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Grass Valley, CA chak today UV index
California · Tuesday, September 29 chak EPA forecast
Today's forecast has not been published yet; this is the latest forecast, for Tuesday, September 29.
Sun protection needed from 11:00 to 17:00 (UV 3 or higher).
The EPA forecasts a peak UV index of 6 (High) in Grass Valley on Tuesday, September 29.
Hour by hour
| Time | UV index | Level |
|---|---|---|
| 09:00 | 1 | Low |
| 10:00 | 2 | Low |
| 11:00 | 4 | Moderate |
| 12:00 | 6 | High |
| 13:00 | 6 | High |
| 14:00 | 6 | High |
| 15:00 | 4 | Moderate |
| 16:00 | 3 | Moderate |
| 17:00 | 1 | Low |
What UV 6 (High) means today
Unprotected sun exposure chak high risk: skin ani eyes chak protection need kha. Middle of the day chak sun chak time reduce kha, shade seek kha, ani protective clothing, wide-brimmed hat, UV-blocking sunglasses ani broad-spectrum SPF 30+ sunscreen wear kha, every 2 hours reapplied.
Shadow rule: aokha shadow aokha chini kha chini, sun's UV khwchak - aokha rakha.
Grass Valley is at 2,410 feet (735 m). UV grows by roughly 10% with every 1,000 m of altitude, so it is stronger here than at sea level.
Typical UV index in Grass Valley by month
Average daily peak UV index over 2023–2024: highest in July (9.8), lowest in December (1.3). The average daily peak reaches 6 (high) or more in: April, May, June, July, August, September.
Monthly averages: hourly UV index under real sky conditions, clouds included, from NASA POWER satellite data (CERES), 2023–2024, on a 1° grid shared by nearby towns. The daily forecast above is the EPA's.
Aokha chini khong UV index
- Lincoln
42 km away6 - Linda
43 km away5 - Yuba City
49 km away6 - Rocklin
50 km away6 - Granite Bay
51 km away6 - Oroville
54 km away5 - Roseville
56 km away6 - El Dorado Hills
59 km away6
UV index scale
| UV index | Level |
|---|---|
| 0–2 | Low Average person chak sun's UV rays chak low danger. Bright days chak sunglasses wear kha. If you burn easily, cover up ani broad-spectrum SPF 30+ sunscreen use kha. Sand, water ani snow chak UV reflect kha ani exposure add kha. |
| 3–5 | Moderate Unprotected sun exposure chak moderate risk. Midday chak shade chak stay kha, when sun is strongest. Protective clothing, wide-brimmed hat ani UV-blocking sunglasses wear kha, ani broad-spectrum SPF 30+ sunscreen every 2 hours apply kha, even cloudy days chak, ani swimming or sweating chak after. |
| 6–7 | High Unprotected sun exposure chak high risk: skin ani eyes chak protection need kha. Middle of the day chak sun chak time reduce kha, shade seek kha, ani protective clothing, wide-brimmed hat, UV-blocking sunglasses ani broad-spectrum SPF 30+ sunscreen wear kha, every 2 hours reapplied. |
| 8–10 | Borobor Very high risk: unprotected skin ani eyes damaged kha ani quickly burn kha. Middle of the day chak sun chak time minimize kha, shade seek kha, ani clothing, wide-brimmed hat, UV-blocking sunglasses ani broad-spectrum SPF 30+ sunscreen chak cover up kha, every 2 hours reapplied. |
| 11+ | Extreme Extreme risk: unprotected skin ani eyes minutes chak burn kha. Middle of the day chak sun avoid kha try kha, shade chak stay kha, ani every protection use kha: clothing, wide-brimmed hat, UV-blocking sunglasses ani broad-spectrum SPF 30+ sunscreen, every 2 hours reapplied. |
Source: the EPA's hourly UV index forecast for ZIP code 95945, calculated by the National Weather Service from the ozone forecast, sun angle, elevation and expected clouds. Sunrise, solar noon and sunset are calculated for the city's coordinates.
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