Tropical Weather Discussion
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000
AXNT20 KNHC 281158
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST SAT FEB 28 2015

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
1145 UTC.

...SPECIAL FEATURES...

...GALE WARNING FOR THE SW CARIBBEAN...

GALE WARNING IS IN EFFECT FOR COLOMBIA COASTAL WATERS FROM 10.5N
TO 13N BETWEEN 73W AND 77W AND IS FORECAST TO CONTINUE THROUGH
THE AFTERNOON HOURS. GALE WINDS ARE EXPECTED TO RESUME SATURDAY
NIGHT AND CONTINUE THROUGHOUT MONDAY MORNING. PLEASE SEE THE
LATEST HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS
MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE TROPICAL
ATLANTIC NEAR 05N09W SW TO 02S20W WHERE THE ITCZ BEGINS AND
CONTINUES ALONG 03S30W TO THE NORTHERN COAST OF BRAZIL NEAR
02S41W. SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS ARE
WITHIN 200 NM N OF THE MONSOON TROUGH AND FROM 06S TO 02N W OF
20W.

...DISCUSSION...

GULF OF MEXICO...

A BROAD SURFACE RIDGE ANCHORED BY TWO 1041 MB HIGH PRESSURE
CENTERS S OF THE GREAT LAKES COVERS THE CENTRAL AND EASTERN U.S.
AND EXTENDS S ACROSS THE GULF. THIS RIDGE IS PROVIDING
NORTHEASTERLY TO EASTERLY WIND FLOW OF 15 TO 25 KT...HIGHEST ON
THE NORTHERN GULF N OF 25N WHERE THE PRESSURE GRADIENT IS
TIGHTER. A WEAK FRONTAL SYSTEM IS OVER THE W ATLC WATERS BEING
ANALYZED AS A STATIONARY FRONT OVER THE SW N ATLC...ACROSS THE
STRAITS OF FLORIDA...DISSIPATING OVER THE YUCATAN CHANNEL TO W
OF THE NORTHERN YUCATAN PENINSULA NEAR 20N91W. OVER THE FAR
WESTERN GULF...A WEAKNESS IN THE RIDGE IS ANALYZED AS A SURFACE
TROUGH ALONG 27N97W TO 22N97W TO 19N94W. DEEP LAYER MOISTURE
ACROSS THE BASIN ALONG WITH AN UPPER LEVEL DIFFLUENT ENVIRONMENT
SUPPORT BROKEN TO OVERCAST SKIES AND SCATTERED SHOWERS N OF 25N
AND ISOLATED SHOWERS ELSEWHERE. GOES-13 IFR PROBABILITIES DEPICT
MEDIUM TO HIGH CHANCES OF FOG OVER THE EASTERN GULF E OF 85W AND
OVER WESTERN AND CENTRAL FLORIDA S OF 28N...THESE BEING
CONFIRMED BY SURFACE OBSERVATIONS. WITH LITTLE SUPPORT
ALOFT...THE STATIONARY FRONT IS FORECAST TO DISSIPATE LATER THIS
MORNING LEAVING A SURFACE RIDGE AS THE DOMINANT FEATURE FOR THE
NEXT THREE DAYS.

CARIBBEAN SEA...

PATCHES OF SHALLOW MOISTURE CONTINUE TO MOVE ACROSS THE LEEWARD
AND VIRGIN ISLANDS...THE GREATER ANTILLES AND THE NW CARIBBEAN
SEA N OF 18N SUPPORTING CLOUDINESS AND SCATTERED TO ISOLATED
SHOWERS. HOWEVER...NO DEEP CONVECTION IS EXPECTED AS MIDDLE TO
UPPER LEVEL DRY AIR DOMINATES ACROSS THE ENTIRE REGION. TRADES
OF 20 TO 25 KT ARE OVER THE EASTERN AND CENTRAL
BASIN...INCREASING TO NEAR GALE FORCE WINDS ALONG THE COAST OF
COLOMBIA. A GALE WARNING IS IN EFFECT FOR COLOMBIA COASTAL
WATERS. PLEASE SEE THE SPECIAL FEATURES SECTION ABOVE FOR MORE
DETAILS. ELSEWHERE...TRADES OF 10 TO 15 KT DOMINATE. LITTLE
CHANGE IS EXPECTED OVER THE NEXT 3 DAYS.

...HISPANIOLA...

A SHALLOW MOIST AIRMASS CONTINUES TO MOVE ACROSS THE
ISLAND...THUS SUPPORTING CLOUDINESS AND ISOLATED SHOWERS. THIS
CONDITIONS ARE EXPECTED TO CONTINUE THROUGH SATURDAY NIGHT.

ATLANTIC OCEAN...

A WEAK FRONTAL SYSTEM OVER THE W ATLC ANCHORED BY A 1024 MB LOW
N OF THE AREA OF DISCUSSION IS ANALYZED AS A STATIONARY FRONT
FROM 30N69W SW TO THE NORTHERN BAHAMAS NEAR 26N76W TO THE
STRAITS OF FLORIDA NEAR 24N80W TO W OF THE NORTHERN YUCATAN
PENINSULA. DEEP LAYER MOISTURE ALONG WITH UPPER DIVERGENCE
SUPPORT SCATTERED SHOWERS AND ISOLATED TSTMS W OF THE FRONTAL
BOUNDARY. OTHERWISE...THE AZORES HIGH ANCHORED BY A 1037 MB HIGH
NEAR 35N26W COVERS THE REMAINDER BASIN AND SUPPORTS FAIR
WEATHER. WITH LITTLE TO NONE SUPPORT ALOFT...THE FRONT IS
FORECAST TO DISSIPATE OVER THE SW N ATLC SATURDAY
AFTERNOON...LEAVING SURFACE RIDGING AS THE DOMINANT FEATURE
THROUGH LATE SUNDAY.

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

$$
NR



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