[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 191136
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST SAT 19 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1115 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 12N0 5N10W EQ20W EQ30W 4S45W. WIDELY
SCATTERED MODERATE S OF 6N BETWEEN 9W-18W...CONCENTRATED UP TO
175 NM OFF THE COAST OF SIERRA LEONE. WIDELY SCATTERED MODERATE
S OF 3N BETWEEN 20W-25W. SCATTERED MODERATE WITHIN 45 NM OF A
LINE 4N23W 4N30W 2N35W. NUMEROUS MODERATE/STRONG S OF 2N BETWEEN
43W-53W EXTENDING ALONG THE N COAST OF BRAZIL.

...DISCUSSION...

GULF OF MEXICO...
WEAK 1020 MB HIGH PRES IS CENTERED OVER SW GA AND IS PRODUCING
PREDOMINANTLY WEAK SFC FLOW OVER THE AREA...AS WELL AS AN
ABUNDANCE OF CLEAR SKIES AND COOLER TEMPERATURES AS COMPARED TO
EARLIER THIS WEEK. SLY RETURN FLOW CONTINUES TO PRODUCE PATCHY
AREAS OF LOW CLOUDS ABOUT 250/275 NM OFF THE MX/TX COASTS BUT
OVERALL THIS AREA DOES APPEAR TO BE ERODING AS IT DRIFTS N. A
WEAKENING SHORTWAVE DISTURBANCE IS SCOOTING EWD OFF THE TX COAST
AND IS PRODUCING MAINLY MID/UPPER LEVEL CLOUDINESS OVER THE NW
GULF WATERS. ISOLATED SHOWERS/TSTMS ASSOCIATED WITH A COLD FRONT
OVER E/CNTRL TX SHOULD REMAIN N OF THE GULF WATERS BUT THERE IS
A POTENTIAL FOR WIDELY SCATTERED SHOWERS/TSTMS TO DEVELOP
FARTHER S OVER THE GULF WATERS ON SUN AS A SECOND MID-LEVEL
DISTURBANCE MOVES OFF THE TX COAST EARLY IN THE DAY. THE NEXT
COLD FRONTAL PASSAGE OFF THE COAST DOES NOT APPEAR LIKELY UNTIL
TUE MORNING AT THE EARLIEST AND MOISTURE APPEARS TO BE TOO
LIMITED TO SUPPORT MUCH RAINFALL.

CARIBBEAN...
A STRONG MID/UPPER LEVEL RIDGE REMAINS CENTERED OVER THE AREA
EXTENDING FROM NEAR COSTA RICA/NICARAGUA NE PAST THE CNTRL
LESSER ANTILLES INTO THE ATLC AND IS PRODUCING MOSTLY CLEAR
CONDITIONS FOR A MAJORITY OF THE CARIBBEAN BASIN. HOWEVER...A
COLD FRONT IS SLIDING THRU SE CUBA CONTINUING AS A DISSIPATING
STATIONARY FRONT FROM NEAR MONTEGO BAY JAMAICA SW TO THE CNTRL
NICARAGUAN COAST...THEN TO SRN GUATEMALA. THE CONVECTION
TRIGGERED BY THE FRONT LATE YESTERDAY EVENING HAS COLLAPSED AND
LEFT ONLY ISOLATED SHOWERS OVER NRN NICARAGUA AND SE HONDURAS.
SCATTERED SHOWERS WILL HANG AROUND MAINLY OVER LAND THRU EARLY
MON AS THE FRONT DISSIPATES OVER THE W CARIBBEAN.

ATLANTIC...
STRONG MID/UPPER LEVEL RIDGING OVER THE CARIBBEAN WATERS IS
PRODUCING MAINLY W/WSW FLOW OVER THE W ATLC REGION...WITH A WEAK
TROF EXTENDING ALONG 32N54W TO THE S/CNTRL BAHAMAS. THIS FEATURE
IS SUPPORTING A 999 MB SFC LOW 350 NM ENE OF OF BERMUDA AND A
COLD FRONT WHICH EXTENDS SW ALONG 32N59W 25N70W 20N75W. WIDELY
SCATTERED SHOWERS EXTEND UP TO 120 NM SE OF THE FRONT MAINLY N
OF 28N...WITH AN OVERCAST BAND OF LOW CLOUDS/LIGHT SHOWERS
WITHIN 75 NM OF THE BOUNDARY S OF 28N. A POST-FRONTAL TROF IS
SWINGING SWD OVER THE W ATLC ALONG 31N63W 30N70W TO A DEVELOPING
1012 MB LOW OFF THE SOUTH CAROLINA COAST NEAR 32N77W WHICH IS
PRODUCING SCATTERED SHOWERS MAINLY N OF 32N. ELSEWHERE...AN
ELONGATED E/W SFC RIDGE SPANS ACROSS MUCH OF THE CNTRL/ERN ATLC
WITH A 1018 MB HIGH LOCATED ENE OF THE NRN LEEWARD ISLANDS NEAR
21N45W. A DISSIPATING COLD FRONT IS SLIDING INTO THE RIDGE ALONG
32N19W 21N33W BUT THE STRONGEST UPPER LEVEL SUPPORT HAS SHIFTED
WELL TO THE E OVER MOROCCO...MAURITANIA...AND W ALGERIA SO
ALTHOUGH THERE IS EXTENSIVE HIGH CLOUDINESS N OF 25N BETWEEN
10W-30W...THERE IS VIRTUALLY NO LARGE-SCALE PRECIPITATION. PART
OF THE UPPER TROF WHICH IS MOVING INLAND OVER W AFRICA EXTENDS
SWWD INTO THE TROPICS ACROSS THE CAPE VERDE ISLANDS TO 10N50W
AND IS PRODUCING MODERATE SUBSIDENCE WITHIN 150 NM EITHER SIDE
OF ITS AXIS...LARGELY SUPPRESSING ITCZ CONVECTION TO A POSITION
CLOSER TO THE EQUATOR WHERE THERE IS MORE MOISTURE AND UPPER
DIVERGENCE.

$$
BERG



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