extra-tropical tonight, and that will end my updates on Irene.

Tropical Storm Jose. No way.
Forecasting tropical cyclones has always been subjective, but this just takes the cake on that issue of subjectivity when it comes to named storms. Jose was classified as a naked swirl with no convection for over a hundred miles away. Irene's outflow has been hammering the convection away, and looks like a remnant low. This will probably be my only update on Jose, which shouldn't have been named in my opinion anyways.

(fig 2. Tropical Storm Jose.)

(fig 3. Forecast track for Tropical Storm Jose.)

92L likely to become a powerful Hurricane.
As Irene moves out, and Jose does its little naked dance, the main focus will shift to 92L off Africa, which has the potential to become quite the system. 92L has as much, if not more, model support than Irene did even and appears to be organizing minute by minute. Satellite reveals a organizing tropical wave with good spiral banding and moderate shear impacting the right side, this is causing outflow to be slightly restricted. The GFS, CMC, ECMWF, NOGAPS, and even the overly-conservative UKMET indicates that 92L will become Katia, and a powerful hurricane at that. It is too early to tell whether or not 92L will have impact on land, but its certainly possible. I really don't see much in the way of troughing on the models, high pressure seems to be really dominating the steering flow right now. The GFS seems to develop a low-pressure center (Lee? Who knows) that creates a weakness for 92L to follow in a few days.

(fig 4. Satellite image of 92L.)

(fig 5. Computer models on 92L.)

2011 nearly ties 2005 in named storms so far.
One final thing I wanted to talk about is just how active this season has been. Sure, we've had a lot of weak systems but think about it - the first hurricane of the season goes down in history as the first direct NE hurricane landfall in years. It was the first hurricane to hit New Jersey since 1903 (? - correct me in the comments if it was 1904). We are one named short of 2005 right now, which had Category 5 Katrina in the Gulf of Mexico today. Thankfully, this is not the case with anything out there today but still, this season is very active. We have seen 6 named storms this month and we will probably see Katia by the end of the month, say the 31st. By that logic, we will probably see 7 named storms in September, ending the month off with Sean. October will probably also be very active, with I would think possible 3 named storms. That would put us to 21 named storms, or the 2nd most active hurricane season ever recorded. I think that in November we could see our final storm, Alpha, and make this year the 2nd year ever to go into the Greek alphabet and the first time ever that the same naming list has been exhausted twice.

We'll watch this situation closely. Take care if your in Irene's path, it can still cause damage.

CybrTed

Major Hurricane Irene a very serious threat to the US East Coast 8/24/11

By: CybrTeddy, 7:51 PM GMT on August 24, 2011

Good afternoon everyone and welcome to my very short tropical weather update for Wednesday, August 24th, 2011. Well.. Irene has exploded, and we have 90L that looks like it will become Jose. Anyways, Irene is now a Category 3 hurricane with maximum sustained winds of 120 mph. Preps need to be made STAT along the East Coast, in the short term North Carolina and Virginia and eventually New York City and the NE US.

(fig 1. Hurricane Irene as of this update)

I am sorry for the small update, as I am not using my PC.

CybrTed

Hurricane Irene - a major threat to the United States 8/22/11

By: CybrTeddy, 6:44 PM GMT on August 22, 2011

Good afternoon and welcome to my tropical weather update for Monday, August 22nd, 2011. I apologize for my lack of updates yesterday, as I was without internet for the longest time. I had to rely on The Weather Channel for updates, so I am relatively aware of what has transpired in the last 24 hours. Irene has strengthened into a Category 1 hurricane with 80 mph winds. It appears to me that dry air and moderate land interaction with Puerto Rico has caused a noticeable gap north of the CDO of Irene. But if you don't look at that and focus on the CDO, you'll see a maintaining hurricane.

(fig 1. Hurricane Irene as of this update)

Where is Irene going to go?
A lot of the track will be dependent on the short term intensity. If Irene suddenly weakens, it will be forced into Haiti with further weakening likely. It will then be forced more westward, putting FL well into play. If Irene suddenly decides in the next 36 hours to bomb out into a major, it will be forced more north and it might just scrape the US coastline. Conditions are very favorable for further intensification of Hurricane Irene at this time in the Bahamas, and no one should put their guard down. I do not think it is likely that Irene will be forced out to sea though, not unless like I said if Irene decides to become a major in the next 36 hours. Judging by the current rate of organization, I do not think this is likely.

(fig 2. Dynamical models as of the latest run)

Basically, anyone from Miami to Virginia should not take their eyes off Irene, though I think those in South Carolina coast needs to be aware that right now even though the track has it pointed to you does NOT mean it will hit you.

Intensity forecast for Irene.
Like I said, a lot of the intensity will have to do with the track. The problem is though that we all have to be aware, once Irene gets into the Bahamas there is very warm, perhaps the warmest in the Atlantic Basin, and with favorable wind shear and a moist upper level environment.. this could really take off. The NHC discussion notes this possibility and has it become a 115 mph Hurricane. I think its entirely possible it could be stronger, 120-125 mph Category 3 hurricane. Another thing is Irene's size, its size makes it less prone to periods of weakening except eyewall replacement cycles.

