ATL: TROPICAL DEPRESSION HENRI (10L)

[wxman57]

Convection is a bit less organized this morning, and shear is definitely increasing. That rotation you see is not at the surface, most likely.

[Blown Away]

[Gustywind]

Mark Avery, Lead Meteorologist, The Weather Channel
Oct. 5, 2009 7:06 am ET
http://www.weather.com/newscenter/tropical/

There is a small area of low pressure along the southern end of a tropical wave midway between the Cape Verde Islands and the Lesser Antilles moving to the west-northwest at 15 to 20 mph. A large, though diminished, area of shower and thunderstorm activity accompanies the wave and low. Environment conditions are marginally favorable for some slow development of this system over the next few days. We will monitor the system for any strengthening.

[Gustywind]

[Gustywind]

000
AXNT20 KNHC 051044
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT MON OCT 05 2009

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST
FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED
ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1000 UTC.

...TROPICAL WAVES...

ACTIVE TROPICAL WAVE IS ALONG 44W S OF 16N MOVING W NEAR 18 KT.
SATELLITE IMAGERY AND SATELLITE DERIVED WINDS INDICATE A BROAD
AREA OF LOW/MID-LEVEL CYCLONIC FLOW IN THE VICINITY OF THE WAVE
AXIS. THE WAVE ALSO COINCIDES WITH A DEEP LAYER MOISTURE MAXIMUM
OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY. NUMEROUS STRONG
CONVECTION IS FROM 15N-18N BETWEEN 41W-46W. SCATTERED MODERATE/
STRONG CONVECTION IS FROM 11N-16N BETWEEN 46W-53W. SCATTERED
MODERATE/ISOLATED STRONG CONVECTION IS FROM 10N-14N BETWEEN
41W-46W. THIS ACTIVITY IS ALSO ENHANCED BY DIFFLUENT FLOW ALOFT.

$$
WALTON

[gatorcane]

Well it became an invest last night it appears, prior to midnight. My prediction was that it would be an invest on Sunday which did verify.

Anyway, certainly some gradual development appears likely as it heads mostly west. If shear does not get to this, certainly a player down the road with the synoptics setting up. Looks more like August or September with the steering. Even if it does not initially develop, could do so farther west.

[Gustywind]

Discussion from Crownweather: http://www.crownweather.com/?page_id=325

Discussion
I am keeping a close eye on a tropical disturbance, labeled Invest 91L. This disturbance is producing widespread, but disorganized, showers and thunderstorms and is located about 1150 miles east of the Lesser Antilles. This disturbance is under somewhat favorable environmental conditions and slow development seems likely, especially since it is so large in size as larger disturbances take longer to organize and develop. None of the global model guidance develops this system and this should be taken in account as the global models may be catching onto an environment that is not that favorable. The hurricane track models and hurricane intensity models forecast that Invest 91L will slowly intensify and may become a tropical storm over the next 2 to 3 days or so as shear values are forecast to be favorable over the next 24 hours and then become unfavorable during Tuesday and Wednesday and then become favorable again late this week. So, my thinking is that slow development seems possible over the next few days.

Again, what is interesting to me is that the global computer guidance forecasts development in the short term and then forecasts it to “poof” later this week. I’m not sure what the global models are seeing as conditions appear that they will become favorable as we head into late this week with a large area of high pressure building over and to the north of this disturbance. The fact that the global models are not developing this disturbance may be a good sign that nothing will come of Invest 91L.

If Invest 91L does develop, the steering flow suggests that it may track through the Caribbean and then turn to the north as it reaches the western Caribbean as a frontal system tracks into the Gulf of Mexico and across Florida by this weekend. This would be considered a classic October setup and I am hoping Invest 91L goes “poof” and that we don’t have to worry about it. At this time, Invest 91L does have my attention and I will be watching it closely.

The next tropical weather discussion will be issued by 6 am EDT Tuesday.

[cycloneye]

TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT MON OCT 5 2009

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

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL
STORM GRACE...LOCATED ABOUT 585 MILES NORTHEAST OF THE AZORES.

