[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 122352
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT THU AUG 12 2010

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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2345 UTC.

...TROPICAL WAVES...

TROPICAL WAVE EXTENDS FROM 18N32W TO 6N29W MOVING W 10-15 KT.
THE WAVE LOCATION IS BETTER APPARENT IN THE MID LEVELS OF THE
ATMOSPHERE...SUCH AS THE 700 MB STREAMLINE ANALYSIS. SATELLITE
IMAGERY INDICATES WEAK LOW-LEVEL CYCLONIC FLOW IN THE VICINITY
OF THE WAVE AXIS CONFIRMED BY SATELLITE DERIVED WINDS. DUE TO A
LARGE AREA OF DRY SAHARAN AIR AND DUST EAST OF THE WAVE
AXIS...CONVECTION IS CONSTRAINED TO THE ITCZ.

TROPICAL WAVE IS NORTHEAST OF THE LEEWARD ISLANDS FROM 22N58W TO
16N60W MOVING NW 10-15 KT. SATELLITE IMAGERY INDICATES
LOW/MID-LEVEL CYCLONIC TURNING AROUND THE WAVE AXIS. THE WAVE
ALSO LIES EMBEDDED IN A DEEP LAYER MOISTURE MAXIMUM EVIDENT IN
TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE/ISOLATED
STRONG CONVECTION IS FROM 16N TO 20N BETWEEN 57W AND 61W...AND
FROM 20N TO 23N BETWEEN 54W AND 57W.

TROPICAL WAVE EXTENDS ACROSS HISPANIOLA FROM 23N70W TO 17N73W
MOVING WNW NEAR 10 KT. TOTAL PRECIPITABLE WATER IMAGERY
INDICATES AN AREA OF ENHANCED MOISTURE ACROSS THE N CENTRAL
CARIBBEAN IN WHICH THE WAVE IS EMBEDDED. WEAK TURNING IS
OBSERVED IN THE VICINITY OF THE WAVE. MOST OF THE SHOWER
ACTIVITY ASSOCIATED WITH THE WAVE IS OVER HISPANIOLA AND WITHIN
90 NM OFF THE SOUTHERN COAST OF THE ISLAND. DOPPLER RADAR
IMAGERY FROM PUERTO RICO ALSO INDICATES SCATTERED SHOWERS ACROSS
THE ISLAND WITH ISOLATED SHOWERS SURROUNDING THE ISLAND FROM 15N
TO 20N WEST OF 63W.

...ITCZ...

THE ITCZ AXIS IS ANALYZED FROM WEST AFRICA OVER SIERRA LEONE
NEAR 8N12W...CONTINUING WESTWARD ALONG 6N25W 4N35W 5N45W TO THE
COAST OF GUYANA NEAR 7N58W CONTINUING WESTWARD ACROSS NORTHERN
SOUTH AMERICA. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION
IS WITHIN 130 NM ON EITHER SIDE OF THE AXIS EAST OF 36W.

...DISCUSSION...

GULF OF MEXICO...
DOPPLER RADAR IMAGERY INDICATES THAT THE REMNANT CIRCULATION OF
TROPICAL DEPRESSION FIVE IS LOCATED OVER CAT ISLAND...OFF THE
COAST OF MISSISSIPPI...NEAR 30N89W...ANALYZED AS A 1008 MB LOW
CENTER AT 2200 UTC. AT THIS POINT...MOST OF THE CONVECTION
PRODUCED BY THIS SYSTEM HAS MOVED INLAND. YET...SCATTERED
MODERATE TO ISOLATED STRONG CONVECTION REMAINS OVER THE NORTHERN
GULF COAST NORTH OF 27N BETWEEN 82W AND 90W. TOTAL PRECIPITABLE
WATER IMAGERY SHOWS THE CONVECTION IS FUELED BY PLENTY OF
LOW-MID LEVEL MOISTURE EMBEDDED IN THE SYSTEM ADVECTING ACROSS
THE SOUTHERN STATES WEST OF 94W. WATER VAPOR IMAGERY INDICATES
MODERATELY DRY AIR ACROSS THE SE GULF KEEPING WEATHER CONDITIONS
FAIR WITH CLEAR SKIES. CYCLONIC FLOW ALOFT IS NOTED OVER THE
WESTERN GULF...AROUND AN UPPER LEVEL LOW/TROUGH OVER NORTHEAST
MEXICO. THIS UPPER LEVEL FEATURE IS DRAWING MID-UPPER LEVEL
MOISTURE FROM THE EASTERN PACIFIC SUPPORTING A FEW ISOLATED
SHOWERS WITHIN 100 NM OFF THE COASTAL WATERS OF MEXICO FROM 19N
TO 24N. SHORT RANGE COMPUTER MODELS KEEP SCATTER CONVECTION
ACROSS THE NORTHERN GULF AS THE REMNANTS OF T.D. FIVE DRIFT
FARTHER INLAND...WHILE SURFACE RIDGING BUILDS ACROSS THE GULF
FROM THE WEST ATLC.

