Frost/Freeze in Simcoe Highlands, Washington

The mesonet station EW0859 Centerville recorded temperatures at or below 32 degrees for approximately 14 hours ending at 1000 PDT. The mesonet station EW1633 Lyle recorded temperatures at or below 32 degrees for approximately 14 hours ending at 0930 PDT. The RAWS site HIBW1 recorded temperatures at or below 32 degrees for approximately 11 hours ending at 0856 PDT. The RAWS site GNLW1 recorded temperatures at or below 32 degrees for approximately 13 hours ending at 0809 PDT.

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 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.