JACKSON, Wyo. – The Tetons have been in a long-duration dry spell since January 10, and aside from some light snow showers on Wednesday, this pattern looks to continue through at least the first week of February, with a warming trend also expected.
Recent Weather
Dry conditions have largely prevailed over the past week, with the only exception being a weak disturbance on Sunday morning that produced 1-3 inches of snow in the Tetons and a dusting in the Jackson Hole Valley.
This minor snow event ended a 14-day dry streak (defined as zero snowfall or less than an inch of new snow) at Jackson Hole Mountain Resort’s Rendezvous Bowl Plot. This was tied for the 6th-longest dry streak on record in the past 50 years, and was the longest dry streak since 2004.
This was nowhere near the longest dry streak on record, however. That belongs to January-February of 1977, when a 36-day dry streak occurred – by far the longest on record.
Aside from the dry conditions, Jackson Hole experienced its coldest stretch of weather so far this winter after catching the western fringe of an arctic cold front last Friday.
This was not an extreme cold snap like we usually see a few times each winter, but we did see three days in a row with temperatures of more than 10 degrees below average in town.
The last time we had a temperature of more than 10 degrees below average in town was on October 28. During this same stretch (since October 28), we have had 38 days with temperatures of at least 10 degrees above average in town. This is using data from the JKNW4 weather station in Jackson.
The coldest temperature during the past week was -9ºF on Monday morning. While -9ºF is still plenty cold, we have yet to record a low of -10ºF or colder in town yet this winter, which is very unusual considering we are nearing the end of January.
Here is a 7-day weather summary for the town of Jackson:
For perspective, the average high and low in Jackson on January 21 are 29º and 7º.
Upcoming Weather Pattern
Unfortunately for skiers and riders, the dry spell is not coming to an end anytime soon. At least not really.
A weak disturbance is moving through on Wednesday, which will bring some snow showers to the area. It’s not a significant event by any means, but the Tetons could pick up anywhere from a trace to 3 inches of new snow, while the valley could see flurries or a light dusting.
Minor winter impacts can be expected for the evening commute over Teton Pass. Also, the west side of the Tetons (Targhee to Teton Valley) will likely see more snow than the east side and Jackson Hole Valley due to more favorable west/northwest winds.
From Thursday to Sunday, high pressure will rebuild over the area, but a series of weak disturbances tracking north of our area will bring periods of cloud cover and will likely prevent a strong inversion from setting up.
Temperatures will warm up at all elevations during this stretch, with valley highs in the mid 30s on Thursday and Friday, before reaching the low 40s on Saturday and Sunday. If an inversion manages to set up, that could potentially lead to colder valley temperatures, but it’s not the favored solution at this time.
On Monday-Tuesday, some models are projecting a weak disturbance to move through with light snow showers or flurries possible. But other models are projecting conditions to stay dry. Confidence is low as a result, but if we do get any snow, it will probably be very light.
The 7-day snowfall projection from the European Ensemble Models shows light snow over the Tetons, with heavier snowfall further north in British Columbia and over the Eastern U.S., most notably in the Carolinas.
Otherwise, mild temperatures will continue into next week, and a further drying trend is expected during the second half of next week as the high pressure ridge over the Western U.S. strengthens and expands northward into Canada, acting as a stronger barrier to storms. This pattern will likely hold through at least February 7.
Is there any hope for a pattern change later in February?
Longer range models are showing some signs that the stagnant weather pattern featuring a strong ridge of high pressure over the West and a deep trough of low pressure over the East (favoring below-average temperatures) could start to shake up some heading into mid-February, potentially opening the door for storms to return, at least on occasion.
NOAA’s 8-14 day outlook still favors below-average precipitation between February 5 and 11, but the dry signal is not as strong compared to before, likely due to some increasing moisture signals in the longer range models toward the end of this period.
Keep in mind that this “possible” pattern shift is nearly 2 weeks away, so confidence is inherently low. But if you’re looking for any signs of hope, then there you have it.
Alan Smith, Meteorologist
