Hannibal weather in September

In September, Hannibal sees average daytime highs of 78°F and overnight lows near 58°F, with 3.3 in of rain across 7.6 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 5th-wettest month of the year here.

Highs ease over the month, from about 82°F in the first days to 73°F by the end. The sky is clear or mostly clear about 49% of the time in September, and the air most often feels dry.

Daylight stretches from about 12 h 54 min at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Hannibal's 1st-clearest and 10th-windiest month. For the whole year in context, see Hannibal's year-round climate.

Daytime high
78°
4th warmest
Overnight low
58°
9th coldest
Rainfall
3.3 in
7.6 wet days
Daylight
12 h 18 min
5:52 AM – 6:07 PM
Cloud cover
45%
1st clearest
Wind
7 mph
10th windiest
Solar energy
4.79 kWh/m²
Travel score
7.2
out of 10

Hannibal is city in Marion and Ralls counties in Missouri, United States.

Density
425/km²
people per km²
Founded
1819

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 82°F in the first days to 73°F by the end.

A typical September day in Hannibal reaches about 78°F in the afternoon and slips back to 58°F overnight — a 20°F spread between the day's warmth and the night's chill. On most days the high lands between 67°F and 88°F. Set against its neighbours, September runs about 7°F cooler than August and about 12°F warmer than October.

40°60°80°151015202530
Avg high (°F)Avg low (°F)
18364
28364
38263
48263
58262
68162
78162
88161
98061
108060
118060
127960
137959
147859
157858
167858
177758
187757
197757
207656
217656
227656
237555
247555
257454
267454
277454
287353
297353
307352

How September really feels in Hannibal

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

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Hannibal weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan36° / 21°2.07.249.50.0
Feb41° / 24°2.37.23.210.40.3
Mar53° / 34°3.110.11.811.72.9
Apr64° / 45°4.511.60.3135.4
May74° / 56°4.713.2014.26.3
Jun83° / 65°4.210.4014.85.8
Jul86° / 69°3.59.4014.55.1
Aug85° / 66°3.29.2013.65.6
Sep78° / 58°3.37.6012.37.2
Oct65° / 46°2.98.90.110.96.2
Nov52° / 35°3.17.91.19.82.9
Dec40° / 26°2.27.32.79.20.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 49% of the time in September, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 13% of September, with mostly cloudy or overcast conditions the remaining 38%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
16238
26436
36436
46337
56436
66436
76436
86436
96436
106337
116337
126238
136238
146139
156040
166040
176040
186040
196040
206040
216139
226040
236139
246139
256238
266238
276238
286238
296238
306238

Chance of precipitation in September

Any precipitation

Hannibal gets around 3.3 in of rain over 7.6 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 26% and peaks near 28% on the wettest days.

0%10%20%30%40%151015202530
Rain chance (%)
126
226
326
426
526
626
726
826
926
1026
1127
1227
1327
1427
1528
1628
1728
1827
1927
2027
2126
2226
2326
2425
2525
2624
2724
2824
2924
3024

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the dry band about 41% of days. Sticky, muggy-or-worse air turns up on roughly 21% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
11519242913
21620242812
31820242711
42021242610
5222223249
6232223238
7252323227
8272322216
9292322206
10312321205
11332320194
12352320194
13372319183
14392218183
15412218173
16422217162
17442216162
18462115152
19482115151
20502114141
21522013141
22532013131
23561912121
24571912111
25591911110
26611811100
2762181190
2863181090
2965171080
3065171080

Wind in September

Winds average 7 mph in September.

Across September, daily wind ranges from about 6 mph on the calmest days to 7 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (mph)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 54 min at the start of September to 11 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 78 minutes over September. Sunrise moves from 5:38 AM to 6:06 AM, and sunset from 6:33 PM to 5:44 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.95:386:33
212.95:396:31
312.85:406:29
412.85:416:28
512.75:426:26
612.75:426:24
712.75:436:23
812.65:446:21
912.65:456:19
1012.55:466:18
1112.55:476:16
1212.45:486:14
1312.45:496:13
1412.35:506:11
1512.35:516:09
1612.35:526:07
1712.25:536:06
1812.25:546:04
1912.15:556:02
2012.15:566:01
2112.05:575:59
2212.05:585:57
2311.95:595:56
2411.96:005:54
2511.96:015:52
2611.86:025:50
2711.86:035:49
2811.76:045:47
2911.76:055:45
3011.66:065:44

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.79 kWh/m².

For context, solar energy here swings from a low near 1.86 kWh/m² to a high of 6.45 kWh/m² in June across the year — September's 4.79 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.3Bright
25.3Bright
35.2Bright
45.2Bright
55.2Bright
65.1Bright
75.1Bright
85.0Bright
95.0Bright
105.0Bright
114.9Bright
124.9Bright
134.8Bright
144.8Bright
154.8Bright
164.7Bright
174.7Bright
184.6Bright
194.6Bright
204.6Bright
214.5Bright
224.5Bright
234.5Bright
244.4Bright
254.4Bright
264.3Bright
274.3Bright
284.3Bright
294.2Bright
304.2Bright
Planning a trip in September

Hazard calendar for Hannibal

In seasonPeak

In September, Hannibal sits inside its atlantic hurricane season. The full year is below, with each hazard's peak months called out.

Hannibal 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 September a good time to visit Hannibal?

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

7.2
Sightseeing
1st-best month of the year
6.6
Beach & pool
4th-best month of the year

September is one of the better times to visit Hannibal for general sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Hannibal in September

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

In September, Hannibal sees daytime highs around 78°F and nights near 58°F. Worth packing: light clothes and sun protection. About 8 days see rain.

light clothessun protection

UV index in Hannibal in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September 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 Hannibal peaks around June 21 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 2 (low).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highModerateJun 21UV 9Dec 22UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr7High
May8Very high
Jun9Very high
Jul9Very high
Aug8Very high
Sep7High
Oct4Moderate
Nov3Moderate
Dec2Low

Air quality in Hannibal in September

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Hannibal is worst in July — around 16 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (October, 7 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodGoodModerateGoodJul 1716 µg/m³Oct 237 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb12Moderate
Mar12Good
Apr10Good
May13Moderate
Jun14Moderate
Jul16Moderate
Aug14Moderate
Sep11Good
Oct7Good
Nov7Good
Dec8Good
Location & terrain

Where is Hannibal?

Hannibal sits at 39.7°N, 91.4°W, 502 ft above sea level, in United States. The nearest listed city is Quincy, 16 mi away.

Topography around Hannibal

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

Within 2 miles, the terrain around Hannibal has only modest variations in elevation — a maximum elevation change of 305 ft around an average of 558 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 430 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 702 ft.

The land around Hannibal is covered by trees (49%) within 2 miles, cropland (46%) and trees (32%) within 10 miles, and cropland (53%) and trees (32%) within 50 miles.

2 miles
305 ft
10 miles
430 ft
50 miles
702 ft
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Quincy 16 mi · Jacksonville 60 mi · Macomb 63 mi · Wentzville 68 mi · O'Fallon 71 mi · Kirksville 73 mi · Columbia 74 mi · Saint Peters 74 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 Hannibal (39.7084°, -91.3585°, elevation 502 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).