[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 290557
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT SAT OCT 29 2005

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHEASTERN 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0445 UTC.

...SPECIAL FEATURE...

TROPICAL STORM BETA IS CENTERED NEAR 13.6N 81.5W...NEAR THE
ISLAND OF PROVIDENCIA...AT 29/0300 UTC MOVING NNW 4 KT.
ESTIMATED MINIMUM CENTRAL PRESSURE IS 989 MB. MAXIMUM SUSTAINED
WIND SPEED IS 65 KT WITH GUSTS TO 80 KT. SEE LATEST NHC
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC
AND THE PUBLIC ADVISORY UNDER HEADERS MIATCPAT1/WTNT31 FOR MORE
DETAILS. BETA HAS MAINTAINED ITS INTENSITY FOR MUCH OF THE DAY
AND THE CONVECTIVE PATTERN REFLECTS THIS WITH VERY LITTLE CHANGE
IN THE STRUCTURE. THE TSTM ACTIVITY COMES AND GOES IN BURSTS
WITH THE STRONGEST CONVECTION ISOLATED NEAR THE CENTER. ONE
PRIMARY SPIRAL BAND IS NOTED EXTENDING N AND E...MELDING INTO
ADDITIONAL CONVECTION WHICH HAS FORMED NEAR THE CAYMAN ISLANDS.
NUMEROUS MODERATE/ STRONG CONVECTION IS FROM 12N-15N BETWEEN
80W-82W. TEN TO FIFTEEN INCHES OF RAIN ARE EXPECTED OVER PARTS
OF NICARAGUA...NE HONDURAS...AND THE ISLANDS OF SAN ANDRES AND
PROVIDENCIA DUE TO THE SLOW N/NW MOVEMENT OF BETA OVER THE NEXT
FEW DAYS.

...TROPICAL WAVES...

CENTRAL ATLANTIC TROPICAL WAVE ALONG 45W S OF 19N MOVING W 10-15
KT. A WELL-DEFINED AND ALMOST CIRCULAR LOW-LEVEL CIRCULATION IS
ASSOCIATED WITH THE WAVE.  HOWEVER, CONVECTION REMAINS LIMITED
AND DISPLACED WEST WITH SCATTERED MODERATE CONVECTION IN A SMALL
AREA W OF THE WAVE FROM 12N-16N BETWEEN 44W-49W.

EAST/CENTRAL CARIBBEAN TROPICAL WAVE ROUGHLY ALONG 67W HAS BEEN
REPOSITIONED ALONG 70W S OF 21N MOVING W 10-15 KT.
REPOSITIONING OF THE WAVE IS BASED ON SATELLITE, SURFACE OBS AND
UW-CIMSS. WIDELY SCATTERED MODERATE CONVECTION EXTENDS FROM
11N-19N BETWEEN 70W-74W STRETCHING FROM SOUTHERN PUERTO RICO
ACROSS HISPANIOLA.


...ITCZ...

ITCZ AXIS IS ALONG 12N14W 7N20W 4N30W 9N39W. SCATTERED
MODERATE/STRONG CONVECTION PUSHING OFF THE COAST OF AFRICA FROM
GUINEA S TO LIBERIA. WIDELY SCATTERED MODERATE FROM EQ-20N
BETWEEN 11W-26W. SCATTERED MODERATE FROM 8N-13N BETWEEN 53W-60W
PARTLY DUE TO AN UPPER LOW NEAR 9N60W IS BRUSHING ACROSS
TRINIDAD...NE VENEZUELA...N GUYANA...N SURINAME...AND N FRENCH
GUIANA.

...DISCUSSION...

GULF OF MEXICO...
DRY AIR CONTINUES TO DOMINATE THE GULF OF MEXICO...VIA A LARGE
MID-LATITUDE UPPER TROUGH EXTENDING FROM NEW ENGLAND TO THE SW
GULF. AT THE SURFACE A DISORGANIZED BAND OF LOW/MID LEVEL CLOUDS
EXTENDS FROM NEAR CAPE CANAVERAL FLORIDA SW TO VERACRUZ MEXICO
AND IS LIKELY THE LEADING EDGE OF A SECONDARY SURGE OF THE DRIER
AIR.  LITTLE CHANGE IS EXPECTED IN THE OVERALL PATTERN THROUGH
THE REST OF WEEKEND WITH DEEP TROPICAL MOISTURE STILL TRAPPED
JUST EAST OF THE AREA UNTIL AT LEAST EARLY NEXT WEEK. A COLD
FRONT IS EXPECTED TO MOVE OFF THE TEXAS COAST TUE MORNING WITH
INCREASING MOISTURE OVER THE E GULF AHEAD OF THE BOUNDARY.

