Last updated: July 2, 2025
Understanding the UV Index is crucial for residents of Johnstown Bridge, Ireland, as it plays a vital role in protecting skin health and preventing sunburn. With its temperate maritime climate (Cfb) leading to varying UV exposures, awareness of UV levels helps residents make informed decisions about sun protection throughout the day. The UV Index in Johnstown Bridge peaks between 12:00 PM and 2:00 PM, reaching levels of 8, indicating a high risk of harm from unprotected sun exposure. Recognizing these trends can ensure that you enjoy the outdoors while safeguarding your skin from potential damage.
The UV Index throughout the day reveals a distinct pattern of increasing intensity as the sun rises. At 07:00, the index starts at a mild 1, gradually climbing to 2 by 08:00. As the day progresses, the intensity ramps up, peaking at an impressive 8 during the hours of 13:00 and 14:00—a clear indication that midday sun is at its most potent. After this height, the index begins to descend, dropping back to 6 at 16:00, and later settling at a more manageable 1 by 19:00. This hourly data clearly underscores the importance of sun protection during the midday hour for outdoor activities.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 4 | moderate | 30 min |
| 11:00 | 6 | high | 25 min |
| 12:00 | 7 | high | 25 min |
| 13:00 | 8 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 7 | high | 25 min |
| 16:00 | 6 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV radiation levels fluctuate significantly, necessitating varying levels of sun protection. From January to February, the UV Index remains low (1-2), allowing for extended exposure times without burning, approximately 45 minutes. However, as spring approaches, the UV Index rises, reaching moderate levels (4-5) in March and April, where 30-minute burn times apply. The summer months of May through July present the highest risk, with UV Index values peaking at 8 and very high exposure categories, meaning that unprotected skin can burn in just 15 minutes. August sees a slight decrease, but still maintains a high UV Index of 7, with a burn time of 25 minutes. In contrast, September to October return to moderate levels, allowing for 30-minute safe exposure, while November and December drop back down to low levels (1-2) with burn times of 45 minutes. Visitors and residents are strongly advised to take precautions during the high-risk months of May through July, utilizing sunscreen, protective clothing, and seeking shade to minimize UV exposure and safeguard skin health.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Johnstown Bridge | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 3 | 2 | 1 |
| Gaillimh UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 3 | 2 | 1 |
| Tallaght UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 3 | 2 | 1 |
| Dublin UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 3 | 2 | 1 |
| Luimneach UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 4 | 2 | 1 |
| Cork UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 4 | 2 | 1 |