[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 251742
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT THU JUN 25 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...TROPICAL WAVES...

A TROPICAL WAVE EXTENDS FROM 13N31W TO 9N32W TO 4N33W MOVING W
NEAR 15 KT. THIS WAVE IS ASSOCIATED WITH A RELATIVELY LOW
AMPLITUDE MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL
PRECIPITABLE WATER PRODUCT FROM CIMSS. THIS WAVE IS ALSO
ASSOCIATED WITH LOW LEVEL CYCLONIC CIRCULATION BASED ON THE
CIMSS WAVETRAK PRODUCT. SCATTERED MODERATE CONVECTION IS FROM
6N-9N BETWEEN 31W-33W.

A TROPICAL WAVE IS ALONG 59W/60W S OF 19N MOVING W NEAR 20 KT.
THIS WAVE IS ALSO ASSOCIATED WITH A MAXIMUM IN DEEP LAYER
MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM
CIMSS. VISIBLE SATELLITE IMAGERY INDICATES THAT THIS WAVE
COINCIDES WITH AN INVERTED-V PATTERN IN THE COVERAGE OF LOW
LEVEL CLOUDS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS
FROM 10N-12N BETWEEN 54W-59W. ALSO...SCATTERED LOW-TOPPED
SHOWERS ASSOCIATED WITH THIS WAVE ARE AFFECTING PORTIONS OF THE
WINDWARD ISLANDS.

A TROPICAL WAVE EXTENDS FROM 21N73W TO 15N75W TO 9N75W MOVING W
NEAR 15 KT. THIS WAVE IS ASSOCIATED WITH A WELL-DEFINED MAXIMUM
IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER
PRODUCT FROM CIMSS. THIS WAVE IS ALSO ASSOCIATED WITH LOW LEVEL
CYCLONIC CIRCULATION BASED ON THE CIMSS WAVETRAK PRODUCT. STABLE
ATMOSPHERIC CONDITIONS BENEATH A BROAD UPPER LEVEL RIDGE OVER
THE CENTRAL AND E CARIBBEAN IS INHIBITING DEEP CONVECTION NEAR
THIS WAVE. HOWEVER...SCATTERED SHOWERS ARE OCCURRING FROM
15N-19N BETWEEN 71W-78W INCLUDING PORTIONS OF HISPANIOLA AND
JAMAICA.

...THE ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 9N13W 8N25W 6N39W 6N48W 7N59W.
SCATTERED MODERATE TO STRONG CONVECTION IS FROM 5N-11N BETWEEN
14W-22W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM
6N-8N BETWEEN 24W-29W. SCATTERED MODERATE CONVECTION IS FROM
4N-8N BETWEEN 34W-41W. SCATTERED MODERATE TO STRONG CONVECTION
IS FROM 7N-9N BETWEEN 49W-53W.

...DISCUSSION...

GULF OF MEXICO...
UPPER LEVEL DIVERGENCE ASSOCIATED WITH AN UPPER LEVEL RIDGE OVER
MEXICO IS SUPPORTING SCATTERED SHOWERS AND THUNDERSTORMS OVER
THE SW GULF S OF 24N W OF 93W. ALSO...ATMOSPHERIC INSTABILITY
ASSOCIATED WITH AN UPPER LEVEL TROUGH OVER THE W ATLC AND SE
GULF IS RESULTING IN SCATTERED SHOWERS AND THUNDERSTORMS FROM
24N-29N BETWEEN 82W-90W INCLUDING PORTIONS OF THE S FLORIDA
PENINSULA. THIS ACTIVITY IS ALSO BEING SUPPORTED BY LOW LEVEL
CONVERGENCE NEAR A 1010 MB SURFACE LOW OVER SE LOUISIANA NEAR
31N91W...AS WELL AS LOW LEVEL CONFLUENCE ACROSS PORTIONS OF THE
CENTRAL AND E GULF. BETWEEN THE TWO AREAS OF SHOWERS AND
THUNDERSTORMS...SUBSIDENCE AND DEEP LAYER DRY AIR ACROSS
PORTIONS OF THE NW AND SOUTH CENTRAL GULF ARE RESULTING IN
GENERALLY FAIR WEATHER. THIS SUBSIDENCE IS SUPPORTING A 1012 MB
SURFACE HIGH OVER THE CENTRAL GULF NEAR 25N89W.

CARIBBEAN SEA...
A BROAD UPPER LEVEL RIDGE IS AFFECTING MUCH OF THE CENTRAL AND E
CARIBBEAN. UPPER LEVEL DIVERGENCE ASSOCIATED WITH THIS RIDGE IS
COMBINING WITH DEEP LAYER MOISTURE OVER THE SW CARIBBEAN TO
RESULT IN SCATTERED SHOWERS AND THUNDERSTORMS S OF 16N W OF 76W
INCLUDING PORTIONS OF NICARAGUA AND PANAMA. ACROSS MUCH OF THE
NW AND E CARIBBEAN...DEEP LAYER DRY AIR IS RESULTING IN
GENERALLY FAIR WEATHER. NE TO E WINDS OF 15 TO 20 KT ARE
OCCURRING ACROSS MUCH OF THE CARIBBEAN.

ATLANTIC OCEAN...
AN UPPER LEVEL TROUGH OVER THE W ATLC AND SE GULF OF MEXICO IS
ASSOCIATED WITH A SURFACE TROUGH EXTENDING FROM 31N68W TO 28N74W
27N79W. LOW LEVEL CONVERGENCE NEAR THE SURFACE TROUGH...AS WELL
AS ATMOSPHERIC LIFT IN SOUTHWESTERLY FLOW ALOFT AND UPPER LEVEL
MOISTURE...ARE SUPPORTING SCATTERED SHOWERS AND THUNDERSTORMS
FROM 25N-30N BETWEEN 62W-78W INCLUDING PORTIONS OF THE NW
BAHAMAS. FARTHER TO THE E...GENERALLY FAIR WEATHER IS PRESENT
ACROSS MUCH OF THE CENTRAL AND E ATLC...WHERE SUBSIDENCE IS
OCCURRING NEAR A BROAD SURFACE RIDGE. THIS SURFACE RIDGE IS
ASSOCIATED WITH A 1026 MB SURFACE HIGH NEAR 33N50W AND A 1021 MB
SURFACE HIGH NEAR 28N29W. HOWEVER...AN UPPER LEVEL TROUGH N OF
27N BETWEEN 18W-31W IS SUPPORTING A SURFACE TROUGH THAT EXTENDS
FROM 31N36W TO 27N41W. LOW LEVEL CONVERGENCE IS SUPPORTING
SCATTERED SHOWERS WITHIN 60 NM EITHER SIDE OF THE SURFACE
TROUGH. ALSO...ATMOSPHERIC INSTABILITY ASSOCIATED WITH AN UPPER
LEVEL LOW NEAR 21N50W IS SUPPORTING SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS FROM 19N-23N BETWEEN 53W-57W. ACROSS THE
TROPICAL ATLC...AN UPPER LEVEL RIDGE AXIS EXTENDS FROM 15N14W TO
10N28W TO 7N44W. UPPER LEVEL DIVERGENCE ASSOCIATED WITH THE
UPPER LEVEL RIDGE IS SUPPORTING CONVECTION ASSOCIATED WITH THE
ITCZ AND THE TROPICAL WAVE THAT EXTENDS FROM 13N31W TO 9N32W TO
4N33W.

$$
COHEN




This weather bulletin was brought to you by:
www.nashvilleweather.net