[Tropical] Tropical Weather Discussion

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AXNT20 KNHC 231738
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT MON 23 MAY 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...TROPICAL WAVES...

CENTRAL ATLC TROPICAL WAVE ALONG 40W S OF 11N MOVING W 10-15 KT.
THERE ARE ACTUALLY AN ASSORTMENT OF LOW-LEVEL CIRCULATIONS
HUGGING THE ITCZ BETWEEN 35W-55W...BUT THE BROAD CURVED
SIGNATURE AROUND 40W HAS BEEN THE TRACKABLE FEATURE AND IS
ASSUMED TO BE THE WAVE POSITION. WIDELY SCATTERED MODERATE
CONVECTION S OF 7N TO THE ITCZ AHEAD OF THE WAVE BETWEEN 43W-47W.

E CARIBBEAN TROPICAL WAVE ALONG 63W/64W S OF 14N MOVING W 15 KT.
VISIBLE IMAGERY SUGGEST A WEAK ROTATION OVER THE FAR SE
CARIBBEAN WATERS...NEAR ISLA DE MARGARITA...BUT AS DISCUSSED
YESTERDAY THIS WAVE IS PRIMARILY ALOFT FROM THE SFC AND IS
CAUSING LITTLE SIGNIFICANT WEATHER.

TROPICAL WAVE ALONG 85W HAS MOVED W OF THE AREA.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 12N10W 9N20W 1N45W 5N60W. SCATTERED
MODERATE/STRONG CONVECTION WITHIN 90 NM N OF THE AXIS STRETCHING
FROM SW MALI TO WRN GUINEA. SCATTERED MODERATE WITHIN 120 NM N
AND 240 NM S OF THE AXIS BETWEEN 16W-26W...AND 145 NM OFF THE
COAST OF LIBERIA. WIDELY SCATTERED MODERATE WITHIN 200 NM OF THE
AXIS BETWEEN 26W-46W. SCATTERED SHOWERS MOVING INLAND N OF THE
AMAZON DELTA.

...DISCUSSION...

GULF OF MEXICO...
MOSTLY FAIR SKIES DOMINATE THE ENTIRE GULF REGION WITH ONLY
ISOLATED CUMULUS AND A FEW HIGH WISPY CLOUDS STREAMING FROM THE
ISTHMUS OF TEHUANTEPEC TOWARDS FLORIDA. A SHARP UPPER TROF HAS
BECOME NEARLY STATIONARY OVER THE AREA WITH AXIS FROM THE BIG
BEND OF FLORIDA SW TO NEAR VERACRUZ AND MEXICO CITY...AND HAS
PROPELLED THE SUBTROPICAL JET NWD INTO THE E GULF (THE REASON
FOR THE HIGH CLOUDS OVER FLORIDA). THE TROF WILL PUSH A COLD
FRONT CURRENTLY LOCATED OVER THE MISSISSIPPI VALLEY SWD OFF THE
N GULF COAST TOMORROW MORNING WITH THE POSSIBILITY OF ISOLATED
SHOWERS/TSTMS CROSSING THE FLORIDA PENINSULA THRU THE DAY. HIGH
PRES AND A DRIER TOTAL ATMOSPHERE WILL KEEP THE W GULF GENERALLY
DRY FOR MUCH OF THE WEEK.

FLORIDA AND WEST ATLANTIC...
A BROADENING MID/UPPER LEVEL TROF HAS BECOME ALMOST STATIONARY
OFF THE NEW ENGLAND COAST AND MORE OR LESS ZONAL FLOW HAS SET UP
FROM FLORIDA EWD TO 60W. THE FLOW CONTINUES TO PUSH A COLD FRONT
ACROSS THE AREA...EXTENDING FROM 32N58W 25N65W 24N72W...THEN AS
A DISSIPATING STATIONARY FRONT ACROSS THE NRN BAHAMAS AND S
FLORIDA. A WEAK 1011 MB LOW IS ATTACHED TO THE TAIL END OF THE
FRONT NEAR MIAMI AND IS CONTRIBUTING TO A MESOSCALE WIND PATTERN
OVER THE SRN PART OF THE FL PENINSULA. ALTHOUGH THE FRONT IS
EXTREMELY WEAK...IT DECEPTIVELY TRIGGERED SHALLOW SHOWER
ACTIVITY YESTERDAY AND OVERNIGHT...PRODUCING OVER 1/2" OF RAIN
IN ISOLATED AREAS. THERE IS NO REASON TO DOUBT THAT SIMILAR
ACTIVITY COULD RE-FORM LATER THIS AFTERNOON...ESPECIALLY AS THE
BOUNDARY INTERACTS WITH THE DIURNAL SEA BREEZE CIRCULATION.

