Last updated: May 6, 2024
Under the Köppen–Geiger climate classification Onset features a humid subtropical climate (Cfa).Temperatures typically range between 1 °C (34 °F) and 23 °C (74 °F) through the year, but rarely can drop to -19 °C (-1 °F) or can rise to as high as 37 °C (98 °F).The average annual precipitation amounts to about 1233 mm (48.5 inches) and receives 126 rainy days on the 1 mm (0.04 inches) threshold annually.Onset enjoys an average of 3034 hours of sunshine throughout the year, and daylight varies from 9 hours 10 minutes to 15 hours 9 minutes per day.
The warmest months in Onset are June, July and August, with daily mean temperatures ranging from 19 to 23 °C (67 - 74 °F) throughout the day. The coldest temperatures usually occur in January, February and December, when daily mean temperatures range from 1 to 3 °C (34 - 38 °F) throughout the day. On average each year, Onset experiences 48 days above 25 °C (77.0 °F) and 70 days below 0 °C (32.0 °F).
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Maximum | 19°C (66°F) | 17°C (64°F) | 18°C (65°F) | 24°C (76°F) | 30°C (87°F) | 32°C (90°F) | 37°C (98°F) | 34°C (94°F) | 30°C (87°F) | 26°C (79°F) | 21°C (71°F) | 17°C (63°F) |
Mean maximum | 14°C (57°F) | 14°C (58°F) | 15°C (60°F) | 19°C (67°F) | 27°C (81°F) | 29°C (84°F) | 33°C (91°F) | 31°C (89°F) | 28°C (82°F) | 24°C (76°F) | 20°C (68°F) | 16°C (60°F) |
Average high | 4°C (40°F) | 5°C (42°F) | 7°C (46°F) | 12°C (54°F) | 17°C (64°F) | 23°C (74°F) | 26°C (80°F) | 26°C (80°F) | 23°C (73°F) | 18°C (64°F) | 11°C (53°F) | 6°C (43°F) |
Daily mean | 1°C (34°F) | 2°C (36°F) | 4°C (39°F) | 9°C (48°F) | 14°C (57°F) | 19°C (67°F) | 23°C (74°F) | 23°C (74°F) | 19°C (67°F) | 14°C (58°F) | 8°C (46°F) | 3°C (38°F) |
Average low | -2°C (28°F) | -2°C (29°F) | 1°C (33°F) | 6°C (43°F) | 11°C (52°F) | 16°C (61°F) | 20°C (68°F) | 20°C (68°F) | 16°C (61°F) | 11°C (52°F) | 4°C (39°F) | -0°C (32°F) |
Mean minimum | -14°C (8°F) | -12°C (10°F) | -8°C (18°F) | 0°C (33°F) | 5°C (42°F) | 11°C (52°F) | 16°C (60°F) | 15°C (59°F) | 11°C (51°F) | 4°C (39°F) | -5°C (23°F) | -8°C (18°F) |
Minimum | -19°C (-1°F) | -15°C (5°F) | -12°C (11°F) | -2°C (29°F) | 3°C (38°F) | 9°C (48°F) | 14°C (57°F) | 13°C (55°F) | 9°C (48°F) | 0°C (33°F) | -9°C (17°F) | -14°C (6°F) |
Compare temperature, precipitation, sunshine, UV index in Onset, Massachusetts, United States with other places around the world.
Onset usually has the most precipitation in April, October and December, with an average of 11 rainy days and 127 mm (5.0 inches) of precipitation per month.The driest months in Onset are January, June and August. On average, 84 mm (3.3 inches) of precipitation falls during these months.
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Average precipitation mm (inches) | 82 (3.2) | 97 (3.8) | 107 (4.2) | 122 (4.8) | 98 (3.9) | 90 (3.5) | 102 (4.0) | 81 (3.2) | 102 (4.0) | 143 (5.6) | 93 (3.7) | 116 (4.6) |
Average precipitation days (≥ 1 mm) | 8 | 11 | 10 | 13 | 12 | 10 | 10 | 11 | 10 | 11 | 10 | 10 |
The sunniest months in Onset are June, July and August, when the sun shines an average of 10 hours 54 minutes a day.Least sunny months in Onset: January, February and December receive an average of 5 hours 34 minutes of sunshine daily.
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Mean monthly sunshine hours | 148 | 186 | 259 | 246 | 297 | 327 | 347 | 329 | 280 | 234 | 205 | 172 |
Mean daily daylight hours | 9h 31m | 10h 36m | 11h 58m | 13h 22m | 14h 33m | 15h 9m | 14h 49m | 13h 46m | 12h 25m | 11h 1m | 9h 48m | 9h 10m |
Onset experiences the highest level of ultraviolet (UV) radiation in May, June and August, when the maximum UV index can reach values of 9 - 10, which corresponds to the Very High category of sun exposure.January, November and December are in the Low / Moderate exposure category. In these months, the maximum values of the UV index do not exceed 4. For more detailed information, check out our hourly Onset UV Index data.
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
UV Index (month maximum) | 3 | 5 | 6 | 8 | 9 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |