000 AXPZ20 KNHC 301552 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1545 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM NW COSTA RICA TO 14N92W PARALLELING THE COAST OF CENTRAL AMERICA. THE BROAD LOW LEVEL CYCLONIC CIRCULATION FROM TROPICAL STORM ARLENE...CURRENTLY MAKING LANDFALL ON THE E COAST OF MEXICO...INTERRUPTS THE E PACIFIC MONSOON GYRE WITH THE MONSOON TROUGH AXIS RESUMING AT 16N96W AND EXTENDING SW THROUGH AN EMBEDDED SURFACE LOW AT 12N109W THEN CONTINUING SW TO NEAR 10N123W WHERE LOW LEVEL WINDS INDICATE A TRANSFORMATION TO AN INTERTROPICAL CONVERGENCE ZONE WHICH CONTINUES SW TO BEYOND 06N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN 150 NM EITHER SIDE OF A LINE FROM 04N77W TO 10N86W AND ANOTHER LINE FROM 08N88W TO 07N106W. THE CONVECTION NEAR 05N80W IS INTENSIFYING. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS DISSIPATING WITHIN 120 NM OF CENTRAL AMERICAN COAST FROM 85W TO 91W AND BUT SEEMS TO BE INCREASING WITHIN 150 NM OF THE MEXICAN COAST FROM 93W TO 107W. ...DISCUSSION... A QUASI STATIONARY UPPER LEVEL TROUGH EXTENDS SW THE NORTHERN BAJA CALIFORNIA PENINSULA INTO AN UPPER CYCLONE AT 23N127W... THEN CONTINUES WNW THROUGH 25N132W TURNING ABRUPTLY SW INTO ANOTHER UPPER CYCLONE AT 21N140W. THE ASSOCIATED SURFACE FRONT HAS DISSIPATED. AN UPPER ANTICYCLONE IS AT 20N131W WITH AN UPPER RIDGE EXTENDING SW TO A CREST AT 20N138W. AN UPPER CYCLONE IS AT 22N115W AND MOVING WESTWARD. THE UPPER ANTICYCLONE FROM TROPICAL STORM ARLENE IS CENTERED 23N104W WITH AN UPPER RIDGE EXTENDING SW TO 15N112W. AN UPPER CYCLONE IS OVER HAITI WITH AN UPPER TROUGH EXTENDING SW TO OVER PANAMA. CONVECTION FLARED LAST NIGHT OVER NORTHERN OLD MEXICO WITH THE DEBRIS MOISTURE SPREADING N OVER THE BORDER OF NEW MEXICO AND ARIZONA...BUT SHOULD SOON EVAPORATE AS THE SOURCE CONVECTION HAS COMPLETELY DISSIPATED. ISOLATED CLUSTERS OF CONVECTION HAVE BEEN FLARING ALONG THE MONSOON TROUGH AND ITCZ BETWEEN 112W AND 132W. THE DEBRIS MOISTURE IS OBSERVED WITHIN 150 NM OF A LINE FROM 10N115W TO 09N131W. OTHERWISE THE UPPER LEVELS APPEAR VERY DRY TO THE N OF 15N W OF 110W...AND S OF 15N W OF 132W. UPPER LEVEL ANTICYCLONIC FLOW...AND GENERAL UPPER DIFFLUENCE... DOMINATES THE REMAINDER OF THE DISCUSSION AREA. DENSE UPPER LEVEL DEBRIS MOISTURE...FROM TROPICAL STORM ARLENE AND THE PREVIOUSLY DESCRIBED MONSOON TROUGH CONVECTION...FANS OUT OVER THE DISCUSSION AREA FROM 05N TO 23N E OF 109W. ELSEWHERE AT THE SURFACE...A BROAD RIDGE ACCOMPANIED BY BROKEN TO OVERCAST STRATOCUMULUS CLOUDS...COVERS THE MARINE AREA N OF 14N TO THE W OF 115W. A SMALL AREA OF 20 KT NE TRADES ARE OBSERVED SW OF THE RIDGE FROM 07N TO 11N W OF 135W...BUT ARE EXPECTED TO DIMINISH TODAY. THE PRESSURE GRADIENT NE OF THE RIDGE WILL MAINTAIN A SWATH OF NORTHWESTERLY 15 TO 20 KT WINDS OVER THE WATERS N OF 25N WITHIN 180 NM W OF THE BAJA CALIFORNIA PENINSULA FOR A COUPLE MORE DAYS. AS TROPICAL STORM ARLENE CONTINUES W OVER INTERIOR CENTRAL MEXICO WESTERLY LOW LEVEL WINDS WILL INCREASE TONIGHT AND FRI TO 20 TO 25 KT OVER THE PACIFIC WATERS FROM 12N TO 20N BETWEEN 100W AND 110W...THEN DIMINISH ON SAT. NORTHERLY SWELL RESULTING IN COMBINED SEAS TO 8 FT...WILL PROPAGATE S INTO THE PACIFIC WATERS TO THE N OF 28N BETWEEN 120W AND 132W BEGINNING FRI NIGHT. $$ NELSON 