[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 090528
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST WED 09 MAR 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0345 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 6N8W 3N15W 3N30W 4N42W 2N52W.
CLUSTERS OF SCATTERED/NUMEROUS STRONG CONVECTION ARE WITHIN
90/120 NM OF LINE 4N9W-3N18W AND WITHIN 60 NM ALONG THE SW COAST
OF AFRICA E OF 7W ACROSS THE PRIME MERIDIAN. SCATTERED MODERATE/
STRONG CONVECTION IS INLAND AND WITHIN 90 NM ALONG THE COAST OF
AFRICA FROM 6N-9N. CLUSTERS OF SCATTERED MODERATE/ISOLATED
STRONG CONVECTION ARE FROM 5N TO S OF THE EQUATOR BETWEEN
19W-35W AND S OF THE AXIS W OF 47W TO INLAND OVER SOUTH AMERICA.

...DISCUSSION...

GULF OF MEXICO...
THE PATTERN WILL REMAIN VERY ACTIVITY THROUGH THE END OF THE
WEEK AS THE STRONG SOUTHERN STREAM JET WITH WINDS TO 150 KT WILL
STAY NEARLY STATIONARY ACROSS THE SE UNITED STATES AND N GULF
INTO THE W ATLC. AT THE SAME TIME...MULTIPLE SHORTWAVES WILL
CONTINUE TO DROP SE FROM THE CENTRAL UNITED STATES INTERACTING
WITH THE SUBTROPICAL JET AND RESULTING IN QUICK ROUNDS OF
SHOWER/THUNDERSTORM ACTIVITY. CURRENTLY...THE VIGOROUS SHORTWAVE
TROUGH WHICH MOVED INTO THE W ATLC EARLIER TODAY IS NOW QUICKLY
LIFTING NE AWAY FROM THE AREA. ASSOCIATED CLOUDINESS AND SHOWER
ACTIVITY HAS ENDED OVER FLORIDA WITH THE ATTENDANT COLD FRONT
SWEEPS THROUGH THE FLORIDA STRAITS BECOMING STATIONARY N OF THE
YUCATAN CHANNEL EXTENDING INTO THE W BAY OF CAMPECHE AND ALONG
THE E SLOPES OF THE SIERRA MADRE MOUNTAINS. OVERRUNNING ALONG
THE FRONT COUPLED WITH BROAD DIFFLUENT FLOW ALOFT AHEAD OF A
CUT-OFF LOW OVER NW MEXICO IS PRODUCING WIDESPREAD CLOUDINESS
AND SHOWER ACTIVITY OVER THE W GULF. EXPECT THIS PORTION OF THE
FRONT TO BECOME INCREASINGLY MORE ACTIVE AS A SECOND STRONG
SHORTWAVE DROPS RAPIDLY SE FROM THE CENTRAL UNITED STATES AND IS
NOW OVER NW TEXAS. THIS SHORTWAVE SHOULD IGNITE ANOTHER
IMPRESSIVE ROUND OF NUMEROUS SHOWERS/THUNDERSTORMS ALONG A FRONT
BEGINNING LATER THIS MORNING THEN EXPANDING E ACROSS THE S HALF
OF FLORIDA BY WED NIGHT. REINFORCING SURGE OF CONTINENTAL AIR
WITH THE SHORTWAVE WILL KICK THE NOW STATIONARY FRONT OUT THE W
GULF RESULTING IN ANOTHER FRONTAL PASSAGE OVER S FLORIDA INTO
THU. HOWEVER...POST FRONTAL N FLOW AND ASSOCIATED DRYING WILL BE
VERY BRIEF AS GUIDANCE INDICATES YET ANOTHER SHORTWAVE AND FRONT
DROPPING FROM THE CENTRAL UNITED STATES BY THE END OF THE WEEK.