A TROPICAL WAVE LOCATED ABOUT 1000 MILES EAST OF THE WINDWARD
ISLANDS IS MOVING WEST-NORTHWESTWARD NEAR 15 MPH AND CONTINUES TO
PRODUCE A LARGE AREA OF DISORGANIZED SHOWERS AND THUNDERSTORMS.
SOME SLOW DEVELOPMENT OF THIS SYSTEM IS POSSIBLE BEFORE UPPER-LEVEL
WINDS INCREASE IN A COUPLE OF DAYS. THERE IS A LOW CHANCE...LESS
THAN 30 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING
THE NEXT 48 HOURS.

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

$$
FORECASTER BERG

[Gustywind]

000
ABNT20 KNHC 051133
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT MON OCT 5 2009

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

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL
STORM GRACE...LOCATED ABOUT 585 MILES NORTHEAST OF THE AZORES.

A TROPICAL WAVE LOCATED ABOUT 1000 MILES EAST OF THE WINDWARD
ISLANDS IS MOVING WEST-NORTHWESTWARD NEAR 15 MPH AND CONTINUES TO
PRODUCE A LARGE AREA OF DISORGANIZED SHOWERS AND THUNDERSTORMS.
SOME SLOW DEVELOPMENT OF THIS SYSTEM IS POSSIBLE BEFORE UPPER-LEVEL
WINDS INCREASE IN A COUPLE OF DAYS. THERE IS A LOW CHANCE...LESS
THAN 30 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING
THE NEXT 48 HOURS.

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

$$
FORECASTER BERG

[gatorcane]

Discussion from Crownweather: http://www.crownweather.com/?page_id=325

Discussion
I am keeping a close eye on a tropical disturbance, labeled Invest 91L. This disturbance is producing widespread, but disorganized, showers and thunderstorms and is located about 1150 miles east of the Lesser Antilles. This disturbance is under somewhat favorable environmental conditions and slow development seems likely, especially since it is so large in size as larger disturbances take longer to organize and develop. None of the global model guidance develops this system and this should be taken in account as the global models may be catching onto an environment that is not that favorable. The hurricane track models and hurricane intensity models forecast that Invest 91L will slowly intensify and may become a tropical storm over the next 2 to 3 days or so as shear values are forecast to be favorable over the next 24 hours and then become unfavorable during Tuesday and Wednesday and then become favorable again late this week. So, my thinking is that slow development seems possible over the next few days.

Again, what is interesting to me is that the global computer guidance forecasts development in the short term and then forecasts it to “poof” later this week. I’m not sure what the global models are seeing as conditions appear that they will become favorable as we head into late this week with a large area of high pressure building over and to the north of this disturbance. The fact that the global models are not developing this disturbance may be a good sign that nothing will come of Invest 91L.

If Invest 91L does develop, the steering flow suggests that it may track through the Caribbean and then turn to the north as it reaches the western Caribbean as a frontal system tracks into the Gulf of Mexico and across Florida by this weekend. This would be considered a classic October setup and I am hoping Invest 91L goes “poof” and that we don’t have to worry about it. At this time, Invest 91L does have my attention and I will be watching it closely.

The next tropical weather discussion will be issued by 6 am EDT Tuesday.

Interesting here is what I said last night. That last paragraph looks familiar.....what is crownweather?

Looking at the long-range H5 charts suggest that if it develops, it could head through the Caribbean and maybe make a NW turn then N because there is quite a cold front that is expected to head towards the GOM and FL by next weekend. That would be a classic October setup should that unfold. Hopefully it goes poof and we don't have to worry about it but certainly it has my attention at the moment given the time of year we are in

[Gustywind]

Invest #91 http://tropics.hamweather.com/2009/atla ... est91.html

Tropical Disturbance Summary
Invest #91
Location: Central Atlantic Lat: 11.4N Lon: 44.4W Moving: W 17 mph (15 kts) Pressure: 29.8 in (1009 mb)

Invest #91 Track History
Date Position Moving Speed Pressure Winds
(UTC) Lat Lon mph (kts) in (mb) mph (kts)
0600 MON OCT 05 11.4N 44.4W W 17 (15) 29.8 (1009) 29 (25)
0000 MON OCT 05 11.2N 42.9W W 18 (16) 29.8 (1009) 29 (25)

[boca]

91L looks less organized this morning.If this does develop I'll be shocked.Like people were saying its 2009.Its getting elongated on sat, which usually means shear.

