As of 10:16 AM EDT on August 16, 2026, all 8 cities in Gratiot County, MI in our database have a UV Index reading of Low. The city with the highest UV Index reading right now is St. Louis, MI with a reading of 1.4.
Over the next 24 hours, the highest UV Index reading in Gratiot County, MI is expected to be 6.8 in Alma between 1:00 PM - 2:00 PM EDT today.
| Range | 0 - 2 | 3 - 5 | 6 - 7 | 8 - 10 | 11+ |
|---|---|---|---|---|---|
| Color | |||||
| Risk | Low | Moderate | High | Very High | Extreme |