Invest 99L E of Lesser Antilles,Comments,Sat Pics,Etc #3

[cheezyWXguy]

thats 950 mb...how close to the ground is that?

[curtadams]

Remember - the GFDL had Alberto strengthening to a Cat 3. Repeatedly. Sometimes over land! It can be psychotically bullish.

[LAwxrgal]

I haven't followed the tropics too closely this year cause of other obligations, but this thing is no more than an open wave right now, right?

[kenl01]

Next people are gonna be screaming that this could be a cat 5 hitting the US when there's nothing out there.........

That's something we're going to hear the rest of the season for every blob of thunderstorms..........

I'm expecting that........oh well.

[P.K.]

thats 950 mb...how close to the ground is that?

Based on the 1200 GMT soundings in the area it is currently just below 600m. It does depend on the pressure at the surface though as in tropical cyclones the pressure can be less than 950hPa so this height can be negative.

[Recurve]

I haven't followed the tropics too closely this year cause of other obligations, but this thing is no more than an open wave right now, right?

LAwxgal -- that's right.

Latest discussion:

...TROPICAL WAVES...

A CARIBBEAN SEA TROPICAL WAVE IS ALONG 72W/73W SOUTH OF 20N
MOVING WEST 20 KT. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS
HAVE SHIFTED AND NOW COVER THE BRITISH VIRGIN ISLANDS AND THE
U.S. VIRGIN ISLANDS FROM 17N TO 20N BETWEEN 64W AND 67W.
LINGERING PRECIPITATION OVER PUERTO RICO STILL IS POSSIBLE. ALL
THE COLDEST CLOUD TOP TEMPERATURES NOW ARE OVER THE WATERS TO
THE EAST AND NORTH OF PUERTO RICO. SHOWER AND THUNDERSTORM
ACTIVITY ASSOCIATED WITH A TROPICAL WAVE HAS BECOME A LITTLE
BETTER ORGANIZED THIS MORNING. SOME SLOW DEVELOPMENT OF THE
SYSTEM IS POSSIBLE DURING THE NEXT FEW DAYS. LOCALLY HEAVY
RAINFALL CAN BE EXPECTED TODAY IN PARTS OF PUERTO RICO...THE
VIRGIN ISLANDS...AND EASTERN HISPANIOLA. WIDELY SCATTERED
MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS EXIST ALSO
FROM 13N TO 15N BETWEEN 63W AND 66W.

[Ola]

I haven't followed the tropics too closely this year cause of other obligations, but this thing is no more than an open wave right now, right?

LAwxgal -- that's right.

Latest discussion:

...TROPICAL WAVES...

A CARIBBEAN SEA TROPICAL WAVE IS ALONG 72W/73W SOUTH OF 20N
MOVING WEST 20 KT. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS
HAVE SHIFTED AND NOW COVER THE BRITISH VIRGIN ISLANDS AND THE
U.S. VIRGIN ISLANDS FROM 17N TO 20N BETWEEN 64W AND 67W.
LINGERING PRECIPITATION OVER PUERTO RICO STILL IS POSSIBLE. ALL
THE COLDEST CLOUD TOP TEMPERATURES NOW ARE OVER THE WATERS TO
THE EAST AND NORTH OF PUERTO RICO. SHOWER AND THUNDERSTORM
ACTIVITY ASSOCIATED WITH A TROPICAL WAVE HAS BECOME A LITTLE
BETTER ORGANIZED THIS MORNING. SOME SLOW DEVELOPMENT OF THE
SYSTEM IS POSSIBLE DURING THE NEXT FEW DAYS. LOCALLY HEAVY
RAINFALL CAN BE EXPECTED TODAY IN PARTS OF PUERTO RICO...THE
VIRGIN ISLANDS...AND EASTERN HISPANIOLA. WIDELY SCATTERED
MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS EXIST ALSO
FROM 13N TO 15N BETWEEN 63W AND 66W.

You have the wrong wave.

[Extremeweatherguy]

I haven't followed the tropics too closely this year cause of other obligations, but this thing is no more than an open wave right now, right?

LAwxgal -- that's right.

Latest discussion:

...TROPICAL WAVES...

