From owner-wx-tropl@LISTSERV.ILLINOIS.EDU Thu Sep 23 10:45:21 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 o8N2jKRU010733 for ; Thu, 23 Sep 2010 10:45:20 +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 o8MB02Ap015719; Wed, 22 Sep 2010 21:44:11 -0500 (CDT) Received: by LISTSERV.ILLINOIS.EDU (LISTSERV-TCP/IP release 14.5) with spool id 3544242 for WX-TROPL@LISTSERV.ILLINOIS.EDU; Wed, 22 Sep 2010 21:44:11 -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 o8N2iASn024814 for ; Wed, 22 Sep 2010 21:44:10 -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 o8N2i47f013818 for ; Wed, 22 Sep 2010 21:44:10 -0500 (CDT) Received: by weather3.admin.niu.edu (Postfix, from userid 501) id 1EB63405001E; Wed, 22 Sep 2010 21:44:03 -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-1009220268 X-Spam-OrigSender: ldm@weather3.admin.niu.edu X-Spam-Bar: Message-ID: <20100923024404.1EB63405001E@weather3.admin.niu.edu> Date: Wed, 22 Sep 2010 21:44:03 -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 13w Warning Nr 12// To: WX-TROPL@LISTSERV.ILLINOIS.EDU Precedence: list WDPN32 PGTW 230300 MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 13W WARNING NR 12// RMKS/ 1. FOR METEOROLOGISTS. 2. 12 HOUR SUMMARY AND ANALYSIS. A. TYPHOON (TY) 13W (MALAKAS), LOCATED APPROXIMATELY 295 NM SOUTH OF IWO TO, JAPAN, HAS TRACKED WEST-NORTHWESTWARD AT 04 KNOTS AND HAS INTENSIFIED BY 15 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS IMPROVED CENTRAL CONVECTION OVER THE TIGHTLY WRAPPED LOW LEVEL CIRCULATION CENTER (LLCC). A 222113Z 37V SSMIS MICROWAVE IMAGE SHOWS THE MAJORITY OF THE DEEPEST CONVECTION IS LOCATED TO THE SOUTHEAST OF THE LLCC. THE INITIAL POSITION IS BASED ON THE AFOREMENTIONED SSMIS AND MULTISPECTRAL IMAGERY AS WELL AS POSITION ESTIMATES FROM A 222351Z ITOP VORTEX MESSAGE. THE INITIAL INTENSITY IS BASED ON PGTW AND RJTD DVORAK ESTIMATES RANGING FROM 55 TO 77 KNOTS, IN ADDITION TO THE VORTEX MESSAGE REPORTING 69 KNOT WINDS. UPPER LEVEL ANALYSIS INDICATES THAT A TROPICAL UPPER TROPOSPHERIC TROUGH (TUTT) TO THE NORTH HAS MOVED FARTHER NORTHWARD ALLOWING FOR A DECREASE IN SUBSIDENCE ALONG THE NORTHERN PERIPHERY, WHICH HAS ALLOWED FOR FURTHER INTENSIFICATION. EQUATORWARD OUTFLOW AND OUTFLOW INTO A TUTT CELL TO THE NORTHEAST REMAINS GOOD. 3. FORECAST REASONING. A. THE FORECAST REASONING HAS NOT CHANGED SINCE THE PREVIOUS PROGNOSTIC REASONING BULLETIN. B. TY 13W IS CURRENTLY TRACKING ALONG THE SOUTHWESTERN PERIPHERY OF A SUBTROPICAL STEERING RIDGE. A MID-LATITUDE, UPPER LEVEL TROUGH TO THE NORTHWEST IS EXPECTED TO CONTINUE TRACKING EASTWARD AND WEAKEN THE STEERING RIDGE TO THE NORTH WITHIN THE NEXT 12 HOURS. THIS WILL ALLOW TY MALAKAS TO TURN POLEWARD. TY 13W IS EXPECTED TO CONTINUE INTENSIFYING AS POLEWARD OUTFLOW IMPROVES INTO THE APPROACHING MID-LATITUDE TROUGH. AROUND TAU 36, TY 13W WILL ROUND THE RIDGE AXIS AND BEGIN TO RECURVE INTO THE MID-LATITUDE WESTERLIES. BY TAU 72, THE SYSTEM IS FORECAST TO TRANSITION FULLY INTO AN INTENSE EXTRATROPICAL LOW AS IT GAINS THE UPPER LEVEL SUPPORT OF THE APPROACHING TROUGH. NUMERICAL MODEL GUIDANCE IS IN VERY GOOD AGREEMENT. THEREFORE, THIS FORECAST IS IN AGREEMENT WITH THE 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.