(fig 3. Radar out of Puerto Rico of Irene)

Keep on guard everyone, from Miami to Virginia do not keep your eyes off this.

CybrTed

SPECIAL UPDATE Tropical Storm Irene 8/20/11

By: CybrTeddy, 11:35 PM GMT on August 20, 2011

Good afternoon and welcome to my special tropical update for Saturday, August 20th, 2011. Well, we now have our 9th named storm.. we're only behind 2005 in activity so far and tied with two other seasons IIRC. Tropical Storm Irene is located at 14.9°N 58.5°W, maximum sustained winds have increased to 50 mph with higher gusts, and Irene could become a hurricane on Monday. Satellite shows that the anti-cyclone is doing its job, fanning convection around the weak LLC that the recon found. There has been a new blowup of convection over Irene that indicates that Irene is going to begin to tighten up its LLC and strengthen. The biggest wrench in the intensity forecast is how it will do when or if it interacts with Hispaniola. We saw with Emily that systems get torn apart before our very eyes once they begin to effect the island. It also depends on the size, if 9Irene is much larger than Emily, which is possible, than it will be less prone to rapid weakening.. and if its stronger than Emily, it will also probably not weaken to a TD or dissipate. Another thing is that Irene will be coming in at a different angle than Emily, hitting the Dominican Republic and heading westward, this setup would be less likely to dissipate a storm, as we saw with Fay and Georges.

(fig 1. Tropical Storm Irene.)

(fig 2. Irene's forecast track.)

The NHC discussion indicates that although after Cuba Irene will only strengthen to a 65 mph Tropical storm, it is entirely possible it could be stronger and possibly a hurricane by the time it approaches the USA. Irene though at the time is a serious threat to Hispaniola, which could be facing a hurricane as this approaches them the next 48 hours. Hispaniola, particularly Haiti, is very prone to flash floods and other devastating effects associated with a tropical cyclone. Irene right now is in a favorable upper level environment, and like I said further strengthening is expected. Full details tomorrow AM.

CybrTed

Harvey Strengthening, 97L remains a threat to the US 8/20/11

By: CybrTeddy, 3:27 PM GMT on August 20, 2011

Good morning and welcome to my tropical weather update for Saturday, August 20th, 2011. The tropics are active this morning, with three systems to watch, two of which appear poised to have direct consequences on land. The first being Tropical Storm Harvey, the 8th, believe it or not, named storm of the 2011 Atlantic Hurricane Season. It is worth nothing that Danielle didn't form until tomorrow last year, and that Hermine didn't form until the 5th of September.. and we appear to be getting ready to have our 'I' storm, Irene, by the end of the weekend or on Monday.

Harvey could become a hurricane just before landfall.
Yesterday, Harvey put on an impressive round of intensification that wasn't expected and went up to a 60 mph storm. Harvey still has a chance to become a hurricane, but that window of opportunity has rapidly diminished now that the recon did not find at least a 70 mph Tropical Storm. This tells me that Harvey will probably peak at 65 mph just before landfall unless something drastic happens, which can happen in those warm and shallow sea surface temperatures. Regardless, Harvey is mainly a rainfall threat anyways to these areas and Belize could experience flash floods and heavy downpoors the upcoming days. Harvey is no threat to enter into the Gulf of Mexico.

(fig 1. Tropical Storm Harvey as of this update.)

Invest 97L - the biggest threat.
Invest 97L has become much better organized in the last 24 hours, with deep convection developing around an area of low pressure associated with this wave. It is questionable though that it has a closed surface circulation, and a recon is scheduled to go into 97L to check whether or not this has occurred. If so, 97L will be declared Tropical Depression 9 and TS warnings will go up for Puerto Rico, maybe even hurricane watches depending on how strong the NHC thinks it will get.

(fig 2. Invest 97L as of this update.)

Invest 97L has heavy model support for continued development, the ECMWF has locked onto develop and they indicate that it will become a hurricane. The GFS also continues to show a hurricane in the Gulf, a west coast Florida landfall to be exact, the CMC continues to go south compared to the ECMWF and GFS. The often conservative UKMET has this also becoming a tropical cyclone and takes it on a similar path to the CMC. NOGAPS is with the ECMWF and GFS on this system heading towards Florida.

The biggest wrench in the intensity forecast is how it will do when or if it interacts with Hispaniola. We saw with Emily that systems get torn apart before our very eyes once they begin to effect the island. It also depends on the size, if 97L is much larger than Emily, which is possible, than it will be less prone to rapid weakening.. and if its stronger than Emily, it will also probably not weaken to a TD or dissipate. Another thing is that 97L will be coming in at a different angle than Emily, hitting the Dominican Republic and heading westward, this setup would be less likely to dissipate a storm, as we saw with Fay and Georges.

The forecast track is even more uncertain, though I do not think 97L will go out to sea or heads towards Texas. I think that Mississippi on wards has to watch 97L and especially Florida needs to watch this systems progress very closely. I will not narrow down a state though exactly where 97L will hit, or how strong it will be. If we believe the models though, it is possible it could be a hurricane.

(fig 3. Computer models on 97L.)

Invest 98L not a real threat to develop.
Invest 98L is producing limited showers and thunderstorms, and is not a real threat to develop. It is heading into an area of higher SAL and wind shear and that should inhibit further development. In anyways, 98L is not a threat to land.

