Frost/Freeze in Central Oregon, Oregon

The ASOS KRDM recorded temperatures at or below 32 degrees for approximately 9 hours ending 0910 PDT. The AWOS KS33 Madras recorded temperatures at or below 32 degrees for approximately 8 hour ending 0855 PDT. The AWOS KBDN recorded temperatures at or below 32 degrees for approximately 7 hours ending 0850 PDT. Most stations in the zone recorded morning low temperatures below 28 degrees.

Increasing northerly flow reinforced by a cold arctic airmass behind a shortwave trough passage starting October 26th lead to temperatures region-wide dropping well below normal. Overnight temperatures across the lower elevations in the intermountain Pacific Northwest were able to cool well below freezing across much the region for much of the overnight period. This lead to all lower elevation zones experiencing their end of season freeze by the morning of October 28th.