000 AXPZ20 KNHC 300311 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC THU JUN 30 2011 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0245 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS W ACROSS COSTA RICA TO 12N93W...THEN RESUMES FROM THE COAST OF MEXICO NEAR 18N103W TO A WEAK 1010 MB SURFACE LOW NEAR 12N111W THEN CONTINUES THROUGH 11N120W TO 08N126W. BROAD CYCLONIC FLOW ASSOCIATED WITH TROPICAL STORM ARLENE LOCATED IN THE SW GULF OF MEXICO WAS NOTED ALONG THE COAST OF CENTRAL AMERICA AND MEXICO BETWEEN 92W AND 108W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 08N126W TO 06N140W. SCATTERED MODERATE TO STRONG WITHIN 60-90 NM OF THE COAST OF COSTA RICA BETWEEN 83W AND 86W...AND WITHIN 90 NM OF LINE 11N98W TO 08N107W. SCATTERED MODERATE WITHIN 90 NM OF THE COAST OF MEXICO BETWEEN 100W AND 105W. ...DISCUSSION... A SHARP UPPER LEVEL TROUGH EXTENDS FROM AN UPPER LEVEL CYCLONE OVER CENTRAL CALIFORNIA TO 32N120W THROUGH 28N125W TO A COL NEAR 29N133W...THEN CONTINUED TO A MID LEVEL CYCLONE CENTERED NEAR 27N139W. THE TROUGH WAS SUPPORTING A DISSIPATING COLD FRONT WHICH EXTENDED FROM THE SOUTHERN CALIFORNIA COAST THROUGH 30N122W TO 28N140W. THIS FRONT WAS ONLY ACCOMPANIED BY A 15 KT W TO NW WIND SHIFT. AN UPPER ANTICYCLONE IS JUST W OF THE AREA NEAR 18N150W WITH AN UPPER RIDGE EXTENDING NE JUST TO THE W OF THE DISCUSSION AREA. AN UPPER LEVEL ANTICYCLONE IS CENTERED OVER NORTHERN OLD MEXICO NEAR 30N105W WITH AN UPPER RIDGE EXTENDING SW TO NEAR 20N134W. AN UPPER LEVEL TROUGH EXTENDS FROM THE EXTREME NW GULF OF MEXICO SW ACROSS NORTHERN OLD MEXICO. THE UPPER TROUGH THEN TURNS ABRUPTLY SW INTO ANOTHER UPPER CYCLONE OVER THE PACIFIC NEAR 21N115W THAT IS MOVING W ALONG THE SOUTHERN PERIPHERY OF THE SUBTROPICAL RIDGE. THIS TROUGH EFFECTIVELY SEPARATES THE UPPER FLOW ASSOCIATED WITH THE SUBTROPICAL RIDGE FROM ANOTHER BROAD RIDGE OVER THE TROPICS. THE PARENT UPPER ANTICYCLONE IS IN THE VICINITY OF TROPICAL STORM ARLENE IN THE SW GULF OF MEXICO WITH A RIDGE EXTENDING W ACROSS MEXICO TO THE E PACIFIC NEAR 18N113W. DENSE MID TO UPPER LEVEL DEBRIS MOISTURE FROM TROPICAL STORM ARLENE...NUMEROUS CLUSTERS OF STRONG CONVECTION OVER SE MEXICO...GUATEMALA AND EL SALVADOR AND CONVECTION DESCRIBED ABOVE FANS OUT OVER THE DISCUSSION AREA FROM 03N TO 23N BETWEEN 80W AND 110W. THE UPPER LEVELS ARE VERY DRY TO THE N OF 15N W OF 110W INCLUDING WESTERN ARIZONA AND EXTREME SE CALIFORNIA...AND OVER THE DEEP TROPICS TO THE S OF 16N BETWEEN 114W AND 142W. ELSEWHERE AT THE SURFACE...A BROAD RIDGE WITH BROKEN TO OVERCAST STRATOCUMULUS CLOUDS COVERS THE MARINE AREA TO THE N OF 15N W OF BAJA CALIFORNIA BRIDGING THROUGH THE DISSIPATING COLD FRONT NOTED ABOVE. A SMALL AREA OF 20 KT NE TRADES ARE OBSERVED S OF THE RIDGE FROM 07N TO 11N W OF 135W...BUT ARE EXPECTED TO DIMINISH WITHIN 24 HOURS. THE PRESSURE GRADIENT HAS TIGHTENED N OF THE RIDGE RESULTING IN A SWATH OF NW 20 KT WINDS TO THE N OF 25N ALONG THE NORTHERN COAST OF THE BAJA CALIFORNIA PENINSULA. THESE WINDS ARE EXPECTED TO EXPAND SOMEWHAT IN AREA THROUGH FRI. AS TROPICAL STORM ARLENE IN THE GULF OF MEXICO MOVES W OVER INTERIOR CENTRAL MEXICO WESTERLY LOW LEVEL WINDS WILL INCREASE TO 20 KT OVER THE PACIFIC WATERS FROM 15N TO 20N BETWEEN 98W AND 105W ON THU...AND FROM 16N TO 20N BETWEEN 101W AND 107W ON FRI WITH SEAS BUILDING TO 9 FT BY FRI. $$ COBB 