I will have an update later today if there are any changes in 97L or Harvey.

CybrTed

An active Atlantic - TD8, 97L, 98L. 8/19/11

By: CybrTeddy, 3:38 PM GMT on August 19, 2011

Good afternoon and welcome to my tropical weather update for Friday, August 19th, 2011 and boy what a day it is. We have three systems out in the Atlantic, two of which are going to threaten land, and two that have a chance to become powerful hurricanes over the next few days. Here's the latest advisory/TWO package.
TD#8
...HURRICANE HUNTER AIRCRAFT FINDS DEPRESSION JUST BELOW TROPICAL-STORM STRENGTH...TROPICAL STORM WARNING ISSUED...
11:00 AM EDT Fri Aug 19
Location: 16.1°N 83.7°W
Max sustained: 35 mph
Moving: W at 10 mph
Min pressure: 1005 mb


8AM TWO
A LARGE TROPICAL WAVE LOCATED ABOUT 900 MILES EAST OF THE LESSER
ANTILLES IS SHOWING SIGNS OF ORGANIZATION. ENVIRONMENTAL CONDITIONS
ARE EXPECTED TO GRADUALLY BECOME MORE CONDUCIVE FOR DEVELOPMENT AS
THE DISTURBANCE APPROACHES THE LESSER ANTILLES ON SATURDAY. THIS
SYSTEM HAS A MEDIUM CHANCE...40 PERCENT...OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES WESTWARD AT 20 MPH.

A BROAD LOW PRESSURE SYSTEM IS GRADUALLY BECOMING BETTER DEFINED
ABOUT MIDWAY BETWEEN THE CAPE VERDE ISLANDS AND THE WEST COAST OF
AFRICA. THE LOW IS PRODUCING A LARGE AREA OF THUNDERSTORMS...AND
UPPER-LEVEL WINDS ARE FORECAST TO BE CONDUCIVE FOR DEVELOPMENT AS
IT MOVES WEST TO WEST-NORTHWESTWARD AT 10 TO 15 MPH. THIS SYSTEM
HAS A MEDIUM CHANCE...50 PERCENT...OF BECOMING A TROPICAL CYCLONE
DURING THE NEXT 48 HOURS. REGARDLESS OF DEVELOPMENT...LOCALLY
HEAVY RAIN AND STRONG GUSTY WINDS ARE POSSIBLE IN THE CAPE VERDE
ISLANDS TODAY THROUGH SATURDAY.


Tropical Depression #8 poised to become Tropical Storm Harvey.
Our first area of concern is the one that is about to threaten land, 93L finally got its act together to become a Tropical Depression, and should be a Tropical Storm soon, later today actually. Recon found that TD8 had strengthened overnight and is very near Tropical Depression status. I expect that later today we'll be on our 8th named storm.

(fig 1. Latest GOES-E CONUS image of TD8)

TD8 managed to avoid making landfall in Central America for now, as it looked for a while that it wouldn't be able to avoid the coastline and hit without any further development. This no longer appears to be the case, as the recon found that TD8 managed to relocate its COC further north and giving it a much better chance of strengthening. We saw last year Karl and Alex both become 60mph Tropical Storms as it neared the Yucatan. This should become at least a 50 mph Tropical Storm as it hits Belize and the latest NHC advisory package indicates such probabilities of this happening.

(fig 2. TD8's current advisory package track)

***UPDATE: TD8 has, as expected, become Tropical Storm Harvey. Satellite estimates are pretty high atm, so there's a possibility Harvey is stronger than 40 mph.

97L - our biggest threat so far in the season.
The computer models have been, and have been continuing to show very persistent indications that this certain tropical wave will become a very dangerous hurricane somewhere either in the eastern Bahamas or the western Caribbean near Jamaica. This wave is now called 97L, and the NHC is giving it a 40% of becoming TD9 or 10 in the next 48 hours. I think this is reasonable, as some of the computer models show 97L becoming a TD on Sunday. As of right now, the GFS, ECMWF, CMC and NOGAPS all predict that 97L will become at least a Category 1 hurricane, and probably stronger in the Caribbean or in the Bahamas.

(fig 3. Invest 97L on the GOES-E satellite image)

The models have been flipfloping, but they all are in agreement that 97L will enter the Eastern Caribbean and strengthen into a strong-TS as it nears Puerto Rico. The GFS says that it will miss both Puerto Rico and Hispaniola and continue to strengthen as it nears Cuba, this is certainly possible. The ECMWF says that 97L will go right over Hispaniola and head towards Florida as a hurricane, the CMC is pretty much inline with the GF. I think that ECMWF might be the northern outlier, but that certainly does not mean that Florida should be less on alert, in fact it appears the threat to western Florida to Louisiana has increase over the last 12 hours.

(fig 4. Computer model ECMWF showing a Florida landfall in 192 hours.)

That being all said in the models, I expect that 97L might become a Tropical Depression as soon as Sunday evening, and that we'll see steady strengthening in a favorable upper level environment over the next few days. I expect that this system will either threaten or make landfall in Hispaniola anywhere from a 60 mph TS to a Category 1 hurricane. After that it is hard to tell, but I doubt that 97L will head out to sea. All interest in the Antilles to Florida must pay very close attention to this system.

