Tropical Storm Emily

[Randall Marable]

As we watch Tropical Storm Don approach Southern Texas and Northern Mexico, all attention will soon turn to newly declared Invest 91L in the Central Atlantic. It has the NHC's attention as of now since now we have a Code Orange...



TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 AM EDT FRI JUL 29 2011

1. A LARGE TROPICAL WAVE ACCOMPANIED BY A WELL-DEFINED LOW PRESSURE
SYSTEM IS LOCATED ABOUT 1200 MILES EAST-SOUTHEAST OF THE LESSER
ANTILLES. THIS DISTURBANCE IS SHOWING SIGNS OF ORGANIZATION...AND
ENVIRONMENTAL CONDITIONS ARE CONDUCIVE FOR GRADUAL DEVELOPMENT OVER
THE NEXT FEW DAYS. THIS SYSTEM HAS A MEDIUM CHANCE...30 PERCENT...
OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES
WESTWARD OR WEST-NORTHWESTWARD AT 15 TO 20 MPH.

 

[Randall Marable]

The 00Z GFS has this system moving through the Windward Islands late Monday evening heading toward the northwest.

 

[Paul Stofer]

The last few frames of the satellite loop of 91L you can see a low level circulation associated with it.

 

[Stuart Robinson]

General agreement in the 06Z models that 91L will become Hurricane Emily in 48 hours time. (TS Emily within 24 hours)

 

[MClarkson]

I like the very solid upper level anticyclone the GFS has progged north of the island chain in 3-4 days or so. A little surprised the 31/00Z HWRF or 30/18Z GFDL don't have a stronger system. SSTs look like they are in the 83-84F range. The system is not remotely organized as of Saturday night but it still has time...

 

[Ari Brown]

Hurricane Hunters are nearly into 91L, and I think we'll see TD 5 or TS Emily as soon as they find the LLC and verify its closure. Anybody in the northern Lesser Antilles as well as Puerto Rico and Hispaniola need to watch this system, and watches/warnings will likely be posted as soon as 91L becomes 05L. Most of the models are indicating a direct hit on PR and then tracking just off the northern coast of the Dominican Republic and perhaps into the Bahamas.

 

[MClarkson]

Tonights GFS has the upper level anticyclone and surface low near the east coast of FL in about 6 days after tracking right along the islands. The ECMWF has the upper level high in about the same place, but is not resolving the surface low. The nested hurricane models are starting to look a little more interesting. I'll be keeping an eye on this one... slight chance of a chase worthy target next weekend?

 

[Warren Faidley]

Tonights GFS has the upper level anticyclone and surface low near the east coast of FL in about 6 days after tracking right along the islands. The ECMWF has the upper level high in about the same place, but is not resolving the surface low. The nested hurricane models are starting to look a little more interesting. I'll be keeping an eye on this one... slight chance of a chase worthy target next weekend?

Yes!

The latest Early Cycle Track Guidance Ensembles have moved the system much further towards the NW, now making the eastern portions of Florida, or anywhere along the eastern coast a possible target in (+/-) 120 hours. In addition, 2 of the 10 intensity models are forecasting Cat 4 intensity, with two others forecasting Cat 2.

Reference: http://euler.atmos.colostate.edu/~vigh/guidance/

Of more interest, is the latest GFS, which shows a tropical cyclone impacting south Florida
this coming Saturday. The GFS was fairly accurate last year dealing with tropical weather in the 120 hour range.

I'll likely wait another 24 hours before I start the deployment process.

Cheers:

Warren

 

[Ari Brown]

Well, the USAF recon mission has just confirmed TS winds and a fully closed surface circulation with 91L, meaning that we'll probably get a special advisory to start off TS Emily shortly. No renumber on ATCF yet, as I'd imagine the NHC is currently scrambling to notify the meteorological agencies with affected jurisdictions, as TS force winds will be impacting the northern Leewards very shortly.

Right now models are pointing towards Florida and the Bahamas. I'd say everyone from FL and the Bahamas north needs to keep a close eye on this one.

I'll post the ATCF renumber and initial intensity when it's available.

 

[Randall Marable]

Here it is...

BEGIN
NHC_ATCF
invest_al052011.invest
FSTDA
R
U
040
010
0000
201108012219
NONE
NOTIFY=ATRP
END
EMILY, AL, L, , , , , 05, 2011, DB, O, 2011072900, 9999999999, , , , , , WARNING, 1, AL052011
[snip]
AL, 05, 2011080118, , BEST, 0, 151N, 605W, 30, 1006, LO, 34, NEQ, 0, 0, 0, 0, 1011, 150, 60, 0, 0, L, 0, , 0, 0, EMILY, M,

 

[Randall Marable]

Hey Mods can we get the thread title updated? Thanks.

