From owner-wx-tropl@LISTSERV.ILLINOIS.EDU Fri Oct 22 22:34:25 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 o9MEYOuV030975 for ; Fri, 22 Oct 2010 22:34:25 +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 o9LJQBtr014749; Fri, 22 Oct 2010 09:34:13 -0500 (CDT) Received: by LISTSERV.ILLINOIS.EDU (LISTSERV-TCP/IP release 14.5) with spool id 3996463 for WX-TROPL@LISTSERV.ILLINOIS.EDU; Fri, 22 Oct 2010 09:34:13 -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 o9MEYDu5010535 for ; Fri, 22 Oct 2010 09:34:13 -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 o9MEY6d2024732 for ; Fri, 22 Oct 2010 09:34:12 -0500 (CDT) Received: by weather3.admin.niu.edu (Postfix, from userid 501) id 6B405108B0002; Fri, 22 Oct 2010 09:34:06 -0500 (CDT) X-Proofpoint-Spam-Reason: safe Message-ID: <20101022143406.6B405108B0002@weather3.admin.niu.edu> Date: Fri, 22 Oct 2010 09:34:06 -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 Depression 16w Warning Nr 05// To: WX-TROPL@LISTSERV.ILLINOIS.EDU Precedence: list WDPN32 PGTW 221500 MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 16W WARNING NR 05// RMKS/ 1. FOR METEOROLOGISTS. 2. 12 HOUR SUMMARY AND ANALYSIS. A. TROPICAL DEPRESSION (TD) 16W, LOCATED APPROXIMATELY 755 NM SOUTHEAST OF KADENA, HAS TRACKED WESTWARD AT 12 KNOTS OVER THE PAST SIX HOURS. BASED ON THE CURRENT INFRARED SATELLITE PRESENTATION THE SYSTEM MAINTAINS MARGINAL CLASSIFICATION AS A TROPICAL DEPRESSION. A TROPICAL UPPER LEVEL TROPOSPHERIC TROUGH (TUTT) HAS MOVED OVERHEAD AND HAS DEGRADED ENVIRONMENTAL CONDITIONS CONSIDERABLY. THE LOW LEVEL CIRCULATION (LLCC) HAS BEEN LEFT EXPOSED AND WEAKENED BASED ON LOW LEVEL CLOUD LINES. THERE IS ONLY LIMITED EVIDENCE OF A LINGERING LLCC IN A 220754Z SSMIS 91H MICROWAVE IMAGE. DEEP CONVECTION HAS BEEN DISPLACED SOUTH OF THE PERCEIVED LOCATION OF THE LLCC, AND APPEARS TO BE FLANKING THE OUTER PERIPHERY OF THE CIRCULATION VICE THE CENTRAL TURNING. DVORAK INTENSITY ESTIMATES FROM RJTD AND PGTW ONLY INDICATE A 25 KNOT SYSTEM. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE IN THE FORECAST PHILOSOPHY SINCE THE PREVIOUS BULLETIN. HOWEVER, THERE CONTINUES TO BE A HIGH DEGREE OF UNCERTAINTY IN THE EXTENDED TRACK AND INTENSITY FORECAST. B. TD 16W IS CURRENTLY TRACKING ALONG A LOW-LEVEL SUBTROPICAL RIDGE POSITIONED TO THE NORTH. THE SYSTEM WILL CONTINUE TO TRACK WESTWARD ALONG THIS RIDGE AND WILL STRUGGLE TO INTENSIFY TO MIMIMAL TROPICAL STORM STRENGTH IN THE SHORT TERM. UPPER LEVEL CONDITIONS ARE FORECAST TO IMPROVE WITHIN THE NEXT FEW DAYS. THIS WILL ALLOW THE SYSTEM TO ORGANIZE AND INTENSIFY, ASSUMING IT HOLDS TOGETHER IN THE INTERIM. C. ONCE THE SYSTEM STRENGTHENS IT WILL BEGIN TO TRACK ALONG THE DEEP LAYER RIDGE TO THE NORTHEAST. AN UPPER LEVEL LONGWAVE TROUGH WILL ERODE THE RIDGE AS IT PASSES TO THE EAST AND INITIATE A POLEWARD TRACK. HOWEVER, A LOW LEVEL NORTHEASTERLY SURGE WILL MITIGATE AGGRESSIVE RECURVATURE AND INTENSIFICATION (DUE TO STRONG DIRECTIONAL SHEAR). THE FORECAST ACCORDINGLY LIES SOUTH OF THE MODEL CONSENSUS BEYOND TAU 72 TO ACCOUNT FOR THE EFFECTS OF THIS SURGE EVENT AND THE ECMWF, NOGAPS, AND GFS TRACKERS PULLING THE SYSTEM NORTH TOO AGGRESSIVELY.// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 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.