000
AXNT20 KNHC 121741
TWDAT 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT MON MAY 12 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1715 UTC.

...TROPICAL WAVES...
TROPICAL WAVE IS ALONG 53W S OF 9N MOVING W 10-15 KT. THE WAVE 
IS FAIRLY ILL-DEFINED WITH VIS IMAGERY AND 09Z QSCAT DATA 
SHOWING LOW-LEVEL NE FLOW ACROSS THE ANALYZED AXIS. 
HOWEVER...THIS FEATURE IS LIKELY ENHANCING CONVECTION WHICH HAS 
INCREASED IN INTENSITY AND COVERAGE...SCATTERED MODERATE IN 
NATURE...WITHIN 120 NM W AND 180 NM E OF THE AXIS FROM 5N-7N.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 7N11W 2N25W 3N40W 4N51W. NUMEROUS 
MODERATE AND EMBEDDED SCATTERED STRONG CONVECTION IS FROM 3N-8N 
E OF 21W. SCATTERED MODERATE CONVECTION IS FROM 6N-8N BETWEEN 
30W-46W AND S OF 1N BETWEEN 34W-43W. 

...DISCUSSION...

GULF OF MEXICO...
A DEEP LAYER LOW PRES SYSTEM OVER THE MID-ATLANTIC STATES HAS AN 
ASSOCIATED COLD FRONT THAT CUTS ACROSS S FLORIDA TO NEAR 26N85W 
WHERE IT THEN BECOMES STATIONARY TO NEAR BROWNSVILLE TEXAS. THE 
FRONT IS ACCOMPANIED BY A WELL DEFINED ROPE CLOUD LINE AND 
EMBEDDED ISOLATED SHOWERS. COOLER AND MUCH DRIER AIR HAS BUILT S 
BEHIND THE FRONT...GIVING THE REGION MUCH MORE PLEASANT WEATHER 
CONDITIONS THAT THE PAST COUPLE OF DAYS. HOWEVER...THE 
ASSOCIATED N 15-20 KT WINDS N OF THE FRONT IN THE E GULF HAS 
INCREASED SEAS SLIGHTLY TO 6 FT. THIS FRONT IS EXPECTED TO SWEEP 
S THROUGH THE REMAINDER OF THE E GULF BUT LIFT BACK N IN THE 
CENTRAL AND W GULF AS THE UPPER TROUGHING SHIFTS E ALLOWING A 
MID-UPPER RIDGE CENTERED OVER THE NW CARIBBEAN TO GAIN 
CONTROL.    

CARIBBEAN SEA...
A SPRAWLING MID TO UPPER RIDGE IS CENTERED OVER THE GULF OF 
HONDURAS WHILE UPPER TROUGHING EXTENDS FROM THE NRN LEEWARD 
ISLANDS TO THE N COAST OF COLOMBIA. THIS PATTERN IS PRODUCING A 
VERY STABLE ENVIRONMENT ALOFT SUPPRESSING THE DEVELOPMENT OF 
DEEP CLOUDINESS/CONVECTION...AND EVEN THE LOW-LEVEL MOISTURE 
FIELD SEEMS FAIRLY THIN. A QSCAT PASS AROUND 11Z SHOWED AN AREA 
OF 20 KT TRADES NEAR THE COAST OF COLOMBIA WITH LIGHT TO 
MODERATE E TO SE WINDS NOTED ELSEWHERE. MOISTURE WILL LIKELY  
INCREASE SLIGHTLY OVER THE NEXT COUPLE OF DAYS AS AN ATLC COLD 
FRONT DIVES S TOWARD THE GREATER ANTILLES AND AS A WEAK TROPICAL 
WAVE TRACKS W...POSSIBLY DRAGGING SOME MOISTURE TO THE SRN 
WINDWARDS.
 
ATLANTIC OCEAN...
A LARGE LOW PRES SYSTEM OFF THE MID-ATLANTIC COAST IS 
PRODUCING COLD AND RAINY CONDITIONS THERE AND WLY WINDS TO GALE 
FORCE ON ITS S SIDE W OF THE FRONT...WHICH CURRENTLY EXTENDS 
FROM 32N68W TO S FLORIDA. MOISTURE IS LIMITED ALONG THE 
FRONT...HOWEVER...LIGHTNING DATA IS REVEALING SCATTERED TO 
NUMEROUS TSTM ACTIVITY IN AN UPPER DIFFLUENT ZONE N OF 28N 
BETWEEN 65W-70W. ANOTHER PATCH OF ACTIVITY HAS RECENTLY 
DEVELOPED NEAR THE NW BAHAMAS FROM 25N-27N BETWEEN 74W-76W. THE 
LARGE LOW IS EXPECTED TO REMAIN STRONG OVER THE NEXT DAY OR TWO 
PUSHING THE FRONT TOWARD THE SE BAHAMAS AND THE GREATER ANTILLES 
BY TUE AND WED.

A 1025 MB SFC HIGH PRES SYSTEM CENTERED NEAR 29N31W DOMINATES 
THE REMAINDER OF THE REGION PRODUCING MODERATE TRADES ACROSS THE 
TROPICAL BELT. IN THE UPPER LEVELS...THE PATTERN IN THE 
SUBTROPICS IS FAIRLY FLAT DUE TO WEAK RIDGING AND INTERRUPTIONS 
FROM A SERIES OF SHORTWAVES. THESE SHORTWAVES ARE SUPPORTING A 
PAIR OF FRONTAL BOUNDARIES...WHICH BOTH REMAIN N OF THE AREA. 
THIS OVERALL PATTERN IS KEEPING DEEP MOISTURE MINIMAL. BROAD 
RIDGING COVERS THE TROPICS WITH AN EMBEDDED ANTICYCLONE CENTERED 
NEAR 8N28W. UPPER DIFFLUENCE ALONG THE SE AND SW PERIPHERIES OF 
THE RIDGE IS ENHANCING CONVECTION IN THE ITCZ. 

$$
CANGIALOSI