McHenry weather in March

In March, McHenry sees average daytime highs of 45°F and overnight lows near 29°F, with 2.5 in of precipitation across 9.7 wet days and about 11.6 hours of daylight. It is the 9th-warmest and 8th-wettest month of the year here.

Highs climb over the month, from about 39°F in the first days to 51°F by the end. The sky is clear or mostly clear about 23% of the time in March, and the air most often feels dry.

Daylight stretches from about 10 h 54 min at the start of March to 12 h 24 min by month's end. Set against the rest of the year, March is McHenry's 8th-clearest and 5th-windiest month. For the whole year in context, see McHenry's year-round climate.

Daytime high
45°
9th warmest
Overnight low
29°
4th coldest
Precipitation
2.5 in
9.7 wet days
Daylight
11 h 36 min
6:13 AM – 5:52 PM
Cloud cover
66%
8th clearest
Wind
9 mph
5th windiest
Solar energy
4 kWh/m²
Travel score
1.1
out of 10

McHenry is city in Illinois, United States.

Density
684/km²
people per km²
Founded
1872

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 39°F in the first days to 51°F by the end.

A typical March day in McHenry reaches about 45°F in the afternoon and slips back to 29°F overnight — a 16°F spread between the day's warmth and the night's chill. On most days the high lands between 31°F and 61°F. Set against its neighbours, March runs about 11°F warmer than February and about 12°F cooler than April.

20°40°60°151015202531
Avg high (°F)Avg low (°F)
13824
23924
33924
43925
54025
64025
74126
84126
94226
104227
114327
124328
134428
144429
154529
164529
174630
184630
194731
204731
214731
224832
234832
244932
254933
264933
275033
285033
295134
305134
315134

How March really feels in McHenry

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.

McHenry weather by month

How March compares with the rest of the year at a glance. March is the 9th-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan30° / 17°2.07.969.30.0
Feb34° / 20°1.975.210.30.0
Mar45° / 29°2.59.73.311.61.1
Apr57° / 39°4.312.31.113.13.7
May68° / 50°4.312.2014.45.9
Jun78° / 61°3.811.80156.4
Jul82° / 65°3.410.4014.86.4
Aug80° / 63°3.610.6013.76.6
Sep73° / 55°3.08.8012.37.0
Oct60° / 44°3.08.70.210.85.0
Nov46° / 33°2.47.81.69.61.4
Dec35° / 22°2.184.690.0

Cloud cover in March

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 23% of the time in March.

Beyond those clear spells, partly cloudy skies cover about 14% of March, with mostly cloudy or overcast conditions the remaining 63%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13664
23664
33763
43763
53862
63862
73862
83961
93961
103961
114060
124060
134060
144060
154060
163961
173961
184060
193961
203862
213862
223763
233565
243565
253466
263466
273466
283367
293367
303367
313367

Chance of precipitation in March

Any precipitationSnow

McHenry gets around 2.5 in of rain and snow over 9.7 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 31% and peaks near 36% on the wettest days, and about 3 days bring snow.

0%10%20%30%40%50%151015202531
Rain chance (%)Snow chance (%)
13018
23017
33017
43016
53016
63015
73014
83014
93013
103013
113012
122912
132911
142911
152911
162910
173010
18309
19309
20309
21318
22318
23328
24337
25337
26346
27346
28356
29355
30365
31365

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 99% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
11000
21000
31000
41000
51000
61000
71000
81000
91000
101000
11991
12991
13991
14991
15991
16991
17991
18982
19982
20982
21982
22982
23982
24982
25982
26982
27982
28982
29982
30982
31982

Wind in March

Winds average 9 mph in March.

Across March, daily wind ranges from about 8 mph on the calmest days to 9 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
19light breeze
29light breeze
39light breeze
49light breeze
59light breeze
69light breeze
79light breeze
89light breeze
99light breeze
109light breeze
119light breeze
129light breeze
139light breeze
149light breeze
159light breeze
169light breeze
179light breeze
189light breeze
198light breeze
208light breeze
218light breeze
228light breeze
238light breeze
248light breeze
258light breeze
269light breeze
279light breeze
289light breeze
299light breeze
309light breeze
319light breeze

Sunrise & sunset in March

DaylightNight

Daylight runs from about 10 h 54 min 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 90 minutes over March. Sunrise moves from 6:39 AM to 5:47 AM, and sunset from 5:34 PM to 6:09 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
110.96:395:34
211.06:375:35
311.06:355:36
411.16:345:38
511.16:325:39
611.26:305:40
711.26:295:41
811.36:275:43
911.36:255:44
1011.46:245:45
1111.46:225:46
1211.56:205:47
1311.56:195:49
1411.56:175:50
1511.66:155:51
1611.66:135:52
1711.76:125:53
1811.76:105:54
1911.86:085:56
2011.86:065:57
2111.96:055:58
2211.96:035:59
2312.06:016:00
2412.05:596:01
2512.15:576:03
2612.15:566:04
2712.25:546:05
2812.25:526:06
2912.35:506:07
3012.35:486:08
3112.45:476:09

Solar energy in March

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in March, about 4 kWh/m².

