000 AXPZ20 KNHC 081631 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC FRI DEC 08 2006 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1615 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG...8N84W 5N92W 5N100W 5N111W 6N122W 8N130W 7N140W. NUMEROUS STRONG CONVECTION IS WITHIN 60 NM EITHER SIDE OF AXIS BETWEEN 131W-133W...AND ALSO WITHIN 30 NM EITHER SIDE OF AXIS BETWEEN 126W-128W AND W OF 137W. SCATTERED STRONG CONVECTION IS ELSEWHERE FROM 6N-10N BETWEEN 130W-135W...FROM 7N-9N W OF 135W AND ELSEWHERE WITHIN 60 NM OF THE AXIS BETWEEN 126W-129W. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM EITHER SIDE OF THE AXIS BETWEEN 90W-93W. ...DISCUSSION... MID/UPPER LEVEL CYCLONIC CIRCULATION WITH ABOUT 4-5 DEG IN DIAMETER IS MOVING EAST-NORTHEAST 25 KT OVER NORTHWEST MEXICO. A TROUGH EXTENDS SOUTH-SOUTHWEST FROM THE CIRCULATION THROUGH 23N105W TO 17.5N107.5W. SATELLITE WATER VAPOR IMAGERY INDICATES STRONG SUBSIDENCE AND ASSOCIATED DRY AIR ADVECTING EASTWARD NORTH OF 17N EAST OF 120W. ANOTHER MID AND UPPER LEVEL TROUGH MOVING QUICKLY EASTWARD EXTENDS FROM 30N127W SOUTHWESTWARD TO 22N134W AND TO AN UPPER LEVEL CYCLONIC CIRCULATION RETROGRADING WEST-SOUTHWEST WEST OF THE REGION NEAR 16N143W. MID/UPPER LEVEL RIDGING COVERS THE AREA BETWEEN BOTH TROUGHS WITH MEAN RIDGE AXIS EXTENDING FROM A MID/UPPER LEVEL ANTICYCLONIC CIRCULATION NEAR 12N121W NORTH-NORTHEASTWARD THROUGH 17N125W 23N121.5W AND TO A CREST WELL NORTH OF THE REGION TO OVER NEVADA. THE FLOW IS VERY RAPID FROM WEST TO EAST NORTH OF 21N. DIFFLUENT FLOW PATTERN EXISTING BETWEEN THE RIDGE AND THE UPPER LEVEL CYCLONIC CIRCULATION IS ENHANCING ITCZ CONVECTION WEST OF 127W. IN ADDITION...A WEAK SURFACE TROUGH MOVING WESTWARD ABOUT 15 KT IS ALONG 128W FROM 5N-11N AND IS ALSO AIDING ITCZ CONVECTION. ALSO AT THE SURFACE...A COLD FRONT EXTENDS FROM 32N127W TO 27N130W TO 21N140W. NORTHWEST GALE FORCE WINDS IN THE RANGE OF 25-35 KT ARE WITHIN 480 NM WEST OF THE FRONT NORTH OF 28N. THESE GALE WINDS ARE FORECAST TO DIMINISH WITHIN THE NEXT 12 HOURS. MAIN PROBLEM AFFECTING THE REGION WITH RESPECT TO THIS FRONT ARE THE LARGE NW-N SWELLS THAT WILL BE SPREADING THROUGHOUT MUCH OF THE WESTERN AND CENTRAL SECTIONS OVER THE NEXT FEW DAYS AS THE FRONT WEAKENS AND EVENTUALLY DISSIPATES. WAVEWATCH MODEL CONTINUES TO SUGGESTS MAXIMUM HEIGHTS OF UP TO 24 FT MOVING INTO THE NORTHWEST PART OF THE AREA IN THE WAKE OF THE FRONT. A NEW COLD FRONT BRUSHES THE NORTHERN SECTION OF THE REGION FROM FRIDAY EVENING THROUGH SUNDAY BEFORE QUICKLY WEAKENING AS IT MOVES INTO SOUTHERN CALIFORNIA AND NORTHERN BAJA CALIFORNIA. THIS WILL PROVIDE ANOTHER SHOT OF LARGE SWELLS INTO THE AREA THOUGH NOT AS LARGE AS SEEN WITH THE FIRST FRONT. ABUNDANT MID/UPPER LEVEL MOISTURE IN THE FORM OF BROKEN TO SCATTERED HIGH CLOUDS STREAMING EAST-NORTHEAST COVER THE AREA TO THE EAST AND SOUTH OF BOTH TROUGHS SOUTH TO 8N. OVERCAST HIGH LEVEL CLOUDINESS ARE STREAMING EASTWARD OVER NORTHERN MEXICO ...WITH THE EXCEPTION OF THIN HIGH LEVEL CLOUDS FROM 11N-18N EAST OF 113W. SATELLITE WATER VAPOR IMAGERY INDICATES MODERATE TO STRONG SUBSIDENCE AND ASSOCIATED DRY AIR PRESENT TO THE SOUTHEAST OF THESE HIGH CLOUDS WITH VERY LIMITED CONVECTION FOUND IN THIS AREA. GAP WINDS... MINIMAL GALE EVENT WITH NE WINDS IN THE 25-35 KT IS PRESENTLY OCCURRING OVER THE GULF OF TEHUANTEPEC...AND IS EXPECTED TO LAST THROUGH AT LEAST THE NEXT 48 HOURS. SEAS IN THE GULF OF TEHUANTEPEC WILL SLOWLY SUBSIDE AFTER THE EVENTS CEASES. NE WINDS OF 20 KT ACROSS THE GULF OF PAPAGAYO WEST TO 89W ARE EXPECTED TO CONTINUE THROUGH THE NEXT 48 HOURS THEN DIMINISH TO LESS THAN 20 KT. $$ AGUIRRE