[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 282346
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST MON JAN 28 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2315 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE PRIME MERIDIAN AT 03N TO
03N16W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM
03N16W TO 02N30W TO 04N44W TO 02N50W. SCATTERED MODERATE
CONVECTION IS FROM THE EQUATOR TO 06N BETWEEN THE PRIME MERIDIAN
AND 04W.

...DISCUSSION...

GULF OF MEXICO...
VERY WEAK AND BROAD UPPER LEVEL TROUGHING IS ACROSS THE GULF...
HOWEVER OVERRIDING THIS SUBTLE FEATURE IS A MID-LEVEL RIDGE THAT
REMAINS ANCHORED OVER THE CARIBBEAN SEA. WATER VAPOR IMAGERY
INDICATES A FAIRLY DRY AND STABLE AIRMASS IS OVER MUCH OF THE
GULF THIS EVENING. AT THE SURFACE...THE WESTERN PERIPHERY OF A
SURFACE RIDGE...ANCHORED BY A 1032 MB HIGH CENTERED IN THE SW
NORTH ATLC NEAR 33N72W...IS PROVIDING SE WINDS IN THE RANGE OF
10 TO 20 KT AND MOSTLY CLEAR SKIES WITH FAIR CONDITIONS. A WEAK
SURFACE TROUGH EMBEDDED WITHIN THE RIDGING IS ANALYZED FROM
25N88W TO 28N86W AND IS GENERATING ISOLATED SHOWERS AND TSTMS
FROM 26N-28N BETWEEN 85W-88W. THIS ACTIVITY IS EXPECTED TO
CONTINUE MOVING NE THROUGH THE EVENING HOURS. THE SURFACE RIDGE
IS EXPECTED TO GRADUALLY SLIDE EASTWARD THROUGH EARLY WEDNESDAY
AS SOUTHERLY FLOW INCREASES ACROSS THE GULF. BY EARLY
WEDNESDAY...THE NEXT COLD FRONT IS FORECAST TO EMERGE OFF THE
TEXAS AND LOUISIANA COAST SHIFTING WINDS NORTHERLY BEHIND THE
FRONT.

CARIBBEAN SEA...
SOUTH-SOUTHWESTERLY FLOW ALOFT DOMINATES OVER THE CARIBBEAN SEA
THIS EVENING AS WATER VAPOR IMAGERY INDICATES A VERY DRY AND
SUBSIDENT ATMOSPHERE IS IN PLACE DUE TO A MID-LEVEL RIDGING
ANCHORED OVER THE BASIN NEAR 17N73W. WHILE THE MIDDLE TO UPPER
LEVELS ARE PROVIDING FAIRLY BENIGN WEATHER...AT THE SURFACE THE
TRADE WINDS REMAIN IN THE RANGE OF 15 TO 25 KT...WITH HIGHER
WINDS POSSIBLE IN CLOSE PROXIMITY TO THE COAST OF COLOMBIA...DUE
TO A STRONG PRESSURE GRADIENT BETWEEN STRONG SURFACE RIDGING
OVER THE SW NORTH ATLC REGION AND LOWER PRESSURE LOCATED OVER
THE NORTHERN SOUTH AMERICAN CONTINENT. ISOLATED SHOWERS ARE
NOTED ON SATELLITE IMAGERY ACROSS THE BASIN THIS EVENING...WITH
THE MOST CONCENTRATED AREAS E OF 70W...AND ACROSS PORTIONS OF
THE NW CARIBBEAN AND WESTERN CUBA. OVERALL LITTLE CHANGE IS
EXPECTED SYNOPICALLY OVER THE NEXT 24 TO 36 HOURS.

ATLANTIC OCEAN...
SURFACE HIGH PRESSURE IS CONTROLLING THE SW NORTH ATLC ANCHORED
BY A 1032 MB HIGH CENTERED NEAR 33N72W. THE HIGH IS SUPPORTED BY
A MIDDLE TO UPPER LEVEL RIDGE COVERING THE EASTERN CONUS. EAST
OF THE RIDGING...BROAD UPPER LEVEL TROUGHING IS NOTED ON WATER
VAPOR IMAGERY N OF 27N BETWEEN 30W-60W THAT SUPPORTS A PAIR OF
FRONTAL BOUNDARIES ENTERING THE DISCUSSION AREA IN THE CENTRAL
ATLC. THE EASTERN-MOST FRONT IS A DISSIPATING COLD FRONT
ANALYZED FROM 32N39W TO 25N50W TO 21N62W...AND THE WESTERN-MOST
COLD FRONT IS ANALYZED FROM 32N41W TO 25N54W TO 24N66W...THEN
CONTINUES AS A DIFFUSE CLOUD LINE NW TO 27N78W NEAR THE NW
BAHAMAS. WIDELY SCATTERED SHOWERS ARE OCCURRING WITHIN 150 NM
EITHER SIDE OF THE FRONTS E OF 64W. THE REMAINDER OF THE EASTERN
ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A
1031 MB HIGH CENTERED OVER THE IBERIAN PENINSULA NEAR 39N06W.
THE RIDGE AXIS EXTENDS FROM THE HIGH SW TO 20N40W.

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

$$
HUFFMAN




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