000
AXNT20 KNHC 271129
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST TUE JAN 27 2009

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...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1115 UTC.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 4N8W 2N24W 1N40W TO THE EQUATOR 50W. 
SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 120 NM N OF 
THE AXIS BETWEEN 36W-41W. SIMILAR CONVECTION IS S OF 5N W OF 
47W. 
 
...DISCUSSION...

THE GULF OF MEXICO...
FAIR AND MILD CONDITIONS EXIST ACROSS THE GULF BENEATH SLIGHT 
RIDGING ALOFT AND E TO SE LOW-LEVEL FLOW ON THE S/SW PERIPHERY 
OF W ATLC HIGH PRES. THERE COULD BE A FEW SHOWERS OVER THE 
STRAITS OF FLORIDA AND FAR SE WATERS ASSOCIATED WITH WEAK 
TROUGHING E OF THE AREA. THIS RATHER TRANQUIL PATTERN IS 
EXPECTED TO CONTINUE UNTIL THE NEXT FRONT ENTERS THE NW WATERS 
TUE NIGHT. NWP MODELS ARE SHOWING SUFFICIENT UPPER SUPPORT TO 
PUSH THIS FRONT THROUGH THE ENTIRE GULF BY THE END OF THE 
WEEK...BRINGING STRONG N WINDS AND COOLER AIR TO THE REGION. 

THE CARIBBEAN SEA...
SFC OBS AND QSCAT DATA REVEAL STRONG ELY TRADES ACROSS THE  
CARIBBEAN WITH SPEEDS MAINLY IN THE 20-25 KT RANGE...EXCEPT TO 
GALE FORCE NEAR THE COAST OF COLOMBIA AS NOTED IN HI-RES QSCAT 
DATA AND A COUPLE OF SHIP REPORTS. THIS STRONG FLOW IS 
GENERATING ENOUGH INSTABILITY TO PRODUCE PATCHES OF LOW-LEVEL 
CLOUDS WITH EMBEDDED SHOWERS. CLOUDINESS APPEARS MOST ORGANIZED 
OVER THE NW CARIBBEAN LIKELY ENHANCED SOME BY A SFC TROUGH OVER 
THE WRN ATLC. HOWEVER...ALL OF THIS MOISTURE IS SHALLOW IN 
NATURE CAPPED BY ABUNDANT DRY STABLE AIR ALOFT...AS NOTED IN 
SOUNDINGS AND WATER VAPOR IMAGERY. TRADE WINDS ARE EXPECTED TO 
SLACKEN OVER THE W CARIBBEAN BY WED IN RESPONSE TO A FRONTAL 
BOUNDARY...EXPECTED TO ENTER THE AREA ON FRI.
 
THE ATLANTIC OCEAN...
THE ATLC DISCUSSION ZONE REMAINS QUIET TONIGHT WITH THE ONLY 
SYNOPTIC SFC FEATURES BEING A COUPLE OF LINGERING SFC TROUGHS 
OVER THE W ATLC. ONE OLD FRONTAL BOUNDARY EXTENDS FROM 32N46W TO 
26N59W TO 22N68W. SCATTERED CLOUDS AND EMBEDDED SHOWERS ARE 
WITHIN 240 NM W OF THE TROUGH AXIS. THE OTHER TROUGH LINE 
EXTENDS FROM BERMUDA TO 28N72W MARKED BY A NARROW LINE OF LOW 
CLOUDS. A WEAK COLD FRONT IS LOCATED TO THE NW OF THIS TROUGH 
ALONG THE NRN BORDER...BUT IS PRODUCING LITTLE SENSIBLE WEATHER 
IN THE REGION. FARTHER E...STRONG HIGH PRES CENTERED NEAR 33N22W 
IS MAINTAINING 20-25 KT NE/E TRADES ACROSS THE TROPICAL ATLC. 
THE UPPER LEVEL PATTERN IS RATHER BENIGN. DIFFLUENCE ALOFT 
BETWEEN WEAK TROUGHING OVER THE CENTRAL ATLC AND A E ATLC RIDGE 
IS PRODUCING A BROKEN PLUME OF HIGH LEVEL CLOUDINESS...BUT NOT 
MUCH IN THE WAY OF SIGNIFICANT MOISTURE. OTHERWISE...FAIRLY 
STABLE CONDITIONS ARE PRESENT ELSEWHERE.  
 
$$
CANGIALOSI