92L Poised to Develop in Gulf of Mexico; Erin Struggling in Far Eastern Atlantic

By: Dr. Jeff Masters , 2:09 PM GMT on August 16, 2013

Tropical wave 92L crossed over Mexico's Yucatan Peninsula overnight, and the center of the disturbance is now located in the Gulf of Mexico along the west coast of the Yucatan Peninsula. Satellite loops show that 92L has a well-developed surface circulation, but there are no heavy thunderstorms near the center. A moderate-sized region of heavy thunderstorms does lie to the northeast and east of the center, over Cancun, Cozumel, and southwards to Belize. An upper-level low pressure system over the Gulf of Mexico is pumping dry air into 92L, slowing development. Wind shear is a moderate 10 - 20 knots over the the wave, which should allow slow development today. The hurricane hunter flight scheduled for today has been cancelled.


Figure 1. MODIS satellite image of 92L taken at 1:30 pm EDT Friday August 16, 2013. Image credit: NASA.

Forecast for 92L
The 12Z Friday SHIPS model forecast predicts that 92L will remain in an area of low to moderate wind shear through Saturday, and ocean temperatures will be a favorable 29 - 30°C. The topography of the Southern Gulf of Mexico's Bay of Campeche can aid in getting a storm spinning more readily, as well. Given these favorable conditions for intensification, 92L should be able to become a tropical depression by Saturday, and a tropical storm by Sunday. A trough of low pressure over the northern Gulf of Mexico will dip down by Sunday over the Central Gulf of Mexico, increasing the wind shear to a high 20 - 30 knots just to the north of 92L. This trough may also be able to pull the storm northwestwards to a landfall in Texas on Monday or Tuesday, as the 00Z Friday runs of UKMET and NAVGEM model predict. If 92L does follow this more northwesterly path, intensification into a strong tropical storm would be difficult, due to the high wind shear. An alternate scenario is presented by our two top-performing models, the European and GFS. They predict that 92L will take a nearly due west track, resulting in a landfall south of Tampico, Mexico on Monday. The storm would have more of an opportunity to strengthen in this scenario, since wind shear would be lower. Either scenario is reasonable, and residents of the Mexican and Texas Gulf Coast should anticipate the possibility of a tropical storm hitting the coast as early as Sunday night. Regardless of 92L's track, a flow of moist tropical air along the storm's eastern flank will form an atmospheric river of moisture that will bring a wide swath of 4+ inches of rain to the Gulf Coast from Louisiana to the Florida Panhandle over the next few days. In their 8 am EDT Wednesday Tropical Weather Outlook, NHC gave 92L a 50% of developing by Sunday, and a 60% chance of developing by Wednesday. I put these odds higher, at 70% and 80%, respectively.


Figure 2. MODIS satellite image of Tropical Depression Erin taken at 10:30 am EDT Friday August 16, 2013. At the time, Erin had maximum sustained winds of 35 mph. Image credit: NASA.

Tropical Storm Erin
Tropical Storm Erin is over the far Eastern Atlantic off the coast of Africa, and continues west-northwest at 15 mph. Erin is small and weak and has lost nearly all of its heavy thunderstorms, as seen on satellite loops. This is probably due, in part, to the fact the storm is over waters of 25.5 - 26°C, which is a marginal temperature for tropical cyclones. Erin is also having trouble with dry air from the Saharan Air Layer (SAL), and the storm's west-northwest motion is beginning to cut Erin off from a moist source of air to its south--the semi-permanent band of tropical thunderstorms called the ITCZ (Inter-Tropical Convergence Zone.) The latest 00Z runs of the major global computer models, except for the GFS, call for Erin to dissipate by early next week. Given Erin's struggles today, I expect the storm will be dead by Sunday.

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: 1691 - 1641

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50Blog Index

Good Evening Levi and everyone...I think 92L looks better than it did earlier today...looks like it is starting to wrap around....no ?? If not, what am I seeing?
Member Since: Posts: Comments:
Quoting 1584. tropicfreak:
An increase in convective activity was probably what brought Erin back up to TS status.

