000 AXNT20 KNHC 131043 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN AUG 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 1015 UTC. ...TROPICAL WAVES... TROPICAL WAVE OFF THE W COAST OF AFRICA IS ALONG 22W S OF 19N MOVING W 10-15 KT. WELL DEFINED MID LEVEL INVERTED V SIGNATURE CURVATURE IS ON SATELLITE IMAGERY WITH NO DEEP CONVECTION. ISOLATED SHOWERS ARE FROM 11N-17N BETWEEN 18W-21W. TROPICAL WAVE IS ALONG 55W/56W S OF 19N WITH A 1011 MB SURFACE LOW ALONG THE WAVE NEAR 13N MOVING W 10-15 KT. WELL DEFINED INVERTED V SIGNATURE CURVATURE IS ON SATELLITE IMAGERY. THE LOW CLOUD SWIRL IS NOW BENEATH THE SCATTERED MODERATE/ISOLATED STRONG CONVECTION THAT IS WITHIN 75/90 NM OF LINE FROM 16N55W TO 12N61W. ALTHOUGH WAVE CONTINUES TO BE EMBEDDED WITHIN A DRY ENVIRONMENT SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 75 NM OF LINE 19N49W-16N55W. TROPICAL WAVE IN THE CARIBBEAN IS ALONG 81W/82W S OF 20N MOVING W NEAR 15-20 KT. WAVE IS TO THE W OF AN UPPER LEVEL LOW FORCING ANY SHOWER ACTIVITY TO THE W OF THE WAVE. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 12N14W 7N35W 6N46W 11N61W ACROSS THE N PORTION OF SOUTH AMERICA AND THROUGH THE SW CARIBBEAN ALONG 10N80W INTO THE E PACIFIC REGION. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 3N-12N BETWEEN 23W-55W. ...DISCUSSION... GULF OF MEXICO... WEATHER ACROSS THE GULF FOR THE MOST PART CONTINUES TO BE QUIET WITH THE ONLY EXCEPTION IN THE BAY OF CAMPECHE. A SURFACE RIDGE STRETCHES FROM THE ATLC TO OVER FLORIDA WITH A 1015 MB HIGH IN THE E GULF NEAR 27N85W. THIS IS KEEPING WINDS LIGHT ACROSS THE ENTIRE GULF. IN THE UPPER LEVELS...THE UPPER LEVEL LOW REMAINS OVER NE MEXICO AND THE W GULF. AN UPPER RIDGE IN THE E PACIFIC REGION NOW EXTENDS ACROSS THE FAR S MEXICO AND THE BAY OF CAMPECHE WITH ENOUGH DIFFLUENCE TO GENERATE SCATTERED MODERATE/ ISOLATED STRONG CONVECTION S OF 19N FROM 94W-96W. OTHERWISE THE GULF REMAINS CLEAR. CARIBBEAN SEA... AN UPPER LEVEL LOW DOMINATES THE W CARIBBEAN CENTERED OFF THE COAST OF NICARAGUA NEAR 15N82W COVERING THE AREA W OF 75W WITH THE TROPICAL WAVE BENEATH THIS FEATURE. SCATTERED SHOWERS DOT THE W CARIBBEAN FROM 2N-20N W OF 78W. THE E CARIBBEAN IS DOMINATED BY AN UPPER RIDGE ANCHORED IN THE TROPICAL ATLC JUST E OF THE LEEWARD ISLANDS. THIS RIDGE IS ENHANCING THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVE ALONG 55W/56W AND BRINGING SCATTERED SHOWERS TO THE WINDWARD AND ABC ISLANDS WITH HEAVY RAIN AND THUNDERSTORMS TO THE ISLAND OF BARBADOS. THE REMAINDER OF THE CARIBBEAN IS DRY IN SPITE OF THE ITCZ AXIS EXTENDING ACROSS N PORTION OF SOUTH AMERICA AND ACROSS THE SW CARIBBEAN. ATLANTIC OCEAN... A DEEP LAYERED TROUGH COVERS MOST OF THE E US AND INTO THE W ATLC N OF 29N W OF 55W. ASSOCIATED FRONTAL BOUNDARY EXTENDS INTO THE REGION JUST E OF BERMUDA TO A 1011 MB LOW OFF THE COAST OF NE FLORIDA NEAR 31N78W CONTINUING W JUST S OF JACKSONVILLE FLORIDA THEN PULLING UP OVER THE SE US. SCATTERED SHOWERS/ THUNDERSTORMS ARE FROM 28N-32N BETWEEN 66W-80W AND N OF 30N TO THE FRONTAL BOUNDARY FROM 58W-66W. AN UPPER HIGH IS CENTERED JUST TO THE S OF THIS TROUGH OFF THE COAST OF FLORIDA NEAR 27N78W WITH THE RIDGE AXIS STRETCHING E TO 50W. AN UPPER HIGH IS E OF THE LEEWARD ISLANDS NEAR 16N58W ENHANCING SHOWERS/ CONVECTION ASSOCIATED WITH THE TROPICAL WAVE ALONG 55W/56W IN SPITE OF THE VERY DRY ENVIRONMENT. ELSEWHERE...BESIDES FOR THE TROPICAL WAVES AND ITCZ RELATED CONVECTION...VERY LITTLE UNSETTLED WEATHER IS OCCURRING IN THE ATLC BASIN. THERE ARE SEVERAL UPPER LEVEL FEATURES...NONE OF WHICH ARE CAUSING MUCH INSTABILITY. A WEAKENING UPPER LEVEL LOW IS NOW LOCATED JUST N OF THE SOUTHERN MOST BAHAMAS NEAR 23N71W AND ANOTHER WEAK UPPER LOW IS NEAR 27N37W. THE E ATLC CONTINUES TO BE DOMINATED BY AN UPPER RIDGE EXTENDING W FROM AFRICA. DRY/STABLE AIR LIES ABOVE THE MAJORITY OF THE AREA. AT THE SURFACE...WEAKENING HIGH PRESSURE RIDGE CONTINUES ACROSS THE ATLC WITH A SERIES OF EMBEDDED HIGHS...1019 MB HIGHS NEAR 31N25W AND 26N47W AND A 1018 MB HIGH NEAR 24N63W. $$ WALLACE