000 AXPZ20 KNHC 270336 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC SUN JAN 27 2008 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0315 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 2N78W 5N90W 10N120W 8N130W 8N140W. NO SIGNIFICANT CONVECTION. ...DISCUSSION... W OF 105W... A DEEP-LAYERED CUT-OFF LOW AND ASSOCIATED TROUGH REMAIN LOCATED OFF THE CALIFORNIA COAST WITH A 1000 MB SURFACE LOW CENTERED ABOUT 710 NM WSW OF SAN DIEGO NEAR 30N130W...AND A COLD FRONT SURGING ACROSS THE AREA FROM 30N122W TO 26N121W TO 15N130W. THE UPPER TROUGH IS BECOMING NEGATIVELY TILTED AS THE VIGOROUS 110+ KT UPPER LEVEL JET HAS BECOME ESTABLISHED ON THE SE PERIPHERY OF THE TROUGH. THE JET ALSO APPEARS TO BE SPLITTING WITH ONE BRANCH STREAMING ENE INTO ARIZONA AND NEW MEXICO INTO THE SUBTROPICAL JET STREAM...AND THE OTHER PART RUNNING NORTHWARD INTO NORTHERN CALIFORNIA INTO THE POLAR JET LOCATED ACROSS THE PACIFIC NORTHWEST. A LARGE AREA OF UPPER DIFFLUENCE E OF THE TROUGH AXIS IS PRODUCING WIDESPREAD CLOUDINESS N OF 13N E OF 123W INTO N/CENTRAL MEXICO WITH EMBEDDED SCATTERED SHOWERS AND ISOLATED TSTMS LYING WITHIN A BAND BETWEEN NW MEXICO AND THE FRONT. RADAR IMAGERY FROM YUMA ARIZONA AND SAN DIEGO ALREADY SHOWS A SHIELD OF STEADY RAIN SURGING NWD ACROSS NORTHERN PARTS OF BAJA CALIFORNIA AND THE GULF OF CALIFORNIA TOWARDS THE U.S. BORDER. ADDITIONAL MOISTURE AHEAD OF THE FRONT IS POISED TO REACH OTHER PARTS OF BAJA CALIFORNIA BY SUN MORNING AND HAS THE POTENTIAL TO BRING SCATTERED SHOWERS TO THE PENINSULA THROUGH AT LEAST EARLY TUE. W OF THE FRONT...THE SURFACE LOW HAS DROPPED S ALONG 30N AND IS EXPECTED THE BRUSH THE REGION TONIGHT WITH A 25-35 KT WIND MAXIMUM READY TO SWING THROUGH THE NORTHERN LATITUDES OF THE AREA W OF 120W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE LOCATED WITHIN THE UNSTABLE AIR BEHIND THE FRONT N OF 28N BETWEEN 125W AND 132W. FARTHER S...A 1010 MB LOW IS LOCATED IN THE TROPICS NEAR 13N124W BUT DEFINITELY HAS MORE BAROCLINIC FORCING THAN WOULD BE EXPECTED AT THAT LATITUDE. UPPER LEVEL WINDS ARE PRIMARILY WESTERLY S OF 20N BUT PART OF THE FLOW SPLITS TO THE NE NEAR 125W IN RESPONSE TO THE CUT-OFF TROUGH TO THE N...AND IS RESULTING IN FAVORABLE UPPER DIFFLUENCE OVER THE SURFACE LOW. SCATTERED SHOWERS AND ISOLATED TSTMS ARE LOCATED PRIMARILY TO THE N AND NE OF THE LOW FROM 13N-20N BETWEEN 117W-125W. OTHER ELEVATED ACTIVITY EXTENDS FARTHER NE TOWARDS THE BAJA PENINSULA DUE TO STRONG ISENTROPIC LIFT OF TROPICAL MOISTURE IN THE LOW TO MID LEVELS. E OF 105W... THE UPPER LEVEL PATTERN OVER MUCH OF SE MEXICO AND CENTRAL AMERICA IS DOMINATED BY A WEAK REX BLOCK WITH RIDGING OCCURRING FROM 10N105W NE TO THE YUCATAN PENINSULA AND TROUGHING FROM THE JAMAICA SW ACROSS HONDURAS/EL SALVADOR TO 5N97W. IN ADDITION...A LARGE MID-LEVEL HIGH IS CENTERED NEAR THE N COAST OF THE YUCATAN PENINSULA WITH AXIS ALONG 22N. THIS PATTERN IS PRODUCING MODERATE/STRONG SUBSIDENCE E OF 100W AND SUPPRESSING MOST DEEP CONVECTION. RELATIVELY DRY LOW-LEVEL AIR AND THE MID-LEVEL SUBSIDENCE ALSO PRODUCED TEMPERATURES ACROSS PARTS OF CENTRAL AMERICA...ESPECIALLY NEAR THE PACIFIC COAST...WHICH WERE SEVERAL DEGREES ABOVE NORMAL TODAY. THE HIGHEST TEMPERATURE NOTED WAS 95 F (35 C) FROM THE CITY OF AMAPALA HONDURAS NEAR THE GULF OF FONSECA. CONDITIONS APPEAR SIMILAR TOMORROW WITH A GOOD POSSIBILITY OF CONTINUED WARMER-THAN-NORMAL WEATHER. GAP WINDS CONTINUE THROUGH TEHUANTEPEC...PAPAGAYO...AND PANAMA AND THE RESULTANT NORTHERLY LOW-LEVEL FLOW HAS PUSHED THE ITCZ WELL S TO NEAR 5N. ALTHOUGH WINDS WITHIN THE GULF OF TEHUANTEPEC WILL MAINLY REACH ABOUT 30 KT...THERE IS A POSSIBILITY THAT THEY COULD REACH MINIMAL GALE CRITERIA AT TIMES WITHIN THE NEXT 36 HRS (THROUGH MON MORNING). $$ BERG