Is it good to stain in Boston, MA this week?
A live 7-day go/no-go calendar for deck & fence stain in Boston, built from the local forecast against the 5°F-above-dew-point rule. We lead with the signal a weather app misses: overnight condensation risk.
- Dew margin
- 2.1°F
- Overnight dew
- High
- Rain
- 2%
- Window
- —
High condensation risk overnight — surface dips to within 2.1°F of the 61°F dew point (low 62°F, 4% cloud, 5 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 1.4°F
- Overnight dew
- High
- Rain
- 1%
- Window
- —
High condensation risk overnight — surface dips to within 1.4°F of the 59°F dew point (low 60°F, 18% cloud, 3 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 0.6°F
- Overnight dew
- High
- Rain
- 54%
- Window
- —
High condensation risk overnight — surface dips to within 0.6°F of the 66°F dew point (low 66°F, 100% cloud, 4 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 0.3°F
- Overnight dew
- High
- Rain
- 41%
- Window
- —
High condensation risk overnight — surface dips to within 0.3°F of the 66°F dew point (low 67°F, 30% cloud, 2 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 2.7°F
- Overnight dew
- High
- Rain
- 7%
- Window
- —
High condensation risk overnight — surface dips to within 2.7°F of the 66°F dew point (low 69°F, 5% cloud, 6 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 2.8°F
- Overnight dew
- Watch
- Rain
- 42%
- Window
- 8am–5pm
Watch overnight dew — surface comes within 2.8°F of the dew point (margin is 5°F). Time the coat to dry well before evening.
- Dew margin
- 0.9°F
- Overnight dew
- High
- Rain
- 43%
- Window
- —
High condensation risk overnight — surface dips to within 0.9°F of the 71°F dew point (low 72°F, 85% cloud, 10 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- High condensation risk overnight — surface dips to within 2.1°F of the 61°F dew point (low 62°F, 4% cloud, 5 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Humidity peaks at 96% — well above the 85% ceiling; cure stalls and moisture gets trapped.
Hold off. These are forecast numbers — confirm the surface temperature on-site before you start.
Why these thresholds
Stain applied to a damp or dew-wet board can't penetrate — it beads, stays tacky and flakes. Wood must be dry and stay above the dew point while it sets.
- • Surface temp must stay 5°F above the dew point through application and cure (ASTM D3276 / ISO 8502-42).
- • Air + surface in the 50–90°F band (low-temp lines to 45°F).
- • Humidity under 85%; ideally under 70%.
- • No rain for 24h after application.
- • We use the forecast ground-surface temperature as a surface-temp proxy — confirm on-site with an IR thermometer.
Free in the beta
Watch this job site 24/7
Get an email the moment overnight dew, rain, or an out-of-range stretch threatens a fresh coat — and a morning digest with the best window ahead. No app to check; we watch the forecast for you.