CARIBBEAN...
T.S. BETA IS STILL LOCATED OFF THE COAST OF NICARAGUA AND IS
SLOWLY DRIFTING N PAST PROVIDENCIA ISLAND. SEE SPECIAL FEATURES
FOR FURTHER DISCUSSION. A LARGE UPPER LEVEL HIGH CENTERED JUST S
OF HISPANIOLA NEAR 17N73W CONTINUES TO INTERACT WITH THE
TROPICAL WAVE OVER THE CNTRL CARIBBEAN TO PRODUCE A BROAD AREA
OF SCATTERED MODERATE CONVECTION EXTENDING S OF HAITI TO NRN
COLOMBIA AND VENEZUELA. THE WAVE IS USHERING IN DRIER AIR OVER
THE E CARIBBEAN AND IS GETTING SOME HELP FROM MODERATE
SUBSIDENCE ON THE W SIDE OF AN UPPER LOW LOCATED N OF GUYANA
NEAR 11N60W. THIS IS CONTINUING TO PRODUCING TRANQUIL WEATHER
FROM TRINIDAD NWD ACROSS THE ENTIRE LESSER ANTILLES CHAIN TO THE
VIRGIN ISLANDS. ELSEWHERE...MOISTURE FROM BETA CONTINUES TO BE
DRAWN NWD BY THE SUBTROPICAL JET AND THERE IS AMPLE LOW-LEVEL
CONVERGENCE TO PRODUCE SCATTERED MODERATE/ISOLATED STRONG
CONVECTION FROM 16N-22N BETWEEN 78W-82W EXTENDING ACROSS THE
CAYMAN ISLANDS AND CNTRL CUBA. DRIER WEATHER EXTENDS W OF 85W TO
THE YUCATAN PENINSULA DUE TO SUBSIDENCE ASSOCIATED WITH THE GULF
OF MEXICO UPPER TROUGH.

ATLANTIC...
AN UPPER LEVEL SHORTWAVE EXTENDS FROM THE COAST OF NORTH
CAROLINA TO CENTRAL FLORIDA AND IS EMBEDDED WITHIN A MUCH LARGER
UPPER LONG WAVE TROUGH OVER THE EASTERN UNITED STATES.  A 1012
MB SURFACE LOW IS LOCATED OFF THE NORTH CAROLINA COAST NEAR
34N72W. A COLD FRONT EXTENDS S OF THE LOW TO 33N72W TO 24N76W
NEAR S OF GREAT ABACO ISLAND IN THE BAHAMAS. WIDELY SCATTERED
SHOWERS EXTEND FROM 29N-23N BETWEEN 71W-76W WITHIN 100 NM OF THE
FRONT. ELSEWHERE...A VIGOROUS UPPER LEVEL LOW IS LOCATED ABOUT
160 NM ENE OF TRINIDAD NEAR 11N60W WITH AN INVERTED TROUGH
EXTENDING N TO 23N59W...MOVING QUICKLY W TOWARDS THE WINDWARD
ISLANDS AND EXPECTED TO CROSS INTO THE E CARIBBEAN LATER TODAY.
THE LOW IS PRODUCING DRY WEATHER ACROSS THE LESSER ANTILLES BUT
SCATTERED MODERATE CONVECTION CONTINUES TO PUSH TO THE
WEST...FROM 9N-12N BETWEEN 53W-60W. A LARGE UPPER HIGH CONTINUES
TO DOMINATE THE CENTRAL ATLANTIC NEAR 26N45W AND IS PUSHING THE
SUBTROPICAL JET WELL N OF THE AREA...ALLOWING A SURFACE RIDGE TO
BUILD ALONG 27N. A NEARLY STATIONARY UPPER TROUGH LIES E OF THE
HIGH FROM MOROCCO SW TO THE CAPE VERDE ISLANDS.  FARTHER S...AN
ELONGATED UPPER LOW IS CENTERED NEAR 10N34W AND IS INDUCING
SLIGHT UPPER DIFFLUENCE TO ITS E.

$$
JP/JR


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