Gulf Of Mexico Tropical Development 2011, Until Invest Formation ONLY - Fronts, Waves, LPs Options

[jdrenken]

The Euro has a gulf system, while the GFS has a system in the Bahamas.

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
421 AM EDT TUE OCT 04 2011

VALID 12Z SAT OCT 08 2011 - 12Z TUE OCT 11 2011

...WET/WINDY WEATHER POSSIBLE ACROSS FLORIDA/GEORGIA THIS WEEKEND
INTO EARLY NEXT WEEK...

THE EVOLUTION OF A HYBRID/SUBTROPICAL CYCLONE NEAR FLORIDA REMAINS
SIMILAR TO WHAT WAS EXPECTED THIS TIME YESTERDAY...AS THE 12Z
GLOBAL ENSEMBLE GUIDANCE HAS KEPT GOOD DAY TO DAY CONTINUITY WITH
THE SYSTEM AND STILL SHOWS GOOD SUPPORT FOR ITS EXISTENCE. THIS
LOW IS SPAWNED BY ENERGY FROM THE WESTERLIES WHICH DROPS
SOUTH/SOUTHWEST INTO THE FLORIDA PENINSULA IN A FEW DAYS. A
MOBILE RIDGE TO ITS NORTH AND WEAKNESS TO THE CYCLONES NORTHWEST
CAUSED BY THE PLAINS TROUGH SHOULD LEAD TO A SLOW NORTHWEST
PROGRESSION OF THIS LOW WITH TIME. THE ECMWF/CANADIAN
DETERMINISTIC RUNS HAVE BECOME MORE EMPHATIC WITH ITS DEEPENING
SINCE THIS TIME YESTERDAY...LIKELY DUE TO THE TEPID SEA SURFACE
TEMPERATURES ACROSS THE FLORIDA STRAITS...BUT THEY LIE ON THE WEST
SIDE OF THE 12Z GLOBAL ENSEMBLE SPREAD. GALE-FORCE WINDS AND
ASSOCIATED HEAVY RAINFALL REMAIN IN THE CARDS ACROSS NORTHEAST
FLORIDA/GEORGIA FROM SATURDAY ONWARD. POSSIBLE OCTOBER ANALOGS TO
THIS FEATURE /WHICH SHOWED A SIMILAR PATTERN ACROSS THE WEST AND
HIGH PLAINS/ REMAIN THE OCTOBER 14 1956 QUASI-TROPICAL CYCLONE AND
THE OCTOBER 4 1974 CYCLONE /SUBTROPICAL STORM FOUR/. THE TRACK OF
THIS SYSTEM IS EXPECTED TO LIE NORTHEAST/TO THE RIGHT OF THE MAY
19-20 2009 GULF GALE WHICH CAUSED A LARGE AREA OF OVER SEVEN
INCHES OF RAIN ACROSS NORTHEAST FLORIDA. STAY TUNED.

ROTH

[MAC292OH10]

after 3 weeks of on again off again by the GFS, we may have a little something to work with....

Global Tropical Hazards Outlook Discussion
Last Updated: 10.04.11 Valid: 10.05.11 - 10.18.11

The MJO remained active during the past week with the enhanced convective phase shifting from the Maritime continent to the western Pacific and its focus is primarily north of the equator. Atmospheric Kelvin wave (KW) activity continues to be superimposed on the slower ongoing MJO variability and an equatorial Rossby wave (ERW) has contributed to maintaining enhanced convection across Southeast Asia. The Asian monsoon circulation was much weaker than in previous weeks. Enhanced convection was observed from Southeast Asia across the western Pacific and also across much of west-central Africa. Drier-than-average conditions were observed over India, the western Maritime continent and various areas across the tropical western hemisphere. Super typhoon Nalgae impacted the Philippines with dangerous winds and heavy rainfall during the past week.

The WH MJO index showed continued eastward propagation during the past week, but this movement has slowed in recent days most likely because it is being impacted by westward moving convective activity in the far western Pacific and Southeast Asia. The observed evolution of the MJO index was somewhat well forecast from both one and two weeks ago,although the amplitude of the index as forecast by the models was too weak and in some instances too fast.

The MJO is forecast to remain active with MJO index model forecasts indicating continued eastward propagation of the enhanced convective phase from the western Pacific to the western hemisphere (WH phase 6 to 8) over the next two weeks. There is very good model agreement in this forecast. At the current time, the amplitude of the MJO index forecasts favors at least moderate strength MJO activity.

For Week-1, enhanced convection is forecast from the South China Sea into the western Pacific and suppressed convection is favored from India across the eastern Indian Ocean to Indonesia primarily associated with the MJO. tropical cyclone Nalgae is expected to result in heavy rainfall very early in the period across parts of southeast Asia. Tropical cyclone development remains a threat east of the Philippines as the enhanced phase of the MJO exits this region. The MJO favors tropical development in the eastern Pacific and enhanced rainfall across portions of Central America and northern South America during this period.A frontal boundary and general low pressure favors enhanced rainfall for the Bahamas and parts of the Caribbean islands and Florida and increases the threat for tropical devlopment north of Cuba in close proximity to Florida during Week-1. Model forecast guidance continues to favor above-average rainfall for areas in west central Africa.

