507 
FXUS63 KOAX 100505
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
1105 PM CST Wed Dec 9 2020

...Updated Aviation Forecast Discussion...

.DISCUSSION...
Issued at 340 PM CST Wed Dec 9 2020

The main forecast problems are snow chances and amounts on Friday
evening into Saturday

In the short term, Upper ridging is forecast to break down as a weak 
upper short wave trough moves through the area on Thursday.  A cold 
front will move across the area early on Thursday.  No precipitation 
is forecast with passage of the front.  Winds will be strong, 
especially over northeastern Nebraska with gusts as 25-28 kts. 
Temperatures will be in the 40s across northeast Nebraska to mid 50s 
over southwest Iowa and southeast Nebraska.

On Friday, the pattern starts to set up for snow across southeast 
Nebraska and southwest Iowa. Cutoff low at this time off the 
southern California coast is expected to open up in response to a 
northern stream upper trough moving across the Pacific Northwest. 
Upper trough becomes progressive and moves across the central and 
southern Plains. By late Thursday night surface low develops in the 
Texas Panhandle and then lifts across Oklahoma into southern 
Missouri by late Friday night.  There is still uncertainty in the 
track of the storm which would affect the snow totals. Right now 
models are showing deformation band setting up across southern 
Nebraska and northern Kansas by Friday evening and then spreading 
across southeast Nebraska and western Iowa  as low lifts northeast 
and deepens.  Right now it looks like 2-3inches are possible with 
this event, mainly south of I-80. Up to an inch as far north as 
Norfolk, Wayne and Tekamah.

After this system passes through, the weather is forecast to remain 
tranquil with some weak shortwave troughs moving through a fast 
west-northwest flow. Although it is not noted in the forecast, 
there maybe some light precipitation possible on Tuesday.
 

&&

.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1102 PM CST Wed Dec 9 2020

VFR and light winds in the near term with some LLWS developing at
OFK by 09Z as 1000 ft AGL winds will be around 35 kts from the
southwest. A cold front shifts winds out of northwest between
12-16Z. MVFR ceilings may develop behind the front, but should
wait until late in the afternoon or evening hours.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.
&&

$$

DISCUSSION...Smith
AVIATION...Barjenbruch