Don`t forget about ship that record 40knots of winds in Erin.
Member Since: Posts: Comments:
Quoting 1664. TampaSpin:
Its very easy to understand why so many people that were better than most on here are no longer posting.


Actually, that I do not understand. There are ways to easily ignore comments that are blatantly "trollish". And a passionate discussion about something, with opposing views is not necessarily a bad thing. Maybe it is a reflection of being able to seek out only those forums where everyone "agrees" with you. I for one, as some can attest here, relish a good passionate discussion as long as it does not devolve into name calling and personal attacks.
Member Since: Posts: Comments:
1688. sar2401
Quoting Levi32:


There's some enhanced surface vorticity there, at least. The movement of the low to the south suggests something's going on in there, but it's hard to see what. We might get an ASCAT pass within the hour.

I sure wish the decision to cancel today's recon flights hadn't been made. We are sitting here, in the literal and figurative darkness, spending a lot of our time trying to figure out exactly where the low is and what kind of circulation exists. At least one recon flight would have been a big help.
Member Since: Posts: Comments:
Quoting 1684. Grothar:


Thanks very much for that. But to be honest I don't have anything else to do.


I mean at your age...
Member Since: Posts: Comments:
1686. flsky
Quoting 1680. Levi32:
The ASCAT pass is already in. Just a trough, it looks like.


I really don't understand why it's spinning where it is in the visual, but it's not represented in the ASCAT. Can you help me with this?
Member Since: Posts: Comments:
1685. beell
LOL, Gro.
Member Since: Posts: Comments:
1684. Grothar
Quoting 1673. sporteguy03:


Very true Gro! There are plenty of bloggers on here including yourself who likes to point out blobs to watch. This blog is valuable because bloggers provide information that many sites charge a premium for. It is not expected, but it is nice to see that you and so many take the time out of your day to post and provide thoughts on the tropics.


Thanks very much for that. But to be honest I don't have anything else to do.
Member Since: Posts: Comments:
Quoting 1676. sar2401:

Surge is a function mostly of pressure, wind and forward motion. 92L'a pressure is barely low, the wind speed is maybe 25 knots, and the forward speed, even if goes north, which I doubt, will still be very slow. Unless this thing somehow turns into a hurricane, I can't imagine surge being an issue


You're wrong there, a low sitting off the coast moving slowly can do lot's of surge as the winds continually pile up the water along the coast. Look at Nor'Ida as the best example of that.
Member Since: Posts: Comments:
1682. flsky
Quoting 1655. DonnieBwkGA:
In fact Georgia is so avoided by tropical systems that our flood insurance rates here were just cut by 5% last week. That's in unincorporated Glynn County. We already had the lowest rates on the east coast.

Upon reflection, Florida residents don't want to hear about that do they? :P

Well...we have quite a few years here between storms *knocks on wood* but if you live on a barrier island, forget about rates lowering.
Member Since: Posts: Comments:
1680. Levi32
The ASCAT pass is already in. It looks like just a trough. The anchoring low looks weaker, as well.

Member Since: December 31, 1969 Posts: Comments:
I don't understand why the Shear Maps was so far off with 92L....HECK they was not even close!
Member Since: Posts: Comments:
1678. SRQfl
Some boomers moving into my area tonight courtesy of 92l/ULL/Blob thingy. Has that ULL by the Yucatan gone ANNULAR? I kid, I kid.
Member Since: Posts: Comments:
Atlanta breaks a century-old temperature record Thursday

ATLANTA (CBS ATLANTA) -
Atlanta's high temperature on Thursday was only 73 degrees which is the coolest high temperature on record for August 15.

The previous record was a high of only 77 degrees from 1908.

Thursday's high followed even cooler temperatures on Friday when Atlanta only hit 67 degrees -- the coolest August high temperature since 1986.

The average high temperature for this time of year is 88 degrees, putting Thursday's high 15 degrees below average.

Atlanta has seen a cooler-than-average summer due to a lot of rain. We're about 15 inches above average
on rainfall this year.

