From owner-wx-tropl@LISTSERV.ILLINOIS.EDU Fri Oct 29 10:28:27 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 o9T2SP9W010282 for ; Fri, 29 Oct 2010 10:28:26 +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 o9SLvlCT021767; Thu, 28 Oct 2010 21:28:16 -0500 (CDT) Received: by LISTSERV.ILLINOIS.EDU (LISTSERV-TCP/IP release 14.5) with spool id 4112144 for WX-TROPL@LISTSERV.ILLINOIS.EDU; Thu, 28 Oct 2010 21:28:15 -0500 Received: from relay07.cites.uiuc.edu (relay07.cites.uiuc.edu [128.174.4.73]) by vacuum.cso.uiuc.edu (8.14.2/8.14.2) with ESMTP id o9T2SFX2019820 for ; Thu, 28 Oct 2010 21:28:15 -0500 (CDT) Received: from weather3.admin.niu.edu (weather3.admin.niu.edu [131.156.8.48]) by relay07.cites.uiuc.edu (8.14.4/8.14.2) with ESMTP id o9T2S9sb018045 for ; Thu, 28 Oct 2010 21:28:15 -0500 (CDT) Received: by weather3.admin.niu.edu (Postfix, from userid 501) id 1287D4050021; Thu, 28 Oct 2010 21:28:08 -0500 (CDT) X-Proofpoint-Spam-Reason: safe Message-ID: <20101029022809.1287D4050021@weather3.admin.niu.edu> Date: Thu, 28 Oct 2010 21:28:08 -0500 Reply-To: wxmaster@COX.NET Sender: WX-TROPL Tropical Storm and Hurricane WX products From: SIU Weather Processor Subject: Pacific-NW: Subj/prognostic Reasoning For Typhoon 16w Warning Nr 29// To: WX-TROPL@LISTSERV.ILLINOIS.EDU Precedence: list WDPN32 PGTW 290300 MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 16W WARNING NR 29// RMKS/ 1. FOR METEOROLOGISTS. 2. 12 HOUR SUMMARY AND ANALYSIS. A. TYPHOON (TY) 16W (CHABA), LOCATED APPROXIMATELY 660 NM SOUTHWEST OF TOKYO, JAPAN, HAS TRACKED NORTHEASTWARD AT 11 KNOTS. ANIMATED INFRARED SATELLITE IMAGERY AND A 282201 SSMIS MICROWAVE IMAGE SHOW A SIGNIFICANT DECREASE IN DEEP CONVECTION AND LOSS OF THE EYE WITHIN THE LAST 12 HOURS. STRATOCUMULOUS CLOUDS CAN BE SEEN IN VISIBLE IMAGERY WRAPPING INTO THE SYSTEM FROM THE NORTHWESTERN SIDE AND A TOTAL PRECIPITABLE WATER PRODUCT DEPICTS OVERALL DECREASING MOISTURE CONTENT. THE CURRENT POSITION IS BASED ON A PGTW FIX AND RADAR FIX FROM JAPAN WITH POOR CONFIDENCE. THE CURRENT INTENSITY IS BASED ON PGTW, KNES, AND RJTD DVORAK ESTIMATES RANGING FROM 90 TO 102 KNOTS. ENVIRONMENTAL ANALYSIS INDICATES THE SYSTEM IS LOCATED IN AN AREA OF HIGH VERTICAL WIND SHEAR (30 TO 35 KNOTS) AND MARGINAL SEA SURFACE TEMPERATURES (26 DEGREES CELSIUS). TY 16W CONTINUES TO MAINTAIN ENHANCED POLEWARD OUTFLOW INTO AN UPPER LEVEL MID-LATITUDE TROUGH TO THE NORTHEAST. TY CHABA IS CURRENTLY TRACKING ALONG THE NORTHWESTERN PERIPHERY OF A SUBTROPICAL STEERING RIDGE ANCHORED SOUTHEAST OF JAPAN. 3. FORECAST REASONING. A. THERE IS NO CHANGE IN THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TY 16W WILL WEAKEN AS IT CONTINUES TO TRACK NORTHEASTWARD DUE TO DECEASING OCEAN HEAT CONTENT AND INCREASING VERTICAL WIND SHEAR ASSOCIATED WITH THE BAROCLINIC ZONE, JUST SOUTH OF MAINLAND JAPAN. WITHIN 12 HOURS, TY CHABA IS FORECAST TO INITIALLY INTERACT WITH THE MID-LATITUDE WESTERLIES AND BEGIN EXTRATROPICAL TRANSITION. AN UPPER AIR SOUNDING FROM KAGOSHIMA, JAPAN (31.6N 130.6E) INDICATES VERY STRONG UPPER LEVEL WESTERLIES. BY TAU 36, TY 16W SHOULD BECOME ABSORBED BY THE BAROCLINIC ZONE, AND FULLY TRANSITION INTO AN EXTRATROPICAL LOW. MODEL GUIDANCE IS IN GOOD AGREEMENT, EXCEPT FOR GFDN, WHICH ERRONEOUSLY TRACKS THE SYSTEM NORTHWARD INTO THE MID- LATITUDE FLOW. THIS FORECAST IS SOUTH OF MODEL CONSENSUS TO ACCOUNT FOR THE GFDN TRACK ERROR AND IS FASTER THAN CONSENSUS TO ACCOUNT FOR THE TENDENCY OF THE MODEL FORECAST TRACKS TO BE SLOW IN A RECURVATURE SCENARIO.// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 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.