From owner-wx-tropl@LISTSERV.ILLINOIS.EDU Wed Sep 29 16:04:27 2010 Received: from vacuum.cso.uiuc.edu (vacuum.cso.uiuc.edu [128.174.5.113]) by cozumel.ust.hk (8.13.8/8.13.8) with ESMTP id o8T84Q2v022934 for ; Wed, 29 Sep 2010 16:04:26 +0800 Received: from vacuum.cso.uiuc.edu (vacuum.cso.uiuc.edu [128.174.5.113]) by vacuum.cso.uiuc.edu (8.14.2/8.14.2) with ESMTP id o8SJFqRB025335; Wed, 29 Sep 2010 03:03:55 -0500 (CDT) Received: by LISTSERV.ILLINOIS.EDU (LISTSERV-TCP/IP release 14.5) with spool id 3650217 for WX-TROPL@LISTSERV.ILLINOIS.EDU; Wed, 29 Sep 2010 03:03:54 -0500 Received: from relay06.cites.uiuc.edu (relay06.cites.uiuc.edu [128.174.196.8]) by vacuum.cso.uiuc.edu (8.14.2/8.14.2) with ESMTP id o8T83sBZ009339 for ; Wed, 29 Sep 2010 03:03:54 -0500 (CDT) Received: from weather3.admin.niu.edu (weather3.admin.niu.edu [131.156.8.48]) by relay06.cites.uiuc.edu (8.14.4/8.14.2) with ESMTP id o8T83mw1018853 for ; Wed, 29 Sep 2010 03:03:54 -0500 (CDT) Received: by weather3.admin.niu.edu (Postfix, from userid 501) id 1D0A34050030; Wed, 29 Sep 2010 03:03:48 -0500 (CDT) X-Proofpoint-Spam-Reason: safe Message-ID: <20100929080348.1D0A34050030@weather3.admin.niu.edu> Date: Wed, 29 Sep 2010 03:03:48 -0500 Reply-To: wxmaster@COX.NET Sender: WX-TROPL Tropical Storm and Hurricane WX products From: LDM Weather Subject: Western Pacific: Synoptic Discussion For The Marianas To: WX-TROPL@LISTSERV.ILLINOIS.EDU Precedence: list 144 FXPQ60 PGUM 290803 AAA AFDPQ AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE TIYAN GU 600 PM CHST WED SEP 29 2010 .SYNOPSIS... SHOWERS ARE PLENTIFUL ALL AROUND THE MARIANAS AS A TROUGH APPROACHES FROM THE EAST...BUT THE MARIANAS WATERS HAVE BEEN IN A RELATIVE DRY SLOT MOST OF THE AFTERNOON. LOW-LEVEL VORTICITY ASSOCIATED WITH THE TROUGH IS EVIDENT ON RADAR EAST AND SOUTHEAST OF GUAM...AND THE LEADING EDGE OF THE MASS OF SHOWERS TO THE EAST IS MAKING SLOW BUT STEADY PROGRESS TO THE WEST AND NORTHWEST. && .DISCUSSION... LATEST GFS/UKMET AND RADAR/SATELLITE TRENDS AGREE ON THE TROUGH MOVING WEST OVERNIGHT AND THURSDAY...ACCOMPANIED BY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS. SHOWERS SHOULD TAPER OFF LATE IN THE DAY THURSDAY...BUT LINGERING MOISTURE SHOULD KEEP ISOLATED SHOWERS/THUNDER GOING THURSDAY NIGHT. ONCE THE TRADE DISTURBANCE MOVES OFF WESTWARD...GFS INDICATES SIGNIFICANT DRYING IN THE MID AND UPPER LEVELS FOR FRIDAY AND THE WEEKEND AS WEAK SURFACE RIDGING DEVELOPS OVER THE REGION. A DEEP LAYER OF LIGHT AND VARIABLE WINDS WOULD NORMALLY SUGGEST A CHANCE OF ISLAND SHOWERS SAT/SUN...BUT LACK OF MOISTURE WILL