Invest 98L racing with 97L to become TD9.
Another Tropical wave is just off Africa and is showing signs of increased organization. The NHC has this area at a 50% of becoming a TD in 48 hours and it is certainly possible that this could become Irene before 97L. This also has good model support from the GFS/ECMWF to become another named storm, perhaps even a hurricane later in the forecast period. It is difficult to say how strong it will get but I highly doubt that 98L will become any serious threat to the USA, maybe Bermuda in the very long run.

(fig 5. satellite image of Invest 98L)

We'll be watching this situation very closely.

CybrTed

Gert weakens, 93L, new African wave our biggest threat. 8/16/11

By: CybrTeddy, 2:07 PM GMT on August 16, 2011

Good morning and welcome to my tropical weather update for Tuesday, August 16th, 2011. The tropics are very active once again this morning, with three systems talking, two of which have a legit threat to develop into tropical cyclones and one of which is already a cyclone, Gert. Before I begin, I must again note how active this hurricane season has been. This is so far the 4th earliest we've seen the 'G' name in Atlantic history, and now everything looks like we'll be seeing a massive jolt in activity.

Tropical Storm Gert not going to become a Hurricane.
Our first system is Gert. Tropical Storm Gert is located at 36.4°N 59.6°W, maximum sustained winds have decreased to 45 mph. Further weakening is expected as Gert heads into lower sea surface temperatures and a higher shear environment. Tropical Storm warnings have been cancelled for Bermuda, and no other areas of land are threatened from Gert. On satellite Gert has a sheared and disorganized look, and could dissipate later tonight or tomorrow morning. This will probably be my final update on Gert.

(fig 1. Tropical Storm Gert as of this update.)

Invest 93L still out in the Atlantic.
We are stil talking about invest 93L, currently located in the Eastern Caribbean. 93L is disorganized and producing an area of scattered showers and thunderstorm. Last night due to the lack of convergence all of the heavy thunderstorm dissipated and has since come back to form a more consolidate look to it. Surface Convergence is very high - for the first time in 93L's life - this morning with a small area of consolidated convection. This could be the first sign of a developing low-level circulation. Surface pressures though in the general area are not falling at this time.

(fig 2. Invest 93L from GOES satellite)

Model support has been scattered and limited, right now the very reliable ECMWF and NOGAPS are the only two models that develop 93L into a tropical cyclone. This is a set up from at least no model support from what we where seeing yesterday. The ECMWF spins this up to a 1008 mb low with a few closed tightly clustered isobars by the end of the week. 93L is in the graveyard for cyclones in the Caribbean, due to trade winds that are commonly present over the central Caribbean that tend to suck energy away from the center. Trade winds are about 15 knots and falling slowly, which tells us to watch for any development in the western Caribbean. Based on this, I give 93L a 30% chance of ever developing into a tropical cyclone. Its main two factors are dry air and lack of a surface circulation, and might run out of time before running into central America or the Yucatan.

(fig 3. Model guidance for invest 93L.)

It is difficult to say how strong 93L will get, but I do not expect that 93L will become a hurricane due to the lack of present organization. I think 93L if it develops will develop into a moderate tropical storm before running into central America. Given that 93L is the closet threat to land, we will watch this area very closely.

(fig 4. Model intensity forecast, not to be taken seriously.)

New African wave - the one to watch.
Our final area of interest is perhaps the likeliest to become a major system. An area of disturbed weather in the ITCZ is predicted by all of the major global models to become a tropical storm or even hurricane by next week. The 00z ECMWF for the 4th run in a row developed a hurricane from this system, the 06z GFS showed a hurricane getting into the Gulf of Mexico due to a lack of a trough. The 00z CMC showed a developing tropical storm heading into the Caribbean as well, but I wouldn't take any models right now seriously in terms of a possible threat to land. I suspect though that this area might follow a path a little more north than 93L and Emily 'if' it is stronger than they where by the time they reach 50W or so. We're getting into that time of season where the big ones crank out, it happens every season and this season will be no different. We're about to see the wave train really kick up, and we might see even 3 more storms this month and even more next month. This isn't going to be one of those seasons that have little storms that do nothing, while that may be mostly what we've gotten that is going to change very soon.

(fig 5. African wave to watch.)

CybrTed

Tropical Storm Gert & 93L 8/15/11

By: CybrTeddy, 2:30 PM GMT on August 15, 2011

Good morning and welcome to my tropical weather update for Monday, August 15th, 2011. Tropics are fairly active today with two systems out in the Atlantic. The first is Tropical Storm Gert, which could be on its way to finally becoming Hurricane Gert. Then we have invest 93L located just to the west of the islands, which appears to be not at this time a imminent threat to develop.

(fig 1. invest 93L and Tropical Storm Gert.)

Tropical Storm Gert - the 7th named storm of the 2011 Atlantic hurricane season.
We are now on Gert, #7 of this season. While no 2005, this is the most active so far into the season since 2005. Later today, in 2008 Fay formed so as of this blog post 2011 is two named storms ahead of 2008, and that activity shows no signs of slowing down. Tropical Storm Gert is located at 31.5°N 63.3°W, maximum sustained winds have increased rather quickly to a 60 mph system. This can be contributed to Gert being such a small and compact system. Radar out of Bermuda shows that Gert is developing an eye, and could become a hurricane later today or tomorrow.

