Latest ZFP from WFO RIW

		
National Weather Service Local Forecast for Star Valley Ranch
Updated: Mon Mar 31  3:43 am MT

Overnight... Scattered snow showers.  Mostly cloudy, with a low
around 28. South southeast wind around 7 mph.  Chance of precipitation
is 50%. Total nighttime snow accumulation of less than a half inch
possible. 

Monday... Snow showers before 3pm, then rain and snow showers.
Some thunder is also possible.  High near 40. Southeast wind 6 to 9
mph becoming west southwest in the afternoon.  Chance of precipitation
is 90%. New snow accumulation of around an inch possible. 

Monday Night... Snow showers. Some thunder is also possible. 
Low around 21. South southwest wind 6 to 8 mph becoming east northeast
in the evening.  Chance of precipitation is 90%. New snow accumulation
of around an inch possible. 

Tuesday... Snow showers likely.  Mostly cloudy, with a high
near 35. West wind 7 to 10 mph.  Chance of precipitation is 70%. New
snow accumulation of less than a half inch possible. 

Tuesday Night... A 50 percent chance of snow showers.  Mostly
cloudy, with a low around 24. West wind 5 to 9 mph becoming light 
after midnight.  Little or no snow accumulation expected. 

Wednesday... Snow showers likely, mainly after noon.  Mostly
cloudy, with a high near 38. West northwest wind 3 to 6 mph.  Chance
of precipitation is 70%.

Wednesday Night... A 30 percent chance of snow showers before
midnight.  Mostly cloudy, with a low around 22. West northwest wind
around 6 mph becoming calm  in the evening. 

Thursday... Snow showers likely, mainly after noon.  Partly
sunny, with a high near 42. Chance of precipitation is 60%.

Thursday Night... A 20 percent chance of snow showers before
midnight.  Partly cloudy, with a low around 21.

Friday... A 50 percent chance of snow showers, mainly after
noon.  Mostly sunny, with a high near 44.

Friday Night... A chance of snow showers.  Partly cloudy, with
a low around 22.

Saturday... A slight chance of snow showers.  Mostly sunny,
with a high near 47.

Saturday Night... Mostly clear, with a low around 21.

Sunday... Sunny, with a high near 51.

		

Latest AFD from WFO RIW

		
566 
FXUS65 KRIW 311046
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
446 AM MDT Mon Mar 31 2025

.KEY MESSAGES...

- Showers push back in from the west Monday morning, with 
  mountains snow west of the Divide and mainly rain for lower 
  elevations.

- Precipitation spreads east of the Divide late Monday 
  afternoon and overnight, with high elevation snow and lower 
  valley rain although accumulations look to be light. 

- Showers linger into Tuesday with another round across 
  northern parts of the area overnight into Wednesday.

- Dryer to end the week and into the weekend with warmer
  temperatures expected through early next week.

&&

.DISCUSSION...
Issued at 105 AM MDT Mon Mar 31 2025

Brief induced ridging into early Monday morning as another
Pacific northwest trough pushes closer. This will open the
Pacific moisture across the CWA as showers will push back in
from the west soon after sunrise into the mid morning hours.
Mountain snow and valley rain expected as the snow level should
remain above the 7000 foot mark. Snow amounts have increased
slightly based on the latest model runs, and as such, have
issued winter weather advisories for the western mountains with
the main impacts being travel over the passes. 4 to 8 inches is
the highest probability of snowfall (50-70%) for these areas 
with the higher amounts confined to the highest terrain up to a 
foot possible (40-50%). 

Heading into Monday afternoon, these showers will push east of
the Divide with mountain snow across the higher terrain and
lower valley rain expected. Limited QPF amounts expected,
though, with only a couple inches of snow for the higher terrain
and less than a tenth of liquid precipitation for lower 
valleys. The most interesting part of the mid to late afternoon 
hours, will be the possibility of localized storm activity 
across southern portions of the CWA for Sweetwater County along 
the I-80 corridor. Some CAPE values up to 100-200 J/kg, 
indicative of this occurrence, albeit low. Regardless, impacts 
will be limited outside of a brief downpour. 

Showers linger into Tuesday, but of less intensity as the trough
axis dips south of the CWA wrapping in the easterly flow for
areas east of the Divide late in the day. Possible very light
snow at that point for the lower terrain with minimal
accumulations possible through the overnight hours. This will
keep the cooler but seasonable temperatures throughout the week
with the main finger of the PFJ well southward across the Desert
Southwest. Very isolated showers possible linger Thursday and
Friday as well but limited in nature as upper level ridging
starts to build in from the west. Slightly warmer Saturday with
the main warming trend Sunday and into early next week as the
aforementioned ridge sets more in place for the upper Rockies.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 444 AM MDT Mon Mar 31 2025

MVFR to VFR conditions across all terminals to start the TAF period. 
KJAC will see precipitation dissipate with a few lingering 
showers possible this morning (20% chance). A brief period of 
showers return to KBPI, KJAC, and KPNA this morning around 15Z 
to 19Z with KJAC seeing showers linger until 01Z Tuesday. KPNA 
and KBPI may see another round of precipitation around 01Z 
Tuesday but at this time due to low confidence PROB30 groups 
have been added. Steadier precipitation is expected to move in 
during the evening with KJAC seeing prevailing light snow 
through 05Z Tuesday. Low ceilings are hanging around terminals 
such as KRIW, KLND, and KCPR this morning with gradual 
improvement expected through the morning. A light breeze is 
expected at most terminals with KCPR, KRKS, and KCOD seeing a 
slight uptick during the afternoon with periodic gusts of 20 to 
25 knots. Convective showers are possible across nearly all 
terminals this afternoon starting around 19Z through around 02Z 
Tuesday. A few rumbles of thunder cannot be ruled out during the
afternoon and evening. KLND, KRIW, and KRKS may see steadier 
precipitation develop around this time continuing to 06Z. KCPR 
sees this precipitation slightly later around 05Z lingering 
through 10Z. Mountain obscuration will be likely through much of
the TAF period. 

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...
Winter Weather Advisory until 6 PM MDT Tuesday for WYZ001-012-
014-024.

&&

$$

DISCUSSION...Lowe
AVIATION...Dziewaltowski