Alert archive / Colorado / Snow Squall Warnings in 2020
Snow Squall Warning 11, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this snow squall warning at Mar 1, 2020, 9:10 PM MST for Boulder County, Larimer County, Weld County, Colorado. It was in force for 50 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Mar 1, 2020, 9:10 PM MST (04:10 UTC)
- Expired
- Mar 1, 2020, 10:00 PM MST
- In force
- 50 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
Counties Boulder County, CO, Larimer County, CO, Weld County, CO
The radar
The Cheyenne radar (KCYS), 82 km from the middle of the area, began a volume at 04:09 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Denver, CO (KDNR), launched 00:00Z, 4.2 hours before the alert went out and 169 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 911 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 142 m²/s²
- 0-3 km storm-relative helicity
- 363 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
What forecasters said that day
The local office's own words before this snow squall warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Denver/Boulder, CO wrote its last area forecast discussion before this snow squall warning went out at Mar 1, 9:08 PM MST, 2 minutes earlier.
Area forecast discussion, Mar 1, 9:08 PM MST, 2 minutes before
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</html>Hazardous weather outlook, Mar 1, 10:32 AM MST, 10 hours 38 minutes before
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1032 AM MST Sun Mar 1 2020 COZ030>051-021745- Jackson County Below 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- Grand and Summit Counties Below 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet- Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear Creek/Northeast Park Counties Below 9000 Feet- Central and Southeast Park County- Larimer County Below 6000 Feet/Northwest Weld County- Boulder And Jefferson Counties Below 6000 Feet/West Broomfield County- North Douglas County Below 6000 Feet/Denver/West Adams and Arapahoe Counties/East Broomfield County- Elbert/Central and East Douglas Counties Above 6000 Feet- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 1032 AM MST Sun Mar 1 2020 ...WINTER WEATHER ADVISORY TONIGHT FOR THE MOUNTAINS, FOOTHILLS, PORTIONS OF THE ADJACENT PLAINS AND PALMER DIVIDE... This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...Today and Tonight A storm system will bring a period of snowfall to the mountains and foothills this afternoon and evening, then decrease after midnight. In the mountains storm totals will range from 3 to 9 inches, possibly heavy at times later this afternoon and evening. Across the urban corridor and northeast plains, a cold front will push into the area from the northeast this afternoon. A mix of rain and snow late this afternoon will change over to snow by this evening. Snow could be heavy this evening with snowfall rates up to 2 inch per hour, especially from Denver southward. The snow should start to taper off after midnight. Storm totals will range from 1 to 4 inches, with locally higher amounts possible near the foothills and over the Palmer Divide. .DAYS TWO THROUGH SEVEN...Monday through Saturday Areas of snow will continue in the mountains Monday morning with up to 2 inches of additional snowfall. For the Front Range and eastern plains, light snow may linger into the early morning hours, though should be done by 8 AM. Patchy fog will also be possible Monday morning. For Tuesday through Saturday, a dry and mild pattern will prevail, with a couple dry frontal passages expected. This may start to increase fire weather concerns across the plains depending on how much snow is received tonight into Monday. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed today or tonight. However reports of heavy snowfall will be appreciated.
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 1, 6:12 PM MST | Snow Squall Warning | BOU | Larimer | 63 min |
| Mar 1, 6:38 PM MST | Snow Squall Warning | BOU | Larimer, Weld | 52 min |
Nearby
Snow Squall Warnings in Colorado, 2020Every snow squall warning in 2020
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.