000 AXNT20 KNHC 221108 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 56W S OF 21N MOVING W NEAR 10 KT. WAVE REMAINS BENEATH A BROAD UPPER HIGH PARTIALLY MASKING THE SATELLITE SIGNATURE. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 9N-16N BETWEEN 52W-57W. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 10N12W 8N20W 8N27W 6N41W 11N57W 10N63W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 10N-12N E OF 17W TO INLAND OVER GUINEA BISSAU. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 120 NM OF THE AXIS FROM 21W-33W AND ALONG THE COAST OF AFRICA FROM 3N-8N BETWEEN 9W-14W. DISCUSSION... GULF OF MEXICO... A WARM FRONT CONTINUES TO PUSH N OVER THE N GULF EXTENDING FROM A STATIONARY FRONT IN THE W ATLC ACROSS THE FLORIDA PENINSULA NEAR TAMPA ALONG 30N88W OVER SE LOUISIANA NEAR 19N91W. HEAVY SHOWERS WITH EMBEDDED THUNDERSTORMS ARE MOVING N FROM 27N TO INLAND OVER THE N GULF COAST BETWEEN PANAMA CITY FLORIDA AND ATCHAFALAYA BAY LOUISIANA. BROAD UPPER HIGH CONTINUES TO DOMINATE THE GULF CENTERED NEAR 25N90W. UPPER DIFFLUENCE TO THE E OF THE UPPER HIGH IS ENHANCING THE ACTIVITY ASSOCIATED WITH THE FRONTAL BOUNDARY. RETURN SURFACE FLOW CONVERGING WITH UPPER LEVEL FLOW AROUND THE UPPER HIGH IS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 22N-27N BETWEEN 90W-95W. LOW LEVEL POPCORN TYPE SHOWERS WITH POSSIBLE ISOLATED THUNDERSTORMS DOT THE SE GULF S OF 26N E OF 84W THROUGH THE FLORIDA STRAITS. CARIBBEAN SEA... AN UPPER LEVEL SHEAR AXIS BISECTS THE CENTRAL CARIBBEAN EXTENDING ACROSS E HISPANIOLA/MONA PASSAGE TO THE BORDER OF NICARAGUA/COSTA RICA. DRY STABLE AIR ON NE UPPER FLOW FROM THE W ATLC IS DRAWING INTO THE CARIBBEAN W OF THIS AXIS WHILE MOIST TROPICAL AIR WITH SW UPPER FLOW IS TO THE E ACCOMPANIED BY CLUSTERS OF SCATTERED SHOWERS/THUNDERSTORMS MAINLY S OF 18N FROM 66W-77W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 120/150 NM ALONG THE COAST OF PANAMA W OF 80W AND COSTA RICA DUE TO THE CLOSE PROXIMITY OF THE ITCZ AXIS AS IT ENTERS THE E PACIFIC REGION. 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 80W. 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 32N58W SW TO 29N68W 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 OVER LAKE OKEECHOBEE AND INTO THE W ATLC ALONG 28N69W TO NEAR 29N63W ENHANCING SCATTERED SHOWERS/THUNDERSTORMS N OF 27N W OF 77W TO OVER THE SE US. A SURFACE RIDGE IS BUILDING BEHIND THE FRONTAL BOUNDARY ANCHORED BY A 1028 MB HIGH OFF THE VIRGINIA COAST WELL N OF THE REGION. AN UPPER SHEAR AXIS EXTENDS FROM THE CENTRAL ATLC NEAR 23N52W INTO THE CARIBBEAN OVER E HISPANIOLA/MONA PASSAGE WITH A SWATH OF DRY STABLE AIR OVER THE REMAINDER OF THE W ATLC WITHIN 425 NM NW OF THE SHEAR AXIS INTO THE CARIBBEAN. A CUT-OFF UPPER LOW IS IN THE E/CENTRAL ATLC NEAR 27N40W WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS COVERS THE AREA FROM 26N-31N BETWEEN 39W-43W. WEAK SURFACE RIDGE COVERS THE CENTRAL ATLC ANCHORED BY A 1023 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 26N37W TO 22N48W WITH SCATTERED SHOWERS AND WIDELY ISOLATED THUNDERSTORMS WITHIN 150/180 NM OF THE SURFACE TROUGH E OF 40W. 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 21N FROM THE E CARIBBEAN TO THE CAPE VERDE ISLANDS. $$ WALLACE