000 AXNT20 KNHC 131104 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT FRI OCT 13 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 36W/37W SOUTH OF 20N DRIFTING WEST. A 1010 MB LOW PRESSURE CENTER IS ALONG THE WAVE. THIS WAVE IS MOVING TOWARD AN AREA WHICH NOW IS OCCUPIED BY A MIDDLE TO UPPER LEVEL TROUGH JUST WEST OF 40W. STRONG SHOWERS AND THUNDERSTORMS FROM 14N TO 16N BETWEEN 33W AND 36W. ISOLATED MODERATE SHOWERS ELSEWHERE FROM 10N TO 20N BETWEEN 30W AND 40W...AND FROM 22N TO 23N BETWEEN 36W AND 37W. AN EASTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 67W/68W SOUTH OF 22N MOVING WEST 10 KT. THE 1010 MB LOW PRESSURE CENTER WHICH WAS ALONG THE WAVE FOR PARTS OF THE LAST 12 HOURS NOW IS NEAR 22N65W WHILE THE WAVE HAS CONTINUED ON ITS OWN TO THE WEST. WIDELY SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE IN CLUSTERS FROM 18N TO 25N BETWEEN 58W AND 65W. ISOLATED MODERATE SHOWERS FROM 16N TO 18N BETWEEN 62W AND 65W...AND FROM 14N TO 16N BETWEEN 65W AND 69W. A WESTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 82W/83W SOUTH OF 20N MOVING WEST 10 KT. THIS WAVE IS MOVING THROUGH AN AREA OF AN UPPER LEVEL RIDGE. MIDDLE TO UPPER LEVEL DRY AIR COVERS THE CARIBBEAN SEA PRACTICALLY EVERYWHERE WEST OF 70W. NO DEEP CONVECTIVE PRECIPITATION IS WITH THIS WAVE. AN EASTERN PACIFIC OCEAN TROPICAL WAVE IS ALONG 101W/102W SOUTH OF 18N MOVING WEST 10 TO 15 KT. ONE CLUSTER OF STRONG SHOWERS AND THUNDERSTORMS IS ALONG THE MEXICO COAST FROM 17N TO 18N BETWEEN 102W AND 104W. ONE OTHER CLUSTER IS IN THE WESTERN HALF OF THE GULF OF TEHUANTEPEC AND ANOTHER ONE IS FROM 15N TO 16N BETWEEN 98W AND 99W. GRADUAL DEVELOPMENT OF THIS SYSTEM IS POSSIBLE DURING THE NEXT COUPLE OF DAYS AS IT MOVES WESTWARD SLOWLY. LOCALLY HEAVY RAINS ARE POSSIBLE ALONG THE COAST AND IN NEARBY MOUNTAINOUS AREAS DUE TO THE CLOSE PROXIMITY OF THE SYSTEM TO MAINLAND MEXICO. ...THE ITCZ... 10N13W 8N24W 9N33W 8N40W 7N52W 8N62W. ISOLATED MODERATE SHOWERS TO LOCALLY STRONG THUNDERSTORMS ARE FROM 3N TO 12N BETWEEN AFRICA AND 45W. ISOLATED MODERATE SHOWERS FROM 5N TO 12N BETWEEN 45W AND 60W. ...DISCUSSION... THE GULF OF MEXICO... A COLD FRONT CROSSES NORTHERN FLORIDA TO THE FLORIDA PANHANDLE. A STATIONARY FRONT CONTINUES FROM THE FLORIDA PANHANDLE TO SOUTHERN LOUISIANA TO A 1009 MB LOW PRESSURE CENTER IN SOUTH TEXAS...TO FAR WEST TEXAS. A WEAK SURFACE TROUGH RUNS FROM THE FLORIDA KEYS TO SOUTH CENTRAL TEXAS. UPPER LEVEL WESTERLY FLOW COVERS THE GULF WATERS. THIS WESTERLY FLOW IS ASSOCIATED WITH LARGE-SCALE UPPER LEVEL ANTICYCLONIC FLOW. ISOLATED SHOWERS AND THUNDERSTORMS ARE NORTH OF 26N WEST OF 90W...AND JUST OFF THE NORTHERN COAST OF THE YUCATAN PENINSULA. THE CARIBBEAN SEA... AN UPPER LEVEL RIDGE RUNS FROM THE SOUTH CENTRAL MEXICO EASTWARD TO THE GREATER ANTILLES. MIDDLE TO UPPER LEVEL DRY AIR IS WEST OF A LINE FROM 30N66W 15N70W 10N76W. CLOUDY SKIES AND AN UPPER LEVEL RIDGE ARE TO THE EAST OF THE DRY AIR. SCATTERED STRONG SHOWERS AND THUNDERSTORMS GO FROM NORTHWESTERN VENEZUELA TO NORTHERN COLOMBIA...PROBABLY IN THE ITCZ. THE ATLANTIC OCEAN... A DEEP LAYER TROUGH RUNS FROM THE UPPER MIDWEST OF THE INTERIOR UNITED STATES OF AMERICA...ACROSS THE CAROLINAS...AND INTO THE COASTAL SECTIONS EAST OF THE U.S.A. NORTH OF 27N WEST OF 65W. UPPER LEVEL WESTERLY FLOW CROSSES FLORIDA...FROM THE GULF OF MEXICO ANTICYCLONIC FLOW...AND REACHES 66W/67W FROM 27N TO 31N. THIS FLOW THEN TURNS CYCLONIC...TO THE SOUTHWEST...AND IT HEADS TOWARD THE MONA PASSAGE AND THE OPEN WATERS OF THE CARIBBEAN SEA. ANOTHER RIDGE IS ALONG 16N65W IN THE CARIBBEAN SEA...TO 24N60W TO 32N59W. UPPER LEVEL NORTHWESTERLY FLOW ON THE EASTERN SIDE OF THIS RIDGE THEN HEADS TOWARD THE TROUGH WHICH IS JUST WEST OF THE 36W/37W TROPICAL WAVE. A SURFACE TROUGH PASSES THROUGH 32N66W 27N70W 24N75W TO THE STRAITS OF FLORIDA. AN ATLANTIC FRONTAL BOUNDARY IS FROM 30N TO 32N BETWEEN 30W AND 60W. AN UPPER LEVEL TROUGH REACHES ITS BASE NEAR 28N37W. ISOLATED MODERATE SHOWERS ARE WITHIN 30 NM ON EITHER SIDE OF 32N30W 30N35W 29N41W. A MIDDLE TO UPPER LEVEL TROUGH IS ALONG A LINE FROM THE AZORES TO THE CANARY ISLANDS TO THE CAPE VERDE ISLANDS. $$ MT