From owner-wx-tropl@LISTSERV.ILLINOIS.EDU Wed Oct 6 18:03:33 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 o96A3Wic029824 for ; Wed, 6 Oct 2010 18:03:33 +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 o95Lbo9a025335; Wed, 6 Oct 2010 05:03:16 -0500 (CDT) Received: by LISTSERV.ILLINOIS.EDU (LISTSERV-TCP/IP release 14.5) with spool id 3764302 for WX-TROPL@LISTSERV.ILLINOIS.EDU; Wed, 6 Oct 2010 05:03:16 -0500 Received: from relay04.cites.uiuc.edu (relay04.cites.uiuc.edu [128.174.196.5]) by vacuum.cso.uiuc.edu (8.14.2/8.14.2) with ESMTP id o96A3Gp5029275 for ; Wed, 6 Oct 2010 05:03:16 -0500 (CDT) Received: from weather3.admin.niu.edu (weather3.admin.niu.edu [131.156.8.48]) by relay04.cites.uiuc.edu (8.14.4/8.14.2) with ESMTP id o96A39TD019647 for ; Wed, 6 Oct 2010 05:03:15 -0500 (CDT) Received: by weather3.admin.niu.edu (Postfix, from userid 501) id 391E6405016A; Wed, 6 Oct 2010 05:03:08 -0500 (CDT) X-Proofpoint-Spam-Reason: safe Message-ID: <20101006100309.391E6405016A@weather3.admin.niu.edu> Date: Wed, 6 Oct 2010 05:03:08 -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 619 FXPQ60 PGUM 061003 AAA AFDPQ AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE TIYAN GU 803 PM CHST WED OCT 6 2010 .UPDATE FORECAST FOR INCREASING SHOWERS AND THUNDERSTORMS... && .SYNOPSIS... SHOWERS AND THUNDERSTORMS ARE INCREASING ENOUGH TO UPDATE FORECAST. WHILE MOST OF THE PRECIPITATION IS OVER GUAM AND ROTA FELT ENOUGH IS FALLING NORTH OF THAT TO INCLUDE ALL ZONES. IT IS ALSO POSSIBLE THAT THE SHOWER ACTIVITY MAY END BY MIDNIGHT...BUT DID NOT WANT TO SPLIT HAIRS AND LEAVE MIDNIGHT SHIFT WITH AN UPDATE. AT ANY RATE PAST FORECAST BRINGS IN SHOWERS BY EARLY MORNING SO IF THERE IS A BREAK IN THE SHOWER ACTIVITY IT PROBABLY WILL BE BRIEF. .PREV DISCUSSION... /ISSUED 447 PM CHST WED OCT 6 2010/ SYNOPSIS...SATELLITE IMAGERY AND RADAR SHOW AN EXTENSIVE AREA OF MID TO UPPER-LEVEL CLOUDINESS COVERING THE MARIANAS THIS AFTERNOON...PRIMARILY RELATED TO THE POSITIONING OF AN UPPER TROUGH WEST OF THE ISLANDS. IN ADDITION...INCREASED SHOWER ACTIVITY ASSOCIATED WITH A WEAK WESTWARD MOVING TRADE-WIND DISTURBANCE BETWEEN GUAM AND CHUUK IS EXPECTED TO AFFECT THE GUAM AND ROTA ZONES TONIGHT INTO TOMORROW. LITTLE THUNDERSTORM ACTIVITY IS SEEN ON THE RADAR BUT THIS MAY CHANGE OVER NIGHT. DISCUSSION...KEPT MOST OF THE IMMINENT WEATHER RESTRICTED TO THE SOUTHERN ZONES AS MODELS ARE UNCLEAR HOW FAR NORTH THE SHOWERS WILL PUSH. THE WATER VAPOR IMAGERY SHOWS THE EFFECT OF THE UPPER LEVEL RIDGING OVER THE MARIANAS BY INCREASING THE CLOUD COVER NORTHWARD OVER THE ISLANDS...HOWEVER THE SHOWER ACTIVITY IN THE RADAR SEEMS TO BE FOLLOWING WHAT THE NWP MODELS ARE PREDICTING BY REMAINING PRIMARILY SOUTH OF GUAM. ANOTHER WEATHER MAKER APPEARS IN THE NOGAPS AND UKMET AND SOMEWHAT WEAKER IN THE ECMWF AND GFS RUNS TO BE ASSOCIATED WITH THE CONVECTIVE ACTIVITY CURRENTLY ALONG 160E...JUST SOUTHEAST OF ANOTHER UPPER LEVEL TUTT. THIS FEATURE IN CONJUNCTION WITH A ITCZ-RELATED DISTURBANCE...CURRENTLY BETWEEN POHNPEI AND KWAJALEIN...SEEMS LIKELY TO AFFECT THE MARIANAS BY LATE FRIDAY INTO SUNDAY. WITH THE UNCERTAINTY IN TIMING AND NORTHWARD PUSH FOR THIS PARTICULAR FEATURE...I FIGURED IT BEST TO JUST INCREASE THE CLOUDINESS FOR NOW AND TO ADD THE PHRASE...SLIGHT CHANCE OF THUNDERSTORMS...UNTIL WE GET A BETTER IDEA WHAT IT WANTS TO DO. EASTERN MICRONESIA... SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS EXTENDED ACROSS MUCH OF EASTERN MICRONESIA TODAY BUT IS SHOWING GRADUAL SIGNS OF STRATIFICATION NORTH AND EAST OF KOSRAE AND SOME CLEARING ACROSS THE MARSHALLS. SHOWERS ARE EXPECTED TO TAPER OVERNIGHT...MOVING WEST OF POHNPEI WITH ISOLATED SHOWERS REMAINING ACROSS THE REGION. HOWEVER...ANOTHER LARGE AREA OF SHOWERS IS CROSSING THE DATELINE AND WILL BRING SCATTERED SHOWERS TO MAJURO TOMORROW NIGHT. MODELS KEEP MAJURO WET INTO THE WEEKEND BUT INDICATES A NORTHWARD DRIFT OF THE ITCZ...KEEPING MOST OF THE SHOWERS NORTH OF KOSRAE AND POHNPEI. WESTERN MICRONESIA... SCATTERED SHOWERS FROM THE EAST ALSO COVERED MUCH OF WESTERN MICRONESIA FROM PALAU TO CHUUK. CHUUK WILL SEE ISOLATED SHOWERS OVERNIGHT BEFORE MORE SHOWERS NEAR POHNPEI PASS THROUGH. SCATTERED SHOWERS WILL REMAIN NEAR KOROR TONIGHT BUT WILL HANG AROUND YAP THROUGH FRIDAY AS SHOWERS SEEM TO BE FOLLOWING A PATH BETWEEN YAP AND GUAM.. MOVING INTO THE WEEKEND...THE MODELS TEND TO BREAK THE CURRENT PATTERN...KILLING THE WINDS ACROSS THE REGION. GFS HAS A SIMILAR PATTERN EXTENDING TO NEAR KOSRAE. AT THIS TIME...LIGHT AND VARIABLE WINDS WILL BE IN THE FORECAST FRIDAY NIGHT FOR YAP AND SATURDAY FOR PALAU. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...NONE. MARIANAS WATERS...NONE. && $$ ZIOBRO/WILLIAMS +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 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.