095
FXUS65 KRIW 101747
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
1147 AM MDT Thu Jul 10 2025

.KEY MESSAGES...

- Widely scattered rain showers will continue over the southern
  half of the forecast area this morning. Isolated showers will
  be possible across areas east of the Divide this afternoon.

- A cold front will move over areas east of the Divide early
  Friday morning, becoming stationary along the Divide. Highs in
  the 70s will be widespread in these areas as a result.

- Dry conditions and a warming trend over the weekend with
  elevated fire weather conditions returning by Sunday.

&&

.DISCUSSION...
Issued at 120 AM MDT Thu Jul 10 2025

Weak showers will continue over the southern half of the CWA this
morning, as a remnant low approaches the area from southern ID. Any
rainfall amounts will be very low, a trace to 0.02", along with very
isolated lightning strikes. Showers will remain isolated over this
area through the rest of the morning after sunrise, as the low
reaches far southern WY. The focus for precipitation will shift east
of the Divide this afternoon, as the low exits over eastern portions
of the state. Wind gusts of 50 to 55 mph will be the main threat,
along with some lightning. Instability will be limited, as CAPE
values will range between 200-500 J/kg. Temperatures will be about
10 degrees cooler across the CWA as a result of the passage of this
remnant low. Fire weather conditions will remain elevated as well,
with critical RH values returning to portions of the Wind River and
Bighorn Basins and Sweetwater County.

A cold front will reach northern WY sometime between 06Z and 12Z
Friday, quickly progressing southward and reaching the Divide by
15Z. Any precipitation looks to be confined to northern portions
through much of the day Friday, but could progress into the Wind
River Basin in the afternoon. Any thunderstorms look to occur along
the Divide, due to the front. Highs in the 70s east of the Divide
remains in the forecast, while areas west of the Divide stay in the
low to middle 80s. Locations in northern Johnson County may not
reach 70 degrees, which would be a 30 degree dip from yesterday.

Dry conditions then return for the weekend, with a somewhat
northwest flow pattern aloft. This will lead to seasonal
temperatures on Saturday and highs in the 90s return for areas east
of the Divide on Sunday. Showers and thunderstorms could be possible
Monday and Tuesday, as another trough drops south from British
Columbia and bringing the trough/cold front through Tuesday
night.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1145 AM MDT Thu Jul 10 2025

Latest model runs have removed most mentions of showers and
thunderstorms for this afternoon or have decreased chances to less
than 20 percent. The exception is KCPR. Though showers and
thunderstorms look to stay to the east of the KCPR Terminal,
have included a PROB30 group to cover the 20-30% chance that
showers and/or thunderstorms could develop farther west, and
thus impact the terminal.

Models remain on track with the cold frontal passage overnight and
Friday morning. There are slight indications of showers developing
along and in the wake of the front, however, confidence is low. Most
likely chances are at KCOD (30% chance), KWRL (20% chance) and KCPR
(20% chance). Generally, the more likely impact looks to be lowering
cigs at the aforementioned terminals. VFR conditions look to
prevail, but for KCOD and KCPR, there is a 20-30% chance of MVFR
cigs developing behind the front Friday morning.

Also with the frontal passage, northerly to northeasterly winds are
expected at most east of the Divide terminals and at KRKS Thursday
night through Friday morning. Gusts to 20 to 25kts are expected and
could linger through much of the morning, though do look to
gradually taper off at most terminals by the later half of the
morning.

Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for
the latest information on smoke, icing, and turbulence forecasts.

&&

.FIRE WEATHER...
Issued at 120 AM MDT Thu Jul 10 2025

Elevated fire weather conditions will return for one more day
today, with critical RH values occurring along eastern portions
of the Bighorn Basin, the Wind River Basin and Sweetwater
County. Winds will not be a contributing factor, however gusty
outflows could occur (20% chance) from showers over the
Absaroka, Bighorn and Wind River Mountains this afternoon.

&&

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

&&

$$

DISCUSSION...LaVoie
AVIATION...Hensley
FIRE WEATHER...LaVoie