[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 180521
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT FRI MAY 18 2007

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN
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...METEOROLOGICAL ANALYSIS...
WEATHER OBSERVATIONS...AND RADAR.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0445 UTC.

...THE ITCZ...

THE ITCZ AXIS IS ALONG 6N9W 5N15W 6N34W 4N52W. SCATTERED
MODERATE/STRONG CONVECTION IS FROM THE EQUATOR TO 3N BETWEEN
1W-7W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION
ARE WITHIN 120/150 NM OF THE ITCZ AXIS ACROSS THE ENTIRE ATLC.

...DISCUSSION...

GULF OF MEXICO...
UPPER RIDGE EXTENDS E/W ACROSS CENTRAL AMERICA AND MEXICO
COVERING THE SW GULF. BROAD UPPER TROUGH DOMINATES THE E US AND
THE REMAINDER OF THE GULF MOVING INTO THE W ATLC. THE ASSOCIATED
FRONTAL BOUNDARY EXTENDS FROM THE W ATLC ACROSS NE FLORIDA TO A
1012 MB LOW OVER FLORIDA NEAR 30N84W WITH A COLD FRONT EXTENDING
INTO THE GULF TO NEAR 26N90W WHERE IT DISSIPATES TO JUST OFF THE
TEXAS COAST NEAR 26N96W. THIS IS A WEAK FRONT AND WITH THE DRY
AIR IN PLACE ONLY WIDELY ISOLATED SHOWERS ARE BEING GENERATED
ALONG THE FRONTAL BOUNDARY. HIGH PRESSURE IS AGAIN BUILDING
BEHIND THE FRONT WITH NORTHERLY WINDS BRIDGING THE FRONT ACROSS
THE ENTIRE GULF. THE FRONT WILL CONTINUE TO DRIFT SLOWLY S
ACROSS THE GULF WITH THE MAIN ENERGY MOVING E INTO THE W ATLC.

CARIBBEAN SEA...
AN UPPER LEVEL TROUGH OVER THE GULF OF MEXICO DIPS INTO THE NW
CARIBBEAN N OF 18N W OF 77W. THIS UPPER TROUGH IS GENERATING
SOME SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS OVER
THE NW CARIBBEAN WITHIN 120 NM OF LINE FROM 19N79W TO 16N84W.
BROAD UPPER LEVEL E/W RIDGE EXTENDS FROM SOUTH AMERICA ACROSS
CENTRAL AMERICA COVERING THE REMAINDER OF THE CARIBBEAN. THE
UPPER RIDGE IS ENHANCING SCATTERED MODERATE/ISOLATED STRONG
CONVECTION WITHIN 120/150 NM OF LINE FROM 19N78W ACROSS CUBA
INTO THE W ATLC NEAR 21N76W. THE 1010 MB LOW ANALYZED NEAR
17N82W HAS DETERIORATED TO A SURFACE TROUGH AT 18/0300 UTC
EXTENDING FROM THE CAYMAN ISLANDS TO OFF THE COAST OF NICARAGUA
NEAR 13N82W. THE ITCZ IN THE E PACIFIC EXTENDS ACROSS
COLOMBIA/PANAMA AND JUST S OF COSTA RICA COUPLED WITH THE 1007
MB LOW ALONG THE COAST OF COLOMBIA NEAR 11N76W ARE GENERATING
SCATTERED MODERATE/ISOLATED STRONG CONVECTION S OF 13N FROM
74W-80W AND S OF 11N W OF 80W TO INLAND OVER CENTRAL AMERICA.
ALTHOUGH SOME HIGH CLOUDS ARE OBSERVED OVER THE E
CARIBBEAN...DRY CONDITIONS DOMINATE THAT AREA TONIGHT.
MODERATE/STRONG EASTERLY TRADE WINDS DOMINATE THE CARIBBEAN.

ATLANTIC OCEAN...
UPPER TROUGH OVER THE GULF OF MEXICO EXTENDS INTO THE W ATLC W
OF 75W WITH THE ASSOCIATED FRONTAL BOUNDARY EXTENDING FROM A
1013 MB LOW ALONG THE SOUTH CAROLINA COAST TO THE 1012 MB LOW
OVER NE FLORIDA. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE
WITHIN 90 NM E OF THE FRONT TO JUST INLAND OVER NE FLORIDA.
EMBEDDED WITHIN THE UPPER TROUGH IS A 1010 MB LOW OVER THE N
BAHAMAS NEAR 27N76W WITH A SURFACE TROUGH EXTENDING TO OVER
CENTRAL CUBA NEAR 22N78W. AN UPPER RIDGE TO THE E IS ENHANCING
SCATTERED MODERATE/ISOLATED STRONG CONVECTION TO THE E OF THE
SURFACE FEATURES WITHIN 150/200 NM OF LINE FROM OVER CUBA NEAR
21N76W ALONG 26N70W TO BEYOND 32N69W. DEEP LAYERED LOW COVERS
THE CENTRAL ATLC N OF 17N BETWEEN 40W-55W WITH THE UPPER LOW
CO-LOCATED WITH THE 1018 MB SURFACE LOW NEAR 29N50W AND A
SURFACE TROUGH EXTENDING S TO 21N52W. THESE FEATURES ARE
EMBEDDED WITHIN DRY AIR AND ARE ONLY ABLE TO GENERATE A NARROW
BAND OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 45 NM OF
A LINE FROM 24N47W-27N46W-29N47W. AN UPPER TROUGH IS OVER THE NE
ATLC EXTENDING FROM OVER MOROCCO TO AN UPPER LOW NEAR 30N20W TO
BEYOND 32N28W COVERING THE AREA N OF 26N. BROAD UPPER RIDGE
EXTENDS E/W ACROSS THE TROPICAL ATLC ALONG 5N/6N TO AN UPPER
HIGH NEAR 6N48W. THIS UPPER RIDGE IS ADVECTING TROPICAL MOISTURE
ACROSS THE E TROPICAL ATLC...HOWEVER DUE TO THE DRY AIR AND
AFRICAN DUST PRESENT NO SHOWERS AND CLOUDS ARE FORMING. AT THE
SURFACE...A RIDGE DOMINATES THE ATLC W OF 65W WITH A WEAKNESS IN
THE CENTRAL ATLC IN THE REGION OF THE DEEP LAYERED LOW.

$$
WALLACE





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