[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 232328
TWDAT

TROPICAL WEATHER DISCUSSION...
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT WED APR 23 2008

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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2215 UTC.

...THE ITCZ...

ITCZ AXIS IS CENTERED ALONG 6N8W 2N16W 1N30W CROSSING THE
EQUATOR NEAR 43W TO 1S50W. CLUSTERS OF SCATTERED MODERATE/STRONG
CONVECTION ARE FROM 3N-6N E OF 13W ACROSS THE PRIME MERIDIAN AND
INLAND OVER SW AFRICA. CLUSTERS OF SCATTERED MODERATE CONVECTION
ARE FROM 1N-5N BETWEEN 35W-52W.

...DISCUSSION...

GULF OF MEXICO...
A BROAD UPPER RIDGE DOMINATES THE W GULF ANCHORED IN THE E
PACIFIC REGION WITH THE AXIS EXTENDING ACROSS MEXICO AND INTO
THE CENTRAL PLAIN STATES. A SURFACE RIDGE EXTENDS FROM OVER THE
SE US WITH A WEAK 1019 MB HIGH REMAINING IN THE N GULF NEAR
28N89W. A BROAD UPPER TROUGH COVERS THE REMAINDER OF THE GULF E
OF 88W ACROSS FLORIDA AND INTO THE W ATLC WHERE AN UPPER LOW IS
NE OF THE BAHAMAS. THE GULF REMAINS RATHER QUIET THIS EVENING.
THE SURFACE RIDGE WILL BEGIN TO SHIFT EASTWARD LATE THU WITH
RETURN FLOW EXPECTED OVER THE W GULF AND THE NEXT FRONT IS
EXPECTED TO ENTER THE GULF LATE IN THE WEEKEND.

CARIBBEAN SEA...
THE UPPER TROUGH OVER THE E GULF EXTENDS INTO THE NW CARIBBEAN N
OF THE CAYMAN ISLANDS E OF THE WINDWARD PASSAGE. THE REMAINDER
OF THE CARIBBEAN IS DOMINATED BY UPPER WESTERLY FLOW GENERATED
BY THE E/W UPPER RIDGE THAT EXTENDS FROM THE TROPICS ACROSS
SOUTH AMERICA SPREADING THIN HIGH CLOUDS MAINLY OVER THE FAR S
CARIBBEAN S OF 13N E OF 80W. MODERATE EASTERLY TRADE WINDS COVER
THE AREA RESULTING FROM THE WEAK PRESSURE GRADIENT OVER THE ATLC
WATERS. AFTERNOON SHOWERS/ISOLATED THUNDERSTORMS HAVE GENERATED
OVER PORTIONS OF HISPANIOLA AND ARE DRIFTING N INTO THE W ATLC
COASTAL WATERS. HOWEVER WITH THE STRONG SUBSIDENCE AND DRY AIR
THAT DOMINATES THE CARIBBEAN...THIS ACTIVITY WILL DIMINISH LATER
TONIGHT. OTHERWISE THE CARIBBEAN REMAINS RATHER QUIET THIS
EVENING.

ATLANTIC OCEAN...
BROAD UPPER TROUGH THAT COVERS THE E GULF OF MEXICO EXTENDS OVER
THE W ATLC INTO THE CENTRAL ATLC WITH AN UPPER LOW NEAR 28N72W
AND A 1010 MB SURFACE LOW NEAR 29N73W. A SURFACE TROUGH EXTENDS
S TO OVER THE BAHAMA ISLANDS NEAR 22N75W WITH SCATTERED
SHOWERS/ISOLATED THUNDERSTORMS TO THE E WITHIN 45/60 NM OF LINE
FROM 23N73W TO 27N69W. A SECOND SURFACE 1010 MB LOW IS TO THE E
NEAR 28N69W WITH A SURFACE TROUGH EXTENDING ALONG 27N66W TO NEAR
23N68W. SCATTERED SHOWERS/THUNDERSTORMS ARE FROM 28N-31N BETWEEN
67W-72W WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED
THUNDERSTORMS WELL TO THE E OF THIS SURFACE TROUGH WITHIN 75 NM
OF LINE FROM 23N64W TO 28N58W. AFTERNOON SHOWERS/ISOLATED
THUNDERSTORMS HAVE GENERATED INLAND OVER PORTIONS OF HISPANIOLA
AND ARE DRIFTING N OVER THE IMMEDIATE COASTAL WATERS. A STRONG
UPPER LOW IS OVER THE N/CENTRAL ATLC WITH AN ASSOCIATED COLD
FRONT APPROACHING THE REGION AND A SURFACE TROUGH EXTENDING INTO
THE REGION NEAR 32N44W TO 25N50W. ISOLATED SHOWERS ARE WITHIN
150 NM E OF THIS TROUGH. A LARGE UPPER RIDGE IS OVER THE
REMAINDER OF THE CENTRAL ATLC INTO THE E ATLC EXTENDING FROM AN
UPPER HIGH NEAR 11N43W NE TO BEYOND 32N21W. A LARGE SURFACE
RIDGE DOMINATES THE E ATLC N OF 20N E OF 45W ANCHORED BY A 1027
MB HIGH N OF THE MADEIRA ISLANDS. THUS FAIR WEATHER SKIES COVER
THE E ATLC. THE TYPICAL E/W UPPER RIDGE AXIS EXTENDS ACROSS THE
TROPICS AND SOUTH AMERICA.

$$
WALLACE


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