# Frost dates for Hillsboro, OR (97123)

**Do this (Safe, 2026-11-02):** Frost season started Oct 3. Keep covers ready for cold nights.

| Risk | Last spring frost | First fall frost | Frost-free days |
|---|---|---|---|
| Safe (1 in 10 years later) | May 3 | Oct 3 | 153 |
| Median | Apr 16 | Oct 23 | 190 |
| Bold (9 in 10 years later) | Mar 25 | Nov 18 | 238 |

Frost = 32°F. Station: Portland-hillsboro AP, OR, 1 mi away.

## Next nights (NWS overnight low)

- 2026-11-01: 35°F — Cover (tonight)
- 2026-11-02: 43°F — Go
- 2026-11-03: 38°F — Wait
- 2026-11-04: 44°F — Go
- 2026-11-05: 44°F — Go
- 2026-11-06: 41°F — Go
- 2026-11-07: 44°F — Go

Go above 40°F · Wait 37–40°F · Cover 36°F or less · Freeze 28°F or less.

Source: Frost dates: NOAA NCEI U.S. Climate Normals 1991–2020, station Portland-hillsboro AP, OR (1 mi, about your height). Not endorsed by NOAA. Nights: National Weather Service.

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