Heavy Snow and Winter Weather in Texas, February 4 to 5, 2020

Area Forecast Discussion
National Weather Service Lubbock TX
529 AM CST Tue Feb 4 2020

.AVIATION...
Low CIGs have moved into the region following the passage of a
strong cold front. CIGs will move between the IFR/MVFR categorical
threshold throughout much of the day. Isolated light rain and snow
showers will be possible at the KLBB and KPVW terminals during
the late morning and early afternoon hours, with a gradual
increase in coverage of precipitation with light snow expected
towards 00Z. CIGs may fall into LIFR during the overnight hours in
addition to the potential for reduced visibilities and widespread
snow. At least MVFR/IFR conditions prevail across all terminals
for this TAF period.

Sincavage

&&

.PREV DISCUSSION... /issued 307 AM CST Tue Feb 4 2020/

DISCUSSION...
Very minor changes were made to the upcoming winter weather forecast
mainly concerning location and amount of snowfall. Operational runs
of the snowfall forecast have come down to a more reasonable level
more in line with what our forecast has been the past 24-48 hours.
There will likely be a very sharp snowfall gradient somewhere in the
northern third of the FA.

The upper level trough was slowly churning across the Intermountain
West and appears to already have a closed off height contour over
Colorado. A broad area of upper level divergence has presently moved
overhead. This will continue through Wednesday afternoon to a
varying degree on the downstream side of the upper trough. The upper
level divergence will be punctuated by stronger bouts as small jet
maxes move through the upper flow. The strongest still looks to be
within the 06Z to 12Z time frame early on Wednesday morning. All of
this upper level support is also indicated in the Q-vector fields.
Downward motion does not spread overhead until late in the afternoon
on Wednesday. The heaviest snow will be where the mid level
frontogenetical forcing sets up since good upper level support will
exist through the event. The orientation and location of the
frontogenesis has not changed much from previous model runs. It will
most likely extend from the northern Permian Basin northeastward
into southwest Oklahoma. This frontogenetical layer looks to be
maximized from 750-650mb with an area of negative EPV above which
also suggests a heavy snow potential. CIPS analogs also highlight
this area from the Permian Basin through southwest Oklahoma as
having the best chances of heaviest snowfall. Cross sections of
theta-e show mostly weak symmetric stability with some potential for
CSI in the Rolling Plains and southeastern South Plains. Otherwise,
there is not much potential for upright convection with the
convective instability residing over the Big Country. Any
thundersnow would have to come from the frontogenetical forcing and
negative EPV combining with the large scale lift at the right
moments.

Before the main snow event occurs tonight, a cold front was
currently moving through the area much quicker than anticipated.
Light precipitation is still expected this afternoon spreading in
from the west. With colder temperatures already here, a rain/snow
mix will likely be confined to the southwestern South Plains with
snow elsewhere. A quick end to the event will occur late Wednesday
afternoon with the trough axis moving overhead. Very cold
temperatures will then take over Thursday morning with wind chills
around 0F. Warming will occur through the weekend with a brief break
on Saturday as a cold front moves through Friday night.

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning from noon today to 6 PM CST Wednesday for
TXZ026-030>044.

Winter Weather Advisory from noon today to 6 PM CST Wednesday
for TXZ021>025-027>029.

&&

09/01

Hazardous Weather Outlook
National Weather Service Lubbock TX
407 AM CST Tue Feb 4 2020

TXZ021>044-051015-
Parmer-Castro-Swisher-Briscoe-Hall-Childress-Bailey-Lamb-Hale-Floyd-
Motley-Cottle-Cochran-Hockley-Lubbock-Crosby-Dickens-King-Yoakum-
Terry-Lynn-Garza-Kent-Stonewall-
407 AM CST Tue Feb 4 2020

This Hazardous Weather Outlook is for the South Plains, Rolling
Plains and the far Southern Texas Panhandle.

.DAY ONE...Today and tonight.

A winter storm warning has been issued for the Rolling Plains and
much of the South Plains from this afternoon through Wednesday
afternoon. Snow accumulations up to 8 inches will be possible across
the Rolling Plains and up to 5 inches in the South Plains. A winter
weather advisory is in effect for the extreme southern Texas
Panhandle where up to 2 inches of snow can be expected.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

A winter storm warning and advisory will remain in effect through
late Wednesday afternoon. Wind chills between 0 and 5 below will be
possible Thursday morning across the entire region.