Winter Storm in Oklahoma, February 2 to 3, 2022

Area Forecast Discussion...UPDATED
National Weather Service Shreveport LA
554 PM CST Wed Feb 2 2022

.AVIATION...
A cold front continues to sink S through Deep E TX/N LA this
evening, with IFR cigs having developed behind the front across
much of NE TX/SE OK/SW AR. Just ahead of the front, high based
MVFR/VFR cigs persist, but this will change this evening as cigs
quickly deteriorate to MVFR/IFR behind the front, as areas of RA
spreads ENE across much of the region. The RA will be widespread
across the area overnight through much of Thursday, which will
maintain IFR/LIFR cigs and reduced vsbys areawide. Meanwhile, the
cold post-frontal air will deepen enough such that the RA will
change over to FZRA across the Wrn sections of E TX and the Nrn
sections of SW AR after 12Z Thursday, affecting the TYR terminal
shortly thereafterwards. This transition to FZRA should eventually
affect ELD by 15Z, TXK by 18Z, and GGG/LFK between 20-22Z. The
precip. should remain liquid elsewhere across N LA, although a
brief transition over to -FZRA will be possible at SHV/MLU
by/after 00Z Friday. This precipitation should quickly diminish
during the evening, although IFR cigs will persist areawide
through Friday. NNE winds 6-12kts tonight, with occasional gusts
to 20kts over E TX, will become NNW 10-15kts after 12z. /15/

&&

.PREV DISCUSSION... /issued 404 PM CST Wed Feb 2 2022/

.SHORT TERM.../Tonight through Thursday Night/

At 22z, a cold front was located from south of Jacksonville TX,
to Marshall TX, to Camden AR. There is quite the gradient of temps
across the frontal boundary, as Tyler is sitting in the mid 40s
and Henderson is at 60 degrees F. The cold air damming by the
Ouachitas is quite evident as temperatures remain above freezing
in McCurtain County per local AWOS and Oklahoma Mesonet obs, while
Hugo is presently at freezing. However, conditions will
deteriorate from here.

A large area of precip is expected to rapidly develop across
Texas and spread eastward into the forecast area this evening as
strong large scale ascent increases ahead of an upper trough
digging through the Four Corners and Southern Rockies. The precip
should begin as rain across the entire forecast area, and a few
isolated thunderstorms cannot be ruled out south of Interstate 20.
Latest indications are now that temperatures will fall below
freezing this evening before midnight in McCurtain County
resulting in the precip transitioning to freezing rain. This is
earlier than previous forecasts, so the onset time of the Winter
Storm Warning was moved ahead to 03z this evening for Southeast
Oklahoma.

The freezing rain will very slowly expand southeastward into
portions of Southwest Arkansas and Northeast Texas after midnight
and during the early morning hours of Thursday. There has been an
increasing concern of some of the Arctic air back-dooring into
South Central Arkansas from the northeast. Combined with the heavy
precipitation rates expected, this could easily result in moderate
to heavy freezing rain by mid to late morning. Therefore, Union
and Columbia Counties were added to the warning. Many of the
latest high-resolution models are much more aggressive with the
cold air penetrating into East Texas and Southern Arkansas. This
includes the potential for ice accumulations up to one tenth of an
inch in Cherokee County, so they were added to the Winter Storm
Warning, also. In addition, Angelina and Nacogdoches Counties were
added to the advisory due to an increased potential for at least
trace ice accumulations.

The precip types will continue to get rather complicated through
the event. As the freezing rain line advances south and east,
locations farther to west should see the addition of sleet to the
freezing rain as the atmosphere continues to cool, followed by a
change to predominantly snow and sleet. Locations northwest of a
line from Clarksville TX to De Queen AR should eventually see the
precip change over to all snow by mid to late Thursday afternoon.

