287 
fxpq60 pgum 212002 
afdpq 


Area forecast discussion 
National Weather Service tiyan GU 
602 am chst sun Nov 22 2009 


Synopsis... 
tropical disturbance 94w is centered about 550 miles southeast of Guam 
near 6n148e...moving little. It is getting better organized...and 
will likely be a tropical depression before the day is out. Only 
isolated showers are present across the marianas this morning... 
with brisk east-northeast winds. 


&& 


Discussion... 
winds associated with the trade wind surge should peak today and 
tonight at 20-25 knots...with only isolated showers expected through 
Tuesday. The future track of 94w is still uncertain...with the 
latest model consensus trending a bit south. GFS takes 94w just 
north of Rota Wednesday...while NOGAPS keeps it just south of Guam...and 
European model (ecmwf) has it passing about 150 miles south of Guam Wednesday morning. 
The outlier seems to be the UKMET...Whick keeps it west of Chuuk 
through Tuesday evening. In view of the uncertainty...have done little to 
the forecast except increase probability of precipitation for Wed/Thu. Have issued Special Weather Statement for 
the marianas. 


&& 


Marine/surf... 
have gone ahead with a Small Craft Advisory through noon Monday for 
both winds and seas...though it is marginal for both. But the 
combination of 20-25 knots winds and seas at 10 feet will make for 
rough conditions for small craft. Holding off on high surf 
advisory...as surf approaches but doesn't hit hazardous levels. 


&& 


Eastern micronesia... 
scattered showers and a few thunderstorms associated with the 
eastern limb of the monsoon trough continue over Pohnpei and Kosrae 
this morning. Expect this portion of the trough to remain fairly 
active over the next couple of periods. Then an intensifying 
tropical system...94w...will disrupt westerly flow in central 
micronesia. Easterlies will return temporarily and weak ridging 
will move west over Kosrae and Pohnpei late Monday into midweek. 
Elsewhere...trade winds will prevail over the Marshalls. Guidance 
suggests another trade disturbance will move into eastern zones by 
midweek. 


&& 


Western micronesia... 
appended heavy shower and gusty wind wording through Monday night of 
the Chuuk forecast. This was in response to an intensifying 94w. 
Chuuk has received over six inches of rain over the past day or so 
and will likely receive as much through the next 36 hours as 94w 
develops into a tropical depression and possibly a tropical storm 
later today. Convergent south winds into 94w will keep inclement 
weather conditions over the zones through midweek. Further 
west...Koror...near the monsoon trough axis will experience 
periods of scattered showers over the next several days...though 
Yap will remain far enough to the north to avoid most of the 
inclement weather. 


In response to increasing fetch length and winds associated with 
94w...ww3 suggests southerly swell will increase to the 8 to 10 foot 
range. This will necessitate the issuance of a high surf advisory 
for south exposures of the island by this afternoon or tonight. 


&& 


Gum watches/warnings/advisories... 
GU...none. 
Marianas waters...Small Craft Advisory until noon chst Monday for 
pmz151>154. 


&& 


$$ 


Middlebrooke/Lee 

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