000 AXNT20 KNHC 271056 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT WED JUN 27 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... A TROPICAL WAVE IS ALONG 37W S OF 17N MOVING W 10-15 KT. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED S OF 10N WITHIN 150 NM W AND WITHIN 180 NM E OF THE WAVE AXIS. A TROPICAL WAVE IS ALONG 74W S OF 24N MOVING W AT 10-15 KT. UPPER DIFFLUENCE BETWEEN AN UPPER TROUGH NEAR THE BAHAMAS AND AN UPPER RIDGE OVER THE NE CARIBBEAN IS ENHANCING CONVECTION IN THE STRAITS OF FLORIDA AND THE NORTHERN BAHAMAS. SUBSIDENCE OVER THE CENTRAL CARIBBEAN IS SUPPRESSING CONVECTION WITH ONLY TRADE WIND CUMULUS NOTED. A SURGE IN LOW LEVEL TRADE WIND FLOW ACCOMPANIES THIS WAVE AS WELL AS A LARGE AREA OF SAHARAN DUST...WHICH HAS ITS WESTERN EDGE ALONG 73W AND EXTENDS E ACROSS THE WINDWARDS. A TROPICAL WAVE EXTENDS FROM NICARAGUA TO THE WESTERN TIP OF CUBA ALONG 84/85W MOVING W AT 10-15 KT. SCATTERED CONVECTION IS NOTED ACROSS NICARAGUA AND NEAR WESTERN CUBA. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 11N15W 7N27W 7N44W 8N59W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS LOCATED WITHIN 120 NM OF THE AXIS BETWEEN 18W AND 54W. ...DISCUSSION... THE GULF OF MEXICO... AN UPPER ANTICYCLONE IS CENTERED NEAR 19N105W. NLY ANTICYCLONIC FLOW EXTENDS FROM CENTRAL MEXICO TO THE WESTERN GULF OF MEXICO. AN UPPER TROUGH EXTENDS S ACROSS THE CENTRAL GULF FROM 30N83W THROUGH A UPPER LEVEL CYCLONE NEAR 21N87W TO 16N88W. THIS UPPER TROUGH HAS INDUCED A LOW LEVEL TROUGH FROM 28N86W TO 21N87W WHICH IS MOVING SLOWLY W. STRONG CONVECTION IS LIKELY TO DEVELOP TODAY ACROSS...AND JUST NORTH OF...THE YUCATAN CHANNEL. THE CARIBBEAN SEA... AN UPPER TROUGH EXTENDS S FROM THE NW BAHAMAS TO AN UPPER CYCLONE NEAR THE YUCATAN PENINSULA AND S TO BELIZE. AN UPPER ANTICYCLONE OVER NW VENEZUELA IS PRODUCING SOUTHWESTERLY UPPER LEVEL FLOW OVER THE CARIBBEAN. DEBRIS MOISTURE IS BEING ADVECTED ENE INTO THE SUBTROPICAL SW ATLC. A BAND OF DRY UPPER AIR IS INDICATED ACROSS THE CENTRAL CARIBBEAN SUPPRESSING CONVECTION. BRISK TRADE WINDS PREVAIL ACROSS THE REGION. AREAS OF TRADE WIND CUMULUS AND BRIEF LIGHT SHOWERS WILL CONTINUE TODAY. SAHARAN DUST SPREADING W ACROSS THE AREA MAY REDUCE VISIBILITY AT TIMES...BUT CONDITIONS SHOULD IMPROVE LATER TODAY. THE ATLANTIC OCEAN... AN UPPER CYCLONE IS CENTERED OVER EASTERN FLORIDA NEAR 27N80W. A WEAK SURFACE TROUGH IS EVIDENT OVER THE NW BAHAMAS. BOTH SYSTEMS ARE SHIFTING WESTWARD. AS UPPER DIFFLUENCE E OF THE UPPER LOW MOVES OVER THE NW BAHAMAS AND FLORIDA...CONDITIONS WILL BECOME FAVORABLE FOR INCREASED AFTERNOON CONVECTION. THE TROPICAL WAVE ALONG 74W WILL MOVE THROUGH THE BAHAMAS AND STRAITS OF FLORIDA THROUGH THURSDAY AND INCREASE THE CHANCE FOR RAIN E OF ITS AXIS. AN UPPER RIDGE EXTENDING N FROM THE E CARIBBEAN INTO THE SW ATLC BETWEEN 73W AND 58W IS ADVECTING MOISTURE INTO THE SUBTROPICAL ATLC UNDER THE RIDGE. AN UPPER TROUGH EXTENDS ACROSS THE CENTRAL ATLC FROM 31N47W THROUGH AN UPPER CYCLONE NEAR 20N51W TO 10N57W. DRY AIR ALOFT ACCOMPANIES THIS TROUGH. ANOTHER UPPER TROUGH IS NOTED OVER THE FAR E ATLC ALONG 31N17W TO 23N27W. AN UPPER RIDGE EXTENDS W OFF THE AFRICAN COAST ALONG 17N TO 20W. $$ MUNDELL