From owner-wx-tropl@LISTSERV.ILLINOIS.EDU Sun Oct 24 05:55:23 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 o9NLtMY4005861 for ; Sun, 24 Oct 2010 05:55:23 +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 o9N518QI021767; Sat, 23 Oct 2010 16:55:08 -0500 (CDT) Received: by LISTSERV.ILLINOIS.EDU (LISTSERV-TCP/IP release 14.5) with spool id 4013588 for WX-TROPL@LISTSERV.ILLINOIS.EDU; Sat, 23 Oct 2010 16:55:08 -0500 Received: from relay08.cites.uiuc.edu (relay08.cites.uiuc.edu [128.174.196.9]) by vacuum.cso.uiuc.edu (8.14.2/8.14.2) with ESMTP id o9NLt8Th001753 for ; Sat, 23 Oct 2010 16:55:08 -0500 (CDT) Received: from weather3.admin.niu.edu (weather3.admin.niu.edu [131.156.8.48]) by relay08.cites.uiuc.edu (8.14.4/8.14.2) with ESMTP id o9NLt16q028183 for ; Sat, 23 Oct 2010 16:55:07 -0500 (CDT) Received: by weather3.admin.niu.edu (Postfix, from userid 501) id 8E8DA108B0001; Sat, 23 Oct 2010 16:54:59 -0500 (CDT) X-Proofpoint-Spam-Reason: safe Message-ID: <20101023215500.8E8DA108B0001@weather3.admin.niu.edu> Date: Sat, 23 Oct 2010 16:54:59 -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 976 FXPQ60 PGUM 232154 AFDPQ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TIYAN GU 754 AM CHST SUN OCT 24 2010 .SYNOPSIS... RECENT WATER VAPOR SATELLITE IMAGERY SHOWS A NEARLY STATIONARY TUTT CELL CENTERED EAST OF SAIPAN NEAR 15N149E. A LOBE OF VORTICITY APPEARS TO HAVE SHARPENED UP A BIT ON THE NORTH SIDE OF THE TUTT. THIS HAS LED TO THE FORMATION OF MAINLY STRATIFORM CONVECTION IN THE CNMI NEAR AND NORTH OF TINIAN AND SAIPAN. 88D SCAN SHOWS MAINLY VIRGA FALLING FROM THE CLOUDS OVER SAIPAN AND TINIAN. IF THE RAIN AND CLOUDS PERSIST...A FORECAST UPDATE WILL PROBABLY BE NECESSARY. OTHERWISE...SURFACE RIDGING REMAINS IN CONTROL OF THE WEATHER. VAD WIND PROFILE AND PWAT OF 2.09 FROM THE 12Z SOUNDING SUGGEST ISOLATED PM THUNDER FOR THE MARINE ZONES WEST OF GUAM TODAY. && .DISCUSSION... ONLY MINOR CHANGES TO FORECAST GRIDS NEEDED BEYOND THE FIRST PERIOD. MODEL GUIDANCE KEEPS RELATIVELY DRY PATTERN IN PLACE THROUGH THE FORECAST PERIOD AS WINDS GRADUALLY BACK FROM EAST- SOUTHEAST TO EAST-NORTHEAST WITH TIME. RIDGE BUILDING NORTH OF THE MARIANAS WILL TIGHTEN THE PRESSURE GRADIENT AND CAUSE A MODEST INCREASE IN WIND SPEEDS DURING THE SECOND HALF OF THE WEEK. SURF ON NORTH AND EAST FACING REEFS SHOULD BUILD ABOVE THE MODERATE RIP CURRENT RISK THRESHOLD BY MID WEEK. && .EASTERN MICRONESIA... SHOWERS ASSOCIATED WITH TRADE-WIND CONVERGENCE ARE EXPECTED TO REMAIN NORTH OF THE MARSHALLS THROUGH AT LEAST MONDAY. SATELLITE IMAGERY SHOWS DEVELOPING CONVECTION ALONG A SURFACE TROUGH APPROACHING THE DATE LINE. MODELS HANDLE THIS FEATURE WELL AS FAR AS PLACEMENT SO OPTED FOR SCATTERED SHOWER COVERAGE FOR MAJURO BEGINNING LATE MONDAY OR MONDAY NIGHT. HOWEVER...TIMING OF THIS FEATURE IS STILL QUESTIONABLE AND MAY OUTPACE WHAT MODELS ARE CURRENTLY SHOWING. RELATIVELY DRY CONDITIONS SHOULD PREVAIL OVER KOSRAE AND POHNPEI THROUGH MONDAY. MODEL GUIDANCE SUGGEST THE AFOREMENTIONED TROUGH WILL ATTENUATE BEFORE IT REACHES KOSRAE OR POHNPEI. && .WESTERN MICRONESIA... MODELS SHOW SURFACE TROUGH NEARING CHUUK MAY PROVIDE A ROUND OF SHOWERS TODAY BUT IT APPEARS MOST OF THE CONVECTION HAS ALREADY PASSED TO THE WEST. ACCORDINGLY...ONLY ISOLATED SHOWER COVERAGE IS EXPECTED. MODELS HAVE BACKED OFF ON SHOWER COVERAGE FOR YAP...KEEPING MOST OF THE ACTIVITY TO THE NORTH OF YAP TODAY. THIS WILL BE WHERE LOW-LEVEL CONVERGENCE TO THE SOUTHEAST OF 16W IS STRONGEST. HOWEVER...AN AREA OF CONVECTION CURRENTLY A COUPLE HUNDRED MILES TO THE SOUTHEAST OF YAP MAY STILL PROVIDE SCATTERED SHOWERS THERE LATER TODAY AND TONIGHT. KOROR SHOULD SEE MOSTLY DRY CONDITIONS THROUGH THE FORECAST PERIOD AS A RIDGE AXIS BUILDS OVER THE AREA. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...NONE. MARIANAS WATERS...NONE. && $$ MCELROY/WILLIAMS +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 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.