Climate Sullivan - Illinois
| JanJa | FebFe | MarMa | AprAp | MayMa | JunJu | |
|---|---|---|---|---|---|---|
| Average high in ºF Av. high Hi | 35 | 39 | 50 | 63 | 73 | 83 |
| Average low in ºF Av. low Lo | 18 | 21 | 31 | 40 | 51 | 61 |
| Av. precipitation in inch Av. precip. Pre. | 2.38 | 2.18 | 2.59 | 3.67 | 4.50 | 4.44 |
| Av. snowfall in inch Snowfall Sn | 6 | 3 | 1 | 0 | 0 | 0 |
| JulJu | AugAu | SepSe | OctOc | NovNo | DecDe | |
|---|---|---|---|---|---|---|
| Average high in ºF Av. high Hi | 85 | 85 | 77 | 66 | 51 | 38 |
| Average low in ºF Av. low Lo | 65 | 61 | 53 | 42 | 32 | 22 |
| Av. precipitation in inch Av. precip. Pre. | 4.34 | 3.06 | 2.61 | 3.25 | 3.60 | 3.15 |
| Av. snowfall in inch Snowfall Sn | 0 | 0 | 0 | 0 | 0 | 3 |
What is the average weather in Sullivan, Illinois?
Sullivan experiences a humid continental climate, marked by a very large seasonal temperature contrast. Summers are warm and fairly wet, with precipitation spread relatively evenly throughout the year. Winters are cold and bring regular snowfall, with winter being the driest season overall.
Sullivan Climate Graph - Illinois Climate Chart
Daily normals Sullivan - Illinois - January
Day | High ºF | Low ºF | Prec/mo inch | Prec/yr inch | Snow/mo inch | Snow/yr inch |
|---|---|---|---|---|---|---|
| 1 Jan | 35.1 | 19.7 | 0.08 | 0.08 | 0.12 | 0.30 |
| 2 Jan | 35.0 | 19.5 | 0.20 | 0.20 | 0.31 | 0.80 |
| 3 Jan | 34.9 | 19.4 | 0.28 | 0.28 | 0.39 | 1.00 |
| 4 Jan | 34.8 | 19.2 | 0.35 | 0.35 | 0.51 | 1.30 |
| 5 Jan | 34.7 | 19.1 | 0.47 | 0.47 | 0.71 | 1.80 |
| 6 Jan | 34.6 | 18.9 | 0.55 | 0.55 | 0.91 | 2.30 |
| 7 Jan | 34.5 | 18.8 | 0.63 | 0.63 | 0.98 | 2.50 |
| 8 Jan | 34.4 | 18.6 | 0.71 | 0.71 | 1.18 | 3.00 |
| 9 Jan | 34.3 | 18.5 | 0.79 | 0.79 | 1.42 | 3.60 |
| 10 Jan | 34.3 | 18.3 | 0.87 | 0.87 | 1.50 | 3.80 |
| 11 Jan | 34.2 | 18.2 | 0.94 | 0.94 | 1.69 | 4.30 |
| 12 Jan | 34.2 | 18.1 | 1.02 | 1.02 | 1.81 | 4.60 |
| 13 Jan | 34.1 | 17.9 | 1.10 | 1.10 | 2.01 | 5.10 |
| 14 Jan | 34.1 | 17.8 | 1.18 | 1.18 | 2.20 | 5.60 |
| 15 Jan | 34.1 | 17.7 | 1.22 | 1.22 | 2.40 | 6.10 |
| 16 Jan | 34.1 | 17.6 | 1.34 | 1.34 | 2.60 | 6.60 |
| 17 Jan | 34.1 | 17.5 | 1.42 | 1.42 | 2.80 | 7.10 |
| 18 Jan | 34.1 | 17.4 | 1.50 | 1.50 | 2.99 | 7.60 |
| 19 Jan | 34.1 | 17.3 | 1.57 | 1.57 | 3.19 | 8.10 |
| 20 Jan | 34.2 | 17.2 | 1.61 | 1.61 | 3.50 | 8.90 |
| 21 Jan | 34.2 | 17.1 | 1.69 | 1.69 | 3.70 | 9.40 |
| 22 Jan | 34.3 | 17.1 | 1.77 | 1.77 | 3.90 | 9.90 |
| 23 Jan | 34.3 | 17.1 | 1.81 | 1.81 | 4.09 | 10.40 |
| 24 Jan | 34.4 | 17.0 | 1.89 | 1.89 | 4.41 | 11.20 |
| 25 Jan | 34.5 | 17.0 | 1.97 | 1.97 | 4.61 | 11.70 |
| 26 Jan | 34.6 | 17.0 | 2.05 | 2.05 | 4.80 | 12.20 |
| 27 Jan | 34.7 | 17.1 | 2.13 | 2.13 | 5.12 | 13.00 |
| 28 Jan | 34.9 | 17.1 | 2.17 | 2.17 | 5.31 | 13.50 |
| 29 Jan | 35.0 | 17.2 | 2.24 | 2.24 | 5.51 | 14.00 |
| 30 Jan | 35.1 | 17.2 | 2.32 | 2.32 | 5.71 | 14.50 |
| 31 Jan | 35.3 | 17.3 | 2.36 | 2.36 | 5.91 | 15.00 |
Weather history Sullivan - January 2026
| Day | High ºF | Low ºF | Precip. inch | Snow inch | Snow d. inch |
|---|---|---|---|---|---|
| 01 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 02 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 03 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 04 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 05 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 06 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 07 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 08 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 09 Jan | - | - | 0.92 | 0.00 | 0.0 |
| 10 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 11 Jan | - | - | T | T | T |
| 12 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 13 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 14 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 15 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 16 Jan | - | - | - | - | - |
| 17 Jan | - | - | - | - | - |
| 18 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 19 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 20 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 21 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 22 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 23 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 24 Jan | - | - | 0.00 | 0.00 | 0.0 |
| 25 Jan | - | - | - | - | - |
| 26 Jan | - | - | - | - | - |
| 27 Jan | - | - | 0.00 | 0.00 | - |
| 28 Jan | - | - | 0.00 | 0.00 | - |
| 29 Jan | - | - | 0.00 | 0.00 | - |
| 30 Jan | - | - | 0.00 | 0.00 | - |
| 31 Jan | - | - | 0.00 | 0.00 | - |
Past weather Sullivan
| Jan 26 | Normal | ||
|---|---|---|---|
| Average high temperature Av. high temp. | - ºF | 35 ºF | |
| Average low temperature Av. low temp. | - ºF | 18 ºF | |
| Total precipitation Total precip. | 0.92 inch | 2.38 inch | |
| Total snowfall Total snowfall | 0.00 inch | 6 inch | |
| Highest max temperature Highest max temp. | - ºF | - | |
| Lowest max temperature Lowest max temp. | - ºF | - | |
| Highest min temperature Highest min temp. | - ºF | - | |
| Lowest min temperature Lowest min temp. | - ºF | - | |
Past weather January 2026 incomplete - Missing data
Geo Sullivan - Illinois
| Country | United States | |
|---|---|---|
| State | Illinois | |
| County | - | |
| City | Sullivan | |
| Zip Code | 61951 | |
| Longitude | -88.61 dec. degr. | |
| Latitude | 39.6 dec. degr. | |
| Altitude - Elevation | 673ft | |
| ICAO | - | |
| IATA | - |
Date and Time Sullivan - Illinois
| Local Time | 12:20 PM | |
|---|---|---|
| Sunrise | 05:30 AM | |
| Sunset | 08:27 PM | |
| Day/Night | Day | |
| Timezone | Central Daylight Time | |
| Timezone DB | America - Chicago |
Map of Sullivan - Illinois
USGS National Map — Open interactive map
Sullivan weather averages
| Annual high temperature | 62ºF |
| Annual low temperature | 42ºF |
| Average annual precip. | 39.77 inch |
| Av. annual snowfall | 13 inch |
Station Data
Monthly averages Sullivan
Longitude: -88.6078, Latitude: 39.5995
Average weather Sullivan, IL - 61951
Monthly: 1991-2020 normals
History: 2008-2026
Abbreviations
Average precipitation in : Av. precipitation in
Jan: January, Feb: February, ...Jan: January, Feb: February, ...Ja: January, Fe: February, ...