Longmont weather in March

In March, Longmont sees average daytime highs of 54°F and overnight lows near 27°F, with 1.6 in of precipitation across 7.3 wet days and about 11.7 hours of daylight. It is the 8th-warmest and 5th-wettest month of the year here.

Highs climb over the month, from about 49°F in the first days to 57°F by the end. The sky is clear or mostly clear about 37% of the time in March, and the air most often feels dry.

Daylight stretches from about 11 hours at the start of March to 12 h 24 min by month's end. Set against the rest of the year, March is Longmont's 9th-clearest and 2nd-windiest month. For the whole year in context, see Longmont's year-round climate.

Daytime high
54°
8th warmest
Overnight low
27°
5th coldest
Precipitation
1.6 in
7.3 wet days
Daylight
11 h 42 min
6:20 AM – 6:00 PM
Cloud cover
51%
9th clearest
Wind
5 mph
2nd windiest
Solar energy
5.15 kWh/m²
Travel score
3.6
out of 10

Longmont is city in Boulder County, Colorado, United States.

Density
1,228/km²
people per km²
Founded
1871

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in March

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 49°F in the first days to 57°F by the end.

A typical March day in Longmont reaches about 54°F in the afternoon and slips back to 27°F overnight — a 27°F spread between the day's warmth and the night's chill. On most days the high lands between 38°F and 69°F. Set against its neighbours, March runs about 10°F warmer than February and about 7°F cooler than April.

20°40°60°80°151015202531
Avg high (°F)Avg low (°F)
14823
24923
34924
45024
55024
65124
75125
85225
95226
105326
115326
125327
135427
145427
155528
165528
175528
185528
195528
205629
215629
225629
235629
245629
255630
265630
275730
285730
295730
305731
315831

How March really feels in Longmont

Once humidity and wind are folded in, March averages 0 days that feel above 90°F and 31 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
31
wind chill below the day's low

The story in March is cold — wind chill drags the overnight "feels like" below the raw low.

Longmont weather by month

How March compares with the rest of the year at a glance. March is the 8th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan41° / 18°0.84.74.59.50.1
Feb44° / 20°0.85.3510.41.0
Mar54° / 27°1.67.34.411.73.6
Apr61° / 35°2.69.54135.0
May69° / 44°3.411.70.614.26.2
Jun80° / 53°2.18.5014.86.6
Jul86° / 59°1.77.4014.65.3
Aug84° / 57°1.66.8013.66.1
Sep76° / 49°1.55.90.412.37.6
Oct63° / 37°1.66.51.910.96.2
Nov50° / 27°1.15.84.49.82.7
Dec41° / 19°0.74.54.49.20.2

Cloud cover in March

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 37% of the time in March.

Beyond those clear spells, partly cloudy skies cover about 20% of March, with mostly cloudy or overcast conditions the remaining 43%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16040
26040
36040
46040
56139
66139
76139
86040
96040
106040
115941
125941
135941
145842
155842
165644
175644
185644
195446
205446
215446
225446
235347
245347
255347
265347
275347
285347
295347
305248
315248

Chance of precipitation in March

Any precipitationSnow

Longmont gets around 1.6 in of rain and snow over 7.3 wet days in March. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 23% and peaks near 30% on the wettest days, and about 4 days bring snow. The odds climb toward the end of the month.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
12116
22016
32016
42015
52015
61915
71914
81914
91914
101913
111913
122013
132013
142013
152113
162113
172213
182313
192313
202413
212514
222614
232714
242815
252915
262915
272916
283016
293016
303016
313016

Humidity in March

DryComfortableHumidMuggyOppressiveMiserable

Most of March feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, March lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
17100
18100
19100
20100
21100
22100
23100
24100
25100
26100
27100
28100
29100
30100
31100

Wind in March

Winds average 5 mph in March.

