000 AXPZ20 KNHC 150330 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC TUE JAN 15 2013 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 0300 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH IS ALONG 04N77W TO 07N87W TO 06N98W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 06N98W TO 10N120W TO 10N127W THEN RESUMES FROM 07N132W TO 05N140W. SCATTERED MODERATE CONVECTION IS WITHIN AN AREA BOUNDED BY 06N133W TO 12N133W TO 19N120W TO 06N123W TO 06N133W. ...DISCUSSION... STRONG 1039 MB HIGH PRES IS CENTERED WELL N OF THE DISCUSSION WATERS NEAR 46N134W WITH A RIDGE EXTENDING SE THROUGH 32N134W TO NEAR 15N103W. THE PRES GRADIENT BETWEEN THIS RIDGE AND LOWER PRES IN THE VICINITY OF THE ITCZ CONTINUES TO MAINTAIN FRESH TO STRONG TRADES GENERALLY FROM 07N TO 23N W OF 113W-120W AS DEPICTED BY EARLIER SCATTEROMETER DATA. THE AREA OF HIGH PRES WILL CONTINUE TO DRIFT TO THE NE WHILE GRADUALLY WEAKENING OVER THE NEXT COUPLE OF DAYS. THIS WILL SLACKEN THE PRES GRADIENT AND DECREASE THE AREAL COVERAGE OF THE STRONG TRADEWIND FLOW OVER THE W CENTRAL WATERS SIGNIFICANTLY BY MIDWEEK. A WEAK SURFACE TROUGH IS EMBEDDED IN THE ITCZ FROM 04N132W TO 10N128. ASSOCIATED CONVECTION IS AS IS DESCRIBED IN THE SECTION ABOVE. THIS TROUGH WILL MOVE WESTWARD WHILE WEAKENING THE NEXT COUPLE OF DAYS. THIS FEATURE IS HELPING TO MAINTAIN THE STRONG TRADES CURRENTLY...BUT ITS WEAKENING WILL ALSO BE A FACTOR IN THE DIMINISHING TRADES BY MIDWEEK. GULF OF CALIFORNIA...VERY STRONG HIGH PRES WILL CONTINUE TO BUILD ACROSS THE U.S. GREAT BASIN REGION. THIS COMBINED WITH WELL DEFINED SURFACE TROUGHING OVER WESTERN MEXICO HAS RESULTED IN FRESH TO NEAR GALE FORCE NW WINDS DOWN THE ENTIRE LENGTH OF THE GULF OF CALIFORNIA THIS EVENING. THESE CONDITIONS WILL PERSIST FOR THE NEXT COUPLE OF DAYS HELPING TO BUILD SEAS UP TO 11 FT IN THE SOUTHERN GULF BY TUE AFTERNOON. GUIDANCE DEVELOPED AROUND A LOCAL RESEARCH STUDY CONTINUES TO INDICATE AROUND A 25 PERCENT PROBABILITY OF GALE CONDITIONS IN THE GULF WITH THE HIGHEST CHANCES DURING TUE NIGHT INTO EARLY WED. WINDS IN THE FORECAST WILL REMAIN CAPPED AT 30 KT UNLESS PROBABILITIES FOR 34 KT WINDS INCREASE A BIT HIGHER. GAP WINDS...WINDS WILL PULSE TO FRESH TO STRONG LEVELS LATER TONIGHT THROUGH EARLY TUE AS TRADES E OF THE AREA IN THE WESTERN CARIBBEAN SEA SPREAD WESTWARD OVERNIGHT...ALSO AIDED BY THE ADDED COMPONENT OF NOCTURNAL DRAINAGE FLOW. WINDS ARE THEN FORECAST TO DIMINISH TO MODERATE TO FRESH LEVELS BY TOMORROW NIGHT. MODERATE TO FRESH NORTHERLY WINDS WILL SEEP INTO THE GULF OF PANAMA FROM THE SW CARIBBEAN THROUGH THE NEXT 12 HOURS OR SO. THE WINDS MAY BRIEFLY AND LOCALLY INCREASE TO STRONG LEVELS OVERNIGHT TONIGHT. WINDS WILL DIMINISH EARLY TUE AFTERNOON THROUGH WED AS WINDS NORTH OF THE AREA WEAKEN. A SURGE OF COLD AIR IS FORECAST TO ARRIVE BEHIND A COLD FRONT IN THE GULF OF MEXICO WED INTO THU. THE PRES GRADIENT WILL TIGHTEN WED AFTERNOON ALLOWING FOR NORTHERLY WINDS TO INCREASE TO FRESH TO STRONG AHEAD OF THE ARRIVAL OF THE FRONT. ONCE THE FRONT CLEARS THE SW GULF OF MEXICO...NORTHERLY WINDS WILL RAPIDLY BE FUNNELED THROUGH THE CHIVELA PASS ACROSS THE GULF OF TEHUANTEPEC AREA...WITH A GALE WARNING NOW IN EFFECT BEGINNING AT 00 UTC THU. MODEL GUIDANCE EVEN HINTS AT THE POTENTIAL FOR MINIMAL STORM FORCE WINDS VERY QUICKLY AFTER GALE FORCE WINDS COMMENCE SO THE GALE WARNING MAY NEED TO BE UPGRADED TO A STORM WARNING IF CURRENT TRENDS CONTINUE. $$ LEWITSKY