[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 270002
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT WED MAR 26 2014

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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2345 UTC.

...SPECIAL FEATURES...
A COLD FRONT ENTER THE SW NORTH ATLC REGION THROUGH 32N60W TO
THE SE BAHAMAS NEAR 22N75W WITH GALE FORCE W TO NW WINDS N OF
27N WEST OF THE FRONT TO 74W AND GALE FORCE S TO SW WINDS N OF
29N EAST OF THE FRONT TO 58W. WINDS ARE FORECAST TO DROP BELOW
GALE FORCE TONIGHT. SEE NWS HIGH SEAS FORECAST UNDER AWIPS/WMO
HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS.

A STRONG PRESSURE GRADIENT IS EXPECTED TO SETUP ACROSS THE SW
CARIBBEAN SEA BETWEEN STRONG HIGH PRESSURE CENTERED ACROSS THE
SE CONUS AND LOWER PRESSURE ACROSS THE NORTHWESTERN SOUTH
AMERICAN CONTINENT. GALE FORCE NE TO E WINDS ARE ANTICIPATED TO
COMMENCE BY 27/0600 UTC. SEE LATEST NWS HIGH SEAS FORECAST UNDER
AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS.

A STRONG PRESSURE GRADIENT EXISTS BETWEEN HIGH PRESSURE ACROSS
THE EASTERN ATLC AND LOWER PRESSURE CENTERED ACROSS INLAND
NORTHWEST AFRICA THIS AFTERNOON. GALE FORCE N TO NE WINDS ARE
OCCURRING FROM 29N-32N BETWEEN 10W-13W ALONG THE COAST OF
MOROCCO. SEE LATEST METEO-FRANCE HIGH SEAS FORECAST UNDER WMO
HEADER FQNT50 LFPW.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 08N13W TO
01N21W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM
01N21W TO THE EQUATOR NEAR 25W. SCATTERED MODERATE CONVECTION IS
FROM 01N-04N BETWEEN 18W-25W.

...DISCUSSION...

GULF OF MEXICO...
FLAT BROAD MIDDLE TO UPPER LEVEL RIDGING IS NOTED ON WATER VAPOR
IMAGERY OVER THE GULF BASIN THIS EVENING AS THE VERY DEEP UPPER
LEVEL TROUGH LIFTS OUT TO THE NE OVER THE N ATLC. A MID-LEVEL
SHORTWAVE TROUGH IS EMBEDDED WITHIN THE FLAT RIDGE WITH AXIS
ALONG 93W N OF 28N. THIS ENERGY ALOFT IS GENERATING EXTENSIVE
CLOUDINESS AND AN AREA OF SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS ACROSS THE NW GULF EXTENDING NWD ALONG THE UPPER
TEXAS AND LOUISIANA COASTS. THIS ACTIVITY CONTINUES TO MOVE EAST
AT 20-25 KT. THIS WAS CONFIRMED BY MOSAIC DOPPLER RADAR IMAGERY
AND LIGHTNING DATA. OVERCAST LOW AND MID LEVEL CLOUDS WITH
EMBEDDED SHOWERS WERE NOTED ELSEWHERE N OF 21N W OF 88W...TO THE
E OF A SURFACE TROUGH EXTENDING FROM 23N95W TO 19N94W. THIS AREA
OF CONVECTION LIES WITHIN THE SOUTHWESTERN PERIPHERY OF A
SURFACE RIDGE ANCHORED BY A 1029 MB HIGH CENTERED OVER ALABAMA.
WITH THE RIDGE IN PLACE AND EXPECTED TO SLIDE EASTWARD OVER THE
NEXT 24 HOURS...E-SE WINDS WILL PREVAIL IN THE RANGE OF 15 TO 25
KT WITH THE STRONGER WINDS LOCATED GENERALLY OVER WESTERN
PORTIONS...W OF 90W...THROUGH EARLY THURSDAY...AND THEN SHIFT TO
PORTIONS OF THE EASTERN GULF THEREAFTER THROUGH FRIDAY. TEMPERED
SOUTHERLY FLOW IS FORECAST FOR FRIDAY IN ADVANCE OF THE NEXT
COLD FRONT TO EMERGE OFF THE TEXAS AND LOUISIANA COAST EARLY
SATURDAY.

