[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 291802
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST SUN DEC 29 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.

...SPECIAL FEATURES...
A COLD FRONT CURRENTLY ANALYZED ACROSS THE SOUTHERN U.S. PLAINS
IS EXPECTED TO EMERGE INTO THE WESTERN GULF OF MEXICO WATERS
MONDAY BRINGING WITH IT GALE FORCE N-NE WINDS FROM 22N-24N W OF
95W BY 31/0000 UTC. SEE LATEST NWS HIGH SEAS FORECAST UNDER
AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 07N12W TO
05N17W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM
05N17W TO 05N21W TO 05N30W TO 03N40W TO THE EQUATOR NEAR 45W.
SCATTERED MODERATE CONVECTION IS FROM 04N-06N BETWEEN 24W-34W.

...DISCUSSION...

GULF OF MEXICO...
A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR
IMAGERY OVER THE TENNESSEE AND OHIO RIVER VALLEYS THIS AFTERNOON
THAT SUPPORTS A COLD FRONT ANALYZED INTO THE NE GULF NEAR
APALACHEE BAY EXTENDING S-SW TO THE NW TIP OF THE YUCATAN
PENINSULA NEAR 21N90W TO 20N92W. ISOLATED SHOWERS AND TSTMS ARE
OCCURRING WITHIN 90 NM EAST OF THE FRONT. A PRE-FRONTAL SURFACE
TROUGH IS ANALYZED FROM THE YUCATAN CHANNEL NEAR 22N86W N-NE TO
26N84W AND IS PROVIDING THE MAIN FOCUS FOR SCATTERED SHOWERS AND
TSTMS OCCURRING PRIMARILY NORTH AND EAST OF THE BOUNDARY. THE
AREA OF CONVECTION COVERS THE FAR EASTERN GULF AND PORTIONS OF
THE FLORIDA PENINSULA FROM 23N-29N BETWEEN 80W-85W.
OTHERWISE...A WEAK SURFACE TROUGH IS NOTED ACROSS THE SW GULF
FROM 20N95W NW TO 24N97W THAT BRIDGES TWO SURFACE RIDGES...ONE
ANCHORED BY A 1017 MB HIGH CENTERED NEAR 27N96W AND THE OTHER
ANCHORED BY A 1019 MB HIGH CENTERED ACROSS INLAND MEXICO NEAR
20N97W. POSSIBLE ISOLATED SHOWERS ARE OCCURRING WITHIN 60 NM
EITHER SIDE OF THE SURFACE TROUGH AXIS. THE COLD FRONT IS
FORECAST TO SWEEP EAST OF THE BASIN BY EARLY MONDAY WITH N-NE
WINDS PERSISTING IN THE RANGE OF 10 TO 20 KT. THE PRESSURE
GRADIENT IS EXPECTED TO STRENGTHEN ACROSS THE WESTERN GULF LATE
MONDAY AND SPREAD STRONGER N-NE WINDS EASTWARD THROUGH WEDNESDAY
IN ASSOCIATION WITH THE NEXT COLD FRONT TO EMERGE OFF THE TEXAS
AND LOUISIANA COAST BY MID-DAY MONDAY.

