[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 062322
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST SUN 06 FEB 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2245 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 5N6W 3N14W 2N30W 4N40W 1N53W.
CLUSTER OF STRONG CONVECTION IS PROPAGATING WESTWARD S OF 6N
BETWEEN 3W-6W.  ISOLATED MODERATE WITHIN 60 NM OF AXIS BETWEEN
10W-35W.

...DISCUSSION...

MEXICO AND GULF OF MEXICO...
A BROAD AND DEEP LONGWAVE MID/UPPER TROF IS LOCATED OVER THE
WESTERN U.S. AND PACIFIC COAST OF MEXICO WITH SEVERAL SHORTWAVE
DISTURBANCES MOVING UP THE E SIDE THROUGH MEXICO AND THE CNTRL
PLAINS. THE SUBTROPICAL JET EXTENDS ACROSS N MEXICO INTO THE
CENTRAL PLAINS WITH PLENTIFUL HIGH CLOUDS E OF 105W OVER A GOOD
PORTION OF THE EASTERN 2/3RDS OF THE USA.  THESE CLOUDS ARE
RIDING UP THE W SIDE OF A STRONG UPPER RIDGE EXTENDING FROM THE
YUCATAN CHANNEL NNE THRU GEORGIA WITH ISOLATED SHOWERS OVER
COASTAL TEXAS WATERS.  SCATTERED TO BROKEN STRATOCUMULUS ARE ALSO
MOVING W TO NW OVER THE GULF WATERS WITHIN THE SLY RETURN FLOW.
A WEAK COLD FRONT IS EXPECTED TO STALL AND DISSIPATE ALONG THE
TX/LA COAST LATE MON AND TUE INCREASING RAIN CHANCES...AND THEN
A STRONGER SECOND COLD FRONT WILL PUSH INTO THE GULF LATE WED
AND THU BUT WITH A MORE LIMITED MOISTURE SUPPLY.

WEST/CENTRAL ATLANTIC...
1002 MB OCCLUDED LOW...THE SECOND IN A SERIES THAT HAS LED TO AN
UNUSUALLY DEEP MEAN TROUGH IN THE W-CENTRAL ATLC FOR OVER A
WEEK...IS CURRENTLY LOCATED SE OF BERMUDA NEAR 29N61W. THE
OCCLUDED FRONT CURVES N THEN E AROUND THE LOW ALONG 30N62W
31N60W 31N54W 28N52W 25N54W THEN CONTINUES AS A DISSIPATING COLD
FRONT TO THE LEEWARD ISLANDS NEAR BARBUDA. LOW IS DEEP-LAYERED
AND BROAD CYCLONIC FLOW IN THE MID/UPPER LEVELS EXTENDS ACROSS
THE ENTIRE W/CNTRL ATLC...GENERALLY W OF 50W. BROAD DIVERGENCE
TO THE SE OF THE LOW IS ENHANCING BANDS ALONG LOW-LEVEL
CONVERGENCE BANDS WITH SCATTERED MODERATE CONVECTION BETWEEN
45W-51W FROM 20N-31N.  SURFACE TROF RUNS FROM 23N48W TO JUST S
OF GUADELOUPE WITH SOME THE STRONGEST CELLS FOCUSED NEAR THE NE
PART OF THE TROF. STRONG SUBSIDENCE IS WRAPPING AROUND THE
SOUTHERN FLANK OF THE LOW WITH COLD AIR ALOFT SUPPORTING
ISOLATED SHOWERS/TSTMS IN THE VICINITY OF THE LOW N OF 26N
BETWEEN 56W-64W.  THE LOW WILL HANG AROUND FOR ANOTHER 48 HRS OR
SO...BUT SHOULD BEGIN TO LIFT N OF THE AREA BY LATE WED.  A MEAN
TROUGH LOOKS LIKELY BETWEEN 50W-60W AFTERWARDS BUT THE MAIN
AMPLITUDE SHOULD SHIFT INTO THE MID-LATITUDES.

CARIBBEAN...
THE WEAKENING COLD FRONT ASSOCIATED WITH THE LARGE OCCLUDED LOW
OVER THE W ATLC HAS PROGRESSED SWD THRU PUERTO RICO TO THE
LEEWARD ISLANDS NEAR BARBUDA. RADAR IMAGERY FROM SAN JUAN
INDICATES THERE ARE ISOLATED LIGHT SHOWERS IN THE AREA WITH THE
90 NM WIDE FRONTAL CLOUD BAND OUT OF RADAR RANGE. AN OLD FRONTAL
TROF ALSO EXTENDS SE OF THE FRONT FROM JUST NE OF THE ABC
ISLANDS TO DOMINICA BUT THE MID/UPPER LEVELS ARE TOO DRY TO
SUPPORT ANY DEEP CONVECTION WITH ISOLATED SHOWER. A STRONG UPPER
RIDGE IS LOCATED OVER THE CNTRL AMERICAN LANDMASS AND THE FLOW
TO THE E OF THIS FEATURE IS CONVERGING WITH THE BROAD CYCLONIC
FLOW OVER THE W ATLC...PRODUCING A SWATH OF STRONG SUBSIDENCE
E/W ACROSS THE ENTIRE CARIBBEAN. ELSEWHERE...PATCHY LOW CLOUDS
EXTEND ACROSS THE NW CARIBBEAN WITH A WEAK LINE OF SHOWERS
MOVING SWWD TO THE GULF OF HONDURAS.  SIGNIFICANT RAIN CHANCES
THRU MIDWEEK LOOK TO BE CONFINED TO THE SE CARIBBEAN WHERE
DEEPER MOISTURE AND RESIDUAL CONVERGENCE BOUNDARIES RESIDE.

EAST ATLANTIC...
STRONG SFC RIDGE CONTROLS THE AREA E OF 45W AND IS ADVECTING
FEW/BROKEN STRATOCUMULUS OVER THE E ATLC WATERS. A STRONG RIDGE
IS ALSO LOCATED IN THE UPPER LEVELS ALONG 37W/38W AND IS KEEPING
VIRTUALLY ALL CONVECTION ASSOCIATED WITH THE W ATLC LOW W OF
40W. FARTHER E...A LARGE UPPER LEVEL LONGWAVE TROF EXTENDS SW OF
PORTUGAL/SPAIN AND REACHES ACROSS THE CANARY ISLANDS TO THE CAPE
VERDES. HOWEVER...THERE IS LITTLE ATMOSPHERIC MOISTURE TO WORK
WITH WITH ONLY ISOLATED COLD-AIR SHOWERS OVER THE CANARY
ISLANDS.  DESPITE AMPLE UPPER-LEVEL SUPPORT.. ITCZ CONVECTION IS
RATHER LIMITED WITH SOME DRY SAHARAN AIR PROBABLY LIMITING THE
TSTM ACTIVITY.

$$
BLAKE


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