 

[Ari Brown]

Here it is...

Thanks. Here's the first advisory from the NHC:

BULLETIN
TROPICAL STORM EMILY SPECIAL ADVISORY NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL AL052011
730 PM AST MON AUG 01 2011

...NEW TROPICAL STORM FORMS...TROPICAL STORM WATCHES AND WARNINGS
ISSUED...


SUMMARY OF 730 PM AST...2330 UTC...INFORMATION
----------------------------------------------
LOCATION...15.2N 62.0W
ABOUT 50 MI...80 KM WSW OF DOMINICA
ABOUT 350 MI...565 KM SE OF SAN JUAN PUERTO RICO
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...W OR 275 DEGREES AT 17 MPH...28 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES

......
SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* DOMINICA
* GUADELOUPE...DESIRADE...LES SAINTES...AND MARIE GALANTE
* PUERTO RICO...VIEQUES AND CULEBRA
* THE DOMINICAN REPUBLIC

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* U.S. VIRGIN ISLANDS
* ST. KITTS...NEVIS...MONSTSERRAT...AND ANTIGUA
* HAITI

NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...1100 PM AST.

$$
FORECASTER BRENNAN

The only good news here is that Emily will run over Hispaniola, which usually upsets the core of and weakens a tropical storm. Hopefully 4-6" of rain won't be enough to trigger mass mudslides in Haiti and the Dominican Republic.

 

[Randall Marable]

I'm not surprised with this discussion. Hopefully now that we have a center of circulation at the moment, the model spread will decrease in the long term...


THE LOW-LEVEL CIRCULATION HAS BEEN MOVING QUICKLY WESTWARD...AND THE
INITIAL MOTION ESTIMATE IS A HIGHLY UNCERTAIN 275/15. EMILY IS
CURRENTLY SITUATED TO THE SOUTH OF A WEAKENING MID-LEVEL RIDGE OVER
THE SUBTROPICAL WESTERN ATLANTIC. THE GLOBAL MODELS ARE IN
GENERALLY GOOD AGREEMENT SHOWING THIS RIDGE WEAKENING OVER THE NEXT
COUPLE OF DAYS AS A MID-LEVEL TROUGH DIGS SOUTHWARD OVER THE
WESTERN ATLANTIC. THIS SHOULD ALLOW EMILY TO TURN
WEST-NORTHWESTWARD AND SLOW DOWN A LITTLE IN THE FIRST 48 HOURS.
BEYOND THAT TIME...THE TRACK FORECAST IS HIGHLY UNCERTAIN AND
DEPENDS ON WHAT SHAPE EMILY IS IN AFTER IT MOVES PAST HISPANIOLA
AND HOW MUCH THE RIDGE RE-BUILDS TO THE NORTH OF THE CYCLONE OVER
THE WESTERN ATLANTIC TOWARD THE END OF THE PERIOD. THERE IS QUITE A
BIT OF SPREAD IN THE TRACK MODEL GUIDANCE...WITH THE ECMWF TAKING A
WEAKER CYCLONE FARTHEST TO THE WEST SHOWING A TRACK NEAR SOUTHERN
FLORIDA...WHILE THE GFDL AND THE NEW 18Z GFS ARE FARTHEST TO THE
RIGHT WITH A TRACK NEAR OR EAST OF THE BAHAMAS.

 

[cdcollura]

Good day all,

Florida loves to be in the "Cone of Uncertainty".

It's a very far-fetched forecast this far out (120 hours). If this track verifies, one MAJOR hurdle would be the 9,000+ foot mountains in Haiti / Dominical Republic (Hispanola) in the Wednesday (8-3) or so time-frame.

It is unlikely Emily will survive that passage without major disruption to the LLC (or even dissipation). Another probability is crossing SW of Mainland Haiti and east of Cuba and emerging in the SE Bahamas / FL Straits in 96 hours or so. With the re-building high to the north and light shear / warm waters, insensification should resume, right about the time Emily nears Florida as a hurricane (possibly).

If FL / any Gulf State gets hit with a hurricane, this will be the first time a hurricane hit the US since September 2008 (Ike in TX), nearly 1100 days ago!

 

[Mike Moore]

Models shifting back East a tad... but wig wag is to be expected this early in the game. I'll be interested to see where we are once it clears Hispaniola.