Best days to seal a driveway in Seattle, WA this week
Here's the next 7 days for sealcoating a driveway in Seattle, checked hour by hour against the published thresholds. Below it: what Seattle's 1991–2020 climate averages say about the months that usually work.
This week in Seattle
Asking the sky…
Fairsky is not a substitute for official warnings. For warnings, go to weather.gov. Verdicts are guidance, not guarantees. Your product's label always wins.
When sealcoating a driveway usually works in Seattle
- On 1991–2020 averages, Seattle has normal highs of 55°F or warmer with normal lows of 50°F or warmer, the temperatures driveway sealer needs day and night, in June–September.
- Of those months, July averages the fewest days with 0.10" or more of rain (1.3), which matters because sealer needs about 36 rain-free hours to cure.
- In April–May and October, afternoons are warm enough but normal lows drop below 50°F, so the sealer may not cure overnight.
| Month | Avg high | Avg low | Days ≥0.10" rain | Highs 55–95°F, lows 50°F+ |
|---|---|---|---|---|
| January | 49° | 37° | 12.1 | – |
| February | 51° | 37° | 9.0 | – |
| March | 55° | 39° | 10.5 | – |
| April | 60° | 44° | 8.0 | – |
| May | 67° | 49° | 5.6 | – |
| June | 71° | 54° | 3.6 | Yes |
| July | 77° | 58° | 1.3 | Yes |
| August | 77° | 58° | 1.8 | Yes |
| September | 72° | 54° | 3.8 | Yes |
| October | 61° | 46° | 7.8 | – |
| November | 53° | 40° | 11.3 | – |
| December | 48° | 36° | 11.4 | – |
Station: Seattle Boeing Fld (NOAA NCEI USW00024234), about 9 km from central Seattle. “Rain days” count days with 0.10" or more of precipitation. “Highs 55–95°F, lows 50°F+” checks the monthly averages only; any given week can be warmer, colder or wetter.
The rules we check
- Needs 3 hours in a row of daylight.
- Air at least 55°F (50–54°F is borderline).
- No hotter than 95°F. (Fairsky default: no source gave a number)
- Rain chance at or below 10%. (Fairsky default: no source gave a number)
- No rain in the 12 hours before, so surfaces are dry. (Fairsky default: no source gave a number)
- No rain for 36 hours after you finish.
- The first night's low stays at 50°F or warmer.
Your product's label always wins. Labels differ by product; in the app you can enter your label's temperature range and rain-free hours, and the verdict uses them instead.
Sources: SealMaster sealcoating FAQ
More home and yard jobs in Seattle
- Stain a deckDeck and fence stain: 50–90°F, dry wood, 24 rain-free hours after.
- Paint a house exteriorExterior latex paint: 40°F and up, 5°F above the dew point, 4 dry hours after.
- Pour concreteConcrete: 40–85°F, no rain for 24 hours, no freezing for 48.
- Spray weedsWeed killer: 3–10 mph wind, 45–85°F, 4 rain-free hours after.
- Apply pre-emergentCrabgrass pre-emergent: before soil holds 55°F (about 200 GDD), then water it in.
- Plant grass seedCool-season grass seed: soil about 50–65°F, highs 60–80°F, no washout rain.
- Cover plants for frostFrost watch: cover at 34°F, or 36°F on clear, calm nights; 28°F is a hard freeze.
The app covers 47 activities in all, from mowing to a round of golf: see every activity and its rules.
Seal a driveway in nearby cities
- Portland, OR145 miles away
- Spokane, WA228 miles away
- Boise, ID405 miles away
- Sacramento, CA625 miles away
- Stockton, CA669 miles away
- Ogden, UT674 miles away
All seal a driveway cities: Seal a driveway, by city · Home and yard in Washington
Questions
What's the best month to seal a driveway in Seattle?
On 1991–2020 averages, July usually fits best in Seattle. Any given week can still be wrong for it, which is what the live verdict above is for.
How is this verdict made?
We take the National Weather Service hourly forecast for Seattle and check each hour against the thresholds listed above. The result is guidance, not a guarantee; your product's label always wins.
When can I seal my driveway in Seattle?
Most sealcoat asks for 50–55°F and rising, a warm night after, and 24–36 rain-free hours. The verdict above looks for that stretch in Seattle.
Fairsky is not a substitute for official warnings. For warnings, go to weather.gov.
Live forecasts: National Weather Service / NOAA (public domain), fetched by your browser. Climate averages: NOAA NCEI U.S. Climate Normals, 1991–2020 (public domain). Activity thresholds: product data sheets, ACI and university extension guidance, linked on each page; your product’s label wins.