[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 310611
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT SUN AUG 31 2008

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0515 UTC.

...SPECIAL FEATURES...
HURRICANE GUSTAV IS CENTERED NEAR 23.1N 83.8W AT 31/0300 UTC OR
OVER THE SOUTHEASTERN GULF OF MEXICO ABOUT 90 MILES...145
KM...WEST OF HAVANA CUBA AND ABOUT 530 MILES...850
KM...SOUTHEAST OF THE MOUTH OF THE MISSISSIPPI RIVER.
MOVING NW AT 13 KT. THE MINIMUM CENTRAL IS 948 MB. MAXIMUM
SUSTAINED WIND SPEED IS 120 KT WITH GUSTS TO 150 KT. PLEASE SEE
THE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS
MIATCMAT2/ WTNT22 KNHC AND/OR THE PUBLIC ADVISORY MIATCPAT2/
WTNT32 KNHC FOR MORE DETAILS. GUSTAV IS AN EXTREMELY DANGEROUS
CATEGORY FOUR HURRICANE ON THE SAFFIR-SIMPSON HURRICANE SCALE.
GUSTAV'S CENTER HAS TRAVERSED CUBA AND IS NOW IN THE GULF OF
MEXICO. IT IS PRESENTLY STRENGTHENING AGAIN AFTER WEAKENING A
BIT OVER W CUBA. OUTFLOW IS BEST N OF THE CENTER. UPPER LEVEL
OUTFLOW WILL AGAIN BECOME MORE SYMMETRICAL AS GUSTAV MOVES AWAY
FROM CUBA. NUMEROUS STRONG CONVECTION IS WITHIN 90 NM OF THE
CENTER. SCATTERED MODERATE CONVECTION COVERS THE REMAINDER OF
THE AREA FROM 22N-26N BETWEEN 79W-86W...TO INCLUDE OUTER
RAINBANDS ACROSS THE FLORIDA PENINSULA AND ERN GULF OF MEXICO.

TROPICAL STORM HANNA IS CENTERED NEAR 22.9N 67.8W AT 31/0300 UTC
OR ABOUT 230 MILES...375 KM...EAST-NORTHEAST OF GRAND TURK
ISLAND. MOVING WNW AT 7 KT. ESTIMATED MINIMUM CENTRAL PRESSURE
IS 1000 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO
55 KT. PLEASE SEE THE LATEST NHC FORECAST/ADVISORY UNDER
AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC AND/OR THE PUBLIC
ADVISORY MIATCPAT3/ WTNT33 KNHC FOR MORE DETAILS. HANNA
CONTINUES TO EXPERIENCE WLY SHEAR. MUCH OF THE CONVECTION IS
LOCATED E OF THE CENTER. SCATTERED MODERATE TO ISOLATED STRONG
CONVECTION IS FROM 20N-26N BETWEEN 64W-67W. SCATTERED MODERATE
CONVECTION IS ALSO FROM 24N-26N BETWEEN 67W-69W.

TROPICAL WAVE IS ALONG 28W S OF 20N WITH A 1009 MB SURFACE LOW
ALONG THE WAVE NEAR 15N. THE SYSTEM IS MOVING W 10-15 KT. A
BROAD MID LEVEL CYCLONIC ROTATION IS OBSERVED ON SATELLITE
IMAGERY WITH ASSOCIATED CONVECTION MOSTLY LOCATED NORTH OF THE
LOW. SCATTERED MODERATE CONVECTION IS FROM 16N-18N BETWEEN
26W-29W. SCATTERED SHOWERS COVER THE REMAINDER OF THE AREA FROM
14N-22N BETWEEN 23W-32W. CONDITIONS APPEAR CONDUCIVE FOR
DEVELOPMENT AND THIS SYSTEM COULD BECOME A TROPICAL DEPRESSION
DURING THE NEXT COUPLE OF DAYS.

