000 AXPZ20 KNHC 190932 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC THU FEB 19 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0900 UTC. ...SPECIAL FEATURES... GULF OF TEHUANTEPEC GALE WARNING...STRONG SURFACE HIGH PRESSURE HAS BEEN BUILDING ACROSS THE WESTERN GULF OF MEXICO INTO SOUTHERN MEXICO BEHIND A COLD FRONT THAT ALREADY HAS MOVED THROUGH THE ENTIRE GULF OF MEXICO. THE FRONT NOW CUTS THROUGH EASTERN CUBA...TO THE ISLAS DE LA BAHIA THAT ARE OFF THE COAST OF HONDURAS. THE TIGHT SURFACE PRESSURE GRADIENT AND A PUSH OF DENSE DRY AND COLD AIR THROUGH THE CHIVELA PASS IN SOUTHERN MEXICO ARE RESULTING IN GALE-FORCE WINDS IN THE GULF OF TEHUANTEPEC. MINATITLAN...ON THE NORTHERN END OF THE ISTHMUS OF TEHUANTEPEC...HAS BEEN REPORTING SUSTAINED WINDS OF NEAR 30 KNOTS WITH HIGHER GUSTS...DURING THE LAST 6 HOURS. THE WIND SPEEDS ARE FORECAST TO INCREASE TO 40 KT DURING THE EARLY MORNING HOURS OF TODAY...THURSDAY...WITH THE HELP OF THE NOCTURNAL DRAINAGE FLOW. THE SEA HEIGHTS WILL BUILD DOWNSTREAM OF THE GULF OF TEHUANTEPEC...REACHING AS HIGH AS 15 FEET BY SUNRISE THIS MORNING. THE GALE-FORCE WINDS WILL PERSIST THROUGH EARLY FRI MORNING...AND THEN DIMINISH TO 15 TO 20 KT AS THE HIGH PRESSURE THAT IS TO THE NORTH OF THE AREA WEAKENS AND SHIFTS EASTWARD. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE ITCZ IS ALONG 06N83W TO 03N99W TO 06N111W TO 04N124W TO 07N135W TO 07N140W. CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM 04N TO 05N BETWEEN 87W AND 89W. SCATTERED STRONG FROM 05N TO 06N BETWEEN 82W AND 83W...FROM 05N TO 06N BETWEEN 85W AND 86W...AND FROM 03N TO 04N BETWEEN 90W AND 92W. SCATTERED MODERATE ISOLATED STRONG FROM 06N TO 08N W OF 135W. ...DISCUSSION... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 32N129W TO 28N132W 23N134W...TO A CUT-OFF CYCLONIC CIRCULATION CENTER THAT IS NEAR 17N134W...TO 09N130W AND TO 02N123W. A SURFACE TROUGH REMAINS FROM A DISSIPATED FRONTAL BOUNDARY...ALONG 33N138W TO 30N140W AND TO 23N140W. A SECOND SURFACE TROUGH IS ALONG 18N127W TO 14N131W. CONVECTIVE PRECIPITATION...SCATTERED MODERATE ISOLATED STRONG FROM 05N TO 20N BETWEEN 124W AND 130W...AND FROM 14N TO 23N BETWEEN 130W AND 134W. THE 33N138W 23N140W TROUGH IS FORECAST TO DISSIPATE LATER TODAY. THE SURFACE RIDGE WILL STRENGTHEN...CREATING A TIGHTER PRESSURE GRADIENT BETWEEN THE 33N138W-T0-23N140W TROUGH AND THE 33N130W 15N106W RIDGE... ENHANCING TRADE WIND FLOW SOMEWHAT FROM 10N TO 20N BETWEEN 120W AND 130W. AN AREA OF SEAS TO 9 FEET IS OBSERVED FROM 04N TO 12N BETWEEN 128W AND 134W BASED ON AN ALTIMETER PASS AND MARINE GUIDANCE. THIS IS DUE TO LONG PERIOD SWELL FROM THE NORTHWEST. THIS IS FORECAST TO DECAY TO 8 FEET AS IT PROPAGATES SOUTHEASTWARD...AND SHRINK IN SPATIAL COVERAGE AFFECTING ONLY THE WATERS FROM 10N TO 13N BETWEEN 125W AND 128W BY 48 HOURS. THE UPPER FEATURES WILL WEAKEN GRADUALLY BUT REMAIN GENERALLY IN PLACE DURING THE NEXT 24 TO 48 HOURS. THIS WILL KEEP THE SURFACE TROUGH IN PLACE AS WELL. A SURFACE RIDGE EXTENDS FROM A 1026 MB HIGH PRESSURE CENTER THAT IS NEAR 33N130W...TO 24N120W AND TO 15N106W. GAP WINDS...WINDS ARE FORECAST TO INCREASE TO 20-25 KNOTS IN THE GULF OF PAPAGAYO STARTING AROUND SUNRISE TODAY...AS SURFACE HIGH PRESSURE BUILDS ACROSS THE NORTHWESTERN CARIBBEAN SEA AND NORTHERN SECTIONS OF CENTRAL AMERICA...IN THE WAKE OF THE CURRENT COLD FRONT THAT PASSES THROUGH EASTERN CUBA...TO THE ISLAS DE LA BAHIA THAT ARE OFF THE COAST OF HONDURAS. THE FORECAST ALSO INCLUDES 30 KNOT WINDS AND SEA HEIGHTS BUILDING TO 9 FEET IN THE GULF OF PAPAGAYO ON FRIDAY MORNING. MODERATE TO FRESH NORTHERLY WINDS ARE EXPECTED ALSO ACROSS THE GULF OF PANAMA BY FRIDAY MORNING...AS WINDS FUNNEL INTO THE GULF OF PANAMA FROM THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA. $$ MT