000
AXNT20 KNHC 211151
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT WED OCT 21 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1015 UTC.

...ITCZ/MONSOON TROUGH...   
                                  
THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL 
ATLANTIC NEAR 14N17W TO A 1011 MB LOW NEAR 10N28W TO A SECOND 
1011 MB LOW NEAR 10N45W TO 09N48W WHERE THE ITCZ BEGINS AND 
CONTINUES TO 09N55W. A SURFACE TROUGH IS THE W OF THE ITCZ 
EXTENDING FROM 13N56W TO 10N58W. CLUSTERS OF MODERATE/ISOLATED 
STRONG CONVECTION ARE FROM 07N-17N BETWEEN 18W-30W AND 33W-43W.

...DISCUSSION...

GULF OF MEXICO... 
                                              
AN UPPER-LEVEL RIDGE COVERS THE GULF ANCHORED IN THE E PACIFIC 
REGION W OF THE GULF OF TEHUANTEPEC. AT THE SURFACE...A SHALLOW 
TROUGH EXTENDS FROM 25N93W TO THE E BAY OF CAMPECHE NEAR 21N93W. 
ISOLATED MODERATE CONVECTION IS OBSERVED IN THE VICINITY OF THIS 
TROUGH. TO THE SE...REMNANT MOISTURE ASSOCIATED WITH A RECENT 
FRONTAL PASSAGE IS STILL GENERATING ISOLATED CONVECTION MAINLY S 
OF 24N E OF 83W AFFECTING THE STRAITS OF FLORIDA. SCATTEROMETER 
DATA DEPICTS A GENTLE TO MODERATE NORTHERLY FLOW ACROSS THE 
WESTERN HALF OF THE BASIN WHILE MODERATE TO FRESH WINDS PREVAIL 
ACROSS THE EASTERN GULF. THESE STRONGER WINDS ARE SUPPORTED BY 
THE TIGHT PRESSURE GRADIENT BETWEEN THE SURFACE RIDGE EXTENDING 
FROM EASTERN US AND LOWER PRESSURE OVER THE YUCATAN PENINSULA. 
EXPECT FOR WINDS TO SUBSIDE OVER THE NEXT 24 HOURS. 

CARIBBEAN SEA... 
                                               
THE UPPER-LEVEL RIDGE THAT DOMINATES THE GULF OF MEXICO REACHES 
THE W CARIBBEAN MAINLY W OF 73W. TO THE E...AN ELONGATED UPPER-
LEVEL LOW IS CENTERED OVER W VENEZUELA WITH A TROUGH AXIS 
EXTENDING E-NE ACROSS THE WINDWARD ISLANDS AND INTO THE TROPICAL 
ATLANTIC. A STATIONARY FRONTAL BOUNDARY EXTENDS ACROSS CENTRAL 
CUBA AND CONTINUES E ACROSS THE BAHAMAS ENHANCING CONVECTION 
ACROSS PORTIONS OF CUBA...HISPANIOLA...JAMAICA...AND THE 
NORTHERN CARIBBEAN WATERS N OF 16N AND W OF 70W. SCATTEROMETER 
DATA DEPICTS GENTLE TO MODERATE TRADES ACROSS THE BASIN EXCEPT 
MODERATE TO FRESH WINDS S OF 13N BETWEEN 71W-76W. EXPECT OVER 
THE NEXT 24 HOURS FOR THE FRONTAL BOUNDARY TO WEAKEN OVER THE NW 
CARIBBEAN. A SURFACE TROUGH CURRENTLY AT ABOUT 265 NM E OF THE 
WINDWARD ISLANDS IS EXPECTED TO ENTER THE E CARIBBEAN WITH 
CONVECTION.
                                        
...HISPANIOLA...  
                                               
CURRENTLY SCATTERED SHOWERS/THUNDERSTORMS ARE ACROSS THE ISLAND 
AND ADJACENT ATLANTIC WATERS. A STATIONARY FRONTAL BOUNDARY N OF 
THE ISLAND IS PROVIDING MOISTURE AND INSTABILITY TO GENERATE 
THIS ACTIVITY. THE FRONT IS EXPECTED TO CONTINUE NEAR THE ISLAND 
THROUGH THE NEXT 24 HOURS THEREFORE A SIMILAR WEATHER PATTERN 
WILL CONTINUE. A WEAK LOW WILL DEVELOP ALONG THE FRONT E OF 
TURKS AND CAICOS AND RACE NE DRAGGING THE FRONT E BY THE END OF 
THE WEEK.

ATLANTIC OCEAN...
                                               
AN UPPER-LEVEL TROUGH COVERS THE W ATLANTIC SUPPORTING A 
STATIONARY FRONT THAT ENTERS THE AREA NEAR 22N78W AND EXTENDS TO 
23N67W TO 31N52W. SCATTERED MODERATE CONVECTION IS OBSERVED IN 
THE VICINITY OF THE FRONT FROM 19N-33N BETWEEN 51W-71W. THE 
REMAINDER OF THE BASIN IS DOMINATED BY A SURFACE RIDGE ANCHORED 
BY A 1029 MB HIGH CENTERED NEAR 39N30W. EXPECT OVER THE NEXT 24 
HOURS FOR THE FRONT TO CONTINUE ENHANCING CONVECTION ACROSS THE 
W-CENTRAL ATLANTIC. A WEAK LOW WILL DEVELOP ALONG THE FRONT E OF 
TURKS AND CAICOS AND RACE NE DRAGGING THE FRONT E BY THE END OF 
THE WEEK.

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

$$ 

ERA