[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 211701
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT THU OCT 21 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1645 UTC.

...TROPICAL WAVES...

TROPICAL WAVE IS ALONG 30W/31W FROM 4N-17N AND MOVING WESTWARD
AT 8 KNOTS OVER THE PAST 24 HOURS. CYCLONIC CURVATURE OF THE
CLOUD FIELD IS NOTED ON SATELLITE IMAGERY. SCATTERED SHOWERS ARE
NOTED FROM 14N-18N BETWEEN 25W-34W.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 10N15W 8N20W 9N30W 6N35W 11N44W
11N61W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 3N-8N
BETWEEN 18W-23W. ISOLATED MODERATE CONVECTION IS FROM 1N-6N
BETWEEN 30W-37W.

...DISCUSSION...

GULF OF MEXICO...
A 1028 MB HIGH CENTERED OVER WESTERN NORTH CAROLINA NEAR 36N83W
IS PRODUCING SURFACE RIDGING OVER THE ENTIRE GULF OF MEXICO. THE
SURFACE PRESSURE GRADIENT HAS INCREASED OVER THE GULF...THUS
WINDS ARE NOW 15-20KT FROM THE NE OVER THE E GULF E OF 90W...AND
15-20KT FROM THE SE OVER THE W GULF. PATCHES OF BROKEN TO
OVERCAST LOW CLOUDS ARE OVER THE GULF. IN THE UPPER LEVELS... AN
UPPER LEVEL TROUGH IS OVER THE FAR E GULF AND FLORIDA. AN UPPER
LEVEL HIGH IS CENTERED OVER S MEXICO NEAR 18N98W. UPPER LEVEL
RIDGING IS OVER THE W GULF W OF 85W PRODUCING NW FLOW. STRONG
SUBSIDENCE IS OVER THE E GULF E OF 87W WHILE CONSIDERABLE
MOISTURE IS OVER THE W GULF. WITHIN 24 HOURS...A COLD FRONT WILL
BE APPROACHING THE TEXAS COAST. EXPECT PREFRONTAL CONVECTION
OVER THE NW GULF OVER THE NEXT 24 HOURS.

CARIBBEAN SEA...
RESIDUAL CONVECTION ASSOCIATED WITH A DISSIPATED STATIONARY
FRONT IS SOUTH OF CUBA FROM 17N-20N BETWEEN 75W-85W. A
QUASI-STATIONARY 1008 MB LOW IS CENTERED OVER THE SW CARIBBEAN
NEAR 11N82W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 8N-14N
BETWEEN 76W-84W. A 1010 MB LOW IS LOCATED IN THE GULF OF
HONDURAS NEAR 17N88W. SCATTERED SHOWERS ARE WITHIN 60 NM OF THE
CENTER. THE E CARIBBEAN E OF 70W HAS MOSTLY FAIR WEATHER...
HOWEVER ISOLATED SHOWERS ARE NOTED. MODERATE TO FRESH TRADEWINDS
ARE OVER THE CARIBBEAN. IN THE UPPER LEVELS...UPPER LEVEL
TROUGHING IS OVER THE WESTERN AND EASTERN CARIBBEAN...WITH
RIDGING PREVAILING IN THE CENTRAL CARIBBEAN. SIGNIFICANT UPPER
LEVEL MOISTURE IS OVER THE W CARIBBEAN W OF 70W. STRONG
SUBSIDENCE IS OVER THE E CARIBBEAN. EXPECT THE LOW IN THE GULF
OF HONDURAS TO DISSIPATE WHILE THE LOW IN THE SW CARIBBEAN TO
REMAIN STATIONARY OVER THE NEXT 24 HOURS.

ATLANTIC OCEAN...
THE TAIL END OF A COLD FRONT IS OVER THE W ATLANTIC FROM 32N53W
TO 28N59W. A DISSIPATING STATIONARY FRONT CONTINUES TO E CUBA
ALONG 24N67W 20N74W. WIDELY SCATTERED MODERATE CONVECTION IS
OVER THE S BAHAMAS FROM 21N-25N BETWEEN 70W-75W. SCATTERED
SHOWERS ARE OVER THE REMAINDER OF THE FRONT. A SURFACE TROUGH IS
FROM 28N51W TO 19N55W. AN EMBEDDED 1010 MB LOW IS ON THE TROUGH
AXIS NEAR 25N52W. A 1019 MB HIGH IS OVER THE CENTRAL ATLANTIC
NEAR 28N29W. IN THE TROPICS...A 1009 MB LOW IS JUST NORTH OF THE
ITCZ NEAR 13N40W. SCATTERED SHOWERS ARE WITHIN 90 NM OF THE
CENTER. IN THE UPPER LEVELS...AN UPPER LEVEL TROUGH IS OVER THE
W ATLANTIC N OF 20N AND W OF 70W. AN UPPER LEVEL RIDGE IS
BETWEEN 55W-70W. AN UPPER LEVEL LOW IS OVER THE CENTRAL ATLANTIC
NEAR 24N47W. UPPER LEVEL DIFFLUENCE E OF THE CENTER IS PRODUCING
WIDELY SCATTERED MODERATE CONVECTION FROM 23N-31N BETWEEN
38W-48W. AN UPPER LEVEL HIGH IS OVER THE TROPICAL ATLANTIC NEAR
10N40W. AN UPPER LEVEL RIDGE AXIS EXTENDS NE FROM THIS CENTER TO
25N25W. EXPECT...MORE CONVECTION ALONG THE ITCZ ESPECIALLY E OF
35W OVER THE NEXT 24 HOURS.

$$
AL/MRF




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