[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 112352
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT SUN JUL 11 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
2315 UTC...


...TROPICAL WAVES...

TROPICAL WAVE HAS MOVED OFF W AFRICA ALONG 17W/18W S OF 17N
MOVING W 10-15 KT. BROAD MID LEVEL CYCLONIC ROTATION IS OBSERVED
ALONG THE WAVE AXIS NEAR 11N ON SATELLITE IMAGERY. WAVE IS
EMBEDDED WITHIN A MOISTURE MAXIMUM AS INDICATED ON THE TOTAL
PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE/STRONG CONVECTION
IS FROM 12N-15N E OF 19W TO INLAND OVER W AFRICA.

TROPICAL WAVE IS ALONG 38W/39W S OF 16N MOVING W NEAR 15 KT.
WAVE IS EMBEDDED WITHIN A LARGE AREA OF DRY SAHARAN AIR AND DUST
PARTIALLY MASKING THE SATELLITE SIGNATURE AND SUPPRESSING ANY
SHOWER ACTIVITY/CONVECTION.

TROPICAL WAVE IN THE CENTRAL CARIBBEAN IS ALONG 75W S OF 19N
MOVING W NEAR 20 KT. WAVE IS AT THE TRAILING EDGE A BROAD AREA
OF DEEP LAYER MOISTURE THAT COVERS THE CARIBBEAN W OF 76W AS
INDICATED ON THE TOTAL PRECIPITABLE WATER IMAGERY AND AT TOWARD
THE LEADING EDGE OF THE LARGE AREA OF DRY SAHARAN AIR AND DUST
THAT COVERS THE TROPICAL ATLC THUS LIMITING THE SHOWER ACTIVITY/
CONVECTION.

TROPICAL WAVE IS ALONG 84W S OF 19N MOVING W 15-20 KT. WAVE IS
EMBEDDED WITHIN A BROAD AREA OF DEEP LAYER MOISTURE THAT COVERS
MOST OF THE CARIBBEAN AS INDICATED ON THE TOTAL PRECIPITABLE
WATER IMAGERY. LARGE AREA OF SCATTERED SHOWERS/THUNDERSTORMS ARE
FROM 11N-18N W OF 82W TO INLAND OVER CENTRAL AMERICA AND THE
YUCATAN PENINSULA ENHANCED BY AN UPPER RIDGE OVER THE W
CARIBBEAN.

THE TROPICAL WAVE OVER THE S GULF OF MEXICO IS NOW ANALYZED AS
A SURFACE TROUGH. SEE GULF OF MEXICO BELOW.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 11N14W 6N27W 9N41W 8N47W 9N55W
8N63W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION
ARE WITHIN 75 NM OF LINE FROM 9N14W TO 5N28W. SMALL CLUSTERS OF
SCATTERED MODERATE CONVECTION ARE FROM 2N-8N BETWEEN 35W-46W.

...DISCUSSION...

GULF OF MEXICO...
THE TROPICAL WAVE THAT WAS IN THE S GULF IS NOW A SURFACE TROUGH
THAT EXTENDS FROM 20N96W SE ACROSS S MEXICO THROUGH THE ISTHMUS
OF TEHUANTEPEC. AN UPPER RIDGE IS ANCHORED OVER THE YUCATAN
PENINSULA NEAR 18N89W COVERING THE S GULF S OF 23N WITH A SECOND
UPPER RIDGE COVERING THE N GULF ANCHORED OVER CENTRAL TEXAS
EXTENDING AN AXIS ALONG THE N GULF COAST ACROSS CENTRAL FLORIDA
INTO THE FAR W ATLC OVER LAKE OKEECHOBEE. A SURFACE RIDGE
EXTENDS FROM THE W ATLC ACROSS S FLORIDA OVER MUCH OF THE GULF
WITH A 1019 MB HIGH NEAR 26N87W. A SURFACE TROUGH IS ACROSS NE
FLORIDA FROM JACKSONVILLE INTO THE NE GULF TO NEAR 29N86W
GENERATING SCATTERED SHOWERS/THUNDERSTORMS INLAND OVER FLORIDA N
OF LAKE OKEECHOBEE AND FROM THE FLORIDA PANHANDLE TO SE
LOUISIANA. THIS SCENARIO IS LEAVING THE GULF UNDER MOSTLY CLEAR
SKIES THIS EVENING.

