Decatur weather in March

In March, Decatur sees average daytime highs of 52°F and overnight lows near 34°F, with 3.3 in of precipitation across 9.7 wet days and about 11.7 hours of daylight. It is the 8th-warmest and 7th-wettest month of the year here.

Highs climb over the month, from about 46°F in the first days to 57°F by the end. The sky is clear or mostly clear about 25% 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 18 min by month's end. Set against the rest of the year, March is Decatur's 9th-clearest and 2nd-windiest month. For the whole year in context, see Decatur's year-round climate.

Daytime high
52°
8th warmest
Overnight low
34°
4th coldest
Precipitation
3.3 in
9.7 wet days
Daylight
11 h 42 min
6:15 AM – 5:56 PM
Cloud cover
66%
9th clearest
Wind
10 mph
2nd windiest
Solar energy
4.09 kWh/m²
Travel score
2.7
out of 10

Decatur is city in Macon County, Illinois, United States.

Density
602/km²
people per km²
Founded
1823

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 46°F in the first days to 57°F by the end.

A typical March day in Decatur reaches about 52°F in the afternoon and slips back to 34°F overnight — a 18°F spread between the day's warmth and the night's chill. On most days the high lands between 37°F and 69°F. Set against its neighbours, March runs about 12°F warmer than February and about 12°F cooler than April.

20°40°60°80°151015202531
Avg high (°F)Avg low (°F)
14528
24628
34629
44729
54729
64730
74830
84831
94931
104931
115032
125032
135133
145133
155233
165234
175334
185335
195335
205435
215436
225536
235537
245537
255637
265637
275638
285738
295738
305839
315839

How March really feels in Decatur

Once humidity and wind are folded in, March averages 0 days that feel above 90°F and 29 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
29
wind chill below the day's low

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

Decatur weather by month

How March compares with the rest of the year at a glance. March is the 8th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan36° / 21°2.78.549.50.0
Feb40° / 24°2.37.53.410.40.2
Mar52° / 34°3.39.71.511.72.7
Apr64° / 44°4.611.80.3135.3
May73° / 55°4.813.2014.26.2
Jun82° / 64°4.310.9014.86.0
Jul84° / 67°3.610.3014.55.5
Aug83° / 65°3.08.5013.66.1
Sep78° / 57°3.27.4012.37.3
Oct65° / 46°3.58.60.110.96.2
Nov51° / 35°3.58.70.89.82.7
Dec40° / 26°2.58.72.99.20.2

Cloud cover in March

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 25% of the time in March.

Beyond those clear spells, partly cloudy skies cover about 13% of March, with mostly cloudy or overcast conditions the remaining 62%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13763
23763
33763
43763
53862
63862
73862
83862
93961
103961
113961
123961
133862
143961
153862
163862
173961
183862
193862
203862
213862
223763
233763
243763
253763
263862
273862
283763
293862
303961
313961

Chance of precipitation in March

Any precipitationSnow

Decatur gets around 3.3 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 35% on the wettest days, and about 2 days bring snow. The odds climb toward the end of the month.

0%10%20%30%40%50%151015202531
Rain chance (%)Snow chance (%)
12910
2299
3299
4298
5288
6288
7287
8287
9276
10276
11286
12286
13286
14295
15305
16305
17315
18325
19325
20334
21334
22344
23344
24353
25353
26353
27353
28353
29352
30352
31352

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 97% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)
19910
29910
39910
49910
59910
69910
79910
89820
99820
109820
119820
129730
139730
149730
159730
169730
179640
189640
199640
209640
219640
229640
239550
249550
259550
269550
279550
289550
299451
309361
319361

Wind in March

Winds average 10 mph in March.

