3 of 5 stations freeze at 2 inches in a typical winter, 1 of them to 8 inches or deeper.
Station by station
Each bar runs from the typical first freeze to the typical last thaw at that depth, the median over the station's complete winters on record, with the typical number of frozen days after it. Frost reaches the deeper probes later in the winter. A depth that froze in fewer than half of its winters has no typical dates. Stations: 3 typically freeze, 2 froze in some winters.
Typically freezes to 2 inches, not to 4.
Froze at 2 inches in 2 of 4 complete winters on record.
2 in: froze in 2 of 4 · 4 in: froze in 1 of 4 · 8 in: froze in 0 of 4 · 20 in: froze in 0 of 4 · 40 in: froze in 0 of 4
Typically freezes to 8 inches, not to 20.
Froze at 2 inches in 1 of 4 complete winters on record.
2 in: froze in 1 of 4 · 4 in: froze in 0 of 4
Typically freezes to 2 inches, not to 4.
A winter runs July to June. Our station readings come from one grass-covered site per station at five fixed depths, and often show shallower frost than regional figures.
Where the ground is frozen today across the US · Washington soil temperature · First frost and frost depth guide