000 AXPZ20 KNHC 202202 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SAT FEB 20 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 2130 UTC. ...ITCZ... THE AXIS IS CENTERED ALONG 03N78W TO 06N90W TO 05N107W TO 03N117W TO 04N140W. SCATTERED MODERATE CONVECTION WAS NOTED WITHIN 250 NM S OF THE AXIS BETWEEN 93W AND 100W...AND WITHIN 360 NM S OF THE AXIS BETWEEN 105W AND 110W. SCATTERED MODERATE TO STRONG CONVECTION WAS NOTED WITHIN 180 NM N OF THE AXIS BETWEEN 100W AND 106W. ...DISCUSSION... A VERY PROGRESSIVE PATTERN REMAINS JUST N OF THE DISCUSSION AREA WITH RATHER DEEPLY AMPLIFIED UPPER TROUGHS ADVANCING EASTWARD TOWARDS THE U.S. W COAST. A WEAKENING UPPER LEVEL LOW OVER WESTERN ARIZONA NEAR 34N114W CONTINUES TO MOVE E WITH AN UPPER TROUGH EXTENDING FROM THE LOW TO THE SW NEAR 28N115W. A WEAK MID TO UPPER LEVEL RIDGE IS TO THE W OF THE TROUGH WITH ANOTHER TROUGH W OF THERE FROM 32N128W EXTENDING SW AND CROSSING 140W AT 23N. A SURFACE COLD FRONT ASSOCIATED WITH THE FIRST TROUGH EXTENDS FROM 30N114W TO 26N117W TO 22N126W THEN IS DISSIPATING FROM THERE TO 20N140W. N OF 28N AND W OF THE FRONT TO 128W W TO NW WINDS OF 20 TO 25 KT EXIST. ELSEWHERE W OF THE FRONT WINDS ARE LESS THAN 20 KT. LONG PERIOD NW SWELL CONTINUES TO PROPAGATE THROUGH THE N WATERS W OF THE FRONT AVERAGING BETWEEN 10 AND 15 FT. AHEAD OF THE FRONT AN 1802 UTC ASCAT SCATTEROMETER PASS CAPTURED S TO SW WINDS OF 20 KT N OF 28N E OF THE FRONT IN THE GULF OF CALIFORNIA. THE FRONT WILL CONTINUE EASTWARD MOVING INLAND OVER MAINLAND MEXICO WHERE IT WILL WEAKEN DURING THE NEXT 24 HOURS WITH THE NW SWELL GRADUALLY SUBSIDING TO 12 FT. LATEST SATELLITE WATER VAPOR IMAGERY SHOWS MODERATE SUBSIDENCE FROM 25N TO 30N WITH THE EXCEPTION OF PATCHES OF MID TO HIGH LEVEL MOISTURE AHEAD OF THE PREVIOUSLY DISCUSSED TROUGHS. A JET STREAM BRANCH ENTERS THE AREA NEAR 20N140W STRETCHING E TO NE TO 24N120W TO 26N112W AND ACROSS SOUTHERN BAJA CALIFORNIA AND INTO CENTRAL MEXICO. SATELLITE DERIVED WINDS ASSOCIATED WITH THIS JET ARE 70 TO 120 KT. IN ADDITION TO MAINTAINING MAINLY A ZONAL FLOW PATTERN ACROSS JUST ABOUT THE REMAINDER OF THE ENTIRE AREA THIS JET ALSO CONTINUES TO ADVECT PLENTIFUL MID TO UPPER LEVEL MOISTURE FROM THE DEEP CENTRAL TROPICAL PACIFIC NE TO E ACROSS SOUTHERN MEXICO AND CENTRAL AMERICA AND E OF THE AREA INTO THE NW CARIBBEAN SEA. ELSEWHERE A NEARLY STATIONARY UPPER LEVEL ANTICYCLONE WAS NOTED NEAR 06N118W WITH AN UPPER RIDGE AXIS EXTENDING FROM THERE TO 15N118W. BROAD MID TO UPPER LEVEL ANTICYCLONIC FLOW COVERS THE AREA SOUTHWARD FROM THE ABOVE JET STREAM SOUTHWARD AND W OF 100W. A MID TO UPPER LEVEL TROUGH EXTENDS FROM NEAR