Across March, daily wind ranges from about 10 mph on the calmest days to 10 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
110light breeze
210light breeze
310light breeze
410light breeze
510light breeze
610light breeze
710light breeze
810light breeze
910light breeze
1010light breeze
1110light breeze
1210light breeze
1310light breeze
1410light breeze
1510light breeze
1610light breeze
1710light breeze
1810light breeze
1910light breeze
2010light breeze
2110light breeze
2210light breeze
2310light breeze
2410light breeze
2510light breeze
2610light breeze
2710light breeze
2810light breeze
2910light breeze
3010light breeze
3110light breeze

Sunrise & sunset in March

DaylightNight

Daylight runs from about 11 hours at the start of March to 12 h 18 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 78 minutes over March. Sunrise moves from 6:39 AM to 5:50 AM, and sunset from 5:40 PM to 6:11 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.06:395:40
211.16:375:41
311.16:365:42
411.16:345:43
511.26:335:44
611.26:315:45
711.36:305:46
811.36:285:47
911.46:265:48
1011.46:255:49
1111.56:235:50
1211.56:225:51
1311.56:205:53
1411.66:185:54
1511.66:175:55
1611.76:155:56
1711.76:145:57
1811.86:125:58
1911.86:105:59
2011.96:096:00
2111.96:076:01
2211.96:056:02
2312.06:046:03
2412.06:026:04
2512.16:006:05
2612.15:596:06
2712.25:576:07
2812.25:556:08
2912.35:546:09
3012.35:526:10
3112.35:506:11

Solar energy in March

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in March, about 4.09 kWh/m².

For context, solar energy here swings from a low near 1.8 kWh/m² to a high of 6.44 kWh/m² in June across the year — March's 4.09 kWh/m² falls in the middle.

024151015202531
Solar energy (kWh/m²)Level
13.6Moderate
23.6Moderate
33.7Moderate
43.7Moderate
53.8Moderate
63.8Moderate
73.8Moderate
83.9Moderate
93.9Moderate
104.0Moderate
114.0Moderate
124.0Bright
134.0Bright
144.1Bright
154.1Bright
164.1Bright
174.2Bright
184.2Bright
194.2Bright
204.2Bright
214.3Bright
224.3Bright
234.3Bright
244.3Bright
254.4Bright
264.4Bright
274.5Bright
284.5Bright
294.5Bright
304.6Bright
314.6Bright
Planning a trip in March

Hazard calendar for Decatur

In seasonPeak

None of Decatur's seasonal hazards are active in March. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Decatur sits in the Atlantic hurricane belt; the season peaks August–October.

Atlantic hurricane
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is March a good time to visit Decatur?

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

2.7
Sightseeing
8th-best month of the year
0.0
Beach & pool
8th-best month of the year

March is a weaker month for outdoor sightseeing in Decatur.

What to pack for Decatur in March

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

In March, Decatur sees daytime highs around 52°F and nights near 34°F. Pack a warm layer. Worth having: rain gear. About 10 days see rain.

a warm layerrain gear

UV index in Decatur in March

LowModerateHighVery highExtreme

Clear-sky midday UV in March peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Decatur peaks around June 22 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateJun 22UV 9Jan 1UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May8Very high
Jun9Very high
Jul9Very high
Aug8Very high
Sep6High
Oct4Moderate
Nov3Moderate
Dec2Low

Air quality in Decatur 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 Decatur is worst in July — around 17 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (October, 8 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodModerateGoodJul 1716 µg/m³Oct 228 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb13Moderate
Mar12Moderate
Apr11Good
May14Moderate
Jun14Moderate
Jul17Moderate
Aug15Moderate
Sep12Good
Oct8Good
Nov8Good
Dec9Good
Location & terrain

Where is Decatur?

Decatur sits at 39.8°N, 89.0°W, 673 ft above sea level, in United States. The nearest listed city is Springfield, 37 mi away.

Topography around Decatur

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

Within 2 miles, the terrain around Decatur has only modest variations in elevation — a maximum elevation change of 164 ft around an average of 666 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 197 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 489 ft.

The land around Decatur is covered by trees (43%) and artificial surfaces (34%) within 2 miles, cropland (68%) within 10 miles, and cropland (83%) within 50 miles.

2 miles
164 ft
10 miles
197 ft
50 miles
489 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
March weather nearby: Springfield 37 mi · Mattoon 40 mi · Champaign 42 mi · Urbana 43 mi · Bloomington 45 mi · Normal 47 mi · Charleston 48 mi · Morton 60 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 Decatur (39.8403°, -88.9548°, elevation 673 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). 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).