[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 301043
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT SAT MAY 30 2009

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1015 UTC.

...TROPICAL WAVES...
A TROPICAL WAVE IS ALONG 50W S OF 9N MOVING W 15-20 KT. TOTAL
PRECIPITABLE WATER PRODUCT FROM CIMSS INDICATES THAT THIS WAVE
COINCIDES WITH AN AREA OF MAXIMUM DEEP LAYER MOISTURE THAT IS
EXHIBITING CYCLONIC TURNING OF THE WIND NEAR THE WAVE AXIS.
SCATTERED MODERATE CONVECTION IS S OF 6N BETWEEN 46W-53W.

...THE ITCZ...
THE ITCZ AXIS IS CENTERED ALONG 8N12W 5N23W CROSSING THE EQUATOR
NEAR 39W AND INTO NE BRAZIL NEAR 1S46W. SCATTERED MODERATE TO
STRONG CONVECTION IS S OF 6N E OF 5W. SCATTERED MODERATE
CONVECTION IS S OF 3N BETWEEN 35W-45W.

...DISCUSSION...

GULF OF MEXICO...
A COLD FRONT IS PRESENT ACROSS THE ERN GULF AND AT 30/0900 UTC
EXTENDS FROM NEAR JACKSONVILLE TO CLEARWATER FLORIDA AND INTO
THE GULF ALONG 27N84W TO 25N92W. ALSO...A SURFACE TROUGH EXTENDS
FROM 25N88W INTO THE ERN BAY OF CAMPECHE NEAR 19N92W. LOW LEVEL
CONVERGENCE AND INSTABILITY ALONG AND E OF THE BOUNDARY IS
RESULTING IN SCATTERED SHOWERS AND ISOLATED TSTMS WITHIN 60 NM
OF THE COLD FRONT ACROSS THE SE GULF AND ACROSS INTERIOR
PORTIONS OF THE SRN FLORIDA PENINSULA S OF 27N. ALL OF THIS
ACTIVITY IS FURTHER SUPPORTED BY UPPER LEVEL DIFFLUENCE IN MOIST
ZONAL WLY UPPER LEVEL FLOW. ACROSS THE N GULF AND N OF THE COLD
FRONT...GENERALLY FAIR WEATHER AND LIGHT NELY WINDS ARE OBSERVED
WHERE STABLE ATMOSPHERIC CONDITIONS AND A SURFACE RIDGE ARE
PRESENT. A FEW EWD MOVING SCATTERED TO BROKEN HIGH LEVEL
CONVECTIVE DEBRIS CLOUDS ARE ACROSS THE WRN GULF FROM REMAINING
SHOWERS ACROSS INLAND ERN MEXICO THIS MORNING.

CARIBBEAN SEA...
DEEP LAYER DRY AIR AND SUBSIDENCE IN NWLY FLOW ALOFT...ALONG
WITH MID-LEVEL DRY SAHARAN AIR...ARE RESULTING IN GENERALLY FAIR
WEATHER ACROSS MUCH OF THE CARIBBEAN. FRESH TO STRONG TRADE
WINDS ARE OCCURRING ACROSS THE CARIBBEAN AND ARE EXPECTED TO
PERSIST THROUGH THE NEXT SEVERAL DAYS. MAINLY 15 TO 20 KT SHIP
AND BUOY OBSERVATIONS ARE ACROSS THE CENTRAL AND WRN CARIBBEAN
WITH GLOBAL MODEL DATA DEPICTING THE STRONGEST WINDS...UP TO 25
KT...NEAR THE NRN COASTS OF COLOMBIA AND VENEZUELA. ALSO...
ATMOSPHERIC INSTABILITY ASSOCIATED WITH AN UPPER LEVEL TROUGH
OVER THE NE CARIBBEAN IS SUPPORTING ISOLATED SHOWERS OVER THE
ERN CARIBBEAN E OF 68W.

ATLANTIC OCEAN...
UPPER LEVEL DIFFLUENCE AND DEEP LAYER MOISTURE ASSOCIATED WITH
AN UPPER LEVEL RIDGE OVER THE SW NORTH ATLC AND A UPPER LEVEL
TROUGH OVER THE ERN CONUS ARE SUPPORTING SCATTERED SHOWERS AND
TSTMS ALONG A COLD FRONT THAT IS DRAPED ALONG THE E COAST FROM
NORTH CAROLINA TO JACKSONVILLE FLORIDA. A PRE-FRONTAL TROUGH IS
ANALYZED AT 30/0900 UTC E OF THE FRONT EXTENDING FROM 33N77W TO
29N78W. THE CONVECTIVE ACTIVITY IS LOCATED WITHIN 90 NM E OF THE
TROUGH AND EXTENDS S TO COVER THE AREA FROM 22N-29N W OF 71W...
INCLUDING THE NW AND CENTRAL BAHAMAS AND THE STRAITS OF FLORIDA.
ALSO...UPPER LEVEL DIVERGENCE AND DEEP LAYER MOISTURE TO THE NW
OF AN UPPER LEVEL RIDGE AXIS EXTENDING FROM 30N60W TO 20N50W ARE
SUPPORTING SCATTERED SHOWERS FROM 26N-33N BETWEEN 60W-66W. A
SURFACE TROUGH IS ANALYZED NE OF THE LEEWARD ISLANDS AND EXTENDS
FROM 25N55W TO 18N57W. SCATTERED SHOWERS ARE OBSERVED FROM
18N-26N BETWEEN 52W-58W. FARTHER TO THE E...AN UPPER LEVEL
TROUGH AXIS ALONG 26N23W 21N35W 20N47W IS ASSOCIATED WITH A COLD
FRONT EXTENDING INTO THE DISCUSSION AREA NEAR 32N26W ALONG
29N30W TO 27N34W CONTINUING WWD AS A STATIONARY FRONT TO 26N44W.
LOW LEVEL CONVERGENCE IS SUPPORTING SCATTERED SHOWERS WITHIN 60
NM EITHER SIDE OF THE FRONTS ACROSS THE CENTRAL ATLC. BEHIND THE
FRONTS...A QUASI-STATIONARY 1024 MB SURFACE HIGH IS CENTERED
NEAR 32N46W. SUBSIDENCE ASSOCIATED WITH THIS SURFACE HIGH IS
RESULTING IN GENERALLY FAIR WEATHER BEHIND THE FRONTAL BOUNDARY.
ACROSS THE E ATLC...A SURFACE RIDGE IS PRESENT WHERE MAINLY
ZONAL FLOW ALOFT IS OCCURRING AND FAIR WEATHER CONDITIONS
PERSIST. ACROSS THE TROPICAL ATLC...AN UPPER LEVEL RIDGE IS S OF
16N E OF 50W WITH AN UPPER LEVEL HIGH NEAR 5N32W. UPPER LEVEL
DIVERGENCE ASSOCIATED WITH THE UPPER LEVEL HIGH AND RIDGE IS
ENHANCING THE CONVECTION ASSOCIATED WITH THE ITCZ AND THE
TROPICAL WAVE ALONG 50W S OF 9N.

$$
HUFFMAN





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