Thomson, IL Live Doppler Radar
Live radar for Thomson, Carroll County: every NWS radar combined, rain, snow and ice colors, flash-flood risk, storm tracks and official warnings.
What weather hits Thomson?
Since 1996, the National Weather Service has logged damaging thunderstorm winds on 95 days in the Carroll forecast zone and Carroll County — the most common reported hazard around Thomson, mostly in June and July. Next come heavy snow & winter storms (82 days) and flash flooding (25 days).
| Hazard | Days reported | Most recent | Worst on record |
|---|---|---|---|
| Damaging thunderstorm winds | 95 | Apr 2026 | Jun 23, 1996 · $1.0 million damage |
| Heavy snow & winter storms | 82 | Nov 2025 | — |
| Flash flooding | 25 | Apr 2026 | Jul 24, 2010 · $10 million damage |
| Flooding | 18 | Jul 2024 | Apr 18, 2011 · $250,000 damage |
| Extreme cold & wind chill | 17 | Jan 2019 | — |
| High winds | 12 | Feb 2019 | May 4, 2003 · $1.0 million damage |
| Ice storms & sleet | 8 | Feb 2023 | — |
| Blizzards | 5 | Mar 2026 | — |
Source: NOAA NCEI Storm Events Database, 1996–2026 (the latest year is partial). A "day" is a date with at least one report in the Carroll forecast zone and Carroll County; damage is as reported, not adjusted for inflation.
How much snow does Thomson get?
A normal year brings about 33 inches of snow to Thomson, based on NOAA's 1991–2020 climate normals for the Mt Carroll weather station 10.8 miles away. The snowiest month is usually January (10.2 in).
| Oct | Nov | Dec | Jan | Feb | Mar | Apr | May |
|---|---|---|---|---|---|---|---|
| 0.4 | 1.7 | 8.8 | 10.2 | 7.9 | 3.6 | 0.8 | 0.0 |
Normal snowfall in inches. TALON Pro compares this season's snow at your location with these normals as winter goes on.
Which radars cover Thomson?
The closest NEXRAD Doppler radar is KDVN (Quad Cities, IA), about 35 miles southwest. Radar beams climb as they travel, so the height of the lowest scan over town decides how low in a storm the radar can see.
| Radar | Distance | Lowest beam over Thomson | View |
|---|---|---|---|
| KDVN Quad Cities, IA | 35 mi southwest | 2,200 ft | Excellent — the lowest scan sees close to the ground |
| KMKX Milwaukee/Sullivan, WI | 105 mi northeast | 10,400 ft | Limited — the beam overshoots the lowest part of storms |
| KLOT Chicago, IL | 108 mi east-southeast | 10,700 ft | Limited — the beam overshoots the lowest part of storms |
Beam height is the center of the 0.5° scan above the radar, with standard refraction. Mountains near a radar can block it further.
Tornado & hail history near Thomson
Since 1950, NOAA has recorded 101 tornadoes within 25 miles of Thomson, 18 of them EF2/F2 or stronger. Most came in June and May. The strongest was an F4 on April 11, 1965, which passed about 23 miles northwest of town and caused 1 death. The most recent was an EF0 on April 20, 2025, which touched down about 22 miles south-southwest of town.
Hail: 190 reports of 1-inch or larger hail within 25 miles since 1955, 16 of them 2 inches or more; the largest was 3.00-inch hail on June 25, 2024.
Source: NOAA Storm Prediction Center — tornadoes 1950–2025, hail 1955–2025. Distances are to each tornado's track; ratings before February 2007 use the original Fujita scale.
On TALON you get Thomson's live radar loop, rain/snow/ice colors, flash-flood risk, storm tracks with arrival times and NWS warnings free; close-up radar and rotation detection are part of TALON Pro.
Thomson radar FAQ
Where is the nearest weather radar to Thomson, IL?
KDVN (Quad Cities, IA), about 35 miles southwest. KMKX (Milwaukee/Sullivan, WI) is 105 miles away and also covers the area.
Does radar show snow in Thomson?
Yes. TALON colors snow blue, a rain–snow mix pink and freezing rain purple using NOAA's precipitation-type analysis. Over Thomson the lowest scan from KDVN is about 2,200 ft up.
Is TALON's radar for Thomson free?
Yes — the US radar loop, rain/snow/ice colors, flash-flood risk, storm tracks and NWS warnings are free in any browser. Close-up radar, rotation detection and longer forecasts are part of TALON Pro.
Should I rely on radar for my safety?
No app replaces official warnings. When the National Weather Service issues a warning for Thomson, follow it right away — see watch vs. warning.
Radar for nearby towns
- Fulton, IL radar 8 mi
- Savanna, IL radar 8 mi
- Mount Carroll, IL radar 11 mi
- Morrison, IL radar 14 mi
- Lanark, IL radar 17 mi
- Erie, IL radar 22 mi
- Prophetstown, IL radar 23 mi
- Sterling, IL radar 25 mi
- Rock Falls, IL radar 26 mi
- Port Byron, IL radar 27 mi