I like reading the NWS Forecast Discussion for more detailed info:
Area Forecast Discussion
National Weather Service Omaha/Valley NE
544 PM CST Tue Dec 14 2021
...Updated for 00Z Aviation Forecast Discussion...
.DISCUSSION...
Issued at 353 PM CST Tue Dec 14 2021
...HIGH IMPACT WEATHER DAY EXPECTED WEDNESDAY...
The stage is set for a rare, potentially high impact weather day
for Wednesday, not that dissimilar from Christmas Day 2016. We
are expecting a high wind event to affect the forecast area
Wednesday afternoon and evening with widespread wind gusts 60 mph
or higher, and possibly even up to 70 mph not out of the question.
A high wind
warning remains in effect for our entire coverage
area from 9 am through 9 pm. That may be about 3 hours too soon
for the onset as the stronger
surge of severe level winds won`t
be moving in from the southwest until after 12 pm, but offices
collectively agreed to leave the timing in place to avoid
confusion. The most damaging period of winds is probably about
3 pm and beyond where we see the wind gusts increase above
60 mph, based on HREF timing of just the
mean ensemble gust.
Looking the HREF
ensemble max would suggest
hurricane force winds
are possible for a several hour period as a worst case scenario.
We have significantly ramped up our messaging efforts today.
There will be damage to trees and powerlines, and possibly to some
structures as well. There will be
power outages. There is also
concern that the strong winds could kick up dust in open areas and
near construction zones. Now is the time to make preparations for
possible damage tomorrow.
The secondary weather concern Wednesday is whether a line of
thunderstorms develop and the potential severity of those storms.
The morning will
likely remain dry. But CAMs suggest that
scattered showers could develop by Noon and quickly move to the
east. And then an extreme dry line punching in the from the west
could trigger a line of thunderstorms that race eastward at 60 mph
or faster, but
likely east of the area by 5-6 pm. It`s this line
of storms, if it develops, that could trigger enhanced areas of
wind gusts 70 to 75 mph, or possibly higher. We`ll also have to
monitor for weak tornadoes embedded within the line, primarily
along/east of the Missouri River, as
SPC increased the
probability to 5% with their late morning update.
Helicity tracks
from the HREF would suggest the greater threat could be
north/northeast from Omaha.
The advancing dryline will also trigger an extreme fire event,
with some models mixing dewpoints down sufficiently enough to
lower
humidity to 15 to 25 percent. Important to note that models
are handling this dry punch very differently, so that remains a
challenge. This combination of very dry air and wind gusts of
60+ mph will create extreme fire danger, and a red flag
warning
has been issued for areas along/south of I80. This is also
generally the same area that did not see substantial or any
snowfall with the weather system last Friday. Any
power lines that
get blown down could also arc and ignite fires, and given the
ambient conditions, those fires would be extremely hard to
contain. If fires do develop, winds will be shifting from the
south to the southwest to west through time.
And finally, on the back side wraparound portion of this system,
there
likely will be showers that quickly change to snow in
northeast Nebraska, coincident with 60+ wind gusts. And while the
snow amounts would only be 1/2" or less northwest of a line from
Albion to Norfolk to Wayne in northeast Nebraska, areas of
blowing
snow with near whiteout conditions couldn`t be ruled out. Or
perhaps even a snow-
squall type of event. Nevermind that wet roads
could
freeze quickly with temperatures quickly dropping into the
upper 20s creating slick roads.
Regarding warm temperatures, we are currently running just a
couple of degrees short of record highs today in Lincoln and
Omaha. And still on track to break high temperatures at all three
of our primary
climate locations on Wednesday. And while it will
be very mild tonight, breaking records for warm morning lows,
temperatures by midnight will have cooled enough to un-break those
records.
The weather through the remainder of the forecast is quiet with
highs in the 40s Thur/Fri. A strong
front drops us into the 30s
for highs on Saturday, but it should remain dry. 40s mostly again
for Sunday, back to the 30s for Monday, and back to the 40s for
Tuesday.