[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 141732
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT WED MAY 14 2008

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN
SECTIONS OF SOUTH AMERICA...AND THE ATLANTIC OCEAN TO THE
AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING
INFORMATION IS BASED ON SATELLITE IMAGERY...METEOROLOGICAL
ANALYSIS...WEATHER OBSERVATIONS...AND RADAR.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...TROPICAL WAVES...
WEAK TROPICAL WAVE IS ALONG 63W S OF 11N MOVING W 10-15 KT. THE
WAVE IS VERY ILL-DEFINED AND MOSTLY INLAND OVER SOUTH AMERICA.
THE MIMIC TPW ANIMATION SHOWS A FAINT MOISTURE PEAK TRAVELING
WEST N OF VENEZUELA...AND THIS FITS FAIRLY WELL WITH CONTINUITY.
SYNOPTIC SFC OBSERVATIONS OVER N VENEZUELA AND THE SRN WINDWARD
ISLANDS ARE ABOUT 1-1.5 MB LOWER THAN THIS TIME
YESTERDAY...SUGGESTIVE OF A WEAK WAVE. HOWEVER...THIS MAY BE
MORE LINKED TO THE FRONT NEAR THE GREATER  ANTILLES.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 5N9W 3N20W 2N32W 1N47W 2N52W. A NEW
TROPICAL WAVE HAS LIKELY JUST MOVED OFF THE COAST OF AFRICA
ALONG 16W OR SO...THIS WILL BE ADDED TO THE SFC MAP SOON.
SCATTERED MODERATE TO STRONG CONVECTION IS S OF 7N BETWEEN
16W-23W. SCATTERED MODERATE CONVECTION IS FROM 4N-6N BETWEEN
35W-45W...WITHIN 240 NM EITHER SIDE OF THE AXIS BETWEEN
23W-31W...AND WITHIN 180 NM N OF THE AXIS E OF 14W.

...DISCUSSION...

GULF OF MEXICO...
THE GULF LIES BETWEEN A 1023 MB HIGH OVER THE CAROLINAS AND
LOW PRES TROUGHING OVER S TEXAS AND MEXICO. THIS PATTERN IS
PRODUCING FAIRLY UNIFORM 15-20 KT SE WINDS ACROSS THE REGION.
ONLY PATCHY LOW-LEVEL CLOUDS ARE BEING DRIVEN BY THIS FLOW.
ALOFT...A LARGE UPPER HIGH IS CENTERED OVER THE YUCATAN
PENINSULA WITH ITS ASSOCIATED FLOW TRANSPORTING CIRRUS ACROSS
MUCH OF THE GULF. THE ACTIVE WEATHER LIES N OF THE ZONE OVER E
TEXAS...SE KANSAS AND N LOUISIANA. THIS WIDESPREAD TSTM ACTIVITY
IS ASSOCIATED WITH DIFFLUENT UPPER FLOW AND LOW-LEVEL LIFT ALONG
A COLD FRONT. THIS COLD FRONT WILL BE MOVING INTO THE NW GULF
TOMORROW NIGHT...INCREASING THE CHANCE OF SHOWERS. MODEL
GUIDANCE SUGGESTS THAT THIS COLD FRONT WILL MAKE IT ABOUT MIDWAY
OR SLIGHTLY FURTHER S BY LATE SAT BEFORE BECOMING STATIONARY
AND DIFFUSE.

CARIBBEAN SEA...
THE TAIL END OF A STRONG COLD FRONT FOR THIS TIME OF YEAR
EXTENDS NEAR THE WINDWARD PASSAGE...PRODUCING A FEW SHOWERS IN
ITS VICINITY. OTHERWISE...VERY TRANQUIL WEATHER PREVAILS THANKS
TO A SUBSIDENT ENVIRONMENT ASSOCIATED WITH A LARGE MID-UPPER
RIDGE CENTERED OVER THE YUCATAN PENINSULA AND UPPER TROUGHING
OVER THE E CARIB. TRADE WINDS ARE STRONGEST ACROSS THE S
CARIB...20-25 KT...AND IN THE GULF OF HONDURAS AS NOTED IN THIS
MORNINGS QSCAT PASS. LITTLE CHANGE IS EXPECTED IN THIS FLOW OVER
THE NEXT COUPLE OF DAYS. NWP MODELS ONLY SHOW A SLIGHT INCREASE
IN MOISTURE THROUGH THE END OF THE WEEK...SO MAINLY FAIR WEATHER
SHOULD CONTINUE FOR MOST OF THE REGION.

ATLANTIC OCEAN...
A LARGE 987 MB LOW PRES SYSTEM WELL N OF THE AREA OVER THE W
ATLC IS SUPPORTING A COLD FRONT WHICH ENTERS THE DISCUSSION ZONE
NEAR 32N55W AND EXTENDS SW JUST E OF THE TURKS AND CAICOS AND
INTO THE WINDWARD PASSAGE. LOW-LEVEL CONVERGENCE ALONG THE
BOUNDARY COUPLED WITH UPPER DIFFLUENT FLOW IS PRODUCING A SWATH
OF SCATTERED SHOWERS AND TSTMS WITHIN 180 NM E OF THE FRONT N OF
23N AND SCATTERED SHOWERS WITHIN 90 NM E OF THE FRONT S OF 23N.
A POST-FRONTAL TROUGH EXTENDS FROM 32N64W TO 27N72W MARKING AN
INCREASE IN NLY WINDS. THE COOL AIRMASS BEHIND THE FRONT IS
PRODUCING A SCATTERED AREA OF STRATOCUMULUS CLOUDS AND EMBEDDED
SHALLOW SHOWERS N OF 24N W OF THE FRONT.

THE REST OF THE CENTRAL AND THE E ATLC IS DOMINATED BY A MID TO
UPPER RIDGE/TROUGH PATTERN IN THE SUBTROPICS AND BROAD FLAT
RIDGING OVER THE DEEP TROPICS. LITTLE DEEP MOISTURE IS BEING
GENERATED BY THIS PATTERN IN THE SUBTROPICS BUT UPPER DIFFLUENT
FLOW IS ENHANCING CLUSTERS OF DEEP CONVECTION IN THE ITCZ. AT
THE SFC...A 1025 MB HIGH IS PARKED NEAR 29N37W PRODUCING LIGHT
WINDS ACROSS THE SUBTROPICS E OF 50W OR SO AND MAINLY 15-20 KT
NE/E TRADES ACROSS THE TROPICAL PORTION.

$$
CANGIALOSI




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