Mountain Waves Bring 100mph+ Winds To North

The National Weather Service
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Strong westerly flow across the northern mountains resulted in some breaking mountain wave action across some foothill locations last night. The most impressive of these lee-side mountain waves occurred at Clark West, where gusts exceeded 80mph for almost 2 1/2 hours, peaking at an amazing 104mph at 11:20pm late Tuesday night! Mountain waves were visible on satellite, most notably on water vapor satellite, where the downslope drying was evident along the lee side of each mountain range, with wave-generated crest clouds showing up a bit further downstream of the downslope drying.

Click to enlarge Click to enlarge loop.

Click Image to Enlarge

The schematic above depicts what happens to the air flow during a mountain wave scenario. Air flowing across a mountain chain interacts with the stable air on the lee side of the mountains, forcing the air downward, sending it crashing into the ground. Mountain waves are often visible on satellite because clouds form at the crest of each wave, while the trough of the wave sends accelerated, warmer air crashing to the ground. 

Click Loop to Enlarge

A mountain wave was visible on satellite overnight. The loop above shows the infrared satellite image between 745pm Tue through 1230am Wed.


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Wind Map - Click to enlarge
Strongest Winds Tuesday Night - early Wednesday 
County Station Name (Elevation)
Wind Gust (mph)
Park 5 WNW Clark (4659')
Park Hoyt Peak (9800') 65
Johnson 12 N Kaycee (5287')
7 SW Barnum (6440')
Natrona Casper - Outer Drive (5495')
Lincoln Mt. Coffin (10870')
Natrona 16 S Hiland (6380') 56
Chief Joseph Highway (8136')
Fremont 7 SW Muddy Gap (7380')
Teton Jackson Hole Mtn Resort - Summit
Park 1 W Clark (4270')
Park 10 WNW Cody (8401')
Fremont 10 W Fort Washakie (9235')
Hot Springs
Boysen Peak (7300')
Park 8 S Clark (4710')
Fremont Beaver Rim (6784')
2 NW Mayoworth (5404')




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