(fig 2. Satellite image of Tropical Storm Gert.)
Gert might continue to strengthen as I mentioned to a Category 1 hurricane. That would be our first hurricane of the season, and only 5 days late. However, it is very possible that Gert might not reach hurricane status because of now northerly shear that is starting to impact Gert, giving it a more flat look to it, limiting its outflow for intensification. That being said, I see Gert peaking at 70-75 mph before going extra-tropical. Its funny how Gert formed, split off energy from Emily. It appears to be ex-Emily's MLC that became Gert, I never would have expected then 94L to develop into a tropical cyclone. Just goes to show how unpredictable the tropics are.

Invest 93L not a threat to develop.
Our next area of interest is once-again revived invest 93L. 93L is located just to the east of the islands and will head into the Caribbean and could even track the entire length of the islands. That being said, development is unlikely in my opinion. You have a bunch of dry air in the Eastern Caribbean and no model support. There is no 850mb vort. which assures that 93L will not develop in the eastern Caribbean. It is also a fast mover, which limits time it will spend in the Caribbean. Based on all that, while I will continue to monitor 93L I do not think it will become Harvey.

(fig 3. Invest 93L satellite image)

(fig 4. Invest 93L tracking computer models)

CybrTed

Very active Atlantic: 4 invests 8/12/11 SPECIAL UPDATE AT 4:30

By: CybrTeddy, 4:17 PM GMT on August 12, 2011

Good afternoon and welcome to my tropical weather update for Friday, August 12th, 2011. The tropics are the most active they have been all year today, with 4 invests out in the Atlantic - Invest 92L & 93L (both of which are off Africa), and newly declared Invest 94L and 95L. All four of these invests have a chance at becoming a tropical cyclone over the next 72 hours, though I feel the most imminent might be the newest one, 95L.

(fig 1. Tropical Atlantic as of this update, view of all Invets)

Invest 93L serves as the biggest threat to become a dangerous system.
Our first and primary area of interest is 93L, which has lost a lot of its mojo so to speak overnight. I am surprised this didn't happen earlier, given the lack of convergence and the fact its still within the ITCZ. The sudden drop in convection signals a few things, one that it is detaching from the ITCZ and has to work on becoming able to sustain its own convection. Another is that is starting to spin up a closed low-level circulation. And the final one is the inhibiting factors, as I outlined fig.1 there is heavy SAL to the north of 93L, that appears to be getting entrained into the circulation and there is some light wind shear on the system too, inhibiting any rapid development. Based on this, I expect gradual development only the next few days. Model support for 93L has always been here and there, and that has not changed today. Though, the ECMWF does develop 93L it doesn't develop 93L until it nears the Yucatan, a scenario I find unrealistic if its to develop at all because of the favorable conditions ahead. The GFS develops this in a similar location, but its worth nothing that the GFS has been really on and off on the timing 93L becomes a tropical cyclone. The CMC and NOGAPS do not develop 93L into a tropical cyclone.

(fig 2. Satellite image of disorganized 93L.)


(fig 3. Computer models for Invest 93L)

Based on the current look of 93L and the model support it has, I do not expect 93L to become a Tropical Cyclone within the next 24-48 hours, but I do believe it might eventually once it nears the Caribbean. The more weak they stay the more west they go, and this appears to be the case here. The models that do develop 93L make sure that it goes into the Caribbean, which is concerning to me as that is a dangerous place to be for a cyclone for this time of year. Trying to find analog storms one does stick out, at least in its early embryo stages - Hurricane Dean. That is not to say this will be anything like Dean, but the fact that there is a westward moving Caribbean bound tropical wave in the same exact spot nearly that pre-Dean was on this very same date 4 years ago is very interesting. I do not expect 93L will be like this, but its interesting to see. It is rare to get a westward bound Cape Verde major hurricane. Allen and Dean are the only ones that I can think of that developed near the Cape Verde islands and made it all the way to the Bay of Campeche. For intensity, it is very possible that 93L once it starts to get its act better organized and a better consolidated look that it could eventually become our first hurricane of the season, I will go no further than to guess on a possible future intensity as much as I would a future landfall - if any.

(fig 4. Intensity models for 93L)

Invest 92L remains disorganized aswell.
Our other potiental long tracking system is invest 92L just to the west of invest 93L. Invest 92L is very disorganized at the moment, embedded within a area of low moisture and SAL, this is prohibiting any thunderstorm activity. 92L has no convergence to speak of, so I do not expect any sudden blowup of thunderstorms the next few days.

(fig 5. Satellite image of 92L.)

92L has some model support, the strongest being from the CMC which makes 92L a hurricane. The ECMWF and GFS have also developed 92L into a tropical cyclone over the coming days, but I do not feel that 92L will become a tropical cyclone over the next 48 hours. If anything, like 93L, 92L's earliest window of opporuntiy to go ahead and develop might be on Sunday PM or so, as it finally moves out of that area of dry air and can get going. 92L is moving into an area of higher SSTs and will also be more prone to strengthen and or weaken. Based on all of this, I expect for today 92L will loose most - if not all of its heavy thunderstorm activity to a point of a few bands if that. That might prompt the NHC to bump down the odds to 30%, but I expect tonight there might be another blowup and we'll see gradual organization with the pulsating convection. Afterwords, there is a trough to the north of 92L that should steer it out to sea with only a threat to Bermuda and an outside threat to the northern Islands, but I do not think that threat is very likely at all.