Link
Member Since: December 31, 1969 Posts: Comments:
1676. sar2401
Quoting nolamusic:
As slow as this 'thing' in the gulf is moving, are there any surge issues we should be looking for? I only see surge maps when something is named, but this (because of personal proximity to lake and canals) looks like it could push a lot of water ahead of it?

Surge is a function mostly of pressure, wind and forward motion. 92L's pressure is barely low, the wind speed is maybe 25 knots, and the forward speed, even if goes north, which I doubt, will still be very slow. Unless this thing somehow turns into a hurricane, I can't imagine surge being an issue
Member Since: Posts: Comments:
1675. Levi32
Quoting 1660. TropicalAnalystwx13:
It's interesting to see how close the 12z and 18z GFS runs are for a forecast 16 days out.

The intensities for the two storms flopped, but they're almost in the exact same location.




I think you will see the majority of GFS runs look like that with 1 or 2 Cape Verde storms in each forecast for the next 4 weeks or so.
Member Since: December 31, 1969 Posts: Comments:
1674. scott39
Quoting 1671. Levi32:


There's some enhanced surface vorticity there, at least. The movement of the low to the south suggests something's going on in there, but it's hard to see what. We might get an ASCAT pass within the hour.
Thank you
Member Since: Posts: Comments:
Quoting 1579. Grothar:


Read back, Levi. You get plenty of support and you know people respect and admire your efforts. I would never have the time or the patience to do those videos and neither does anyone else. We just enjoy the debates between you two. A lot of people respect Drak, too.


Very true Gro! There are plenty of bloggers on here including yourself who likes to point out blobs to watch. This blog is valuable because bloggers provide information that many sites charge a premium for. It is not expected, but it is nice to see that you and so many take the time out of your day to post and provide thoughts on the tropics.
Member Since: Posts: Comments:
Quoting 1667. flsky:

I imagine they still lurk.


NOPE....most left this blog.
Member Since: Posts: Comments:
1671. Levi32
Quoting 1656. scott39:
Do you see possible developement of a relocated LLC to the NE?


There's some enhanced surface vorticity there, at least. The movement of the low to the south suggests something's going on in there, but it's hard to see what. We might get an ASCAT pass within the hour.
Member Since: December 31, 1969 Posts: Comments:
Quoting 1658. redwagon:


Are you seeing the second split with 92L?


I'm not really sure there is a split or if the center has relocated. Or what. Just hope it keeps enough moisture to rain if it comes west.
Member Since: December 31, 1969 Posts: Comments:
1669. Grothar
Quoting 1655. DonnieBwkGA:
In fact Georgia is so avoided by tropical systems that our flood insurance rates here were just cut by 5% last week. That's in unincorporated Glynn County. We already had the lowest rates on the east coast.

Upon reflection, Florida residents don't want to hear about that do they? :P


I actually pay more for our home insurance in one year than I did on the purchase of our first home.
Member Since: Posts: Comments:
1668. KEEPEROFTHEGATE (Mod)
Member Since: Posts: Comments:
1667. flsky
Quoting 1664. TampaSpin:
Its very easy to understand why so many people that were better than most on here are no longer posting.

I imagine they still lurk.
Member Since: Posts: Comments:
1666. Jerrob
Quoting 1655. DonnieBwkGA:
In fact Georgia is so avoided by tropical systems that our flood insurance rates here were just cut by 5% last week. That's in unincorporated Glynn County. We already had the lowest rates on the east coast.

Upon reflection, Florida residents don't want to hear about that do they? :P
no...no we dont :)
Member Since: Posts: Comments:
1665. flsky
Quoting 1651. ProgressivePulse:
92L is tandem with a ULL, nothing new there. Erin was DOA. Wave at 45W is looking spunky, It's obvious the Atlantic is wanting to release some energy, worth a look anyways. Not sure the number next in cue but I would say we will have another invest soon.