CARIBBEAN SEA...
A MID-UPPER LEVEL TROUGHINESS COVERS THE NORTH CENTRAL CARIBBEAN
SUPPORTING A WEAK SURFACE TROUGH EXTENDING FROM THE NW BAHAMAS
NEAR 25N77W ACROSS CENTRAL CUBA TO NEAR 19N78W. SURFACE
CONVERGENCE NEAR THE TROUGH IS SUPPORTING SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS NORTH OF 16N BETWEEN 75W AND 80W. FARTHER
EAST...A TROPICAL WAVE ACROSS CENTRAL HISPANIOLA IS SUPPORTING
SCATTERED SHOWERS AND THUNDERSTORMS SOUTH OF THE ISLAND NORTH OF
16N EAST OF 72W...INCLUDING PUERTO RICO AND SURROUNDING WATERS.
A BROAD AREA OF CYCLONIC TURNING SUPPORTING SCATTERED SHOWERS
AND THUNDERSTORMS IS OVER THE SOUTHWEST CARIBBEAN SOUTH OF 14N
WEST OF 73W ENHANCED BY SURFACE CONVERGENCE NEAR AN EXTENSION OF
THE ITCZ ACROSS COSTA RICA...PANAMA...AND NORTHERN COLOMBIA.
WATER VAPOR IMAGERY INDICATES VERY DRY AIR ALOFT ACROSS THE
SOUTHEAST  CARIBBEAN AND OVERALL DRY AND STABLE ATMOSPHERE ALOFT
ELSEWHERE ACROSS THE CARIBBEAN MAINTAINING FAIR WEATHER
CONDITIONS. EXPECT SHOWER/THUNDERSTORM ACTIVITY TO REMAIN ACROSS
THE SOUTHWEST AND CENTRAL CARIBBEAN OVER THE NEXT 24 HOURS.
SHOWER ACTIVITY MAY BEGIN TO IMPACT THE NORTHERN LEEWARD ISLANDS
AS A TROPICAL WAVE TO EAST OF THE ISLANDS MOVES NORTHWEST.

ATLANTIC OCEAN...
A WEAK SURFACE TROUGH EXTENDS FROM THE NORTHWEST BAHAMAS ACROSS
EASTERN CUBA ALONG 25N77W TO 19N78W SUPPORTING SCATTERED
SHOWERS WITHIN 40 NM ON EITHER SIDE OF THE TROUGH. DRY/STABLE
AIR ALOFT IS ELSEWHERE ACROSS THE WESTERN ATLC WEST OF 70W
PROVIDING FAIR WEATHER CONDITIONS WITH A FEW HIGH CLOUDS.
FARTHER EAST...AN UPPER LEVEL TROUGH/LOW NEAR 30N57W SUPPORTS A
WEAK SURFACE TROUGH IN THE CENTRAL ATLC FROM 26N55W TO
25N58W...ENHANCING SCATTERED SHOWERS WITHIN 60 NM EITHER SIDE OF
THE AXIS. FARTHER EAST...BROAD SURFACE RIDGING DOMINATES THE
EASTERN ATLC ANCHORED BY AN ELONGATED HIGH PRESSURE CENTER WELL
NORTH OF THE DISCUSSION AREA. LAST VISIBLE SATELLITE IMAGES
OF THE DAY INDICATED A BROAD AREA OF SAHARAN DUST COVERING MOST
OF THE EASTERN ATLANTIC EAST OF 35W SUPPORTING STABLE CONDITIONS.

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$

GARCIA




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