From owner-wx-tropl@LISTSERV.ILLINOIS.EDU Mon Oct 4 16:20:27 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 o948KPU7017873 for ; Mon, 4 Oct 2010 16:20:26 +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 o941e5nn025335; Mon, 4 Oct 2010 03:19:31 -0500 (CDT) Received: by LISTSERV.ILLINOIS.EDU (LISTSERV-TCP/IP release 14.5) with spool id 3725116 for WX-TROPL@LISTSERV.ILLINOIS.EDU; Mon, 4 Oct 2010 03:19:31 -0500 Received: from relay03.cites.uiuc.edu (relay03.cites.uiuc.edu [128.174.4.69]) by vacuum.cso.uiuc.edu (8.14.2/8.14.2) with ESMTP id o948JUPJ000042 for ; Mon, 4 Oct 2010 03:19:30 -0500 (CDT) Received: from weather3.admin.niu.edu (weather3.admin.niu.edu [131.156.8.48]) by relay03.cites.uiuc.edu (8.14.4/8.14.2) with ESMTP id o948JObE017919 for ; Mon, 4 Oct 2010 03:19:30 -0500 (CDT) Received: by weather3.admin.niu.edu (Postfix, from userid 501) id 3FA87405016C; Mon, 4 Oct 2010 03:19:24 -0500 (CDT) X-Proofpoint-Spam-Reason: safe Message-ID: <20101004081924.3FA87405016C@weather3.admin.niu.edu> Date: Mon, 4 Oct 2010 03:19:24 -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 071 FXPQ60 PGUM 040819 AFDPQ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TIYAN GU 619 PM CHST MON OCT 4 2010 .SYNOPSIS...SATELLITE SHOWS A TROUGH OF LOW PRESSURE TO THE SOUTHEAST OF GUAM THIS AFTERNOON. THIS TROUGH WILL MOVE WEST AND WILL BRING CLOUDS AND ISOLATED SHOWERS WITH A SLIGHT CHANCE OF THUNDERSTORMS TONIGHT AND TUESDAY. && .DISCUSSION... SATELLITE AND SCATTEROMETER DATA BOTH SHOW A TROUGH OF LOW PRESSURE APPROACHING THE MARIANAS FROM THE EAST. MODELS SHOW THIS TROUGH PASSING ACROSS THE LOCAL AREA OVER THE NEXT 24 HOURS. AT FIRST IT LOOKED LIKE CLOUDS AND POSSIBLE SCATTERED SHOWERS WOULD OVERSPREAD THE ISLANDS AFTER SUNSET. DURING THE AFTERNOON MANY HOLES DEVELOPED IN THE RAIN AREA TO THE SOUTHEAST OF GUAM SO DELAYED THE ONSET OF MOSTLY CLOUDY UNTIL LATER TONIGHT. WAS DEBATING ABOUT SCATTERED SHOWERS...HARD TO PINPOINT ANY TIME THAT SCATTERED SHOWERS MAY OCCUR SO LEFT COVERAGE AS ISOLATED. WITH MANY CBS ASSOCIATED WITH THIS TROUGH ADDED A SLIGHT CHANCE OF THUNDERSTORMS TONIGHT AND TUESDAY. EARLIER FORECAST CONTINUED THE SLIGHT CHANCE OF THUNDERSTORMS THROUGH FRIDAY. WHILE THE ODDS ARE LOW FOR THUNDER TIME HEIGHT DEPICTS ENOUGH MOISTURE AND SO OPTED TO KEEP THEM IN FOR NOW. && .MARINE... AN EAST TRADE-WIND SWELL WILL PERSIST THROUGH THE WEEK. BUOY SHOWS SEA HEIGHT INCREASING TO OVER FOUR FEET THIS AFTERNOON. WW3 SHOWS A FIVE FOOT SWELL ON TUESDAY AND THIS SEEMS LIKELY. THIS WILL BUMP SURF ON EAST FACING REEFS TO 5 TO 7 FEET WHICH IS MODERATE. && .EASTERN MICRONESIA... A DIFFUSE ITCZ STRETCHES EASTWARD ALONG 6N FROM JUST EAST OF CHUUK TO THE DATE LINE...THEN CONTINUES EAST-NORTHEASTWARD THRU 9N165W. PERIODS OF PASSING SHOWERS ARE EXPECTED FOR ALL THE MAJOR LOCATIONS THRU TUESDAY. THEN THE SW TO NE ORIENTATION OF THE ITCZ EAST OF THE DATE LINE WILL ALLOW THE CONVERGENT ZONE TO SHIFT NORTH OF MAJURO ON WEDNESDAY AND PROMOTE FAIRER WEATHER. LATEST ASCAT SATELLITE DATA REVEAL A NORTHEASTERLY TRADE SURGE NEAR THE HAWAIIAN ISLANDS. AS THIS FEATURE CROSSES THE DATE LINE AROUND MIDWEEK...IT WILL ENHANCE CONVERGENCE ALONG THE ITCZ. THIS WILL CAUSE STRONGER AND MORE CONCENTRATED CONVECTION TO FORM ALONG 6N...RESULTING IN WIDESPREAD SHOWERS FOR BOTH POHNPEI AND CHUUK. ON THE OTHER HAND...KOSRAE SHOULD REMAIN RELATIVELY DRY SOUTH OF THE MAIN CONVERGENCE ZONE. AFTER MIDWEEK...FAIRER WEATHER ALREADY OVER MAJURO WILL MOVE WESTWARD AND PROVIDE A BRIEF PERIOD OF PARTLY CLOUDY SKIES. HOWEVER THE RETURN OF EASTERLY TRADES MIGHT INCREASE THE CHANCE FOR TRADE-WIND SHOWERS FOR THE ENTIRE AREA BY THE WEEKEND. && .WESTERN MICRONESIA... A SURFACE TROUGH CURRENTLY BETWEEN GUAM AND CHUUK IS SHOWING SIGNS OF SPLITTING UP. THE WEAKER NORTHERN BRANCH IS MOVING TOWARD THE MARIANAS...WHILE THE MORE ACTIVE SOUTHERN BRANCH IS APPROACHING YAP THIS EVENING. CLOUDS ARE ANTICIPATED TO THICKEN THIS EVENING AND SHOWERS WILL ARRIVE OVER YAP AFTER MIDNIGHT. SIMILAR CONDITIONS WILL ALSO SPREAD INTO KOROR ON TUESDAY BUT FUTURE SHIFTS SHOULD HAVE BETTER TIMING ON THE ONSET OF SHOWERS. THERE SHOULD BE A DECREASE IN SHOWERS AFTER THE PASSAGE OF THE TROUGH DURING MIDWEEK BUT MIGHT PICK UP AGAIN TOWARD THE WEEKEND AS THE LEADING EDGE OF THE ITCZ EXTENDS WESTWARD FROM EASTERN MICRONESIA. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...NONE. MARIANAS WATERS...NONE. && $$ ZIOBRO/CHAN +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 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.