First Summerday in 2026 on 2026-05-24
May 25, 2026Yesterday’s maximum temperature of 31.0 degrees Celsius marked the first summer day of the year, with 13.7 hours of sunshine. This occurrence ranks as the 139th earliest first summer day since 1876, placing it in the 99th percentile.
Yesterday’s maximum temperature reached 31.0 degrees Celsius, and I am delighted to announce that this marks the first summer day of the year. The day brought 13.7 hours of sunshine, which is 95 percent of the possible sunshine.
Comparing this date to historic records, the occurrence ranks as the 139th earliest first summer day since 1876, placing it in the 99th percentile. Table 1 shows the top earliest first summer days, with the earliest on record occurring on March 30, 1989. Table 2 shows the latest first summer days, with the latest on record occurring on June 15, 1991.
Table 1: Top 5 Years with earliest Summer Day
| Year | Date | Day of Year | Max. Temperature [°C] | Avg. Temperature [°C] |
|---|---|---|---|---|
| 1989 | 1989-03-30 | 89 | 25.2 | 16.4 |
| 2021 | 2021-03-31 | 90 | 25.0 | 15.7 |
| 1949 | 1949-04-04 | 94 | 25.0 | 15.4 |
| 1985 | 1985-04-04 | 94 | 25.2 | 15.8 |
| 1961 | 1961-04-05 | 95 | 25.1 | 14.9 |
Table 2: Bottom 5 Years with latest Summer Day
| Year | Date | Day of Year | Max. Temperature [°C] | Avg. Temperature [°C] |
|---|---|---|---|---|
| 1991 | 1991-06-15 | 166 | 26.8 | 19.9 |
| 1984 | 1984-06-13 | 165 | 25.5 | 18.3 |
| 1970 | 1970-06-07 | 158 | 26.1 | 19.8 |
| 1911 | 1911-06-06 | 157 | 25.5 | 19.4 |
| 1980 | 1980-06-05 | 157 | 25.1 | 17.7 |
Figure 1: First Summer-Day since 1876
🤖 This text was generated with the assistance of AI. All quantitative statements are derived directly from the dataset listed under Data Source.