000
AXNT20 KNHC 262344
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT THU MAR 26 2009

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2230 UTC.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 5N8W 3N15W CROSSING THE EQUATOR NEAR 
23W THEN ALONG 1S BETWEEN 26W AND THE NE COAST OF BRAZIL. 
SCATTERED MODERATE TO STRONG CONVECTION IS FROM 2N-5N BETWEEN 
THE COAST OF AFRICA AND 14W. SCATTERED MODERATE CONVECTION IS 
FROM THE EQUATOR TO 4S W OF 26W.
 
...DISCUSSION...

GULF OF MEXICO...
THE COMBINATION OF UPPER LEVEL DIVERGENCE AND LOW-LEVEL 
CONVERGENCE ASSOCIATED WITH A FRONTAL BOUNDARY OVER THE SE CONUS 
IS GENERATING NUMEROUS SHOWERS AND THUNDERSTORMS OVER THE NE 
GULF FROM MOBILE BAY TO THE FLORIDA BIG BEND REGION. SATELLITE 
AND LIGHTNING DATA INDICATE THESE STORMS EXTEND AS FAR SOUTH AS 
28N. SOME OF THIS ACTIVITY MAY BE SEVERE...REFER TO LOCAL NWS 
PRODUCTS FOR MORE INFORMATION. AS OF 2100 UTC...A SQUALL LINE 
IS ALONG 31N84W 29N85W TO 29N87W. THUNDERSTORMS MOVING AHEAD OF 
A DRY LINE OVER TEXAS ARE BEGINNING TO IMPACT THE NW GULF ALONG 
THE COAST FROM LAGUNA MADRE TO THE TEXAS/LOUISIANA BORDER. APART 
FROM THE CONVECTIVE ACTIVITY...STRONG SOUTHERLY WINDS OF 20 TO 
25 KT ARE BEING FUNNELED ACROSS THE GULF BETWEEN A SFC RIDGE 
OVER THE W ATLC AND A SFC TROUGH THAT EXTENDS FROM THE CENTRAL 
CONUS ACROSS EASTERN MEXICO TO THE BAY OF CAMPECHE.LOOKING 
AHEAD...A STRONG COLD FRONT IS EXPECTED TO MOVE INTO THE NW 
WATERS LATE FRI BRINGING NLY GALE FORCE WINDS W OF THE FRONT 
OVER THE SW WATERS.  

CARIBBEAN SEA...
HIGH PRESSURE OVER THE W ATLC CONTINUES TO PRODUCE FRESH TO 
STRONG TRADE WINDS ACROSS THE CARIBBEAN E OF 83W. ABUNDANT DRY 
AIR IN THE MID TO UPPER LEVELS COVER THE CARIBBEAN NW OF A LINE 
FROM PUERTO RICO TO PANAMA...INHIBITING CONVECTION IN THIS 
REGION. STRONG SWLY FLOW AROUND A BROAD UPPER LEVEL RIDGE OVER 
THE EASTERN CARIBBEAN IS ADVECTING UPPER LEVEL MOISTURE FROM THE 
PACIFIC ACROSS THE SE CARIBBEAN AND LESSER ANTILLES. ISOLATED 
SHOWERS ARE MOVING EASTWARD IN THE TRADE WIND FLOW FROM THE 
LEEWARD ISLANDS TO 77W NORTH OF 14N. LITTLE CHANGE IS EXPECTED 
OVER THE NEXT 24 HOURS.   
 
ATLANTIC OCEAN...
A DEEP-LAYER LOW PRESSURE SYSTEM CONTINUES TO SPIN IN THE N ATLC 
WITH THE 989 MB SFC LOW CENTERED NEAR 38N55W. A PAIR OF SFC 
TROUGHS...PREVIOUSLY COLD FRONTS...ASSOCIATED WITH THIS FEATURE 
EXTEND INTO THE DISCUSSION AREA. THE PRIMARY TROUGH ENTERS THE 
REGION NEAR 31N46W AND CONTINUES ALONG 24N50W 16N56W TO NEAR 
9N60W...JUST NORTH  OF THE GUYANA COAST. A WEAK SFC LOW HAS 
DEVELOPED ALONG THE TROUGH NEAR 23N51W. THIS LOW IS EXPECTED TO 
DISSIPATE WITHIN 24 HOURS. SCATTERED SHOWERS ARE OBSERVED UP TO 
360 NM AHEAD OF THE TROUGH N OF 26N AND WITHIN 150 NM E OF THE 
TROUGH SOUTH OF 26N. THE SECONDARY TROUGH IS POSITIONED ALONG 
31N50W 28N55W TO 27N61W. LITTLE CONVECTION IS ASSOCIATED WITH 
THIS TROUGH. HIGH PRESSURE CONTINUES TO MOVE INTO THE W ATLC IN 
THE WAKE OF THE FRONTS. COLD AIR STRATOCUMULUS CLOUDS ARE 
OBSERVED W OF 54W. FURTHER EAST...A SECOND DEEP-LAYER LOW 
PRESSURE SYSTEM IS LOCATED NW OF THE CANARY ISLANDS. SCATTERED 
SHOWERS ARE WITHIN 240 NM OF THE LOW-CENTER IN THE EASTERN 
SEMI-CIRCLE. UPPER-LEVEL DIVERGENCE AROUND A BROAD RIDGE 
CENTERED NEAR 4N34W IS ENHANCING CONVECTION ALONG THE ITCZ.

$$
WADDINGTON