The area of suppressed convection in the eastern hemisphere is forecast to shift eastward and encompass the Maritime continent and begin to impact the western Pacific. Later during Week-2, there is some potential for convection to increase across east central Africa and the western Indian Ocean ahead of the next enhanced convective phase of the MJO. During Week-2, the MJO signal continues the threat for tropical cyclone development in the eastern Pacific and enhanced rainfall in the Americas as well as increases the chances of tropical cyclone development in the western Caribbean Sea.

For local U.S. interests, the forecast MJO phase would favor continued potential for above-average precipitation for the Northwest quarter of the U.S. during much of the period including parts of California. The MJO also increases the threat for tropical cyclogenesis in the western Caribbean Sea during Week-2 and if development occurs the Southeast U.S. should monitor for a potential track to the north and east.

[jdrenken]

Larry Cosgrove's thoughts. He states that the system will form around the Strait of Yucatan and move towards FL.

[jdrenken]

The latest 0Z suites...

Non-Euro


Euro hasn't updated yet on this server, but it's a gulf system like the others.

Source

[jdrenken]

12Z Euro being stubborn...

[jdrenken]

HPC's Day 3-7

500mb


Surface

[Superstorm93]

Sub-tropical storm gets a "meh"

ECMWF

[Superstorm93]

If conditions were more favorable, we could have been seen something more interesting than a STC in the Caribbean.

[WEATHERFREAK]

According to the HPC, it should make land fall on Tuesday morning around the big bend area.

[jdrenken]

OPC's thoughts...

96hr issued 06OCT11

Surface


500mb

[jdrenken]

Frank's thoughts

[jdrenken]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT SAT OCT 8 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL
STORM PHILIPPE...LOCATED ABOUT 1215 MILES WEST OF THE AZORES.

1. A SURFACE TROUGH LOCATED FROM THE EXTREME NORTHWESTERN CARIBBEAN SEA
ACROSS CENTRAL CUBA AND INTO THE CENTRAL BAHAMAS IS PRODUCING
WIDESPREAD CLOUDINESS AND THUNDERSTORMS OVER MUCH OF CENTRAL AND
EASTERN CUBA...MOST OF THE FLORIDA PENINSULA AND THE FLORIDA
KEYS...ALL OF THE BAHAMAS...AND ADJACENT ATLANTIC WATERS. THE
TROUGH HAS BECOME A LITTLE BETTER DEFINED AND SURFACE PRESSURES ARE
SLOWLY FALLING. GRADUAL DEVELOPMENT OF THIS LARGE AREA OF DISTURBED
WEATHER IS POSSIBLE OVER THE NEXT FEW DAYS AS IT MOVES WESTWARD OR
NORTHWESTWARD AT 5 TO 10 MPH. THIS SYSTEM HAS A MEDIUM CHANCE...
30 PERCENT...OF BECOMING A TROPICAL OR SUBTROPICAL CYCLONE DURING
THE NEXT 48 HOURS. REGARDLESS OF DEVELOPMENT...THIS DISTURBANCE
WILL PRODUCE STRONG GUSTY WINDS AND LOCALLY HEAVY RAINFALL ACROSS
PORTIONS OF THE BAHAMAS AND THE FLORIDA PENINSULA OVER THE NEXT
COUPLE OF DAYS. ADDITIONAL INFORMATION ON THIS DEVELOPING GALE AREA
CAN BE FOUND IN HIGH SEAS FORECASTS ISSUED BY THE NATIONAL WEATHER
SERVICE...UNDER AWIPS HEADER NFDHSFAT1 AND WMO HEADER FZNT01 KWBC.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER STEWART

[jdrenken]

Wave is from Honduras to Cuba

[idecline]

Wave is from Honduras to Cuba

Haven't been here for 4 days but that low off the Yucatan seems to be getting very well ventilated...very quickly...I was only looking at the GOM water vapor loop but there seems to be persistent convection offshore with a central area of heavy dense cloudmass and the beginnings of atmospheric spin ...IMO.. if I am not mistaken..I am looking at this trough becoming more organized as the night wears on...

Just guessing that an invest will be coming very soon with TC development possible in the next few days... that conditions are ripe for a quickly developing storm with the low shear and very warm SST's.

[east coast storm]

Haven't been here for 4 days but that low off the Yucatan seems to be getting very well ventilated...very quickly...I was only looking at the GOM water vapor loop but there seems to be persistent convection offshore with a central area of heavy dense cloudmass and the beginnings of atmospheric spin ...IMO.. if I am not mistaken..I am looking at this trough becoming more organized as the night wears on...

Just guessing that an invest will be coming very soon with TC development possible in the next few days... that conditions are ripe for a quickly developing storm with the low shear and very warm SST's.

NHC has it up to 50%