[Evil Jeremy]

No GFDL runs yet, and the only model other than the 00z BAM (outdated, shouldnt the 12z run by up by now?) run is the 06z NOGAPS. Why are the models not running?

[cycloneye]

91L looks less organized this morning.If this does develop I'll be shocked.Like people were saying its 2009.Its getting elongated on sat, which usually means shear.

But if it stays like this without developing,we will get plenty of rain from it in the NE Caribbean.

[cycloneye]

12 UTC Best Track

AL, 91, 2009100512, , BEST, 0, 117N, 456W, 25, 1009, DB

ftp://ftp.tpc.ncep.noaa.gov/atcf/tcweb/ ... 009.invest

[cycloneye]

The 06z run just came out but I asume the 12z one will be out shortly.

WHXX01 KWBC 051203
CHGHUR
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1203 UTC MON OCT 5 2009

DISCLAIMER...NUMERICAL MODELS ARE SUBJECT TO LARGE ERRORS.
PLEASE REFER TO NHC OFFICIAL FORECASTS FOR TROPICAL CYCLONE
AND SUBTROPICAL CYCLONE INFORMATION.

ATLANTIC OBJECTIVE AIDS FOR

DISTURBANCE INVEST (AL912009) 20091005 0600 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
091005 0600 091005 1800 091006 0600 091006 1800

LAT LON LAT LON LAT LON LAT LON
BAMS 11.4N 44.4W 13.0N 47.4W 14.7N 50.6W 16.4N 53.8W
BAMD 11.4N 44.4W 12.7N 47.1W 14.1N 49.6W 15.6N 52.0W
BAMM 11.4N 44.4W 12.6N 47.3W 13.9N 50.2W 15.3N 53.0W
LBAR 11.4N 44.4W 12.3N 47.3W 13.6N 50.3W 15.0N 53.3W
SHIP 25KTS 28KTS 32KTS 38KTS
DSHP 25KTS 28KTS 32KTS 38KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
091007 0600 091008 0600 091009 0600 091010 0600

LAT LON LAT LON LAT LON LAT LON
BAMS 17.9N 56.5W 19.6N 60.6W 19.5N 64.0W 17.7N 68.4W
BAMD 17.1N 54.0W 19.7N 56.8W 20.4N 59.2W 18.6N 63.2W
BAMM 16.5N 55.3W 17.6N 59.2W 17.4N 63.4W 15.7N 68.9W
LBAR 16.9N 56.0W 20.3N 58.9W 23.0N 57.5W 21.0N 52.2W
SHIP 45KTS 51KTS 56KTS 66KTS
DSHP 45KTS 51KTS 56KTS 66KTS

...INITIAL CONDITIONS...
LATCUR = 11.4N LONCUR = 44.4W DIRCUR = 280DEG SPDCUR = 16KT
LATM12 = 10.9N LONM12 = 41.3W DIRM12 = 281DEG SPDM12 = 16KT
LATM24 = 10.4N LONM24 = 38.2W
WNDCUR = 25KT RMAXWD = 30NM WNDM12 = 25KT
CENPRS = 1009MB OUTPRS = 1011MB OUTRAD = 175NM SDEPTH = M
RD34NE = 0NM RD34SE = 0NM RD34SW = 0NM RD34NW = 0NM

[cycloneye]

12:00 UTC Bam Models

446
WHXX01 KWBC 051228
CHGHUR
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1228 UTC MON OCT 5 2009

DISCLAIMER...NUMERICAL MODELS ARE SUBJECT TO LARGE ERRORS.
PLEASE REFER TO NHC OFFICIAL FORECASTS FOR TROPICAL CYCLONE
AND SUBTROPICAL CYCLONE INFORMATION.

