From owner-wx-tropl@LISTSERV.ILLINOIS.EDU Fri Sep 24 22:37:33 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 o8OEbVYf016365 for ; Fri, 24 Sep 2010 22:37:32 +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 o8OE1c2W028356; Fri, 24 Sep 2010 09:37:21 -0500 (CDT) Received: by LISTSERV.ILLINOIS.EDU (LISTSERV-TCP/IP release 14.5) with spool id 3570778 for WX-TROPL@LISTSERV.ILLINOIS.EDU; Fri, 24 Sep 2010 09:37:20 -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 o8OEbKXw003326 for ; Fri, 24 Sep 2010 09:37:20 -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 o8OEbDR5018694 for ; Fri, 24 Sep 2010 09:37:20 -0500 (CDT) Received: by weather3.admin.niu.edu (Postfix, from userid 501) id 8961E405001F; Fri, 24 Sep 2010 09:37:13 -0500 (CDT) X-Spam-Score: 0 X-Spam-Details: rule=no-quarantine_notspam policy=no-quarantine score=0 spamscore=0 ipscore=0 phishscore=0 bulkscore=80 adultscore=0 classifier=spam adjust=0 reason=mlx engine=5.0.0-1005130000 definitions=main-1009240091 X-Spam-OrigSender: ldm@weather3.admin.niu.edu X-Spam-Bar: Message-ID: <20100924143713.8961E405001F@weather3.admin.niu.edu> Date: Fri, 24 Sep 2010 09:37:13 -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 Tropical Storm 13w Warning Nr 18// To: WX-TROPL@LISTSERV.ILLINOIS.EDU Precedence: list WDPN32 PGTW 241500 MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 13W WARNING NR 18// RMKS/ 1. FOR METEOROLOGISTS. 2. 12 HOUR SUMMARY AND ANALYSIS. A. TYPHOON (TY) 13W (MALAKAS), LOCATED APPROXIMATELY 75 NM NORTH-NORTHWEST OF CHICHI JIMA, JAPAN, HAS TRACKED NORTH- NORTHEASTWARD AT 23 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY AND A 241010Z SSMIS 91 GHZ MICROWAVE PASS DEPICT A 50 NM EYE WITH DEEP CONVECTIVE BANDING WRAPPING INTO THE CENTER FROM THE SOUTHEASTERN QUADRANT. THE CURRENT POSITION IS BASED ON A 241132Z PGTW EYE FIX AND A MICROWAVE EYE IN THE AFOREMENTIONED SSMIS PASS WITH GOOD CONFIDENCE. THE CURRENT INTENSITY IS HELD AT 90 KNOTS BASED ON DVORAK CURRENT INTENSITY (CI) ESTIMATES FROM PGTW AND RJTD OF 90 KNOTS. ANIMATED WATER VAPOR IMAGERY SHOWS ENHANCED POLEWARD OUTFLOW ASSOCIATED WITH A DIGGING MID-LATITUDE TROUGH TO THE NORTHWEST, HOWEVER, UPPER-LEVEL CONVERGENCE SOUTHWEST OF THE SYSTEM IS HINDERING EQUATORWARD OUTFLOW. 3. FORECAST REASONING. A. THE FORECAST REASONING HAS NOT CHANGED SINCE THE PREVIOUS PROGNOSTIC REASONING BULLETIN. B. TY 13W IS CURRENTLY TRACKING ALONG THE WESTERN PERIPHERY OF A DEEP LAYER SUBTROPICAL STEERING RIDGE. NEAR TAU 12 THE SYSTEM IS FORECAST TO BEGIN EXTRA-TROPICAL TRANSITION AND GRADUALLY WEAKEN AS IT ENCOUNTERS INCREASED VERTICAL ASSOCIATED WITH THE MID-LATITUDE WESTERLIES. DURING EXTRA-TROPICAL TRANSITION (ET), TY 13W IS EXPECTED TO REMAIN INTENSE, AS STRONG UPPER LEVEL DIFFLUENCE AND A SHARP TEMPERATURE GRADIENT ASSOCIATED WITH THE DIGGING UPPER LEVEL TROUGH TO THE WEST SUPPORT STRONG BAROCLINIC DEVELOPMENT. TY 13W IS EXPECTED TO COMPLETE ET BY TAU 36 AND CONTINUE TRACKING NORTHEASTWARD AS AN INTENSE EXTRA-TROPICAL LOW. NUMERICAL MODEL GUIDANCE REMAINS IN EXCELLENT AGREEMENT; THEREFORE THIS FORECAST IS CLOSE TO MODEL CONSENSUS.// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 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.