(fig 6. Computer models for 92L.)


(fig 7. Intensity models for 92L.)

Invest 94L.. Emily again.
Emily moved out to sea with no regeneration thank God, but while it moved out to sea a piece of energy associated with Emily split off and is now invest 94L moving over a favorable SST environment. 94L has the lowest chance of development however according to the NHC. That is probably because of the meager thunderstorm activity and dry air that is surrounding 94L. 94L is not a threat to land, and should move in a WSW fashion then a gradual turn out to sea.

(fig 8. Satellite image of 94L)

August 13th, 2011.
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Good Afternoon and welcome to a very brief tropical weather update. My forecasts for all our systems remain unchanged, I just wanted to add that we now have Tropical Storm Franklin, the 6th named storm of the very active Atlantic Hurricane season and that 94L has become tighter defined in the last few hours, that might warrant an increase in the percents to say 40%, but I have my doubts that 94L will become Gert.

(fig 1. Franklin as of this short update)

We'll watch the Atlantic very closely.

CybrTed

Invest 92L and Invest 93L to watch 8/11/11

By: CybrTeddy, 3:19 PM GMT on August 11, 2011

Good morning and welcome to my tropical weather update for Thursday, August 11th, 2011. The tropics are fairly active this morning with two areas of interest to watch, that would be invest 92L and invest 93L currently both far out in the Central Atlantic off the coast of Africa. Both areas of interest have good model support and have a good shot to become Franklin and Gert.

(fig 1. view of Invest 92L and invest 93L)

92L to slowly organize over the coming days.
The first area of interest is 92L, which is west of the Cape Verde islands. 92L has had over the last few days struggling organization due to mostly in part of the high amount of dust that has been getting sucked into the broad circulation, and also appears to have some issues with competing vort maxes, similar to what we saw with Emily. The computer models have been really scatterbrained with 92L, but the ones that do develop 92L develop it north of the islands which is reasonable to me.

(fig 2. View of invest 92L.)

Invest 92L will probably continue in a general WNW-W fashion over the next few days, and it is difficult to say where it will go. I am leaning on a good possibility that 92L will be curved out to sea with only a threat to Bermuda and shipping. That being said it is unwise to make such a prediction this far out, as there are too many variables to watch out for over the coming days. One of those will be that trough that will be emerging off the US Coast, and if it sticks around long enough it will more than likely cause 92L to recurve out to sea without a serious threat to land. This is supported by the GFS & ECMWF, which don't bring this anywhere near the US. It is very rare to get a system already this far north that is not declared to hit the USA, though as I mentioned in my last blog Hurricane Ike achieved it in 2008, but the conditions in the Atlantic are much different than what they where in 2008.

(fig 3. Computer models for 92L as of the latest 12z run.)

The intensity for 92L will probably be determined by the factors behind and ahead of it. The invest behind it, 93L which I will talk about in a moment, could in a few days be strong enough to shear 92L with its outflow if it remains as close by as they are now. I do think there's a good chance 92L will develop into a tropical cyclone, but will do so more than likely north of the islands and remain generally weak, with a outside possibility of this becoming a hurricane. Does that mean it won't become a hurricane? No, it could happen but I just don't see it at this time.

(fig 4. Latest computer models for invest 92L.)

Invest 93L could become Franklin first.
The invest behind 92L, invest 93L has been holding up well since it emerged off Africa yesterday. There are deep pockets of -70C near the center of circulation. However, the center of circulation appears to be exposed to the east of the convection. This is quite common for this to happen, as there is some shear off Africa that is causing this. Several of the waves last year that developed did something similar to this, and I don't see how this will be any different at this time.

(fig 5. Satellite image of invest 93L.)

The track forecast is just as uncertain as 92L, but in my opinion 93L has a greater chance of effecting land. The GFS has been consistently making 93L into a very powerful hurricane but has a northward bias, moves it out to sea just like 92L. While that certainly may happen, I am leaning on it moving towards the islands the next few days. The models are showing a bend towards the W-WSW as it moves west the next few days. I think it is very possible 93L will beat 92L to Franklin and could become a powerful hurricane over the next week or so. We're getting into that time of year that this can happen, even the slowest years see major Cape Verde hurricanes and this will be the case this year.

(fig 6. Latest computer model predictions on track.)


(fig 7. Latest intensity model predictions on intensity for 93L.)

We shall see what happens!

CybrTed

Invest 92L and 2nd tropical wave a threat down the road 8/10/11

By: CybrTeddy, 3:48 PM GMT on August 10, 2011

Good morning and welcome to my tropical weather update for Wednesday, August 10th, 2011. The tropics are fairly quiet today with the exception of just off Africa, where our main focus is going to be the next coming days. Right on cue, the tropical Atlantic is finally getting active and I expect our first real threats and first big storms will start appearing too. We're getting in that time where we watch off Africa for major hurricanes, and we could be talking about our first two trouble makers. Currently, we have invest 92L just to the west of the Cape Verde islands which is already far up in latitude and we have a second yet numbered tropical wave emerging behind 92L, both have a good chance to develop into a tropical cyclone over the next few days.