GUATEMALA TO NEAR 09N105W. UPPER LEVEL DIFFLUENCE NEAR THE SOUTHERN PORTION OF THIS TROUGH CONTINUES TO PROVIDE AMPLE UPPER LEVEL VENTILATION FOR SCATTERED MODERATE TO STRONG CONVECTION WITHIN 180 NM N OF THE ITCZ AXIS BETWEEN 100W AND 106W. UPPER LEVEL DEBRIS MOISTURE FROM THIS CONVECTIVE ACTIVITY IN THE FORM OF SCATTERED MID TO HIGH CLOUDS CONTINUES TO BE ADVECTED NE ACROSS CENTRAL AMERICA. ANOTHER MID TO UPPER TROUGH EXTENDS FROM VENEZUELA SW TO NEAR 05N79W. THIS FEATURE WAS PREVIOUSLY ENHANCING SCATTERED TSTM ACTIVITY ALONG THE COLOMBIAN COAST ALTHOUGH THIS ACTIVITY HAS DISSIPATED DURING THE PAST 6 HOURS. AT THE SURFACE...A 1023 MB HIGH PRES IS ANALYZED NEAR 27N137W WITH A RIDGE EXTENDING TO THE E NEAR 27N126W. THE PRES DIFFERENCE BETWEEN THE HIGH AND LOWER PRES ASSOCIATED WITH THE ITCZ IS ALLOWING FOR AN AREA OF NE TO E 20 TO 25 KT WINDS FROM 09N TO 20N W OF 130W AS INDICATED BY A 1515 UTC WINDSAT SCATTEROMETER PASS AND A 1805 UTC ASCAT SCATTEROMETER PASS. VARIOUS MODEL GUIDANCE AGREES THAT THE HIGH WILL SHIFT E TO SE TO NEAR 26N133W IN 24 HRS. AS A RESULT THE AREA OF TRADES IS EXPECTED TO EXPAND EASTWARD TO NEAR 116W IN 48 HOURS. A 1009 MB LOW IS EMBEDDED IN THE ITCZ NEAR 06.5N108W MOVING W AROUND 10 KT. THE AFOREMENTIONED MID TO UPPER LEVEL TROUGH DIGGING S NEAR THIS SURFACE TROUGH IS ENHANCING CONVECTION AROUND THE LOW WITH NUMEROUS STRONG CONVECTION NOTED WITHIN 120 NM OF LOW CENTER. A 1628 UTC ASCAT SCATTEROMETER PASS CAPTURED WINDS OF 20 TO 30 KT WITHIN 90 NM OF THE LOW CENTER. THIS LOW WILL BECOME CENTERED NEAR 06N112W WHILE WEAKENING SLIGHTLY TO 1010 MB IN 24 HOURS THEN WILL WEAKEN FURTHER WITH WINDS DIMINISHING TO LESS THAN 20 KT IN 48 HOURS. A SURFACE TROUGH IS ALSO EMBEDDED IN THE ITCZ EXTENDING FROM 09N132W TO 01N136W AND IS DRIFTING W. A 1518 UTC WINDSAT SCATTEROMETER PASS SHOWED N TO NE WINDS OF 20 TO 25 KT WITHIN 180 NM W OF THE TROUGH AXIS. THE TROUGH WILL CONTINUE TO DRIFT TO THE W AND WILL EVENTUALLY WEAKEN AND BECOME ILL-DEFINED WITHIN 48 HOURS. GAP WINDS... A 1624 UTC ASCAT SCATTEROMETER PASS AND SEVERAL SHIP OBSERVATIONS REPORTED N WINDS OF 20 KT IN THE GULF OF TEHUANTEPEC. WINDS WILL DIMINISH TO LESS THAN 20 KT AS THEY SHIFT TO THE S IN 6 HOURS OR LESS. 20 KT N WINDS IN THE GULF OF PANAMA WILL DIMINISH TO LESS THAN 20 KT IN THE NEXT 6 HOURS AS N TO NE TRADES N OF THE ISTHMUS OF PANAMA IN THE SW CARIBBEAN WEAKEN. AN EARLIER 1154 UTC WINDSAT PASS CAPTURED NE TO E WINDS OF 20 TO 25 KT IN THE GULF OF PAPAGAYO. THESE WINDS WILL DIMINISH TO LESS THAN 20 KT WITHIN THE NEXT 30 HOURS AS TRADES IN THE SW CARIBBEAN WEAKEN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LEWITSKY