Is it good to paint in Juneau, AK this week?
A live 7-day go/no-go calendar for exterior paint in Juneau, 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
- -0.4°F
- Overnight dew
- High
- Rain
- 92%
- Window
- —
High condensation risk overnight — surface dips to within -0.4°F of the 49°F dew point (low 49°F, 59% cloud, 4 mph wind). A fresh paint can blush/blister. Stop 4h before dew falls.
- Dew margin
- 3.2°F
- Overnight dew
- Watch
- Rain
- 41%
- Window
- 8am–5pm
Watch overnight dew — surface comes within 3.2°F of the dew point (margin is 5°F). Time the coat to dry well before evening.
- Dew margin
- 1.6°F
- Overnight dew
- High
- Rain
- 65%
- Window
- —
High condensation risk overnight — surface dips to within 1.6°F of the 47°F dew point (low 48°F, 100% cloud, 4 mph wind). A fresh paint can blush/blister. Stop 4h before dew falls.
- Dew margin
- 0.6°F
- Overnight dew
- High
- Rain
- 77%
- Window
- —
High condensation risk overnight — surface dips to within 0.6°F of the 47°F dew point (low 48°F, 97% cloud, 1 mph wind). A fresh paint can blush/blister. Stop 4h before dew falls.
- Dew margin
- -1.1°F
- Overnight dew
- High
- Rain
- 72%
- Window
- —
High condensation risk overnight — surface dips to within -1.1°F of the 46°F dew point (low 44°F, 95% cloud, 2 mph wind). A fresh paint can blush/blister. Stop 4h before dew falls.
- Dew margin
- -0.2°F
- Overnight dew
- High
- Rain
- 90%
- Window
- —
High condensation risk overnight — surface dips to within -0.2°F of the 50°F dew point (low 49°F, 100% cloud, 5 mph wind). A fresh paint can blush/blister. Stop 4h before dew falls.
- Dew margin
- -0.7°F
- Overnight dew
- High
- Rain
- 79%
- Window
- —
High condensation risk overnight — surface dips to within -0.7°F of the 48°F dew point (low 47°F, 97% cloud, 1 mph wind). A fresh paint can blush/blister. Stop 4h before dew falls.
- High condensation risk overnight — surface dips to within -0.4°F of the 49°F dew point (low 49°F, 59% cloud, 4 mph wind). A fresh paint can blush/blister. Stop 4h before dew falls.
- Humidity peaks at 97% — well above the 85% ceiling; cure stalls and moisture gets trapped.
- Rain likely in the 24h cure window (92% chance, ~3.1mm) — it can wash out or mar an uncured paint.
Hold off. These are forecast numbers — confirm the surface temperature on-site before you start.
Why these thresholds
Overnight dew condensing on a fresh coat causes blistering, surfactant leaching and peeling — the cause of 40%+ of exterior paint failures.
- • Surface temp must stay 5°F above the dew point through application and cure (ASTM D3276 / ISO 8502-42).
- • Air + surface in the 50–85°F band (low-temp lines to 35°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.