(fig 1. Satellite image of the two tropical waves)

Invest 92L & Tropical Wave model predictions.
The two most aggressive with 92L are the GFS and ECMWF, which are arguably the two top global models. The latest 06z GFS (the 12z GFS just started running during this post) shows 92L becoming a tropical cyclone around 50W or so then moving out to sea. The 06z GFS is showing that once again a quick-to-move trough will be located off the US coast so this situation will be very tricky to predict. It all comes down to timing. Then we have our other tropical wave behind it, which I suspect if not expect will be 93L before too long. This wave is very vigorous, probably the strongest all year, and is much more south than 92L. This wave as shown by the GFS will be forced at first more west due to a building ridge then forced out to sea by a weakness in said ridge.

(fig 2. 06z GFS 102 hours out.)

The 00z ECMWF isn't as aggressive as usual as the GFS, which seems to be a reoccurring theme with the ECMWF so far this year. The 00z ECMWF shows 92L gradually attempting to develop before unwinding and turning out to sea. However what is noticeable about this because it keeps it more west than the GFS does, but still sends it well on its way out to sea between Bermuda and the US. The 2nd wave behind it also is shown to be heading more west at the end of the run, and might not recurve as quickly as shown as on the GFS.

(fig 3. 00z ECMWF 120 hours out.)

The CMC and NOGAPS are very scatterbrained about this situation, both have developed 92L and the wave behind it into a powerful tropical cyclone but have dropped it the next run, this is telling me that the two models are not picking up on something the ECMWF and GFS is. Regardless, in the past they have shown this system taken a path similar to that of what the ECMWF and GFS show, which favors recurving out into sea.

My personal predictions.
As always, predicting where a system will go is very difficult. The trough that the models are showing will steer 92L out to sea is going to be short to stay and might miss 92L. However, I personally believe at this time it is very likely 92L will miss the USA, because of its current latitude already is fairly high. It is very rare to get a system that far north already to hit the United States, Ike was the only exception that I can think of and that was because the ridging was so strong that it forced Ike SW north of the islands. That being said, the 2nd wave I am not so sure of. Last year when we had Hurricane Danielle and Hurricane Earl, the trough that forced Danielle out to sea moved out and forced a ridge over Earl, which caused Earl to move more westward and become a much more powerful and dangerous storm.

(fig 4. Latest track runs on 92L.)

In track, this might be similar to that as you have the first storm being effected by a trough and moving out to sea and then you have the 2nd storm which is forced more westward by ridging then moves out to sea from another trough that emerges off the coast. The models are very confused about this situation, so I refuse to put much stalk in track until either system actually develops into a tropical cyclone. Intensity is just as tricky, but it is possible that one if not both of these systems could become long tracking Cape Verde hurricanes. We're in that time of year like I said where that happens, and we must be vigilent. The pattern in place so far is similar to that of 2008, and we could see strikes this year. Not saying we will, as every year we could see strikes.

We will watch this situation as it unfolds very closely.

CybrTed

Annoying Emily rises from the dead, time to watch off Africa 8/6/11

By: CybrTeddy, 9:00 PM GMT on August 06, 2011

Good afternoon everyone and welcome to my tropical weather update for Saturday, August 6th, 2011. I've been reluctant to do a blog update on Emily mostly because Emily has had no real change in organization and died over Hispaniola. Now Emily has re-generated into a barely-TD off the coast of Florida. Tropical Depression Emily is located at 26.9°N 78.1°W, maximum sustained winds are at a low 30mph and pressures are at a high 1012mb. I won't talk much about Emily, but I'll give a short forecast. Emily is embedded in an area of abnormally high surface pressures, causing winds to also be very weak. Emily is being impeded by moderate wind shear and dry air plus its small size should limit any real intensification. I do not expect Emily to go past a 40mph TS again, and in all likelihood Emily will probably never become a Tropical Storm again. Emily is under the influence of a sharp and well pronounced weakness that will cause her to turn out to sea with no threats to land.
...EMILY REGENERATES AS A WEAK TROPICAL DEPRESSION...EXPECTED TO MOVE AWAY FROM THE BAHAMAS AND THE U.S. COAST SUNDAY...
5:00 PM EDT Sat Aug 6
Location: 26.9°N 78.1°W
Max sustained: 30 mph
Moving: N at 8 mph
Min pressure: 1012 mb


(fig 1. Tropical Depression Emily as of this blog update.)

Time to watch off Africa.
It is that time of year again where we have to watch off Africa for cyclone development and sure enough, models are starting to kick off trouble there. The GFS has been the most aggressive with this, and in the long range is showing a disturbing pattern beginning to take shape. The GFS has been showing in the very long range multiple hurricanes striking the USA, a pattern that is very possible. This is no 2010, the way the ridge over the USA is positioned is very similar to that of seasons that have featured us landfalls, most recently 2008. The NOGAPS also brews up trouble off Africa, and it appears that our next storm may be forth coming.

