From owner-wx-tropl@LISTSERV.ILLINOIS.EDU Sat Dec 18 16:50:37 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 oBI8oa0B006692 for ; Sat, 18 Dec 2010 16:50:37 +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 oBI60DKB027712; Sat, 18 Dec 2010 02:50:20 -0600 (CST) Received: by LISTSERV.ILLINOIS.EDU (LISTSERV-TCP/IP release 14.5) with spool id 4812770 for WX-TROPL@LISTSERV.ILLINOIS.EDU; Sat, 18 Dec 2010 02:50:20 -0600 Received: from relay09.cites.uiuc.edu (relay09.cites.uiuc.edu [128.174.4.86]) by vacuum.cso.uiuc.edu (8.14.2/8.14.2) with ESMTP id oBI8oKpc003515 for ; Sat, 18 Dec 2010 02:50:20 -0600 (CST) Received: from weather3.admin.niu.edu (weather3.admin.niu.edu [131.156.8.48]) by relay09.cites.uiuc.edu (8.14.4/8.14.2) with ESMTP id oBI8oD16018920 for ; Sat, 18 Dec 2010 02:50:20 -0600 (CST) Received: by weather3.admin.niu.edu (Postfix, from userid 501) id AF0DA144B0001; Sat, 18 Dec 2010 02:50:13 -0600 (CST) X-Proofpoint-Spam-Reason: safe Message-ID: <20101218085013.AF0DA144B0001@weather3.admin.niu.edu> Date: Sat, 18 Dec 2010 02:50:13 -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 322 FXPQ60 PGUM 180849 AFDPQ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TIYAN GU 649 PM CHST SAT DEC 18 2010 .SYNOPSIS... A NEUTRAL ZONE SOUTHEAST OF A COLD FRONT AND A SHEAR LINE IS PROVIDING GENTLE WINDS AND FAIR WEATHER ACROSS THE MARIANAS. THE LEADING EDGE OF THE SHEAR LINE HAS REACHED THE NORTHERN TIP OF THE CNMI. && .DISCUSSION... VISIBLE SATELLITE IMAGERY THIS AFTERNOON SHOWS DECELERATION ON THE SHEAR LINE'S SOUTHEASTWARD MOVEMENT. JUDGING BY ITS CURRENT SPEED...IT COULD ARRIVE AT SAIPAN ON SUNDAY EVENING AND OVER GUAM BY MONDAY MORNING. HAVE INCREASED CLOUDS AND WINDS THRU MONDAY NIGHT DURING THE IMPACT OF THE SHEAR LINE. DECIDED NOT TO ADD SCATTERED SHOWERS JUST YET...DAY SHIFT ON SUNDAY WILL HAVE BETTER IDEA ON THE FUTURE STATUS OF THE SHEAR LINE. WITH THE RIDGE OF HIGH PRESSURE DRIFTING EAST OF JAPAN MIDWEEK...DECREASING SURFACE CONVERGENCE SHOULD CAUSE THE SHEAR LINE TO DISSIPATE NEAR THE MARIANAS. && .MARINE... SWELLS GENERATED BY NEAR-GALE WINDS NORTHWEST OF A SHEAR LINE ARE GOING TO INTRODUCE RISING SURF ALONG WEST AND NORTH FACING SHORES OF THE MARIANAS BY MONDAY MORNING. SIMULTANEOUSLY...SWELLS AND WIND WAVES FROM NORTHEAST WINDS SOUTH OF THE SHEAR LINE WILL ALSO CREATE SIMILAR PHENOMENA FOR THE EAST FACING SHORES. COMBINED SEAS OF 5 TO 6 FEET WILL BUILD TO AROUND 8 FEET BY MONDAY. && .EASTERN MICRONESIA... A PERSISTENT MID- TO UPPER-LOW SOUTH OF MIDWAY ISLAND HAS REACHED DOWN TO THE SURFACE AND TRANSFORMED INTO A STRONG CUT-OFF LOW PRESSURE SYSTEM. THIS SYSTEM HAS ENGENDERED A SURFACE TROUGH EXTENDING SOUTHWARD TO JUST EAST OF THE MARSHALL ISLANDS. THIS IN TERN IS CREATING A GENTLE WIND REGIME WITH PLEASANT CONDITIONS OVER MAJURO. FARTHER WEST...A DRY MID TO UPPER-LEVEL AIR MASS WILL CONTINUE TO KEEP SHOWERS AT ISOLATED CATEGORY OVER BOTH KOSRAE AND POHNPEI THRU SUNDAY NIGHT. THE DOME OF HIGH PRESSURE CURRENTLY NORTHWEST OF WAKE ISLAND IS SHIFTING EASTWARD AND WILL ENHANCE A LIGHT SOUTHERLY FLOW OVER EASTERN MICRONESIA...PROMOTING MORE DRY WEATHER INTO MIDWEEK. && .WESTERN MICRONESIA... DRY TRADE-WIND REGIME PREVAILS ACROSS THIS AREA. LIGHT TO MODERATE SURFACE WINDS AND ISOLATED SHOWERS AREA EXPECTED THRU LONGER TERM. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...NONE. MARIANAS WATERS...NONE. && $$ CHAN/SIMPSON +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 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.