Tropical Weather Discussion
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000
AXNT20 KNHC 191119
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST FRI DEC 19 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1115 UTC.

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

THE MONSOON TROUGH CROSSES THE AFRICAN COAST NEAR 09N14W AND
CONTINUES OVER THE EASTERN ATLANTIC TO NEAR 07N16W WHERE THE
ITCZ BEGINS AND CONTINUES ALONG 06N32W TO THE NORTHERN COAST OF
BRAZIL NEAR 02N50W. SCATTERED MODERATE CONVECTION IS FROM 02N-
08N E OF 38W.

...DISCUSSION...

GULF OF MEXICO...

AN UPPER-LEVEL SW TO W FLOW PREVAILS ACROSS THE BASIN ADVECTING
MOISTURE FROM THE ITCZ IN THE EPAC MAINLY TO THE NORTHERN GULF
WATERS. LOW-LEVEL MOISTURE CONVERGENCE ALONG WITH MOISTURE ALOFT
SUPPORT SCATTERED MODERATE CONVECTION AND N OF 24N...W OF 87W. A
1014 MB SURFACE LOW IS OVER E CENTRAL MEXICO NEAR 22N98W. TO THE
N...A STATIONARY FRONT EXTENDS ALONG 28N96W TO 28N94W TO 27N92W.
A SURFACE RIDGE COVERING THE CENTRAL AND EASTERN U.S. ANCHORED
BY A 1027 MB HIGH CENTERED OVER W ILLINOIS EXTENDS SE INTO THE
NE GULF WATERS. RETURN FLOW OF 5-15 KT ASSOCIATED WITH THIS
RIDGE CONTINUES TO ADVECT DRY COOL AIR ACROSS THE REMAINDER
BASIN...SUPPORTING FAIR WEATHER AND CLEAR SKIES. OVER THE NEXT
48 HOURS...THE NEXT COLD FRONT WILL DEVELOP AND ENTER THE W GULF
WATERS ENHANCING CONVECTION.

CARIBBEAN SEA...

A SURFACE TROUGH OVER THE WESTERN BASIN EXTENDING FROM 20N85W TO
16N84W TO 11N83W. A HIGH LOW-LEVEL MOISTURE PLUME EXTENDS ACROSS
THE NW BASIN W OF 79W...WHICH ALONG THE SURFACE TROUGH ENHANCES
SCATTERED MODERATE CONVECTION FROM 15N-20N BETWEEN 80W-87W. A
SMALL UPPER-LEVEL TROUGH EXTENDS FROM THE ATLANTIC INTO THE
EASTERN CARIBBEAN MAINLY E OF 67W AFFECTING THE LEEWARD ISLANDS
AND PUERTO RICO. THIS TROUGH ALONG WITH LOW LEVEL MOISTURE IS
PRODUCING ISOLATED CONVECTION ACROSS THESE ISLANDS AND THEIR
ADJACENT WATERS. FAIR WEATHER PREVAILS ELSEWHERE ACROSS THE
BASIN SUPPORTED BY DRY AIR SUBSIDENCE FROM ALOFT. TRADES OF 10-
15 KT DOMINATE ACROSS THE BASIN. THE SURFACE TROUGH IS FORECAST
TO DISSIPATE LATER TODAY...HOWEVER LINGERING MOISTURE ASSOCIATED
WITH IT MAY STILL ENHANCE ISOLATED CONVECTION OVER THE NW BASIN
THROUGH LATE SATURDAY.

HISPANIOLA...

DRY AIR PREVAILS ACROSS THE ISLAND PROMOTING FAIR WEATHER
CONDITIONS. SIMILAR PATTERN IS EXPECTED TO CONTINUE OVER THE
NEXT 24 HOURS. MOISTURE IS EXPECTED TO INCREASE BY SATURDAY
INCREASING THE CHANCE OF SHOWERS FOR THE WEEKEND.

ATLANTIC OCEAN...

A PAIR OF COLD FRONTS ARE MOVING ACROSS THE W ATLANTIC. THE
FIRST FRONT EXTENDS FROM 31N72W TO 37N57W THEN INTO THE N
ATLANTIC WITH NO SIGNIFICANT CONVECTION ASSOCIATED TO IT. TO THE
E...ANOTHER COLD FRONT EXTENDS FROM 25N75W TO 32N58W TO 43N50W.
SCATTERED MODERATE CONVECTION REMAINS N OF 34N BETWEEN 46W-53W.
FURTHER E...AN UPPER-LEVEL TROUGH WITH AXIS ALONG 48W SUPPORTS A
1014 MB SURFACE LOW CENTERED NEAR 26N44W AND ITS ASSOCIATED COLD
FRONT THAT EXTENDS FROM THE LOW CENTER TO 21N46W. A STATIONARY
FRONT EXTENDS N FROM THIS LOW ALSO TO 44N28W. SCATTERED MODERATE
CONVECTION IS OBSERVED FROM 19N-36N BETWEEN 36W-47W. A 1034 MB
HIGH CONTINUES NEAR 39N19W SUPPORTING FAIR WEATHER ACROSS THE E
ATLANTIC. OVER THE NEXT 48 HOURS...EXPECT FOR THE FRONT ACROSS
THE W ATLANTIC TO MOVE E WHILE WEAKENING. THE LOW OVER THE
CENTRAL ATLANTIC WILL MOVE N ENHANCING CONVECTION WHILE THE
FRONTS ASSOCIATED TO IT WILL WEAKEN.

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

$$
ERA



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