Marshalltown weather in May: Marshalltown, Iowa: normal highs, lows, rain and records for May
Marshalltown in May has a normal high of 71°F and a normal low of 49°F, a daily mean of 60°F, rising from 66°F on the 1st to 77°F by the 31st. Measurable precipitation falls on 13 days in a normal May, 4.88 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 22°C and low of 9°C, 124 mm of precipitation in May.
- NOAA stationMarshalltown Municipal Airport
- Station IDUSW00094988
- Location42.11°N 92.92°W
- Elevation974 ft (297 m)
- From the center5 miles
- Population27,886
- Jan 28° 10°
- Feb 32° 14°
- Mar 46° 26°
- Apr 60° 37°
- May 71° 49°
- Jun 81° 59°
- Jul 83° 62°
- Aug 81° 60°
- Sep 75° 51°
- Oct 62° 39°
- Nov 46° 26°
- Dec 33° 16°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Marshalltown in May?
The normal high is 71°F and the normal low 49°F, for a daily mean of 60.0°F. May is 11.7°F warmer than April and 9.7°F cooler than June. May is the 5th warmest month of the year in Marshalltown and the 2nd wettest. Across the month the normal high rises 11°F, from 66°F on May 1 to 77°F on May 31. From one year to the next May's mean temperature typically moves about 3.0°F either way (NOAA's standard deviation), so roughly two Mays in three average between 57°F and 63°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 44%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| May 1 | 66°F | 42°F | 40% | 26% |
| May 8 | 68°F | 45°F | 42% | 26% |
| May 15 | 71°F | 48°F | 42% | 26% |
| May 22 | 74°F | 51°F | 43% | 27% |
| May 31 | 77°F | 55°F | 44% | 27% |
Every day of May: normal high, low and chance of precipitation (warmest afternoon May 31, coldest night May 1)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| May 1 | 66°F | 42°F | 40% | 26% | 14 h |
| May 2 | 66°F | 43°F | 41% | 26% | 14 h |
| May 3 | 66°F | 43°F | 41% | 26% | 14 h 10 min |
| May 4 | 67°F | 44°F | 41% | 26% | 14 h 10 min |
| May 5 | 67°F | 44°F | 41% | 26% | 14 h 10 min |
| May 6 | 67°F | 44°F | 41% | 26% | 14 h 10 min |
| May 7 | 68°F | 45°F | 42% | 26% | 14 h 10 min |
| May 8 | 68°F | 45°F | 42% | 26% | 14 h 20 min |
| May 9 | 69°F | 46°F | 42% | 26% | 14 h 20 min |
| May 10 | 69°F | 46°F | 42% | 26% | 14 h 20 min |
| May 11 | 69°F | 47°F | 42% | 26% | 14 h 20 min |
| May 12 | 70°F | 47°F | 42% | 26% | 14 h 30 min |
| May 13 | 70°F | 48°F | 42% | 26% | 14 h 30 min |
| May 14 | 70°F | 48°F | 42% | 26% | 14 h 30 min |
| May 15 | 71°F | 48°F | 42% | 26% | 14 h 30 min |
| May 16 | 71°F | 49°F | 42% | 26% | 14 h 30 min |
| May 17 | 72°F | 49°F | 43% | 26% | 14 h 40 min |
| May 18 | 72°F | 50°F | 43% | 26% | 14 h 40 min |
| May 19 | 72°F | 50°F | 43% | 26% | 14 h 40 min |
| May 20 | 73°F | 51°F | 43% | 26% | 14 h 40 min |
| May 21 | 73°F | 51°F | 43% | 26% | 14 h 40 min |
| May 22 | 74°F | 51°F | 43% | 27% | 14 h 50 min |
| May 23 | 74°F | 52°F | 43% | 27% | 14 h 50 min |
| May 24 | 74°F | 52°F | 43% | 27% | 14 h 50 min |
| May 25 | 75°F | 53°F | 44% | 27% | 14 h 50 min |
| May 26 | 75°F | 53°F | 44% | 27% | 14 h 50 min |
| May 27 | 75°F | 53°F | 44% | 27% | 14 h 50 min |
| May 28 | 76°F | 54°F | 44% | 27% | 15 h |
| May 29 | 76°F | 54°F | 44% | 27% | 15 h |
| May 30 | 76°F | 55°F | 44% | 27% | 15 h |
| May 31 | 77°F | 55°F | 44% | 27% | 15 h |
- Normal high
- 71°FMay average
- Normal low
- 49°FMay average
- Precipitation
- 4.88 inmonth total
- Days with precipitation
- 130.01 inch or more
- Days at 90°F or more
- 1
- Nights at 32°F or colder
- 1
- Daylight
- 14 h to 15 hMay 1 to May 31
- Days at 70°F or more
- 18
- Days at 80°F or more
- 7
- Sunshine
- 71%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00094988; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Marshalltown in May?
On a given May day the chance of 0.01 inch or more is 42% on average, highest around May 25 (44%). In all, 4.88 in falls on 13 days of a normal May, 1 of them with an inch or more.
In a normal May in Marshalltown, 1 days reach 90°F and 1 nights fall to freezing.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00094988.
What are the records for May in Marshalltown?
The warmest May temperature on this station's record (since 1996) is 100°F, on May 27, 2018; the coldest is 22°F, on May 3, 2005. The wettest May brought 15.75 in (2013).
The May mean against the 1991-2020 normal of 60.0°F: 2021 58.5°F (−1.5), 2022 61.1°F (+1.1), 2023 63.5°F (+3.5), 2024 62.4°F (+2.4), 2025 59.5°F (−0.5), 2026 60.8°F (+0.8). 4 of 6 ran warmer than normal.
| May | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 58.5°F | −1.5°F | 3.30 in |
| 2022 | 61.1°F | +1.1°F | 2.93 in |
| 2023 | 63.5°F | +3.5°F | 2.59 in |
| 2024 | 62.4°F | +2.4°F | 7.82 in |
| 2025 | 59.5°F | −0.5°F | 2.65 in |
| 2026 | 60.8°F | +0.8°F | 3.40 in |
Source: records: ACIS, station USW00094988; recent months: ACIS, station USW00094988. Records and recent months use complete months only.
How does May in Marshalltown compare across Iowa?
Across the 132 places PlainClimate covers in Iowa, May normal highs run from 66°F in Northwood to 74°F in Glenwood; Marshalltown's is 71°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.