Last updated: July 2, 2025
In Si Prachan, Thailand, understanding the UV Index is crucial for protecting your skin health and preventing sunburn. With the region's tropical climate, which enjoys abundant sunshine year-round, UV levels can soar, particularly during midday hours. Knowing the daily UV Index allows residents and visitors alike to take proactive measures against harmful ultraviolet radiation, ensuring a safe and enjoyable outdoor experience. During peak hours, as the UV Index can reach levels above 12, it’s essential to be vigilant and use appropriate sun protection strategies to safeguard against skin damage and long-term health risks. Stay informed and shield yourself under the Thai sun!
As the sun rises, the UV Index starts its slow climb, peaking at 13 between noon and 1 PM, signaling extreme UV exposure. The day begins gently at 7 AM with a minimal index of 1, but by 10 AM, it reaches 9, urging sun-sensitive individuals to seek protection. The highest reading of 13 persists for two hours, making midday the most critical time for sun safety. As the afternoon rolls in, the index gradually decreases, dipping to 7 by 3 PM, and further waning into the evening with values of 4 at 4 PM, 2 at 5 PM, and falling to a comfortable 1 by 6 PM. Finally, the UV Index settles at 0 after sunset, marking the end of a sun-drenched day.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 5 | moderate | 30 min |
| 10:00 | 9 | very high | 15 min |
| 11:00 | 12 | extreme | 10 min |
| 12:00 | 13 | extreme | 10 min |
| 13:00 | 13 | extreme | 10 min |
| 14:00 | 11 | extreme | 10 min |
| 15:00 | 7 | high | 25 min |
| 16:00 | 4 | moderate | 30 min |
| 17:00 | 2 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
The UV Index experiences significant seasonal changes, peaking during the warmer months. January begins with a UV Index of 9, categorized as very high, with a burn time of just 15 minutes. As we move into February and March, the Index escalates to 12 and 13, tipping into the extreme category, where careful sun protection is essential. From April to August, the UV Index consistently remains at 13 to 14, emphasizing the need for aggressive sun safety measures with a burn time of only 10 minutes. The Index begins to decline in September and October but stays in the extreme range of 12 to 13. High-risk months for UV exposure are predominantly between February and August, urging both residents and visitors to prioritize sun protection—such as wearing sunscreen, hats, and protective clothing—during these critical times. The lower UV levels in November and December still warrant attention, as they feature a 10 and 9 UV Index, respectively, reminding us that skin protection is important year-round.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Si Prachan | 9 | 12 | 13 | 14 | 13 | 13 | 13 | 14 | 13 | 12 | 10 | 9 |
| Mueang Nonthaburi UVI | 10 | 12 | 14 | 13 | 14 | 13 | 14 | 14 | 13 | 12 | 9 | 8 |
| Samut Prakan UVI | 10 | 12 | 14 | 13 | 14 | 13 | 14 | 14 | 13 | 12 | 9 | 8 |
| Bangkok UVI | 10 | 12 | 14 | 13 | 14 | 13 | 14 | 14 | 13 | 12 | 9 | 8 |
| Udon Thani UVI | 9 | 11 | 13 | 14 | 14 | 13 | 14 | 14 | 14 | 12 | 10 | 9 |
| Chon Buri UVI | 10 | 13 | 14 | 14 | 14 | 13 | 14 | 14 | 13 | 13 | 10 | 9 |