Is it good to stain in San Antonio, TX this week?
A live 7-day go/no-go calendar for deck & fence stain in San Antonio, 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
- 4.2°F
- Overnight dew
- Watch
- Rain
- 2%
- Window
- 9am–5pm
Watch overnight dew — surface comes within 4.2°F of the dew point (margin is 5°F). Time the coat to dry well before evening.
- Dew margin
- 1.5°F
- Overnight dew
- High
- Rain
- 0%
- Window
- —
High condensation risk overnight — surface dips to within 1.5°F of the 73°F dew point (low 74°F, 31% cloud, 2 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 1.5°F
- Overnight dew
- High
- Rain
- 1%
- Window
- —
High condensation risk overnight — surface dips to within 1.5°F of the 72°F dew point (low 73°F, 15% cloud, 7 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 1.9°F
- Overnight dew
- High
- Rain
- 1%
- Window
- —
High condensation risk overnight — surface dips to within 1.9°F of the 71°F dew point (low 72°F, 8% cloud, 4 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 0.9°F
- Overnight dew
- High
- Rain
- 4%
- Window
- —
High condensation risk overnight — surface dips to within 0.9°F of the 74°F dew point (low 75°F, 93% cloud, 5 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 1.2°F
- Overnight dew
- High
- Rain
- 1%
- Window
- —
High condensation risk overnight — surface dips to within 1.2°F of the 74°F dew point (low 75°F, 38% cloud, 5 mph wind). A fresh stain can blush/blister. Stop 4h before dew falls.
- Dew margin
- 8.2°F
- Overnight dew
- Low
- Rain
- 0%
- Window
- —
Too hot — high of 100°F is well over the 90°F ceiling; the film skins over before it can level or adhere.
- Watch overnight dew — surface comes within 4.2°F of the dew point (margin is 5°F). Time the coat to dry well before evening.
- Hot afternoon (95°F, ceiling 90°F) — stain early and follow the shade.
- High humidity (86%, over the 85% mark) slows drying — keep an eye on the cure window.
Caution. 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.