000 AXPZ20 KNHC 290941 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SUN JUN 29 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0845 UTC. ...SPECIAL FEATURES... TROPICAL DEPRESSION FOUR-E IS CENTERED NEAR 15.3N 108.8W OR ABOUT 460 NM...850 KM S OF THE SOUTHERN TIP OF BAJA CALIFORNIA AT 29/0600Z MOVING W-NW OR 290 DEGREES AT 14 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. MAXIMUM SUSTAINED WIND SPEEDS ARE 30 KT WITH GUSTS TO 40 KT. THE DEPRESSION IS FORECAST TO BECOME A TROPICAL STORM LATER TODAY. A BAND OF NUMEROUS MODERATE TO STRONG CONVECTION IS NOTED TO THE NW OF CENTER FROM 15N TO 18N BETWEEN 109W AND 115W. NUMEROUS MODERATE TO ISOLATED STRONG CONVECTION IS WITHIN 90 NM OF CENTER. THE 0448 UTC ASCAT PASS SHOWS THE STRONGEST WINDS OF 30 KT IN THE LARGE SCALE SOUTHWESTERLY FLOW SE AND AWAY FROM THE CENTER...WITH AN AREA OF FRESH TO STRONG WINDS OF 20-25 KT TO THE NE OF THE CENTER BETWEEN THE DEPRESSION AND THE PACIFIC COAST OF MEXICO. THE SAME ASCAT PASS SUGGESTS THAT THE SYSTEM DOES NOT YET HAVE STRONG WINDS VERY CLOSE TO THE CENTER...AND THESE WINDS ARE BELOW TROPICAL STORM FORCE. PLEASE SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS. A SMALL AREA OF LOW PRES...ANALYZED NEAR 11.5N97.5W ON THE 0600 UTC SURFACE MAP...IS PRODUCING DISORGANIZED SHOWERS AND TSTMS. SOME DEVELOPMENT OF THIS SYSTEM IS POSSIBLE OVER THE NEXT FEW DAYS WHILE IT MOVES W-NW OR NW AT AROUND 10 KT. THE LATEST TROPICAL WEATHER OUTLOOK GIVES THIS SYSTEM A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. ...TROPICAL WAVE... A TROPICAL WAVE EXTENDS FROM THE SW GULF OF MEXICO NEAR 21N96W INTO THE EPAC TO NEAR 12.5N97W. A CLUSTER OF MODERATE TO STRONG CONVECTION IS OVER THE GULF OF TEHUANTEPEC. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION CAN BE FOUND ON EITHER SIDE OF THE WAVE AXIS MAINLY N OF 13N BETWEEN 96W AND 101W. THE WAVE IS JUST N OF THE AFOREMENTIONED SMALL AREA OF LOW PRES. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 07N78W TO 04N87W TO 1009 MB LOW PRES NEAR 11.5N97.5W THEN RESUMES WEST OF T.D. FOUR-E FROM 12N110W TO 10N120W TO 09N130W TO 07N140W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS SEEN FROM 09N TO 12N BETWEEN 110W AND 116W. ...DISCUSSION... ALOFT...AN UPPER-LEVEL CYCLONIC CIRCULATION IS OVER THE NW CORNER OF THE DISCUSSION AREA NEAR 29N139W WITH ASSOCIATED TROUGH EXTENDING SW TO 26N140W. A LARGE ANTICYCLONIC CIRCULATION REMAINS CENTERED NEAR 25N128W WITH A RIDGE EXTENDING NE TO BEYOND 32N122W AND ANOTHER RIDGE EXTENDING FROM THE SAME ANTICYCLONE SW TO 18N140W. WATER VAPOR IMAGERY INDICATES MODERATE TO STRONG MID/UPPER LEVEL SUBSIDENCE AND IMPLIED DRY AIR MASS COVERING MOST OF THE AREA N OF A LINE FROM 23N110W TO 12N120W TO 12N140W. AN INVERTED TROUGH EXTENDS FROM SOUTHERN BAJA CALIFORNIA NEAR 24N111W TO 14N124W. A DIFFLUENT PATTERN ALOFT...ASSOCIATED WITH ANOTHER ANTICYCLONE LOCATED ALONG THE COAST OF MEXICO NEAR 17N100W...IS ENHANCING CONVECTION ASSOCIATED WITH TROPICAL DEPRESSION FOUR-E AND THE SMALL AREA OF LOW PRES PREVIOUSLY MENTIONED. UPPER DIFFLUENCE IS ALSO HELPING TO INDUCE CONVECTION OVER THE ISTHMUS AND GULF OF TEHUANTEPEC. AT THE SURFACE...A 1026 MB HIGH PRES CENTERED NEAR 38N140W EXTENDS A RIDGE SE TO NEAR T.D. FOUR-E. MAINLY MODERATE TRADES ARE SEEN PER SCATTEROMETER DATA BETWEEN THE SOUTHERN PERIPHERY OF THE RIDGE AND THE MONSOON TROUGH. PRES GRADIENT BETWEEN THE RIDGE AND LOWER PRES OVER NORTHERN MEXICO IS PRODUCING MODERATE TO LOCALLY FRESH WINDS JUST OFF THE BAJA CALIFORNIA PENINSULA. CROSS EQUATORIAL SW SWELL...WITH PERIODS IN THE 17-18 SECOND RANGE...HAS REACHED MOST OF THE COAST OF CENTRAL AMERICA AND SE MEXICO. ADDITIONAL PULSES OF SW SWELL WILL PROPAGATE ACROSS THE SOUTH-CENTRAL WATERS LATE SUN INTO MON...BUILDING SEAS UP TO 10 FT S OF A LINE FROM 3.4S95W TO 03N102W TO 04N115W TO 00N122W BY MON NIGHT. GAP WINDS... FRESH TO STRONG NE-E WINDS ARE EXPECTED ACROSS THE GULF OF PAPAGAYO DURING THE NEXT 48 HOURS...BUT MAINLY FROM 0600 TO 1200 UTC...WITH BUILDING SEAS TO 8 FT THROUGH AND DOWNWIND OF THE GULF. $$ GR