A CARIBBEAN SEA TROPICAL WAVE IS ALONG 72W/73W SOUTH OF 20N
MOVING WEST 20 KT. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS
HAVE SHIFTED AND NOW COVER THE BRITISH VIRGIN ISLANDS AND THE
U.S. VIRGIN ISLANDS FROM 17N TO 20N BETWEEN 64W AND 67W.
LINGERING PRECIPITATION OVER PUERTO RICO STILL IS POSSIBLE. ALL
THE COLDEST CLOUD TOP TEMPERATURES NOW ARE OVER THE WATERS TO
THE EAST AND NORTH OF PUERTO RICO. SHOWER AND THUNDERSTORM
ACTIVITY ASSOCIATED WITH A TROPICAL WAVE HAS BECOME A LITTLE
BETTER ORGANIZED THIS MORNING. SOME SLOW DEVELOPMENT OF THE
SYSTEM IS POSSIBLE DURING THE NEXT FEW DAYS. LOCALLY HEAVY
RAINFALL CAN BE EXPECTED TODAY IN PARTS OF PUERTO RICO...THE
VIRGIN ISLANDS...AND EASTERN HISPANIOLA. WIDELY SCATTERED
MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS EXIST ALSO
FROM 13N TO 15N BETWEEN 63W AND 66W.

You have the wrong wave.

yeah, that is the other wave over in the Caribbean. Plus, this is also from the 8:05am discussion. A new discussion should be out soon.

[Recurve]

You have the wrong wave.

here you go

...SPECIAL FEATURE...

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 15N48W 11N50W 5N52W
MOVING WEST 20 KT. A 1012 MB LOW PRESSURE CENTER IS ALONG THE
WAVE NEAR 11N50W. THIS SYSTEM STILL HAS THE POTENTIAL TO BECOME
A TROPICAL DEPRESSION DURING THE NEXT FEW DAYS ALTHOUGH
CONDITIONS ARE CURRENTLY ONLY MARGINALLY FAVORABLE FOR
DEVELOPMENT. WIDELY SCATTERED MODERATE SHOWERS TO ISOLATED
STRONG THUNDERSTORMS ARE WITHIN 30 NM ON EITHER SIDE OF
5N47W 11N47W...AND FROM 10N TO 14N BETWEEN 47W AND 56W.

[Extremeweatherguy]

here is the 72 hr. surface forecast. Notice the wording "possible tropical cyclone", this is interesting because this wording was never there before.

http://www.nhc.noaa.gov/tafb_latest/atl ... BW_sm3.gif

[Extremeweatherguy]

You have the wrong wave.

here you go

...SPECIAL FEATURE...

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 15N48W 11N50W 5N52W
MOVING WEST 20 KT. A 1012 MB LOW PRESSURE CENTER IS ALONG THE
WAVE NEAR 11N50W. THIS SYSTEM STILL HAS THE POTENTIAL TO BECOME
A TROPICAL DEPRESSION DURING THE NEXT FEW DAYS ALTHOUGH
CONDITIONS ARE CURRENTLY ONLY MARGINALLY FAVORABLE FOR
DEVELOPMENT. WIDELY SCATTERED MODERATE SHOWERS TO ISOLATED
STRONG THUNDERSTORMS ARE WITHIN 30 NM ON EITHER SIDE OF
5N47W 11N47W...AND FROM 10N TO 14N BETWEEN 47W AND 56W.

There is also a low pressure area along the wave. It is the low pressure area that the NHC is interested in.

[ammmyjjjj]

Next people are gonna be screaming that this could be a cat 5 hitting the US when there's nothing out there.........

That's something we're going to hear the rest of the season for every blob of thunderstorms..........

I'm expecting that........oh well.

I think it's only natural for people to be excited, and want to be prepared, about this stuff. It's why we are all here, right?

[kenl01]

New comment just out about 99L, for whatever it's worth, from Jeff Masters Blog:


Wind shear has increased to 25knots around 99L. 99L has done well in the battle against dust, and water vapor imagery shows that dry air is having little effects on 99L....

http://cimss.ssec.wisc.edu/tropic/real- ... wg8wxc.GIF

http://www.ssd.noaa.gov/goes/flt/t1/wv-l.jpg


All that being said, chances of 99L to become a TD are decreasing, because of wind shear- 15%.

Any thoughts about that statement ?

[Scorpion]

Where is this shear coming from?

[Recurve]

for those who need it, here's the NRL site where they identify investigation areas:

http://www.nrlmry.navy.mil/tc_pages/tc_home.html

[Scorpion]

I don't see 25 kts around 99L. Not even close. Looks more like 10.

