000 AXPZ20 KNHC 071509 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC THU JAN 07 2010 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 1400 UTC. ...ITCZ... THE INTERTROPICAL CONVERGENCE ZONE LIES ALONG A LINE FROM 05N77W TO 02N82W TO 08N110W TO 06N130W TO 07N140W. SCATTERED MODERATE CONVECTION CAN BE FOUND WITHIN 75 NM EITHER SIDE OF THE ITCZ AXIS BETWEEN 127W AND 133W. THERE ARE TWO TROUGHS EMBEDDED WITHIN THE ITCZ. THE FIRST LIES FROM 15N110W TO 06N113W AND HAS SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WITHIN 450 NM E OF THE TROUGH AXIS FROM 06N TO 15N. THE SECOND TROUGH CAN BE FOUND FROM 12N118W TO 05N120W WITH SCATTERED MODERATE CONVECTION LYING WITHIN 120 NM E OF THE TROUGH AXIS FROM 07N TO 10N. ...DISCUSSION... THE AMPLIFIED UPPER TROUGH CENTERED ALONG 115W-120W WILL SLOWLY MOVE EASTWARD FRI AND THEN BECOME ABSORBED IN THE LONGWAVE BROAD TROUGH CENTERED OVER THE EASTERN U.S. THE SOUTHWESTERLY JET ON THE LEADING EDGE OF THIS TROUGH WILL IS EXPECTED TO TURN MORE SOUTHERLY AND INTENSIFY TO OVER 100 KT OVER THE NEXT 36 HOURS. THIS WILL INCREASE THE UPPER LEVEL DIFFLUENCE OVER THE POOL OF MOISTURE EVIDENT IN SATELLITE PRECIPITABLE WATER IMAGERY ALONG AND EAST OF A SURFACE TROUGH EMBEDDED IN THE ITCZ FROM 05N110W TO 06N113W. THE CURRENT CONVECTION ASSOCIATED WITH THIS TROUGH IS NOTED IN THE ITCZ SECTION. SHOWERS EXTEND ALONG THE EAST SIDE OF THE DEEP LAYER TROUGH WELL INTO CENTRAL MEXICO. EXPECT THIS ACTIVE CONVECTIVE PATTERN TO CONTINUE OVER THE NEXT 24-36 HOURS...WITH THE AREA OF STRONGEST CONVECTION SHIFTING SLOWLY EASTWARD. THE CHANCE OF CONVECTION WILL DECREASE SAT AS THE UPPER TROUGH AND THE DIFFLUENCE ASSOCIATED WITH THE UPPER JET ON ITS SE SIDE PULL NORTHEASTWARD OUT OF THE FORECAST AREA. THE SURFACE PATTERN OVER N WATERS...A 1020 MB HIGH PRES NEAR 33N126W WITH A RIDGE AXIS EXTENDING SW TO 23N140W...IS EXPECTED TO SHOW LITTLE CHANGE OVER THE NEXT TWO DAYS. THE STUBBORN RIDGE WILL INHIBIT THE EASTWARD PROGRESS OF THE COLD FRONT CURRENTLY JUST NW OF THE AREA. THE FRONT IS EXPECTED TO BE DISSIPATING AS IT MOVES INTO NW WATERS TONIGHT. HOWEVER...NW SWELL FROM THIS SYSTEM HAS ALREADY BROUGHT SIGNIFICANT WAVE HEIGHTS ABOVE 17 FT IN FAR NW WATERS. THIS SWELL WILL CONTINUE TO PROPAGATE SE OVER THE NEXT TWO DAYS AND WILL REMAIN HIGHEST...IN THE 15 FT TO 20 FT RANGE...OVER NW WATERS. TO THE S OF THE RIDGE AXIS...THE 0544 ASCAT PASS SHOWS WINDS IN THE 20 TO 25 KT RANGE BETWEEN THE ITCZ AND 14N OVER W WATERS. THESE TRADE WINDS ARE EXPECTED TO CONTINUE AS THE RIDGE STAYS IN PLACE. GAP WINDS... GULF OF TEHUANTEPEC...N TO NE WINDS OF 25 TO 35 KT ARE EXPECTED TO DIMINISH TO LESS THAN GALE FORCE THIS MORNING AS THE PRES GRADIENT OVER SE MEXICO WEAKENS. HOWEVER...ANOTHER STRONG COLD PUSHES FAR S INTO THE WESTERN GULF OF MEXICO ON FRI FOLLOWED BY STRONG HIGH PRES THAT BUILDS WELL S INTO SE MEXICO ALLOWING FOR THE PRES GRADIENT TO AGAIN TIGHTEN SIGNIFICANTLY ALONG THE SE MEXICAN COAST. GALE FORCE WINDS WILL BEGIN AGAIN BY THE EARLY MORNING HOURS FRI AND STRENGTHEN FRI AFTERNOON WITH WINDS EXPECTED TO REACH STORM FORCE BY SAT MORNING. SEAS WILL BUILD IN EXCESS OF 12 FT AGAIN FRI AFTERNOON. GULF OF PAPAGAYO...MODIFIED COLD AIR BEHIND THE OLD NW CARIBBEAN COLD FRONT ACROSS CENTRAL AMERICA AND INTO THE TROPICAL EPAC HAS BROUGHT WINDS TO 30 KT IN THE GULF OF PAPAGAYO. WINDS APPEAR TO HAVE VEERED MORE NE TO E OVERNIGHT...DECREASING THE WIND SPEEDS IN THE GULF OF FONSECA BELOW 20 KT. EXPECT THIS COOL PLUME TO ERODE SOMEWHAT OVER THE NEXT 24 HR...BUT NE TRADE WINDS IN THE CARIBBEAN WILL CONTINUE TO BLEED THROUGH CENTRAL AMERICA...KEEPING WINDS IN THE 20 TO 25 KT RANGE DOWNWIND OF PAPAGAYO TO NEAR 89W FRI AND SAT. GULF OF PANAMA...NLY FLOW HAS BEEN SPILLING FROM THE CARIBBEAN S ACROSS THE GULF OF PANAMA...WITH AN ASCAT PASS FROM 0218 UTC SHOWING WINDS TO 25 KT. LOOK FOR THIS NLY FLOW TO PERSIST THROUGH THU BEFORE DIMINISHING TO 20 KT FRI AND BELOW 20 KT BY SAT. GULF OF CALIFORNIA...HIGH PRES BEHIND THE COLD FRONT CURRENTLY OVER THE RIO GRANDE VALLEY WILL SLOWLY SPILL SW INTO THE ROCKIES AND GREAT BASIN OVERNIGHT FRI NIGHT. EXPECT THE INCREASED PRES GRADIENT BETWEEN THIS RIDGING AND TROUGHING OVER THE EASTERN GULF OF CALIFORNIA TO YIELD NW TO N WINDS AROUND 20 KT BY EARLY SAT MORNING. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ SCHAUER