[Tropical] Tropical Weather Discussion

Tue May 31 00:41:47 CDT 2005

AXNT20 KNHC 310541
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT TUE MAY 31 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
0515 UTC.

...TROPICAL WAVES...

CENTRAL ATLC TROPICAL WAVE ALONG 43W S OF 12N MOVING W 15-20
KT. THE WAVE IS EMBEDDED WITHIN A LARGE SWATH OF AFRICAN DUST.
AS SUCH...THE SATELLITE SIGNATURE IS POOR WITH ONLY ISOLATED
CELLS OF DEEP CONVECTION S OF 10N. POSITION BASED PRIMARILY ON
EXTRAPOLATION.

TROPICAL WAVE OVER THE CENTRAL CARIBBEAN ALONG 72W/73W S OF 20N
MOVING W 15-20 KT. THE WAVE IS TRIGGERING SCATTERED SHOWERS/
THUNDERSTORMS INLAND OVER SOUTH AMERICA.

TROPICAL WAVE OVER CENTRAL AMERICA ALONG 85W/86W S OF 18N MOVING
W 10 KT. MOST OF THE ENERGY WITH THIS WAVE IS S OF THE AREA OVER
THE E PACIFIC. ISOLATED SHOWERS ARE WITHIN 150 NM W OF THE WAVE
AXIS N OF HONDURAS.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 10N14W 5N24W 6N32W 5N45W 6N60W.
LARGE CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE
WITHIN 200 NM EITHER SIDE OF ITCZ AXIS FROM 18W-31W. CLUSTERS OF
SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 225 NM
OF 6N FROM 31W-45W AND WITHIN 120 NM OF THE AXIS E OF 45W TO
INLAND OVER SOUTH AMERICA. SCATTERED/NUMEROUS STRONG CONVECTION
IS INLAND OVER GUINEA AND SIERRA LEONE MOVING TOWARD THE COAST
AND BE OFFSHORE OVER THE NEXT FEW HOURS.

...DISCUSSION...

GULF OF MEXICO...
A FAR MORE ACTIVE PATTERN CONTINUES TONIGHT AS A SHARP MID/UPPER
LEVEL TROUGH COVERS THE W GULF. STRONG DIFFLUENCE E OF THE
TROUGH IS CURRENTLY SUPPORTING AN NE MOVING CONVECTIVE COMPLEX
OVER THE CENTRAL GULF FROM THE E FLORIDA PANHANDLE TO OVER THE
YUCATAN PENINSULA AND E BAY OF CAMPECHE. MULTIPLE SQUALL LINES
ARE OBSERVED ON INFRARED SATELLITE IMAGERY WITH SCATTERED
MODERATE/ STRONG CONVECTION CURRENTLY WITHIN 225 NM E OF A
SURFACE TROUGH FROM THE FLORIDA PANHANDLE NEAR 31N85W SW TO A
1005 MB LOW NEAR 25N89W TO OVER S MEXICO AND A 1002 MB LOW NEAR
18N94W. THIS COMPLEX WILL CONTINUE TO MOVE E DURING THE EARLY
MORNING HOURS PRODUCING PERIODS OF SQUALLS ACCOMPANIED BY STRONG
WINDS AND HEAVY RAINFALL. FURTHER E...DEEP-LAYERED SW FLOW IS
PRODUCING MOISTURE ADVECTION OVER THE E GULF ACROSS AND FLORIDA.
THIS FLOW/MOISTURE WILL CONTINUE TO INCREASE THROUGH TODAY AS
THE UPPER TROUGH PUSHES SLOWLY E REACHING APPROXIMATELY 90W BY
TONIGHT WHERE IT WILL STALL ON WED. THIS WILL PRODUCE A VERY
UNSTABLE ENVIRONMENT OVER THE E HALF OF THE GULF AND FLORIDA
SETTING THE STAGE FOR THE DEVELOPMENT OF WIDESPREAD SHOWERS AND
THUNDERSTORMS. WHILE CONVECTION WILL BE POSSIBLE AT ANY TIME
ESPECIALLY NEAR AND TO THE E OF THE UPPER TROUGH...ACTIVITY
SHOULD BE MOST NUMEROUS OVER THE FLORIDA PENINSULA DURING THE
PEAK HEATING HOURS. AT THE SURFACE...IN ADDITION TO THE
LOW/SURFACE TROUGH ACROSS THE GULF...A STATIONARY FRONT IS
MEANDERING ALONG THE N GULF COAST INLAND ACROSS THE SE UNITED
STATES FROM A 1012 MB LOW CENTERED OFF THE GEORGIA/SOUTH
CAROLINA COAST AND REMAIN IN THE GENERAL VICINITY THROUGH WED.
MEANWHILE...SUBTROPICAL RIDGE WILL BECOME BETTER ESTABLISHED
ALONG 24N/25N.