At the surface



Shear



Satellite


Is the ITCZ ever going to lift??
Member Since: Posts: Comments:
Its very easy to understand why so many people that were better than most on here are no longer posting.
Member Since: Posts: Comments:
5 yards from previous spot, replay 2nd down.
Member Since: Posts: Comments:
Quoting 1604. GTstormChaserCaleb:
The NAM joins the CMC for development of the area of disturbed weather associated with the monsoon trough between 45-50 West.





The two most reliable models we have..lol, Now lets see if the Euro or GFS starts jumping aboard
Member Since: Posts: Comments:
It's interesting to see how close the 12z and 18z GFS runs are for a forecast 16 days out.

The intensities for the two storms flopped, but they're almost in the exact same location.


Member Since: Posts: Comments:
Quoting 1655. DonnieBwkGA:
In fact Georgia is so avoided by tropical systems that our flood insurance rates here were just cut by 5% last week. That's in unincorporated Glynn County. We already had the lowest rates on the east coast.

Upon reflection, Florida residents don't want to hear about that do they? :P


Dude, LA residents don't want to hear it either. But, good for you! I had no idea they were going down anywhere.
Member Since: Posts: Comments:
Quoting 1653. AtHomeInTX:
GMZ001-171430-
SYNOPSIS FOR THE GULF OF MEXICO
1017 PM EDT FRI AUG 16 2013

.SYNOPSIS...LOW PRESSURE LOCATED NEAR 21N91.5W IS FORECAST TO
BEGIN TO MOVE NW TONIGHT REACHING NEAR 22N94W LATE SAT AND NEAR
25N95W LATE SUN...THEN MOVING INLAND THE EXTREME SE TEXAS COAST
LATE MON...WITH THE POSSIBILITY OF TROPICAL CYCLONE FORMATION
THROUGH MON. A RIDGE WILL DOMINATE THE REMAINDER OF THE GULF
THROUGH THE PERIOD.


Are you seeing the second split with 92L?
Member Since: Posts: Comments:
Quoting 1555. Levi32:
It's actually pretty funny how little support I get from the blog when I'm not forecasting the scenario that would bring the worst weather to the US. Hey, we'll see what happens. I believe tropical forecasting is one of the greatest competitions there is.
I have noticed that. Some seem like they feel its a bust if there is no destruction. I get jacked up also, I get ready early, but Im happy if they fall apart.
Member Since: Posts: Comments:
1656. scott39
Quoting 1645. Levi32:
The models are already towards southern Texas. They can't "shift back" there. Their previous forecast was New Orleans or eastward.

Do you see possible developement of a relocated LLC to the NE?
Member Since: Posts: Comments:
1654. Patrap
Oooh, "Neutral Zone infraction",

...no,never say they can't shift back in the August GOM




Member Since: December 31, 1969 Posts: Comments:
GMZ001-171430-
SYNOPSIS FOR THE GULF OF MEXICO
1017 PM EDT FRI AUG 16 2013

.SYNOPSIS...LOW PRESSURE LOCATED NEAR 21N91.5W IS FORECAST TO
BEGIN TO MOVE NW TONIGHT REACHING NEAR 22N94W LATE SAT AND NEAR
25N95W LATE SUN...THEN MOVING INLAND THE EXTREME SE TEXAS COAST
LATE MON...WITH THE POSSIBILITY OF TROPICAL CYCLONE FORMATION
THROUGH MON. A RIDGE WILL DOMINATE THE REMAINDER OF THE GULF
THROUGH THE PERIOD.
Member Since: December 31, 1969 Posts: Comments:
1652. scott39
Quoting 1632. sar2401:

I have no clue what's going on with 92L. Assuming the putative low is at about 23N, 90.5W, it has not moved in about 10 hours. It continues to send out tropical waves to the northeast, which is the convection we're seeing. I see no evidence that low is moving at all, let alone toward the area of convection. Given the weak steering currents and the location of the low in the BOC, which known for keeping lows spinning, the low may just sit there for the next 24-36 hours, sending of more waves of convection toward the Florida Panhandle, which is really the worst case scenario right now. If the low could finally get moving, it would go straight west right at the MC/TX border, bringing some much needed rain but nothing more than a TD. If, for some reason, the low actually begins to move northeast, it has no chance for development, but it can provide enough energy for three days of rain for the Panhandle and south Alabama before it finally comes ashore. The best ending for all concerned is for this low to get moving west and cut off the moisture fetch.
This was not my idea. Got it from a seasoned blogger from the past. Like yourself, I have no clue. Only time will tell on this odd invest.
Member Since: Posts: Comments:
92L is tandem with a ULL, nothing new there. Erin was DOA. Wave at 45W is looking spunky, It's obvious the Atlantic is wanting to release some energy, worth a look anyways. Not sure the number next in cue but I would say we will have another invest soon.

At the surface



Shear



Satellite

Member Since: Posts: Comments:
1650. sar2401
Quoting Boco12:
This is quite an interesting setup in the WPAC right now
Tropical Depression 12:


and Tropical Depression 13:


If these forecasts are to verify, we would see the Fujiwhara effect go into full force. Especially if the proximity between the two storms will be less than a couple hundred miles with both at category one intensity.

It will be very interesting to watch if this comes to pass, They will almost be too close to one another. They should merge or the stronger storm shear out the weaker storm very rapidly. The one thing I'm not clear about is whether merger means one stronger storm. I've seen it where the merged storms simply become larger, but not stronger. Maybe someone who's smarter than me knows the answer.
Member Since: Posts: Comments:
1649. HadesGodWyvern (Mod)
Member Since: December 31, 1969 Posts: Comments:
1648. HadesGodWyvern (Mod)
Philippines Atmospheric Geophysical Astronomical Services and Administration
Tropical Cyclone Bulletin #2
TROPICAL DEPRESSION MARING
11:00 AM PhST August 17 2013
============================

Tropical Depression "MARING" has slightly accelerated as it moves in east southeast direction

At 10:00 AM PhST, Tropical Depression Maring (1000 hPa) located at 21.3N 124.7E or 270 km northeast of Itbayat, Batanes has 10 minute sustained winds of 30 knots. The depression is reported as moving east southeast at 6 knots.

Additional Information
=======================
Publis Storm Warning Signal no. 1 over Batanes group of Islands has been lifted.

Estimated rainfall amount is from 5-10 mm per hour (moderate to heavy) within the 300 km diameter of the tropical depression.

"MARING" is expected to enhance the Southwest Monsoon which will bring light to moderate rainshowers and thunderstorms over western section of northern and central Luzon.

The public and the disaster coordinating councils concerned are advised to take appropriate actions and watch for the next bulletin to be issued at 11 PM today.
Member Since: December 31, 1969 Posts: Comments:
1647. Patrap
Mojo afloat

Member Since: December 31, 1969 Posts: Comments:
Quoting 1641. Patrap:


OOoh, pinhole eye?

sarcasm: ON
Chad Myers was right. Eye looks explosive.
Member Since: Posts: Comments:
1645. Levi32
The models are already towards southern Texas. They can't "shift back" there. Their previous forecast was New Orleans or eastward.

Member Since: December 31, 1969 Posts: Comments:
1644. Grothar
Quoting 1637. DonnieBwkGA:


With whom?

We are on the southern edge of an isentropic ascent rain shield. I think I am within spitting distance of the front.


At this point, anybody.
Member Since: Posts: Comments:
The tropical wave moving off the African coast sort of reminds me of pre-Igor 2010, with the two-component kind of thing.

Member Since: Posts: Comments:
Quoting 1629. Boco12:
This is quite an interesting setup in the WPAC right now
Tropical Depression 12:


and Tropical Depression 13:


If these forecasts are to verify, we would see the Fujiwhara effect go into full force. Especially if the proximity between the two storms will be less than a couple hundred miles with both at category one intensity.
I have never seen the fujiwhara effect like that.I've seen it east to west,not north to south or south to north.
Member Since: Posts: Comments:
1641. Patrap


OOoh, pinhole eye?

sarcasm: ON
Member Since: December 31, 1969 Posts: Comments:

Viewing: 1691 - 1641

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50Blog 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