Winter Storm and Winter Weather in Texas, January 1, 2021

Area Forecast Discussion
National Weather Service Lubbock TX
1051 PM CST Thu Dec 31 2020

.AVIATION...
Mostly light snow at KLBB expected for several more hours with
MVFR as deformation axis continues from near the Lubbock area
through Childress. Also we have continued a mention for Wind
Shear at KLBB where the Doppler RADAR indicates strong northerly
flow within 700 feet of the ground. Childress has a much more
moist environment and more likely for significant snow and sleet
through the remainder of the night before tapering around
daybreak. KPVW appears will remain near or just on the dry side of
this event. VFR should dominate all areas during the day Friday
with lingering modest northerly flow. RMcQueen

&&

.UPDATE...
Deformation zone snow bands continue to develop and rotate through
the Rolling Plains into the central and southern South Plains.
Light snow has developed as far west as Lubbock with at least
light accumulations starting as well. Heavier accumulations have
occurred, such as 6 inches or more in the Post area. We have
updated the Winter Weather Advisory to include all of Lubbock
County and for local accumulations as high as 6 to 8 inches.
Solutions linger the deformation axis into early Friday before
edging east or northeast away from the area. RMcQueen

&&

.PREV DISCUSSION... /issued 710 PM CST Thu Dec 31 2020/

UPDATE...
The major winter storm was over central Texas and spreading snow
further west to along and even west of US 87 in Lynn County south
of Lubbock, and through Slaton and Ransom Canyon just east of
Lubbock in Lubbock County. We have added both Lynn and eastern
Lubbock Counties to the Winter Weather Advisory. But the situation
remains highly dynamic and fluid this evening. RADAR was showing
reflectivity developing over the western South Plains that may
indicate the back edge of the Deformation Axis. Latest HRRR
indicates a spoke of reflectivity also rotating back west to very
near Lubbock by mid evening. But we still have a dewpoint
depression of over 20 degrees needing to be mostly overcome in
order for snow rates to have a significant impact. None-the-less,
this is a very close call for the more populated I-27 corridor
from Lubbock through Plainview this evening into early Friday and
we will update as needed. RMcQueen

PREV DISCUSSION... /issued 610 PM CST Thu Dec 31 2020/

AVIATION...
A major winter storm system was rotating northeast over central
Texas. Snow and sleet bands were spreading north through the
Rolling Plains and eastern South Plains and best estimate is they
will remain just to the east of both KLBB and KPVW. Precipitation
has lifted north to near KCDS and will lead to increasing snow
through the evening. Appears the best chance for LIFR conditions
at KCDS will occur late this evening into early Friday morning
once full moistening and cooling occurs at the surface. Snow
chances at KCDS are expected to diminish near daybreak Friday with
gradual improving in ceiling thereafter. Cool northerly flow will
continue over KLBB and KPVW with VFR expected to dominate, even
with a possibility of light snow this evening. RMcQueen

PREV DISCUSSION... /issued 224 PM CST Thu Dec 31 2020/

SHORT TERM...
The afternoon short term forecast continues to revolve around the
snow potential this evening into the first day of 2021. While some
uncertainties still remain, the potential for accumulating
snowfall across the eastern half of the forecast area seems
likely with the greatest confidence in accumulating snowfall
across the last two columns of the Rolling Plains where the better
moisture and forcing will reside.

That being said, late afternoon observations show a moistening of
the lower atmosphere from Lubbock southeastward with snow being
reported at Lake Alan Henry and a few flurries across the City of
Lubbock. This activity is tied to energy moving northward into the
FA from the south. CAMs continue to show the upper low tracking
northeastward, digging and reforming a new deformation zone over
Oklahoma after sunset shifting the precipitation shield more to the
east putting areas from Garza County northward to Briscoe County on
the fringe of the snowfall by late this evening.

This biggest uncertainty continues to be the dry air near the
surface and in the mid-layers and how it will affect our
accumulations due to sublimation as top down moistening occurs. Have
trimmed snowfall amounts and QPFs back a tad to take this into
account, but the winter weather advisory still stands.  It does
appear from AMA and MAF 12Z soundings and from 12Z NAM that the
colder solution for mid-level temperatures will win out with snow
the dominant, if not sole, precipitation phase for the event.

LONG TERM...
The long term portion is quiet relative the storm in the short
term. Another, albeit weaker, upper level low will track across
the region Friday night. This one will also be much more limited
in the moisture it can tap. Add in a fast motion and a quick burst
of light snow across the northern zones still looks like the best
this one will do. Afterwards, northwest flow aloft will back
toward zonal as a low-amplitude ridge moves across the region
early next week. As a result quiet and mild weather is expected
for Saturday through Tuesday. The next upper low to potentially
affect the region is progged for the middle of next week, however
there is a large variance in the models regarding the handling of
this system. That will be something to watch as we head through
the first week of 2021. Happy New Year, y'all.

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 6 AM CST Friday for TXZ024>026-
030>032-035>038-041>044.

&&

05/99/05

Hazardous Weather Outlook...UPDATED
National Weather Service Lubbock TX
657 PM CST Thu Dec 31 2020

TXZ021>044-020100-
Parmer-Castro-Swisher-Briscoe-Hall-Childress-Bailey-Lamb-Hale-Floyd-
Motley-Cottle-Cochran-Hockley-Lubbock-Crosby-Dickens-King-Yoakum-
Terry-Lynn-Garza-Kent-Stonewall-
657 PM CST Thu Dec 31 2020

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

.DAY ONE...Tonight.

A strong storm system will affect the region this evening and
overnight. Areas of snow and sleet will continue across the eastern
South Plains and redevelop in the Rolling Plains through the evening
and overnight hours. Snow accumulations up to three inches will be
possible across the Rolling Plains, with one-half to two inches
possible on the Caprock, mainly to the east of Interstate 27 and
Highway 87. A Winter Weather Advisory is in effect for this area
through 6 am Friday.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

Light wintry precipitation is expected across the extreme southeast
Texas Panhandle and northern Rolling Plains through mid-morning
Friday. Additional snowfall of one to two inches possible after
midnight. Then, another round of light snow showers is expected
across the far southern Texas Panhandle and northern portions of the
South Plains Friday night. Additional accumulations with this
activity should be under an inch.

Otherwise, no hazardous weather is expected after Friday.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LUBBOCK TX
726 PM CST THU DEC 31 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0720 PM     HEAVY SNOW       TAHOKA                  33.16N 101.79W
12/31/2020  M1.0 INCH        LYNN               TX   SOCIAL MEDIA

            APPROX. 1 HOUR'S WORTH OF ACCUMULATION.

&&

EVENT NUMBER LUB2100558

MCONDER

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LUBBOCK TX
827 PM CST THU DEC 31 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0826 PM     HEAVY SNOW       CROSBYTON               33.64N 101.24W
12/31/2020  E1.0 INCH        CROSBY             TX   LAW ENFORCEMENT

            ROADS ARE ICY.

&&

EVENT NUMBER LUB2100559

MCONDER