Casco Weather in May
Average highs run from 54°F on May 1 to 65°F on May 31, and lows from 39°F to 49°F. Normal precipitation for the month is 3.30 in over about 10 wet days.
May day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
May at a glance
- Average high
- 60°F
- Average low
- 44°F
- Precipitation
- 3.30 in
- Record high
- 91°FMay 28, 1944
- Record low
- 20°FMay 4, 1907
- Chance of a freeze
- 52%
- Daylight
- 14 h 14 min to 15 h 19 min
- Cloud cover
- 72%
- Humidity
- 78%
- Dew point
- 44°F
- Wind
- 13.0 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| May 1 | 54°F | 39°F | 85°F 1952 | 21°F 1907 | 31% | 1% |
| May 2 | 55°F | 39°F | 81°F 1951 | 21°F 1909 | 31% | 1% |
| May 3 | 55°F | 40°F | 82°F 1928 | 22°F 1911 | 31% | 1% |
| May 4 | 55°F | 40°F | 82°F 1934 | 20°F 1907 | 31% | 1% |
| May 5 | 56°F | 40°F | 89°F 1930 | 24°F 1910 | 31% | 1% |
| May 6 | 56°F | 41°F | 89°F 1934 | 25°F 1968 | 32% | 1% |
| May 7 | 57°F | 41°F | 82°F 1936 | 25°F 1925 | 32% | 1% |
| May 8 | 57°F | 41°F | 83°F 1936 | 20°F 1925 | 32% | 1% |
| May 9 | 57°F | 42°F | 83°F 2000 | 25°F 1947 | 32% | 0% |
| May 10 | 58°F | 42°F | 82°F 1987 | 21°F 1966 | 32% | 0% |
| May 11 | 58°F | 42°F | 81°F 1922 | 23°F 1907 | 32% | 0% |
| May 12 | 58°F | 43°F | 84°F 1977 | 24°F 1934 | 32% | 0% |
| May 13 | 59°F | 43°F | 89°F 1977 | 23°F 1923 | 32% | 0% |
| May 14 | 59°F | 43°F | 87°F 1977 | 23°F 1910 | 32% | 0% |
| May 15 | 60°F | 44°F | 85°F 1932 | 25°F 1914 | 32% | 0% |
| May 16 | 60°F | 44°F | 86°F 1962 | 28°F 1950 | 32% | 0% |
| May 17 | 60°F | 44°F | 86°F 1911 | 30°F 1983 | 32% | 0% |
| May 18 | 61°F | 45°F | 84°F 1998 | 30°F 1915 | 31% | 0% |
| May 19 | 61°F | 45°F | 86°F 1996 | 28°F 2002 | 31% | 0% |
| May 20 | 61°F | 45°F | 89°F 1972 | 26°F 2002 | 31% | 0% |
| May 21 | 62°F | 46°F | 88°F 1921 | 25°F 1907 | 31% | 0% |
| May 22 | 62°F | 46°F | 89°F 1921 | 27°F 1967 | 31% | 0% |
| May 23 | 62°F | 47°F | 85°F 1921 | 26°F 1963 | 31% | 0% |
| May 24 | 63°F | 47°F | 84°F 1991 | 31°F 1934 | 31% | 0% |
| May 25 | 63°F | 47°F | 83°F 2010 | 27°F 1934 | 31% | 0% |
| May 26 | 63°F | 48°F | 90°F 2018 | 30°F 1949 | 31% | 0% |
| May 27 | 64°F | 48°F | 86°F 2026 | 30°F 1910 | 31% | 0% |
| May 28 | 64°F | 48°F | 91°F 1944 | 30°F 1930 | 31% | 0% |
| May 29 | 65°F | 49°F | 91°F 1944 | 31°F 1947 | 31% | 0% |
| May 30 | 65°F | 49°F | 88°F 1939 | 31°F 1973 | 31% | 0% |
| May 31 | 65°F | 49°F | 91°F 1925 | 33°F 1916 | 31% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (CDT).
- May 1
- sunrise 5:41 AM, sunset 7:55 PM
- May 31
- sunrise 5:09 AM, sunset 8:28 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00474195 (Kewaunee), public domain. Records: NOAA GHCN-Daily, station USC00478267, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.