[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 311149
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT SUN 31 OCT 2004

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHEASTERN
SECTIONS OF SOUTH AMERICA...AND ATLC 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1045 UTC.

...TROPICAL WAVES...

TROPICAL WAVE IS BETWEEN BARBADOS AND THE LESSER ANTILLES ALONG
60W/61W S OF 20N MOVING W 5-10 KT. THE WEAK 1012 MB LOW NEAR 18N
IN NO LONGER DISCERNIBLE. WAVE REMAINS UNDER SOME WESTERLY SHEAR
AT THE BASE OF A DEEP LAYERED TROUGH OVER THE CENTRAL ATLC.
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 60 NM OF
13N FROM 55W-58W. SCATTERED SHOWERS/THUNDERSTORMS ARE E OF THE
WAVE AXIS FROM 7N-19N W OF 52W.

TROPICAL WAVE LOCATED OVER THE W CARIBBEAN IS ALONG 83W S OF 18N
MOVING W NEAR 10 KT. WAVE IS MOVING OUT FROM UNDER THE WESTERN
EDGE OF A MID/UPPER LEVEL HIGH WITH THE NORTHERN PORTION OF THE
WAVE AXIS MOVING INTO AN AREA OF STRONG SUBSIDENCE/DRY AIR AT
THE UPPER LEVELS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION
IS S OF 10N TO THE COAST OF PANAMA FROM 81W TO THE BORDER OF
COSTA RICA. SCATTERED SHOWERS ARE FROM 12N-20N BETWEEN 78W-85W.

...ITCZ...

ITCZ AXIS IS ALONG 13N10W 7N25W 8N41W 10N48W 10N60W. SCATTERED
MODERATE/STRONG CONVECTION IS WITHIN 75/90 NM OF LINE 9N31W
10N49W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG
CONVECTION ARE FROM 3N-10N BETWEEN 30N-52W. ISOLATED CLUSTERS OF
SCATTERED MODERATE CONVECTION ARE FROM 1N-10N E OF 30W.

...DISCUSSION...

GULF OF MEXICO...NW CARIBBEAN AND ATLANTIC W OF 75W...
DRY/TRANQUIL WEATHER CONTINUES OVER THE GULF AND NW CARIBBEAN
INTO THE W ATLC WITH DEEP LAYERED RIDGING MAINTAINING CONTROL.
RIDGE IS ANCHORED BY A MID/UPPER LEVEL HIGH OVER THE CENTRAL
GULF WITH BROAD AXIS EXTENDING N FROM OVER THE SE UNITED STATES
TO THE W ATLC BETWEEN 70W-103W. THIS PATTERN IS KEEPING UPSTREAM
DISTURBANCES CONFINED OVER THE NORTH PORTION OF THE US AND
PRODUCING STRONG SUBSIDENCE OVER THE GULF INTO THE W ATLC
INCLUDING THE YUCATAN PENINSULA AND THE GREATER ANTILLES W OF
PUERTO RICO. AT THE SURFACE...RIDGE IS ANCHORED IN THE W ATLC
FROM A 1021 MB HIGH LOCATED SSW OF BERMUDA WITH AXIS EXTENDING
ACROSS N FLORIDA ALONG 30N TO LOUISIANA. RETURN FLOW OVER THE W
GULF HAS INCREASED AHEAD OF A STATIONARY FRONT THAT REMAINS
ACROSS CENTRAL TEXAS. CONDITIONS ACROSS THE GULF WILL REMAIN DRY
THROUGH TODAY.

REMAINDER OF THE CARIBBEAN...
MID/UPPER LEVEL HIGH IS OVER THE SW CARIBBEAN WITH RIDGE AXIS
EXTENDING N TO JUST W OF JAMAICA. WITH THE DEEP LAYERED TROUGH
TO THE N OVER THE CENTRAL ATLC...ZONAL WESTERLY FLOW DOMINATES
THE REMAINDER OF THE CARIBBEAN W OF 77W. THE UNSETTLED WEATHER
IS NOW CONFINED TO S OF 14N WITH SCATTERED MODERATE/ISOLATED
STRONG CONVECTION FROM 68W-75W. CLOUDINESS AND SCATTERED
SHOWERS/THUNDERSTORMS COVER THE E CARIBBEAN S OF 20N FROM
66W-70W. THE NW CARIBBEAN IS BECOMING UNSTABLE AS THE TROPICAL
WAVE NEAR 83W ADVECTS INCREASING MOISTURE WESTWARD.

ATLANTIC FROM 45W TO 75W...
LARGE MID/UPPER LEVEL TROUGH NOW COVERS THE ENTIRE AREA WITH
STRONG SUBSIDENCE AND VERY DRY AIR PREVAILING FROM THE GULF INTO
THE AREA. A BROAD SWATH OF DEEP LAYERED MOISTURE ACCOMPANIES A
SUBTROPICAL JET EXTENDING FROM 20N48W NE TO BEYOND 32N37W. GOOD
UPPER LEVEL DYNAMICS NEAR THE ENTRANCE REGION OF THE JET IS
PRODUCING AN AREA OF SHOWERS/THUNDERSTORMS WITHIN 120 NM OF THE
JET N OF 24N. AT THE SURFACE...A COLD FRONT IS TO THE W OF THE
JET EXTENDING THROUGH 32N41W TO 27N46W WITH A SURFACE TROUGH
EXTENDING INTO THE TROPICAL ATLC NEAR 17N55W.

ATLANTIC EAST OF 45W...
DEEP LAYERED RIDGING CONTINUES TO DOMINATE THE E ATLC WITH AXIS
ALIGNED N/S ALONG 24W. SEVERAL CUTOFF UPPER LEVEL LOWS ARE
TRAPPED BENEATH THE RIDGE AS NOTED IN WATER VAPOR IMAGERY BUT
REMAIN MOISTURE STARVED AND UNABLE TO PRODUCE SIGNIFICANT
WEATHER. FARTHER E...A DIGGING DEEP LAYERED TROUGH EXTENDS FROM
NE SPAIN S OVER W AFRICA WITH ASSOCIATED COLD FRONT TRAILING
FROM THE CENTRAL W SAHARA W TO 25N20W WHERE IT RETURNS NW AS A
STATIONARY FRONT BEYOND 32N25W. PATCHES OF LOW CLOUDS REMAIN N
OF 27N E OF 20W OVER THE CANARY ISLANDS. OVER THE TROPICAL
ATLC...THE ENTIRE ITCZ IS FAIRLY ACTIVE WITH CONVECTION BUT THE
MID/UPPER LEVEL ENVIRONMENT REMAINS UNFAVORABLE FOR TROPICAL
DEVELOPMENT.

$$
WALLACE


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