[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 110547
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST FRI DEC 11 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0515 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH AXIS EXTENDS ALONG THE COAST OF AFRICA FROM
03N AND THE PRIME MERIDIAN TO SOUTHERN LIBERIA NEAR 05N09W...
WHERE THE INTERTROPICAL CONVERGENCE ZONE AXIS BEGINS AND EXTENDS
TO 05N20W TO 04N30W TO 00N50W. ISOLATED TO SCATTERED MODERATE
CONVECTION IS FROM 03N-07N BETWEEN 36W AND 42W...AND WITHIN 150
NM N OF AXIS BETWEEN 21W AND 25W.

...DISCUSSION...

GULF OF MEXICO...

A 1019 MB HIGH PRES LOCATED OVER THE NE GULF NEAR 29N83W EXTENDS
A RIDGE ACROSS THE REGION PRODUCING MAINLY A GENTLE TO MODERATE
ANTICYCLONIC WIND FLOW AND GENERALLY FAIR WEATHER. SOUTHERLY
RETURN FLOW IN THE 15-20 KT RANGE IS ALREADY NOTED ACROSS THE NW
GULF. THE HIGH PRES WILL MOVE NE INTO THE ATLANTIC OCEAN OVER
THE NEXT 24 HOURS KEEPING A RIDGE ACROSS THE GULF REGION. ON
SATURDAY...THE PRESSURE GRADIENT WILL INCREASE OVER THE WESTERN
GULF BETWEEN THE HIGH OVER THE ATLC AND LOW PRESSURE DEVELOPING
INLAND OVER THE CENTRAL UNITED STATES. THE RESULT COULD BE FRESH
TO STRONG SOUTHERLY WINDS OVER THE NW GULF BY SAT AFTERNOON. THE
NEXT COLD FRONT IS FORECAST TO ENTER THE GULF ON SUN FOLLOWED BY
FRESH TO STRONG NORTHERLY WINDS AND BUILDING SEAS. ALOFT...A MID
TO UPPER LEVEL TROUGH EXTENDS FROM TAMPA BAY FLORIDA TO THE
YUCATAN PENINSULA. NW WINDS AND MODERATE TO STRONG SUBSIDENCE IS
NOTED IN THE WAKE OF THE TROUGH WHILE STRONG SOUTHWESTERLY WINDS
ARE AHEAD OF THE TROUGH AXIS. THESE WINDS ARE TRANSPORTING
ABUNDANT MID-UPPER LEVEL MOISTURE ACROSS SOUTHERN MEXICO AND THE
NW CARIBBEAN INTO CUBA AND THE BAHAMAS.

CARIBBEAN SEA...

THE AFOREMENTIONED MID TO UPPER LEVEL TROUGH OVER THE SE GULF OF
MEXICO IS HELPING TO INDUCE SOME CONVECTIVE ACTIVITY OVER PARTS
OF EASTERN CUBA...THE CAYMAN ISLANDS AND JAMAICA. THIS TROUGH
ALOFT IS FORECAST TO SHIFT EASTWARD EXTENDING ACROSS CENTRAL
CUBA TODAY AND ACROSS EASTERN CUBA ON SAT. AS A RESULT...
ABUNDANT MOISTURE AND THE FOCUS FOR CONVECTION WILL PERSIST OVER
PARTS OF EASTERN CUBA...THE CAYMAN ISLANDS AND JAMAICA THIS
FRI...WITH THESE CONDITIONS EXTENDING OVER HISPANIOLA MAINLY ON
SAT. PATCHES OF LOW LEVEL MOISTURE EMBEDDED IN THE TRADE WIND
FLOW ARE NOTED ACROSS THE REMAINDER OF THE BASIN...MORE
CONCENTRATED OVER THE WINDWARD ISLANDS AND THE EASTERN CARIBBEAN
PARTICULARLY E OF 65W. THE ATLC HIGH PRES NE OF AREA CONTINUES
TO PRODUCE FRESH TO STRONG TRADE WINDS ACROSS THE SOUTH-CENTRAL
CARIBBEAN. THE MOST RECENT SCATTEROMETER PASSES CONFIRMED THE
PRESENCE OF THESE WINDS. MODERATE TO FRESH WINDS DOMINATE THE
REMAINDER OF THE CENTRAL CARIBBEAN WITH GENTLE TO MODERATE WINDS
ELSEWHERE. THIS WEATHER PATTERN WILL PERSIST THROUGH THE
WEEKEND.

...HISPANIOLA...

AS PREVIOUSLY MENTIONED...THE ARRIVAL OF A MID-UPPER LEVEL TROUGH
FROM THE WEST WILL INCREASE THE POSSIBILITY OF RAIN ACROSS
HISPANIOLA LATE FRI THROUGH LIKELY SUN. UPPER DIFFLUENCE AHEAD
OF THE TROUGH WILL SUPPORT THE DEVELOPMENT OF SOME SHOWER AND
TSTM ACTIVITY ACROSS PARTS OF THE ISLAND.

ATLANTIC OCEAN...

THE LOW PRES SYSTEM THAT DEVELOPED ON THU EAST OF THE BAHAMAS
HAS MOVED QUICKLY TO THE NE AND CURRENTLY IS LOCATED JUST SE OF
BERMUDA NEAR 31N63W. A COLD FRONT EXTENDS FROM THE LOW CENTER
ACROSS THE CENTRAL BAHAMAS TO NEAR THE COAST OF CENTRAL CUBA.
SOME SHOWER ACTIVITY IS NOTED ALONG THE FRONTAL BOUNDARY. A 1023
MB HIGH PRES CENTERED NEAR 26N48W IS AHEAD OF THE FRONT AND
EXTENDS A RIDGE ACROSS THE CENTRAL ATLC INTO THE NE CARIBBEAN.
THIS SYSTEM WILL REMAIN NEARLY STATIONARY OVER THE NEXT 24
HOURS. ANOTHER COLD FRONT IS ENTERING THE FORECAST AREA BETWEEN
42W AND 52W WHILE ANOTHER RIDGE DOMINATES THE REMAINDER OF THE
FORECAST AREA. A MID-UPPER LEVEL TROUGH MOVING ACROSS THE
EASTERN U.S. AND THE FAR SE GULF OF MEXICO SUPPORTS THE FIRST
COLD FRONT. A DIFFLUENT PATTERN ALOFT AHEAD OF THE TROUGH AXIS
IS HELPING TO INDUCE SOME CONVECTIVE ACTIVITY ACROSS THE BAHAMAS
AND THE WESTERN ATLC. CONVECTION IS FORECAST TO CONTINUE OR
INCREASE OVER THE BAHAMAS AS THE REMNANTS OF THE COLD FRONT
INTERACT WITH THE ABOVE MENTIONED UPPER LEVEL TROUGH. ON SAT...A
TROUGH IS EXPECTED TO DEVELOP E OF THE BAHAMAS LIKELY ALONG THE
TAIL END OF THE COLD FRONT AND WILL DRIFT WESTWARD THROUGH SUN.
THIS WILL BE ANOTHER FACTOR THAT WILL SUPPORT SOME SHOWER AND
TSTM ACTIVITY ACROSS THE BAHAMAS AND REGIONAL WATERS.

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

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