000 AXPZ20 KNHC 032200 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SAT JAN 03 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2100 UTC. ...SPECIAL FEATURE... GULF OF TEHUANTEPEC STORM WARNING... A STRONG COLD FRONT WILL BE EAST OF THE CHIVELA PASS BY SUN EVENING. A DENSE AND COLD AIRMASS WILL MOVE OVER 26-28 CELSIUS WATERS IN THE GULF OF TEHUANTEPEC. THE LARGE TEMPERATURE DIFFERENCE BETWEEN THE AIR AND SEA WILL ALLOW FOR INCREASED VERTICAL MIXING. WINDS ARE EXPECTED TO RAPIDLY INCREASE TO GALE FORCE BY SUN NIGHT... REACHING STORM FORCE BY MON MORNING. WINDS OF GALE FORCE AND GREATER ARE EXPECTED TO PERSIST FOR SEVERAL DAYS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM 05N77W TO 05N88W. THE ITCZ AXIS EXTENDS FROM 05N88W TO 06N103W TO 07N116W TO 06N140W. SCATTERED MODERATE FROM 03N TO 07N BETWEEN 93W AND 105W...AND FROM 04N TO 11N BETWEEN 105W AND 116W. ...DISCUSSION... A 995 MB LOW PRES SYSTEM NE OF THE HAWAIIAN ISLANDS NEAR 29N151W EXTENDS A COLD FRONT SW TO THE N COAST OF THE BIG ISLAND OF HAWAII. GALE FORCE WINDS LIE AHEAD OF THIS LOW WELL W OF THE FORECAST AREA. THE LOW IS EXPECTED TO INTENSIFY AS IT MOVES N AND OCCLUDES OVER THE NEXT TWO DAYS. A STRONG MID-LEVEL SHORTWAVE WILL MOVE INTO THE EASTERN PORTION OF THE DEEP LAYER TROUGH SUPPORTING THIS FRONT...TURNING THE TROUGH NEGATIVE TILT. WINDS ARE EXCEPTED TO INCREASE TO 30 KT IN NW WATERS ON SUN AND REMAIN JUST BELOW GALE FORCE AS THE FRONT APPROACHES NW WATERS MON. NW SWELL WILL OUTRUN THE FRONT...WITH SEAS INCREASING 16 FT BY MON MORNING. SHOWERS AHEAD OF THE FRONT ARE BEGINNING TO MOVE INTO NW WATERS TODAY...WITH THUNDERSTORMS EXPECTED OVER THE FORECAST AREA LATE SUN THROUGH MON. A SUBTROPICAL RIDGE EXTENDS FROM 1026 MB HIGH PRES N OF THE AREA NEAR 33N129W TO THE SOUTHERN TIP OF THE BAJA CALIFORNIA PENINSULA. THE PRES GRADIENT BETWEEN THE RIDGE AND THE ITCZ IS SUPPORTING A LARGE AREA OF MODERATE TO FRESH TRADE WINDS W OF 115W. THE SUBTROPICAL RIDGE SHOULD SHIFT SLIGHTLY E AS THE COLD FRONT IN THE CENTRAL PACIFIC MAKES ITS WAY EASTWARD. THIS WILL EXPAND THE AREA OF MODERATE TO FRESH TRADES EASTWARD AS WELL AS THE AREA OF 8-10 FT SEAS IN MIXED NW AND EASTERLY SWELL FOUND N OF THE ITCZ. A WEAK LOW-LEVEL TROUGH ANALYZED AT THE SURFACE FROM 12N115W TO 03N117W IS FORECAST TO MOVE W AROUND 20 KT...WITH WINDS NEAR THE TROUGH EXPECTED TO INCREASE TO A FRESH TO STRONG BREEZE LATE SUN AND MON. THE CONVECTION DESCRIBED ALONG THE ITCZ IN THE SECTION ABOVE IS LOCATED IN THE VICINITY OF THIS TROUGH. SCATTERED MODERATE CONVECTION SHOULD CONTINUE NEAR THE TROUGH THROUGH MON. GAP WINDS... GULF OF PAPAGAYO...HIGH PRES OVER THE CENTRAL ATLC EXTENDS A RIDGE SW THROUGH THE YUCATAN CHANNEL THEN S INTO THE GULF OF FONSECA. THE PRES GRADIENT BETWEEN THIS RIDGE AND THE MONSOON TROUGH/ITCZ...ALONG WITH LOCAL OVERNIGHT DRAINAGE EFFECTS... PRODUCES A STRONG NE BREEZE TO THE GULF OF PAPAGAYO IN THE MORNING. WINDS BRIEFLY DIP BELOW THE ADVISORY CRITERIA OF 20-25 KT IN THE AFTERNOON...BUT COME BACK IN EARNEST THEREAFTER. WINDS ARE EXPECTED TO REACH NEAR GALE FORCE IN THE EARLY MORNING HOURS SUN AND MON...WITH SEAS REACHING AS HIGH AS 11 FT. WINDS AND SEAS ASSOCIATED WITH THE GAP WINDS IN PAPAGAYO WILL EXPAND W AND MEET UP WITH THOSE GENERATED FROM THE GULF OF TEHUANTEPEC BY THE END OF THE FORECAST PERIOD MON MORNING. GULF OF CALIFORNIA...HIGH PRES WILL BUILD IN THE GREAT BASIN N OF THE AREA SUN. THE GRADIENT BETWEEN THIS HIGH PRES AND LEE TROUGHING W OF THE SIERRA MADRE OCCIDENTAL WILL INDUCE 20-25 KT N-NW FLOW IN THE GULF OF CALIFORNIA N OF 25N BY SUN EVENING. LOOK FOR SEAS TO BUILD TO 8 FT BY MON MORNING AS THESE WINDS CONTINUE. $$ FORMOSA