000 AXPZ20 KNHC 061543 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC THU JAN 06 2011 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1500 UTC. ...ITCZ... THE INTERTROPICAL CONVERGENCE ZONE AXIS IS CENTERED FROM LOW PRES 1009 MB NEAR 05N79W TO 08N101W TO 10N122W TO 08N137W TO 07N140W. SCATTERED MODERATE CONVECTION IS FROM 02N TO 07N BETWEEN 81W AND 84W. ...DISCUSSION... A FILLING 1016 MB LOW PRES IS CENTERED NEAR 28N129W REMAINING NEARLY STATIONARY AND IS FORECAST TO DISSIPATE WITHIN THE NEXT 24 HOURS. A RIDGE EXTENDS FROM A 1028 MB HIGH PRESSURE CENTERED N OF THE AREA NEAR 39W127W TO W OF THE AREA NEAR 23N143W. WHILE THE WIND FIELD FROM THIS LOW HAS DIMINISHED BELOW 20 KT...A STRONGER 1001 MB LOW CENTERED W-NW OF THE AREA NEAR 31N150W CONTINUES TO GENERATE SEAS OF 8 TO 12 FT IN NW SWELL OVER MUCH OF THE DISCUSSION AREA N OF 20N W OF 110W. AS A GENERALLY WEAKER PRESSURE GRADIENT EXISTS W OF 110W THROUGH THE PERIOD...TRADE WINDS ARE EXPECTED TO REMAIN BELOW 20 KT...WITH LINGERING NW SWELLS AND SEAS OF 8 TO 10 FT. SURFACE RIDGING WILL BUILD OVER THE EASTERN PART OF THE AREA N OF 20N. THIS WILL TIGHTEN THE PRESSURE GRADIENT W OF BAJA CALIFORNIA...AND INCREASE WINDS TO 20 KT WITHIN 180 NM OF THE BAJA CALIFORNIA COAST BY LATE FRIDAY INTO EARLY SATURDAY. STRONG HIGH PRESSURE OVER THE GREAT BASIN REGION COMBINED WITH LOW PRESSURE OVER SW MEXICO IS CREATING A PRESSURE GRADIENT WHICH IS SUPPORTING NW WINDS OF 20-25 KT OVER THE GULF OF CALIFORNIA. AS THE HIGH PRESSURE OVER THE GREAT BASIN REGION WEAKENS OVER THE NEXT 48 HOURS...THE PRESSURE GRADIENT WILL RELAX AND 20 KT WINDS OVER THE GULF OF CALIFORNIA WILL DECREASE FROM N TO S. A TROUGH EXTENDS FROM 14N120W TO 07N122W. AN EARLIER 06/0512 UTC ASCAT PASS AND SATELLITE IMAGERY INDICATES FRESH TO STRONG NE WINDS AND DISSIPATING CONVECTION AND ASSOCIATED MIDDLE TO UPPER LEVEL MOISTURE ADVECTING NORTHEASTWARD OVER THE AREA FROM 15N TO 25N BETWEEN 107W AND 125W. THE TROUGH IS FORECAST TO GRADUALLY WEAKEN OVER THE NEXT 24 HOURS AND DISSIPATE BY EARLY SATURDAY WITH THE ASSOCIATED WINDS DIMINISHING BELOW 20 KT. A STATIONARY 1009 MB LOW IS OVER THE FAR EASTERN PORTION OF THE AREA CENTERED NEAR 05N78W...WITH SCATTERED MODERATE CONVECTION OCCURRING WITHIN 90 NM OF THE WESTERN SEMICIRCLE. GAP WINDS... A COLD FRONT OVER THE GULF OF MEXICO WILL CONTINUE MOVING EASTWARD PAST THE BAY OF CAMPECHE TODAY WITH DENSER AIR BEHIND THE FRONT EXPECTED TO FUNNEL THROUGH THE CHIVELA PASS INTO THE GULF OF TEHUANTEPEC BY THURSDAY AFTERNOON. N WINDS WILL INCREASE TO 20 KT INITIALLY...THEN INCREASE TO 30 KT LATE TONIGHT INTO EARLY FRIDAY. THERE IS A PROGRESSIVE UPPER LEVEL LEVEL PATTERN WHICH WILL QUICKLY SHIFT THE COLD HIGH PRESSURE IN THE WAKE OF THE FRONT INTO THE CENTRAL GULF OF MEXICO FRIDAY NIGHT. THIS WILL RESULT IN SE RETURN FLOW DEVELOPING OVER THE WESTERN GULF OF MEXICO...AND DIMINISH THE WINDS FUNNELING THROUGH THE CHIVELA PASS. WINDS ARE EXPECTED TO DIMINISH BELOW 20 KT FRIDAY NIGHT... WITH A SMALL AREA OF 8 FT NE SWELL LINGERING SW OF THE GULF OF TEHUANTEPEC AREA. WINDS OVER THE GULF OF PAPAGAYO WILL DIMINISH BELOW 20 KT BY THIS AFTERNOON...HOWEVER WILL BE REINVIGORATED BY THE COLD FRONT CURRENTLY OVER THE GULF OF MEXICO AS IT CONTINUES MOVING SOUTHEASTWARD INTO THE WESTERN CARIBBEAN. WINDS FUNNELING THROUGH THE CENTRAL AMERICA PASSES WILL ONCE AGAIN INCREASE... WITH WINDS INCREASING TO 20 KT OVER THE GULF OF PAPAGAYO LATE FRIDAY INTO EARLY SATURDAY. $$ HUFFMAN