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fxus61 Kiln 231747 
afdiln 


Area forecast discussion 
National Weather Service Wilmington Ohio 
1247 PM EST Monday Nov 23 2009 


Synopsis... 
upper level disturbances will move northeast across the region 
today into this evening. A cold front will approach from the west 
Tuesday night and cross the area on Wednesday. An upper level low 
will bring unsettled weather for the latter part of the week. 


&& 


Near term /until 6 PM this evening/... 
very light rain showers over much of County Warning Area will continue to move 
north this morning and afternoon. The 60 probability of precipitation running in central 
Ohio were left untouched with a large area of light rain in the 
Portsmouth area that will continue its northerly trek today. Any 
rainfall will be just about enough to wet the ground at its worst. 
Cloudy skies will help keep temperatures down today but there should 
still be some increase as the day GOES on. In all...very little 
changes were made to the forecast for the morning update. 


&& 


Short term /6 PM this evening through Wednesday/... 
light rain may still be lingering in central Ohio in the evening 
before ending. Region will then be in between systems with light 
winds and abundant low level moisture. Appears that some 
visibility restrictions could develop late tonight into Tuesday 
morning. So inserted patchy fog. Next chance of precipitation 
should come during the latter half of Tuesday night into Wednesday 
when a weak cold front approaches and then crosses the area. NAM 
appears to be too slow with this system. But other available 
models were in relatively good agreement bringing the front 
through on Wednesday. After frontal passage there will be some 
gusty west southwest winds. Temperature forecast did not stray too 
far from guidance consensus. 


&& 


Long term /Wednesday night through Sunday/... 
models in general agreement bringing a potent system that will 
turn into a closed low across the region on Thursday and Friday. 
This should bring a good chance of rain on Thanksgiving with the 
chance of showers continuing through Friday before diminishing 
Friday night when the system departs off to the east. Cold air 
associated with this upper low will result in thermal profiles 
becoming favorable for some snow showers from Thursday night 
onwards until precipitation comes to an end. Ridging at the 
surface and aloft will build in over the weekend bringing dry 
conditions and allowing temperatures to rebound closer to normal 
for this time of year. 


&& 


Aviation /18z Monday through Saturday/... 
pseudo warm front a few thousand feet up appears to be crossing 
County Warning Area to the north this early afternoon. Scattered very light 
rainfall is all over the radar scope at this moment in time as 
well...but should remain light and not affect visibilities this afternoon 
or early evening. Some lower ceilings will pull into the region from 
the south as the front moves north. Winds will turn more southerly 
this evening and help pull low level moisture from the deeper pool 
noted to the south and southeast. 


Deep low level moisture will persist over the Ohio Valley for a 
while...though some breaks may occur briefly at almost any 
location. As the column moistens up...ceilings are expected to 
lower bit by bit and visibilities overnight will probably also suffer 
from this increased boundary layer moisture. Some improvement in 
ceilings/visibilities is expected as some mixing occurs early tomorrow 
morning. 


Outlook...MVFR ceilings/visbys possible Wednesday into Friday. 


&& 


Iln watches/warnings/advisories... 
Ohio...none. 
Kentucky...none. 
In...none. 


&& 


$$ 
Synopsis... 
near term...franks 
short term... 
long term... 
aviation...franks