[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 091800
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT SUN OCT 09 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...SPECIAL FEATURE...

TROPICAL STORM VINCE IS NEAR 34.0N 19.2W AT 1500 UTC ABOUT 140
MILES NW OF THE MADEIRA ISLANDS MOVING NE 4 KT.  MAXIMUM
SUSTAINED WINDS ARE 45 KT GUSTING TO 55 KT WITH AN ESTIMATED
MINIMUM CENTRAL PRESSURE OF 1001 MB.  PLEASE REFER TO THE LATEST
NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23
KNHC FOR MORE DETAILS.  VINCE IS A SMALL TROPICAL CYCLONE WITH
MODERATE CONVECTION ENCIRCLING THE CENTER WITHIN 45-60
NM...INTENSIFYING RECENTLY.  AN EYE IS APPARENT ON SATELLITE
PICTURES WITH EVEN SOME HINTS OF OUTFLOW...  A SLOW MOTION TO
THE NE LOOKS LIKELY AHEAD OF A COLD FRONT WHICH WILL PROBABLY
ABSORB THE SYSTEM IN A FEW DAYS.  A PRELIMINARY EXAMINATION
SUGGESTS THIS IS THE FARTHEST EAST AND NORTH A TROPICAL CYCLONE
HAS EVER FORMED IN THE BASIN.

...TROPICAL WAVES...

E ATLC WAVE IS ALONG 28W S OF 17N MOVING AWAY FROM THE CAPE
VERDE ISLANDS W 10 KT. THIS WAVE CONTINUES TO BE NEAR THE
LEADING EDGE OF SAHARAN DUST AND IS ALSO ENHANCING SOME ITCZ
CONVECTION.

CENTRAL ATLC WAVE IS ALONG 39W S OF 16N MOVING W 10-15 KT.
THERE ISN'T MUCH OF A SATELLITE SIGNATURE WITH A TSTM NEAR
12N39W AND SOME SHOWERS WITHIN 60 NM OF THE WAVE AXIS N OF 14N.

W-CENTRAL ATLC WAVE IS ALONG 53W S OF 21N MOVING W 10 KT WITH A
1012 MB LOW NEAR 13.5N.  THIS WAVE IS THE MOST WELL-DEFINED IN
THE BASIN WITH BROAD ROTATION SEEN ON VISIBLE SATELLITE
PICTURES.  IN ADDITION SCATTERED MODERATE CONVECTION IS WITHIN
75 NM OF 11N52W AND 45 NM OF 15N52.5W.

W CARIBBEAN WAVE IS ALONG 80W S OF 18N MOVING W 10 KT.  THIS
WAVE IS NOT EASY TO FIND DUE TO THE DEEP-LAYERED WLY FLOW.
SCATTERED TSTMS ARE WITHIN 60 NM OF 11N79W.

...ITCZ...

ITCZ AXIS IS ALONG 11N16W 11N25W 8N45W 12N50W.  ISOLATED SHOWERS
AND TSTMS DOT THE AREA BETWEEN 3N-11N FROM 13W-32W.  OTHER MORE
ISOLATED ACTIVITY IS FROM 3N-10N BETWEEN 32W-48W.

...DISCUSSION...

GULF OF MEXICO...
COLD FRONT HAS NOW DISSIPATED OVER GULF WATERS WITH A WEAK
TROUGH REMAINS FROM NEAR NAPLES TO JUST N OF THE YUCATAN
PENINSULA.  SCATTERED TO OCCASIONALLY BROKEN STRATOCUMULUS
CLOUDS ARE BEHIND THE TROUGH UNTIL CLEARER SKIES N OF 28N W OF
88W.  RETURN FLOW MOISTURE IS AMASSING IN THE SW GULF S OF
BROWNSVILLE W OF 95W AND IS FORECAST TO SURGE INTO S TEXAS
TOMORROW... BRINGING WIDELY SCATTERED SHOWERS.  OTHERWISE WEAK
HIGH PRESSURE CONTROLS THE AREA WITH LIGHT WINDS... INCREASING
TOMORROW IN THE W GULF.  WSW WINDS ALOFT COVER THE REGION ALONG
WITH RELATIVELY DRY AIR.  THE NEXT SIGNIFICANT COLD FRONT MIGHT
REACH THE AREA ON FRI.

CARIBBEAN SEA...
THE AREA S OF 18N W OF 72W IS DOMINATED BY LOW-LEVEL WLY FLOW...
AN EVENT THAT HAPPENS AT MOST ONCE A YEAR.  ISOLATED
SHOWER/TSTMS ARE IN A CONVERGENT REGION BETWEEN THE WLY WINDS
AND LIGHT NLYS IN THE NW CARIBBEAN WITHIN 90NM OF 18.5N85.5W.
UPPER RIDGING LIES FROM JUST S OF CUBA TO HAITI AND THE LESSER
ANTILLES WITH ELY WINDS ALOFT.  DIVERGENCE BETWEEN THIS RIDGE
AND A HUGE UPPER LOW IN THE W ATLC IS CAUSING SCATTERED TO
NUMEROUS SHOWERS AND TSTMS FROM 13N TO PUERTO RICO BETWEEN
62W-66W.  COMPUTER MODELS SUGGEST SOME POSSIBILITY FOR TROPICAL
CYCLONE DEVELOPMENT IF THE UPPER LOW MOVES AWAY... BUT IT IS
SEEN AS UNLIKELY AT THIS TIME.

ATLANTIC OCEAN...
UPPER RIDGING EXTENDS FROM CENTRAL CUBA THRU THE NW BAHAMAS TO
31N75W WITH SCATTERED TSTMS OVER THE BAHAMAS NEAR AND SE OF
ANDROS ISLAND TO JUST NW OF HAITI.  OTHERWISE A LARGE POWERFUL
UPPER LOW IS NEAR 25.5N63W WITH A CYCLONIC WIND ENVELOPE OF
ABOUT 6 DEGREES.  STRONG TSTMS ARE WITHIN 120 NM OF 19N60W IN A
DIVERGENT REGION OF THE UPPER LOW.  THE REMNANTS OF SUBTROPICAL
DEPRESSION 22 ARE NEAR 29N64.5W AS A 1012 MB LOW WITH AN
ISOLATED MODERATE CLUSTER OF TSTMS NEAR 29N65.5W.  THE UPPER LOW
IS MOVING WESTWARD BENEATH A STRONG MID-LATITUDE RIDGE IN THE W
ATLC...WHICH IS FORECAST TO BREAK DOWN IN A COUPLE DAYS AND
ALLOW THE UPPER LOW TO EVENTUALLY MOVE MORE TO THE NW AND N EAST
OF THE USA.  UPPER HIGH LIES NEAR 15N45W WITH HIGH LEVEL
MOISTURE ROTATING AROUND THE N SIDE OF THE HIGH FROM 15N-28N
BETWEEN 35W-60W.  ISOLATED SHOWERS/TSTMS ARE ALSO FROM 22N-27N
BETWEEN 50W-58W.  IN THE E ATLC... AN UPPER TROUGH RUNS FROM
NEAR VINCE TO 15N35W WITH DRY AIR PLENTIFUL BETWEEN 20N-30N E OF
30W.  UPPER DIVERGENCE IS MODEST OVER THE ITCZ TODAY.. PRODUCING
A TON OF SMALL SHOWERS/TSTMS S OF 11N E OF 40W.

$$
BLAKE

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