Is it good to coat in Rapid City, SD this week?
A live 7-day go/no-go calendar for epoxy & resin floors in Rapid City, 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
- 4.3°F
- Overnight dew
- Watch
- Rain
- 41%
- Window
- 8am–5pm
Watch overnight dew — surface comes within 4.3°F of the dew point (margin is 5°F). Time the coat to dry well before evening.
- Dew margin
- 8.2°F
- Overnight dew
- Low
- Rain
- 2%
- Window
- 8am–5pm
Clear to coat: temps 67–82°F, RH under 31%, surface stays 8.2°F+ above the dew point, no rain in the cure window.
- Dew margin
- 6.8°F
- Overnight dew
- Low
- Rain
- 19%
- Window
- —
Too hot — high of 93°F is well over the 86°F ceiling; the film skins over before it can level or adhere.
- Dew margin
- 12.2°F
- Overnight dew
- Low
- Rain
- 27%
- Window
- 8am–5pm
Clear to coat: temps 66–86°F, RH under 60%, surface stays 12.2°F+ above the dew point, no rain in the cure window.
- Dew margin
- 4.6°F
- Overnight dew
- Watch
- Rain
- 32%
- Window
- —
Too hot — high of 93°F is well over the 86°F ceiling; the film skins over before it can level or adhere.
- Dew margin
- 11.2°F
- Overnight dew
- Low
- Rain
- 24%
- Window
- —
Too hot — high of 98°F is well over the 86°F ceiling; the film skins over before it can level or adhere.
- Dew margin
- 26.7°F
- Overnight dew
- Low
- Rain
- 29%
- Window
- 8am–5pm
Hot afternoon (87°F, ceiling 86°F) — coat early and follow the shade.
- Watch overnight dew — surface comes within 4.3°F of the dew point (margin is 5°F). Time the coat to dry well before evening.
- Hot afternoon (89°F, ceiling 86°F) — coat early and follow the shade.
- Some rain risk (41%) during the cure window — re-check the radar before you start.
Caution. These are forecast numbers — confirm the surface temperature on-site before you start.
Why these thresholds
Installing within 5°F of the dew point causes amine blush / carbamation — a cloudy, greasy, hazed floor. The slab surface temp, not the air, is what counts.
- • Surface temp must stay 5°F above the dew point through application and cure (ASTM D3276 / ISO 8502-42).
- • Air + surface in the 50–86°F band (low-temp lines to 50°F).
- • Humidity under 85%; ideally under 80%.
- • 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.