CARIBBEAN SEA...
THE CARIBBEAN IS UNDER THE INFLUENCE OF SOUTHWEST TO WESTERLY
FLOW ALOFT. WATER VAPOR IMAGERY INDICATES THE AIRMASS TO BE VERY
DRY AND STABLE WITH CONFLUENCE ALOFT MAXIMIZED OVER THE EASTERN
CARIBBEAN E OF 70W. AT THE SURFACE...THE MAIN FEATURE IS A PRE-
FRONTAL SURFACE TROUGH ANALYZED FROM THE SE GULF OF MEXICO
THROUGH THE YUCATAN CHANNEL TO THE COAST OF EASTERN HONDURAS
NEAR 16N85W. ISOLATED SHOWERS AND TSTMS ARE OCCURRING IN THE
VICINITY OF THE YUCATAN CHANNEL REGION WITH ISOLATED SHOWERS
OCCURRING ELSEWHERE S OF 21 W OF 84W...INCLUDING THE GULF OF
HONDURAS AND INLAND PORTIONS OF CENTRAL AMERICA. OTHERWISE...
TRADES PERSIST IN THE RANGE OF 15 TO 25 ELSEWHERE S OF 19N WITH
THE STRONGEST SPEEDS NOTED ON RECENT SCATTEROMETER DATA BETWEEN
70W-80W AND IN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. 25 TO
30 KT NE TO E WINDS WERE DEPICTED ON THE MOST RECENT 29/1412 UTC
ASCAT PASS S OF 13N BETWEEN 72W-78W. ISOLATED LOW-TOPPED SHOWERS
ARE EXPECTED TO CONTINUE RIDING WESTWARD ON THE TRADES THIS
AFTERNOON INTO THE EVENING AND OVERNIGHT PERIOD.

...HISPANIOLA...
CURRENTLY ONLY A FEW PASSING TRADEWIND LOW-TOPPED SHOWERS ARE
IMPACTING THE EASTERN HALF OF THE ISLAND THIS AFTERNOON WITH
PLENTY MORE ISOLATED SHOWER ACTIVITY TO THE EAST AS NOTED ON
SATELLITE IMAGERY AND SAN JUAN PUERTO RICO DOPPLER RADAR
IMAGERY. THE QUICK PASSING SHOWERS SHOULD CONTINUE THROUGH THE
NEXT 24 TO 36 HOURS WITH NO SIGNIFICANT DEEP CONVECTION EXPECTED
DUE TO DRY AND VERY STABLE NORTHWESTERLY WINDS ALOFT.

ATLANTIC OCEAN...
A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS MOVING OVER THE
TENNESSEE AND OHIO RIVER VALLEYS THIS AFTERNOON SUPPORTING A
1009 MB LOW CENTERED OVER THE CAROLINAS. THE ASSOCIATED COLD
FRONT REMAINS ANALYZED IN THE GULF OF MEXICO HOWEVER MIDDLE TO
UPPER LEVEL DIFFLUENCE AND LOW-LEVEL MOISTURE CONVERGENCE
CONTINUES TO BE MAXIMIZED WITHIN THE WARM SECTOR OF THIS SYSTEM
GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS N OF 23N W OF
76W. THE REMAINDER OF THE SW NORTH ATLC IS UNDER THE INFLUENCE
OF A SURFACE RIDGE ANCHORED BY A 1028 MB HIGH CENTERED NE OF
BERMUDA NEAR 34N59W. A FEW PASSING ISOLATED TRADEWIND SHOWERS
ARE NOTED ON SATELLITE IMAGERY ON THE SOUTHERN PERIPHERY OF THE
RIDGE S OF 22N BETWEEN 55W-73W. OVER THE CENTRAL ATLC...AN UPPER
LEVEL TROUGH AXIS EXTENDS FROM 36N46W SW TO A BASE NEAR 24N56W.
THE TROUGHING ALOFT SUPPORTS A COLD FRONT ANALYZED INTO THE
DISCUSSION AREA NEAR 32N39W SW TO 25N56W. WIDELY SCATTERED
SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 90 NM EITHER
SIDE OF THE FRONT. FINALLY...THE EASTERN ATLC IS INFLUENCE BY A
SURFACE RIDGE ANCHORED BY A 1034 MB HIGH CENTERED SW OF THE
IBERIAN PENINSULA NEAR 36N13W. STRONG NORTHEASTERLY WINDS WERE
DEPICTED IN THE VICINITY OF THE CANARY ISLANDS ON AN EARLIER
MORNING ASCAT PASS N OF 23N E OF 21W DUE TO A STRONG PRESSURE
GRADIENT ASSOCIATED WITH THE AFOREMENTIONED 1034 MB HIGH AND A
SURFACE TROUGH ANALYZED ACROSS INLAND NW AFRICA FROM 25N07W TO
31N11W.

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

$$
HUFFMAN

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