000 AXPZ20 KNHC 301552 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1545 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM NW COSTA RICA TO 14N92W PARALLELING THE COAST OF CENTRAL AMERICA. THE BROAD LOW LEVEL CYCLONIC CIRCULATION FROM TROPICAL STORM ARLENE...CURRENTLY MAKING LANDFALL ON THE E COAST OF MEXICO...INTERRUPTS THE E PACIFIC MONSOON GYRE WITH THE MONSOON TROUGH AXIS RESUMING AT 16N96W AND EXTENDING SW THROUGH AN EMBEDDED SURFACE LOW AT 12N109W THEN CONTINUING SW TO NEAR 10N123W WHERE LOW LEVEL WINDS INDICATE A TRANSFORMATION TO AN INTERTROPICAL CONVERGENCE ZONE WHICH CONTINUES SW TO BEYOND 06N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN 150 NM EITHER SIDE OF A LINE FROM 04N77W TO 10N86W AND ANOTHER LINE FROM 08N88W TO 07N106W. THE CONVECTION NEAR 05N80W IS INTENSIFYING. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS DISSIPATING WITHIN 120 NM OF CENTRAL AMERICAN COAST FROM 85W TO 91W AND BUT SEEMS TO BE INCREASING WITHIN 150 NM OF THE MEXICAN COAST FROM 93W TO 107W. ...DISCUSSION... A QUASI STATIONARY UPPER LEVEL TROUGH EXTENDS SW THE NORTHERN BAJA CALIFORNIA PENINSULA INTO AN UPPER CYCLONE AT 23N127W... THEN CONTINUES WNW THROUGH 25N132W TURNING ABRUPTLY SW INTO ANOTHER UPPER CYCLONE AT 21N140W. THE ASSOCIATED SURFACE FRONT HAS DISSIPATED. AN UPPER ANTICYCLONE IS AT 20N131W WITH AN UPPER RIDGE EXTENDING SW TO A CREST AT 20N138W. AN UPPER CYCLONE IS AT 22N115W AND MOVING WESTWARD. THE UPPER ANTICYCLONE FROM TROPICAL STORM ARLENE IS CENTERED 23N104W WITH AN UPPER RIDGE EXTENDING SW TO 15N112W. AN UPPER CYCLONE IS OVER HAITI WITH AN UPPER TROUGH EXTENDING SW TO OVER PANAMA. CONVECTION FLARED LAST NIGHT OVER NORTHERN OLD MEXICO WITH THE DEBRIS MOISTURE SPREADING N OVER THE BORDER OF NEW MEXICO AND ARIZONA...BUT SHOULD SOON EVAPORATE AS THE SOURCE CONVECTION HAS COMPLETELY DISSIPATED. ISOLATED CLUSTERS OF CONVECTION HAVE BEEN FLARING ALONG THE MONSOON TROUGH AND ITCZ BETWEEN 112W AND 132W. THE DEBRIS MOISTURE IS OBSERVED WITHIN 150 NM OF A LINE FROM 10N115W TO 09N131W. OTHERWISE THE UPPER LEVELS APPEAR VERY DRY TO THE N OF 15N W OF 110W...AND S OF 15N W OF 132W. UPPER LEVEL ANTICYCLONIC FLOW...AND GENERAL UPPER DIFFLUENCE... DOMINATES THE REMAINDER OF THE DISCUSSION AREA. DENSE UPPER LEVEL DEBRIS MOISTURE...FROM TROPICAL STORM ARLENE AND THE PREVIOUSLY DESCRIBED MONSOON TROUGH CONVECTION...FANS OUT OVER THE DISCUSSION AREA FROM 05N TO 23N E OF 109W. ELSEWHERE AT THE SURFACE...A BROAD RIDGE ACCOMPANIED BY BROKEN TO OVERCAST STRATOCUMULUS CLOUDS...COVERS THE MARINE AREA N OF 14N TO THE W OF 115W. A SMALL AREA OF 20 KT NE TRADES ARE OBSERVED SW OF THE RIDGE FROM 07N TO 11N W OF 135W...BUT ARE EXPECTED TO DIMINISH TODAY. THE PRESSURE GRADIENT NE OF THE RIDGE WILL MAINTAIN A SWATH OF NORTHWESTERLY 15 TO 20 KT WINDS OVER THE WATERS N OF 25N WITHIN 180 NM W OF THE BAJA CALIFORNIA PENINSULA FOR A COUPLE MORE DAYS. AS TROPICAL STORM ARLENE CONTINUES W OVER INTERIOR CENTRAL MEXICO WESTERLY LOW LEVEL WINDS WILL INCREASE TONIGHT AND FRI TO 20 TO 25 KT OVER THE PACIFIC WATERS FROM 12N TO 20N BETWEEN 100W AND 110W...THEN DIMINISH ON SAT. NORTHERLY SWELL RESULTING IN COMBINED SEAS TO 8 FT...WILL PROPAGATE S INTO THE PACIFIC WATERS TO THE N OF 28N BETWEEN 120W AND 132W BEGINNING FRI NIGHT. $$ NELSON