Winter tire dates for Seattle
Computed from the 30-year climate record at Seattle Boeing Fld, the official NOAA station 7 km from Seattle, Washington.
All-day events with a one-week reminder, straight from this page.
The climate record behind these dates
Mean daily temperature by month at Seattle Boeing Fld, 30-year normals. The tire windows fall where this line crosses 45F.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 43 | 44 | 47 | 52 | 58 | 63 | 67 | 68 | 63 | 54 | 46 | 42 |
Values below 45F shown in blue: winter tire season at Seattle.
Winter tires and the law
No state or federal mandate
The United States has no winter-tire law: the dates above are a climate recommendation, not a legal requirement. A few mountain states enforce seasonal traction or chain requirements on specific highways and passes during winter storms. Those are road- and condition-specific, so check your state department of transportation before mountain travel in winter.
Seattle winter tire questions
When should winter tires go on in Seattle?
Around November 28. That is when the mean daily temperature at Seattle Boeing Fld, the official station nearest Seattle, historically settles below 45F, the threshold where winter compounds outgrip all-seasons even on dry pavement. Book the swap a week or two ahead; shops fill up after the first cold snap.
When do winter tires come off in Seattle?
After February 22, when mean daily temperatures climb back above 45F to stay. Taking them off earlier risks a late cold snap; much later wears the soft compound on warm pavement.
Are winter tires required by law near Seattle?
There is no federal winter-tire law in the United States, and most states do not mandate them. A handful of mountain states enforce seasonal traction or chain requirements on specific highways and passes during winter storms. Those are road- and condition-specific, not a blanket rule for your city, so check your state department of transportation before mountain travel.
How are these dates calculated?
From NOAA NCEI U.S. Climate Normals 30-year climate normals at Seattle Boeing Fld (7 km from Seattle): monthly mean daily temperatures anchored mid-month, linearly interpolated across the 45F threshold. They are planning averages from the official record, not forecasts. Full method on the methodology page.
How this page was made
The dates above are computed, not written: monthly mean daily temperatures from the NOAA NCEI U.S. Climate Normals at Seattle Boeing Fld, interpolated across the 45F tire-compound threshold. Full method: data and methodology. These are planning averages from the official record, not forecasts: microclimates, valleys, and lakeshores can run a week off the station record. Watch the forecast in the shoulder weeks before acting.
More for Seattle: frost and planting dates. Different place? The full planner covers all 2697 stations.