From owner-wx-tropl@LISTSERV.ILLINOIS.EDU Mon Dec 13 14:11:10 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 oBD6B94k010104 for ; Mon, 13 Dec 2010 14:11:10 +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 oBCMJFYx027712; Mon, 13 Dec 2010 00:10:58 -0600 (CST) Received: by LISTSERV.ILLINOIS.EDU (LISTSERV-TCP/IP release 14.5) with spool id 4746822 for WX-TROPL@LISTSERV.ILLINOIS.EDU; Mon, 13 Dec 2010 00:10:55 -0600 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 oBD6ArTn014010 for ; Mon, 13 Dec 2010 00:10:53 -0600 (CST) 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 oBD6Alwr018884 for ; Mon, 13 Dec 2010 00:10:53 -0600 (CST) Received: by weather3.admin.niu.edu (Postfix, from userid 501) id 0E2CA3FE0886; Mon, 13 Dec 2010 00:10:46 -0600 (CST) X-Proofpoint-Spam-Reason: safe Message-ID: <20101213061047.0E2CA3FE0886@weather3.admin.niu.edu> Date: Mon, 13 Dec 2010 00:10:46 -0600 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 238 FXPQ60 PGUM 130610 AFDPQ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TIYAN GU 410 PM CHST MON DEC 13 2010 .SYNOPSIS... SURFACE RIDGING AND UPPER-LEVEL CONVERGENCE PREDOMINATE. AN INVERTED SURFACE TROUGH IS PASSING WELL TO THE SOUTH OF GUAM. THE ATTENDANT CONVECTION IS CONFINED TO SOUTH OF 11N...BUT CONVERGENT TRADE-WINDS EAST OF THE TROUGH ARE PRODUCING SOME ISOLATED SHOWERS NORTH OF CHUUK AND POHNPEI BETWEEN 10N AND 14N FROM 150E TO 160E. && .DISCUSSION... NO SIGNIFICANT CHANGES TO FORECAST REASONING. INHERITED FORECAST ALREADY FACTORS IN THE VERY DRY SHORT TERM ENVIRONMENT. SOMEWHAT MOISTER AIR SHOULD BE ARRIVING TOMORROW COURTESY OF THE ZONE OF WEAK TRADE-WIND CONVERGENCE PRESENTLY NORTH OF CHUUK AND POHNPEI. OTHERWISE...NO SIGNIFICANT WEATHER MAKERS ARE FORESEEN THROUGH THE FORECAST PERIOD. && .MARINE... IPAN BUOY COMES IN WITH A MAXIMUM SIGNIFICANT SWELL HEIGHT OF AROUND 5 FEET FROM 070 DEGREES. THIS INITIALIZES WELL WITH THE GRIDDED TRADE-WIND SWELL. RECENT GUAM SURF OBS SUGGEST NORTH SWELL HAVE ALREADY PEAKED BUT WILL RETAIN NORTH SWELL GRIDS DECLINING TO 2 FEET BY TUESDAY MORNING. IN ANY CASE...SURF ON NORTH AND EAST FACING REEFS SHOULD REMAIN AT MODERATE RIP CURRENT RISK LEVELS FOR THE NEXT FEW DAYS. && .EASTERN MICRONESIA... PLEASANT WEATHER REMAINS IN PLACE ACROSS THE REGION. WEAK SURFACE TROUGHS ARE LOCATED NEAR POHNPEI AND JUST EAST OF THE DATELINE. UPPER-LEVEL WINDS HAVE PUSHED CLOUD TOPS SOUTHEASTWARD OVER POHNPEI WHILE SHOWERS IN THE VICINITY OF POHNPEI SLOWLY PUSH WESTWARD. GFS GUIDANCE HOLDS SHOWERS IN PLACE OVER POHNPEI ALMOST INTO WEDNESDAY. ECMWF AND UKMET GUIDANCE WASH OUT THE WESTERNMOST TROUGH WITH SHOWERS TAPERING BY TOMORROW MORNING. AT THIS POINT...FORECAST WILL LEAN TOWARDS A DRIER MORE CLIMATOLOGICAL OUTLOOK. THE TROUGH NEAR THE DATELINE LOOKS UNIMPRESSIVE IN SATELLITE IMAGERY. MODEL GUIDANCE SHOWS LITTLE EVIDENCE FOR ANYTHING MORE THAN ISOLATED SHOWERS THROUGH THE WEEK. && .WESTERN MICRONESIA... CONVECTION ASSOCIATED WITH A FAIRLY IMPRESSIVE SURFACE TROUGH PRESENTLY LOCATED BETWEEN YAP AND CHUUK WILL BEGIN MOVING OVER YAP AND KOROR TONIGHT. SATELLITE IMAGERY SHOWS DEEP CONVECTION EAST OF YAP BUT MODEL ANALYSIS SHOWS UPPER-LEVEL DYNAMICS ARE SPREADING TOWARDS BOTH KOROR AND YAP FROM THE EAST-SOUTHEAST. HAVE ACCORDINGLY ADDED A SLIGHT CHANCE OF THUNDERSTORMS TO THE FORECAST FOR TONIGHT. GFS NEAR TERM GUIDANCE AND SATELLITE TRENDS STILL SUGGEST SCATTERED SHOWERS WILL BECOME ISOLATED OVER BOTH LOCATIONS TUESDAY AFTERNOON. A WEAK SURFACE TROUGH LOCATED NEAR POHNPEI WILL BRING MOSTLY CLOUDY CONDITIONS LATER TONIGHT. DESPITE THE RATHER SMALL AREAL COVERAGE OF SHOWERS WITH THIS SYSTEM AT PRESENT...MODELS KEEP CLOUDS THROUGH MUCH OF THE WEEK AT CHUUK. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...NONE. MARIANAS WATERS...NONE. && $$ MCELROY/M. AYDLETT +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 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.