Colorado, 2020

Heavy Snow in Colorado, December 10 to 12, 2020

December 10 to 12, 2020 · NWS PUB · 2 events in 2 counties and zones

An upper level system moved across the region during this period, and provided widespread accumulating snow to southern Colorado. Many snowfall reports under six inches were observed, however, a few reports of heavier snow occurred closer to the Colorado and New Mexico border.

Where it happened

Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
2

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.

What happened

The episode as NWS PUB wrote it up.

An upper level system moved across the region during this period, and provided widespread accumulating snow to southern Colorado. Many snowfall reports under six inches were observed, however, a few reports of heavier snow occurred closer to the Colorado and New Mexico border.

What forecasters said that day

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 Pueblo, CO wrote its last area forecast discussion before the first event at Dec 10, 7:50 PM MST, 1 hour 10 minutes earlier.

Area forecast discussion, Dec 10, 7:50 PM MST, 1 hour 10 minutes before
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The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

2 heavy snow. Local standard time, as filed.

Heavy Snow, Southern San Luis Valley

When
December 10, 9:00 PM MST to December 11, 6:00 AM MST
Where
Southern San Luis Valley forecast zone
Reported by
Trained Spotter
Coordinates
37.240, -105.810 (the zone’s center; the record gives no point)

Heavy snow of 8.5 inches. 2 east Fort Garland.

Heavy Snow, Eastern San Juan Mountains Above 10000 Ft

When
December 11, 2:00 AM MST to December 12, 6:20 AM MST
Where
Eastern San Juan Mountains Above 10000 Ft forecast zone
Reported by
Public
Coordinates
37.484, -106.500 (the zone’s center; the record gives no point)

Heavy snow of 15.0 inches. 1 southeast Wolf Creek Pass.

What these are

Heavy Snow
Snowfall reaching the local warning threshold without the other hazards of a winter storm.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Colorado in 2020Every state in 2020This day in weather historyWarnings in Colorado, December 2020

Sources

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 2026-09-30. Each event’s entry at NCEI: 935678, 935679.