Longmont weather in May: Longmont, Colorado: normal highs, lows, rain and records for May
Longmont in May has a normal high of 73°F and a normal low of 41°F, a daily mean of 57°F, rising from 67°F on the 1st to 78°F by the 31st. Measurable precipitation falls on 10 days in a normal May, 1.97 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 23°C and low of 5°C, 50 mm of precipitation in May.
- NOAA stationLongmont (2 mi ESE)
- Station IDUSC00055116
- Location40.17°N 105.08°W
- Elevation4,950 ft (1,509 m)
- From the center1 miles
- Population99,818
- Jan 45° 14°
- Feb 47° 17°
- Mar 57° 26°
- Apr 63° 32°
- May 73° 41°
- Jun 84° 51°
- Jul 91° 55°
- Aug 88° 54°
- Sep 80° 46°
- Oct 66° 33°
- Nov 54° 24°
- Dec 45° 15°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Longmont in May?
The normal high is 73°F and the normal low 41°F, for a daily mean of 57.1°F. May is 9.3°F warmer than April and 10.1°F cooler than June. May is the 5th warmest month of the year in Longmont and the 2nd wettest. Across the month the normal high rises 11°F, from 67°F on May 1 to 78°F on May 31. From one year to the next May's mean temperature typically moves about 2.9°F either way (NOAA's standard deviation), so roughly two Mays in three average between 54°F and 60°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 33%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| May 1 | 67°F | 36°F | 28% | 18% |
| May 8 | 70°F | 39°F | 29% | 18% |
| May 15 | 72°F | 41°F | 31% | 18% |
| May 22 | 75°F | 44°F | 33% | 18% |
| May 31 | 78°F | 47°F | 33% | 18% |
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 | 67°F | 36°F | 28% | 18% | 13 h 50 min |
| May 2 | 67°F | 36°F | 28% | 18% | 13 h 50 min |
| May 3 | 68°F | 37°F | 28% | 18% | 14 h |
| May 4 | 68°F | 37°F | 29% | 18% | 14 h |
| May 5 | 69°F | 37°F | 29% | 18% | 14 h |
| May 6 | 69°F | 38°F | 29% | 18% | 14 h |
| May 7 | 69°F | 38°F | 29% | 18% | 14 h 10 min |
| May 8 | 70°F | 39°F | 29% | 18% | 14 h 10 min |
| May 9 | 70°F | 39°F | 30% | 18% | 14 h 10 min |
| May 10 | 70°F | 39°F | 30% | 18% | 14 h 10 min |
| May 11 | 71°F | 40°F | 30% | 18% | 14 h 10 min |
| May 12 | 71°F | 40°F | 30% | 18% | 14 h 20 min |
| May 13 | 72°F | 40°F | 31% | 18% | 14 h 20 min |
| May 14 | 72°F | 41°F | 31% | 18% | 14 h 20 min |
| May 15 | 72°F | 41°F | 31% | 18% | 14 h 20 min |
| May 16 | 73°F | 42°F | 31% | 18% | 14 h 20 min |
| May 17 | 73°F | 42°F | 32% | 18% | 14 h 30 min |
| May 18 | 74°F | 42°F | 32% | 18% | 14 h 30 min |
| May 19 | 74°F | 43°F | 32% | 18% | 14 h 30 min |
| May 20 | 74°F | 43°F | 32% | 18% | 14 h 30 min |
| May 21 | 75°F | 43°F | 32% | 18% | 14 h 30 min |
| May 22 | 75°F | 44°F | 33% | 18% | 14 h 30 min |
| May 23 | 75°F | 44°F | 33% | 18% | 14 h 40 min |
| May 24 | 76°F | 44°F | 33% | 18% | 14 h 40 min |
| May 25 | 76°F | 45°F | 33% | 18% | 14 h 40 min |
| May 26 | 77°F | 45°F | 33% | 18% | 14 h 40 min |
| May 27 | 77°F | 45°F | 33% | 18% | 14 h 40 min |
| May 28 | 77°F | 46°F | 33% | 18% | 14 h 40 min |
| May 29 | 78°F | 46°F | 33% | 18% | 14 h 50 min |
| May 30 | 78°F | 46°F | 33% | 18% | 14 h 50 min |
| May 31 | 78°F | 47°F | 33% | 18% | 14 h 50 min |
- Normal high
- 73°FMay average
- Normal low
- 41°FMay average
- Precipitation
- 1.97 inmonth total
- Days with precipitation
- 100.01 inch or more
- Days at 90°F or more
- 1
- Nights at 32°F or colder
- 3
- Daylight
- 13 h 50 min to 14 h 50 minMay 1 to May 31
- Days at 70°F or more
- 20
- Days at 80°F or more
- 10
- Sunshine
- 69%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USC00055116; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Longmont in May?
On a given May day the chance of 0.01 inch or more is 31% on average, highest around May 26 (33%). In all, 1.97 in falls on 10 days of a normal May.
In a normal May in Longmont, 1 days reach 90°F and 3 nights fall to freezing.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USC00055116.
What are the records for May in Longmont?
The warmest May temperature on this station's record (since 1893) is 100°F, on May 30, 2003; the coldest is 18°F, on May 5, 1917. The wettest May brought 7.00 in (1995); the snowiest, 8.0 inches (1979).
The May mean against the 1991-2020 normal of 57.1°F: 2021 57.1°F (at normal), 2022 59.0°F (+1.9), 2023 60.1°F (+3.0), 2024 57.7°F (+0.6), 2025 58.7°F (+1.6), 2026 58.3°F (+1.2). 5 of 6 ran warmer than normal.
| May | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 57.1°F | at normal | 3.97 in |
| 2022 | 59.0°F | +1.9°F | 2.20 in |
| 2023 | 60.1°F | +3.0°F | 6.50 in |
| 2024 | 57.7°F | +0.6°F | 0.53 in |
| 2025 | 58.7°F | +1.6°F | 2.94 in |
| 2026 | 58.3°F | +1.2°F | 2.79 in |
Source: records: ACIS, station USC00055116; recent months: ACIS, station USC00055116. Records and recent months use complete months only.
How does May in Longmont compare across Colorado?
Across the 125 places PlainClimate covers in Colorado, May normal highs run from 54°F in Leadville to 80°F in Lamar; Longmont's is 73°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.