Sidney, Nebraska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

952
FXUS65 KCYS 040549
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
1149 PM MDT Sun May 3 2026

.KEY MESSAGES...

- Widely scattered showers and isolated thunderstorms are
  expected this afternoon and evening, and may produce gusty and
  erratic winds.

- An powerful cold front arriving Monday will bring a chance
  for showers and thunderstorms, changing over to snow Monday
  night and continuing into Wednesday morning.

- Accumulating snowfall is likely (70% chance) over 6000 feet in
  elevation, with significant snowfall possible in the Snowy
  Range, southern Laramie Range, and their adjacent foothills.

- Drier, warmer, and windier weather returns to the area for the
  second half of the work week.

&&

.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 216 PM MDT Sun May 3 2026

Now:  Some storms are popping up across Campbell county and are
slowly dipping south into Converse and Niobrara county. These storms
are currently producing lightning with some rain possibly hitting
the ground but would still need to watch out for any fires started
by dry lightning. There are also a couple showers that is producing
mostly virga with a couple spits of rain in Central Laramie County
and crossing the Colorado border. The HREF shows some modest CAPE
that these storms could utilize along the Northern border of our
forecast area.

Monday and Tuesday: A cold front will push through Monday morning to
kick off some rain showers in the early afternoon. The surface cold
front is expected to pass through during the day. This may reach
Douglas to Chadron by 7AM or so, stunting high temperatures there
for the day. The front should reach the I-80 corridor by midday. As
a result, expect most areas to see a morning or early afternoon high
temperature, with gradual cooling through the afternoon hours. After
sunset, temperatures will begin to rapidly cool. The surface front
will slow down as it pushes up against the higher terrain of
southern Wyoming and northern Colorado, leading to frontogenesis.
Forecast soundings along the I- 80 corridor Monday afternoon look
nearly saturated with fairly steep lapse rates in place. SBCAPE
could locally exceed 1000 J/kg. Strong forcing provided by the
frontogenesis and moderate overrunning flow should kick off numerous
showers and scattered thunderstorms around midday Monday, mostly
along the I-80 corridor. A few stronger storms capable of producing
hail and gusty winds cannot be ruled out. By the evening into the
overnight hours the rain will transition to snow across the southern
half of the forecast area. The mountains will likely transition into
snow the quickest due to the higher elevation. The lower elevations
are expected to switch a lot slower leading to more of a rain/snow
mix through the overnight period. Majority of model guidance depicts
strong a strong band of FGEN with some isentropic lift to increase
the precipitation rates and lead to greater accumulations. The LREF
shows a 25/75th percentile of 3 to 8 inches of snow for Central
Laramie county and between 5 to 11 inches for the foothills/summit
area. Due to the favorable upslope flow the Snowy range could see
between 13 to 18 inches depending on elevation. The models also show
the band of FGEN to be pretty progressive through our area, however
the mountains may hinder it some leading to possibly higher amounts
on the mountain. The Sierra Madres are expected to be mostly
shadowed by the Snowies this event so up to 6 inches is expected for
that range. Since Laramie also sits in bowl, there`s also some
potentially shadowing for the town as well leading to lower
accumulations than the rest of the area.  Accumulations will also
depend on the timing, as snow falling during the day will be much
less likely to stick and accumulating thanks to the very strong
early May sun. We will therefore wait a little longer for confidence
to improve before including lower elevation zones in any winter
weather headlines. However, if this plays out like the models are
anticipating then an Advisory or a winter storm warning may be
needed for the lower elevations in the mountains and also possibly
for Laramie county as well.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Issued at 410 AM MDT Sun May 3 2026

Strong ridging will try to build back into the western US
immediately after this storm system. While Wednesday will still
feature temperatures well below average for this time of year,
expect warmth to recover quickly. Highs around 5F above average can
be expected on Thursday, climbing closer to 10F above average by
Saturday. Northwest flow will kick up quickly behind the departing
trough axis on Wednesday, and lead to breezy to windy conditions.
The strongest winds are anticipated on Thursday, when the southeast
Wyoming wind prone areas continue to have a 20 to 40% chance for
high winds. Both Thursday and Friday will feature isolated to widely
scattered PM showers and perhaps a few thunderstorms, but rainfall
expectations are limited at best. Precipitation potential will tick
up over the weekend a progressive upper level low approaches the
area from the northwest. The details concerning this system remain
highly uncertain at this lead time.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1135 PM MDT Sun May 3 2026

VFR conditions will prevail through Monday morning, but expect
big chances Monday afternoon onward. A cold front will sweep
through the High Plains Monday morning, reaching CDR around
13-14z, and CYS and SNY around 18z to 20z. This will bring a
shift of the winds to the north or northeast, with gusts of 25
to 30 knots expected.

Scattered showers and isolated thunderstorms will develop along
the I-80 corridor early Monday afternoon which will have the
potential to bring gusty and erratic winds as well as brief VIS
drops in moderate rainfall. Shower activity will increase in
coverage along at least the I-80 corridor terminals, and perhaps
into BFF, AIA, and CDR as well. Flight category will be trending
downwards with CIGs reaching MVFR Monday evening, and possibly
IFR before midnight. Snow may start to mix in with the rain at
Wyoming terminals towards the very end of the TAF period.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Winter Storm Watch from Monday evening through Wednesday
     morning for WYZ110-114-116-117.
NE...None.

&&

$$

SHORT TERM...MM
LONG TERM...MN
AVIATION...MN