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000 
FXUS64 KOUN 112344
AFDOUN

Area Forecast Discussion
National Weather Service Norman OK
544 PM CST Wed Dec 11 2019

.AVIATION...
1200/1224 TAFs...
 
High clouds will continue to increase, as a shortwave trough
approaches the southern Plains from the west tonight.  Modest
moisture advection may result in areas of MVFR ceilings later 
this evening and overnight, mainly in and near WWR and CSM. Low 
level winds will also become rather strong after 4-5Z which will 
result in LLWS, especially around OKC/OUN/PNC. High clouds should 
decrease some Thursday with a south to southwest wind. 


&&

.PREV DISCUSSION... /issued 354 PM CST Wed Dec 11 2019/ 

DISCUSSION...
For tonight, cloudiness will be increasing as a short wave trough
passes through, with its associated surface low/boundary staying 
well north of our area in the Central Plains. The cloudcover along
with increasing south winds keep nighttime temperatures a little 
bit warmer than last night. Will go with Superblend model for 
tonights temperature and it should also be breezy mainly across 
our northwest. Still expecting slightly warmer than normal 
temperatures in the short range of the forecast, with little 
change to the previous forecast values. 

Another short wave will be digging across the Central Plains on 
Friday night, which will push a dry cold front into the Southern 
Plains.  With more Pacific based air initially coming in, we should 
not see a drastic temperature change behind the front for 
Saturday. However, a much deeper trough behind this system will 
start bringing in much colder Canadian based air beginning 
Saturday night into early next week. This next deeper system will 
also introduce low POPs of light snow across northern Oklahoma for
Saturday night. Our POPs increase further southward on Sunday 
with light rain across the remainder of our area during the day. 
Increasing Gulf moisture across eastern Texas advecting into 
southeast Oklahoma may result in marginal instability for 
convection to develop, and is also supported by negative Lifted 
Index values. As a result, isolated thunderstorms have been 
introduce into the grids across southeast Oklahoma for Sunday. 
However, POPS are being kept low at this point since both GFS and 
the ECMWF remain in disagreement at least through Sunday night. 
The European model is consistently the wetter of the two medium 
range models, where the GFS runs stay dry in our area with QPF 
across the eastern half of Oklahoma for Sunday night. If the ECMWF
solution is correct for Sunday night, then rain could change over
to light snow across much of our forecast area. For now, any snow
accumulations would be across far northern Oklahoma. The exact 
precipitation types may change as we get closer to the event.

For Monday, a changeover to light rain as the system exits off to 
our east with a very subtle warming trend beginning.

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  36  54  35  58 /   0   0   0   0 
Hobart OK         35  55  32  61 /   0   0   0   0 
Wichita Falls TX  34  57  36  61 /   0   0   0   0 
Gage OK           39  57  30  61 /   0   0   0   0 
Ponca City OK     38  55  34  57 /   0   0   0   0 
Durant OK         33  55  36  58 /   0   0   0   0 

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...None.

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