Current Conditions and Forecast for Wednesday:

New snow totals as of 5 am were very light, ranging from a trace to an inch in the Tetons. A cold front has just moved through the area in the hours since 5 am and snowfall has picked up along the frontal passage, though snowfall rates still haven't been overly impressive.

Our Weather Stations Map view shows snowfall over the past 24 hours as measured by weather stations across the area.

Notice the higher snow totals north of here in the Madison, Gallatin, and Beartooth Ranges, and to the northeast across the Bighorn Mountains where better moisture and dynamics exist, due to a low pressure center over the Canadian Prairie (moist NW flow wrapping around this feature) and the jet stream setting up over Northern Wyoming.

A wind maximum in the jet stream, known as a jet streak, is nosing its way into Northwest Wyoming. The most favorable regions for vertical motion (which helps to enhance precipitation/snowfall rates) are in the left exit region and right entrance regions of a jet streak, and these favored areas are noted in the purple outlines in the map below. These regions correspond to where the heaviest snow has fallen so far.

The jet stream is slowly working its way southward and we will see a short period of more favorable ascent in the left exit region across the Tetons mid to late morning. 

As a result, snow will continue through the remainder of the morning with the potential for heavier rates for a few hours, though we are still right on the fringe with areas to our east and northeast looking like a better bet for significant snowfall.

By Wednesday afternoon, the jet streak will work its way eastward and we will transition to more of a convective snow shower pattern (moist air rising due to warmer air in the lower levels and colder air at the upper levels of the atmosphere), which will result in more spotty snowfall late in the day.

Lingering snow showers will be possible into early Wednesday evening, before drying out overnight.

Overall, I'm expecting a total of 2-6 inches of snow in the Tetons above 8,000 feet on Wednesday (post 5am reports), including both Targhee and Tetons Pass.

The heaviest snow on Wednesday will fall across the Eastern Absaroka Range and the Bighorn Range. Snowfall will be lighter south of the Tetons in the Salt River, Wyoming, and Wind River Ranges.

Snow-liquid ratios in the Tetons will be around 11:1 (9% density) which I would call medium-density for this time of year. As for skiing conditions, this new snow will likely not cover up old crusts unless we end up with more snow than forecast (typically you need 8+ inches to sufficiently cover old spring crusts, depending on snow density).

However, if you're looking to catch some fresh turn, underlying crusts aside, then Wednesday afternoon and first thing Thursday morning will be your best bet.

Winds on Wednesday will be out of the west/southwest to west/northwest with gusts to 35-45 mph at 10,000 feet. Note that the tram weather station is down as of this writing on Wednesday AM, and I'm not sure when it will be restored.

The Mt. Glory weather station also records wind speeds and gusts, though usually, the reported winds are lighter at that station versus the top of the tram. Same goes for Fred's Mountain at the top of Targhee.

As for the valley, snow is falling on Wednesday AM but temperatures are above freezing so the snow is not accumulating, at least in the town of Jackson. Minimal to no accumulations are expected down low.

Forecast for Thursday:

Conditions will dry out with mostly sunny to partly cloudy skies, but a chilly airmass will linger with morning lows in the teens and afternoon highs ranging from the upper 20s (9,000 feet) to low 40s (valleys). Winds will be out of the west with afternoon gusts of 15-20 mph at 10,000 feet.

Forecast for Friday:

A hard freeze is expected in the morning with lows in the upper teens at all elevations, then we will transition into a warmer pattern with highs reaching the mid 30s at 9,000 feet and near 50 in the valleys under mostly sunny to partly cloudy skies.

A transition back to spring skiing can be expected by Friday afternoon with softening occurring on most slopes.

Winds will be relatively light out of the west/southwest with gusts to 10-15 mph at 10,000 feet in the afternoon.

Forecast for Friday Night to Saturday:

A weak disturbance will pass to our north and east overnight, resulting in just a slight chance of showers on Friday night and into Saturday morning. 

This disturbance will not do much to slow down our warming trend as we will see highs ranging from near 40 (9,000 feet) to the mid 50s (valleys) on Saturday afternoon.

Winds will pick up a bit out of the west/southwest with gusts to 20-25 mph at 10,000 feet.

Forecast for Sunday (Targhee Closing Day):

A mild but unsettled pattern can be expected as a disturbance passes just north of our area. The result will be a mix of sun and clouds along with a decent chance of showers, especially during the afternoon.

Temperatures will remain on the warmer side, however, with snow levels ranging from 8,000 to 9,000 feet. This does not look like a significant event by any means, with any showers expected to be light and spotty.

Unfortunately, winds are expected to become strong on Sunday afternoon with gusts to 40+ mph possible up high.

As a result, Saturday looks like the nicer day for spring skiing this weekend, with conditions a little more unsettled for the final day at Targhee on Sunday. But we'll revisit this on Friday once we have a better idea of how things are looking. 

Early next week (April 22-25), I'm expecting more of the same with mild spring temperatures, even warmer than prior days, along with occasional clouds and isolated showers. Given the warm pattern and the time of year, any showers will most likely be convective in nature and confined to the afternoon hours.

Late next week (April 26-28), I'm seeing some signs of a more unsettled and possibly wetter pattern with a higher chance of showers compared to earlier in the week. However, temperatures are expected to stay fairly mild (perhaps some slight cooling) which would likely result in rain showers in the valleys and snow showers up high.

Thanks so much for reading!

Moving forward, I'll post a Targhee closing weekend outlook this Friday (April 19) along with a winter season recap for the Tetons.

After that, I'll be taking some time off for the rest of April, then will resume forecasts in early May.

Alan Smith 

Summer Weather: How To Use OpenSnow

As the snow begins to melt and summer conditions quickly take over, remember that you can use OpenSnow as your go-to weather app during the non-winter months.

Get started by going to...

1. Favorites > Weather
2. Location > Weather
3. Maps > Weather

Switch to using your "Summer" favorites list, check the "Weather" tab on both the Favorites screen and any location screen, and avoid poor air quality & incoming storms with our summer-focused map layers in the OpenSnow app.

You can also view the hourly forecast for the next 10 days for any location on Earth in OpenSnow.

1. Go to the "Maps" tab.
2. Tap anywhere or search for a city.
3. Tap "View Forecast".

View → Summer Forecasts

Important Dates:

Snow King – CLOSED for the season (open for uphill access)

Jackson Hole Mountain Resort – CLOSED for the season (no uphill access)

Grand Targhee – Closing Day April 21

Grand Teton Park Road – Open for bike and foot traffic, closed to cars until May 1

Static Peak and Other Winter Wildlife Closures – in effect until May 1