000 AXPZ20 KNHC 220255 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC MON JUN 22 2015 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 0230 UTC. ...TROPICAL WAVES... A TROPICAL WAVE HAS ENTERED THE FAR EASTERN PORTION OF THE AREA WITH ITS AXIS ALONG 83W N OF 08N TO ACROSS CENTRAL COSTA RICA AND THE EASTERN SECTOR OF HONDURAS AND NICARAGUA...WITH AN APPROXIMATE WESTWARD MOTION OF 10 KT. SSMI TPW IMAGERY INDICATES THAT THERE IS ABUNDANT MOISTURE S OF 12N ALONG THE WAVE...WITH DRY AIR N OF 12N. THE WAVE HAS INTERACTED WITH LOCAL SEA BREEZE EFFECTS AND LOCAL TRADE CONVERGENCE OVER COSTA RICA AND PANAMA TO ENHANCE SCATTERED STRONG CONVECTION ACROSS THOSE AREAS. SIMILAR ACTIVITY IS S OF THE WAVE WITHIN 30 NM OF 05N86W. A TROPICAL WAVE AXIS IS ALONG 96W FROM 06N-15N MOVING W AT 10-15 KT. EARLIER SCATTERED MODERATE CONVECTION NOTED IN ASSOCIATION WITH THIS HAS DIMINISHED...AND ONLY ISOLATED SHOWERS AND TSTMS ARE NOTED W OF THE WAVE TO 100W FROM 08N TO 10N. A TROPICAL WAVE AXIS IS ALONG 113W FROM 08N-15N MOVING W 15 KT. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM OF 08N112W. INSTABILITY BEING PROVIDED AN UPPER LEVEL LOW IN THE VICINITY OF THE WAVE IS RESULTING IN SCATTERED SHOWERS AND ISOLATED TSTMS ELSEWHERE WITHIN 180 NM OF THE WAVE AXIS. A TROPICAL WAVE AXIS IS ALONG 133W/134W FROM 05N-13N MOVING W ABOUT 15 KT. THIS WAVE IS UNDER BROAD ANTICYCLONIC FLOW ALOFT ...AND IS EMBEDDED IN A VERY DEEP MOIST LOW-LEVEL ATMOSPHERIC ENVIRONMENT AS OBSERVED ON THE SSMI TPW SATELLITE ANIMATION. THE WAVE IS ENHANCING CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION MAINLY S OF THE ITCZ AS DESCRIBED BELOW. SCATTERED SMALL CLUSTERS OF MODERATE CONVECTION ARE SEEN WITHIN 30 NM OF 11N132W...AND WITHIN 30 NM OF 10N131.5W. THE UPPER ANTICYCLONIC FLOW SHOULD SUPPORT THE CURRENT ONGOING CONVECTION THROUGH THE NEXT 8 HOURS AS THE WAVE CONTINUES WESTWARD TO JUST W OF 140W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... SCATTEROMETER DATA INDICATES THAT A WEAK MONSOON TROUGH EXTENDS W OFF THE COAST OF COLOMBIA FROM 07N78W TO 06N85W TO 06N92W WHERE THE ITCZ IS IDENTIFIED AND CONTINUES W TO 7N102W TO 09N112W...THEN RESUMES AT 07N116W TO 08N124W TO 08N132W TO 08N140W. SCATTERED MODERATE/ISOLATED STRONG WITHIN 180 NM S OF ITCZ W OF 138W. SCATTERED MODERATE FROM 08N TO 13N BETWEEN 101W AND 105W. ...DISCUSSION... UPPER LEVELS...THE FLOW PATTERN ASSOCIATED WITH AN ANTICYCLONE OVER FAR EASTERN ARIZONA CONTINUES TO DOMINATE THE NORTHERN PART OF THE AREA MAINLY N OF 20N W OF 110W. ANOTHER ANTICYCLONE IS FARTHER S NEAR 13N123W. A SHARP UPPER-LEVEL TROUGH EXTENDS FROM EASTERN TEXAS SW TO N CENTRAL MEXICO...AND CONTINUES W FROM THERE AS A SHEAR AXIS TO A SMALL UPPER LEVEL LOW LOCATED NEAR 25N116W. A TROUGH EXTENDS FROM THIS LOW TO NEAR 18N112W...THEN BECOMES A SHEAR AXIS TO AN ELONGATED UPPER LOW AT 08N111W. WATER VAPOR SATELLITE IMAGERY SHOWS MODERATE TO