Last updated: May 3, 2025
Understanding the UV Index is crucial for residents of Washington, United States. As a region characterized by a Cfa climate, Washington experiences varying levels of ultraviolet radiation throughout the year, which can pose significant risks to skin health, including sunburn and long-term damage. Awareness of UV levels can empower you to take necessary precautions, especially during peak hours when the index reaches levels of 9 to 11, indicating a high risk of harm from unprotected sun exposure. Stay informed to protect your skin and enjoy the beautiful Washington outdoors safely!
Throughout the day, the UV Index peaks dramatically, starting at a mild 1 in the early morning at 7:00 AM and 8:00 AM. As the sun climbs higher, 9:00 AM sees a moderate increase to 3, but it’s not until 10:00 AM that the UV Index hits 5, signaling a need for some sun protection. The intensity truly soars at 11:00 AM, reaching 7, and by 12:00 PM it escalates to a striking 9, before soaring to its maximum of 11 at 1:00 PM. After the zenith, the index gradually recedes to 10 at 2:00 PM, and then descends slowly: 9 at 3:00 PM, 7 at 4:00 PM, and down to 4 by 5:00 PM. The evening brings relief, as the UV Index dips to 2 at 6:00 PM and finally settles back to 1 as the sun sets at 7:00 PM. Ensure to stay protected during those peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 5 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 9 | very high | 15 min |
| 16:00 | 7 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
As the seasons change, so too does the UV Index, highlighting the importance of sun protection for both visitors and residents. January and December see moderate levels (UV Index of 4), with a burn time of 30 minutes, while February ramps up to a high level (Index 7), decreasing burn time to 25 minutes. The high-risk months are clearly defined from March through August, where the UV Index reaches extreme levels (11) in May, June, and July, requiring caution with an effective burn time of just 10 minutes. April also registers a very high rating (10) with a 15-minute burn time, and August slightly decreases to a very high level again at 10. As autumn approaches, September (UV 9) and October (UV 8) remain critical, while November drops to a high UV Index of 6. In light of these variations, it is crucial for everyone to consider applying sunscreen, wearing protective clothing, and seeking shade during peak sun hours, particularly from March to August when the risk of skin damage is significantly heightened.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chicago UVI | 3 | 4 | 6 | 8 | 9 | 10 | 10 | 9 | 8 | 6 | 4 | 2 |
| Brooklyn UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| New York City UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| Los Angeles UVI | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| Washington | 4 | 7 | 9 | 10 | 11 | 11 | 11 | 10 | 9 | 8 | 6 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |