Subtropical Depression TEN

[Somerset Squall]

Subtropical Depression Ten has formed in the eastern GOM. It's forecast to parrallel the coast and may strengthen a little over the next couple of days, but I would imagine proximity to land will halt any major intensification, along with the fact that organistion is very poor at the moment. Will probably be a rain maker more than anything.

SUBTROPICAL DEPRESSION TEN DISCUSSION NUMBER 1

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL102007

1100 AM EDT FRI SEP 21 2007

CONVECTION ASSOCIATED WITH THE NON-TROPICAL LOW IN THE GULF HAS

GRADUALLY BECOME BETTER ORGANIZED SINCE YESTERDAY...WITH A

WELL-DEFINED BAND IN THE EASTERN SEMICIRCLE AND INTERMITTENT

CONVECTION CLOSER TO THE CENTER. ALTHOUGH THE AMOUNT OF CONVECTION

PRESENT PROBABLY STRAINS THE DEFINITION A BIT...BECAUSE OF THE

POTENTIAL FOR ADDITIONAL DEVELOPMENT RIGHT ALONG THE COASTLINE...

ADVISORIES ARE BEING INITIATED ON SUBTROPICAL DEPRESSION TEN. AN

AIR FORCE RESERVE UNIT RECONNAISSANCE AIRCRAFT FIXED A SMALL

CIRCULATION CENTER A SHORT DISTANCE OFFSHORE OF APALACHICOLA...BUT

BUOY OBSERVATIONS SUGGEST THAT A LARGER-SCALE CENTER MAY BE FARTHER

SOUTH. THE ILL-DEFINED NATURE OF THE SURFACE CIRCULATION...AS WELL

AS THE LINGERING UPPER-LOW ALOFT...PROVIDE THE RATIONALE FOR A

SUBTROPICAL CLASSIFICATION.

THE INITIAL MOTION ESTIMATE IS 325/7. A MID-LEVEL RIDGE OF HIGH

PRESSURE STRETCHING FROM TEXAS NORTHEASTWARD IS EXPECTED TO TURN THE

DEPRESSION TO THE WEST-NORTHWEST ON A TRACK NEARLY PARALLEL TO THE

COASTLINE. MODEL GUIDANCE IS IN GOOD AGREEMENT AND THE OFFICIAL

FORECAST FOLLOWS THE DYNAMICAL MODEL CONSENSUS. BECAUSE THE

FORECAST TRACK IS NEARLY PARALLEL TO THE COASTLINE...A LANDFALL

LOCATION IS DIFFICULT TO PINPOINT...BUT IN ANY EVENT THE CENTER OF A

SUBTROPICAL CYCLONE IS RELATIVELY UNIMPORTANT. MOST OF THE WEATHER

ASSOCIATED WITH THE SYSTEM IS WELL-DISPLACED FROM THE CENTER.

THE UPPER-LOW IS FRAGMENTING...WITH THE MAIN ENERGY SLIDING

SOUTHWEST OF THE DEPRESSION. THIS WILL LEAVE THE DEPRESSION UNDER

LIGHT SOUTHEASTERLY FLOW OVER THE NEXT DAY OR SO. THE FLOW OF

RELATIVELY COOL CONTINENTAL AIR INTO THE GULF AHEAD OF THE

SYSTEM...AS WELL AS ITS POOR ORGANIZATION...SHOULD PREVENT

EXCESSIVE DEVELOPMENT. THE TROPICAL INTENSITY MODELS ALL SHOW

DEVELOPMENT TO A MID-RANGE TROPICAL STORM...WHILE THE GLOBAL

MODELS...WHICH MIGHT BE MORE APPROPRIATE TO THIS SITUATION...

FORECAST LITTLE STRENGTHENING. THE OFFICIAL FORECAST REPRESENTS A

COMPROMISE AMONG THESE SOLUTIONS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 21/1500Z 29.2N 85.5W 30 KT

12HR VT 22/0000Z 29.7N 86.6W 35 KT

24HR VT 22/1200Z 30.1N 88.1W 40 KT

36HR VT 23/0000Z 30.6N 90.3W 40 KT...INLAND

48HR VT 23/1200Z 31.5N 93.0W 30 KT...INLAND

72HR VT 24/1200Z...DISSIPATED

$$

FORECASTER FRANKLIN

[kold weather]

Well once again I don't have the time for a long in-depth post however this system looks very unorganised in terms of the convective coverage which as the forecast even says may be a little too low to make the classification of a subtropical system...in other words had it been in the deep Atlantic it would still be an invest. Still recon into the system over the last few hours has indeed found flight level winds that may support close to subtropical storm status even with the lowest reduction it would still support 35kts so we may see an upgrade fairly soon IMO.