STRONG SUBSIDENCE WITH RESULTANT DRY AIR COVERING MUCH OF THE FORECAST AREA N OF 15N W OF 110W. NORTHERLY FLOW PERSISTS OVER SOUTHEASTERN MEXICO...THE GULF OF TEHUANTEPEC AND THE REMAINDER OF THE AREA N OF 10N BETWEEN 91W-100W DUE TO THE COMBINATION OF AN ANTICYCLONE OVER MEXICO NEAR 20N102W...AND A BROAD UPPER LOW CENTERED OVER THE EASTERN YUCATAN PENINSULA. BROAD RIDGING COVERS THE FAR EASTERN PACIFIC E OF ABOUT 87W...INCLUDING COSTA RICA AND PANAMA AND ALSO THE FAR SW PORTION WHERE AN ANTICYCLONE IS SITUATED AT 05N135W. UPPER DIFFLUENCE ASSOCIATED WITH THIS RIDGE IS HELPING TO ALSO SUSTAIN CLUSTERS OF STRONG CONVECTION OVER COSTA RICA AND PANAMA AS DESCRIBED ABOVE IN ASSOCIATION WITH THE TROPICAL WAVE ALONG 83W. THE RIDGING IS ALSO AIDING A FEW CLUSTERS OF SCATTERED MODERATE CONVECTION OVER AND ALONG THE COAST OF COLOMBIA FROM 03N TO 08N. AT THE SURFACE...A NEARLY STATIONARY 1022 MB HIGH IS ANALYZED AT 31N131W WITH A RIDGE SE TO 21N120W. HIGH PRES COVERS THE AREA N OF 18N W OF 120W WHILE A WEAK TROUGH EXTENDS FROM 23N117W TO 21N122W. THE PRES GRADIENT BETWEEN THE RIDGE AND LOWER PRES IN THE VICINITY OF THE ITCZ IS MAINTAINING MODERATE TO LOCALLY FRESH NE-E TRADES OVER THE WESTERN PART OF THE FORECAST REGION N OF THE ITCZ FROM 10N-17N W OF 133W AS HIGHLIGHTED BY SCATTEROMETER DATA FROM SUN AFTERNOON. SEAS WITHIN THIS AREA OF TRADES ARE IN THE RANGE OF 6-8 FT PRIMARILY IN MIXED NE AND SW SWELLS. NWP MODELS SUGGEST THAT WEAK HIGH PRES WILL REMAIN OVER THE FAR NW PART OF THE AREA DURING THE NEXT 48 HOURS WHILE A SURFACE TROUGH IS FORECAST TO PERSIST OVER NORTHERN BAJA CALIFORNIA AND THE NE WATERS. LONG PERIOD CROSS-EQUATORIAL MIXED SE AND SW SWELLS ARE PRODUCING SEAS TO 8 FT S OF A LINE FROM 02N140W TO 04N120W TO 01S105W TO 01S94W...EXCEPT SW SWELLS ARE MIXED WITH NW SWELLS W OF 120W. THE AREA OF SWELLS WILL GRADUALLY DIMINISH OVER THE NEXT 24-48 HOURS WITH SEAS TO 8 FT IN S TO SW SWELLS S OF A LINE FROM 02N137W TO 01N120W TO 01S108W AT THAT TIME. GAP WINDS... GULF OF PAPAGAYO...PULSING WINDS OF 20-25 KT ARE EXPECTED ACROSS THIS GULF DURING THE LATE NIGHT AND EARLY MORNING HOURS WITH THE ASSISTANCE OF THE NOCTURNAL DRAINAGE FLOW AND SOME ADDED ENHANCEMENT FROM THE EASTERLY GRADIENT FLOW ACROSS THE SW CARIBBEAN. SEAS ARE FORECAST TO BUILD UP TO 11 FT LATE TONIGHT...AND LOWER SLIGHTLY TO 10 FT LATE MON NIGHT. THE RESULTANT ENE SWELLS WILL PROPAGATE WESTWARD REACHING TO NEAR 106W BY LATE MON NIGHT AND TO NEAR 107W EARLY ON TUE. GULF OF TEHUANTEPEC...N WINDS OF 20-25 KT WILL COMMENCE THROUGH THE GULF BEGINNING EARLY ON MON AS A TROPICAL WAVE MOVES ACROSS CENTRAL AMERICA AND THE ISTHMUS OF TEHUANTEPEC. THESE WINDS ARE FORECAST TO DIMINISH TO 15-20 KT BY EARLY MON AFTERNOON...BUT WILL PULSE AGAIN TO 20-25 KT LATE MON NIGHT INTO TUE MORNING. SEAS ARE FORECAST TO BUILD TO AROUND 8 FT BY LATE MON NIGHT AND TO 10 FT BY EARLY ON TUE WITH THESE NLY WINDS. $$ AGUIRRE