Exterior Painting Weather in Idaho: Best Months by City
Exterior Painting season in Idaho, city by city: peak months, season boundaries, and annual workable-day counts from NOAA 1991–2020 normals. Coeur d'Alene leads with 127 workable days a year; Nampa runs the shortest at 91.
Idaho is not one climate: Coeur d'Alene banks 127 workable exterior painting days a year while Nampa gets 91 — a spread the table below itemizes month by month. Season boundaries mark the first and last month averaging 8+ workable days against the label rules (50–90°F, nights 35°F+).
Statewide, September is the strongest month — it tops or ties the table in most listed cities. The live strips on each city page decide the week; this table decides the month. Scoring rules: methodology; the national playbook: the exterior painting guide.
Cities in Idaho
| City | Peak months | Season | Workable days/yr |
|---|---|---|---|
| Boise | Sep, Jun, May | April–June | 114 |
| Nampa | Sep, Jun, May | May–June | 91 |
| Coeur d'Alene | Aug, Jul, Sep | May–September | 127 |
| Meridian | Sep, Jun, May | April–June | 114 |
| Idaho Falls | Jul, Aug, Sep | May–September | 118 |
The rules behind these numbers
| Check | Threshold | Why it matters |
|---|---|---|
| Air temperature | 50–90°F (low-temp formulas from 35°F) | Standard latex wants 50°F+. Some low-temperature formulas are rated down to 35°F. |
| Overnight low | ≥35°F during the first 24 h (≥40°F preferred) | Paint keeps curing overnight; a low under 40°F stalls standard latex. |
| Dry before | ≤0.05" rain in the prior 12 h; watch back to 24 h | The surface must be dry to the touch and out of a recent soak. |
| Dry after | <0.05" rain for 24 h after | Rain inside the first 24 hours can streak or wash fresh paint. |
| Evening dew-point spread | ≥5°F from 6–11 pm | Surface should stay at least 5°F above the dew point; dew flat-spots fresh paint. |
| Daytime humidity | ≤80% | High humidity extends recoat and cure times. |
| Wind | ≤15 mph (brush only up to 20 mph) | Wind dries the leading edge too fast and carries overspray. |
Always follow your product label — formulas vary. The table above is the typical range across major manufacturers, not a promise about your can.
Related
Other tasks in Idaho
- Deck Staining in Idaho
- Driveway Sealing in Idaho
- Concrete Pouring in Idaho
- Roof Coating in Idaho
- Lawn Seeding in Idaho