087 
FXUS63 KOAX 301721
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
1221 PM CDT Sun Aug 30 2020

...Updated Aviation Forecast Discussion...

.DISCUSSION...
Issued at 420 AM CDT Sun Aug 30 2020

.SUMMARY:

Temps climb to near seasonal norms on Sunday with a chance of
strong to severe thunderstorms in the evening. Temps slip a bit
for the beginning of a new work week with another chance of
showers on Monday night / Tuesday morning. Dry weather fills out 
the remainder of early September. 

SUNDAY AND SUNDAY NIGHT:

As a surface high departs east, return flow brings more locations
into the 80s with mid-80s on the western file of counties in the
CWA by this afternoon. Tagging along with the warmer weather will
be a tongue of humidity from the surface up through mid-levels. 
This will be exacerbated by a LLJ setting up in eastern Nebraska 
in the evening. 

A strong summer cold front is evident in the northern Rockies 
this morning. It will sweep through the Dakotas and Nebraska over 
the course of the day. Timing for convection is best for central 
Nebraska as it will coincide with the day's hottest temps and the
area's greatest instability. Scattered strong to severe 
thunderstorms are possible along that front if they can overcome 
the robust cap. As noted in the previous discussion, ensemble 
guidance - this time 00Z HREF - continues to suggest a right turn
and subsequent southern deviation for the system's southern 
portion. This leaves most of the CWA dry. The HRRR has been 
fizzling the convection out on its approach. Have kept highest 
POPs well east of the Missouri River.

.LONG TERM:

Temps slip below normal as we begin a new week in the system's
wake. A trof passing to our south Monday night and tuesday may 
bring enough isentropic upglide for some showers over the southern
half of the CWA. Any moisture is welcomed over the region's dry
farmland. 

Temps briefly jump on Wednesday before another push of cooler and
drier continental polar air knocks numbers down again on Thursday.
Despite the cold front, the second half of the workweek should
remain dry. 

Worth noting: Beyond the 7 day forecast, general model consensus 
suggests the season's coolest temps so far with another 
reinforcing shot of cool Canadian air. 

&&

.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1220 PM CDT Sun Aug 30 2020

Winds will become gusty from the south this afternoon ahead of a
cold front approaching the region from the northwest. Outside of
some passing mid and high-level clouds, a few boundary-layer-
based clouds could form in the heat of the afternoon around FL040.
Isolated to widely scattered storms are expected to develop along
the front as it moves into the area this evening into the 
overnight hours, which we have currently addressed with PROB30 
groups. Winds will switch to northwest at 10-15 kt with gusts to 
20-25 kt with the passage of the front. SCT-BKN clouds in the 
FL040-060 range may also accompany the frontal passage.

&&

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

$$

DISCUSSION...Nicolaisen
AVIATION...Mead