Weather

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fxus63 kind 131054 
afdind 


Area forecast discussion 
National Weather Service Indianapolis in 
654 am EDT Monday Oct 13 2008 


Aviation...discussion for 12z tafs 


Low level moisture will increase from west to east during the day as high 
pressure shifts east. Ceilings look to be around bkn050-060 perhaps 
before 18z at laf/huf. Moisture looks to hang around through the 
remainder of the taf period...but there should be periods where lower layers 
scatter out as drier air tries to work back in. Did not get too 
detailed in tafs with timing of breaks uncertain. Winds will 
increase to 10kt with possible gusts near 15kt by afternoon...but should 
diminish some after sunset. 


&& 


Discussion... 
main concerns for the short term are temperatures today and chances 
of rain on Tuesday. Yesterday the GFS was the better model for maximum 
temperature but stil about 1 degree to warm. The NGM maximum temperatures have been 
running very low for the last several days. It continues to be the 
lowest for today. There will be an abundance of sunshine during the 
morning. This will allow temperatures to quickly increase. 850 mb temperatures don't 
change much during the day. Clouds will be increasing this afternoon 
which will slow temperature increase. The GFS temperatures which are a few degrees 
cooler then yesterday look the best. Cloud cover will continue to 
increase tonight. The GFS and Eta model temperatures differ very little and are a 
little warmer then the NGM. With the cloud cover slowing temperature fall 
will go with the GFS/Eta model temperatures. On Tuesday a cold front will be 
moving through Indiana. The GFS is the quicker of the three. The 
models only have limited moisture with this system so will go with 
low probability of precipitation. Anything that does develop will not occur until afternoon 
instability. Will go with current forecast and keep chance off until 
afternoon the front will then become stationary over central 
Indiana. More moist air will move into Indiana so will increase the 
probability of precipitation Tuesday night and Wednesday. 


In the extended...the operational GFS rapidly ends any precipitation 
Wednesday night. This is much faster than the European which keeps 
precipitation in on Thursday. Will go with model blend but closer to 
faster NAM/GFS. 


GFS brings an upper level disturbance moving southeast into the Ohio 
Valley Friday. It actually gives US some quantitative precipitation forecast. Will mention a little 
more clouds then...but will keep US dry for now. 


Saturday looks fair and cool as high pressure builds across our 
region and Sunday will be a little warmer as the upper trough 
continues eastward. 


&& 


Ind watches/warnings/advisories...none. 


&& 


$$ 


Aviation...cs 
public...sh