From owner-wx-tropl@LISTSERV.ILLINOIS.EDU Tue Dec 28 04:43:00 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 oBRKgxDn001073 for ; Tue, 28 Dec 2010 04:43:00 +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 oBRKRJ0U000588; Mon, 27 Dec 2010 14:42:40 -0600 (CST) Received: by LISTSERV.ILLINOIS.EDU (LISTSERV-TCP/IP release 14.5) with spool id 4893243 for WX-TROPL@LISTSERV.ILLINOIS.EDU; Mon, 27 Dec 2010 14:42:40 -0600 Received: from relay05.cites.uiuc.edu (relay05.cites.uiuc.edu [128.174.4.40]) by vacuum.cso.uiuc.edu (8.14.2/8.14.2) with ESMTP id oBRKgeZw024136 for ; Mon, 27 Dec 2010 14:42:40 -0600 (CST) Received: from weather3.admin.niu.edu (weather3.admin.niu.edu [131.156.8.48]) by relay05.cites.uiuc.edu (8.14.4/8.14.2) with ESMTP id oBRKgXi3022207 for ; Mon, 27 Dec 2010 14:42:40 -0600 (CST) Received: by weather3.admin.niu.edu (Postfix, from userid 501) id 989C03FE0019; Mon, 27 Dec 2010 14:42:33 -0600 (CST) X-Proofpoint-Spam-Reason: safe Message-ID: <20101227204233.989C03FE0019@weather3.admin.niu.edu> Date: Mon, 27 Dec 2010 14:42:33 -0600 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 579 FXPQ60 PGUM 272042 AFDPQ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TIYAN GU 642 AM CHST TUE DEC 28 2010 .SYNOPSIS...A FEW SHOWERS COULD BE SEEN ON RADAR THIS MORNING OVER THE LOCAL AREA. SATELLITE SHOWS MAINLY HIGH LEVEL CLOUDS COVERING THE MARIANAS. EXPECT MOSTLY CLOUDY SKIES TODAY WITH ISOLATED SHOWERS. A SHEAR LINE WILL ENTER THE AREA THIS WEEKEND. && .DISCUSSION...LITTLE CHANGE MADE TO FORECAST. GFS...GFSE AND UKMET KEEP THE WINDS NORTHEAST DURING THE DAY BECOMING EASTERLY BY TONIGHT. GFS AND UKMET BOTH SHOW A TROUGH OF LOW PRESSURE IN THE WIND FIELD JUST TO THE WEST OF THE MARIANAS TONIGHT. GFSE KEEPS SOME RELATIVE VORTICITY OVER THE AREA TONIGHT...SO PERIODS OF SHOWERS ARE POSSIBLE. MODEL 700 MB RH GREATER THAN 70 PERCENT ARE PREDICTED TO BE NORTH AND WEST OF THE MARIANAS TONIGHT SO ANY SCATTERED SHOWERS THAT DO DEVELOP WILL PROBABLY BE THERE WHILE ISOLATED WILL PREVAIL ACROSS THE ISLANDS. MODELS STILL DEPICT A SHEAR LINE MOVING SOUTHWARD AND PASSING ACROSS THE LOCAL AREA ON SATURDAY. THE PASSAGE WILL BE DURING THE DAY FOR TINIAN AND SAIPAN AND THE NIGHT FOR GUAM AND ROTA. WINDS WILL TURN NORTHEAST. GFS DEPICTS THAT THE SHEAR LINE WILL MAKE IT ONLY AS FAR SOUTH AS GUAM. IT REMAINS OVER THE SOUTHERN MARIANAS WITH CLOUDINESS PERSISTING THROUGH AT LEAST THROUGH TUESDAY. IT IS POSSIBLE THAT PERIODS OF SCATTERED SHOWERS ARE POSSIBLE SATURDAY THROUGH TUESDAY ASSOCIATED WITH THE SHEAR LINE...BUT WILL LEAVE IT OUT OF THE FORECAST FOR NOW UNTIL MORE IS KNOWN. && .MARINE... THE NORTHWEST SWELL AND EAST SWELL WILL PERSIST THROUGH THE FORECAST. THE EAST TRADE-WIND SWELL WILL DECREASE DURING THE FORECAST FROM 6 FEET TODAY TO 5 FEET ON SATURDAY. THE NORTHWEST SWELL WILL BECOME THE MORE INTERESTING SWELL BY THE WEEKEND. THE NORTHWEST SWELL WILL BE ABOUT TWO FEET TODAY INCREASING BRIEFLY TO FIVE FEET WEDNESDAY NIGHT THEN DROP TO THREE FEET THURSDAY NIGHT. THIS LULL WILL BE SHORT LIVED AS THE SWELL WILL INCREASE TO FOUR FEET AGAIN ON FRIDAY. A MAJOR INCREASE WILL OCCUR BY THE WEEKEND AS STRONG WINDS OVER THE NORTHWEST PACIFIC WILL PUSH LARGE SWELLS SOUTHEASTWARD. THE LARGER SWELLS WILL ENTER THE AREA SATURDAY NIGHT BECOMING 11 FEET ON SUNDAY NIGHT. IF THE MODELS ARE ACCURATE AND THIS 11 FOOT SWELL DOES IN-FACT OCCUR THAN SURF MAY REACH 15 FEET ON SOME NORTH FACING REEFS SUNDAY NIGHT AND MONDAY. THIS SITUATION WILL BE WATCHED AND IF THIS PANS OUT THAN ADVISORIES WILL BE NEEDED. && .EASTERN MICRONESIA... THE LINE OF CONVECTION HAS SHIFTED NORTHWARD SLIGHTLY AND NOW SITS NORTH OF KOSRAE EASTWARD ACROSS KWAJALEIN AND MAJURO AND ONWARD TO THE DATELINE. HAVE EXTENDED SCATTERED SHOWERS AT MAJURO INTO TONIGHT FOLLOWING MODEL GUIDANCE OF SHOWERS LINGERING IN THE AREA BEFORE DISSIPATING. SHOWERS CONTINUE TO PROGRESS TOWARD POHNPEI AND SCATTERED SHOWERS SHOULD ARRIVE AROUND NOON TODAY. GFS INDICATES DIMINISHING CONVECTIVE ACTIVITY LATER TONIGHT. AT THE MOMENT ONLY GFS40 POINTS TO A REDEVELOPED TRADE-WIND TROUGH BETWEEN POHNPEI AND THE MARSHALLS LATER THIS WEEK SO WILL KEEP ONLY ISOLATED SHOWERS IN THE FORECAST FOR NOW. && .WESTERN MICRONESIA... NOW THAT THE TROUGH NEAR CHUUK IS BEGINNING TO PASS WEST...SHOWERS ARE BECOMING BETTER DEVELOPED WEST OF CHUUK. TODAY SHOULD SEE JUST ISOLATED SHOWERS BEFORE SCATTERED SHOWERS MOVE IN LATE TONIGHT AS A TRADE-WIND TROUGH APPROACHES FROM THE EAST. SHOWERS SHOULD DROP BACK TO ISOLATED WEDNESDAY AS THE FOCUS OF CONVECTION DROPS SOUTH OF CHUUK. DEEP CONVECTION HAS SUBSIDED NEAR YAP AND PALAU OVERNIGHT BUT LOW-LEVEL CONVERGENCE NORTH OF A NEAR- EQUATORIAL TROUGH WILL BEGIN TO TRIGGER ANOTHER ROUND OF SHOWERS FOR WEDNESDAY NIGHT AND THURSDAY AT BOTH LOCATIONS. && .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. 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