632
FXUS65 KRIW 172150
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
350 PM MDT Wed Jul 17 2024

.KEY MESSAGES...

- Stationary ridging keeps seasonally hot temperatures and light
  winds across the region for the next week or so.

- Showers and thunderstorms will be possible each afternoon
  through the end of the week. Most widespread
  showers/thunderstorms look to be Thursday afternoon.

- Low confidence in any notable pattern change for the next 7
  to 10 days.

&&

.DISCUSSION...
Issued at 252 PM MDT Wed Jul 17 2024

Have you been enjoying the weather for the past several days? Well,
whether you have or not, it will be much of the same for the
foreseeable future. A longwave ridge will remain nearly stationary
through the rest of the week and likely through much of next week as
well. A weak monsoonal push will strengthen over the next few days
resulting in diurnal showers and thunderstorms across the region.
Thursday looks to be the day with the most prolific widespread
moisture and associated shower activity as PWATs increase to 1" +/-
0.2" across much of the region, especially across central portions
of the region. A similar push of moisture looks likely for Friday as
well, though PWATs do not appear to be quite as high. Most
convection will be terrain enhanced, with showers developing along
the east slopes of most of our terrain features. Today, focus has
been primarily along the Bighorns and across the northwest portion
of our CWA so far, but as of 230 PM, convection is also firing up
along the Salts and Winds. Again, expect convection to be much more
widespread tomorrow given a weak wave that will push northeastward
out of Utah, and lead to further enhancement. One other note with
convection over the next few days is that these are fairly slow
moving storms, and with PWATs near to above normal, localized flash
flooding is an increasing concern. With the ridging, steering flow
is weak, and convection develops along the same terrain features,
leading to slow-moving and training cells. This will be a continued
threat through the end of the week.

The ridge does look to oscillate and shift slightly through the
weekend, but not appreciably. Hot, mostly dry weather continues to
be favored through much of next week, with continued afternoon
shower and thunderstorm chances. PWATs remain seasonal, so dry
thunderstorms are not a concern, and with generally light winds and
the shower activity, fire weather concerns remain limited. GFS and
ECMWF solutions do start to hint at a closed low pushing
southeastward into the PACNW late next week. This could help to
precipitate a pattern change, but confidence is low at this
time.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 349 PM MDT Wed Jul 17 2024

Any remaining showers and thunderstorms come to an end the first few
hours of the TAF period. All convection is done by 05Z, if not
sooner. Winds are light overnight, with a mostly clear sky. Shower
and thunderstorms are once again possible Thursday afternoon and
evening. Have PROB30 groups at most sites to cover this risk. As is
normal with diurnal convection, there is low confidence in exact
timing and location of showers/storms, so the PROB30 groups cover
the convective chances. Main threat with these showers will be gusty
outflow winds, generally up to around 30 knots being possible.

Smoke spreads from the northwest towards KCPR through Thursday
morning. The latest HRRR smoke shows the most dense smoke occurring
along and northeast a KCOD to KCPR line.

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

&&

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

&&

$$

DISCUSSION...Hensley
AVIATION...Wittmann