Area Forecast Discussion
Issued by NWS Riverton, WY

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

917
FXUS65 KRIW 162012
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
212 PM MDT Wed Jun 16 2021

.SHORT TERM...(This evening through Thursday night)
Issued at 211 PM MDT Wed Jun 16 2021

The upper-level ridge that has been responsible for the record
setting heat will begin to flatten to more zonal flow behind a weak,
dry cold front that is slowly making its way through the area. As
the upper-level flow begins to flatten out, temperatures will
continue to decrease from yesterday`s records. By tomorrow
afternoon, we`ll see upper 80s to lower 90s while still remaining
dry. This does however, keep elevated to critical fire weather
conditions on the doorstep through the period. The above average
temperatures and below average precipitation trend looks to continue
into the long-term period. Also, have relayed from DEQ an air
quality alert for wildfire smoke moving down into the Bighorn
Basin and surrounding mountains.

.LONG TERM...(Friday through Wednesday)
Issued at 211 PM MDT Wed Jun 16 2021

A dry westerly flow is expected Friday. A trough is expected to pull
southeast out of southwest Canada across the northern Rockies
Saturday night and Sunday. The associated cold front is also
expected pull across the forecast area Saturday night into Sunday.
In wake of this cold front, there appears to be a decent chance of
precipitation east of the Divide especially on Sunday. This
precipitation is then expected to exit the area Sunday night. There
might be enough cold air with this system where the precipitation
above 8500 feet could be snow. Upper level ridging builds into the
region Tuesday and Wednesday with a return of very warm temperatures
and mainly dry conditions.

&&

.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1053 AM MDT Wed Jun 16 2021

East of the Divide...KCOD/KCPR/KLND/KRIW/KWRL Terminals

The main issue will be wildfire smoke impacting KCOD at times due to
northerly winds pushing smoke southward into the area. Although
surface visibility is expected to be P6SM this afternoon and
Thursday afternoon, the glide slope could see reductions in
visibility. MVFR visibilities at the surface could occur at times
mainly tonight and Thursday morning. The rest of the terminals
will be VFR through the TAF period. In wake of a cold front this
morning, winds will generally be north to east this afternoon, but
some mixing should allow for a southwest to west wind to develop
in the Wind River Basin impacting KRIW and KLND. Winds will
generally become light during the evening hours. Breezy westerly
winds are expected to develop around midday Thursday at KCPR, KLND
and KRIW.

West of the Divide...KBPI/KJAC/KPNA/KRKS Terminals

VFR conditions with only some high clouds are expected through the
TAF period. Breezy west southwest winds, more southerly at KJAC,
this afternoon will weaken this evening, but will redevelop around
midday Thursday.

&&

.FIRE WEATHER...
Issued AT 211 PM MDT Wed Jun 16 2021

A dry cold front has moved through the northern fire zones with
brief relief in temperatures and little improvement in minimum
relative humidity. A strong, westerly wind this afternoon, mainly in
the southern zones could exceed elevated to critical fire weather
conditions. High pressure is expected to remain over the area the
next several days with the potential for another cold front Saturday
night into Sunday.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...Vorst
LONG TERM...Murrell
AVIATION...Murrell
FIRE WEATHER...Vorst



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.