...TROPICAL WAVES...
TROPICAL WAVE IS ALONG 48W S OF 25N MOVING WNW NEAR 10 KT. A
1009 MB LOW IS EMBEDDED ON THE WAVE AXIS NEAR 21N48W. AN
INVERTED-V SATELLITE SIGNATURE IS OBSERVED WITH THIS SYSTEM WELL
N OF THE ITCZ. SCATTERED MODERATE TO STRONG CONVECTION IS E OF
THE WAVE AXIS FROM 19N-24N BETWEEN 43W-48W.

...THE ITCZ...
THE ITCZ AXIS IS ANALYZED ALONG 17N16W 15N27W 9N32W 11N50W
10N61W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS ALONG
THE W AFRICAN COAST FROM 7N-11N BETWEEN 13W-17W. SCATTERED
MODERATE CONVECTION IS FURTHER N FROM 14N-17N BETWEEN 15W-19W.
ISOLATED MODERATE CONVECTION IS FROM 6N-10N BETWEEN 28W-40W.

...DISCUSSION...

GULF OF MEXICO...
HURRICANE GUSTAV IS THE MAIN TOPIC FOR THE SE GULF OF MEXICO...
STRAITS OF FLORIDA...AND FLORIDA PENINSULA...AS IT CONTINUES
TRACKING NW TOWARDS THE NORTH CENTRAL GULF. SEE SPECIAL FEATURES
ABOVE. OVERCAST SKIES ARE OVER THE E GULF E OF 90W. MOSTLY FAIR
WEATHER IS OVER THE W GULF BETWEEN 90W-96W. IN THE UPPER LEVELS
...AN UPPER TROUGH IS OVER THE NW GULF OF MEXICO. UPPER LEVEL
DIFFLUENCE FROM THIS TROUGH IS GENERATING CLUSTERS OF SCATTERED
SHOWERS AND ISOLATED TSTMS OVER THE FAR WRN GULF AND MEXICO W OF
96W. EXPECT GUSTAV TO MAKE LANDFALL AS A MAJOR HURRICANE OVER
THE NORTH CENTRAL GULF AROUND MONDAY AFTERNOON.

CARIBBEAN SEA...
HURRICANE GUSTAV IS MOVING AWAY FROM CUBA BUT CONVECTION REMAINS
OVER CUBA W OF 78W. SEE SPECIAL FEATURES ABOVE. SCATTERED
SHOWERS REMAIN OVER THE NRN LEEWARD ISLANDS AND THE VIRGIN
ISLANDS ASSOCIATED WITH OUTER RAINBANDS OF T.S. HANNA. SCATTERED
MODERATE TO ISOLATED STRONG CONVECTION IS INLAND OVER HONDURAS
AND NICARAGUA FROM 11N-16N BETWEEN 85W-90W. IN THE UPPER
LEVELS...MOSTLY EASTERLY FLOW IS NOTED OVER THE CARIBBEAN MOSTLY
DUE TO OUTFLOW FROM GUSTAV AND HANNA. SUBSIDENCE AND DRY AIR IS
OVER THE WINDWARD ISLANDS. CONSIDERABLE UPPER LEVEL MOISTURE IS
OVER THE REMAINDER OF THE CARIBBEAN AND CENTRAL AMERICA.

ATLANTIC OCEAN...
A 1025 MB HIGH IS OVER THE CENTRAL ATLANTIC NEAR 34N44W. T.S.
HANNA AND THE TROPICAL WAVES ARE THE MAIN FEATURES IN THE
TROPICAL ATLANTIC. SEE ABOVE. IN THE UPPER LEVELS...AN UPPER
LEVEL LOW IS IN THE VICINITY OF HANNA NEAR 23N68W INFLUENCING
THE STORM. ANOTHER UPPER LEVEL LOW IS OVER THE CENTRAL ATLANTIC
NEAR 26N48W. AN UPPER LEVEL HIGH IS OVER THE E ATLANTIC NEAR
23N34W.

$$
FORMOSA





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