Track should be now W/WNW with the system tracking close to the coastline, though the main center will likely form further south then where it is currently estimated. Still as the forecast dicussion even said the main weather will be away from the center and even then given the fairly stable atmopshere convection really isn't that strong despite warm waters, though the slow foward movement is helping to give rain to areas that haven't had all that much recently in the SE states.

[Somerset Squall]

Subtropical Depression Ten has become fully tropical as convection establishes itself over the center.

TROPICAL DEPRESSION TEN INTERMEDIATE ADVISORY NUMBER 1A

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL102007

100 PM CDT FRI SEP 21 2007

...DEPRESSION BECOMES TROPICAL...

SATELLITE IMAGERY INDICATES THAT THE SUBTROPICAL DEPRESSION HAS

ACQUIRED ENOUGH TROPICAL CHARACTERISTICS TO BE CONSIDERED A

TROPICAL DEPRESSION.

A TROPICAL STORM WARNING REMAINS IN EFFECT FROM APALACHICOLA FLORIDA

WESTWARD TO THE MOUTH OF THE MISSISSIPPI RIVER...INCLUDING NEW

ORLEANS AND LAKE PONTCHARTRAIN. A TROPICAL STORM WARNING MEANS THAT

TROPICAL STORM CONDITIONS ARE EXPECTED WITHIN THE WARNING AREA

WITHIN THE NEXT 24 HOURS.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...INCLUDING POSSIBLE

INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED

BY YOUR LOCAL WEATHER OFFICE.

AT 100 PM CDT...1800Z...THE CENTER OF TROPICAL DEPRESSION TEN WAS

LOCATED NEAR LATITUDE 29.7 NORTH...LONGITUDE 85.9 WEST OR ABOUT 50

MILES... 85 KM...SOUTHWEST OF APALACHICOLA FLORIDA AND ABOUT 155

MILES...250 KM...EAST-SOUTHEAST OF MOBILE ALABAMA.

THE DEPRESSION IS MOVING TOWARD THE NORTHWEST NEAR 11 MPH. A TURN TO

THE WEST-NORTHWEST IS EXPECTED DURING THE NEXT 24 HOURS. ON THE

FORECAST TRACK...THE CENTER OF THE DEPRESSION WILL BE MOVING NEARLY

PARALLEL TO THE COASTLINE WITHIN THE WARNING AREA TODAY AND

TONIGHT.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/HR...WITH HIGHER

GUSTS. THE DEPRESSION IS EXPECTED TO BECOME A TROPICAL STORM LATER

TODAY OR TOMORROW.

THE MINIMUM CENTRAL PRESSURE REPORTED BY A RECONNAISSANCE AIRCRAFT

WAS 1006 MB...29.71 INCHES.

RAINFALL ACCUMULATIONS OF 2 TO 4 INCHES...WITH ISOLATED MAXIMUM

AMOUNTS OF 6 INCHES...CAN BE EXPECTED IN ASSOCIATION WITH THE

DEPRESSION.

ISOLATED TORNADOES ARE POSSIBLE OVER SOUTHWESTERN GEORGIA...THE

FLORIDA PANHANDLE...AND SOUTHEASTERN ALABAMA THROUGH TONIGHT.

COASTAL STORM SURGE FLOODING OF 1 TO 2 FEET ABOVE NORMAL TIDE LEVELS

CAN BE EXPECTED IN AREAS OF ONSHORE FLOW.

REPEATING THE 100 PM CDT POSITION...29.7 N...85.9 W. MOVEMENT

TOWARD...NORTHWEST NEAR 11 MPH. MAXIMUM SUSTAINED WINDS...35 MPH.

MINIMUM CENTRAL PRESSURE...1006 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL

HURRICANE CENTER AT 400 PM CDT.

$$

FORECASTER FRANKLIN