[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 181101
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST TUE DEC 18 2007

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN
SECTIONS OF SOUTH AMERICA...AND THE 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
1015 UTC

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 7N11W 5N17W 5N24W 3N38W 3N53W.
SCATTERED MODERATE WITH EMBEDDED CLUSTERS OF ISOLATED STRONG
CONVECTION ARE FROM 1N TO THE COAST OF SW AFRICA BETWEEN 3W-6W.
CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE
WITHIN 60 NM OF THE ITCZ AXIS FROM 26W-38W. AN AREA OF UPPER
DIFFLUENCE COUPLED WITH TROPICAL MOISTURE IS GENERATING
SCATTERED MODERATE/ISOLATED STRONG CONVECTION FROM 4N-8N BETWEEN
45W-49W.

DISCUSSION...
GULF OF MEXICO...
ZONAL WESTERLY UPPER FLOW DOMINATES THE GULF THIS MORNING WITH A
JETSTREAM OF WINDS ESTIMATED TO BE 80 TO 110 KT OVER THE N GULF
AND THE SE US N OF 25N FROM TEXAS INTO THE W ATLC. A SURFACE
RIDGE DOMINATES THE GULF ANCHORED OVER THE E US WITH A 1030 MB
HIGH OVER SE ALABAMA. RETURN FLOW AROUND THIS SURFACE RIDGE IS
BANKING LOW LEVEL CLOUDS WITH WIDELY ISOLATED SHOWERS OVER THE W
AND CENTRAL GULF TO THE SIERRA MADRE MOUNTAINS LEAVING THE E
GULF WITH CLEAR SKIES E OF 86W TO OVER FLORIDA. HIGH PRESSURE
WILL REMAIN IN CONTROL OF THE GULF WITH THE NEXT FRONT MOVING IN
LATE IN THE WEEK.

CARIBBEAN SEA...
BROAD UPPER RIDGE COVERS THE W CARIBBEAN W OF 75W WITH THE RIDGE
AXIS EXTENDING FROM THE GULF OF HONDURAS ENE ACROSS HISPANIOLA
INTO THE W/CENTRAL ATLC. AN UPPER TROUGH COVERS THE REMAINDER OF
THE CARIBBEAN EXTENDING FROM THE VIRGIN ISLANDS TO OVER
COLOMBIA. DRY STABLE AIR REIGNS OVER MOST OF THE CARIBBEAN
EXCEPT W OF A NEAR STATIONARY FRONTAL BOUNDARY THAT EXTENDS
ACROSS E CUBA NEAR 20N76W TO HONDURAS NEAR 15N85W. MOSTLY
OVERCAST LOW CLOUDS WITH ISOLATED SHOWERS ARE W OF THE FRONT.
THE REMAINDER OF THE CARIBBEAN HAS WIDELY SCATTERED LOW LEVEL
CLOUDS BUT REMAINS RATHER TRANQUIL THIS MORNING. MODERATE/STRONG
NE TO E WINDS DOMINATE THE CARIBBEAN.

ATLANTIC OCEAN...
THE DEEP LAYERED TROUGH THAT COVERS THE FAR NE US AND THE W ATLC
W OF 62W WITH THE ASSOCIATED COLD FRONT ENTERING THE REGION NEAR
32N60W TO THE TURKS AND CAICOS BECOMING NEAR STATIONARY THEN
CONTINUING INTO THE CARIBBEAN OVER CUBA NEAR 20N76W. SCATTERED
SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 60 NM E OF THE FRONT N
OF 26N WITH MOSTLY OVERCAST LOW CLOUDS WITH WIDELY ISOLATED
SHOWERS WITHIN 150/200 NM W OF THE FRONT INTO THE CARIBBEAN. A
JETSTREAM WITH WINDS ESTIMATED TO BE 80 TO 110 KT COVERS THE W
ATLC N OF 24N W OF THE FRONT. AN UPPER RIDGE IN THE CARIBBEAN
EXTENDS ACROSS HISPANIOLA NEAR 20N71W TO 26N59W WITH A SECOND
UPPER HIGH CENTERED IN THE CENTRAL ATLC NEAR 30N48W. A DEEP
LAYERED TROUGH IS OVER E ATLC N OF 20N E OF 30W WITH THE
ASSOCIATED COLD FRONT ENTERING THE REGION NEAR 32N16W EXTENDING
ALONG 27N24W TO 25N31W THEN DISSIPATING TO NEAR 25N37W. A
SURFACE TROUGH IS TO THE E EXTENDING FROM 32N14W ACROSS THE
CANARY ISLANDS ALONG 26N20W TO 22N31W. SCATTERED SHOWERS/
ISOLATED THUNDERSTORMS ARE E OF THE FRONT N OF 27N TO INLAND
OVER AFRICA. A SURFACE RIDGE IS OVER CENTRAL ATLC BETWEEN THE
FRONTS. UPPER WESTERLY ZONAL FLOW COVERS THE TROPICS AND A WEAK
JETSTREAM WITH ESTIMATED WINDS OF 70 TO 95 KT EXTENDS ACROSS THE
TROPICS ALONG 16N52W 15N30W ACROSS THE CAPE VERDE ISLANDS TO
OVER AFRICA NEAR 19N16W. THE REMAINDER OF THE ATLC UNDER RATHER
TRANQUIL CONDITIONS AGAIN THIS MORNING.

$$
WALLACE




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