CARIBBEAN...
A WELL-DEFINED MID/UPPER LEVEL HIGH IS CENTERED OVER THE W
CARIBBEAN ALONG THE COAST OF NICARAGUA NEAR 13N84W WITH A
MID/UPPER LEVEL TROUGH EXTENDING FROM THE CENTRAL ATLC INTO THE
E CARIBBEAN E OF 73W. THIS PATTERN CONTINUES TO PRODUCE
SUBSIDENCE AND DRY/STABLE AIR ALOFT OVER THE CENTRAL TO W
CARIBBEAN FROM 73W-83W. THIS AIRMASS CONTINUES TO SUPPRESS
CONVECTIVE ACTIVITY OVER THE AREA. FURTHER W...DEEP-LAYERED S
FLOW AND ASSOCIATED MOISTURE ADVECTION AHEAD OF A TROUGH OVER
THE W GULF IS PRODUCING ENHANCED AFTERNOON SHOWERS/THUNDERSTORMS
OVER S MEXICO AND THE YUCATAN PENINSULA. EXPECT UNSTABLE
CONDITIONS WITH POSSIBLE SHOWERS/THUNDERSTORMS TO CONTINUE OVER
THIS AREA AS THE GULF TROUGH AMPLIFIES SE DURING THE NEXT 24
HOURS. OVER THE E CARIBBEAN...THE MAIN WEATHER FEATURE IS A
SECONDARY SURGE OF AFRICAN DUST MOVING ACROSS THE AREA E OF 70W.
THE PLUME EXTENDS ESSENTIALLY ALL THE WAY FROM W AFRICA TO
CENTRAL AMERICA SO EXPECT HAZY CONDITIONS TO CONTINUE FOR THE
NEXT SEVERAL DAYS.

ATLANTIC...
UPPER LEVEL RIDGING HAS AMPLIFIED FROM THE W CARIBBEAN N ALONG
80W ACROSS FLORIDA AND THE BAHAMAS WITH DOWNSTREAM TROUGHING
FROM THE CENTRAL ATLC EXTENDING THROUGH 32N53W SSW ACROSS THE N
LEEWARD ISLANDS TO THE COAST OF VENEZUELA NEAR THE ABC ISLANDS.
THIS PATTERN IS PRODUCING INCREASING DEEP-LAYERED MOISTURE AND
FAVORING SHOWERS/THUNDERSTORMS OVER THE BAHAMAS TO CUBA W OF
76W. OVER OPEN WATER...AN OLD REMNANT FRONTAL TROUGH CONTINUES
TO GENERATE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM
21N-26N BETWEEN 57W-67W. MAIN FOCUS FOR CONVECTION OVER THE NEXT
COUPLE OF DAYS WILL BE OVER THE W ATLC AS THE MID/UPPER LEVEL
TROUGH OVER THE GULF PUSHES E TO OVER THE CENTRAL/EAST GULF.
THIS PATTERN WILL PRODUCE A VERY UNSTABLE ENVIRONMENT WITH
POSSIBLE SHOWERS/THUNDERSTORMS OVER THE FAR NW PORTION OF THE
AREA ON TUE AND WED GENERALLY NW OF A LINE FROM W CUBA TO
BERMUDA. OVER THE CENTRAL/EASTERN ATLC...BROAD...BUT WEAK...
DEEP LAYERED TROUGH COVERS THE AREA FROM 27W-60W WITH AN
EMBEDDED UPPER LOW NEAR 19N44W. AT THE SURFACE...A COLD FRONT
ENTERS THE AREA NEAR 32N48W EXTENDING S TO 30N51W THEN W TO
30N56W WHERE IT CONTINUES AS A STATIONARY FRONT ACROSS THE W
ATLC TO THE 1012 MB LOW OFF THE SE UNITED STATES COAST. A
SURFACE TROUGH REMAINS IN THE CENTRAL ATLC EXTENDING THROUGH
32N43W SSW TO 22N50W. OVER THE FAR E ATLC...RIDGING EXTENDS FROM
INLAND OVER W AFRICA NW TO JUST W OF THE CANARY ISLANDS. THE
UPPER TROUGH PATTERN IS EXPECTED TO SLOWLY BREAKDOWN DURING THE
COUPLE OF DAYS AS A WELL-DEFINED MID/UPPER LEVEL RIDGE DEVELOPS
FROM AFRICA W WITH AN UPPER HIGH DEVELOPING ALONG 20W ON WED. AT
THE SURFACE...WEAK TROUGHING OVER THE CENTRAL ATLC CONTINUES TO
PARTIALLY DISRUPT THE SUBTROPICAL RIDGE. CURRENTLY...MEAN RIDGE
AXIS CURRENTLY EXTENDS FROM A 1035 MB JUST E OF OF THE AZORES SW
ALONG 32N32W TO 24N40W BRIDGING ACROSS THE DEEP LAYERED TROUGH
OF THE CENTRAL ATLC W TO NEAR 25N72W. S OF THE RIDGE...MODERATE
TO STRONG TRADES PREVAIL WITH AN EXPANSIVE PLUME OF AFRICAN DUST
SPANNING THE ENTIRE LENGTH OF THE ATLC AND CARIBBEAN...GENERALLY
S OF 25N TO THE ITCZ.

$$
WALLACE

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