Across March, daily wind ranges from about 5 mph on the calmest days to 5 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm
315calm

Sunrise & sunset in March

DaylightNight

Daylight runs from about 11 hours at the start of March to 12 h 24 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 84 minutes over March. Sunrise moves from 6:44 AM to 5:55 AM, and sunset from 5:44 PM to 6:16 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.06:445:44
211.06:425:45
311.16:415:46
411.16:395:47
511.26:375:48
611.26:365:49
711.36:345:50
811.36:335:52
911.46:315:53
1011.46:305:54
1111.46:285:55
1211.56:265:56
1311.56:255:57
1411.66:235:58
1511.66:225:59
1611.76:206:00
1711.76:186:01
1811.86:176:02
1911.86:156:03
2011.96:136:04
2111.96:126:05
2211.96:106:07
2312.06:086:08
2412.06:076:09
2512.16:056:10
2612.16:036:11
2712.26:026:12
2812.26:006:13
2912.35:586:14
3012.35:576:15
3112.45:556:16

Solar energy in March

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in March, about 5.15 kWh/m².

For context, solar energy here swings from a low near 2.42 kWh/m² to a high of 7.36 kWh/m² in June across the year — March's 5.15 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
14.5Bright
24.5Bright
34.6Bright
44.7Bright
54.7Bright
64.7Bright
74.8Bright
84.8Bright
94.9Bright
104.9Bright
115.0Bright
125.0Bright
135.0Bright
145.1Bright
155.1Bright
165.2Bright
175.2Bright
185.2Bright
195.3Bright
205.3Bright
215.3Bright
225.4Bright
235.4Bright
245.5Bright
255.5Bright
265.5Bright
275.5Bright
285.6Bright
295.6Bright
305.7Bright
315.7Bright
Planning a trip in March

Is March a good time to visit Longmont?

Our two travel scores rate March for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

3.6
Sightseeing
8th-best month of the year
0.0
Beach & pool
9th-best month of the year

March is a weaker month for outdoor sightseeing in Longmont.

What to pack for Longmont in March

From March's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In March, Longmont sees daytime highs around 54°F and nights near 27°F. Worth packing: a warm layer and sun protection. About 7 days see rain.

a warm layersun protection

UV index in Longmont in March

LowModerateHighVery highExtreme

Clear-sky midday UV in March peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Longmont peaks around July 13 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 23 at about 2 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJul 13UV 11Dec 23UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar7High
Apr6High
May7Very high
Jun11Extreme
Jul11Extreme
Aug10Very high
Sep7Very high
Oct5High
Nov3Moderate
Dec2Low

Air quality in Longmont in March

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where March falls, not just the annual average.

Air quality in Longmont is worst in October — around 30 µg/m³ PM2.5 (moderate), about 3.1× the cleanest month (November, 10 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

010203040JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodModerateGoodOct 1528 µg/m³Nov 2310 µg/m³
PM2.5 (µg/m³)Level
Jan12Good
Feb12Moderate
Mar14Moderate
Apr11Good
May11Good
Jun12Good
Jul14Moderate
Aug19Moderate
Sep17Moderate
Oct30Moderate
Nov10Good
Dec11Good
Location & terrain

Where is Longmont?

Longmont sits at 40.2°N, 105.1°W, 4,984 ft above sea level, in United States. The nearest listed city is Erie, 8.7 mi away.

Topography around Longmont

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Longmont.

Within 2 miles, the terrain around Longmont has only modest variations in elevation — a maximum elevation change of 197 ft around an average of 4,993 ft above sea level; within 10 miles, significant variations in elevation — a maximum elevation change of 1,765 ft; within 50 miles, extreme variations in elevation — a maximum elevation change of 9,721 ft.

The land around Longmont is covered by artificial surfaces (50%) and trees (22%) within 2 miles, grassland (54%) and cropland (25%) within 10 miles, and grassland (42%) and trees (31%) within 50 miles.

2 miles
197 ft
10 miles
1,765 ft
50 miles
9,721 ft
treesgrasslandcroplandartificial surfacesbare terrainwatermoss and lichen
March weather nearby: Erie 8.7 mi · Lafayette 12 mi · Louisville 13 mi · Boulder 14 mi · Loveland 16 mi · Broomfield 17 mi · Brighton 19 mi · Northglenn 21 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Longmont (40.1672°, -105.1019°, elevation 4,984 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).