643 
FXUS63 KOAX 312109
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
309 PM CST Mon Dec 31 2018

.SHORT TERM...(Tonight through Thursday)
Issued at 309 PM CST Mon Dec 31 2018

Early afternoon water vapor imagery revealed a dynamic large-scale
pattern, featuring a shortwave trough ejecting northeast through
the mid MS Valley ahead of a prominent mid to upper-level low over
UT. In the low levels, an arctic front progressed through our 
area this morning with very strong northwest winds ushering a 
bitter-cold air mass into the mid MO Valley this afternoon.

The heaviest and most persistent precipitation associated with 
the deformation axis of the mid MS Valley disturbance has 
edged to the east of our area as of early afternoon. However, 
modest frontogenetic forcing in the 925-850-mb layer is yielding 
patches of light snow across portions of southern SD and northern 
NE. And latest short-term model guidance suggests that periods of 
light snow or flurries could linger through this evening across 
portions of northeast NE into west-central IA. Owing to the light 
precipitation and strong winds, NDOT data and traffic cameras 
indicate poor travel conditions across parts of northeast NE. As 
such, we have issued a winter weather advisory until 6 PM. 
Elsewhere, some light drizzle will remain possible over parts of 
southwest IA early this evening.

Winds will likely remain strong through this evening before 
diminishing late tonight into Tuesday morning. The winds coupled 
with the influx of arctic air is resulting in wind chill readings 
of -10 along and north of a Wayne to Albion line as of 3 PM. 
Those values will continue to fall to -20 to -25 overnight and a 
wind chill advisory is in effect from 6 PM until noon on Tuesday.
Low temperatures tonight will range from -5 to -7 near the SD 
border to 10 above over far southeast NE and southwest IA.

Surface high pressure will build into the region on Tuesday with 
a decrease in clouds. High temperatures will be cold, ranging from
around 5 above in the far north to around 15 in the south.
Decreasing surface winds owing to the proximity of the surface
high will mitigate the potential for very cold wind chills with
afternoon readings of negative single digits north and near zero
to slightly above zero south.

By Wednesday into Thursday, a strong synoptic cyclone will
traverse the southern U.S. with moderating temperatures to the
north of it's track, over the mid MO Valley. Highs on Wednesday 
will be in the upper 20s to lower 30s with mid 30s to around 40 on
Thursday.
 
.LONG TERM...(Thursday night through Monday)
Issued at 309 PM CST Mon Dec 31 2018

Consensus of latest medium-range guidance suggests that we will
remain in a dry and mild weather pattern through the weekend and
at least early next week.

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1115 AM CST Mon Dec 31 2018

A strong cold front will continue to make its way through the
region. Ceilings will remain MVFR with patches of IFR through the
overnight hours. Light snow will be possible at KOFK, with a
chance of light snow and freezing drizzle at KOMA. Only minor snow
accumulations are expected. Up to an inch will be possible at KOFK
and under 0.5" is anticipated at KOMA. Little to no precip is
expected to reach KLNK at this time. Precipitation will move out
of the area late this evening. However, northwest winds will gust
from 25-38kts through the rest of today and into tonight, 
eventually diminishing around 12Z Tuesday morning.


&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...Wind Chill Advisory from 6 PM this evening to noon CST Tuesday 
     for NEZ011-012-015>018-030>033-042-043.

     Winter Weather Advisory until 6 PM CST this evening for NEZ011-
     012-017-018-031-032.

IA...None.
&&

$$

SHORT TERM...Mead
LONG TERM...Mead
AVIATION...KG