Winter Storm in Colorado, March 21, 2022

Area Forecast Discussion
National Weather Service Goodland KS
520 AM MDT Mon Mar 21 2022

.SHORT TERM...(Today through Wednesday)
Issued at 346 AM MDT Mon Mar 21 2022

The short term period starts out with a difficult forecast with the
approaching storm system. Short term, high resolution guidance has
begun trending more to wet side with the approaching system,
differing from the drier trend from the past few forecast
packages. The reasoning for this appears to be a more western
progression of the system than what was seen in the previous
forecast package which showed more of a progressive system.
Temperatures will steadily drop through the day as an approaching
cold front moves in from the NW. Precipitation is anticipated to
overspread the southern portion of the area, starting out as
mainly rain before becoming a rain/snow mix and then finally to
all snow around mid day as temperatures cool to near freezing. The
precipitation type is very challenging as a rate driven snow is
expected, similar to event earlier in the week. A Winter Weather
Advisory has been issued for Yuma, Kit Carson, Cheyenne (CO),
Wallace, Sherman, and Cheyenne (KS) from 6a to 6p MT. The advisory
was issued for the potential for moderate snowfall and strong
winds up to 50 mph developing through west to east throughout the
morning creating near blizzard conditions in spots. If this were
to develop Interstate 70 and other area highways may be impacted
with visibilities falling to a half mile or potentially less at
times. Uncertainty does exist on the duration of the stronger
winds and the overall extend of areas of reduced visibilities. As
mentioned above precipitation type is very challenging with this
system as a longer transition over to all snow would significantly
lower snowfall accumulations. The warm soil and road conditions
may overall temper the amount of actual snowfall as well,
irregardless reduced visibilities can be expected within any
areas of snowfall.

Into tonight, the area of rain and snow is expected to move to the
east. Additional winter weather advisories may be needed throughout
the day and into the night. The NAM indicates a potentially
convective band of heavier snowfall developing across the eastern
portion of the area due to 850-700mb frontogenesis. Theta E Lapse
rates are slightly below zero which indicates this potential for
convectively driven snowfall to occur. Winds are expected to
intensify overnight as the low pressure system fully matures. GFS
forecast soundings indicate very strong flow (~50+knots) within
the mixing layer across the area. Opted to hold off on any wind
products as concern that the full mixing may not be able to be
fully realized as the CAA isn't very strong and there is a lack of
pressure rises with the system which would support the mixing
down of the stronger winds. Nevertheless, the potential does exist
for reduced visibilities overnight tonight within any areas of
snowfall as wind gusts up to 50 mph are still expected.
Surrounding offices have a Winter Weather Advisory out for
counties surrounding the CWA; opted to hold off on that area due
to 1) to avoid any potential confusion, as the western CWA
advisory has been issued and 2) cautiously skeptical due to
recent uptick in overall qpf and snowfall amounts, will be passing
that off to the day shift for one more run of guidance to ensure
a drier trend doesnt return.

Tuesday, strong winds will continue through the day as rain/snow
chances end west to east throughout the morning. The potential for
strong winds of 50+ mph continues to exist according to forecast
soundings; again held off on any highlights due to the concerns
noted above. Decreased high temperatures across the area as cooler
air is expected to move into the area behind the low, current
forecasted highs are currently in the lower 40s to low 50s across
the area. Clouds will become less numerous during the afternoon,
setting up for a cooler night across the area as overnight Tuesday
temperatures fall into the 20s. A slight chance exists on Wednesday
for some wraparound light rain and snow with minimal moisture is
possible across the eastern portions of the area. Winds will remain
breezy, but not as strong before waning west to east during the
afternoon hours.

.LONG TERM...(Wednesday night through Monday)
Issued at 112 AM MDT Mon Mar 21 2022

The latest runs of the GFS/ECMWF show the region under northwest
flow aloft starting midweek, but towards the end of the week 500mb
low will shift east from the Rockies and eventually crest over the
Plains region for Sunday and next Monday. During the expected
northwest flow, there are hints of a few weak shortwaves that may
impact portions of the area in the Fri-Sat timeframe. Uncertainty in
guidance at this time, so will leave out mention of. By next Monday
though, both models do show another system approaching the area
which currently may dive south of the area leaving a potential low
chance for some light rain. Plenty of time to watch the track of
this system, but will leave in mention of light rain for northeast
Colorado and portions of southwest Nebraska.