CARIBBEAN...
THE PATTERN REMAINS LESS COMPLEX OVER THE CARIBBEAN AS BROAD
MID/UPPER RIDGING IS EXPECTED TO REMAIN IN PLACE THROUGH THE
NEXT SEVERAL DAYS EFFECTIVE BLOCKING UPSTREAM ENERGY FROM
PENETRATING THE AREA. THE RIDGE AXIS IS CURRENTLY ALIGNED E/W
ALONG 11N/12N WITH MULTIPLE ANTICYCLONIC CENTERS OBSERVED...ONE
NEAR COSTA RICA/NICARAGUA AND ANOTHER ALONG THE N COAST OF
VENEZUELA NEAR THE ABC ISLANDS. MOISTURE IS LARGELY ABSENT
THROUGH ALL LEVELS OF THE ATMOSPHERE RESULTING IN MINIMAL SHOWER
ACTIVITY. THIS DRY AIR SHOULD REMAIN IN PLACE THROUGH TODAY WITH
SOME INCREASE IN LOW LEVEL MOISTURE AHEAD OF A COLD FRONT WHICH
WILL CROSS THE YUCATAN PENINSULA AND W CUBA LATER IN THE DAY.
THERE SHOULD BE JUST ENOUGH UPPER LEVEL ENERGY TO TRIGGER A
BRIEF ROUND OF SHOWERS/THUNDERSTORMS ALONG THE FRONT...MAINLY
OVER W CUBA...EARLY THU. THEREAFTER...THE FRONT QUICKLY LOSES
UPPER SUPPORT WITH ONLY ISOLATED SHOWERS ALONG THE DISSIPATING
BOUNDARY WHICH PULLS UP STATIONARY FROM E CUBA TO HONDURAS BY
LATER IN THE WEEK. ELSEWHERE...DRY/TRANQUIL CONDITIONS ARE
EXPECTED TO PREVAIL THROUGHOUT THE WEEK.

ATLANTIC...
A STRONG COLD FRONT IS THE MAIN WEATHER MAKER OVER THE W ATLC
CURRENTLY EXTENDING W OF BERMUDA NEAR 32N69W TO THE FLORIDA
STRAITS. GOOD DYNAMICS/LIFT AHEAD OF A POTENT SHORTWAVE THAT
EXITED THE E COAST OF THE U.S. EARLIER IS PRODUCING WIDESPREAD
CLOUDINESS AND SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 28N
FROM 57W-68W. GALE CONDITIONS ARE ALSO OBSERVED BOTH AHEAD OF
AND BEHIND THE FRONT DUE TO AN UNUSUALLY STRONG PRESSURE
GRADIENT WITH THIS SYSTEM. THE SHORTWAVE WILL CONTINUE TO LIFT
RAPIDLY NE DURING THE MORNING WITH DECREASING SHOWER/
THUNDERSTORM ACTIVITY ALONG THE FRONT IN THE AREA. SHOWERS/
THUNDERSTORMS INCREASE AGAIN LATE TODAY FROM W TO E ALONG THE
TAIL END OF THE FRONT OVER THE BAHAMAS AS THE UPSTREAM
DISTURBANCE MOVES INTO THE GULF. OVER THE CENTRAL ATLC...AN
UPPER RIDGE AXIS EXTENDING FROM HISPANIOLA TO BEYOND 32N55W
PREVAILS. FINALLY OVER THE E ATLC...A LARGE DEEP-LAYERED
OCCLUDED LOW IS LOCATED N OF THE AREA WITH THE ASSOCIATED UPPER
TROUGH EXTENDING S ALONG 32N38W TO 18N49W. ATTENDANT SURFACE
COLD FRONT ENTERS THE AREA ALONG 32N25W SW TO 17N44W...THEN
DISSIPATING NEAR BARBADOS. THE STRONGEST DYNAMICS/LIFT WITH
THIS SYSTEM IS N OF THE AREA BUT A NARROW BAND OF SCATTERED
MODERATE CONVECTION IS UP TO 200 NM E OF THE FRONT N OF 28N. S
OF 28N...ISOLATED SHOWERS ARE LOCATED WITHIN 60 NM EITHER SIDE
OF FRONT. THE FRONT IS FORECAST TO WEAKEN DURING THE NEXT 24-36
HRS WITH DECREASING SHOWERS/THUNDERSTORM ACTIVITY.

$$
WALLACE


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