000 AXPZ20 KNHC 062153 TWDEP AXPZ20 KNHC DDHHMM TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC THU FEB 06 2014 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 2145 UTC. ...SPECIAL FEATURE... GULF OF TEHUANTEPEC...NORTHERLY 20-30 KT WINDS ARE SURGING THROUGH AND DOWNSTREAM OF THE GULF OF TEHUANTEPEC. TONIGHTS NOCTURNAL DRAINAGE WILL INCREASE THE NORTHERLY WINDS TO MINIMAL GALE FORCE AROUND MIDNIGHT AND PERSIST THROUGH LATE MORNING ON FRI. THE NORTHERLY FLOW WILL DIMINISH SIGNIFICANTLY ON FRI EVENING THEN INCREASE AGAIN LATE FRI NIGHT TO 20-25 KT WITH THESE CONDITIONS PERSISTING THROUGH LATE SAT MORNING. THE SAT NIGHT DRAINAGE IS EXPECTED TO BE STRONGER SUPPORTING 20-30 KT THROUGH LATE SUN MORNING WITH 20-25 KT EXPECTED SUN EVENING THROUGH LATE MON MORNING. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS SW FROM THE COAST OF COLOMBIA AT 05N77W TO 05N80W...THEN THE TROUGH AXIS TURNS NW TO 07N86W... THEN SW AGAIN TO 05N95W...THEN W TO 05N100W WHERE SCATTEROMETER WINDS INDICATE A TRANSITION TO AN ITCZ WHICH CONTINUES W TO 05N110W TO 07N118W TO BEYOND 07N140W. ISOLATED MODERATE AND STRONG STRONG CONVECTION IS NOTED FROM 03- 09N BETWEEN 84-90W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED ALONG THE MONSOON TROUGH WITHIN 120 NM EITHER SIDE OF A LINE FROM 06N93W TO 06N99W. SIMILAR CONVECTION IS OBSERVED WELL N OF THE ITCZ WITHIN 90 NM EITHER SIDE OF A LINE FROM 11.5N107W TO 11.5N119W. ISOLATED MODERATE CONVECTION IS NOTED WITHIN 60 NM OF THE ITCZ BETWEEN 100-116W. ...DISCUSSION... A SHORTWAVE TROUGH IS PASSING THROUGH THE NE PORTION WITH ITS MEAN AXIS FROM 32N117W TO 21N122W. UPPER MOISTURE IS NOTED N OF 24N E OF THE TROUGH ACROSS THE CENTRAL BAJA CALIFORNIA PENINSULA AND GULF OF MEXICO AND CONTINUING E ACROSS NORTHERN OLD MEXICO. A SHORTWAVE RIDGE IS BUILDING ACROSS THE NW PORTION WITH SIGNIFICANT MOISTURE SPREADING E ACROSS THE RIDGE AXIS...AND NOW SPILLING SE OVER THE DISCUSSION AREA N OF 28N W OF 127W. FURTHER S AN UPPER CYCLONE IS CENTERED NEAR 14N128W AND AN UPPER ANTICYCLONE IS CENTERED NEAR 12N110W. THESE TWO FEATURES COMBINE TO SET UP AN AREA OF UPPER DIFFLUENCE ENHANCING CONVECTION PREVIOUSLY DESCRIBED TO THE N OF THE ITCZ. THE RESULTANT DEBRIS MOISTURE IS ADVECTED NE IN A NARROW TROPICAL PLUME STREAMING E ACROSS CENTRAL OLD MEXICO. THE E PORTION OF THE DISCUSSION AREA IS DOMINATED BY A BROAD UPPER RIDGE ORIGINATING FROM AN UPPER ANTICYCLONE AT 09N78W WITH THE MAIN RIDGE AXIS EXTENDING NE ACROSS THE WESTERN CARIBBEAN AND ACROSS THE W SUBTROPICAL ATLC. THE RIDGE IS ACCOMPANIED BY VERY DRY UPPER AIR...EXCEPT FOR DEBRIS MOISTURE FROM CONVECTION PREVIOUSLY DESCRIBED ALONG THE MONSOON TROUGH. A 1024 MB SURFACE HIGH IS ANALYZED NEAR 28N132W WITH A LOW LEVEL RIDGE EXTENDING SE TO A FAIRLY SHARP CREST DETECTED BY SCATTEROMETER WINDS AT 14N104W. NW-N WINDS AT 15-20 KT ARE OBSERVED N OF 23N E OF THE RIDGE TO THE PACIFIC COAST OF THE BAJA CALIFORNIA PENINSULA...WITH SEAS OF 4-5 FT IN NW SWELL. THE GRADIENT WILL TIGHTEN AGAIN SAT NIGHT INTO SUN WITH NW 20-25 KT WINDS NEAR 29N116W BY LATE SUN. THESE 20-25 KT CONDITIONS WILL SPREAD S ALONG THE PACIFIC COAST OF BAJA ON MON THEN THE GRADIENT RELAXES AGAIN ON TUE. GULF OF CALIFORNIA...LIGHT...MOSTLY NW...WINDS AT 5-10 KT WITH SEAS OF 1-2 FT ARE EXPECTED THROUGH EARLY FRI. THE NW WINDS WILL INCREASE TO 10-15 KT ACROSS THE SOUTHERN GULF LATE FRI...AND FURTHER INCREASE TO 15-20 KT ACROSS THE ENTIRE WATERS S OF 29N ON SAT EVENING...WITH LITTLE CHANGE THROUGH SUN NIGHT AS SEAS BUILD TO 6 FT IN LONG FETCH AREAS NEAR 25N. THE GRADIENT WILL RELAX ON MON INTO TUE THEN INCREASE AGAIN LATE TUE. GULF OF PAPAGAYO...A NE 20-25 KT PULSE IS EXPECTED TONIGHT THROUGH SUNRISE FRI...THEN ONLY A 15-20 KT EVENT LATE FRI NIGHT INTO EARLY SAT. THE LATE NIGHT DRAINAGE FLOW IS EXPECTED TO INCREASE TO 20-25 KT ON SAT NIGHT AND AGAIN ON SUN NIGHT. $$ NELSON