878
FXUS65 KCYS 181151
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
551 AM MDT Mon Aug 18 2025

.KEY MESSAGES...

- A slight risk (2 of 5) of severe weather is expected today,
  with the most likely area for stronger storms the easternmost
  counties of the Nebraska Panhandle.

- Hot temperatures with more limited thunderstorm chances are
  expected Tuesday through Thursday.

- A cold front late in the week should bring back rainfall
  chances and cooler temperatures leading into the weekend.

&&

.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 310 AM MDT Mon Aug 18 2025

Analysis of high resolution guidance shows the HRRR is doing a
pretty solid job picking up on the ongoing thunderstorms across
the southern counties of the border between WY/NE, which fired
off of the intersection of boundaries that passed across the
region overnight. Because of this, the short term forecast will
utilize this model as it has been handling convection across
our area fairly well over the past few days. Guidance across all
models indicates another round of afternoon convection today
fueled by modest instability but limited due to poor low level
moisture. These storms should fire off during the mid to late
afternoon hours and continue into the early evening, with the
best instability fueling the strongest activity across the far
eastern counties of the Nebraska Panhandle. Any storms will be
capable of strong winds or large hail, but models do indicate
some clustering of the activity along the southern counties of
the Nebraska Panhandle which gives the best risk for severe wind
gusts.

Today should then be the last day we see noteworthy precipitation
chances for a couple of days as the Four Corners ridge
strengthens and takes hold of our area through the middle of the
week. This will encourage a warming trend that will see our
temperatures rising a few degrees each day through Wednesday.
Highs today will range between the mid 80`s to mid 90`s, while
highs tomorrow will peak in the upper 90`s for portions of the
Nebraska Panhandle and perhaps the border into far eastern
Wyoming as well. With the increasing heat comes decreasing
moisture, bringing an enhanced risk of fire weather concerns for
our area as well. Thankfully with a weak pressure gradient
we`ll struggle to produce stronger winds that would bring
critical fire weather concerns, but we will monitor into the
middle of the week if any areas will need watches or warnings.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Issued at 310 AM MDT Mon Aug 18 2025

Wednesday begins the long term as one of the hottest days of the
week under the Four Corners ridge, with 90`s to triple digits
possible for the day and dry conditions. Thursday a cold front
will begin moving into the region and should help to alleviate
some of the heat for far northwestern counties of our CWA in
Wyoming, but for the rest of the region even hotter temperatures
can be expected with more widespread triple digits in the
Nebraska Panhandle. Thankfully the aforementioned frontal
boundary will continue to progress across the region driven by a
deep upper low over Canada. This low will slowly move eastwards
through the weekend, and bring cooler northwesterly flow, more
moisture, and multiple smaller embedded systems that will
produce near daily showers and thunderstorms beginning Thursday
and continuing through the rest of the long term period. Highs
should descend back into the 70`s to mid 80`s, a notable
cooldown. Meanwhile, though the moisture won`t be abundant, daily
showers and storms should be possible for a majority of the CWA
and current QPF totals show around a tenth to a half inch from
Thursday through Sunday. Those not looking forward to the summer
heatwave we`ll experience through the middle of the week should
be encouraged that our end of week and weekend looks notably
cooler with more chances for rain, a sign of fall to come.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 534 AM MDT Mon Aug 18 2025

VFR conditions expected over the next 24 hours outside of any
strong to severe thunderstorms that pass over sites, which could
bring locally MVFR or lower conditions from heavy rainfall.
Thunderstorms most likely during the afternoon and early evening
hours, with the strongest storms expected in the Nebraska
Panhandle, most likely to affect those terminals. Overall
prevailing winds should be on the light side, generally 5 to 15
knots, though some rare stronger gusts could be possible, with
gustier and erratic/variable winds possible near or under any
passing thunderstorms. CIGs remaining mid to high level, 10-20k
feet, with skies clearing tonight after storms move out of the
region.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.

&&

$$

SHORT TERM...CG
LONG TERM...CG
AVIATION...CG