Sealcoating
Oregon Sealcoating Season: When the Window Opens and Closes
Cojo
March 19, 2026
6 min read
Oregon has one of the shortest sealcoating seasons in the contiguous United States. While contractors in Arizona or Texas can sealcoat nearly year-round, Oregon's combination of heavy rainfall and cool temperatures compresses the viable window into roughly 3.5 months: mid-June through September.
Understanding exactly when the window opens, peaks, and closes in your part of Oregon is the difference between a successful project and a wasted investment.
These months are categorically unsuitable for sealcoating anywhere in Oregon. Average rainfall ranges from 3 to 6 inches per month. Temperatures are well below the 50°F minimum. Do not schedule, do not attempt, do not accept a bid from any contractor willing to apply sealcoat during these months.
What to do instead: Use winter months for planning. Get condition assessments, request bids, and confirm scheduling for the upcoming season. Contractors who book during winter months are rewarded with better pricing and priority scheduling.
May brings improving conditions but remains unreliable.
| Region | Avg High | Avg Low | Rainfall | Viability |
|---|---|---|---|---|
| Eugene/Springfield | 66°F | 45°F | 2.3" | Late May only, dry years |
| Corvallis/Albany | 65°F | 44°F | 2.5" | Late May only, dry years |
| Salem/Keizer | 64°F | 43°F | 2.5" | Late May only, dry years |
| Oregon Coast | 59°F | 46°F | 3.0" | Not viable |
For strategies on early-season work, see our spring sealcoating in Oregon guide.
By mid-June, Oregon's dry season takes hold. The transition typically happens between June 10 and June 20 — there is almost always a noticeable shift from spring rain patterns to summer dryness.
| Region | Avg High | Avg Low | Rainfall | Viability |
|---|---|---|---|---|
| Eugene/Springfield | 73°F | 50°F | 1.3" | Good from mid-June |
| Corvallis/Albany | 72°F | 49°F | 1.5" | Good from mid-June |
| Salem/Keizer | 72°F | 49°F | 1.5" | Good from mid-June |
| Oregon Coast | 63°F | 51°F | 1.8" | Fair from late June |
Risk factor: Overnight lows hover right at the 50°F threshold in June. Monitor closely. One cool night can compromise a cure.
July is one of the two best months for sealcoating anywhere in Oregon. Portland averages just 0.5 inches of rain for the entire month. Eugene is similar. Extended dry stretches of 10 to 14 consecutive days are normal.
| Region | Avg High | Avg Low | Rainfall | Viability |
|---|---|---|---|---|
| Eugene/Springfield | 82°F | 53°F | 0.3" | Excellent |
| Corvallis/Albany | 80°F | 52°F | 0.4" | Excellent |
| Salem/Keizer | 81°F | 53°F | 0.5" | Excellent |
| Oregon Coast | 66°F | 53°F | 0.7" | Good |
Booking reality: July dates book fast. Most contractors are fully scheduled for July by mid-May. If July is your target, get your bid and confirmation done by April.
August mirrors July with the driest conditions of the year. This is the last month of guaranteed excellent conditions.
| Region | Avg High | Avg Low | Rainfall | Viability |
|---|---|---|---|---|
| Eugene/Springfield | 82°F | 53°F | 0.4" | Excellent |
| Corvallis/Albany | 81°F | 52°F | 0.5" | Excellent |
| Salem/Keizer | 81°F | 53°F | 0.5" | Excellent |
| Oregon Coast | 66°F | 53°F | 0.8" | Good |
September is a transition month. Early September still offers summer-like conditions. Late September increasingly resembles fall.
| Period | Avg High | Avg Low | Rainfall | Viability |
|---|---|---|---|---|
| Sept 1–15 (all regions) | 76°F | 50°F | 0.5" | Good |
| Sept 16–30 (all regions) | 70°F | 47°F | 1.5" | Fair — watch lows |
| Oregon Coast (all Sept) | 63°F | 51°F | 1.5" | Fair |
Do not sealcoat. Rain returns in force (3.5 to 6.5 inches per month), and temperatures fall well below viable range. Any sealcoat applied in October or later will almost certainly fail.
The warmest major metro along the I-5 corridor south of Portland. The sealcoating window is slightly wider than other regions — late May through mid-September in good years. Eugene's position in the southern Willamette Valley gives it 2 to 3 extra degrees of warmth and slightly less rain than Salem.
Best window: July 1 through August 31. Visit our Eugene sealcoating page for local service details.
Central Valley location with moderate conditions. Follows the standard season calendar closely. Salem receives slightly more rain than Eugene but less than coastal areas.
Best window: July 1 through August 31.
Positioned closer to the Coast Range, Corvallis receives marginally more moisture from Pacific systems than Eugene or Salem. This can shorten the fall window by a week compared to Eugene.
Best window: July 1 through August 25.
Coastal locations have narrower windows due to persistent fog, lower temperatures, and higher humidity. Summer highs rarely exceed 68°F, and morning fog can delay application starts until 11:00 AM or later. Cure times run 50 to 100 percent longer than inland.
Best window: Late July through mid-September. Plan for 72 to 96-hour cure times rather than the 24 to 48 hours typical inland.
Here is the recommended scheduling timeline for Oregon property owners:
| When | What to Do |
|---|---|
| January – February | Research contractors. Review your pavement condition. |
| March | Request bids from 2 to 3 contractors. |
| April | Compare bids and confirm your contractor. |
| May | Finalize scheduling. Complete crack sealing and patching. |
| June – August | Application window. Stay flexible on exact dates. |
| September | Last-chance window for projects that were delayed. |
For a comprehensive seasonal planning approach, see our guide on the best time to sealcoat in Oregon.
Cojo Excavation and Asphalt schedules sealcoating projects across Oregon's I-5 corridor from Eugene to Salem. We book our summer calendar on a first-come basis starting each January. Contact us early for the best scheduling options.
Call 541-409-9848 or visit our sealcoating services page to request a bid.
A practical guide to sealcoating apartment and condo parking lots. Covers phased scheduling, tenant communication, cost allocation, liability, and ROI for property value.
Sealcoating timing for Oregon's Blue Mountains region including John Day, Prairie City, and the Pendleton area. High elevation, severe winters, and remote locations create unique scheduling needs.
Sealcoating timing guide for Oregon's western Cascade foothills including Sweet Home, Oakridge, and surrounding communities. Higher elevation and increased rainfall create a tighter schedule.
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