KLSX radar — St. Louis, MO
KLSX is the National Weather Service's WSR-88D Doppler radar for the St. Louis area, operated with the NWS office LSX. View it live in TALON — the loop, super-res reflectivity, storm-relative velocity, rotation and correlation coefficient.
| Station | KLSX (St. Louis, Missouri) |
|---|---|
| Location | 38.6990°, -90.6830° · St. Charles County |
| Elevation | 719 ft above sea level |
| Type | WSR-88D (NEXRAD) S-band dual-polarization Doppler radar |
| Products in TALON | Super-res reflectivity (0.25 km), velocity, storm-relative velocity, rotation (azimuthal shear), correlation coefficient PRO |
How high can KLSX see?
A radar beam travels in a nearly straight line while the Earth curves away underneath it, so the farther a storm is from KLSX, the higher above the ground the radar is looking. Tornadoes start in the lowest few thousand feet, so storms close to the radar show low-level rotation much better.
| Distance from KLSX | Lowest scan (0.5°) | Next scan (1.5°) |
|---|---|---|
| 10 mi | 500 ft | 1,400 ft |
| 25 mi | 1,500 ft | 3,800 ft |
| 50 mi | 3,600 ft | 8,200 ft |
| 75 mi | 6,300 ft | 13,200 ft |
| 100 mi | 9,600 ft | 18,800 ft |
| 150 mi | 18,200 ft | 32,000 ft |
Height of the beam's center above the radar, using standard refraction. Terrain can raise or block the beam.
Severe weather inside KLSX's range
Since 1950, NOAA has recorded 550 tornadoes within 60 miles of the KLSX radar, 120 of them rated EF2/F2 or stronger. They have been most common in May and April. The strongest was an F4 on February 10, 1959, which passed about 13 miles south-southeast of the radar and caused 21 deaths. The most recent was an EF1 on June 18, 2025, which passed about 44 miles north-northwest of the radar.
Hail: 2,393 reports of hail 1 inch or larger within 60 miles of the KLSX radar since 1955, 259 of them 2 inches or larger. The largest was 4.50-inch hail (grapefruit size) on April 19, 2011.
| Tornadoes since 1950 | 550 |
| EF2/F2 or stronger | 120 |
| Strongest tornado | F4 · Feb 1959 |
| Busiest tornado month | May |
| Largest hail | 4.50 in · Apr 2011 |
Source: NOAA Storm Prediction Center severe weather database — tornadoes 1950–2025, hail 1955–2025 (the latest year is preliminary). Distances are to each tornado's recorded track; ratings before February 2007 use the original Fujita (F) scale.
Cities covered by KLSX
- St. Louis, MO 27 mi east
- Columbia, MO 91 mi west-northwest
- Springfield, IL 93 mi northeast
- Peoria, IL 150 mi north-northeast
- Springfield, MO 176 mi southwest
- Evansville, IN 176 mi east-southeast
Nearby radars
- KILX · Lincoln, IL 123 mi
- KPAH · Paducah, KY 153 mi
- KVWX · Evansville, IN 163 mi
- KSGF · Springfield, MO 179 mi
- KEAX · Kansas City, MO 193 mi
KLSX radar FAQ
How often does KLSX update?
Every NEXRAD radar completes a full scan about every 4–6 minutes in storm mode, and repeats the lowest tilt more often (SAILS) during severe weather. TALON loads each new scan as it arrives.
What is the range of KLSX?
Reflectivity reaches about 290 miles and velocity about 185 miles, but useful low-level detail is within roughly 100 miles — see the table above.
Is KLSX down?
Radars occasionally go offline for maintenance. When one does, TALON's US radar map fills the gap from neighboring radars (KILX, KPAH, KVWX).