000 AXPZ20 KNHC 300311 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC THU JUN 30 2011 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0245 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS W ACROSS COSTA RICA TO 12N93W...THEN RESUMES FROM THE COAST OF MEXICO NEAR 18N103W TO A WEAK 1010 MB SURFACE LOW NEAR 12N111W THEN CONTINUES THROUGH 11N120W TO 08N126W. BROAD CYCLONIC FLOW ASSOCIATED WITH TROPICAL STORM ARLENE LOCATED IN THE SW GULF OF MEXICO WAS NOTED ALONG THE COAST OF CENTRAL AMERICA AND MEXICO BETWEEN 92W AND 108W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 08N126W TO 06N140W. SCATTERED MODERATE TO STRONG WITHIN 60-90 NM OF THE COAST OF COSTA RICA BETWEEN 83W AND 86W...AND WITHIN 90 NM OF LINE 11N98W TO 08N107W. SCATTERED MODERATE WITHIN 90 NM OF THE COAST OF MEXICO BETWEEN 100W AND 105W. ...DISCUSSION... A SHARP UPPER LEVEL TROUGH EXTENDS FROM AN UPPER LEVEL CYCLONE OVER CENTRAL CALIFORNIA TO 32N120W THROUGH 28N125W TO A COL NEAR 29N133W...THEN CONTINUED TO A MID LEVEL CYCLONE CENTERED NEAR 27N139W. THE TROUGH WAS SUPPORTING A DISSIPATING COLD FRONT WHICH EXTENDED FROM THE SOUTHERN CALIFORNIA COAST THROUGH 30N122W TO 28N140W. THIS FRONT WAS ONLY ACCOMPANIED BY A 15 KT W TO NW WIND SHIFT. AN UPPER ANTICYCLONE IS JUST W OF THE AREA NEAR 18N150W WITH AN UPPER RIDGE EXTENDING NE JUST TO THE W OF THE DISCUSSION AREA. AN UPPER LEVEL ANTICYCLONE IS CENTERED OVER NORTHERN OLD MEXICO NEAR 30N105W WITH AN UPPER RIDGE EXTENDING SW TO NEAR 20N134W. AN UPPER LEVEL TROUGH EXTENDS FROM THE EXTREME NW GULF OF MEXICO SW ACROSS NORTHERN OLD MEXICO. THE UPPER TROUGH THEN TURNS ABRUPTLY SW INTO ANOTHER UPPER CYCLONE OVER THE PACIFIC NEAR 21N115W THAT IS MOVING W ALONG THE SOUTHERN PERIPHERY OF THE SUBTROPICAL RIDGE. THIS TROUGH EFFECTIVELY SEPARATES THE UPPER FLOW ASSOCIATED WITH THE SUBTROPICAL RIDGE FROM ANOTHER BROAD RIDGE OVER THE TROPICS. THE PARENT UPPER ANTICYCLONE IS IN THE VICINITY OF TROPICAL STORM ARLENE IN THE SW GULF OF MEXICO WITH A RIDGE EXTENDING W ACROSS MEXICO TO THE E PACIFIC NEAR 18N113W. DENSE MID TO UPPER LEVEL DEBRIS MOISTURE FROM TROPICAL STORM ARLENE...NUMEROUS CLUSTERS OF STRONG CONVECTION OVER SE MEXICO...GUATEMALA AND EL SALVADOR AND CONVECTION DESCRIBED ABOVE FANS OUT OVER THE DISCUSSION AREA FROM 03N TO 23N BETWEEN 80W AND 110W. THE UPPER LEVELS ARE VERY DRY TO THE N OF 15N W OF 110W INCLUDING WESTERN ARIZONA AND EXTREME SE CALIFORNIA...AND OVER THE DEEP TROPICS TO THE S OF 16N BETWEEN 114W AND 142W. ELSEWHERE AT THE SURFACE...A BROAD RIDGE WITH BROKEN TO OVERCAST STRATOCUMULUS CLOUDS COVERS THE MARINE AREA TO THE N OF 15N W OF BAJA CALIFORNIA BRIDGING THROUGH THE DISSIPATING COLD FRONT NOTED ABOVE. A SMALL AREA OF 20 KT NE TRADES ARE OBSERVED S OF THE RIDGE FROM 07N TO 11N W OF 135W...BUT ARE EXPECTED TO DIMINISH WITHIN 24 HOURS. THE PRESSURE GRADIENT HAS TIGHTENED N OF THE RIDGE RESULTING IN A SWATH OF NW 20 KT WINDS TO THE N OF 25N ALONG THE NORTHERN COAST OF THE BAJA CALIFORNIA PENINSULA. THESE WINDS ARE EXPECTED TO EXPAND SOMEWHAT IN AREA THROUGH FRI. AS TROPICAL STORM ARLENE IN THE GULF OF MEXICO MOVES W OVER INTERIOR CENTRAL MEXICO WESTERLY LOW LEVEL WINDS WILL INCREASE TO 20 KT OVER THE PACIFIC WATERS FROM 15N TO 20N BETWEEN 98W AND 105W ON THU...AND FROM 16N TO 20N BETWEEN 101W AND 107W ON FRI WITH SEAS BUILDING TO 9 FT BY FRI. $$ COBB