000 AXNT20 KNHC 121046 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT FRI OCT 12 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. ...SPECIAL FEATURE... TROPICAL DEPRESSION FIFTEEN IS CENTERED NEAR 30.0N 49.4W AT 12/0900 UTC MOVING E AT 3 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1011 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT5/WTNT25 KNHC FOR MORE DETAILS. SCATTERED MODERATE CONVECTION IS TO THE E OF THE LOW LEVEL CENTER FROM 30N-32N BETWEEN 46W-49W. AN UPPER LEVEL TROUGH HAS MOVED OVER THE SYSTEM WITH THE UPPER LOW NEAR 30N50W THUS WEAKENING THE SHEAR. LITTLE OR NO STRENGTHENING IS EXPECTED AND THE SYSTEM IS EXPECTED TO BECOME A REMNANT LOW BY SAT. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 66W S OF 17N MOVING W NEAR 10 KT. WEAK SATELLITE SIGNATURE WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 16N TO THE COAST OF VENEZUELA BETWEEN 65W-69W INCLUDING THE ABC ISLANDS. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 12N14W 7N37W 9N62W. SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 120 NM N OF THE ITCZ AXIS FROM 20W-26W WITH CLUSTERS OF SIMILAR CONVECTION FROM 6N-14N BETWEEN 14W-20W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 2N-9N BETWEEN 26W-30W. CLUSTERS OF SCATTERED MODERATE CONVECTION IS WITHIN 120 NM OF THE ITCZ AXIS FROM 36W-39W AND WITHIN 120 NM N OF THE AXIS FROM 55W-58W. DISCUSSION... GULF OF MEXICO... BROAD DEEP LAYERED TROUGH COVERS MUCH OF THE GULF N OF 22N ANCHORED BY A LARGE UPPER LOW OVER CANADA AND EXTENDS INTO THE W ATLC WITH THE ASSOCIATED COLD FRONT IN W ATLC BECOMING STATIONARY OVER CENTRAL FLORIDA NEAR LAKE OKEECHOBEE AND DISSIPATING IN THE CENTRAL GULF NEAR 26N91W. SCATTERED SHOWERS/REMNANT ISOLATED THUNDERSTORMS ARE IN THE CENTRAL GULF FROM 25N-27N BETWEEN 87W-91W. BROAD UPPER RIDGE EXTENDS WESTWARD ACROSS S MEXICO FROM AN UPPER HIGH OVER BELIZE PRODUCING UPPER DIFFLUENCE ACROSS THE FAR S GULF GENERATING SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS ACROSS S MEXICO AND ALONG THE IMMEDIATE COASTAL WATERS IN THE BAY OF CAMPECHE W OF 94W. OTHERWISE THE REMAINDER OF THE GULF IS UNDER DRY6 SOMEWHAT STABLE AIR THUS MOSTLY CLEAR SKIES. CARIBBEAN SEA... A PERSISTENT 1003 MB LOW REMAINS INLAND OVER N GUATEMALA WITH A SURFACE TROUGH EXTENDING NE ACROSS N BELIZE AND CENTRAL CUBA NEAR 22N81W INTO THE W ATLC. SCATTERED/NUMEROUS STRONG CONVECTION IS FROM 15N-20N BETWEEN 85W-90W INCLUDING ALL OF BELIZE. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 90/120 NM OF THE REMAINDER OF THE SURFACE TROUGH TO THE COAST OF CUBA. A BROAD UPPER RIDGE EXTENDS FROM AN UPPER HIGH OVER BELIZE INTO THE CARIBBEAN ALONG 18N81W THEN NE ACROSS E CUBA INTO THE W ATLC COVERING THE CARIBBEAN W OF 65W. UPPER DIFFLUENCE AND AN ABUNDANCE OF TROPICAL MOISTURE ARE GENERATING CLUSTERS OF SCATTERED STRONG CONVECTION N OF 17N FROM 76W-82W INCLUDING A PORTION OF CUBA AND ALL OF JAMAICA. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE STREAMING N OVER PUERTO RICO AND THE E DOMINICAN REPUBLIC DUE TO THE TROPICAL WAVE IN THE AREA. LOW LEVEL AND UPPER LEVEL CONVERGENCE IS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ACROSS THE S CARIBBEAN S OF 11N. ATLANTIC OCEAN... THE DEEP LAYERED TROUGH OVER THE E US AND THE GULF OF MEXICO EXTENDS OVER THE W ATLC W OF A LINE FROM CENTRAL CUBA TO JUST W OF BERMUDA WITH THE ASSOCIATED COLD FRONT EXTENDING THROUGH 32N73W TO 28N78W WHERE IT BECOMES STATIONARY ACROSS FLORIDA NEAR LAKE OKEECHOBEE AND DISSIPATES IN THE GULF OF MEXICO. DUE TO DRY CONTINENTAL AIR FILTERING E OFF THE COAST OF THE US IS LIMITING TO LOW LEVEL SHOWERS WITHIN 60 NM OF THE FRONTAL BOUNDARY. THE UPPER RIDGE FROM THE CARIBBEAN EXTENDS ACROSS E CUBA E OF BERMUDA TO BEYOND 32N62W WITH ENOUGH DIFFLUENCE TO GENERATE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 150/175 NM OF LINE FROM ACROSS E CUBA NEAR 21N76W TO BEYOND 32N64W. A SURFACE TROUGH FROM THE CARIBBEAN EXTENDS ACROSS CENTRAL CUBA NEAR 23N80W TO 29N70W AND IS BETWEEN THE UPPER TROUGH TO THE W AND THE UPPER RIDGE TO THE E. AN UPPER LEVEL LOW IS IN THE W/CENTRAL ATLC NEAR 29N51W WITH THE UPPER TROUGH EXTENDING S TO NEAR 26N54W. T.D. FIFTEEN IS ALONG THE E SIDE OF THIS UPPER TROUGH. AN UPPER TROUGH COVERS THE REMAINDER OF THE ATLC EXTENDING FROM AN UPPER LOW OVER THE CANARY ISLANDS NEAR 29N18W INTO THE E TROPICAL ATLC JUST W OF THE CAPE VERDE ISLANDS TO NEAR 17N35W. A SMALL SURFACE 1010 MB LOW IS CENTERED JUST W OF THE CANARY ISLANDS NEAR 29N19W WITH SCATTERED SHOWERS ARE WITHIN 90 NM NE OF THE SURFACE LOW. A WEAK 1018 MB HIGH IS CENTERED NEAR 29N38W. $$ WALLACE