Area Forecast Discussion Issued by NWS Riverton, WY
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FXUS65 KRIW 020756
AFDRIW
Area Forecast Discussion
National Weather Service Riverton WY
1256 AM MST Tue Mar 2 2021
.SHORT TERM...Today through Thursday night
There are really almost no concerns for the first 42 to 48 hours of
the forecast period. High pressure will continue to bring mainly dry
weather with slowly moderating temperatures. There could be some
patchy fog in the Green River Basin this morning. In addition, gusty
winds will continue around Casper although with the pressure
gradient lessening a bit, winds should be somewhat less than the
past couple of days.
The only somewhat active weather will come courtesy of an area of
low pressure moving out of the desert southwest and tracking across
Colorado. The models have come into somewhat better agreement with
coverage of the precipitation. There will be a chance of some light
rain and snow across Sweetwater and possibly southern Lincoln
County. Impacts look minor at this point though; given that the best
moisture and energy will remain south of the area. Even if there is
some snow, with warmer ground temperatures and the March sun angle,
accumulation may be difficult on roads during the day. The
precipitation may end up being rain for the lower elevations. In
addition, the best QPF looks to remain south of Interstate 80 where
there are few people. All precipitation should end Thursday
afternoon with dry conditions returning Thursday night.
.LONG TERM...Friday through Tuesday.
Upper level riding will be in place across the Rockies on Friday
with tranquil weather and above average temperatures. A trough will
pull into the West Coast Friday night. Global models show the trough
weakening and splitting as it pulls across the Rockies in the
Saturday/Saturday night time frame. Strong southwest winds are
expected in the wind corridor including the Casper area Saturday,
but a widespread high wind event is not expected at this time. The
associated cold front is expected to pull across the forecast area
Saturday night and Sunday. Any light snow looks to occur mainly
along and west of the Divide and perhaps the south.
A stronger trough could impact the forecast area Monday night thru
Wednesday time frame depending upon the model. The upper jet
strength and position would be more supportive of heavier
precipitation across the forecast area than the one that occurs
during the weekend. The overall system is a bit fast, and the
progged 700mb low is too far north for a widespread significant
winter storm at the moment.
Seasonal to above average temperatures are expected through the long
term.
&&
.AVIATION...12Z Issuance
95 percent of the region will remain VFR through the next 24 hours
with clear skies. That final 5 percent is for a slightly greater
possibility at KBPI and KPNA for some morning fog through about
16Z. Winds will be light for most l=places Tuesday, except for
KCPR which will remain gusty tonight and through most of the next
24 hours.
&&
.FIRE WEATHER...
High pressure will continue to bring dry weather through most of
Wednesday night. A gusty will continue in similar spots to Monday,
but will be somewhat less strong than yesterday. Relative humidity
will remain above critical levels. Mixing and smoke dispersal will
be generally fair to poor. The next chance of rain or snow will be
Wednesday night but would likely be confined to far southern
Wyoming.
&&
.RIW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Hattings
LONG TERM...Murrell
AVIATION...Straub
FIRE WEATHER...Hattings