[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 111125
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT FRI OCT 11 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1015 UTC.

...SPECIAL FEATURES...

A 1008 MB LOW PRESSURE CENTER IS NEAR 11N35W. CONVECTIVE
PRECIPITATION...NUMEROUS STRONG FROM 10N TO 12N BETWEEN 34W AND
41W. SCATTERED STRONG ELSEWHERE FROM 10N TO 14N BETWEEN 33W AND
44W. UPPER LEVEL WINDS ARE BECOMING LESS CONDUCIVE FOR TROPICAL
CYCLONE FORMATION. SOME DEVELOPMENT OF THIS SYSTEM STILL IS
POSSIBLE DURING THE NEXT DAY OR SO...BEFORE UPPER LEVEL WINDS
BECOME EVEN LESS CONDUCIVE DURING THIS WEEKEND. THIS SYSTEM HAS
A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT
48 HOURS. THE SYSTEM IS FORECAST TO MOVE WESTWARD TO WEST-
NORTHWESTWARD ABOUT 10 KNOTS.

...TROPICAL WAVES...

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 54W/55W TO THE SOUTH OF
20N MOVING WESTWARD 10 TO 15 KNOTS. CONVECTIVE PRECIPITATION...
WIDELY SCATTERED TO SCATTERED MODERATE TO ISOLATED STRONG FROM
16N TO 23N BETWEEN 49W AND 57W.

A CARIBBEAN SEA TROPICAL WAVE IS ALONG 79W/80W TO THE SOUTH OF
18N MOVING WESTWARD 10 KNOTS. A MIDDLE LEVEL TO UPPER LEVEL
TROUGH PASSES THROUGH THE WESTERN ATLANTIC OCEAN NEAR 32N67W...
ACROSS HISPANIOLA...INTO THE SOUTHWESTERN CORNER OF THE
CARIBBEAN SEA. THE TROUGH HAS BEEN WEAKENING IN ITS SATELLITE
IMAGERY REPRESENTATION AS COMPARED TO THE IMAGERY OF 24 HOURS
AGO. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED
STRONG IN THE ATLANTIC OCEAN TO THE NORTH OF 20N BETWEEN 60W AND
75W. ISOLATED MODERATE IN THE CARIBBEAN SEA FROM 17N TO 20N
BETWEEN 65W AND THE WINDWARD PASSAGE. ISOLATED MODERATE
CONVECTIVE PRECIPITATION COVERS THE REST OF THE CARIBBEAN SEA TO
THE SOUTH OF 17N TO THE EAST OF 70W.

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

THE MONSOON TROUGH PASSES THROUGH COASTAL GUINEA NEAR 11N15W...
TO 5N20W 7N28W...TO THE 1008 MB LOW PRESSURE CENTER THAT IS NEAR
11N35W...TO 9N40W AND 8N45W. THE ITCZ CONTINUES FROM 8N45W TO
9N50W. CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM 10N TO
12N BETWEEN 14W AND 16W...AND WITHIN A 30 NM RADIUS OF 10N18W.
SCATTERED MODERATE TO ISOLATED STRONG FROM 1N TO 11N BETWEEN 20W
AND 30W. WIDELY SCATTERED MODERATE TO ISOLATED STRONG FROM 6N
TO 10N BETWEEN 30W AND 40W.

...DISCUSSION...

FROM THE U.S.A. EAST COAST...ACROSS FLORIDA...INTO THE FLORIDA
STRAITS...WESTERN CUBA...ACROSS THE YUCATAN PENINSULA...INTO THE
SOUTHWESTERN CORNER OF THE GULF OF MEXICO...AND THE REST OF THE
GULF OF MEXICO...

A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH FLORIDA AND
THE ADJACENT ATLANTIC OCEAN COASTAL WATERS OF FLORIDA...ACROSS
WESTERN CUBA...INTO THE NORTHWESTERN CORNER OF THE CARIBBEAN
SEA...EVENTUALLY TO 13N81W IN THE WESTERN CARIBBEAN SEA.
COMPARATIVELY DRIER AIR IN SUBSIDENCE...AS SEEN IN WATER VAPOR
IMAGERY...COVERS THE GULF OF MEXICO...EXCEPT FOR THE WEAK
PRECIPITATION THAT IS IN THE SOUTHWESTERN CORNER OF THE GULF OF
MEXICO...TO THE SOUTH OF 24N TO THE WEST OF 90W. A SURFACE RIDGE
PASSES THROUGH THE WESTERN FLORIDA PANHANDLE TO 28N87W THROUGH
THE YUCATAN CHANNEL...INTO THE NORTHWESTERN CORNER OF THE
CARIBBEAN SEA. THE TROUGH SUPPORTS A COLD FRONT THAT PASSES
THROUGH 32N70W TO 29N71W AND 26N74W. THE REST OF THE BOUNDARY IS
DISSIPATING ALONG 26N74W...ALONG THE SOUTHERN BORDER OF ANDROS
ISLAND IN THE BAHAMAS...TO WESTERN CUBA NEAR 22N81W. CONVECTIVE
PRECIPITATION...WIDELY SCATTERED MODERATE TO ISOLATED STRONG
WITHIN 60 NM TO 120 NM ON EITHER SIDE OF 27N75W 19N78W 13N83W.

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 FOLLOWING ICAO
STATIONS...KVAF...KHQI...KGUL...KEHK...AND KGBK. FAIR SKIES/
CLEAR SKIES AT OR LOWER THAN 12000 FEET ARE BEING REPORTED
ELSEWHERE ACROSS THE AREA.

