000 AXNT20 KNHC 251743 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE JUN 25 2013 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA... CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA... NORTHERN SECTIONS OF SOUTH AMERICA...AND 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 10N34W TO 4N36W MOVING WEST AT 15-20 KT. THE WAVE IS LOW-AMPLITUDE AND MAINLY EMBEDDED WITHIN THE ITCZ. SCATTERED MODERATE CONVECTION IS FROM 4N-7N BETWEEN 32W-38W. MODEL GUIDANCE INDICATES THAT THE WAVE WILL AMPLIFY IN ABOUT 24- 48 HOURS. TROPICAL WAVE IS MOVING THROUGH THE LESSER ANTILLES ALONG 19N62W TO 12N61WM MOVING WNW NEAR 20 KT. THE WAVE COINCIDES WITH A SURGE OF DEEP LAYER MOISTURE PRESENT IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE CONVECTION IS MAINLY EAST OF THE AXIS FROM 16N-19N BETWEEN 58W-63W. ISOLATED MODERATE CONVECTION IS FROM 12N-15N BETWEEN 57W-60W. TROPICAL WAVE IS MOVING THROUGH THE NORTH CENTRAL CARIBBEAN AND ACROSS HISPANIOLA FROM 24N67W TO 16N72W MOVING WNW AT AROUND 15 KT. THE WAVE ALIGNS WITH A SURGE OF DEEP LAYER MOISTURE PRESENT IN TOTAL PRECIPITABLE WATER IMAGERY. AN UPPER LEVEL LOW IS ALSO PROVIDING DIFFLUENT FLOW NEAR THE NORTHERN PORTION OF THE WAVE WHICH IS HELPING ENHANCE CONVECTION. SCATTERED MODERATE CONVECTION IS FROM 22N-25N BETWEEN 62W-67W. ISOLATED MODERATE CONVECTION IS FROM 20N-23N BETWEEN 67W-71W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH THE COAST OF NORTHERN SENEGAL NEAR 16N16W TO 11N23W. THE ITCZ BEGINS NEAR 11N23W AND CONTINUES ALONG 7N32W 4N43W. ISOLATED MODERATE/STRONG CONVECTION IS FROM 7N-10N BETWEEN 12W-19W. SCATTERED MODERATE CONVECTION IS FROM 4N- 6N BETWEEN 40W-46W. ...DISCUSSION... THE GULF OF MEXICO... FAIR WEATHER IS THROUGHOUT THE GULF OF MEXICO TODAY AS SURFACE RIDGING COVERS THE AREA EXTENDING FROM HIGH PRESSURE IN THE ATLC. WINDS ARE EAST TO SOUTHEAST AT 5-10 KT REACHING 15 KT OVER THE WESTERN GULF. A FEW ISOLATED SHOWERS/THUNDERSTORMS ARE BUILDING OVER THE FLORIDA PANHANDLE LIKELY ASSOCIATED WITH UPPER LEVEL DIFFLUENCE AROUND AN UPPER LEVEL TROUGH THAT SINKS INTO THE NORTHEAST GULF. ISOLATED SHOWERS/THUNDERSTORMS ARE ALSO OVER THE EASTERN FLORIDA PENINSULA. ELSEWHERE ALOFT...DRY NORTHERLY FLOW COVERS THE WESTERN GULF...WHILE AN UPPER LEVEL RIDGE COVERS THE SE GULF CENTERED NEAR 25N83W. AN UPPER LEVEL LOW IS ALSO CENTERED OVER THE YUCATAN PENINSULA NEAR 19N89W. THE DRY AIR ALOFT IS HELPING SUPPORT THE FAIR SURFACE CONDITIONS. SURFACE RIDGING IS EXPECTED TO REMAIN THE DOMINANT SYNOPTIC FEATURE FOR THE NEXT SEVERAL DAYS. MOISTURE NEAR A TROPICAL WAVE OVER