000 AXNT20 KNHC 130527 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0445 UTC. ...TROPICAL WAVES... TROPICAL WAVE OFF THE W COAST OF AFRICA IS ALONG 20W S OF 19N MOVING W 10 KT. WELL DEFINED MID LEVEL INVERTED V SIGNATURE CURVATURE IS ON SATELLITE IMAGERY BUT WAVE HAS LOST ALL DEEP CONVECTION AS IT MOVES FURTHER OFF THE COAST OF AFRICA. ISOLATED SHOWERS ARE WITHIN 90 NM EITHER SIDE OF THE WAVE AXIS FROM 9N-14N. TROPICAL WAVE IS ALONG 53W/54W 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 ALTHOUGH THE LOW CLOUD SWIRL IS NOT AS EVIDENT AS EARLIER IN THE DAY SAT. WAVE CONTINUES TO BE EMBEDDED IN A DRY ENVIRONMENT LIMITING ANY ORGANIZED CONVECTION. HOWEVER...SCATTERED SHOWERS ARE WITHIN 120 NM OF LINE FROM 17N50W-15N57W. TROPICAL WAVE IN THE CARIBBEAN IS ALONG 80W 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 13N14W 8N39W 12N52W ACROSS THE N PORTION OF SOUTH AMERICA ALONG 10N71W THROUGH THE SW CARIBBEAN NEAR 12N84W INTO THE E PACIFIC REGION. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120/150 NM N OF THE AXIS FROM 55W-60W. SCATTERED CLUSTERS OF SIMILAR CONVECTION ARE WITHIN 180 NM OF THE AXIS FROM 22W-39W AND FROM 4N-10N BETWEEN 41W-53W. ...DISCUSSION... GULF OF MEXICO... QUIET WEATHER CONTINUES ACROSS THE GULF TONIGHT WITH THE SURFACE RIDGE STRETCHING FROM THE ATLC ACROSS FLORIDA TO A 1014 MB HIGH IN THE CENTRAL GULF NEAR 27N89W. 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 BUT HAS BECOME LESS ACTIVE. HOWEVER SOME SHOWERS/ISOLATED THUNDERSTORMS ARE INLAND OVER S MEXICO BRINGING MID/UPPER LEVEL MOISTURE ALONG THE COAST FROM THE W BAY OF CAMPECHE TO S TEXAS. HOWEVER WITH THE DRY CONDITIONS IN PLACE THE SHOWERS SHOULD REMAIN INLAND TONIGHT. CARIBBEAN SEA... AN UPPER LEVEL LOW DOMINATES THE W CARIBBEAN CENTERED OFF THE COAST OF NICARAGUA NEAR 14N83W COVERING THE AREA W OF 74W WITH THE TROPICAL WAVE BENEATH THIS FEATURE. SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS DOT THE W CARIBBEAN N OF 18N W OF 77W AND W OF 82W ACROSS THE REMAINDER OF THE W CARIBBEAN. THE E CARIBBEAN IS DOMINATED BY MID/UPPER RIDGE ANCHORED IN THE TROPICAL ATLC JUST E OF THE LEEWARD ISLANDS. THIS IS BRINGING ISOLATED SHOWERS TO THE WINDWARD ISLANDS AND APPROACHING THE ABC ISLANDS OFF THE COAST OF VENEZUELA. 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 PORTION OF THE US AND INTO THE W ATLC JUST N OF THE REGION. A FRONTAL BOUNDARY IS BEGINNING TO DIP INTO THE REGION JUST S OF BERMUDA ALONG 31N TO A WEAK 1012 MB LOW JUST OFF THE COAST OF GEORGIA/SOUTH CAROLINA PULLING UP INTO THE SE US. SCATTERED MODERATE/STRONG CONVECTION IS COLLOCATED WITH THE SURFACE LOW COVERING THE AREA N OF 29N FROM 76W TO THE COAST OF FLORIDA/GEORGIA. SCATTERED SHOWERS/THUNDERSTORMS ARE S OF THE FRONTAL BOUNDARY TO 29N FROM 60W-76W. 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 17N58W ENHANCING SHOWERS ASSOCIATED WITH THE TROPICAL WAVE ALONG 53W/54W 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 23N70W 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...HIGH PRESSURE RIDGE CONTINUES ACROSS THE ATLC WITH A SERIES OF EMBEDDED HIGHS...1020 MB HIGHS NEAR 29N29W AND 26N45W AND A 1018 MB HIGH NEAR 24N61W. $$ WALLACE