000
AXNT20 KNHC 271748
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST FRI NOV 27 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...ITCZ/MONSOON TROUGH...                                      

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 11N14W TO
05N20W...WHERE THE INTERTROPICAL CONVERGENCE ZONE AXIS BEGINS
AND EXTENDS TO 03N30W TO 05N40W TO 05N49W. ISOLATED MODERATE
CONVECTION IS FROM 03N TO 14N BETWEEN 30W AND 42W. 

...DISCUSSION...

GULF OF MEXICO...                                              

SURFACE HIGH PRESSURE CENTERED OVER THE SE US SUPPORTS MODERATE
TO FRESH EASTERLY FLOW OVER THE EASTERN GULF...AND MODERATE TO
FRESH SE FLOW OVER THE WESTERN GULF. DRY AIR ALOFT AND
SUBSIDENCE IS INHIBITING ANY DEEP CONVECTION ACROSS THE GULF
BASIN. HOWEVER...SHALLOW LOW LEVEL MOISTURE IN THE EASTERLY FLOW
IS SUPPORTING ISOLATED TO SCATTERED SHOWERS ACROSS THE GULF
BASIN. OVER THE NEXT 24 HOURS THE HIGH PRESSURE SYSTEM WILL
REMAIN NEARLY STATIONARY WHILE WEAKENING. THE WEAKENING OF THE
HIGH WILL RESULT IN WINDS DECREASING BY A FEW KT OVER THE GULF
SAT AND SAT NIGHT. A COLD FRONT WILL APPROACH THE TX GULF COAST
SAT AFTERNOON. THIS WILL BRING INCREASING CHANCES FOR CONVECTION
OVER THE EXTREME NW GULF SAT AND SAT NIGHT. 
 
CARIBBEAN SEA...                                               

AN UPPER TROUGH EXTENDS FROM THE SW N ATLC TO E CUBA TO THE
CENTRAL CARIBBEAN. THIS TROUGH SUPPORTS A SHEAR LINE THAT
CROSSES HAITI NEAR 19N73W TO JAMAICA NEAR 18N77W TO THE COAST OF
HONDURAS NEAR 16N84W. UPPER LEVEL SUPPORT FROM THE TROUGH AND
LOW LEVEL CONVERGENCE FROM THE SHEAR LINE IS HELPING TO GENERATE
CLUSTERS OF THUNDERSTORMS FROM 15N TO 20N BETWEEN 71W AND 77W.
FRESH TO STRONG NE WINDS ARE N OF THE SHEAR LINE. MODERATE TO
FRESH EASTERLY TRADE WINDS ARE S OF THE SHEAR LINE. THE AREA OF
HIGH PRESSURE OVER THE SE US WHICH IS SUPPORTING THE TIGHT
PRESSURE GRADIENT N OF THE SHEAR LINE WILL WEAKEN SLIGHTLY OVER
THE NEXT 24 HOURS...WHICH SHOULD IN TURN HELP TO DISSIPATE THE
SHEAR LINE. MID TO UPPER LEVEL TROUGHING WILL PERSIST FROM THE
SW N ATLC TO THE SW CARIBBEAN OVER THE WEEKEND...WHICH
WILL CONTINUE TO SUPPORT PERIODS OF CONVECTION. 
 
...HISPANIOLA...                                               

THE COMBINATION OF AN UPPER LEVEL TROUGH OVER THE REGION AND A
SHEAR LINE TRAVERSING HAITI SUPPORTS CLUSTERS OF THUNDERSTORMS
MAINLY OVER HAITI AND OFFSHORE WATERS THIS AFTERNOON. LOCALLY
HEAVY RAINFALL WILL BE POSSIBLE AS THESE STORMS MAY PERSIST INTO
THE EVENING. EXPECT SCATTERED THUNDERSTORMS TO REMAIN POSSIBLE
MAINLY OVER THE WESTERN PORTION OF HISPANIOLA TONIGHT THROUGH
SATURDAY.

ATLANTIC OCEAN...                                              

AN UPPER TROUGH EXTENDS FROM 35N70W TO THE CENTRAL BAHAMAS TO
NEAR JAMAICA. THE SURFACE REFLECTION OF THIS FEATURE IN THE
FORM OF A SURFACE TROUGH EXTENDS FROM 31N64W TO 25N65W TO
21N69W...WHERE IT TRANSITIONS TO A SHEAR LINE TO 19N73W.
SCATTERED MODERATE CONVECTION IS WITHIN 250 NM OF EITHER SIDE OF
THE SURFACE TROUGH. SHOWERS AND ISOLATED THUNDERSTORMS ARE FROM
22N TO 26N BETWEEN 71W AND 77W...INCLUDING THE CENTRAL BAHAMAS.
A TIGHT PRESSURE GRADIENT CONTINUES BETWEEN HIGH PRESSURE OVER
THE SE US AND THE SURFACE TROUGH...SUPPORTING FRESH TO STRONG NE
WINDS NW OF THE SURFACE TROUGH TO THE FL COAST. FARTHER
EAST...AN UPPER LOW CENTERED NEAR 26N29W SUPPORTS ISOLATED
MODERATE CONVECTION WITHIN 100 NM OF THE UPPER LOW. OVER THE
NEXT 24 HOURS THE SURFACE TROUGH WILL DRIFT W WITH CONVECTION. 

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

$$
LATTO