SCATTERED TO BROKEN LOW CLOUDS COVER THE COASTAL PLAINS OF TEXAS
FROM THE MIDDLE TEXAS COAST SOUTHWARD. VISIBILITIES OF 3 MILES
OR LESS AND FOG COVER COASTAL SECTIONS OF LOUISIANA...INCLUDING
ALONG THE NORTHERN SIDE OF LAKE PONTCHARTRAIN...IN SOUTHEASTERN
MISSISSIPPI...AND COASTAL ALABAMA...IN FLORIDA IN CRESTVIEW AND
AT THE NAVAL AIR STATION WHITING FIELD...AND IN BROOKSVILLE.

FROM THE WESTERN ATLANTIC OCEAN INTO THE CARIBBEAN SEA...
INCLUDING ACROSS HISPANIOLA...

A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH THE WESTERN
ATLANTIC OCEAN NEAR 32N67W...ACROSS HISPANIOLA...INTO THE
SOUTHWESTERN CORNER OF THE CARIBBEAN SEA. THE TROUGH HAS BEEN
WEAKENING IN ITS SATELLITE IMAGERY REPRESENTATION AS COMPARED TO
THE IMAGERY OF 24 HOURS AGO. CONVECTIVE PRECIPITATION...WIDELY
SCATTERED MODERATE TO ISOLATED STRONG IN THE COASTAL WATERS OF
HISPANIOLA AND PUERTO RICO. SCATTERED MODERATE TO ISOLATED
STRONG IN THE ATLANTIC OCEAN FROM 20N NORTHWARD BETWEEN 59W AND
76W. WIDELY SCATTERED MODERATE IN THE CARIBBEAN SEA ELSEWHERE
BETWEEN 60W AND 73W. ISOLATED MODERATE IN THE CARIBBEAN SEA FROM
17N TO 20N BETWEEN 65W AND THE WINDWARD PASSAGE.

THE GFS FORECAST FOR 700 MB SHOWS THAT AN INVERTED TROUGH WILL
SPAN THE ISLAND FOR THE FIRST 12 HOURS OF THE FORECAST
PERIOD...AND FOR THE LAST 18 HOURS OF THE FORECAST PERIOD.
ANTICYCLONIC WIND FLOW WITH A RIDGE WILL COVER HISPANIOLA FOR
THE REST OF THE TIME. THE GFS FORECAST FOR 500 MB STARTS WITH
HISPANIOLA BEING IN THE MIDDLE OF A RIDGE THAT IS TO THE NORTH
OF THE AREA AND AN INVERTED TROUGH THAT IS TO THE SOUTH OF THE
AREA. ANTICYCLONIC WIND FLOW WITH A RIDGE EVENTUALLY RETURNS AND
LASTS FOR THE REST OF THE 48 HOUR FORECAST PERIOD. THE GFS
FORECAST FOR 250 MB SHOWS THAT A NORTHEAST-TO-SOUTHWEST ORIENTED
TROUGH WILL CUT ACROSS THE AREA FOR THE FIRST 24 HOURS OF THE
FORECAST PERIOD. HISPANIOLA WILL BE ON THE EASTERN SIDE OF A
DIFFERENT TROUGH FOR THE NEXT 24 HOURS AFTER THAT. THE TROUGH IS
FORECAST TO MOVE FROM 80W EASTWARD.

THE REST OF THE CARIBBEAN SEA...

THE MONSOON TROUGH IS ALONG 9N74W IN COLOMBIA...TO 9N80W IN
PANAMA...BEYOND 9N84W IN SOUTHERN COSTA RICA...INTO THE EASTERN
PACIFIC OCEAN. CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM
6N IN COLOMBIA TO 11N IN THE SOUTHWESTERN CORNER OF THE
CARIBBEAN SEA BETWEEN 73W AND 79W...AND ALONG THE EASTERN SHORES
OF LAKE MARACAIBO IN NORTHWESTERN VENEZUELA.

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...AND THE
OFFSHORE FORECAST...MIAOFFNT3...FOR MORE DETAILS ABOUT THE EAST
WINDS 20 TO 25 KNOTS AND SEA HEIGHTS TO 8 FEET FROM 12N TO 14N
BETWEEN 68W AND 74W.

THE REST OF THE ATLANTIC OCEAN...

A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 32N32W TO
27N34W TO 23N41W...TO A CUT-OFF CYCLONIC CIRCULATION CENTER THAT
IS NEAR 19N47W...TO A SECOND CUT-OFF CYCLONIC CIRCULATION CENTER
THAT IS NEAR 19N55W. THE 19N55W CYCLONIC CENTER IS NEAR THE
54W/55W TROPICAL WAVE. THE TROUGH WAS SUPPORTING A FRONTAL
BOUNDARY SIX HOURS AGO. THE FRONTAL BOUNDARY HAS WEAKENED AND
DISSIPATED. A REMNANT CLOUD LINE...WITH ISOLATED MODERATE
CONVECTIVE PRECIPITATION...IS WITHIN 30 NM TO 60 NM ON EITHER
SIDE OF THE LINE THAT PASSES THROUGH 32N23W 27N27W 25N33W
25N43W. OTHER CLOUDS AND POSSIBLE PRECIPITATION ARE TO THE NORTH
OF 25N BETWEEN 40W AND 50W.

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...FOR MORE
DETAILS ABOUT A 1008 MB LOW PRESSURE CENTER...A POSSIBLE
TROPICAL CYCLONE...NEAR 11N35W. EXPECT NORTHEAST WINDS 20 TO 25
KNOTS AND SEA HEIGHTS FROM 8 TO 11 FEET FROM 11N TO 18N TO THE
EAST OF 41W.

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

$$
MT


This weather bulletin was brought to you by:
www.nashvilleweather.net