From owner-wx-tropl@LISTSERV.ILLINOIS.EDU Thu Sep 16 22:14:27 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 o8GEEPph003683 for ; Thu, 16 Sep 2010 22:14:26 +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 o8G50Bsb023157; Thu, 16 Sep 2010 09:14:13 -0500 (CDT) Received: by LISTSERV.ILLINOIS.EDU (LISTSERV-TCP/IP release 14.5) with spool id 3423786 for WX-TROPL@LISTSERV.ILLINOIS.EDU; Thu, 16 Sep 2010 09:14:13 -0500 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 o8GEEDtp003346 for ; Thu, 16 Sep 2010 09:14:13 -0500 (CDT) 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 o8GEE6Ti005105 for ; Thu, 16 Sep 2010 09:14:13 -0500 (CDT) Received: by weather3.admin.niu.edu (Postfix, from userid 501) id 1580D405001E; Thu, 16 Sep 2010 09:14:05 -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=0 adultscore=0 classifier=spam adjust=0 reason=mlx engine=5.0.0-1005130000 definitions=main-1009160050 X-Spam-OrigSender: ldm@weather3.admin.niu.edu X-Spam-Bar: Message-ID: <20100916141406.1580D405001E@weather3.admin.niu.edu> Date: Thu, 16 Sep 2010 09:14:05 -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 12w Warning Nr 08// To: WX-TROPL@LISTSERV.ILLINOIS.EDU Precedence: list WDPN31 PGTW 161500 MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 12W WARNING NR 08// RMKS/ 1. FOR METEOROLOGISTS. 2. 12 HOUR SUMMARY AND ANALYSIS. A. TYPHOON (TY) 12W (FANAPI), LOCATED APPROXIMATELY 270 NM SOUTH OF OKINAWA, JAPAN, HAS TRACKED NORTH-NORTHEASTWARD AT 03 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY AND A 161145Z SSMIS IMAGE DEPICT A CONSOLIDATING LOW-LEVEL CIRCULATION CENTER (LLCC) WITH A MICROWAVE EYE FEATURE AND IMPROVED CONVECTIVE BANDING OVER THE EASTERN SEMI-CIRCLE. ANIMATED WATER VAPOR IMAGERY SHOWS IMPROVED POLEWARD OUTFLOW ASSOCIATED WITH A MIDLATITUDE SHORT-WAVE TROUGH PROPAGATING EASTWARD INTO CENTRAL JAPAN. BASED ON SEVERAL HIGH RESOLUTION MICROWAVE IMAGES (160707Z TRMM, 160956Z SSMIS AND 161145Z SSMIS), TY 12W IS SLOWING AND TURNING NORTHWARD TO NORTHWESTWARD. RECENT INFRARED IMAGERY SUGGESTS THAT THE SYSTEM MAY EVEN BE BEGINNING TO TRACK WEST-NORTHWESTWARD AS ANTICIPATED. THERE IS GOOD CONFIDENCE IN THE CURRENT POSITION BASED ON THE WELL-DEFINED LLCC IN THE 161145Z SSMIS IMAGE. THE SYSTEM HAS BEEN UPGRADED TO TYPHOON STRENGTH (65 KNOTS) BASED ON DVORAK ESTIMATES OF 65 KNOTS FROM PGTW AND RJTD, AND ON THE MUCH IMPROVED SATELLITE SIGNATURE. 3. FORECAST REASONING. A. NO CHANGE IN FORECAST PHILOSOPHY AND TRACK SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. THE 16/00Z 500MB ANALYSIS AS WELL AS RECENT SATELLITE IMAGERY INDICATE THAT THE SUBTROPICAL RIDGE IS RAPIDLY BUILDING ACROSS THE EAST CHINA SEA. THE MIDLATITUDE SHORT-WAVE TROUGH, WHICH HAD A SHORT-TERM INFLUENCE ON THE TRACK IS PROPAGATING NORTHEASTWARD INTO CENTRAL JAPAN. THEREFORE, THE SUBTROPICAL STEERING RIDGE POSITIONED NORTH OF THE SYSTEM IS EXPECTED TO BECOME THE DOMINANT STEERING INFLUENCE OVER THE NEXT 12-24 HOURS. THIS WILL ALLOW THE SYSTEM TO TRACK WESTWARD AND TO ACCELERATE UP TO 8-10 KNOTS. TY 12W IS EXPECTED TO MAKE LANDFALL OVER TAIWAN PRIOR TO TAU 72. FANAPI SHOULD CONTINUE TO INTENSIFY AT A 15-20 KNOT PER DAY RATE BUT IS EXPECTED TO PEAK AT 90 KNOTS BETWEEN TAU 36 AND 48 DUE TO INCREASING NORTHERLY VERTICAL WIND SHEAR ASSOCIATED WITH THE BUILDING RIDGE. THE AVAILABLE NUMERICAL GUIDANCE IS IN TIGHT AGREEMENT WITH THE EXCEPTION OF WBAR, WHICH IS THE ONLY MODEL INDICATING A TRACK NORTH OF TAIWAN (REMAINS THE ONLY OUTLIER). ALL THE OTHER MODELS TRACK THE SYSTEM OVER TAIWAN. C. IN THE EXTENDED PERIOD, TY 12W IS EXPECTED TO WEAKEN AFTER CROSSING TAIWAN BUT SHOULD MAINTAIN 55-60 KNOT INTENSITY AS IT CROSSES THE TAIWAN STRAIT. THE SYSTEM IS FORECAST TO MAKE LANDFALL OVER MAINLAND CHINA BY TAU 96 AND SHOULD DISSIPATE BY TAU 120.// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 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.