Persistent topographic uplift flow contributed to a prolonged period of mountain snow over the Snowy and Sierra Madre Ranges. Storm total snowfall for several SNOTEL sites in both areas measured over two feet of snow.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS CYS wrote it up.
Persistent topographic uplift flow contributed to a prolonged period of mountain snow over the Snowy and Sierra Madre Ranges. Storm total snowfall for several SNOTEL sites in both areas measured over two feet of snow. The sensor at Med Bow with an elevation of 10,510 feet measured an estimated snowfall total of 43.5 inches.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Cheyenne, WY wrote its last area forecast discussion before the first event at Dec 11, 6:04 PM MST, 2 hours 56 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
2 heavy snow. Local standard time, as filed.
The Old Battle, Whiskey Park, Blackhall Mountain, and Little Snake River sites each measured total snowfall values of over two feet.
The North French Creek and Med Bow Peak sites each measured a total estimated snowfall of over 30 inches. The Sand Lake, Brooklyn Lake, and Cinnabar Park sensors each had estimated snowfall totals over 20 inches.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2019Every state in 2019This day in weather historyWarnings in Wyoming, December 2019
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 864478, 864479.