For context, solar energy here swings from a low near 1.6 kWh/m² to a high of 6.32 kWh/m² in June across the year — March's 4 kWh/m² falls in the middle.

012345151015202531
Solar energy (kWh/m²)Level
13.4Moderate
23.5Moderate
33.5Moderate
43.6Moderate
53.6Moderate
63.7Moderate
73.7Moderate
83.8Moderate
93.8Moderate
103.8Moderate
113.9Moderate
123.9Moderate
134.0Moderate
144.0Moderate
154.0Bright
164.0Bright
174.1Bright
184.1Bright
194.1Bright
204.2Bright
214.2Bright
224.2Bright
234.2Bright
244.2Bright
254.3Bright
264.3Bright
274.3Bright
284.3Bright
294.4Bright
304.4Bright
314.4Bright
Planning a trip in March

Is March a good time to visit McHenry?

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

1.1
Sightseeing
9th-best month of the year
0.0
Beach & pool
9th-best month of the year

March is a weaker month for outdoor sightseeing in McHenry.

What to pack for McHenry in March

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

In March, McHenry sees daytime highs around 45°F and nights near 29°F. Pack a warm layer and a heavy coat. Worth having: rain gear. About 10 days see rain.

a warm layera heavy coatrain gear

Sea temperature near McHenry in March

The nearest coast averages about 36°F in March — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 21 mi away) is warmest in August at about 71°F and coldest in March near 36°F.

It's comfortable for a long swim from Jul 18 to Sep 8 — about 1.7 months when the water holds above 68°F.

30°40°50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°F)Comfort
Jan38Bracing
Feb36Bracing
Mar36Bracing
Apr38Bracing
May43Bracing
Jun55Bracing
Jul68Refreshing
Aug71Refreshing
Sep67Cool
Oct57Bracing
Nov47Bracing
Dec42Bracing

UV index in McHenry in March

LowModerateHighVery highExtreme

Clear-sky midday UV in March peaks around 4 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in McHenry peaks around June 21 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 21UV 9Dec 21UV 1
UV index (midday)Level
Jan2Low
Feb2Moderate
Mar4Moderate
Apr6High
May8Very high
Jun9Very high
Jul8Very high
Aug8Very high
Sep6High
Oct3Moderate
Nov2Moderate
Dec1Low

Air quality in McHenry 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 McHenry is worst in July — around 17 µg/m³ PM2.5 (moderate), about 1.9× the cleanest month (October, 9 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodJul 1817 µg/m³Oct 229 µg/m³
PM2.5 (µg/m³)Level
Jan12Moderate
Feb15Moderate
Mar16Moderate
Apr14Moderate
May15Moderate
Jun16Moderate
Jul17Moderate
Aug16Moderate
Sep13Moderate
Oct9Good
Nov10Good
Dec11Good
Location & terrain

Where is McHenry?

McHenry sits at 42.3°N, 88.3°W, 797 ft above sea level, in United States. The nearest listed city is Crystal Lake, 6.8 mi away.

Topography around McHenry

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

Within 2 miles, the terrain around McHenry has only modest variations in elevation — a maximum elevation change of 128 ft around an average of 778 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 312 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 827 ft.

The land around McHenry is covered by trees (38%), artificial surfaces (26%) and grassland (21%) within 2 miles, trees (37%), grassland (27%) and cropland (20%) within 10 miles, and cropland (33%), trees (22%) and water (20%) within 50 miles.

2 miles
128 ft
10 miles
312 ft
50 miles
827 ft
treesgrasslandcroplandartificial surfaceswater
March weather nearby: Crystal Lake 6.8 mi · Cary 8.7 mi · Round Lake 8.7 mi · Woodstock 9.3 mi · Round Lake Beach 9.3 mi · Lake in the Hills 11 mi · Grayslake 12 mi · Algonquin 12 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 McHenry (42.3334°, -88.2668°, elevation 797 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. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).