CARIBBEAN...
AN ELONGATED AREA OF LOW PRES...1009 MB...JUST WILL NOT BUDGE
OVER THE W CARIBBEAN WATERS. THE LOW IS CURRENTLY CENTERED NEAR
16.5N78.5W WITH A TROF EXTENDING SW TO COSTA RICA...AND NE
ACROSS KINGSTON JAMAICA TO SRN HAITI. THIS BOUNDARY IS PRODUCING
SCATTERED MODERATE CONVECTION OVER JAMAICA FROM 16N-19N BETWEEN
71W-78W AND OVER THE SW CARIBBEAN S OF 12N BETWEEN 74W-83W.
ANOTHER TROF ORIGINATING FROM THE CNTRL ATLC WATERS ENTERS THE
AREA ACROSS THE U.S. VIRGIN ISLANDS TO 16N70W AND IS ALSO
PRODUCING SCATTERED MODERATE CONVECTION FROM 16N-19N BETWEEN
62W-70W...SOME OF WHICH IS MOVING OVER PUERTO RICO AND THE
VIRGIN ISLANDS. AN EXPANSIVE UPPER LEVEL HIGH IS LOCATED S OF
HISPANIOLA NEAR 16N72W AND IS DRAWING LARGE AMOUNTS OF MOISTURE
NWD OVER THE W CARIBBEAN...WHILE KEEPING THE SRN LEEWARD/
WINDWARD ISLANDS MOSTLY DRY. A PATTERN CHANGE IS EXPECTED OVER
THE NEXT 48-72 HRS AS DEEPER ELY TRADE FLOW BECOMES ESTABLISHED
AND THE WEATHER RETURNS TO ITS CLIMATOLOGICAL NORM.

CENTRAL/EAST ATLANTIC...
A COMPLEX AREA OF LOW PRES IS BECOMING MORE CONSOLIDATED OVER
THE CNTRL ATLC WATERS...WITH 1004 AND 1005 MB LOWS CENTERED NEAR
30N54W AND 27N55W RESPECTIVELY. THE SRN LOW IS ATTACHED TO A
TROF WHICH EXTENDS SW TO THE U.S. VIRGIN ISLANDS...AND EWD TO
28N46W. SCATTERED MODERATE CONVECTION IS E OF THE LOWS N OF 24N
BETWEEN 44W-52W AS WELL AS UP TO 180 NM SE OF THE TRAILING TROF.
THE SYSTEM IS BEING FORCED BY A MID-LEVEL SHORTWAVE ALONG 50W
AND IS EXPECTED TO DEEPEN OVER THE NEXT 24 HRS WITH GALE
CONDITIONS DEVELOPING WITHIN 360 NM TO ITS E/SE. ELSEWHERE IN
THE UPPER LEVELS...AN AMPLIFIED RIDGE EXTENDS FROM THE NRN
LEEWARD ISLANDS NEWD TO 32N43W WITH AN EQUALLY SHARP TROF
FARTHER E ALONG 32N28W 18N31W. NLY FLOW PLUNGING DOWN THE W SIDE
OF THE TROF IS REACHING ALL THE WAY INTO THE TROPICS AND IS
PUSHING MOST OF THE AVAILABLE HIGH LEVEL MOISTURE S OF THE ITCZ
BETWEEN 30W-50W. A SECOND UPPER RIDGE IS BUILDING NWD ALONG THE
COAST OF W AFRICA AND IS PRODUCING A DIFFLUENT UPPER LEVEL
PATTERN S OF THE CAPE VERDE ISLANDS. AFRICAN DUST CONTINUES TO
LINGER OVER THE PART OF THE ATLC...GENERALLY E OF A LINE FROM
20N44W TO 5N35W.

$$
BERG


WWWW
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