000 AXPZ20 KNHC 290323 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC THU MAY 29 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. ...SPECIAL FEATURE... TROPICAL DEPRESSION ONE IS CENTERED AT 10.2N 86.5W AT 0300 UTC AND IS MOVING SLOWLY N AT 3 KT. THE MINIMUM CENTRAL PRESSURE IS ESTIMATED AT 1003 MB. MAXIMUM SUSTAINED WINDS ARE 25 KT WITH GUSTS TO 35 KT MAINLY IN A CONVECTIVE BAND OVER THE E SEMICIRCLE. HOWEVER A LARGE TSTM CLUSTER HAS RECENTLY DEVELOPED NEAR THE CENTER OVER THE NW QUADRANT AND ANOTHER IMPRESSIVE BAND IS DEVELOPING ABOUT 90 NM W OF THE CENTER WITHIN LIGHTNING DATA INDICATING NUMEROUS STRIKES. MAXIMUM SEAS ARE 11 FT. CURRENT GUIDANCE SUGGESTS THE DEPRESSION WILL DRIFT ON A N TRACK WHICH COULD MOVE IT ONSHORE AS SOON AS 24 HOURS OR AS MUCH AS 36 HOURS AS THE TRACK PARALLELS THE NICARAGUAN PAC COAST WHICH IS ORIENTATED NW TO SE. THE OFFICIAL FORECAST IS FOR GRADUAL STRENGTHENING TO A MINIMAL TROPICAL STORM PRIOR TO LANDFALL IN 24 HOURS. THEREAFTER...AN UPPER CYCLONE WELL TO THE W NEAR 14N94W IS SHIFTING SW WITH TIME WHILE A TROPICAL RIDGE BUILDS W ACROSS THE CENTRAL CARIBBEAN. SO ANY REMNANTS OF THIS LOW IS LIKELY TO TRACK NW FOR A COUPLE OF DAYS ACROSS CENTRAL AMERICA. REGARDLESS OF THE WIND STRENGTH THIS SYSTEM WILL BE A MAJOR RAIN MAKER. ...TROPICAL WAVES... A TROPICAL WAVE N OF 06N ALONG 82.5W HAS BEEN MOVING W AT 15 KT THE PAST 24 HOURS. CONVECTION IS ENHANCED OVER THE CARIBBEAN ALONG THE WAVE AXIS AND A SMALL CLUSTER IS DISSIPATING OVER PANAMA. ...ITCZ... INTERTROPICAL CONVERGENCE ZONE AXIS IS ALONG A DIRECT LINE FROM 09N84W TO 00N135W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN 90 NM OF LINE FROM 08N83W TO 05N100W TO 05N119W. ...DISCUSSION... AN UPPER SHORTWAVE TROUGH DOMINATES THE N PORTION OF THE DISCUSSION AREA WITH ITS MEAN AXIS ALONG 32N124W TO 23N127W. A TROPICAL UPPER ANTICYCLONE IS NEAR 16N129W BUT IS LOSING IDENTITY AS A UPPER RIDGE BUILDS WSW FROM A STATIONARY ANTICYCLONE OVER OLD MEXICO NEAR 25N107W. AN UPPER CYCLONE APPEARS TO HAVE CUT OFF FROM THE WESTERN EXTENSION OF AN ATLC TUTT...WITH THE CYCLONE NOW OVER THE PAC NEAR 13N94W AND MOVING SW AND WEAKENING WITH TIME. UPPER DIFFLUENCE IS ENHANCING CONVECTION OVER THE AREA FROM 03N TO 22N BETWEEN 80W AND 95W AND ALONG THE ITCZ BETWEEN 105W AND 123W AND ALSO NEAR 11N102W. THE RESULTANT DEBRIS MOISTURE IS NOW SPREADING NE OVER THE W CARIBBEAN AND ACROSS THE STRAITS OF FLORIDA AS THE UPPER RIDGE BUILDS W. SOME OF THIS DEBRIS MOISTURE CONTINUES TO SPREAD S OF THE EQ BETWEEN 80W AND 100W. ELSEWHERE THE UPPER LEVELS APPEAR VERY DRY AND SUPPRESSING CONVECTION ALONG THE ITCZ BETWEEN 122W AND 163W. AT THE SURFACE A BROAD RIDGE DOMINATES THE AREA N OF THE ITCZ W OF 117W. NW WINDS TO 20 KT ARE ALONG THE NW COAST OF THE BAJA PENINSULA AND ARE EXPECTED TO EXPAND W AND EXPAND S OVER THE NEXT FEW DAYS. THE DEVELOPING SURFACE LOW PRESSURE DESCRIBED ABOVE IS BEGINNING TO DRIVE 15 TO 20 KT N WINDS THROUGH THE GAP OF TEHUANTEPEC. THESE WINDS ARE EXPECTED TO INCREASE TO 20 TO 30 KT LATER TONIGHT WITH GUIDANCE HINTING AT NEAR GALE CONDITIONS...BUT THIS IS DEPENDANT ON THE DURATION OF THE TROPICAL CYCLONE NEAR THE GULF OF PAPAGAYO. $$ NELSON