[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 240545
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST WED DEC 24 2008

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0445 UTC.

...THE ITCZ...
ITCZ IS ANALYZED ALONG 9N10W 5N19W 2N42W THEN S OF THE EQUATOR
NEAR 48W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS
WITHIN 45 NM OF LINE FROM 7N34W TO 6N36W. SCATTERED MODERATE
WITH EMBEDDED OF ISOLATED STRONG CONVECTION COVERS THE AREA
WITHIN 60 NM N OF THE ITCZ FROM 17W-27W.

...DISCUSSION...

GULF OF MEXICO...
A DEEP LAYERED TROUGH EXTENDS FROM THE THE CENTRAL US TO OVER
TEXAS AND N MEXICO WITH THE ACCOMPANYING FRONTAL BOUNDARY
REMAINING WELL INLAND. THIS WEAK FRONT IS EXPECTED TO ENTER THE
NW GULF LATE WED PULLING N ACROSS THE N GULF COAST WITH THE NEXT
MAJOR FRONT TO CROSS THE GULF ENTERING LATE SAT. CURRENTLY A
WEAK CONVERGENCE SURFACE TROUGH EXTENDS FROM GALVESTON TEXAS S
TO 22N53W WITH BROKEN LOW CLOUDS AND ISOLATED SHOWERS W OF THE
TROUGH TO INLAND OVER TEXAS. AN UPPER RIDGE EXTENDS OVER THE
GULF FROM THE CARIBBEAN WITH MODERATE/STRONG SUBSIDENCE AND DRY
STABLE AIR NOTED ACROSS THE GULF WATERS MAINLY S OF 26N. THE
SURFACE RIDGE COVERS THE GULF ANCHORED OFF THE CAROLINA/VIRGINA
COAST. BROKEN/OVERCAST LOW CLOUDS WITH ISOLATED SHOWERS IS FROM
23N-26N E OF 86W ACROSS S FLORIDA AND THE FLORIDA STRAITS.
OTHERWISE THE REMAINDER OF THE GULF REMAINS TRANQUIL TONIGHT.

CARIBBEAN SEA...
THE CARIBBEAN REMAINS UNDER THE INFLUENCE OF A BROAD UPPER HIGH
CENTERED NEAR THE ABC ISLANDS AND ENCOMPASSES THE ENTIRE
CARIBBEAN BASIN WITH STRONG SUBSIDENCE AND DRY AIR. THIS UPPER
LEVEL FEATURE ALSO ENVELOPS CENTRAL AMERICA AND THE N PORTION OF
SOUTH AMERICA INTO THE W TROPICAL ATLC. HOWEVER...AREAS OF
SHALLOW LOW LEVEL MOISTURE CONTINUES TO STREAM ACROSS THE BASIN
USHERED IN ON STRONG NE-E TRADE WINDS WITH ISOLATED SHOWERS
DOTTING MOST OF THE ENTIRE CARIBBEAN INCLUDING THE LESSER
ANTILLES. THE STRONG HIGH PRESSURE TO THE N IS SHIFTING E
MAINTAINING THE STRONG TRADE WINDS THROUGH THE WEEKEND.

ATLANTIC OCEAN...
A COLD FRONT ENTERS THE W/CENTRAL ATLC NEAR 32N49W EXTENDING SW
TO 24N65W DISSIPATING AS A STATIONARY BOUNDARY ACROSS THE
CENTRAL BAHAMAS TO THE N COAST OF CUBA NEAR 23N80W. BROKEN/
OVERCAST LOW CLOUDS WITH ISOLATED SHOWERS ARE WITHIN 180 NM NW
OF THE COLD FRONT WITH BROKEN/OVERCAST COLD AIR STRATOCUMULUS
CLOUDS COVERING THE REMAINDER OF THE AREA N OF THE ENTIRE FRONT.
A BROAD UPPER LEVEL RIDGE EXTENDS FROM THE CARIBBEAN WITH AXIS
ACROSS PUERTO RICO NE TO BEYOND 27N42W. AN UPPER LEVEL LOW
COVERS THE E ATLC N OF 20N E OF 30W TO THE COAST OF W AFRICA AND
CENTERED NEAR 32N21W WITH A COLD FRONT ENTERING THE AREA NEAR
32N17W TO 29N20W DISSIPATING TO NEAR 28N33W. A UPPER SHEAR AXIS
EXTENDS FROM THE UPPER LOW NEAR 23N30W WSW INTO THE TROPICS
ALONG 16N40W TO 9N50W. UPPER DIFFLUENCE SE OF THIS UPPER
LOW/SHEAR AXIS COUPLED WITH AN UPPER RIDGE AMPLIFIED INLAND OVER
THE W AFRICA IS ENHANCING SCATTERED SHOWERS/ISOLATED
THUNDERSTORMS WITHIN 90/120 NM OF LINE FROM 9N50W TO 11N37W AND
DENSE CLOUD COVER WITH ISOLATED SHOWERS WITHIN 150 NM OF LINE
FROM 11N37W ACROSS THE CAPE VERDE ISLANDS TO THE COAST OF
MAURITANIA NEAR 1816W. STRONG NE TO E TRADE WINDS CONTINUE
ACROSS THE TROPICAL ATLC AND WILL CONTINUE THROUGH FRI.

$$
WALLACE





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