[Extremeweatherguy]

New comment just out about 99L, for whatever it's worth, from Jeff Masters Blog:


Wind shear has increased to 25knots around 99L. 99L has done well in the battle against dust, and water vapor imagery shows that dry air is having little effects on 99L....

http://cimss.ssec.wisc.edu/tropic/real- ... wg8wxc.GIF

http://www.ssd.noaa.gov/goes/flt/t1/wv-l.jpg


All that being said, chances of 99L to become a TD are decreasing, because of wind shear- 15%.

Any thoughts about that statement ?

wait a second? Jeff Masters says that 99L is doing very well against all the dry air and dust, yet this now has a lesser chance of becoming a TD? I don't think so...

BTW: Next time post a link to Jeff Master's blog when mentioning him.

[Recurve]

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT SUN JUL 30 2006

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...SPECIAL FEATURE...

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 50W/51W SOUTH OF 15N. A
1012 MB LOW PRESSURE CENTER IS ALONG THE WAVE NEAR 11N51W.
WIDELY SCATTERED MODERATE CONVECTION IS ASSOCIATED WITH THE
LOW/WAVE. ALTHOUGH CONDITIONS ARE CURRENTLY ONLY MARGINALLY
FAVORABLE FOR DEVELOPMENT...THIS SYSTEM STILL HAS THE POTENTIAL
TO BECOME A TROPICAL DEPRESSION OVER THE NEXT COUPLE OF DAYS AS
IT MOVES WEST-NORTHWESTWARD AT 15 TO 20 MPH.
...TROPICAL WAVES...

A SECOND TROPICAL WAVE IS ALONG 75W SOUTH OF 21N MOVING WEST
AROUND 20 KT. CLUSTERS OF MODERATE/ISOLATED STRONG CONVECTION
ARE ON EITHER SIDE OF THE WAVE AXIS FROM 15N-18N BETWEEN
71W-80W. THE WAVE IS MOVING AWAY FROM PUERTO RICO AND THE VIRGIN
ISLANDS... BUT AN AREA OF MODERATE SHOWERS WITH EMBEDDED TSTMS
REMAINS OVER THE NORTHEASTERN CARIBBEAN SEA...HISPANIOLA...
PUERTO RICO...AND THE VIRGIN ISLANDS. THIS CONVECTIVE ACTIVITY
IS NOW ASSOCIATED WITH A SURFACE TROUGH THAT CROSSES THE
ENCHANTED ISLAND. EARLIER THIS MORNING...SAN JUAN REPORTED 2.78
INCHES OF RAIN. THIS SYSTEM HAS BECOME A LITTLE BETTER ORGANIZED
THIS MORNING AND SOME SLOW DEVELOPMENT IS POSSIBLE OVER THE NEXT
COUPLE OF DAYS AS IT MOVES WEST-NORTHWESTWARD AT 10 TO 15 MPH.

THE THIRD TROPICAL WAVE IS INLAND OVER THE YUCATAN PENINSULA AND
GUATEMALA ALONG 90W SOUTH OF 20N MOVING WEST 20 KT. MOST OF THE
CONVECTIVE ACTIVITY RELATED TO THE WAVE IS ON THE PACIFIC SIDE.
THIS TROPICAL WAVE WILL MOVE THROUGH THE BAY OF CAMPECHE THIS
AFTERNOON AND TONIGHT.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 9N14W 8N30W 13N45W 9N52W 8N60W. A
CLUSTER OF MODERATE/ISOLATED STRONG CONVECTION HAS MOVED OFF THE
WEST COAST OF AFRICA PROBABLY ASSOCIATED WITH A TROPICAL WAVE.
SHOWERS AND THUNDERSTORMS EXIST FROM 6N-12N BETWEEN 16W-20W.
SCATTERED MODERATE CONVECTION IS WITHIN 40/60 NM ON EITHER SIDE
OF THE ITCZ AXIS FROM 24W-30W AND FROM 38W-45W.