ATLANTIC OBJECTIVE AIDS FOR

DISTURBANCE INVEST (AL912009) 20091005 1200 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
091005 1200 091006 0000 091006 1200 091007 0000

LAT LON LAT LON LAT LON LAT LON
BAMS 11.7N 45.6W 13.1N 48.5W 14.5N 51.7W 15.9N 54.6W
BAMD 11.7N 45.6W 12.8N 48.2W 14.0N 50.9W 15.2N 53.3W
BAMM 11.7N 45.6W 12.8N 48.4W 13.9N 51.2W 15.0N 53.9W
LBAR 11.7N 45.6W 12.8N 48.3W 14.2N 51.2W 15.7N 53.9W
SHIP 25KTS 25KTS 28KTS 35KTS
DSHP 25KTS 25KTS 28KTS 35KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
091007 1200 091008 1200 091009 1200 091010 1200

LAT LON LAT LON LAT LON LAT LON
BAMS 17.0N 57.2W 18.2N 61.1W 17.9N 64.5W 16.8N 68.3W
BAMD 16.3N 55.5W 18.2N 59.3W 18.1N 62.8W 16.2N 68.3W
BAMM 15.8N 56.1W 16.7N 60.1W 16.3N 64.0W 14.8N 69.3W
LBAR 17.3N 56.4W 20.5N 58.9W 22.3N 57.0W 21.0N 52.5W
SHIP 41KTS 48KTS 56KTS 69KTS
DSHP 41KTS 48KTS 56KTS 69KTS

...INITIAL CONDITIONS...
LATCUR = 11.7N LONCUR = 45.6W DIRCUR = 280DEG SPDCUR = 14KT
LATM12 = 11.2N LONM12 = 42.9W DIRM12 = 280DEG SPDM12 = 14KT
LATM24 = 10.6N LONM24 = 39.6W
WNDCUR = 25KT RMAXWD = 30NM WNDM12 = 25KT
CENPRS = 1009MB OUTPRS = 1011MB OUTRAD = 175NM SDEPTH = M
RD34NE = 0NM RD34SE = 0NM RD34SW = 0NM RD34NW = 0NM

[HURAKAN]

Some vorticity

[CrazyC83]

And we thought the season was over? There seems to be a decent chance that we could get Henri out of this...it seems that storms are forming wherever they can this year...

[fci]

Discussion from Crownweather: http://www.crownweather.com/?page_id=325

Discussion
I am keeping a close eye on a tropical disturbance, labeled Invest 91L. This disturbance is producing widespread, but disorganized, showers and thunderstorms and is located about 1150 miles east of the Lesser Antilles. This disturbance is under somewhat favorable environmental conditions and slow development seems likely, especially since it is so large in size as larger disturbances take longer to organize and develop. None of the global model guidance develops this system and this should be taken in account as the global models may be catching onto an environment that is not that favorable. The hurricane track models and hurricane intensity models forecast that Invest 91L will slowly intensify and may become a tropical storm over the next 2 to 3 days or so as shear values are forecast to be favorable over the next 24 hours and then become unfavorable during Tuesday and Wednesday and then become favorable again late this week. So, my thinking is that slow development seems possible over the next few days.

Again, what is interesting to me is that the global computer guidance forecasts development in the short term and then forecasts it to “poof” later this week. I’m not sure what the global models are seeing as conditions appear that they will become favorable as we head into late this week with a large area of high pressure building over and to the north of this disturbance. The fact that the global models are not developing this disturbance may be a good sign that nothing will come of Invest 91L.

If Invest 91L does develop, the steering flow suggests that it may track through the Caribbean and then turn to the north as it reaches the western Caribbean as a frontal system tracks into the Gulf of Mexico and across Florida by this weekend. This would be considered a classic October setup and I am hoping Invest 91L goes “poof” and that we don’t have to worry about it. At this time, Invest 91L does have my attention and I will be watching it closely.

The next tropical weather discussion will be issued by 6 am EDT Tuesday.

Interesting here is what I said last night. That last paragraph looks familiar.....what is crownweather?

Looking at the long-range H5 charts suggest that if it develops, it could head through the Caribbean and maybe make a NW turn then N because there is quite a cold front that is expected to head towards the GOM and FL by next weekend. That would be a classic October setup should that unfold. Hopefully it goes poof and we don't have to worry about it but certainly it has my attention at the moment given the time of year we are in

Imitation is the highest form of flattery!!!!!