Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS63 KOAX 201715

Area Forecast Discussion
National Weather Service Omaha/Valley NE
1115 AM CST Wed Feb 20 2019

.SHORT TERM...(Today through Friday)
Issued at 346 AM CST Wed Feb 20 2019

Snowfall amounts continue to be on the lighter side of our
forecast ranges but we had quite an intense band moved quickly
through the area around 10pm-1am, dropping over 1.5"/hr rates. As
the dry slot continues to move northeast with the system this
morning, light freezing drizzle has been reported across the
region where radar returns are fairly light. This has produced a
light glaze of ice early this morning but we should transition
back over to snow as the layer saturates a bit deeper while the
slightly negatively tilted trough continues to push northeast
across the Central Plains. This could add an additional inch or
two of snow yet through this morning and near-term model
indications show that the light snow should continue to fill in a
bit through sunrise. We will be able to walk the winter storm
warning out of the region from southwest to northeast later this
morning as the snowfall continues to diminish throughout the
morning. A weak ridge of surface high pressure will build over the
area today and model trends show clouds scattering out as the
system pushes northeast.

.LONG TERM...(Friday night through Tuesday)
Issued at 346 AM CST Wed Feb 20 2019

Southwesterly flow aloft will persist across the region Thursday as
a strong closed low drifts east across the Great Basin, eventually
ejecting into the Southern Plains early this weekend. Meanwhile,
northern stream energy will dig across the High Plains region during
this time period. Ahead of this system, increasing low- level
moisture will stream north with a much warmer airmass spreading
north off the Gulf and into the area. Strengthening isentropic
upglide could start the onset of precipitation as early Thursday
evening while a few lead shortwaves eject northeast out of the
main low. Rain in our south, snow in our north, with a mixed bag
in the middle is what we currently have forecast. Most of the
icing looks to occur south of I-80 with predominantly snow in our
northwestern third of the CWA through Saturday afternoon at least.
As the tightly wound upper low moves northeast and rapidly deepens across
eastern Kansas and northern Missouri on Saturday night, our
entire forecast area will be situated under a strong deformation
zone with much colder air on the back side of the system. In
addition to a very tight surface gradient, 850mb forecast winds
are around 45kts off the ECMWF to an impressive 60kts off the GFS
which could create blizzard conditions if everything comes
together. Certainly blowing and drifting snow will be an issue
Saturday night in addition to the potential for heavy falling
snow. Our forecast snowfall totals only extend out through 00z
Sunday which up through then gives about 0.0 in our far southeast
as we remain primarily rain to near 4-6" in our far northwest.
Again, these are totals only through 00z Sunday with additional
snow after that which could amount to very heavy snowfall by the
time it is all said and done. What exactly moderate rainfall
amounts of near an inch in our southeast do on top of frozen
ground and snow cover to our rivers is still quite uncertain but
certainly something to consider. This is a system to really keep a
close eye on as we move closer to the weekend.


.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1109 AM CST Wed Feb 20 2019

Light snow and associated lower visibilities will continue to
move out of the area early this afternoon. Conditions are expected
to improve to VFR at KOMA within the next hour or two. Skies will
remain VFR through the remainder of the TAF period at all sites.
westerly winds will become light and variable by 12Z Thursday
morning, before veering to the east late in the period.


NE...Winter Storm Warning until noon CST today for NEZ012-015-018-034.

IA...Winter Storm Warning until noon CST today for IAZ043-055-056.



AVIATION...KG is the U.S. government's official web portal to all federal, state and local government web resources and services.