000
AXNT20 KNHC 220515
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT SUN JUN 22 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
0445 UTC.

...TROPICAL WAVES...
TROPICAL WAVE IS ALONG 37W/38W S OF 16N MOVING W NEAR 20 KT. 
BROAD MID LEVEL CYCLONIC TURNING IS EVIDENT ON SATELLITE IMAGERY 
NEAR 9N. SCATTERED MODERATE/STRONG CONVECTION IS FROM 8N-12N 
BETWEEN 36W-41W.

TROPICAL WAVE IS IN THE CENTRAL CARIBBEAN ALONG 76W/77W S OF 21N 
MOVING W NEAR 20 KT. SATELLITE IMAGERY SHOWS LOW LEVEL 
INVERTED-V CURVATURE. ISOLATED SHOWERS ARE FROM JAMAICA TO CUBA 
BETWEEN 76W-80W. 

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 11N15W 9N22W 7N31W 8N48W 6N55W. 
CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE 
FROM THE EQUATOR TO 8N BETWEEN 24W-36W AND FROM THE EQUATOR TO 
9N BETWEEN 39W-48W. SMALL CLUSTERS OF SIMILAR CONVECTION ARE 
WITHIN 120 NM OF LINE FROM 10N15W TO 6N24W. 

...DISCUSSION...

GULF OF MEXICO...
AN UPPER-LEVEL RIDGE OVER MEXICO EXTENDS INTO THE FAR W GULF 
WITH A SECOND UPPER RIDGE EXTENDING FROM OVER THE YUCATAN 
PENINSULA AND THE SE GULF INCLUDING FLORIDA STRAITS. BETWEEN IS 
A SHORTWAVE UPPER TROUGH EXTENDING FROM LOUISIANA TO THE BAY OF 
CAMPECHE. UPPER DIVERGENCE BETWEEN THIS TROUGH AND THE RIDGES IS 
KEEPING MOST OF THE GULF UNDER CLOUD COVER TONIGHT WITH CLUSTERS 
OF SCATTERED SHOWERS/THUNDERSTORMS N OF 27N W OF 86W TO INLAND 
OVER LOUISIANA AND TEXAS WITH SCATTERED SHOWERS/ISOLATED 
THUNDERSTORMS WITHIN 120 NM OF LINE FROM 27N85W INTO THE BAY OF 
CAMPECHE AND S MEXICO NEAR 18N94W. THE W GULF FROM 21N-27N W OF 
94W IS THE ONLY CLEAR REGION TONIGHT. A WEAK SURFACE RIDGE 
EXTENDS ACROSS THE GULF FROM THE W ATLC CREATING A WEAK PRESSURE 
PATTERN AND IS PROVIDING LIGHT AND VARIABLE WINDS ACROSS THE 
REGION.

CARIBBEAN...
AN UPPER RIDGE ANCHORED OVER CENTRAL AMERICA THAT EXTENDS INTO 
THE E GULF OF MEXICO COVERS THE W CARIBBEAN W OF 80W WHILE A 
SECOND UPPER RIDGE ANCHORED IN THE TROPICAL ATLC COVERS THE SE 
CARIBBEAN. AN UPPER TROUGH IS BETWEEN THESE UPPER RIDGES 
EXTENDING FROM THE CENTRAL ATLC ACROSS THE LEEWARD ISLANDS S OF 
HISPANIOLA TO PANAMA. UPPER LEVEL DIFFLUENCE IS GENERATING 
SCATTERED SHOWERS/THUNDERSTORMS ALONG THE COAST OF CENTRAL 
AMERICA FROM 10N-16N BETWEEN 82W-84W AS WELL AS N OF 21N TO 
INLAND OVER W CUBA FROM 80W-83W. MODERATE/STRONG EASTERLY TRADE 
WINDS DOMINATE MOST OF THE CARIBBEAN DUE TO THE TIGHT PRESSURE 
GRADIENT BETWEEN THE SURFACE RIDGE OVER THE ATLC AND THE LOWER 
PRESSURE OVER SOUTH AMERICA. 

ATLANTIC...
NARROW SURFACE RIDGE AXIS EXTENDS FROM THE CARIBBEAN/GULF OF 
MEXICO OVER THE W ATLC ACROSS S FLORIDA TO NEAR 31N72W AND 
PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS/ 
THUNDERSTORMS OVER THE N BAHAMA ISLANDS FROM CUBA TO 28N FROM 
76W-80W. THE UPPER LEVELS ARE DOMINATED BY AN UPPER TROUGH THAT 
EXTENDS FROM THE NE ATLC ACROSS THE BASIN ALONG 32N22W ALONG 
26N42W 23N60W CROSSING THE LEEWARD ISLANDS INTO THE CARIBBEAN.  
A LARGE SURFACE RIDGE COVERS THE ENTIRE ATLC BASIN FROM AFRICA 
INTO THE GULF OF MEXICO ANCHORED BY A 1029 MB HIGH CENTERED JUST 
N OF THE REGION NEAR 33N42W. MODERATE SUBSIDENCE AND SOMEWHAT 
DRY STABLE AIR ALSO DOMINATES THE ATLC E OF 75W GIVING THE AREA 
FAIR WEATHER TONIGHT. BROAD E/W UPPER RIDGE DOMINATES THE 
TROPICAL ATLC FROM THE CAPE VERDE ISLANDS TO OVER THE E 
CARIBBEAN ENHANCING THE CONVECTION ASSOCIATED WITH THE ITCZ. 

$$
WALLACE