THE CENTRAL CARIBBEAN MAY IMPACT THE SE GULF NEAR THE END OF THE WEEK. THE CARIBBEAN SEA... MOIST SOUTHWESTERLY FLOW COVERS MUCH OF THE CARIBBEAN TODAY WITH AN UPPER LEVEL LOW CENTERED OVER THE YUCATAN PENINSULA NEAR 19N89W...AND AN UPPER LEVEL RIDGE CENTERED OVER THE SE CARIBBEAN NEAR 13N64W. A FEW PATCHES OF SHOWERS/THUNDERSTORMS HAVE FORMED OVER THE NW CARIBBEAN. SCATTERED SHOWERS/THUNDERSTORMS ARE IN THE SW CARIBBEAN ASSOCIATED WITH THE MONSOON TROUGH ALONG 10N EXTENDING FROM COSTA RICA TO NORTHERN COLOMBIA. TWO TROPICAL WAVES ARE ALSO MOVING THROUGH THE BASIN. THE FIRST IS ACROSS HISPANIOLA NEAR 71W. MOST OF THE SHOWERS/THUNDERSTORMS ARE NORTH OF THE ISLAND IN THE ATLC WHERE AN UPPER LEVEL TROUGH IS ENHANCING ACTIVITY. THE SECOND WAVE IS MOVING THROUGH THE LESSER ANTILLES NEAR 61W. SCATTERED SHOWERS ARE EAST OF 63W MAINLY NORTH OF 15N. TRADEWIND FLOW OF 15-20 KT DOMINATES MUCH OF THE AREA. EXPECT BOTH WAVES TO CONTINUE MOVING WEST. THE EASTWARD WAVE WILL LIKELY BRING MORE MOISTURE TO THE BASIN. HISPANIOLA... DESPITE THE PRESENCE OF A WAVE OVER HISPANIOLA NEAR 71W...ONLY A FEW WIDELY ISOLATED SHOWERS/THUNDERSTORMS HAVE FORMED OVER THE ISLAND. MOST OF THE ACTIVITY NEAR THE WAVE IS TO THE NORTH BEING INFLUENCED BY AN UPPER TROUGH. THE WAVE WILL CONTINUE MOVING WEST AND SHOULD BE WEST OF HAITI WITHIN THE NEXT 12-24 HOURS. THERE IS AN AREA OF DRY AIR EAST OF THE WAVE THAT WILL REACH THE ISLAND SHORTLY BEFORE THE NEXT TROPICAL WAVE WILL BRING HIGHER MOISTURE BEGINNING WEDNESDAY. THIS SECOND WAVE IS LIKELY TO CAUSE MORE CONVECTIVE ACTIVITY OVER THE ISLAND THAN THE CURRENT ONE. THE ATLANTIC OCEAN... BROAD SURFACE RIDGING COVER THE WEST AND CENTRAL ATLC ANCHORED BY A 1023 MB HIGH NEAR 32N64W. DRY AIR IS PRESENT THROUGH MUCH OF THE AREA EXCEPT NEAR A TROPICAL WAVE JUST EAST OF THE SE BAHAMAS. AN UPPER LEVEL LOW NEAR 27N70W IS ALSO PROVIDING DIFFLUENT FLOW OVER THE WAVE. THIS COMBINATION IS SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS FROM 22N-25N BETWEEN 62W- 67W...AND FROM 20N-22N BETWEEN 67W-71W. A SECOND WAVE NEAR THE LESSER ANTILLES IS SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS EAST OF THE ISLANDS FROM 12N-20N BETWEEN 56W-62W. A WEAK SURFACE TROUGH IS EAST OF THE HIGH CENTER ALONG 32N49W TO 28N53W. ISOLATED SHOWERS ARE WITHIN 120 NM SE OF THE AXIS. THE REMAINDER OF THE BASIN IS DOMINATED BY BROAD RIDGING AROUND A 1033 MB HIGH NEAR 45N23W. ALOFT...A BROAD UPPER TROUGH COVERS THE AREA CENTERED NEAR 34N36W. BROAD UPPER RIDGING COVERS THE EXTREME TROPICAL ATLC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON