From owner-wx-tropl@LISTSERV.ILLINOIS.EDU Sun Sep 5 04:48:53 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 o84KmqdR000866 for ; Sun, 5 Sep 2010 04:48:53 +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 o83JrHkF019570; Sat, 4 Sep 2010 15:48:19 -0500 (CDT) Received: by LISTSERV.ILLINOIS.EDU (LISTSERV-TCP/IP release 14.5) with spool id 3230334 for WX-TROPL@LISTSERV.ILLINOIS.EDU; Sat, 4 Sep 2010 15:48:19 -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 o84KmI65005653 for ; Sat, 4 Sep 2010 15:48:18 -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 o84KmCB3023205 for ; Sat, 4 Sep 2010 15:48:18 -0500 (CDT) Received: by weather3.admin.niu.edu (Postfix, from userid 501) id 20CB8405001F; Sat, 4 Sep 2010 15:48:12 -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-1009040148 X-Spam-OrigSender: ldm@weather3.admin.niu.edu X-Spam-Bar: Message-ID: <20100904204812.20CB8405001F@weather3.admin.niu.edu> Date: Sat, 4 Sep 2010 15:48:12 -0500 Reply-To: wxmaster@COX.NET Sender: WX-TROPL Tropical Storm and Hurricane WX products From: LDM Weather Subject: Western Pacific: Synoptic Discussion For The Marianas To: WX-TROPL@LISTSERV.ILLINOIS.EDU Precedence: list 999 FXPQ60 PGUM 042048 AFDPQ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TIYAN GU 648 AM CHST SUN SEP 5 2010 .SYNOPSIS...MOSTLY CLOUDY SKIES WITH A SLIGHT CHANCE OF THUNDERSTORMS TODAY AND TONIGHT. ISOLATED SHOWERS THROUGH THE FORECAST. AN UPPER-LEVEL LOW IS LOCATED NEAR 23N141E. UPPER-LEVEL DIVERGENCE ASSOCIATED WITH THIS LOW GENERATED SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS BOTH EAST AND WEST OF THE ISLANDS. && .DISCUSSION... LITTLE CHANGE TO FORECAST. CONFIDENCE IN THE FORECAST IS NOT AS HIGH AS ONE WOULD LIKE. UPPER-LEVEL LOW NORTHWEST OF THE MARIANAS HAS DUG DOWN AS FAR SOUTH AS IT PROBABLY WILL AND IS NOW MOVING WESTWARD. UPPER-LEVEL DIVERGENCE GENERATED AREAS OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS TO THE EAST AND WEST OF THE MARIANAS THIS MORNING. IF THE UPPER-LOW IS MOVING WEST WILL SOME OF THE UPPER DIVERGENCE MOVE ACROSS THE LOCAL AREA. MODELS HINT AT THIS BUT FELT ONE COULD NOT JUSTIFY PUTTING SCATTERED SHOWERS IN THE FORECAST. A SLIGHT CHANCE OF THUNDERSTORMS WAS ALREADY IN THE FORECAST THROUGH TONIGHT AND WITH THE UPPER LOW IN THE REGION FELT IT WAS BEST TO KEEP THEM IN. MODELS TRY TO DRY US OUT THROUGH THE REMAINDER OF THE FORECAST BUT THEN AGAIN THEY HAVE BEEN SAYING THAT FOR A FEW DAYS...COULD THE WET AND CLOUDY WEATHER HANG ON LONGER THAN EXPECTED. WINDS WILL BE BASIC EAST TRADE-WINDS THROUGH THE FORECAST. EVEN CONFIDENCE IN THIS...AT LEAST IN THE NEAR TERM...IS IN QUESTION. COULD THE LARGE AREA OF SHOWERS AND THUNDERSTORMS...THAT WAS TO THE EAST OF THE ISLANDS FOR MUCH OF THE MORNING...PUSH OUT AN OUTFLOW BOUNDARY. ON FRIDAY AN AREA OF SHOWERS TO THE EAST OF THE ISLANDS DID PUSH OUT AN OUTFLOW BOUNDARY WHICH MOVED OVER THE MARIANAS. WINDS ASSOCIATED WITH THE BOUNDARY BRIEFLY ELEVATED WINDS DURING FRIDAY AFTERNOON. WITH NO EVIDENCE TO SUPPORT THE EXISTENCE OF SAID BOUNDARY WILL LEAVE OUT OF FORECAST. && .MARINE... EAST TO OCCASIONALLY SOUTHEAST SWELLS OF FOUR FEET ARE ALL THAT IS EXPECTED THROUGH THE FORECAST. RIP CURRENT RISK WILL REMAIN LOW THROUGH AT LEAST MIDWEEK. && .EASTERN MICRONESIA... CONVECTION HAS STEADILY DISSIPATED ACROSS THE AREA WHILE PUSHING FARTHER NORTH TO BETWEEN 8N AND 10N DUE TO GENTLE TO MODERATE SOUTHEAST WINDS. NEARER POHNPEI...CONVECTION DIPS TOWARD THE WSW. THIS WILL KEEP SCATTERED SHOWERS AT POHNPEI FOR THE FIRST PART OF TODAY BEFORE SHOWERS SHIFT FARTHER WEST. MODELS KEEP A WEAKENED TRADE-WIND CONVERGENCE ZONE NORTH OF POHNPEI...KOSRAE AND MAJURO FOR MUCH OF THE WEEK WITH THE EXCEPTION OF A FEW BRIEF PULSES OF INCREASED SHOWER ACTIVITY AS WEAK SURFACE TROUGHS PASS THROUGH THE REGION...BUT AT THIS POINT...MODEL GUIDANCE GIVES NO REASON TO EXPECT ANYTHING MORE THAN ISOLATED SHOWERS THROUGH THURSDAY. && .WESTERN MICRONESIA... UPPER-LEVEL DIVERGENCE NEAR CHUUK...YAP AND PALAU IS PROVIDING SUFFICIENT UPLIFT TO PRODUCE SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS. ALTHOUGH CHUUK EXPERIENCED A BRIEF ROUND OF SCATTERED SHOWERS OVERNIGHT...THE BULK OF SHOWER ACTIVITY IS EXPECTED TO REMAIN WEST TODAY. THE DRY PATTERN OVER EASTERN MICRONESIA WILL THEN SPREAD WESTWARD LIKELY KEEPING SHOWERS LIMITED TO ISOLATED FOR THE WEEK. FOR YAP AND PALAU...UPPER LEVEL CONDITIONS WILL REMAIN FAVORABLE FOR ISOLATED THUNDERSTORMS THROUGH TODAY. INCREASING LOW-LEVEL CONVERGENCE WILL TRIGGER SCATTERED SHOWERS AND POSSIBLY A FEW THUNDERSTORMS MONDAY NIGHT AND TUESDAY. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...NONE. MARIANAS WATERS...NONE. && $$ ZIOBRO/W. AYDLETT +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 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.