000
AXNT20 KNHC 060537
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
205 AM EDT WED OCT 06 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 
0515 UTC.

...SPECIAL FEATURE...
A 1003 MB LOW IS N OF PUERTO RICO NEAR 21N67W WITH A SURFACE 
TROUGH EXTENDING S FROM THE LOW THROUGH THE MONA PASSAGE INTO 
THE CARIBBEAN THEN SW TO COSTA RICA. SCATTERED MODERATE/STRONG 
CONVECTION COVERS A LARGE AREA MOSTLY E OF THE LOW/TROUGH FROM 
14N-20N BETWEEN 60W-67W...WITHIN 90 NM OF LINE FROM 20N64W TO TO 
25N67W...AND WITHIN1 20 NM ALONG THE COAST OF HISPANIOLA W OF 
THE SURFACE TROUGH TO 73W. THE LOW HAS A DISTINCT DRY SLOT W AND 
S OF THE LOW AS SEEN IN BOTH INFRARED AND WATER VAPOR SATELLITE 
IMAGERY. AN UPPER LOW IS NW OF THE SURFACE LOW ENHANCING THE 
ACTIVITY. THIS SYSTEM HAS BECOME BETTER ORGANIZED DURING THE 
PAST FEW HOURS. ONLY A SMALL INCREASE IN THE ORGANIZATION OF 
THIS SYSTEM WOULD RESULT IN THE FORMATION OF A SUBTROPICAL OR 
TROPICAL CYCLONE LATER TODAY. THERE IS A HIGH CHANCE OF THIS 
SYSTEM BECOMING A SUBTROPICAL OR TROPICAL CYCLONE DURING THE 
NEXT 48 HOURS AS IT MOVES NW NEAR 10 KT. LOCALLY HEAVY RAINS AND 
GUSTY WINDS WILL LIKELY CONTINUE OVER THE LEEWARD ISLANDS...THE 
VIRGIN ISLANDS...AND PUERTO RICO DURING THE NEXT DAY OR TWO.

...TROPICAL WAVES...

THE TROPICAL WAVE THAT WAS ALONG 41W WAS RELOCATED EAST TO WHERE 
A SURFACE TROUGH/LOW WAS PREVIOUSLY ANALYZED ALONG 33W/34W WITH 
A 1012 MB LOW NEAR 7N. HOWEVER ON THE 0300 UTC SATELLITE IMAGERY 
THE SURFACE TROUGH...NOW TROPICAL WAVE APPEARS TO BE LOSING ITS 
IDENTITY LEAVING BEHIND A SMALL LOW LEVEL SWIRL. 

...ITCZ...

THE ITCZ AXIS IS ANALYZED ALONG 16N16W 8N28W 8N38W 5N45W 5N53W. 
SCATTERED MODERATE/STRONG CONVECTION IS INLAND AND WITHIN 90 NM 
ALONG THE COAST OF AFRICA BETWEEN 7N-11N. CLUSTERS OF SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 60 NM OF LINE FROM 
4N36W TO 10N40W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE 
FROM 3N-6N BETWEEN 20W-25W. 

...DISCUSSION...

GULF OF MEXICO...
THE GULF REMAINS UNDER CLEAR SKIES AGAIN TONIGHT WITH BROKEN TO 
OVERCAST LOW CLOUDS AND POSSIBLE ISOLATED SHOWERS REMAINING 
ACROSS THE SW GULF S OF A LINE FROM N OF TAMPICO TO CUIDAD DEL 
CARMEN. AN UPPER TROUGH OVER THE E U.S. COVERS THE N GULF WHILE 
AN UPPER RIDGE FROM THE CARIBBEAN COVERS THE S GULF GIVING THE 
ENTIRE GULF WATERS SW TO W UPPER FLOW. HIGH PRESSURE REMAINS IN 
FIRM CONTROL OF THE GULF ANCHORED OVER SE MISSOURI BY A 1028 MB 
HIGH. 

CARIBBEAN SEA...
A SURFACE TROUGH ENTERS THE CARIBBEAN FROM THE LOW DISCUSSED IN 
THE SPECIAL FEATURES THROUGH THE MONA PASSAGE ALONG 15N72W TO 
OFF THE COAST OF COSTA RICA NEAR 11N83W. BROAD UPPER RIDGE 
COVERS THE CARIBBEAN WITH THE AXIS EXTENDING FROM HISPANIOLA SW 
TO PANAMA PROVIDING DIFFLUENCE ALOFT TO ENHANCE THE ACTIVITY 
OVER THE E CARIBBEAN TO ACROSS THE LESSER ANTILLES AS DISCUSSED 
IN THE SPECIAL FEATURES. SCATTERED SHOWERS AND POSSIBLE ISOLATED 
THUNDERSTORMS ARE ACROSS THE ENTIRE S CARIBBEAN S OF 14N TO 
INLAND OVER PORTION OS SOUTH AND CENTRAL AMERICA. MODERATELY DRY 
AIR ALOFT IS OVER THE NW CARIBBEAN WITH SCATTERED AREAS OF LOW 
LEVEL CLOUDS W OF A LINE FROM CUBA NEAR 20N78W TO THE TIP OF 
HONDURAS/NICARAGUA. 

ATLANTIC OCEAN...
THE PRIMARY CONCERN TONIGHT IS THE 1003 MB LOW IN THE SPECIAL 
FEATURES ABOVE. THE DEEP LAYERED TROUGH THAT COVERS THE E U.S. 
AND THE N GULF OF MEXICO EXTENDS INTO THE W ATLC TO 76W AND 
CONTINUES TO SUPPORT A STATIONARY FRONT THAT ENTERS THE W ATLC 
NEAR 32N72W S ALONG 29N73W ACROSS THE BAHAMA ISLANDS TO 23N78W. 
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 180 NM E OF 
THE FRONT S OF 27N AND WITHIN 120 NM W OF THE FRONT S OF 28N. 
ISOLATED SHOWERS ARE POSSIBLE WITHIN 90 NM E AND 150 NM W OF THE 
REMAINDER OF THE FRONT. AN UPPER LOW IS N OF PUERTO RICO NEAR 
22N69W WITH A SHORTWAVE UPPER TROUGH EXTENDING SE TO 19N67W 
ENHANCING THE ACTIVITY ASSOCIATED WITH THE LOW IN THE SPECIAL 
FEATURES. A SECOND LARGE CUT OFF UPPER LOW IS CENTERED IN THE 
CENTRAL ATLC NEAR 21N53W BECOMING ELONGATED FROM SE TO NW AND  
ENHANCING CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG 
CONVECTION WITHIN 300 NM E OF A SURFACE TROUGH THAT EXTENDS 
ALONG 50W FROM 11N-20N WHILE THE UPPER LOW IS SUPPORTING A 1012 
MB SURFACE LOW NEAR 20N53W. A SURFACE RIDGE EXTENDS OVER THE E 
ATLC FROM A 1025 MB HIGH JUST N OF THE DISCUSSION AREA NEAR 
33N46W SE TO 21N26W. 

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

$$
LANDSEA