Frost/Freeze — Foothills of the Southern Blue Mountains of Oregon, Oregon

2023-10-27 to 2023-10-28 · Foothills of the Southern Blue Mountains of Oregon, Oregon

Event narrative

The AWOS K9S9 Lexington recorded temperatures at or below 32 degrees for approximately 14 hours ending 0955 PDT. The mesonet station CW5615 Heppner recorded temperatures at or below 32 degrees for approximately 15 hours ending 1015 PDT. The mesonet station DW1028 Ajax recorded temperatures at or below 32 degrees for approximately 12 hours ending 1001 PDT. Most stations across the zone recorded morning lows less than 28 degrees.

Wider weather episode

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.

Source: NOAA Storm Events Database, event_id 1145972. Narrative written by the NWS forecast office that issued the report.