Is it good to stain in Manchester, NH this week?
A live 7-day go/no-go calendar for deck & fence stain in Manchester, 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
- 1.5°F
- Overnight dew
- High
- Rain
- 21%
- Window
- —
High condensation risk overnight — surface dips to within 1.5°F of the 63°F dew point (low 63°F, 12% cloud, 2 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 4.2°F
- Overnight dew
- High
- Rain
- 16%
- Window
- —
High condensation risk overnight — surface dips to within 4.2°F of the 53°F dew point (low 57°F, 0% cloud, 6 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 3.4°F
- Overnight dew
- High
- Rain
- 22%
- Window
- —
High condensation risk overnight — surface dips to within 3.4°F of the 51°F dew point (low 54°F, 0% cloud, 4 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 4.4°F
- Overnight dew
- High
- Rain
- 2%
- Window
- —
High condensation risk overnight — surface dips to within 4.4°F of the 51°F dew point (low 55°F, 16% cloud, 2 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- -3.1°F
- Overnight dew
- High
- Rain
- 47%
- Window
- —
High condensation risk overnight — surface dips to within -3.1°F of the 67°F dew point (low 64°F, 75% cloud, 4 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 3.2°F
- Overnight dew
- High
- Rain
- 40%
- Window
- —
High condensation risk overnight — surface dips to within 3.2°F of the 52°F dew point (low 55°F, 0% cloud, 4 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 4.9°F
- Overnight dew
- Watch
- Rain
- 4%
- Window
- 8am–7pm
Watch overnight dew — surface comes within 4.9°F of the dew point (margin is 5°F). Time the coat to dry well before evening.
- High condensation risk overnight — surface dips to within 1.5°F of the 63°F dew point (low 63°F, 12% cloud, 2 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
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.
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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.