Strong flow aloft coupled with Pacific moisture produced a prolonged period of moderate to heavy snow for the north central mountains. The heaviest snowfall occurred in the mountains north of Interstate 70.
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.
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 BOU wrote it up.
Strong flow aloft coupled with Pacific moisture produced a prolonged period of moderate to heavy snow for the north central mountains. The heaviest snowfall occurred in the mountains north of Interstate 70. Storm totals included: 27 inches at Tower, 18 inches at Zirkel, 13 inches at Deadman Hill, 12 inches at Arapahoe Ridge and Lake Irene, 11 inches at Long Draw Reservoir, with 10 inches at Never Summer and Willow Park.
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 Denver/Boulder, CO wrote its last area forecast discussion before the first event at Nov 4, 2:28 PM MST, 2 hours 32 minutes earlier.
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</html>Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1023 AM MDT Sat Nov 4 2017 COZ030>051-051630- 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- 1023 AM MDT Sat Nov 4 2017 ...High Wind Warning for the Palmer Divide through 3 pm this afternoon... ...Winter Storm Warning Tonight through Sunday Night in the northern Mountains... This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...Today and Tonight Very warm and breezy conditions are expected today across the northeast plains as strong southwesterly flow aloft covers Colorado. The combination of warm temperatures and gusty winds will elevate fire danger levels across the plains. Winds are expected to be strongest over the Palmer Divide. Winds of 35 to 45 MPH with gusts of 60 to 70 MPH may cause travel problems due to strong crosswinds and low visibilities in blowing dust. The strong winds may also knock over some trees and branches. Winds are expected to decrease late in the afternoon. In the mountains, light snow and icy roads will can be expected over the higher mountain passes this afternoon, with mild and windy conditions below 10 thousand feet. Tonight, temperatures will cool with lowering snow levels. Snow will be heavy at times over the Rabbit Ears and Gore Ranges. Heavy snow will also be possible in the mountains of Grand and Larimer Counties. Five to 10 inches of snow will be possible over the northern mountains. Less snow is expected over the mountains of Summit County with 3 to 6 inches of snow possible. .DAYS TWO THROUGH SEVEN...Sunday through Friday Periods of moderate to heavy snow will continue in the higher mountains through Sunday night and then begin to decrease on Monday. The heaviest snowfall will be north of Interstate 70, along west and southwest facing slopes. Storm totals by late Sunday night of 8 to 16 inches with locally up to 24 inches inches will be possible. There may be some rain mixed with snow showers in the mountain valleys as well with light snow accumulations. For Monday night through Tuesday another weather system will bring another good chance of snow to the mountains. There will also be a good chance of showers on the plains which will turn to snow late Monday night into Tuesday. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed today or tonight.
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</html>The national radar mosaic for the moment the first event began.
2 heavy snow. Local standard time, as filed.
Storm totals included 27 inches at Tower with 18 inches at Zirkel.
Storm totals included: 13 inches at Deadman Hill, 12 inches at Arapahoe Ridge and Lake Irene, 11 inches at Long Draw Reservoir, with 10 inches at Never Summer and Willow Park. .
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2017Every state in 2017This day in weather historyWarnings in Colorado, November 2017
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: 726033, 726034.