000 AXPZ20 KNHC 222205 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC FRI OCT 22 2010 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2100 UTC. ...ITCZ... AXIS ANALYZED FROM 11N86W TO 08N100W TO 10N130W TO 08N140W. SCATTERED MODERATE ISOLATED STRONG WITHIN 120 NM OF AXIS BETWEEN 87W AND 93W. ...DISCUSSION... A DEEP LAYERED UPPER LEVEL TROUGH IS MOVING QUICKLY ACROSS THE THE WESTERN U.S. AND ENTERS THE FAR NE PORTION OF THE AREA THROUGH 32N113W...AND STRETCHES SW TO 21N118W. ANOTHER UPPER LEVEL TROUGH LINGERS FARTHER WEST WITH AXIS FROM 26N130W SW TO 22N140W. THE ASSOCIATED SURFACE COLD FRONT HAS SLOWED EASTWARD PROGRESSION OVER THE LAST 24-36 HOURS AND REMAINS MOVING E AT 10 KT WHILE CONTINUING TO WEAKEN. THE DISSIPATING COLD FRONT ENTERS THE AREA NEAR 32N123W AND EXTENDS TO 25N133W WITH WINDS LESS THAN 20 KT ON EITHER SIDE OF THE FRONT. HOWEVER...NW OF THE FRONT SEAS REMAIN IN THE 9 TO 10 FT RANGE IN NW SWELL WHILE SEAS GREATER THAN 8 FT REMAIN OVER A LARGE AREA IN THE NW QUARTER OF THE DISCUSSION ZONE. AS THE UPPER LEVEL TROUGH CONTINUES RACING EASTWARD LEAVING THE SURFACE FRONT BEHIND BY THIS EVENING...THE BOUNDARY WILL BECOME DIFFUSE BY EARLY SAT BEFORE REACHING N PORTIONS OF THE BAJA. SEAS ARE EXPECTED TO BE UP TO 8 FT IN SUBSIDING NW SWELLS FROM 10N TO 26N BETWEEN 110W AND 125W. S OF THE UPPER LEVEL TROUGH...A VERY PRONOUNCED SUBTROPICAL JET STREAM BRANCH ENTERS THE REGION THROUGH 20N140W...AND EXTENDS E-NE TO 22N120W WHERE IT BEGINS TO ROUND THE BASE OF THE UPPER LEVEL TROUGH OVER THE WESTERN CONUS. JET CORE WINDS ARE IN THE RANGE OF 50-80 KT. A PLUME OF UPPER LEVEL MOISTURE DERIVED FROM THE DEEP CENTRAL TROPICAL PACIFIC IS PRESENT WITHIN 300 NM S OF THE JET STREAM BRANCH AS NOTED ON SATELLITE WATER VAPOR IMAGERY. AN ELONGATED MIDDLE TO UPPER LEVEL RIDGE IS LOCATED S AND SE OF THIS TROUGH BETWEEN 08N AND 22N BETWEEN 90W AND 142W...THAT SEPARATES UPPER LEVEL WESTERLIES FROM UPPER LEVEL EASTERLIES ACROSS THE TROPICS. PRESENTLY...SCATTERED MODERATE CONVECTION FOCUSED WEST OF A SURFACE TROUGH EMBEDDED WITHIN THE ITCZ ALONG 132W IS CONTINUING TO BE ENHANCED BY AMPLE UPPER LEVEL DIVERGENCE W OF 130W...WITHIN THE WESTERN PERIPHERY OF THE RIDGE. THE AFOREMENTIONED UPPER LEVEL TROUGH WILL MOVE INTO THE CENTRAL U.S. OVER THE WEEKEND...WITH THE TRAILING JETSTREAM FORECAST TO ERODE THIS UPPER RIDGE...AND WEAKEN IT AS IT SHIFTS E OF 125W. WITHIN THE LOW LEVELS...A MONSOON TROUGH EXTENDS FROM THE TROPICAL EPAC E OF 90W NE ACROSS CENTRAL AMERICA TO TROPICAL STORM RICHARD...WHICH IS EMBEDDED IN THE NE END OF THIS TROUGH. SW MONSOON FLOW TO NEAR 20 KT WAS OCCURRING ACROSS THE E PACIFIC TO THE S OF THIS TROUGH...WITH ACTIVE CONVECTION IN THE VICINITY OF THE TROUGH E OF 93W INDUCING DIVERGENCE IN THE UPPER LEVEL EASTERLIES. THE SW MONSOON FLOW SHOULD EXPAND W TO 110W BY SUN. ABUNDANT TROPICAL MOISTURE LOCATED S OF THE TROUGH AXIS WILL ADVECT NE ACROSS PORTIONS OF PANAMA...COSTA RICA...AND NICARAGUA DURING THIS TIME LEADING TO VERY ACTIVE CONVECTION AND PERIODS OF VERY HEAVY RAINFALL. ELSEWHERE AT THE SURFACE...A 1022 MB HIGH IS CENTERED WEST OF THE COLD FRONT NEAR 26N136W DRIFTING EASTWARD OVER THE NEXT 24 HOURS ACROSS NORTHERN PORTIONS OF THE AREA. THE PRESSURE GRADIENT TO THE S OF THIS HIGH PRODUCING A SMALL AREA OF FRESH NE TRADES FROM 12N TO 18N W OF 133W...WITH SEAS 10 FT. AS THE FRONT MOVES FARTHER E OVER THE NEXT 24 HOURS...THE HIGH WILL ESTABLISH AN EAST TO WEST RIDGE AXIS ALONG 26N AND ACT TO EXPAND THE FRESH NE TRADES EASTWARD TO 126W...WITH SEAS EXPECTED TO REMAIN IN THE 8 TO 9 FT RANGE. OTHERWISE...MERGING NW AND SOUTHERN HEMISPHERE SW LONG PERIOD SWELL WILL AFFECT THE AREA WATERS AND MAINTAIN SEAS NEAR 7 FT ACROSS THE EQUATORIAL WATERS...IN THE ABSENCE OF 20 KT TRADES. $$ HUFFMAN/LANDSEA