Latest ZFP from WFO RIW

		
National Weather Service Local Forecast for Star Valley Ranch
Updated: 10 May 11:05 am MDT

This Afternoon... Rain and snow likely before 2pm, then rain.
Some thunder is also possible.  High near 47. West wind 8 to 14 mph
becoming south southwest. Winds could gust as high as 21 mph.  Chance
of precipitation is 80%. Little or no snow accumulation expected. 

Tonight... Rain likely before 9pm, then a chance of rain and
snow. Some thunder is also possible.  Mostly cloudy, with a low around
30. East wind 6 to 14 mph, with gusts as high as 21 mph.  Chance of
precipitation is 70%. Little or no snow accumulation expected. 

Tuesday... A chance of rain and snow before 11am, then a chance
of rain between 11am and 5pm. Some thunder is also possible.  Mostly
sunny, with a high near 54. East northeast wind 6 to 14 mph becoming
west in the afternoon. Winds could gust as high as 21 mph.  Chance of
precipitation is 30%.

Tuesday Night... Partly cloudy, with a low around 31. West wind
6 to 13 mph becoming southeast in the evening. Winds could gust as
high as 20 mph. 

Wednesday... Mostly sunny, with a high near 59. South southeast
wind 6 to 14 mph becoming west in the afternoon. Winds could gust as
high as 21 mph. 

Wednesday Night... Partly cloudy, with a low around 36. West
wind 6 to 14 mph becoming south southeast after midnight. Winds could
gust as high as 21 mph. 

Thursday... Mostly sunny, with a high near 68. Breezy, with a
south southeast wind 6 to 15 mph becoming west in the afternoon. Winds
could gust as high as 23 mph. 

Thursday Night... Partly cloudy, with a low around 37.

Friday... A 20 percent chance of showers after noon.  Partly
sunny, with a high near 69.

Friday Night... A 20 percent chance of showers.  Mostly cloudy,
with a low around 42.

Saturday... A chance of showers.  Mostly cloudy, with a high
near 66.

Saturday Night... A chance of showers.  Mostly cloudy, with a
low around 40.

Sunday... A chance of showers.  Partly sunny, with a high near
64.

		

Latest AFD from WFO RIW

		
523 
FXUS65 KRIW 101758
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
1158 AM MDT Mon May 10 2021

.SHORT TERM...(Today through Tuesday)
Issued at 233 AM MDT Mon May 10 2021

With the H5 trough slowly dropping southeast across ID/UT, 
westerly flow ahead of it across CO will be inducing lee 
cyclogenesis there. This will bring the surface wind field more 
from the east across the state today. Currently looks like the 
winds will have a northeasterly component, so best upslope effects
still expected across the eastern Winds today, and the Eastern 
Salts/Wyomings and the Absarokas this evening and tonight. Snow 
levels hover between 6000 and 7000 today and around 6000 feet 
tonight, with accumulations remaining above 6500. As the trough 
moves east tonight into Tuesday, the region transitions to a NW 
flow, reducing the snows on the Winds, while bringing some snow to
the Big Horn range. Overall accumulations for all higher 
elevations range 4 to 8 inches, with a few spots in the Winds 
maybe reaching 10 inches. 

Temperatures will be noticeably colder today, with highs mainly 
in the 30s and 40s. as the cold pool moves east with the trough, 
some recovery will be noted Tuesday, with highs back in the 50s 
and low 60s, albeit with mostly cloudy skies continuing.

.LONG TERM...(Tuesday night through Sunday)
Issued at 233 AM MDT Mon May 10 2021

Lingering showers in the north will start the long term. There 
will be a ridge to the west of Wyoming, with northwest flow across
the state. The pattern will be a bit on the dirty side. Models 
are indicating minor shots of energy transiting the ridge, 
bringing isolated showers, mainly to the north and northwest 
through Friday. The majority of the forecast area will have dry 
weather and warmer temperatures. This pattern of afternoon showers
and convective activity will continue through Friday. Thursday to
Saturday will be warmer, with high temperatures in the 60s and 
70s, with 40s and 50s in the mountains. Lows will be in the 40s, 
with 30s in the west.

Saturday will see the ridge axis finally transiting across Wyoming, 
with continued showers, mainly across the northwest. A trough moving 
in behind the ridge will continue the shower activity through 
Sunday. Models are still trying to decide on the  exact timing and 
location of this next feature, all though PoPs are definitely 
showing up. High temperatures will drop off a little on Sunday, but 
still into the 60s to lower 70s with 40s and 50s in the mountains.

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)

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

Will continue with the VCSH trending as per the previous forecast
as scattered precip is continuing across the area. MVFR to IFR 
conditions will be the most predominant through this afternoon. 
Most activity will remain as rain across the TAF sites with the
exception of KLND. Will keep in the mention of a rain/snow mix
there. Mountains remain obscured through the day. Will keep in the
mention of the VCSH through the forecast due to the expected
scattered precipitation.

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

Isolated to Scattered showers will continue for KJAC/KBPI/KPNA
through this afternoon, with the precipitation becoming more 
numerous tonight. Any showers that do pass will bring brief MVFR 
cigs and visibilities. Have kept in VCSH mention through the
forecast period due to the expected scattered showers. Mountains 
will be partially obscured.

&&

.FIRE WEATHER...
Issued AT 233 AM MDT Mon May 10 2021

Shower activity returns today, with accumulating snowfall for
elevations above 6500 feet. Cloud skies and cooler weather keeps
humidity levels elevated through the middle of the week. Gusty
winds will be limited to zones 280 and 289 the next couple days,
but will remain below 25 mph.

&&

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

$$

SHORT TERM...Straub
LONG TERM...Swanson
AVIATION...Troutman
FIRE WEATHER...Straub