000
AXNT20 KNHC 090516
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
105 AM EST TUE MAR 09 2010

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0345 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 7N11W 3N29W 1N44W ACROSS THE EQUATOR 
AND INLAND OVER SOUTH AMERICA NEAR 49W. CLUSTERS OF SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 90 NM EITHER SIDE 
OF THE ITCZ E OF 27W TO INLAND OVER W AFRICA. CLUSTERS OF 
SCATTERED MODERATE CONVECTION ARE WITHIN 60 NM OF LINE FROM 
4N10W 2N18W. 

...DISCUSSION...

GULF OF MEXICO...
THE SURFACE RIDGE THAT HAS DOMINATED THE GULF IS BEGINNING TO 
GIVE WAY AND SHIFT E AS LOWER PRESSURE MOVES INTO THE W GULF. 
THE ASSOCIATED FRONTAL SYSTEM REMAINS INLAND OVER THE SOUTHERN 
PLAIN STATES. THE UPPER RIDGE IS ALSO BEGINNING TO SHIFT E AS A 
SHORTWAVE UPPER TROUGH MOVES OFF THE TEXAS/LOUISIANA COAST. THE 
UPPER RIDGE CONTINUES TO DRAW TROPICAL MOISTURE ACROSS MEXICO 
AND THE GULF FROM THE E PACIFIC GENERATING HIGH CLOUDS ACROSS 
MUCH OF THE AREA. E TO SE SURFACE WINDS ACCOMPANIED BY LOW-LEVEL 
MOISTURE AND INSTABILITY ARE COMBINING TO GENERATE SCATTERED/ 
NUMEROUS SHOWERS MAINLY WITHIN 120 NM OF LINE FROM 25N93W TO 
OVER THE NE GULF COAST NEAR PENSACOLA FLORIDA AND AFFECTING THE 
AREA FROM APALACHICOLA BAY FLORIDA TO ATCHAFALAYA BAY 
LOUISIANA. THE SURFACE RIDGE WILL CONTINUE TO SHIFT E AS THE 
NEXT FRONT IS EXPECTED TO ENTER THE NW GULF WED EVENING WITH A 
SECOND REINFORCING FRONT MOVING INTO THE NW GULF THU NIGHT AND 
WILL MERGE WITH INITIAL FRONT ON FRI MOVING SE OUT OF THE GULF 
LATE FRI NIGHT. 

CARIBBEAN SEA...
A STATIONARY FRONT REMAINS ACROSS THE E CARIBBEAN EXTENDING FROM 
THE CENTRAL ATLC INTO THE E CARIBBEAN THROUGH THE GUADELOUPE 
PASSAGE CONTINUING ALONG 13N72W TO THE COAST OF COLOMBIA NEAR 
11N74W. SCATTERED SHOWERS ARE WITHIN 200 NM NW OF THE FRONT WITH 
ISOLATED SHOWERS WITHIN 120 NM SE OF THE FRONT. THE FRONT IS 
SUPPORTED BY A LARGE UPPER LEVEL TROUGH OVER THE W AND CENTRAL 
ATLC N OF 17N BETWEEN 40W-70W. A SURFACE TROUGH IS ANALYZED OVER 
THE CENTRAL CARIBBEAN FROM SW HAITI NEAR 18N73W 13N77W TO THE 
COAST OF COLOMBIA NEAR 9N77W WITH ISOLATED SHOWERS WITHIN 90/120 
NM W OF THE TROUGH AXIS. THE W CARIBBEAN IS EXPERIENCING 
GENERALLY FAIR WEATHER INFLUENCED BY SURFACE RIDGE OVER THE E 
GULF OF MEXICO. EXPECT THE FRONTAL BOUNDARY TO GRADUALLY DRIFT 
NW BEFORE DISSIPATING WED NIGHT.

ATLANTIC OCEAN...
SURFACE RIDGE OVER THE E GULF OF MEXICO EXTENDS INTO THE W ATLC 
PROVIDING THE AREA GENERALLY FAIR WEATHER. A DEEP LAYER TROUGH 
REMAINS OVER THE W AND CENTRAL ATLC N OF 17N FROM 40W-70W 
SUPPORTING A COLD FRONT THAT ENTERS THE REGION NEAR 32N39W 
EXTENDING ALONG 23N47W BECOMING STATIONARY NEAR 20N51W INTO THE 
NE CARIBBEAN THROUGH THE GUADELOUPE PASSAGE. SCATTERED SHOWERS 
AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 150 NM SE OF THE 
COLD FRONT N OF 28N AND WITHIN 225 NM NW OF THE STATIONARY 
FRONT. A SURFACE TROUGH IS ANALYZED BEHIND THE FRONT EXTENDING 
FROM 31N45W 26N49W TO 25N52W WITH NO ASSOCIATED SHOWER ACTIVITY. 
THE E ATLC IS DOMINATED BY A DEEP LAYERED RIDGE WITH THE SURFACE 
RIDGE ANCHORED BY A 1023 MB HIGH W OF THE CANARY ISLANDS NEAR 
28N25W AND THE UPPER LEVEL RIDGE NEAR 22N26W WHICH IS KEEPING 
CONDITIONS FAIR ACROSS THE AREA. 

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$
WALLACE