Atlantic Tropical Weather Discussion

000
AXNT20 KNHC 251802
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT SAT MAY 25 2013

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...WEATHER OBSERVATIONS...RADAR...AND
METEOROLOGICAL ANALYSIS.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE
IMAGERY THROUGH 1715 UTC.

...THE ITCZ/THE MONSOON TROUGH... 

THE MONSOON TROUGH PASSES THROUGH COASTAL GUNIEA
NEAR 10N14W TO 6N21W. THE ITCZ CONTINUES FROM 6N21W
TO 4N30W AND 2N38W. CONVECTIVE PRECIPITATION...
NUMEROUS STRONG IN THE COASTAL WATERS AND INLAND AREAS
FROM LIBERIA NEAR 5N TO 9N IN SIERRA LEONE AND GUINEA
BETWEEN 9W AND 17W. SCATTERED TO NUMEROUS STRONG TO 
THE SOUTH OF 10N IN THE WATER BETWEEN 53W AND 59W...
REACHING THE COASTS OF SURINAME AND GUYANA. SCATTERED
STRONG IS FROM 4N TO 7N BETWEEN 21W AND 31W...FROM THE
EQUATOR TO 2N BETWEEN 43W AND 44W...FROM 2N TO 3N
BETWEEN 48W AND 49W...FROM 5N TO 7N BETWEEN 44W AND
48W.

...DISCUSSION...

THE GULF OF MEXICO...

A MIDDLE LEVEL TO UPPER LEVEL RIDGE EXTENDS FROM THE
ISTHMUS OF TEHUANTEPEC OF SOUTHERN MEXICO...THROUGH THE
WESTERN GULF OF MEXICO...BEYOND SOUTHWESTERN LOUISIANA.
ANTICYCLONIC WIND FLOW COVERS THE GULF OF MEXICO.
COMPARATIVELY DRIER AIR IN SUBSIDENCE IN WATER VAPOR
IMAGERY COVERS THE GULF OF MEXICO TO THE EAST OF 90W.

A SURFACE RIDGE PASSES THROUGH ALABAMA...INTO THE EAST
CENTRAL GULF OF MEXICO...TO THE YUCATAN PENINSULA OF
MEXICO.

A SURFACE TROUGH IS IN THE SOUTHWESTERN CORNER OF THE
AREA...ALONG 21N96W 18N95W. SCATTERED MODERATE TO
ISOLATED STRONG CONVECTIVE PRECIPITATION IS FROM 19N
TO 21N BETWEEN 95W AND 97W.

BROKEN TO OVERCAST CONVECTIVE DEBRIS CLOUDS FROM 
EARLIER DISSIPATED PRECIPITATION ARE TO THE NORTH OF
22N WITHIN 130 NM OF THE COASTS OF MEXICO AND TEXAS.
SCATTERED TO NUMEROUS STRONG CONVECTIVE PRECIPITATION
IS IN TEXAS FROM 29N TO 30N BETWEEN 96W AND 98W.

LOW CLOUD CEILINGS COVER MORE THAN FIFTY PERCENT OF THE
TEXAS COASTAL PLAINS. FAIR SKIES/CLEAR SKIES AT OR LOWER
THAN 12000 FEET ARE REPORTED FROM LOUISIANA INTO ALABAMA.
NAPLES FLORIDA IS REPORTING A CLOUD CEILING RANGING
FROM 5000 FEET TO 7000 FEET. FORT MYERS FLORIDA IS
REPORTING SCATTERED CLOUDS NEAR 55000 FEET.
MARATHON KEY IS REPORTING SCATTERED CLOUDS NEAR 4000 FEET.
THE NAVAL AIR STATION IN KEY WEST IS REPORTING CLOUD 
CEILINGS RANGING IN HEIGHT FROM 3500 FEET TO 5000 FEET.
FAIR SKIES/CLEAR SKIES AT OR LOWER THAN 12000 FEET ARE
REPORTED ELSEWHERE IN FLORIDA.

FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE
TO THE NORTH OF 27N TO THE WEST OF 88W...

LOW CLOUD CEILINGS ARE BEING REPORTED AT THE ICAO
STATION KHQI. FAIR SKIES/CLEAR SKIES AT OR LOWER THAN
12000 FEET ARE REPORTED ELSEWHERE.

THE CARIBBEAN SEA...                                                

MIDDLE LEVEL TO UPPER LEVEL NORTHWESTERLY WIND FLOW
MOVES INTO THE AREA...THROUGH THE YUCATAN CHANNEL AND
ACROSS THE YUCATAN PENINSULA. THE WIND FLOW BECOMES
MORE WESTERLY AS IT CROSSES 70W.

THE NORTHWESTERLY WIND FLOW ALSO CROSSES PARTS OF
CENTRAL AMERICA...REACHING HONDURAS. THE FLOW CURVES
ANTICYCLONICALLY TOWARD NICARAGUA...PASSING THROUGH
COSTA RICA...INTO THE EASTERN PACIFIC OCEAN.