...DISCUSSION...
THE GULF OF MEXICO...
AN UPPER RIDGE EXTENDS ALONG THE NORTHERN GULF WATERS AND THE
SOUTHEASTERN U.S.. TWO UPPER LEVEL LOW CENTERS REMAINS OVER THE
AREA...ONE IS OVER THE N-CENTRAL GULF WHILE THE SECOND ONE HAS
MOVED INLAND OVER NE MEXICO. AN UPPER LEVEL HIGH IS OVER THE BAY
OF CAMPECHE COVERING SOUTH MEXICO...THE NW CARIBBEAN AND
NORTHERN CENTRAL AMERICA. SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS DOT THE NORTHERN HALF OF THE GULF. SCATTERED
SHOWERS ARE ALSO SEEN OVER THE BAY OF CAMPECHE. MODERATE
SUBSIDENCE DOMINATES THE SE GULF. A 1018 MB SURFACE HIGH IS OVER
THE SE U.S. WITH A RIDGE EXTENDING WWD TO EASTERN TEXAS. BROAD
10-15 SELY FLOW DOMINATES THE GULF OF MEXICO. A RIDGE WILL
PERSIST ACROSS THE NORTHERN GULF DURING THE NEXT FEW DAYS.

THE CARIBBEAN SEA...
THE MAIN FEATURE ACROSS THE BASIN IS THE AREA OF SHOWERS AND
TSTMS OVER THE NORTHEASTERN CARIBBEAN SEA...HISPANIOLA...PUERTO
RICO...AND THE VIRGIN ISLANDS ASSOCIATED WITH A SURFACE TROUGH.
SEE TROPICAL WAVES SECTION. A RIDGE EXTENDS ACROSS THE NW
CARIBBEAN AND NORTHERN CENTRAL AMERICA FROM AN UPPER LEVEL HIGH
LOCATED OVER THE BAY OF CAMPECHE. ANOTHER UPPER LEVEL HIGH IS
OVER THE LEEWARD ISLANDS...ENHANCING THE DEVELOPMENT OF THE
CONVECTIVE ACTIVITY RELATED TO THE ABOVE MENTIONED SURFACE
TROUGH. THIS RIDGE HAS BECOME THE DOMINATING FEATURE ACROSS THE
E/CENTRAL CARIBBEAN AND NORTHERN SOUTH AMERICA. AN UPPER TROUGH
RUNS FROM A CUT-OFF LOW LOCATED NORTH OF THE BAHAMAS ACROSS CUBA
AND THE CAYMAN ISLANDS TO A SECOND UPPER CYCLONE CENTERED OVER
THE NW CARIBBEAN. ABUNDANT UPPER LEVEL MOISTURE COVERS MUCH OF
THE CARIBBEAN SEA. MODERATE TO STRONG SUBSIDENCE COVERS CUBA AND
THE CENTRAL BAHAMAS. 10-20 KT TRADE WINDS BLOW ACROSS THE AREA.

THE ATLANTIC OCEAN...
A SURFACE RIDGE GOES FROM 1021 MB HIGH PRESSURE CENTER LOCATED
NEAR 27N-60W TO NORTH FLORIDA AND THE SE U.S. WHERE THERE IS A
SECONDARY CENTER WITH A CENTRAL PRESSURE VALUE OF 1018 MB.
SCATTERED PATCHES OF LOW LEVEL CLOUDS ARE FROM 20N-30N EAST OF
60 W. WIDELY SCATTERED SHOWERS ARE OVER THE E ATLC N OF 26N WEST
OF 75W. IN THE UPPER LEVELS...MIDDLE/UPPER LEVEL LOW CENTER IS
JUST NORTH OF THE BAHAMAS NEAR 25N74W. A HIGH IS OVER THE
LEEWARD ISLANDS NEAR 18N63W. AN UPPER RIDGE EXTENDS OVER THE
E/CENTRAL ATLC FROM A HIGH ANCHORED OVER THE WEST COAST OF
AFRICA NEAR 17N16W. THE RIDGE AXIS IS ALONG 19/20N. MODERATE TO
STRONG SUBSIDENCE IS FOUND OVER THE ATLC FROM 20N-30N EAST OF
50W.

$$
GR

[Derek Ortt]

the shear is coming from the large upper trough.

This is not a really good candidate for development. Patience pays, as we will soon be in the heart of the hurricane season

[Thunder44]

I don't see 25 kts around 99L. Not even close. Looks more like 10.

QS pass this morning showed a small area of 30kt - 35kt winds. Just one lonely barb though so it may not be truely representive of the entire system. No closed surface circulation either.

http://manati.orbit.nesdis.noaa.gov/sto ... _at_0.html