Casper, Wyoming 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

246
FXUS65 KRIW 141120
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
520 AM MDT Mon Apr 14 2025

.KEY MESSAGES...

- Dry and seasonable today with a gusty wind for Johnson and
  Natrona Counties.

- Warmer and remaining dry Tuesday and most of Wednesday.

- Turning colder Thursday with a chance of snow and rain
  changing to snow Thursday through Friday.

&&

.DISCUSSION...
Issued at 158 AM MDT Mon Apr 14 2025

Spring, especially April, seems to be a month when we can get the
biggest variety of weather across the Cowboy State, as warmer
temperatures from southerly flow and a strengthening sun angle (we
are now back to a late August sun angle) compete with some still
cold air masses coming in from Canada and winter holding on for dear
life. And at this point, it looks like we will see a variety of this
weather.

The first 60 hours or so will be the tranquil and more spring like
weather. Today will be a dry day across the area. Flow will be
generally from the north or northwest, so temperatures will be near
to somewhat below normal. And there will still be a gusty wind in
eastern portions of the area, mainly Johnson and Natrona Counties.
This is courtesy of a decent pressure gradient and the right front
quadrant of a jet streak passing across northern portions of the
area. The strongest wind will be in Johnson County, but no where
near as strong as yesterday, when many locations had gusts over 60
mph. Otherwise, it looks a seasonal, mid April day across the area.
Tuesday is shaping up to be a very nice Spring day though. One of
those days with comfortably warm temperatures (about 10 to 15
degrees above normal) and plenty of sunshine as flow turns
southwesterly. There will be a bit of a breeze in the favored
southwesterly flow locations though, mainly from Muddy Gap
through Casper, but the kind of breezy we call Tuesday in these
parts. It could bring elevation fire weather though.But, enjoy
this day as it looks like we will have a major pattern change
coming later in the week.

Wednesday should remain dry and warm for most locations. However,
southwest wind will be increasing as a system moves out of Canada
and into Montana. A few showers will be possible in western Wyoming
in the afternoon, but even here most of the day should be dry. There
could even be a few thunderstorms as the cold front approaches. And
as we head into Thursday and Friday, things could get potentially
more interesting. This system will have much colder air with it,
with 700 millibar temperatures falling to under minus 8 in many
locations East of the Divide by Thursday evening. And that means we
could be seeing some snow for many locations Thursday into Friday.
The quandary we have here is that model guidance is still all over
the place. There are a lot of moving parts with this system and this
makes pinpointing the heaviest precipitation very difficult and even
the timing of the heaviest precipitation hard to pin down.
Complicating this further is that with the warm ground and high sun
angle, a lot of the snow may not stick during the day. As for the
probabilistic guidance, the NBA ensemble is giving a greater than 1
in 2 chance of over 3 inches of snow for many locations East of the
Divide with a 1 in 2 chance of over 6 inches of snow across the
favored northerly upslope locations like Lander, Thermopolis and the
south side of Casper by Friday evening. Confidence is still low
though. At this point, all precipitation should end by Friday
evening with dry weather returning for Saturday as ridging builds
over the area. Temperatures will remain would likely remain below
normal from Thursday through the weekend.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 518 AM MDT Mon Apr 14 2025

VFR conditions continue through the next 24 hours, with minimal
to no cloud cover expected. Winds will generally be from the
west and northwest today, with gusts above 15kts limited to KCPR
this afternoon. Winds lower to around 5kts for all sites
overnight tonight.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Hattings
AVIATION...Straub