[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 171744
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST MON 17 JAN 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.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 3N1W 4N13W 1N27W 2N40W EQ49W.
ISOLATED SHOWERS S OF 4N BETWEEN 14W-23W.  ISOLATED TSTMS WITHIN
45 NM OF AXIS BETWEEN 27W-34W.

...DISCUSSION...

GULF OF MEXICO...W ATLANTIC AND CARIBBEAN...
STRONG COLD FRONT ENTERS THE W ATLC NEAR 31N68W SW ACROSS THE SE
BAHAMAS THRU THE WINDWARD PASSAGE INTO THE CARIBBEAN SEA JUST E
OF JAMAICA CONTINUING SSW TO NEAR THE COSTA RICA/PANAMA BORDER.
WIDELY SCATTERED SHOWERS ARE WITHIN 60 NM OF THE FRONT S OF 27N
WITH WIDELY SCATTERED SHOWERS AND A FEW TSTMS WITHIN 90 NM ALONG
AND AHEAD OF THE FRONT N OF 27N.  THE HEAVIER RAINS ARE CAUSED
BY A SHORTWAVE PASSING 71W N OF THE BAHAMAS WITH ENHANCED
DIVERGENCE/LIFT TO THE E AND NE OF THE SYSTEM.  BROAD MID/UPPER
TROUGHING PERSISTS IN THE W ATLC ALONG ABOUT 75W N OF 25N WITH
INDIVIDUAL SHORTWAVES OCCASIONALLY SHARPENING THE BASE OF
TROUGH.  BEHIND THE FRONT...SCATTERED TO BROKEN LOW CLOUDS AND
ISOLATED SHOWERS COVER THE NW CARIBBEAN AND W GULF OF MEXICO
WITH THICKER CLOUDS OVER THE W ATLC.  THE ONLY AREA IS THAT IS
MOSTLY CLOUD-FREE IS THE NE GULF WHERE THE COOL DRY CONTINENTAL
AIR HASN'T HAD ENOUGH TIME TO WARM AND MOISTEN UP TO PRODUCE THE
LOW CLOUDS SEEN IN THE REST OF THE REGION.   NLY WINDS OVER THE
HIGH TERRAIN OF CENTRAL AMERICA FROM HONDURAS NW THRU CENTRAL
MEXICO ARE CAUSING OVERCAST CONDITIONS ALONG WITH SHOWERS IN
HIGH ELEVATIONS.  OTHERWISE IN THE E CARIBBEAN... A VERY
PLEASANT DAY IS ONGOING WITH REDUCED TRADEWIND SHOWERS AND
GENERALLY SUNNY SKIES.  MODERATE/STRONG SUBSIDENCE COVERS THE
ENTIRE AREA W OF THE COLD FRONT WITH GENERALLY ZONAL FLOW ALOFT
IN THE CARIBBEAN AND SOME WEAK TROUGHING OVER THE LEEWARD
ISLANDS.  MOISTURE FROM THE COLD FRONT SHOULD ENTER THE PUERTO
RICO AREA BY WED WITH ENHANCED OROGRAPHIC CLOUDS/RAIN CHANCES.

CENTRAL AND EAST ATLANTIC...
WEAKENING MID/UPPER LEVEL TROUGH IS ORIENTED NW/SE ACROSS THE
CENTRAL ATLC THROUGH 32N57W TO 22N51W AND IS PRODUCING MID/UPPER
LEVEL CLOUDS.  A LARGE HIGH NEAR 37N40W IS RIDGING DOWN INTO THE
AREA AND COVERING THE REST OF THE CENTRAL ATLC WITH STRONG
SUBSIDENCE/DRY AIR ALOFT.  SURFACE HIGH EDGES INTO THE AREA NEAR
32N52W TO 27N65W THOUGH TRADES ARE REDUCED FROM LAST WEEK.  THE
DEEP TROPICS HAS A STRONG SUBTROPICAL JET OVERHEAD WITH CIMSS
WINDS INDICATING MAX SPEEDS <100 KT AND IS SENDING A LARGE PLUME
OF MOISTURE IN THE MID/UPPER LEVELS SPEEDING ACROSS THE ATLC
FROM NE S AMERICA THRU THE CAPE VERDES TO W AFRICA.  NEARLY
OVERCAST MULTI-LAYERED CLOUDS ARE PRESENT FROM 8N-18N FROM THE
CAPE VERDES TO 56W.  WIDELY SCATTERED MODERATE CONVECTION IS
WITHIN 60 NM OF 7.5N56W... WITH LOW-LEVEL CONVERGENCE AND WEAK
UPPER TROUGHING SUPPORTING THE TSTMS.  IN THE E ATLC... 1004 MB
GALE-FORCE LOW IS NEAR 27N22W MOVING WSW 5-10 KT.  LOW IS PAST
ITS PRIME WITH AN OCCLUDED FRONT FROM 28N25W 30N20W 28N18W
BECOMING STATIONARY TO 24N17W THEN 21N19W STILL A COLD FRONT TO
18N30W.  THESE FRONTAL FEATURES ARE BEGINNING TO WEAKEN AS THE
LOW IS CUT-OFF FROM ANY BAROCLINIC BOUNDARIES AND SLOWLY SPINS
DOWN.  WIDELY SCATTERED SHOWERS AND TSTMS ARE N OF 26N E OF 25W
WITH BROKEN LOW CLOUDS/ISOLATED SHOWERS N OF 22N E OF 45W.  A
RARE WINTER RAIN EVENT COULD OCCUR TOMORROW IN THE CAPE VERDES
AS THE COLD FRONT WEAKENS OVER THE ISLANDS AND PLENTIFUL
MID/UPPER MOISTURE CONTINUES WITH THE NEARBY SUBTROPICAL JET
PROVIDING LIFT/DIVERGENCE.

$$
BLAKE

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