CARIBBEAN SEA...
NEARLY ZONAL WESTERLY FLOW ALOFT DOMINATED THE CARIBBEAN BASIN
THIS EVENING...HOWEVER THE SOUTHERLY EXTENT OF A MIDDLE TO UPPER
LEVEL TROUGH DIPS SOUTHWARD TO A BROAD BASE OVER THE SW NORTH
ATLC. THIS TROUGH WAS SUPPORTING A SURFACE COLD FRONT FROM THE
SE BAHAMAS NEAR 22N75W TO 21N78W AND OVER CUBA. THE FRONT BECAME
STATIONARY FROM THE COAST OF CUBA TO NEAR COZUMEL YUCATAN.
DURING THE PAST FEW HOURS WEAKENING CONTINUES TO TAKE PLACE AND
THE FRONT IS EXPECTED TO BECOME DIFFUSE TONIGHT. THE FRONT
REMAINS RELATIVELY PRECIPITATION-FREE THIS EVENING WITH THE MOST
SIGNIFICANT IMPACTS BEING SLIGHTLY COOLER TEMPERATURES AND DRIER
AIR ALONG WITH STRONGER NE WINDS NORTH OF THE FRONT.
OTHERWISE...THE REMAINDER OF THE BASIN IS EXPERIENCING TRADE
WINDS IN THE RANGE OF 10 TO 20 KT WITH THE USUAL SLIGHTLY
STRONGER...20 TO 25 KT WINDS EXPECTED IN CLOSE PROXIMITY TO THE
COAST OF COLOMBIA. THESE WINDS ARE FORECAST TO INCREASE TO GALE
FORCE FROM 11N TO 13N BETWEEN 74W AND 77W LATER TONIGHT. SKIES
WILL REMAIN FAIR THROUGH THE OVERNIGHT HOURS.

...HISPANIOLA...
SCATTERED TO BROKEN CLOUDS ARE INDICATED OVER HISPANIOLA WITH
ISOLATED THUNDERSTORMS OVER THE INTERIOR. THE PROXIMITY OF A PRE-
FRONTAL TROUGH OVER THE NW PORTION OF THE ISLAND WHICH EXTENDED
NE OVER THE SW N ATLC HAS PROVIDED ENOUGH LIFT AND INSTABILITY
TO TRIGGER THIS ACTIVITY.

ATLANTIC OCEAN...
A VIGOROUS AND NEGATIVELY-TILTED UPPER LEVEL TROUGH AND THE
ASSOCIATED DEEP LAYERED CYCLONE IS NOTED ON WATER VAPOR IMAGERY
CENTERED JUST S OF NOVA SCOTIA. THIS TROUGH SUPPORTS A STRONG
COLD FRONT SWEEPING ACROSS THE SW NORTH ATLC THIS EVENING. THE
FRONT EXTENDED FROM 32N60W THROUGH THE SE BAHAMAS TO THE COAST OF
CUBA NEAR 21N77W. A PRE-FRONTAL TROUGH EXTENDED FROM 28N62W TO
THE N COAST OF HISPANIOLA. MOST OF THE SCATTERED SHOWERS AND
ISOLATED TSTMS ARE OCCURRING ALONG AND WITHIN 180-240 NM EAST OF
THE PRE-FRONTAL TROUGH N OF 25N AND WITHIN 60-90 NM E OF THE
TROUGH S OF 25N. THE STRONGEST ACTIVITY WAS CONFINED TO THE
SOUTHERN EXTENT OF THE TROUGH. FARTHER EAST...A SHARP UPPER
LEVEL RIDGE EXTENDED THROUGH 32N45W TO A BASE NEAR 20N55W.
A DOWNSTREAM TROUGH WITH AXIS ALONG 32N14W 22N38W TO A BASE NEAR
15N54W. AT THE SURFACE...THE REMAINDER OF THE CENTRAL AND
EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED
BY A 1033 MB HIGH CENTERED SOUTHEAST OF THE AZORES NEAR 37N24W.

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

$$
COBB


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