Latest indications are that most of Louisiana should continue to
see liquid rain until Thursday afternoon when a mix of rain and
freezing rain will begin to gradually move southward into the
area. The precip should decrease in coverage and intensity
significantly by late Thursday afternoon. However, model guidance
suggests we will remain in a favorable region for lift in the
right entrance region of a 500 hPa jet streak. This will likely
allow some light freezing rain and sleet to linger across much of
Louisiana into at least the early evening hours, but any remaining
precip should be very light. There may also be some additional
light snow in McCurtain County as the upper trough axis
approaches. Depending on how this unfolds, the winter weather
headlines may need to be extended in time into Thursday evening,
but this is still uncertain.

Total freezing rain accumulations of one tenth to a quarter of an
inch are expected across much of the Winter Storm Warning area.
The highest amounts, which could be upwards of one half inch of
ice, should be confined to northern sections of McCurtain County.
Locations farther south in the Winter Weather Advisory will see
between a few hundredths of an inch up to one tenth of an inch.
However, most locations will likely see at least a trace of ice
before the event is over.

Total snow/sleet accumulations may be as high as an inch northwest
of a line from Mount Vernon TX to De Queen AR, with much lower
amounts to the southeast.

CN

&&

.LONG TERM.../Friday through Wednesday/

The long term period of our forecast is looking very cold to start
with a moderation back to average by the middle of next week. An
Arctic air mass of 1040mb will be situated over N TX early Friday
with our air temps in the upper teens far north to upper 20s far
south. Most of us will be in the low to mid 20s with most if not all
of the accumulated ice still well in place. Bridges and overpasses
will have a chance to melt off some with upper 30s and lower 40s for
highs on Friday afternoon. Sunshine would really help, but our skies
will be clearing during the late day and evening, which will then
make for an even colder start to the weekend. Mid teens far north
and low to mid 20s elsewhere will have any issues that remain frozen
rock solid.

The air mass will begin to edge eastward on Friday, but only settle
into the I-30 corridor at 1038mb for the overnight. Meanwhile aloft,
the GFS has a closed upper low of 561dam, thankfully starved of
moisture to precipitate, or perhaps even make clouds which would
hamper warming. The ECMWF had a quicker trough also dry. The N/NE
surface winds of 5 to 10 mph will add a chill to the air temps with
a range of 40s expected for afternoon highs to really be the big
melt day.

Skies look to be clear for Saturday night with more teen and low 20s
with the core of the air mass overhead and good radiational cooling
with L/V or even calm wind. Just as we loose this huge Arctic air
mass to the east of the MS River, a fresh 1035mb high will follow in
it's predecessors footsteps. So lows keep steady well below average
and then finally get above freezing by mid to late week. Highs will
do much better, getting back to average by midweek under sunshine
and more high pressure. /24/

&&

.PRELIMINARY POINT TEMPS/POPS...
SHV  36  40  28  40 / 100  90  20  10
MLU  38  44  27  40 /  90 100  30  10
DEQ  28  33  20  39 / 100  90  10   0
TXK  33  36  26  38 / 100  90  10   0
ELD  30  35  24  37 / 100  90  20  10
TYR  30  34  22  35 / 100  90  10   0
GGG  35  39  25  38 / 100  90  10   0
LFK  39  43  26  41 / 100  90  20   0

&&

.SHV WATCHES/WARNINGS/ADVISORIES...
AR...Winter Weather Advisory from midnight tonight to 6 PM CST
     Thursday for ARZ059-070-071.

     Winter Storm Warning from midnight tonight to 6 PM CST Thursday
     for ARZ050-051-060-061-072-073.

LA...Winter Weather Advisory from midnight tonight to 6 PM CST
     Thursday for LAZ001>004-006.

OK...Winter Storm Warning from 9 PM this evening to 6 PM CST Thursday
     for OKZ077.

TX...Winter Weather Advisory from midnight tonight to 6 PM CST
     Thursday for TXZ097-111-112-126-137-138-150-152-165.

