A storm system is poised to set up and stall along the Nevada-Utah border on Tuesday but the main impacts continue to trend to our north as shown in the liquid precipitation forecasts of the GFS (more bullish) and European (less bullish) Ensembles through Thursday.

For New Mexico, we could still see a few inches of snow above 10,000 feet on Tuesday and Wednesday favoring the most northern Sangres. 

The Taos Avalanche Center posted a final end-of-season discussion looking at what to expect in the days and weeks ahead, if heading out into the backcountry, with rapid snowmelt and a few doses of cold and new snow in April. 

A colder system that could bring overnight temperatures back into the teens above 10,000 feet looks possible for April 17-19 which I cover in the extended forecast below.

Winter storm setups for Pajarito

As part of the season wrap-up, I asked readers if there were topics or questions they would like me to cover and one reader asked what are the optimal setups for Pajarito to receive good snowfall. This is a great question because for me Pajarito is often a conundrum for snow forecasting. 

First, the history of Pajarito is quite fascinating as it was first identified for skiing in 1943 by a group of mostly European Los Alamos scientists and soldiers who grew up climbing and skiing the Alps and were hungry for a taste of home here in New Mexico. You can read more about the history in this Ski Magazine article.

They chose Pajarito's current site for its proximity to Los Alamos, the relatively steep terrain, and the north-facing aspect that could best preserve the modest average of 150" of annual snow through winter.

But Pajarito's position on the northeast side of the Jemez Mountains at a modest average elevation of 10,000ft, with the larger San Juan Mountains to the north and northwest, and the larger Sangre de Cristos to the east, means that Pajarito requires fairly nuanced setups for deeper double-digit storm totals. 

In New Mexico, most winter storms approach from the west, southwest, and northwest. And since Pajarito is on the northeast side of the Jemez Mountains, it can sometimes struggle with being on the rain-shadow side. So winds from the southwest, west, or northwest could produce more snow on the other sides of the Jemez and less where Pajarito lies if the storm energy isn't strong enough. On the flip side, winds from the south or southeast have an unobstructed path to Pajarito which we discuss more below.

One of the more common setups that we see is the classic Four Corners storm where a storm's center of circulation tracks over the Four Corners and brings southwest winds and often a surge of subtropical moisture near Pajarito. 

Every time this setup happens I want to believe that Pajarito will do well but almost every time what really happens is that Wolf Creek gets 2 to 3 feet, the Tusas Mountains around Chama get 12-16", and Pajarito only gets 6". In most cases, the classic cut-off Four Corners low is not optimal for Pajarito because the southwest winds have an unobstructed path to the San Juan Mountains and either miss Pajarito to the west, or impact the west side of the Jemez more and leave Pajarito in the relative rain shadow. 

I looked back at some of the more recent big storms for Pajarito and I see two optimal setups for deep totals. 

1) Southern trough with main jet stream overhead. When the main winter jet stream dips south and forms a trough bringing cold arctic air that also pulls up sub-tropical moisture, this can produce northeast angled heavy snow bands and Pajarito is often situated well for these setups. 

The jet stream energy is strong enough that rain shadow is not a factor. This happened with the January 19, 2021 storm that delivered 12" and enough for Pajarito to open for the season. 

Here is the graphic of the upper-level winds for the January 19th storm where I discussed the jet stream as a main driver of snow and where this lined up could produce heavy snow bands. The pink arrow over the Jemez shows why Pajarito can do well with this setup.

Here is a radar shot of that storm showing moisture surging up from the south, and the line of deep blue is the heavy snow band where the jet stream is overhead and it is lined up perfectly over Pajarito. 

This setup is different from the cut-off low over Four Corners discussed above that produces its own southwest winds, but doesn't have the main jet stream energy. With these cut-off lows, the main jet stream is usually somewhere far to the north.

1) Cut-off storm that tracks across central or southern New Mexico bringing south and southeast winds to Pajarito. 

While most cut-off storms tend to track across the Four Corners, every season a few of these storms take more of an eastern track across central New Mexico with the center of circulation to the south of Pajarito.

This produces south and southeastern winds which have an unobstructed path to Pajarito and the 10,400-foot summit can produce good orographic lift and heavy snowfall. We saw this setup with the March 23-24, 2021 storm where Pajarito picked up 12-14".

Here is the radar on the morning of March 24th showing the center of circulation near Socorro and a steady flow of snow showers moving from the southeast to northwest into Pajarito.

Let's hope the 2021-2022 season brings many of these two good setups for Pajarito.

Turning back to the current forecast, from April 16 to 19 colder temperatures are forecast to push across the eastern half of the state, giving a little taste of winter with high elevation temperatures in the teens and twenties. The greens and blues in the map below are 7 to 13 degrees F below normal.

And in this same timeframe of April 17-19, we could see decent precipitation for New Mexico as the GFS Ensemble continues to signal above-average liquid precip for much of the Land of Enchantment.

This upcoming week I will post a few more discussions of topics requested by readers, including a scan of season snowfall totals at different resorts (where available), and then a final wrap-up post looking at memorable storms and moments from the 2020-2021 season.

Not too late to hit me up with any topic/question requests.

JULIEN ROSS
[email protected] 

New Mexico Geography Key

Northern Mountains
→ Red River, Taos Ski Valley, Angel Fire (north side of northern mountains - Sangre de Cristos)
→ Sipapu (middle of the northern mountains - Sangre de Cristos)
→ Ski Santa Fe (south side of the northern mountains - Sangre de Cristos)
→ Pajarito (southwest side of the northern mountains - Jemez)

Central Mountains
→ Sandia Peak (Sandias)
→ Mt. Taylor backcountry (San Mateos)

Southern Mountains
→ Ski Apache (Sacramentos)
→ Ski Cloudcroft (Sacramentos)