(fig 2. Hurricane season chart, we are getting close to peak season.)

Regarding a possible storm, it could be the tropical wave that is emerging off Africa. ASCAT revealed a well defined close low level circulation (something of note, Emily has lacked throughout its life time), but none of the models show this wave becoming really defined until later if at all. It is starting to appear to me it is a wave currently centered near the coast of Africa.

(fig 3. Tropical waves worth watching.)

CybrTed

Emily in the Eastern Caribbean 8/2/11

By: CybrTeddy, 4:43 PM GMT on August 02, 2011

Good afternoon and welcome to my tropical weather update for Tuesday, August 2nd, 2011. The tropics remain active as we're talking about Tropical Storm Emily, the 5th named storm of the season. Here's a few statistics about Emily before I begin my analysis. Emily is the 5th named storm of the season, Emily's formation on August 1st marked the most active early half of hurricane season since 2005 and puts us well on pair with the 1933 Atlantic hurricane season. This is likely a sign of what is to come, and increased activity is very likely over the next few weeks. All in all, it is probable we will close out the month with Harvey, similar to 2008. Now, onto my analysis of Emily. Emily is currently located at 15.3°N 63.6°W, maximum sustained winds remain at 40 mph and Emily has suddenly slowed to a halt, was at 16 mph at the last advisory however at 11 am it stalled out, likely signalling a COC relocation to the deeper convection. Satellite presentation has remarkably improved since yesterday, but still does not signal a well organized Tropical Storm as of yet.

(fig 1. Tropical Storm Emily as of this update)

Intensity forecast for Emily.
It comes as no surprise as Hispaniola is in the way that the intensity forecast for Emily is highly uncertain. I've seen strong systems nearly completely croak interacting with Hispaniola, thanks to the high mountains that cause the circulation to become disrupted. Right now I see gradual intensification over the next few days too, given that there is dry air being sucked into the circulation of Emily. Shear does not appear to be a significant problem, as Emily has a Upper-Level Anti-cyclone ahead that is helping channeling outflow. Also, the heat rising rapidly to the surface under Emily is allowing for strong convection to be present. I suspect Emily will become a 60 mph Tropical Storm before it hits Hispaniola and weakens, after that it could weaken to a depression. There is a possibility Emily could completely die over Hispaniola too.

(fig 2. Uncertain intensity models, weakening is shown due to land interaction with Hispaniola)

After it crosses Hispaniola it is difficult to suspect how strong Emily might get. It Hispaniola serves to only slightly disrupt the circulation it is probable that Emily will become a hurricane. If it completely destroys the circulation, I highly doubt Emily will obtain hurricane status.

Track forecast for Emily.
As always, the track forecast is dependent on the intensity forecast for Emily. If Emily strengthens more than anticipated it will feel the weakness that has been developing to the north due to a trough, and will be tugged northward by that trough and well out to sea. If Emily however remains weak, like what the ECMWF and CMC is showing once it crosses Hispaniola it will likely be not so keen to feel the influence from that trough and be forced more westward over the coming days. Right now it appears that if there will be a US landfall it appears that Florida is the most at risk from this system approaching and or making landfall. Right now Florida is well in the cone, but the track is very uncertain. Several models show Emily skiving off towards the NE and out to sea, and some show it making it into the Gulf of Mexico. It is highly uncertain if this will verify.

(fig 3. Latest forecast track)

As always, we shall see what happens!

CybrTed

SPECIAL UPDATE Tropical Storm Emily finally develops 8/1/11

By: CybrTeddy, 11:55 PM GMT on August 01, 2011

Good evening and welcome to my SPECIAL tropical weather update for Monday, August 1st, 2011. We finally have Tropical Storm Emily, which was sitting at 80-100% chance of development on the NHC site for a few days. 91L had a problem with multiple competing vorticies, but today has finally decided that it wanted to use just one, west of Dominica, and that is the primary circulation. Emily is still disorganized, but is becoming better organized as the hours go by. It is finally showing much deeper convection, around -80C, over and around its COC but has nothing on the western semi-circle. This is indicative of shear still inhibiting development. Another factor is the fact the humidity is so low in Emily, 50%, which tells us that dry air is intruding still the circulation. Based on this, I expect gradual organization.


(fig 1. Tropical Storm Emily, the 5th named storm of the season.)

My early predictions.
The models, especially compared to the last three storms, have done a fairly good job at predicting Emily's formation. All of the models show at this time Emily making landfall in Hispaniola, and showing weakening as it does so. I would not be surprised if the interaction with land from Emily is so great that it weakens to TD status, but should intensify as it enters over the Bahamas. There is a possibility that it could strengthen enough to become a hurricane. Also, another factor is sometimes the friction with Hispaniola causes storms to strengthen briefly. I saw this with Olga in 2007, and Fay in 2008. There is a possibility that could happen.

(fig 2. First forecast track on Emily)

The track also relies on the intensity predictions, Emily could decide that it wants to become stronger than predicted and then more likely to feel the influence from the trough and move out to sea. It is possible that Emily decides to stay weak then intensity as it nears Florida. Emily appears to be bound to follow a trough split and head in that way, so I think that Emily will at least approach Florida, if not make landfall on Saturday.

We will follow this VERY closely.

CybrTed


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