With the region expecting a shift with the upper ridge to our west,
an increased temperature trend is expected, peaking into the latter
portion of next weekend into next Monday. The above normal warmth
for this 2-day period, combined with dry weather for much of the
extended, will bring about some elevated fire wx concerns Sun-Mon.
The area of concern at this time will be areas along/west of Highway
27. RH values will be in the upper teens/lower 20s and winds mainly
in the 15-20 mph range at this time. This will need to be monitored
as the movement of the lee-side trough in this timeframe will
dictate areal coverage of elevated fire wx concerns.

For temps, looking for daytime highs on Thursday and Friday to range
in the mid 50s thru about the lower 60s. Going into next weekend,
Saturday will be warmer in the mid to upper 60s, mid to upper 70s
for Sunday, and by next Monday lower to mid 70s.

Overnight lows in the extended will start with 20s Wednesday night,
30s Thursday night then dropping back slightly for Friday night with
upper 20s to lower 30s. Going into next weekend, the area will see
30s for Saturday night, 40s for Sunday night then back lower to the
mid 30s to lower 40s for next Monday night. Warmest areas east.

&&

.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
Issued at 509 AM MDT Mon Mar 21 2022

Poor aviation conditions are anticipated to develop today as a
storm system moves into the area. LLWS looks to continue for a few
hours at KGLD after TAF issuance but is anticipated to dissipate
by mid morning. Rain and snow showers will overspread the area
during the day, mainly affecting KGLD during the first 12 hours.
Winds will increase mid to late morning with gusts of 40-50 mph
possible and will have the potential to create blowing snow which
will inhibit visibility. The rain and snow will move east
throughout the afternoon and evening and look to move into the
KMCK vicinity during the late afternoon. Winds will remain strong
from the NNW for the entire duration of the period and into the
following period as gusts of 50 mph remain possible.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...Winter Weather Advisory until 6 PM MDT /7 PM CDT/ this evening
     for KSZ001-013-027.

CO...Winter Weather Advisory until 6 PM MDT this evening for
     COZ090>092.

NE...NONE.
&&

SHORT TERM...TT
LONG TERM...JN
AVIATION...TT

Hazardous Weather Outlook
National Weather Service Goodland KS
305 AM MDT Mon Mar 21 2022

COZ090>092-KSZ001>004-013>016-027>029-041-042-NEZ079>081-220915-
Yuma-Kit Carson-Cheyenne-Rawlins-Decatur-Norton-Sherman-Thomas-
Sheridan-Graham-Wallace-Logan-Gove-Greeley-Wichita-Dundy-Hitchcock-
Red Willow-
305 AM MDT Mon Mar 21 2022 /405 AM CDT Mon Mar 21 2022/

This hazardous weather outlook is for extreme southwest Nebraska...
northwest Kansas and east central Colorado.

.DAY ONE...TODAY AND TONIGHT...

Rain and snow will transition to all snow during the morning hours
with areas of blowing snow as winds gusts up to 50 mph along and
west of Kansas Highway 27. Near blizzard conditions are possible at
times. A Winter Weather Advisory has been issued for Yuma, Kit Carson
and Cheyenne counties in Colorado along with Sherman, Cheyenne and
Wallace counties in Kansas from 6am MT to 6pm MT.

Snow and winds will continue through the overnight hours while moving
to the east creating hazardous driving conditions. Wind gusts up to
50 mph are possible.

Residents and travelers are encouraged to monitor forecast updates
as this early week system moves across the Plains. Sudden changes in
the weather conditions are possible.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY...

Light snow will continue through Tuesday with strong northerly winds
up to 50 mph. These winds will create areas of reduced visibilities
due to falling snow and making driving difficult.

Elevated fire weather returns Sunday and Monday along and west of
Kansas Highway 27.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected today. Reports of snowfall and
reduced visibilities are appreciated today and tonight however.