[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 011712
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT SAT AUG 01 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1630 UTC.

...TROPICAL WAVES...

A TROPICAL WAVE EXTENDS ALONG 23N34W 18N32W 13N29W 5N29W MOVING
W NEAR 20 KT. VISIBLE SATELLITE IMAGERY AND SATELLITE DERIVED
WINDS INDICATE LOW-LEVEL CYCLONIC FLOW IN THE VICINITY OF THIS
WAVE AXIS. THE N PORTION OF THIS WAVE COINCIDES WITH A RELATIVE
MOISTURE MAXIMUM OBSERVED IN TOTAL PRECIPITABLE WATER
IMAGERY...WHILE THE S PORTION OF THE WAVE LIES AHEAD OF A DEEP
LAYER MOISTURE MAXIMUM EMBEDDED WITHIN THE ITCZ. A DRY SAHARAN
AIR LAYER IS E OF THE WAVE AXIS INHIBITING ANY DEEP CONVECTION.
HOWEVER...SCATTERED SHOWERS ARE EMBEDDED WITHIN THE ITCZ S OF
14N BETWEEN 28W-32W.

A TROPICAL WAVE EXTENDS ALONG 25N51W 18N55W 6N55W MOVING W 20-25
KT. VISIBLE SATELLITE IMAGERY AND SATELLITE DERIVED WINDS
INDICATE LOW-LEVEL CYCLONIC FLOW IN THE VICINITY OF THE WAVE
AXIS. NO DEEP CONVECTION IS CURRENTLY ASSOCIATED WITH THIS WAVE.
HOWEVER...SCATTERED SHOWERS ARE FROM 8N-12N BETWEEN 53W-57W.

A TROPICAL WAVE EXTENDS ALONG 21N79W 13N83W EQ84W MOVING W NEAR
25 KT. THIS WAVE COINCIDES WITH A DEEP LAYER MOISTURE MAXIMUM
OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY. AN UPPER LEVEL LOW
IS NEAR THE N PORTION OF THIS WAVE NEAR 20N82W ENHANCING
SCATTERED MODERATE CONVECTION OVER ERN CUBA FROM 19N-21N BETWEEN
76W-78W...AND SCATTERED MODERATE/ISOLATED STRONG CONVECTION W OF
THE WAVE AXIS FROM 12N-18N BETWEEN 82W-90W.



...THE ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 12N14W 10N20W 10N40W 10N54W AND
INTO NRN VENEZUELA NEAR 9N63W. SCATTERED MODERATE CONVECTION IS
JUST OFF THE AFRICA COAST FROM 6N-12N BETWEEN 14W-20W. SIMILAR
CONVECTION IS FROM 9N-10N BETWEEN 59W-63W.

...DISCUSSION...

THE GULF OF MEXICO...
A BROAD SURFACE RIDGE COVERS THE MAJORITY OF THE GULF OF MEXICO
BRINGING GENERALLY FAIR WEATHER ACROSS THE AREA. A 1016 MB
SURFACE HIGH IS AT THE MEXICAN COAST NEAR 22N98W. DRY AIR AND
SUBSIDENCE ALOFT AROUND AN UPPER LEVEL HIGH CENTERED OVER NRN
MEXICO NEAR 28N104W SUPPORTS THE SURFACE RIDGE AND ASSOCIATED
FAIR WEATHER. A WEAK SURFACE TROUGH IS ANALYZED ACROSS THE SE
GULF EXTENDING ACROSS S FLORIDA FROM 27N80W TO WRN CUBA NEAR
22N84W. SURFACE CONVERGENCE NEAR THIS TROUGH ALONG WITH UPPER
LEVEL DIFFLUENCE BETWEEN THE UPPER LEVEL RIDGE COVERING THE GULF
AND AN UPPER LEVEL LOW S OF CUBA NEAR 20N82W ARE SUPPORTING
ISOLATED SHOWERS/POSSIBLE THUNDERSTORMS ACROSS THE ERN GULF E OF
89W. ANTICYCLONIC SURFACE FLOW IS PRESENT AROUND THE SURFACE
RIDGE WITH WINDS REACHING 15 KT ACROSS THE WRN GULF. EXPECT THE
N PORTION OF A TROPICAL WAVE TO MOVE ACROSS THE SRN GULF LATER
TONIGHT AND SUN.

THE CARIBBEAN SEA...
A TROPICAL WAVE EXTENDING FROM 21N79W TO 10N83W AND INTO THE E
PACIFIC IS SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS ACROSS THE
NW CARIBBEAN FROM 12N-18N BETWEEN 82W-90W INCLUDING PORTIONS OF
NICARAGUA AND HONDURAS. SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO
ACROSS PORTIONS OF CUBA N OF 20N BETWEEN 75W-84W. BOTH AREAS OF
ACTIVITY ARE ENHANCED BY UPPER LEVEL DIFFLUENCE ASSOCIATED WITH
AN UPPER LEVEL LOW S OF CUBA NEAR 20N82W. ISOLATED SHOWERS ARE
IN THE SW CARIBBEAN S OF 11N BETWEEN 76W-79W DUE TO SURFACE
CONVERGENCE NEAR A 1009 MB SURFACE LOW OVER COLUMBIA NEAR 8N76W.
THE REMAINDER OF THE CARIBBEAN IS EXPERIENCING GENERALLY FAIR
WEATHER INFLUENCED BY SUBSIDENCE ALOFT AND A DRY SAHARAN AIR
LAYER E OF 76W. FRESH TO STRONG TRADE WINDS ARE PRESENT ACROSS
MUCH OF THE CARIBBEAN. EXPECT A SECOND TROPICAL WAVE TO REACH
THE E CARIBBEAN LATER TONIGHT.

THE ATLANTIC OCEAN...
SCATTERED SHOWERS/THUNDERSTORMS ARE ACROSS THE FAR NW ATLC N OF
29N W OF 77W DUE TO UPPER LEVEL DIFFLUENCE BETWEEN AN UPPER
LEVEL RIDGE ACROSS THE GULF OF MEXICO AND AN UPPER LEVEL TROUGH
OVER THE ERN CONUS N OF 33N. FARTHER E...ISOLATED SHOWERS ARE N
OF 28N BETWEEN 56W-65W ASSOCIATED WITH AN UPPER LEVEL LOW NEAR
32N61W. ELSEWHERE ACROSS THE ATLC...A BROAD SURFACE RIDGE
DOMINATES ANCHORED BY A 1031 MB SURFACE HIGH NEAR 35N54W...AND A
1029 MB SURFACE HIGH NEAR 35N43W. ACROSS THE TROPICAL ATLC...A
BROAD UPPER LEVEL RIDGE COVERS THE AREA S OF 25N CENTERED NEAR
18N40W.

$$
WALTON





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