000 AXPZ20 KNHC 201606 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC FRI FEB 20 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1545 UTC. ...SPECIAL FEATURES... GULF OF TEHUANTEPEC GALE WARNING...THE TIGHT PRES GRADIENT OF THE PAST FEW DAYS IS WEAKENING. N TO NE WINDS OF 30-35 KT ACROSS THE GULF WITHIN 45 NM OF LINE FROM 16N95W TO 15N95W ARE FORECAST TO MARKEDLY DIMINISH TO 20-25 KT WITH POSSIBLE GUSTS TO 30 KT BY EARLY THIS AFTERNOON WITH SEAS SUBSIDING FROM 14 FT TO 10 FT. BY EARLY THIS EVENING THESE WINDS ARE FORECAST TO DIMINISH TO 20 KT OR LESS WITH SEAS OF 8 FT IN MIXED NE AND NW SWELL. THIS SEAS WILL BE SLOW IN SUBSIDING AS INDICATED BY WAVEWATCH GUIDANCE BY EARLY SUN...MIXED NE AND SW SWELLS ARE EXPECTED TO RESULT IN 8 FT SEAS OVER AN AREA FROM 04N TO 08N BETWEEN 94W AND 100W. GULF OF PAPAGAYO GALE WARNING...A TIGHT PRES GRADIENT BETWEEN LOWER PRES ASSOCIATED WITH A MONSOON TROUGH SEGMENT THAT EXTENDS FROM JUST TO THE SW COSTA RICA NE TO ITS CENTRAL COAST AND HIGH PRES RIDGING SWD OVR CENTRAL AMERICA IS RESULTING IN NE 20-25 KT WINDS WITHIN 60 NM OF A LINE FROM 10N86W TO 09N89W TO 08N90W...INCLUDING THE GULF OF PAPAGAYO..WITH SEAS TO 8 FT. THESE WINDS ARE FORECAST TO INCREASE TO 20-30 LATE TONIGHT WITH 30-35 KT WINDS WITHIN ABOUT 45 NM OF THE COAST OF THE GULF WITH SEAS OF 8-10 FT. BY EARLY SAT...THE NE WINDS WILL STILL RANGE IN THE 20-30 KT WITH THE 30-35 KT NEAR THE COAST. HOWEVER...BY EARLY SAT EVENING WITH THE WEAKENING OF THE GRADIENT...THE WINDS WILL RESPOND BY DIMINISHING FURTHER TO 20 KT OR LESS WITH SEAS 8 FT IN MIXED NE...SW AND NW SWELL. ON EARLY SUN...A SLIGHT SURGE IN HIGH PRES ALONG WITH OVERNIGHT DRAINAGE FLOW MAY BE SUFFICIENT TO BRING NE 20-25 KT WITHIN 30 NM OF LINE FROM 11N86W TO 10N87W...INCLUDING THE GULF OF PAPAGAYO WITH SEAS TO 8 FT. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH AXIS EXTENDS FROM 09N854 TO LOW PRES AT 05N89W 1010 MB TO 04N92W TO 03N98W. ITCZ EXTENDS FROM 03N98W TO 04N110W TO 05N120W TO 05N130W TO 05N140W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM N OF THE ITCZ BETWEEN 121W-126W. ...DISCUSSION... A CUT-OFF MID TO UPPER LOW LIFTING NE IS SITUATED NEAR 22N130W 18N133W WITH A TROUGH EXTENDING SOUTH TO NEAR 08N133W. THIS CUT- OFF LOW REMAINS AT THE SOUTHERN END OF A LARGE NARROW UPPER TROUGH THAT EXTENDS FROM CENTRAL CALIFORNIA SW TO 32N129W...S TO THE AFOREMENTIONED LOW AND SE TO NEAR 08N123W. A SURFACE TROUGH REFLECTION OF THIS UPPER-LEVEL FEATURE IS ANALYZED FROM 23N132W TO 15N132W. UPPER LEVEL DIVERGENCE TO THE E OF THE LOW IN COMBINATION WITH VERY MOIST AND UNSTABLE ELY FLOW E OF THE LOW AND TROUGH IS INITIATING LARGE CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION FROM 10N TO 18N BETWEEN 122W AND 128W. SCATTERED MODERATE CONVECTION IS WITHIN 60 NM E OF THE TROUGH...AND ALSO WITHIN 30 NM OF 19N131W. THE CUT-OFF LOW IS FORECAST TO MOVE NE OVER THE NEXT 48 HOURS WHILE GRADUALLY WEAKENING. THE SURFACE TROUGH WILL REMAIN NEARLY STATIONARY THROUGH FRI. MODEL GUIDANCE IS SHOWING THAT THE NEXT COLD FRONT TO APPROACH THE NW PORTION OF THE REGION WILL BE AROUND EARLY SAT EVENING. WAVEWATCH GUIDANCE INDICATES THAT SEAS TO 9 FT IN NW SWELLS WILL OCCUR W OF OF A LINE FROM 32N137W TO 23N140W ALSO BY EARLY SAT EVENING. BY EARLY SUN...THE COLD FRONT IS FORECAST TO BE WEAKENING FROM 32N138W TO 26N140W. WINDS OF 2O KT OR LESS ARE FORECAST W OF A LINE FROM 32N133W TO 17N140W AT THAT TIME WITH SEAS OF 8-10 FT IN NW SWELLS. ALSO AT THE SURFACE...A 1029 HIGH CENTER WELL N OF THE AREA EXTENDS A RIDGE SE TO 32N127W AND TO NEAR 20N118W. THE HIGH IS FORECAST TO REMAIN NEARLY STATIONARY DURING THE NEXT 24 HOURS. GAP WINDS... GULF OF PANAMA...FRESH TO STRONG NORTHERLY WINDS ARE EXPECTED ACROSS THE GULF BY LATE TONIGHT AND EARLY FRI MORNING BEFORE DIMINISHING TO 20 KT OR LESS LATER DURING THE MORNING. THESE WINDS WILL MATERIALIZE AGAIN LATE SAT NIGHT AS HIGH OVER THE NW CARIBBEAN AND ALONG EASTERN CENTRAL TIGHTENS THE PRES GRADIENT OVER THE SW CARIBBEAN SEA. GULF OF CALIFORNIA...MODEL OUTPUT SUGGESTS THAT SW WINDS WILL INCREASE TO 20-25 KT OVER THE FAR NORTHERN SECTOR LATE SAT NIGHT INTO SAT AS LOW PRES FORMS OVER THAT PART OF THE GULF. $$ AGUIRRE