A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH THE
ATLANTIC OCEAN NEAR 32N71W...TO 27N71W 21N69W...TO 15N65W
IN THE EAST CENTRAL CARIBBEAN SEA. CONVECTIVE PRECIPITATION...
IN THE CARIBBEAN SEA AND THE NEARBY ATLANTIC OCEAN SCATTERED
MODERATE TO STRONG FROM 15N TO 20N BETWEEN 60W AND 67W...AND
FROM 20N TO 22N BETWEEN 67W AND 70W.

24-HOUR RAINFALL TOTALS IN INCHES FOR THE PERIOD
ENDING AT 25/1200 UTC...ACCORDING TO THE PAN AMERICAN
TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN...
ARE 0.51 FOR SAN JUAN PUERTO RICO...0.29 FOR TRINIDAD...
AND 0.17 FOR GUADELOUPE.

THE MONSOON TROUGH IS ALONG 8N74W IN COLOMBIA TO EASTERN PANAMA 
NEAR 8N78W...TO 9N82W IN WESTERN PANAMA...THROUGH 9N83W IN 
SOUTHERN COSTA RICA...BEYOND 9N87W IN THE EASTERN PACIFIC OCEAN. 
CONVECTIVE PRECIPITATION...SCATTERED STRONG IS IN THE 
SOUTHWESTERN CORNER OF THE CARIBBEAN SEA TO THE SOUTH OF 12N 
BETWEEN 78W AND THE COASTAL PLAINS FROM WESTERN PANAMA TO 
NORTHEASTERN NICARAGUA. 

HISPANIOLA...

MIDDLE LEVEL TO UPPER LEVEL NORTHWESTERLY WIND FLOW IS MOVING
ACROSS THE AREA AT THE MOMENT. THE BASE OF A MIDDLE LEVEL TO
UPPER LEVEL TROUGH IS IN THE EAST CENTRAL CARIBBEAN SEA NEAR
15N65W. 

A SURFACE TROUGH IS EXPECTED TO SPAN THE AREA OF HISPANIOLA
FOR THE NEXT FEW DAYS. EXPECT A CHANCE OF RAINSHOWERS OR
THUNDERSTORMS DURING THE NEXT FEW DAYS. THE GFS MODEL FOR
700 MB STARTS WITH THE AREA UNDER THE INFLUENCE OF ANTICYCLONIC
WIND FLOW...AND ULTIMATELY IN THE AREA OF AN INVERTED TROUGH.
THE GFS MODEL FOR 500 MB STARTS WITH HISPANIOLA IN THE AREA
OF A TROUGH FOR AT LEAST THE FIRST NEXT 24 TO 30 HOURS. THE
PATTERN CHANGES TO A RIDGE FOR THE NEXT 24 HOURS OR SO. THE
GFS MODEL FOR 200 MB SHOWS A TROUGH DURING THE NEXT FEW DAYS.

THE ATLANTIC OCEAN...

A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 32N71W
TO 27N71W 21N69W...TO 15N65W IN THE EAST CENTRAL CARIBBEAN SEA.
A COLD FRONT PASSES THROUGH 32N70W TO 28N75W...ALONG THE
NORTHERN BAHAMAS...TO THE SOUTHEASTERN FLORIDA COAST FROM 26N
TO 27N. A PRE-FRONTAL SURFACE TROUGH IS ALONG 31N70W 27N74W.
CONVECTIVE PRECIPITATION...IN THE CARIBBEAN SEA AND THE NEARBY
ATLANTIC OCEAN SCATTERED MODERATE TO STRONG FROM 15N TO 20N
BETWEEN 60W AND 67W...AND FROM 20N TO 22N BETWEEN 67W AND 70W.
IN THE ATLANTIC OCEAN SCATTERED MODERATE TO ISOLATED STRONG
TO THE NORTH OF 25N BETWEEN 65W AND 73W.

A MIDDLE LEVEL TO UPPER LEVEL TROUGH IS ALONG 27N61W
TO 20N57W. RAINSHOWERS ARE POSSIBLE FROM 22N TO 32N
BETWEEN 51W AND 58W.

A MIDDLE LEVEL TO UPPER LEVEL TROUGH EXTENDS FROM A 31N33W
CYCLONIC CIRCULATION CENTER...TO 26N34W AND 18N43W.
A 1022 MB LOW PRESSURE CENTER IS NEAR 29N39W. A SURFACE
TROUGH CURVES AWAY FROM THE LOW CENTER TO 30N38W 28N36W
23N40W 22N44W. CONVECTIVE PRECIPITATION...SCATTERED
MODERATE TO ISOLATED STRONG FROM 29N TO 32N BETWEEN 30W
AND 32W. RAINSHOWERS ARE POSSIBLE FROM 21N TO 28N
BETWEEN 32W AND 46W.

BROAD SURFACE ANTICYCLONIC WIND FLOW COVERS THE ATLANTIC OCEAN
AWAY FROM THE 1022 MB LOW PRESSURE CENTER THAT IS NEAR 29N39W
AND THE ASSOCIATED SURFACE TROUGH.

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...
FOR MORE DETAILS ABOUT THE 20 KNOT WINDS OR LESS AND THE
9 FOOT SEA HEIGHTS...THAT ARE IN AN AREA THAT IS BOUNDED
BY 18N60W 18N56W 11N49W 11N53W 18N60W

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

$$
MT