Winter Storms Along With Possible Tornadoes

Major icing event forecast for northeast Oklahoma and southeast
KS/southwest MO into Monday morning..
Potential for a tornado outbreak in southeast Oklahoma and northwest
Arkansas Monday evening..
Friday's winter storm details looking a little better defined..

Latest radar showing virga developing around Stillwater to Tulsa. 12 km
NAM/WRF, 4 km WRF and GFS are showing a substantial area of drizzle and
freezing drizzle developing before sunrise across much of Oklahoma,
southeast of a Cheyenne to Medford line, and northwest of an Ardmore to
McAlester to Rogers, Arkansas line. Air is very dry at the surface and
it will take some time for air to soak up the moisture like a sponge.
This should be accomplished before sunrise though. I am still running
with the freezing drizzle north of a line from Granite to Chickasha to
Purcell to Seminole to Muskogee line, per previous forecast. WRF shows
some convective properties, with thunderstorm-freezing rain northeast of
Oklahoma City through the night. Any cells which get going will likely
lay down a significant track of freezing rain. But given widespread
freezing drizzle expected, problems may be be widespread regardless.

Latest WRF shows moisture east of a line from Ponca City to OKC to
Frederick by noon. I am expecting precip to impede warming. I'm quite
surprised to see new 0Z guidance with highs in the lower 50s for OKC.
At this time, I will leave the 47 high alone. Precip moves east to a
line from Joplin to Tulsa to just east of OKC to Ardmore by 6 p.m. 4 km
WRF hinting at severe convection developing in south-central OK north of
Ardmore by 5 p.m. Activity quickly lines out from east of Fayetteville
to north of Fort Smith to Ardmore. This is along a weak boundary I
think is created by moisture overrunning on top of the front. I think
the actual arctic front will remain across the river in north Texas
throughout the day. HPC guidance shows this well. Most of the CAPE
stays south of the arctic boundary but a small nose of 1700 j/kg noses
up into south central Oklahoma. I am more concerned about helicity.
New WRF shows 3 km helicity of 300 east of Dallas by 6 p.m. with
helicity increasing further northeast along the previously mentioned
boundary in southeast OK. Helicity goes nuts with numbers over 500
across the northern half of Arkansas. This could spell another night
time tornado event.

Overall, this scenario would call for no precip across most of our
viewing area after the the drizzle clears out during the afternoon. Our
southeast viewing area may be just close enough to the severe event to
be problematic.

Another weak front is seen charging down the lee of the rockies Monday
evening. I had a very hard time determining location of this front and
passage timing. Front essentially washes out and merges with the other
boundary to our south by Tuesday morning. I finally used a small dew
point pool I could see in the models and cloud cover from an accuweather
model as the reference for the boundary. It was depicted well in MOS
and should pass OKC around 6 p.m. Monday. This is 3 hours faster than
the previous run. The one thing it will do is kick the winds up.
Precip should be long gone so no worries about freezing roads on
Tuesday. Roads will be wind blown dry as per yesterday's forecast
discussion.

Tuesday looks to have highs in the upper 40s again per new 0z guidance
and previous forecast. Winds finally lay on Tuesday evening. There is
a significant discrepancy between GFS and ETA dew point guidance for
Wednesday morning. I will continue with the colder mid-20s forecast
after seeing the new runs.

Wednesday still looks windy and sunny with highs reaching the 60s. Fire
danger will be extreme and fire crews should plan ahead now for wildfire
management. A cold front moves in on Valentines day during the
afternoon and will bring strong northerly winds, so fire danger will
continue.

New 0Z GFS is still showing a significant winter storm on Friday. This
one appears to track slightly farther south than previous events. Low
should move from north of Abilene to Dallas to Shreveport. This would
place the southern half of the state in the favored area for heavy
snow. GFS shows snow beginning before sunrise on Friday and lasting
through sunrise Saturday. GFS has a bad track record of pinning down
exact heavy snow area so please take this next statement with a grain of
salt. Depending on which ratio you use, the new GFS dumps out between
11 and 16 inches of snow in Oklahoma City on Friday. The new GFS map is
not out yet so I don't have any other specifics. The QPF paints the
heaviest snow around McAlester.

Previous runs were dropping enough snow (3" plus) to make me follow NWS
and drop weekend temps significantly below MOS. Looks like we'll warm
up thourhg early next week. Publicly I'm going with a 1" accumulation
because I have seen some wild swings in these forecasts. For example,
some models have been taking this cutoff low elsewhere. If it were to
deviate paths significantly, we could end up with nothing.

There are more systems on the horizon. There appears to be a stormy one
which will mainly affect Arkansas on the 20th. Then perhaps another
winter storm around February 24th.

Thank you KFSM for the forecast coordination discussion.

Greg Whitworth/Fox 25 Weather-Used with permission.