The building maintenance scheduled for Friday February 27th at 5:00pm MST has been postponed until 5:00pm March 6th. PSD's website will be down during the maintenance.
First Day of Frost in Boulder
Data from 1957-1995
Frost is defined here as the minimum temperature being less than or equal to 32 F. Frost may occur even when the official temperature is above 32F as the ground can be colder than where the thermometer is located (typically 3 meters above the surface).
earliest day of frost: Sep 12 (1974) latest day: Oct 31 (1963) average: Oct 6 first quartile Sep 25 median Oct 5 third quartile Oct 18 standard deviation 13.6 days