CARIBBEAN SEA...
AN UPPER RIDGE IS ANCHORED OVER THE YUCATAN PENINSULA NEAR
18N89W COVERING THE W CARIBBEAN W OF 80W AND IS ENHANCING THE
ACTIVITY ASSOCIATED WITH THE TROPICAL WAVE ALONG 84W. AN UPPER
LOW IS OVER THE CENTRAL CARIBBEAN NEAR 17N75W. THE ITCZ EXTENDS
ACROSS PANAMA INTO THE E PACIFIC REGION AND COUPLED WITH THE
UPPER LOW OVER THE CENTRAL CARIBBEAN IS GENERATING SCATTERED
SHOWERS/ISOLATED THUNDERSTORMS S OF 13N FROM 72W-82W. AFTERNOON
HEATING IS DEVELOPING THUNDERSTORMS INLAND OVER HISPANIOLA...
CUBA...AND JAMAICA WHILE THE NORTHERLY FLOW ALOFT IS FORCING
SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS INTO THE
CARIBBEAN WATERS WITHIN 60 NM ALONG THE SOUTHERN COASTLINES.  A
SECOND UPPER RIDGE IS OVER THE FAR E CARIBBEAN S OF 17N E OF 67W
AND IS ENHANCING SCATTERED SHOWERS AND POSSIBLE ISOLATED
THUNDERSTORMS S OF 15N BETWEEN THE WINDWARD ISLANDS AND 66W
LEAVING THE REMAINDER OF THE CARIBBEAN UNDER MOSTLY CLEAR SKIES
THIS EVENING. VISIBLE SATELLITE IMAGERY INDICATED THAT A LARGE
AREA OF DRY SAHARAN AIR AND DUST COVERS THE CARIBBEAN E OF 76W.

ATLANTIC OCEAN...
AN UPPER RIDGE EXTENDS FROM THE N GULF OF MEXICO ACROSS CENTRAL
FLORIDA INTO THE FAR W ATLC TO NEAR 27N76W. THERE IS STATIONARY
FRONT N OF THE DISCUSSION AREA WITH A SURFACE TROUGH EXTENDING
FROM NE FLORIDA INTO THE GULF OF MEXICO WITH A SEABREEZE SURFACE
TROUGH EXTENDING FROM 29N79W TO INLAND OVER S FLORIDA NEAR WEST
PALM BEACH. SCATTERED SHOWERS/THUNDERSTORMS ARE N OF A LINE FROM
NEAR MELBOURNE FLORIDA TO BEYOND 32N75W. A WEAKER SURFACE TROUGH
IS JUST TO THE E EXTENDING FROM 31N74W ACROSS THE N BAHAMA
ISLANDS TO 24N79W. A BROAD UPPER TROUGH IS IN THE CENTRAL ATLC
EXTENDING THROUGH 32N57W TO 18N61W GENERATING ISOLATED SHOWERS/
THUNDERSTORMS FROM 21N-28N BETWEEN 66W-73W. A SURFACE RIDGE
DOMINATES DOMINATES THE REMAINDER OF THE ATLC E OF 70W ANCHORED
BY A 1030 MB HIGH OVER 900 NM ENE OF BERMUDA AND THEN NARROWS
OVER THE REMAINDER OF THE W ATLC INTO THE GULF OF MEXICO OVER S
FLORIDA. THE REMAINDER OF THE CENTRAL ATLC AND INTO THE E ATLC
IS UNDER STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT LEAVING THE
AREA UNDER FAIR WEATHER THIS EVENING. VISIBLE SATELLITE IMAGERY
INDICATED THAT A LARGE AREA OF DRY SAHARAN AIR AND DUST COVERS
MOST OF THE TROPICAL ATLC ACROSS THE LESSER ANTILLES INTO THE
CARIBBEAN.

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

$$
PAW





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