     Winter Storm Warning from midnight tonight to 6 PM CST Thursday
     for TXZ096-108>110-124-125-136-149.

&&

15

Hazardous Weather Outlook...UPDATED
National Weather Service Shreveport LA
1242 PM CST Wed Feb 2 2022

ARZ059-070>073-LAZ001>006-010>014-017>022-TXZ097-111-112-126-137-
138-149>153-165>167-031845-
Little River-Miller-Lafayette-Columbia-Union-Caddo-Bossier-
Webster-Claiborne-Lincoln-De Soto-Red River-Bienville-Jackson-
Ouachita-Sabine-Natchitoches-Winn-Grant-Caldwell-La Salle-Bowie-
Morris-Cass-Marion-Gregg-Harrison-Cherokee-Rusk-Panola-
Nacogdoches-Shelby-Angelina-San Augustine-
1242 PM CST Wed Feb 2 2022

This Hazardous Weather Outlook is for southern Arkansas, for
northern Louisiana, and for northeast and deep east Texas.

.DAY ONE...This Afternoon and Tonight...

Showers and isolated thunderstorms will be increasing in coverage
this afternoon and evening. The cold front will continue moving into
the area overnight with showers becoming a steady light to
moderate rain during the overnight. This Arctic cold air is very
shallow, so as the air temperature eventually gets down to
freezing, this rainfall will begin to stick. The Winter Weather
Advisory begins at midnight with bridges and overpasses becoming
hazardous first. As the subfreezing air continues to arrive,
accumulations of ice are going to occur generally well north of
I-20. Expect driving conditions to quickly deteriorate once this
transition occurs.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday...

A cold rain will greet the day for most locales, but the wintry
precipitation of freezing rain and sleet will continue to expand
south and eastward throughout the day on Thursday, affecting
bridges and overpasses initially. Some accumulation of ice up to
one tenth of an inch will continue to make elevated surfaces
extremely hazardous with some roads becoming hazardous as the
afternoon wears into the evening. Some light snow accumulations
may mix in as time goes on, but may become more likely at the tail
end of the event with deeper cold air. Given already wet
surfaces, roads may thaw and refreeze with highs in the 40s and
lows in the 20s. This will continue making driving hazardous
potentially through Friday and perhaps Saturday. The weekend will
see a slow and dry warming trend last into next week.

.SPOTTER INFORMATION STATEMENT...

Activation of emergency management personnel, amateur radio
operators and storm spotters may be needed through tonight.

ARZ050-051-060-061-OKZ077-TXZ096-108>110-124-125-136-031845-
Sevier-Howard-Hempstead-Nevada-McCurtain-Red River-Franklin-Titus-
Camp-Wood-Upshur-Smith-
1242 PM CST Wed Feb 2 2022

This Hazardous Weather Outlook is for portions of southwest
Arkansas and northeast Texas and for southeast Oklahoma.

.DAY ONE...This Afternoon and Tonight...

The cold front is moving into the area this afternoon. Much colder
air will move into the area tonight with showers becoming a steady
light to moderate rainfall during the overnight. This Arctic cold
air is very shallow, so as the air temperature eventually gets
down to freezing, this rainfall will begin to stick this evening
with bridges and overpasses becoming hazardous first. Eventually
some roads may become hazardous as well. Expect driving conditions
to quickly deteriorate once this transition occurs.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday...

Wintry precipitation will continue to mix from freezing rain to
sleet and snow as the cold air deepens while expanding eastward
throughout the day on Thursday. Ice accumulations of one tenth, up
to one quarter of an inch, will make travel extremely hazardous.
Given already wet surfaces, roads will thaw and refreeze on Friday
and perhaps into the weekend. The weekend will see a slow and dry
warming trend last into next week.

.SPOTTER INFORMATION STATEMENT...

Activation of emergency management personnel, amateur radio
operators and storm spotters will be needed through tonight.

24