LIKELY KILL THAT POSSIBILITY. && .MARINE... NORTH SWELL IS DEFINITELY ON THE WAY OUT...AND SHOULD SEE STEADILY DECLINING SEAS AND SURF THROUGH SATURDAY. && .EASTERN MICRONESIA... FAIR WEATHER IS EXPECTED TO CONTINUE OVER POHNPEI THRU TONIGHT AS DRY GENTLE TRADE WINDS DOMINATE THE AREA. SATELLITE IMAGERY INDICATES THE LOW-LEVEL TROUGH OVER THE MARSHALL ISLANDS IS SOUTH OF MAJURO. ITS LEADING EDGE HAS MOVED WEST OF KOSRAE BUT HAS THINNED OUT ON SATELLITE. WEAKER CONVERGENCE SOUTHEAST OF THE TROUGH AXIS WILL MAINLY CREATE SOME CLOUDS AND A FEW SHOWERS FOR MAJURO INTO THURSDAY. AS THE TROUGH KEEPS SLIDING WESTWARD...IT WILL ALSO INCREASE THE CHANCE FOR SOME SHOWERS TO POHNPEI ON THURSDAY AND CHUUK BY FRIDAY NIGHT. AFTERWARD...WEAKER TRADES BEHIND THE TROUGH ARE GOING TO PROMOTE ANOTHER ROUND OF DRY CONDITIONS FOR MAJURO AND KOSRAE TOWARD THE WEEKEND...AND FOR POHNPEI AND CHUUK OVER THE WEEKEND. HOWEVER... INCREASING TRADE CONVERGENCE FROM THE EAST MIGHT START A WETTING TREND FOR THE MARSHALLS EARLY NEXT WEEK. && .WESTERN MICRONESIA... THE WEAK SURFACE CIRCULATION...ITS ASSOCIATED TROUGH AND THE ASSOCIATED CONVECTION IS NORTHWEST OF KOROR THIS EVENING. WEAK CONVERGING WINDS SOUTH OF THIS FEATURE CAN TAKE ADVANTAGE OF UPPER-LEVEL DIVERGENCE TO SPARK ISOLATED THUNDERSTORMS THRU THIS EVENING. THE NEXT POTENTIAL WEATHER MAKER FOR WESTERN MICRONESIA WILL BE ANOTHER SURFACE TROUGH PASSING SOUTH OF...AND OVER GUAM THIS EVENING. AS IT CLOSES INTO YAP ON THURSDAY...CONVECTIVE ACTIVITY MAY FIRE UP AT YAP. THE BULK OF THE ACTION MIGHT STAY JUST NORTH OF KOROR. IN THE WAKE OF THE PASSAGE OF THIS SECOND TROUGH...FAIR WEATHER CURRENTLY OVER EASTERN MICRONESIA SHOULD FINALLY ARRIVE OVER THE WEEKEND. FAIR WEATHER IS EXPECTED TO CONTINUE OVER CHUUK INTO FRIDAY AS DRY GENTLE TRADE WINDS DOMINATE THE AREA. THE TROUGH RUNNING FROM EASTERN MICRONESIA WILL INCREASE THE CHANCE FOR SHOWERS AT CHUUK LATE FRIDAY AND FRIDAY NIGHT. THE WEAKER TRADES BEHIND THE TROUGH SHOULD PROMOTE FAIR TO MOSTLY CLOUDY WEATHER FOR CHUUK ON SATURDAY. SURF OF AROUND 6 FT ALONG NORTH FACING SHORES WILL GRADUALLY SUBSIDE TO BETWEEN 4 AND 5 FEET BY FRIDAY. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...NONE. MARIANAS WATERS...NONE. && $$ MIDDLEBROOKE/DEVITA +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ To unsubscribe from WX-TROPL send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with "unsub wx-tropl" in the body of your message. For help with WX-TROPL write to cnovy@cox.net. For more information on tropical weather products, see the NHC Homepage at http://www.nhc.noaa.gov.