[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 281042
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT THU 28 APR 2005

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHEASTERN
SECTIONS OF SOUTH AMERICA...AND 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1015 UTC.

...ITCZ...

ITCZ AXIS IS ALONG 8N1W 3N40W 3N55W.  SCATTERED
MODERATE/ISOLATED STRONG CONVECTION FROM 2N-5N BETWEEN 15W-18W.
WIDELY SCATTERED SHOWERS/THUNDERSTORMS FROM 1N-7N BETWEEN
27W-36W.

...DISCUSSION...

GULF OF MEXICO...
DEEP LAYERED TROUGH MOVING OFF THE E COAST OF THE UNITED STATES
WITH MIDDLE TO UPPER LEVEL RIDGING NOW BUILDING ACROSS THE AREA
IN ITS WAKE. COLD FRONT OVER THE W ATLC TRAILS SWD INTO THE
FLORIDA STRAITS WHERE IT BECOMES DISSIPATING STATIONARY TO THE N
TIP OF THE YUCATAN PENINSULA. SCATTERED SHOWERS ARE WITHIN 90 NM
EITHER SIDE OF THE FRONTAL BOUNDARY.  BEHIND THE FRONT...
CONFLUENT FLOW ALOFT AND DRY LOW LEVEL AIR FILTERING SWD IS
CREATING NEARLY CLOUD FREE CONDITIONS OVER THE E GULF AND
FLORIDA SAVE SOME STREAKS OF HIGH CLOUDS.  HOWEVER...EXPECT THIS
AIRMASS TO BE QUICKLY MODIFIED AS A POST-FRONTAL HIGH...
CURRENTLY OVER THE SE UNITED STATES...MOVES INTO THE W ATLC
WATERS DURING THE NEXT 24 HOURS ESTABLISH ELY FLOW OFF THE ATLC
WATERS BY FRI.  THIS SHOULD ALLOW SOME INCREASE IN LOW LEVEL
MOISTURE AND CLOUDINESS.  OVER THE W GULF...THE FLOW HAS ALREADY
VEERED TO THE SE AND SHOULD INCREASE THROUGH THE END OF THE WEEK
AHEAD OF THE NEXT COLD FRONT WHICH IS SCHEDULED TO ENTER THE
GULF EARLY SAT.  CURRENTLY...BEST LOW LEVEL MOISTURE CONVERGENCE
AND UPPER SUPPORT ARE FORECAST TO OCCUR OVER THE N CENTRAL AND
EASTERN GULF N OF 25N.  FRONT WILL LIKELY HAVE LESS SWD PUSH
THAN THE PREVIOUS 2 SYSTEMS.

CARIBBEAN SEA...
EARLIER CELLS OF MODERATE CONVECTION OVER BELIZE AND THE YUCATAN
PENINSULA HAVE DISSIPATED WITH ONLY SOME HIGH LEVEL DEBRIS
CLOUDINESS REMAINING.  ELSEWHERE....PERSISTENT CLOUDINESS AND
SHOWERS CONTINUE OVER HISPANIOLA MAINTAINING THE WET PATTERN
DURING THE LAST SEVERAL DAYS.  EXPECT THIS ACTIVITY TO REMAIN
THROUGH EARLY FRI WHEN A WEAK FRONT MOVING OVER THE ATLC WATERS
PROVIDES SOME DRYING OVER THE WEEKEND. FURTHER E...SCATTERED
SHOWER ACTIVITY MOVING ACROSS THE LEEWARD AND WINDWARD ISLANDS
HAS BEEN HAVING TROUBLE MAKING MUCH WESTWARD PROGRESS APPARENTLY
DUE TO VERY DRY CONDITIONS IN PLACE OVER THE CENTRAL TO E
CARIBBEAN.  IN THE UPPER LEVELS...MIDDLE TO UPPER LEVEL RIDGE
OVER S AMERICA EXTENDS E/W ALONG 10N/11N WITH A SECOND RIDGE
BUILDING EWD OVER CENTRAL AMERICA ALONG 16N.  THIS PATTERN
CONTINUES TO SUPPORT DEEP CONVECTIVE ACTIVITY OVER N COLOMBIA
WITH ISOLATED CELLS OF MODERATE CONVECTION BEGINNING TO FORM
OVER PANAMA/COSTA RICA.

ATLANTIC OCEAN...
MAIN WEATHER MAKER TODAY IS A DEEP LAYERED TROUGH MOVING OFF THE
E COAST OF THE UNITED STATES WITH ASSOCIATED COLD FRONT ENTERING
THE AREA ALONG 32N69W SW ACROSS THE N BAHAMAS WHERE THE FRONT
BECOMES DISSIPATING STATIONARY THROUGH THE FLORIDA STRAITS.  THE
STRONGEST LIFT/DYNAMICS IS FOCUSED NE OF THE BAHAMAS WITH
SCATTERED MODERATE CONVECTION WITHIN 150 NM E OF A PRE-FRONTAL
TROF FROM 32N67W TO 25N73W.  ELSEWHERE AHEAD OF FRONT...WIDELY
SCATTERED SHOWERS ARE WITHIN 300 NM E OF BOUNDARY.  BEHIND THE
FRONT...DRY AIR THROUGH ALL LEVELS OF THE ATMOSPHERE IS
FILTERING SWD PRODUCING RAPIDLY CLEARING CONDITIONS. THE
REMAINDER OF THE W ATLC REMAINS TRANQUIL WITH A SURFACE RIDGE
EXTENDING FROM 32N55W TO THE S BAHAMAS.  OVER THE CENTRAL
ATLC...A TROUGH TRAILS SWD FROM A 1005 MB LOW N OF THE AREA NEAR
ALONG 32N32W 25N40W 23N46W. A NARROW BAND OF SCATTERED
SHOWERS/ISOLATED THUNDERSTORMS EXIST WITHIN 30 NM EITHER SIDE OF
THE TROUGH.  WIDELY SCATTERED SHOWERS ARE ALSO NOTED WITHIN 30
NM EITHER SIDE OF DISSIPATING COLD FRONT ALONG 32N35W TO
27N45W.  OVER THE E ATLC...BROAD/FLAT TROUGH IS PRODUCING MAINLY
CONFLUENT AND DRY CONDITIONS W OF THE CAPE VERDE ISLANDS.
FINALLY OVER THE TROPICAL ATLC...E/W ORIENTED UPPER RIDGE IS
BUILDING WESTWARD FROM AFRICA ALONG 5N/6N. EXPECT THIS RIDGE TO
PREVAIL THROUGH THE NEXT SEVERAL DAYS WITH A WELL DEFINED
ANTICYCLONE JUST S OF THE CAPE VERDE ISLANDS BY THE WEEKEND.
THIS PATTERN WOULD TEND TO SUPPORT ENHANCED ITCZ CONVECTION
ESPECIALLY NEAR THE SW PERIPHERY OF THE ANTICYCLONE.

$$
RHOME



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