000
AXNT20 KNHC 220514
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT MON OCT 22 2007

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 
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...METEOROLOGICAL ANALYSIS... 
WEATHER OBSERVATIONS...AND RADAR.

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

...TROPICAL WAVES...
TROPICAL WAVE IS ALONG 55W S OF 20N MOVING W NEAR 10 KT. WAVE IS 
BENEATH A BROAD UPPER HIGH MASKING THE SATELLITE SIGNATURE WITH 
CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITHIN 
120 NM OF THE WAVE FROM 9N-15N. 

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 9N12W 6N22W 8N41W 12N53W 9N63W. 
SCATTERED MODERATE/STRONG CONVECTION IS FROM 9N-14N BETWEEN 
45W-50W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE 
FROM 5N-9N BETWEEN 18W-38W AND WITHIN 200 NM ALONG THE COAST OF 
AFRICA S OF 12N W OF 7W. 

DISCUSSION...

GULF OF MEXICO...
A WARM FRONT IS PUSHING N ACROSS THE N GULF EXTENDING FROM A 
FRONT IN THE W ATLC ACROSS THE FLORIDA PENINSULA NEAR TAMPA 
ALONG 29N88W TO 27N93W. HEAVY SHOWERS WITH EMBEDDED 
THUNDERSTORMS ARE MOVING N FROM 26N TO INLAND OVER THE N GULF 
COAST BETWEEN PENSACOLA FLORIDA AND THE MISSISSIPPI/LOUISIANA 
BORDER WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 27N 
BETWEEN APALACHICOLA BAY FLORIDA AND THE LOUISIANA/TEXAS BORDER. 
BROAD UPPER HIGH DOMINATES THE GULF CENTERED NEAR 24N91W. UPPER 
DIFFLUENCE TO THE E OF THE UPPER HIGH IS ENHANCING THE ACTIVITY 
ASSOCIATED WITH THE FRONTAL BOUNDARY AND SCATTERED SHOWERS/ 
ISOLATED THUNDERSTORMS DOTTING THE S GULF S OF 25N BETWEEN 
82W-93W. A MID LEVEL SHORTWAVE TROUGH IS ALONG THE W COAST OF 
THE FLORIDA PENINSULA ENHANCING SCATTERED SHOWERS E OF 82W 
ACROSS FLORIDA. 

CARIBBEAN SEA...
THE UPPER HIGH IN THE GULF OF MEXICO COVERS THE NW CARIBBEAN W 
OF 84W WITH AN UPPER LEVEL SHEAR AXIS BISECTING THE CENTRAL 
CARIBBEAN EXTENDING ACROSS E HISPANIOLA TO THE BORDER OF 
NICARAGUA/COSTA RICA. DRY STABLE AIR FROM THE W ATLC IS DRAWN SW 
INTO THE CARIBBEAN W OF THIS AXIS WHILE MOIST TROPICAL AIR IS TO 
THE E ACCOMPANIED BY CLUSTERS OF SCATTERED SHOWERS/ISOLATED 
THUNDERSTORMS MAINLY S OF 14N FROM THE ABC ISLANDS TO 76W AND 
FROM 10N-12N BETWEEN 81W-83W OFF THE CENTRAL AMERICA COAST. 
MODERATE/STRONG EASTERLY TRADE WINDS ACROSS THE N PORTION OF THE 
CARIBBEAN IS USHERING IN LOW LEVEL POPCORN TYPE SHOWERS 
ESPECIALLY N OF 16N E OF 83W. 

ATLANTIC OCEAN...
A DEEP LAYERED TROUGH N OF THE REGION IS DRAPING A COLD FRONT 
INTO THE W/CENTRAL ATLC JUST E OF BERMUDA NEAR 32N63W SW TO 
28N73W BECOMING NEAR STATIONARY TO OVER FLORIDA JUST N OF LAKE 
OKEECHOBEE CONTINUING INTO THE GULF OF MEXICO AS A WARM FRONT. 
UPPER RIDGE AXIS EXTENDS ACROSS THE FLORIDA PENINSULA JUST S OF 
LAKE OKEECHOBEE AND THE W ATLC ALONG 29N71W TO NEAR 29N65W 
ENHANCING SCATTERED SHOWERS N OF 28N W OF 78W TO OVER THE SE US. 
A SURFACE RIDGE IS BUILDING BEHIND THE FRONTAL BOUNDARY ANCHORED 
BY A PAIR OF 1027 MB HIGH OFF THE VIRGINIA COAST WELL N OF THE 
REGION. AN UPPER SHEAR AXIS EXTENDS FROM AN UPPER LOW IN THE 
E/CENTRAL ATLC NEAR 27N41W ALONG 23N53W INTO THE CARIBBEAN OVER 
E HISPANIOLA WITH A SWATH OF DRY STABLE AIR OVER THE REMAINDER 
OF THE W ATLC WITHIN 400 NM NW OF THE SHEAR AXIS W OF 55W INTO 
THE CARIBBEAN. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE 
ASSOCIATED WITH THE UPPER LOW COVERING THE AREA FROM 26N-30N 
BETWEEN 39W-43W. WEAK SURFACE RIDGE COVERS THE CENTRAL ATLC 
ANCHORED BY A 1025 MB HIGH WELL N OF THE REGION COVERING THE 
AREA FROM BETWEEN 40W AND THE FRONTAL BOUNDARY IN THE W ATLC. A 
LINGERING SURFACE TROUGH EXTENDS THROUGH 32N30W ALONG 25N39W TO 
23N48W WITH SCATTERED SHOWERS AND WIDELY ISOLATED THUNDERSTORMS 
WITHIN 150/180 NM OF THE SURFACE TROUGH E OF 41W. UPPER RIDGE 
COVERS THE REMAINDER OF THE E ATLC WITH THE AXIS ALONG 25W. DRY 
STABLE AIR COVERS THE FAR E ATLC WITH A SURFACE RIDGE EXTENDING 
E OF THE ABOVE SURFACE TROUGH. BROAD UPPER RIDGE COVERS MUCH OF 
THE TROPICAL ATLC S OF 22N FROM THE E CARIBBEAN TO JUST W OF THE 
CAPE VERDE ISLANDS. 

$$
WALLACE