[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 120508
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT SAT AUG 12 2006

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN
SECTIONS OF SOUTH AMERICA...AND THE ATLANTIC OCEAN TO THE
AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION
IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...
AND METEOROLOGICAL ANALYSIS.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0445 UTC.

...TROPICAL WAVES...
TROPICAL WAVE IS JUST INLAND ALONG THE W COAST OF AFRICA ALONG
16W/17W S OF 21N MOVING W 10-15 KT. WAVE HAS A WELL DEFINED MID
LEVEL ROTATION NEAR 16N ALTHOUGH CONVECTION HAS DIMINISHED OVER
THE PAST FEW HOURS. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE
INLAND AND WITHIN 120 NM ALONG THE COAST OF AFRICA FROM 12N-17N.

TROPICAL WAVE IS ALONG 49W/50W S OF 20N MOVING W 15 KT. WAVE
CONTINUES TO HAVE A WELL DEFINED LOW LEVEL INVERTED V-SHAPE
CURVATURE HOWEVER LACKS DEEP CONVECTION DUE A VERY DRY
ENVIRONMENT. ISOLATED THUNDERSTORMS ARE FROM 14N-18N BETWEEN
47W-51W.

TROPICAL WAVE IN THE CARIBBEAN IS ALONG 73W S OF 21N MOVING W 15
KT. WAVE IS MOVING BENEATH AN UPPER LOW WHICH IS PARTIALLY
MASKING THE SIGNATURE CURVATURE AND DIMINISHING AND ASSOCIATED
CONVECTION.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 12N18W 9N30W 13N49W 10N62W.
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM N
OF THE AXIS FROM 38W-41W AND FROM 52W-55W. CLUSTERS OF SCATTERED
MODERATE CONVECTION ARE WITHIN 180 NM S OF THE AXIS FROM
25W-37W.

...DISCUSSION...
GULF OF MEXICO...
THE UPPER LEVEL LOW REMAINS OVER THE W GULF CENTERED ALONG THE
TEXAS/MEXICO BORDER NEAR 26N97W COVERING THE AREA W OF 90W. THE
UPPER HIGH OFF THE COAST OF NE FLORIDA AND THE UPPER RIDGE
EXTENDING ACROSS THE W ATLC ARE GIVING THE REMAINDER OF THE GULF
S TO SE UPPER FLOW WITH DRY UPPER AIR. AT THE SURFACE...A RIDGE
EXTENDS FROM THE W ATLC ACROSS FLORIDA WITH A 1014 MB HIGH IN
THE CENTRAL GULF NEAR 26N90W. SOME UPPER MOISTURE BEING ADVECTED
ACROSS S MEXICO INTO THE SW GULF BUT IS NOT ENOUGH TO SUPPORT
ANY SIGNIFICANT SHOWER ACTIVITY. THUS...THE GULF IS RELATIVE
QUIET AGAIN TONIGHT.

CARIBBEAN SEA...
THE UPPER RIDGE OVER THE W ATLC EXTENDS S OVER CUBA AND THE
YUCATAN CHANNEL GIVING ENOUGH DIFFLUENCE TO DEVELOP ISOLATED
SHOWERS/THUNDERSTORMS N OF 17N W OF 74W. AN UPPER LOW IS IN THE
CENTRAL CARIBBEAN NEAR 16N74W WHICH IS AN EXTENSION FROM AN
UPPER TROUGH IN THE W ATLC. THE TROPICAL WAVE IS MOVING BENEATH
THIS UPPER LOW. THE E CARIBBEAN REMAINS UNDER THE INFLUENCE OF
AN UPPER RIDGE THAT COVERS THE TROPICAL ATLC AND IS ADVECTING IN
MORE DRY AIR OVER THE LESSER ANTILLES. MODERATE/STRONG
TRADEWINDS ARE ACROSS THE CARIBBEAN S OF 17N.

ATLANTIC OCEAN...
AND UPPER HIGH IS OFF THE NE COAST OF FLORIDA NEAR 29N80W
EXTENDING AN UPPER RIDGE ACROSS THE W ATLC TO THE CENTRAL ATLC
NEAR 30N56W BRINGING WITH IT SCATTERED MODERATE/ISOLATED STRONG
CONVECTION N OF 30N FROM 71W-79W AND SCATTERED SHOWERS/ISOLATED
THUNDERSTORMS N OF 30N FROM 58W-71W. AN UPPER TROUGH EXTENDS
FROM N OF THE REGION INTO THE W/CENTRAL ATLC NEAR 32N52W SW
ALONG 26N58W TO AN UPPER LOW NEAR N OF THE MONA PASSAGE NEAR
21N68W CONTINUING ACROSS HISPANIOLA INTO THE CENTRAL CARIBBEAN
AND YET ANOTHER UPPER LOW. A NARROWING DEEP LAYERED TROUGH IS N
OF THE E/CENTRAL ATLC N OF 26N FROM 35W-45W WITH A 1015 MB
SURFACE LOW N OF THE REGION AND A WEAK SURFACE TROUGH EXTENDING
THROUGH 32N34W SW TO 27N40W. AN UPPER RIDGE EXTENDS ACROSS THE
TROPICAL ATLC FROM AFRICA INTO THE E CARIBBEAN AND COVERS THE E
ATLC E OF 35W. HOWEVER...DUE TO THE ABUNDANCE OF DRY AIR...ANY
SHOWER ACTIVITY IS SEVERELY LIMITED. THE REMAINDER OF THE
SURFACE ATLC IS DOMINATED BY A SURFACE RIDGE WITH A SERIES OF
HIGHS EXTENDING ACROSS THE ATLC INTO THE GULF OF MEXICO THROUGH
A 1020 MB HIGH IN THE E ATLC NEAR 29N29W AND A 1018 MB HIGH IN
THE CENTRAL ATLC NEAR 24N55W. THIS IS GIVING THE ENTIRE AREA
LITTLE IN THE WAY OF CLOUDS MUCH LESS SHOWER ACTIVITY.

$$
WALLACE


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