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fxus65 kriw 222210 

Area forecast discussion
National Weather Service Riverton Wyoming
310 PM MST Fri Nov 22 2019

Short term...tonight through Monday

Well, the fog monster made an appearance in several places last
night and overstayed his checkout in some of the basins, recking
havoc to portions of the area. It has finally lifted at this point.
The question is will he make an encore appearance tonight. Things do
not look quite as favorable for it tonight. However, there could be
some, although it would be more of the lower elevation ground fog
than today. For now, we have gone with patchy fog in the favored
basins but at this point it does not look as widespread as last
night. Meanwhile, breezy conditions will occur in the favored areas,
like the Lee of the absarokas and from the Red Desert through Casper
that will keep temperatures a bit warmer.

Mainly dry conditions will continue through most of Sunday with a
gradual warming trend. Breezy to windy conditions will continue as
well. There could even be some high winds in spots. The main threat
area will be in the Lee of the absarokas from late Saturday night
into Sunday ahead of an advancing cold front. The models are showing
some 50 to 60 knot winds in the absarokas and could bring some
strong winds to the surface. This would be mainly near Clark where
high wind criteria is higher and still some uncertainty so no
highlights at this time.

The aforementioned cold front then drops across the state Sunday
night into Monday. All the models have some quantitative precipitation forecast with a special
emphasis on the western mountains. There is not much agreement on
the exact details just yet in regards to timing though. In addition,
the models have a lot of differences in placement of the heaviest
precipitation. And with the banded nature of the qpf, it is almost
impossible to nail down an area this far out. For now, we went with
higher amounts in the areas of agreement, mainly the west and
southern Sweetwater County. Elsewhere, we kept amounts generic until
the details can be hashed out a little better.

Long term...Monday night through Friday

Monday night precipitation will be decreasing as the trough pushes
southeastward. However, the reprieve will be short lived and could
be more of a lull as the next wave of activity moves into western
Wyoming possibly as early as Tuesday morning. This batch of showers
will be due to a trough moving onto the West Coast and funneling
moisture into the area. Southwest flow will set up over the region
as the trough digs southward. Scattered snow showers are expected
across the west on Tuesday. Then, exact timing is still
uncertain, but Wednesday into Thursday, snow spreads across the
rest of the state with the majority of snow still falling across
the west. Models have slowly pushed timing with this system back
and more consistency is needed for a confident forecast.
Regardless, a snowy Thanksgiving Holiday seems likely for the
cowboy state. Not to dampen spirits further, but this system will
also bring gusty winds to prone locations across the area and cold
temperatures. High temperatures look to be in the 20s to low 30s
for most areas through the end of the week.


Aviation...00z issuance

All taf sites have made it to VFR this afternoon. VFR conditions
will continue through the taf period with the exception of more
fog Saturday morning for kriw and klnd. SW wind gusts continue at
kcpr and krks. Gusts will slack off at krks after sunset, but only
decrease, not stop, at kcpr. Gusts at kcpr will gradually increase
after 16z Saturday. Both krks and kcod will gust from late morning
through Saturday afternoon. Otherwise, some high level clouds will
begin to drop down from the north towards the end of the period.


Fire weather...

Mainly dry weather will continue through much of the weekend. Other
than some patchy fog each morning, expect a mix of clouds and
sunshine with a gradual warming trend. Inversions will likely
persist in some of the basins through Friday. Breezy to possibly
windy conditions are possible in the Lee of the absarokas and from
the Red Desert through Casper. Mixing and smoke dispersal will be
generally poor in most locations but fair to good across southern

Riw watches/warnings/advisories...


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