000
AXNT20 KNHC 160546
TWDAT 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL 
205 AM EDT TUE APR 16 2013

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 EXTENDS FROM THE AFRICAN COAST NEAR 07N12W TO 
05N14W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 
05N14W TO 04N21W TO THE EQUATOR NEAR 26W. WIDELY SCATTERED 
MODERATE CONVECTION IS FROM 04N-11N BETWEEN 06W-13W.

...DISCUSSION...

GULF OF MEXICO...                                             
MIDDLE TO UPPER LEVEL RIDGING IS NOTED ON WATER VAPOR IMAGERY AS 
MOSTLY DRY AIR AND OVERALL SUBSIDENCE DOMINATES THE ATMOSPHERE 
ALOFT FOR THE OVERNIGHT PERIOD. AT THE SURFACE...THE WESTERN 
PERIPHERY OF A RIDGE CONTINUES TO PROVIDE SOUTHEASTERLY WINDS IN 
THE RANGE OF 10 TO 20 KT. THIS OVERALL SYNOPTIC PATTERN IS 
FORECAST TO PERSIST THROUGH EARLY THURSDAY AS WINDS GRADUALLY 
INCREASE W OF 90W DUE TO A STRENGTHENING PRESSURE GRADIENT ON 
THE HEELS OF DEVELOPING LOW PRESSURE ACROSS THE CENTRAL PLAINS. 
THE ASSOCIATED COLD FRONT IS EXPECTED TO EMERGE OFF THE TEXAS 
AND LOUISIANA COAST LATE THURSDAY INTO EARLY FRIDAY.

CARIBBEAN SEA...                                                
A MIDDLE TO UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED 
NEAR 14N80W AND COTNINUES TO PROVIDE OVERALL STABLE AND DRY 
CONDITIONS ALOFT OVER MUCH OF THE CARIBBEAN THIS EVENING. TRADES 
PERSIST UNDER THESE FAIR CONDITIONS IN THE RANGE OF 15 TO 25 KT 
WITH THE HIGHEST WINDS GENERALLY OCCURRING S OF 16N BETWEEN 66W-
78W...AND IN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. THIS 
OVERALL SYNOPTIC PATTERN IS EXPECTED TO PERSIST THROUGH THE 
WEEK.

ATLANTIC OCEAN...                                               
A MID-LEVEL SHORTWAVE TROUGH CONTINUES TO EMBED ITSELF WITHIN 
LARGER LONGWAVE TROUGHING OVER THE SW NORTH ATLC WITH AXIS FROM 
35N64W TO 26N78W THAT SUPPORTS A 1013 MB LOW CENTERED NEAR 
32N76W. A STATIONARY FRONT EXTENDS EASTWARD FROM THE LOW CENTER 
TO 31N59W AND A WEAK COLD FRONT EXTENDS SW TO THE FLORIDA 
PENINSULA COAST NEAR 28N81W. ISOLATED SHOWERS ARE OCCURRING 
WITHIN 180 NM EITHER SIDE OF THE STATIONARY FRONT. WITH THE LOSS 
OF THE MIDDLE TO UPPER LEVEL DYNAMIC SUPPORT AS IT MOVES 
EASTWARD...THE LOW IS EXPECTED TO GRADUALLY WEAKEN BY WEDNESDAY 
OVER PORTIONS OF THE SW NORTH ATLC. THE REMAINDER OF THE CENTRAL 
AND EASTERN ATLC REMAIN TRANQUIL AND UNDER THE INFLUENCE OF A 
SURFACE RIDGE ANCHORED BY A 1023 MB HIGH CENTERED NEAR 28N58W. 
THE SURFACE RIDGE AXIS EXTENDS EASTWARD TO 26N40W TO BEYOND 
32N22W AND INTO A 1026 MB HIGH CENTERED NEAR 36N16W. 

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

$$
HUFFMAN