John McGinley, Peak to Peak.

October 2020: A hellish month by any measure brought on by months of below normal precipitation and a jet stream pattern that set us up for 11 days of exceedingly dry, warm, and windy weather. This resulted in major fires breaking out in Boulder, Larimer, and Grand counties destroying hundreds of homes and property. Between the 11th and 22nd we had gusts to over 50 mph nearly every day. This caused unprecedented rapid spread of the fires. Folks in southern Boulder and Gilpin counties were on pins and needles, expecting to see a new smoke plume to the west. Temporary salvation came in the form of an upper level wave that brought over a foot of snow to the area, stopping the fire spread and allowing firefighters to gain the upper hand. We can’t give enough praise to the air and ground teams who bravely fought these monsters.

Precipitation: After a slow start that gave us a few hundredths of an inch, an arctic front from the 22nd to the 26th allowed us to recover with 13.5 inches of snow, melting out to 0.81 inches of liquid. This brought the snow total for the month to be above the average of 11 inches. Normal water equivalent for October is 1.26 inches so we were a bit below normal

Temperature:  The first half of the month was 10 degrees above normal with low relative humidity. After the arctic air moved in temperatures plummeted to below zero. By the time we reached the end of the month our average temperature was only a few degrees above normal.  Average high was 55F with a low of 30F. These combined to make us 2 degrees warmer for the month. Highest high was 71F on the 8th; lowest high was 13F on the 26th. Coldest low was -3F on the 26th. 

Winds:  A record number of windy (40+ mph) days this October with 15. Peak wind was 70mph on the 24th.

Other Features: More ridge conditions to our west brought strong Jetstream winds out of the northwest. This created an intense low level pressure trough to our east that supported day after day of strong downslope winds.

Outlook for November:  Big changes afoot as we will see the breakdown of the ridge allowing cold polar air to move into the Rockies and bringing multiple storms with the likelihood of cold and snow.  We should see disturbances on the 8th and 12th. After that cool temperatures will prevail with normal precipitation. Late in the month it looks warm and dry. Average high/low for November is 42F/21F. We typically see about 18 inches of snow melting out to 1.13 inches of liquid. We normally have 11 windy days with 3 days over 60mph.