A Sneaky Situation that Drops Almost Two Feet of Powder

This February has been nicknamed Stormuary by some of the locals in Jackson Hole. Storms keep rolling in one after another. The weather has been unrelenting, dropping copious amounts of powder practically every day.

After three weeks of snow, to top it off, on February 23rd, we received 19” in 24 hours with 15” falling after the lifts closed. To say it was deep was an understatement.  Local meteorologist, Jim Woodmency is the most widely respected snow forecaster in the valley, but this storm had him scratching his head for explanations. After thinking about it, this was his analysis of the “sneaky situation” that caused the deepest day of the year. With photos from the day of course.
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Words: Jim Woodmencey: I figured it out…..why so much on this side of the hill Saturday evening…..and similar situation to the Bridger-Bowl-Cloud phenomena….moderate and consistent WNW to NW flow aloft (@ 10,000-ft)…less than 30 mph. And a light but consistent SE flow in the valley, 10 to 15 mph (from JH Airport obs).
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We get the orographic lift over the Teton mountains in a perpendicular direction aloft (WNW), AND we also get a low-level flow that is pushing back up against the mountains from the SE, down at lower elevations. Essentially getting a convergence of the lifting, and causing the clouds to “stand-still” over JHMR, and keep puking!

We also had a weak surface Low pressure center right over us and a stationary front, both adding additional lift and instability to the atmosphere, and producing about 3 inches in town.
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At the same time on the other side of the hill at Targhee, they had the orographic lift aloft with a WNW flow, but they also had the same SE wind at the Driggs airport, which pulls air down off the mountains, rather than pushing it back up the face, kind of negating the orographic lift a bit.
G day
Indeed a sneaky situation that would be hard to forecast for much ahead of time.
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