000 AXPZ20 KNHC 210231 TWDEP AXPZ20 KNHC DDHHMM TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC SAT JUN 21 2014 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 0215 UTC. ...SPECIAL FEATURE... A 1008 MB SURFACE LOW IS ANALYZED NEAR 10.5N110W ALONG A LOW LEVEL TROUGH ORIENTATED NE TO SW FROM 15N105W TO 07N113W. AN UPPER ANTICYCLONE IS CENTERED NEAR 09N106W WITH AN UPPER RIDGE EXTENDING W ACROSS THE SURFACE LOW TO A CREST NEAR 11N111W. THE ASSOCIATED UPPER DIFFLUENCE IS ENHANCING SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 90 NM OF THE CENTER. CYCLONIC 15-20 KT WINDS ARE OBSERVED 240 NM OVER THE SE SEMICIRCLE WITH SEAS OF 5-8 FT. THE LOW IS EXPECTED TO MOVE N TO NEAR 14N110W LATE SAT AND NEAR 16N110W LATE SUN WITH THE POSSIBILITY OF TROPICAL CYCLONE FORMATION. ...TROPICAL WAVES... A ILL-DEFINED TROPICAL WAVE IS ANALYZED TO THE N OF 13N ALONG 95.5W. AN UPPER ANTICYCLONE IS CENTERED NEAR 09N106W WITH AN UPPER RIDGE EXTENDING NE ACROSS CENTRAL MEXICO. THIS RESULTS IN UPPER NORTHWESTERLY FLOW ACROSS THE LOWER LEVEL TROPICAL WAVE WHICH IS ADVECTING DRY UPPER AIR SOUTHWARD SUPPRESSING CONVECTION NEAR THE WAVE AXIS. THE UPPER LEVELS ARE MOIST FURTHER TO THE W UNDER THE UPPER ANTICYCLONIC ENVELOP. THUS...THE WAVE MAY HAVE SOME POTENTIAL TO ENHANCE CONVECTION AGAIN AS IT PASSES ALONG THE PACIFIC COAST OF MEXICO BETWEEN 96- 103W OVER THE NEXT COUPLE OF DAYS. ...TROPICAL LOWS... VISIBLE SATELLITE IMAGERY INDICATES THE SURFACE LOW PREVIOUSLY POSITIONED AT 11N129W IS CENTERED A LITTLE E NEAR NEAR 11N128W AND IS ESTIMATED AT 1010 MB. UPPER LEVEL RIDGING TO THE N HAS PUSHED THE ASSOCIATED CONVECTION WELL W OF THE LOW LEVEL CENTER WITH ONLY SCATTERED MODERATE CONVECTION CURRENTLY DECAYING WITHIN 75 NM OF 13.5N132.5W. SURFACING RIDGING TO THE N IS SUPPORTING N-NE 15-25 KT WINDS WITHIN 240 NM OVER THE NW SEMICIRCLE OF THE LOW WITH SEAS SEAS OF 6-8 FT. THE LOW IS FORECAST TO MOVE W TO NEAR 11N130W LATE SAT AND NEAR 10N132W LATE SUN. WINDS AND SEAS ARE FORECAST TO DIMINISH/SUBSIDE LATE SUN. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS NW FROM PACIFIC COAST OF COLOMBIA AT 08N78W ACROSS THE PACIFIC COAST OF PANAMA TO THE PACIFIC COAST OF COSTA RICA AT 10N85W...THEN CONTINUES W TO 10N96W...THEN NW TO 12N104W...THEN SW THROUGH AN EMBEDDED 1008 MB SURFACE LOW AT 10.5N110W. THE MONSOON TROUGH CONTINUES NW TO 12N123W...THEN SW THROUGH AN EMBEDDED 1010 MB SURFACE LOW AT 11N128W WITH THE MONSOON TROUGH STILL CONTINUING SW TO 08N131W WHERE SCATTEROMETER WINDS INDICATE A TRANSITION TO ITCZ WHICH CONTINUES WSW TO BEYOND 06N140W. EXCEPT AS PREVIOUSLY DESCRIBED NEAR THE EMBEDDED SURFACE LOWS... SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED TO THE N OF 05N WITHIN 60 NM OF COAST OF COLOMBIA. SIMILAR CONVECTION IS NOTED OVER AND TO THE N OF THE MONSOON TROUGH WITHIN 150 NM EITHER SIDE OF A LINE FROM 17N101W TO 12N106W...AND S OF THE MONSOON TROUGH WITHIN 120 NM EITHER SIDE OF A LINE FROM 07N111W TO 12N117W. ISOLATED MODERATE AND STRONG CONVECTION IS OBSERVED ELSEWHERE WITHIN AREA FROM 04-10N BETWEEN 81-106W...AND FROM 07- 13N BETWEEN 119-123W. ...DISCUSSION... AN UPPER CYCLONE IS CENTERED OVER THE SOUTHERN GULF OF CALIFORNIA AT 24N110W WITH A UPPER TROUGH EXTENDING S TO A BASE OVER THE DEEP TROPICS AT 12N115W. AN AREA OF UPPER DIFFLUENCE IS INDUCED E OF THIS TROUGH AND UNDER AN UPPER RIDGE WHICH HAS BEEN ENHANCING CONVECTION ALONG THE MONSOON TROUGH AND AN EMBEDDED LOW PREVIOUSLY DESCRIBED NEAR 10.5N110W. STRONG SOUTHERLY UPPER FLOW IS ADVECTING THE DEBRIS MOISTURE N ACROSS MEXICO WITHIN 300 NM EITHER SIDE OF A LINE FROM 12N107W TO 22N100W TO 30N100W WHERE THE MOISTURE FANS OUT ACROSS THE S CENTRAL CONUS AND EVENTUALLY TURNS E ACROSS THE SOUTHERN MISSISSIPPI VALLEY. AN UPPER ANTICYCLONE NEAR 16N129W HAS AN UPPER RIDGE EXTENDING E TO A CREST OVER THE SW CONUS. DEBRIS MOISTURE FROM PREVIOUS CONVECTION ALONG THE WESTERN SEGMENT OF THE MONSOON TROUGH IS ADVECTED N AND NE AROUND THE W PERIPHERY OF THE ANTICYCLONE TO NEAR 29N127W. A SURFACE RIDGE EXTENDS FROM 32N133W TO NEAR 15N107W. NW-N WINDS AT 10-15 KT...SEAS OF 3-6 FT IN MIXED NNW AND LONG PERIOD SSE SWELL...ARE OBSERVED N OF RIDGE ACROSS THE SUBTROPICAL WATERS FROM 26-32N BETWEEN 125W AND THE NORTHERN BAJA CALIFORNIA PENINSULA. THE GRADIENT WILL TIGHTEN ON SAT INCREASING THE FLOW TO 15-20 KT ACROSS THE WATERS N OF 30N BETWEEN 120-125W WITH SEAS BUILDING TO 7-8 FT ON SUN NIGHT. GUIDANCE IS SUGGESTING THE GRADIENT WILL RELAX AGAIN LATE SUN WITH SEAS SUBSIDING TO 5-7 FT. LONG PERIOD N AND S SWELL WITH COMBINED SEAS OF 6-9 FT HAS MOVED INTO THE SOUTHERN WATERS TO THE S OF 01N BETWEEN 98-120W. THE SOUTHERLY SWELL IS BEGINNING TO DAMPER WITH SEAS EXPECTED TO SUBSIDE TO 6-7 FT ACROSS THESE SOUTHERN WATERS EARLY SAT. $$ NELSON