[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 281122
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST MON DEC 28 2009

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1115 UTC.

...THE ITCZ...
THE ITCZ AXIS IS CENTERED ALONG 9N13W 3N30W EQ50W. WIDELY
SCATTERED MODERATE CONVECTION IS ALONG THE COAST OF BRAZIL FROM
1N-4N BETWEEN 43W-51W. SCATTERED SHOWERS ARE WITHIN 60 NM OF THE
AXIS BETWEEN 20W-43W.

...DISCUSSION...

THE GULF OF MEXICO...
A WEAK 1016 MB LOW IS CENTERED OVER THE CENTRAL GULF OF MEXICO
NEAR 25N88W. A SURFACE TROUGH EXTENDS S FROM THE LOW TO THE
YUCATAN PENINSULA NEAR 21N88W. PATCHES OF BROKEN LOW CLOUDS DOTS
THE GULF OF MEXICO ESPECIALLY S OF 26N. ELSEWHERE...A SURFACE
TROUGH IS OVER THE W GULF FROM 24N96W TO THE BAY OF CAMPECHE
NEAR 18N95W. OVERCAST LOW CLOUDS ARE S OF 27N AND W OF 93W. IN
THE UPPER LEVELS...A TROUGH WITH AXIS ALONG 98W IS PRODUCING SW
FLOW OVER THE GULF. UPPER LEVEL MOISTURE WITH BROKEN HIGH CLOUDS
ARE OVER TEXAS...THE N GULF N OF 27N...AND N FLORIDA. STRONG
SUBSIDENCE IS OVER THE REMAINDER OF THE GULF. 70-90 KT 25O MB
WINDS ARE NOTED OVER THE N GULF N OF 22N. EXPECT IN 24 HOURS...
FOR THE SURFACE LOW TO MOVE TO S FLORIDA AND DISSIPATE. ALSO
EXPECT THE SURFACE TROUGH OVER THE W GULF TO REMAIN STATIONARY
WITH SHOWERS HEAVIEST OVER THE BAY OF CAMPECHE. 20 KT NORTHERLY
SURFACE FLOW WILL THEN DOMINATE THE REMAINDER OF THE GULF WITH A
GOOD AMOUNT OF COLD AIR ADVECTION.

THE CARIBBEAN SEA...
A 1015 MB LOW IS CENTERED OVER THE YUCATAN CHANNEL NEAR 22N85W.
A SURFACE TROUGH EXTENDS S FROM THE LOW TO HONDURAS NEAR 16N86W.
BROKEN LOW CLOUDS WITH ISOLATED SHOWERS ARE OVER THE NW
CARIBBEAN FROM 18N-23N BETWEEN 83W-87W. FURTHER E... A BAND OF
SHOWERS IS W OF JAMAICA FROM 8N-20N BETWEEN 79W-83W. FURTHER
S...SCATTERED MODERATE CONVECTION IS OVER THE COAST OF N
COLOMBIA FROM 8N-10N BETWEEN 76W-78W. ELSEWHERE...SCATTERED
SHOWERS ARE OVER THE LEEWARD ISLANDS AND PUERTO RICO N OF 17N
BETWEEN 60W-67W. MODERATE TRADEWINDS ARE NOTED OVER THE MAJORITY
OF THE CARIBBEAN AND CENTRAL AMERICA EXCEPT ALONG THE COAST OF N
COLOMBIA WHERE STRONG TRADEWINDS ARE NOTED. IN THE UPPER
LEVELS...AN UPPER LEVEL RIDGE IS CENTERED OVER THE CARIBBEAN
WITH AXIS ALONG 75W. STRONG SUBSIDENCE IS OVER THE ENTIRE
CARIBBEAN AND CENTRAL AMERICA EXCEPT OVER PANAMA AND COSTA RICA
WHERE BROKEN HIGH CLOUDS ARE NOTED. EXPECT OVER THE NEXT 24
HOURS FOR SHOWERS OVER THE SW CARIBBEAN...PANAMA...AND COSTA
RICA.

THE ATLANTIC OCEAN...
THE TAIL END OF A COLD FRONT ENTERS THE W ATLANTIC NEAR 32N68W
AND EXTENDS S TO THE CENTRAL BAHAMAS NEAR 25N76W. ISOLATED
MODERATE CONVECTION IS E OF THE FRONT FROM 28N-30N BETWEEN
66W-71W. ELSEWHERE...ANOTHER COLD FRONT EXTENDS FROM THE E
ATLANTIC TO E OF THE LEEWARD ISLANDS ALONG 32N19W 18N37W 16N50W
18N60W. SCATTERED SHOWERS ARE WITHIN 60 NM OF THE OF THE FRONT.
A TIGHT SURFACE PRESSURE GRADIENT OVER THE E ATLANTIC W OF THE
COLD FRONT IS PRODUCING NEAR GALE FORCE WINDS N OF 28N BETWEEN
30W-38W. IN THE UPPER LEVELS...A RIDGE IS OVER THE W ATLANTIC W
OF 55W. AN UPPER LEVEL TROUGH IS FURTHER E OVER THE CENTRAL
ATLANTIC BETWEEN 40W-55W. AN UPPER LEVEL HIGH IS CENTERED NE OF
THE CAPE VERDE ISLANDS NEAR 19N16W. AN UPPER LEVEL RIDGE EXTENDS
N FROM THIS CENTER TO BEYOND THE CANARY ISLANDS. EXPECT OVER THE
NEXT 24 HOURS...FOR THE SURFACE TROUGH OVER THE W ATLANTIC TO
MOVE E...AND FOR THE COLD FRONT TO BECOME STATIONARY WITH MORE
SHOWERS.

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

$$
FORMOSA






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