KMRX radar — Knoxville, TN
KMRX is the National Weather Service's WSR-88D Doppler radar for the Knoxville area, operated with the NWS office MRX. View it live in TALON — the loop, super-res reflectivity, storm-relative velocity, rotation and correlation coefficient.
| Station | KMRX (Knoxville, Tennessee) |
|---|---|
| Location | 36.1680°, -83.4020° · Hamblen County |
| Elevation | 1,434 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 KMRX see?
A radar beam travels in a nearly straight line while the Earth curves away underneath it, so the farther a storm is from KMRX, 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 KMRX | 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 KMRX's range
Since 1950, NOAA has recorded 158 tornadoes within 60 miles of the KMRX radar, 35 of them rated EF2/F2 or stronger. They have been most common in April and May. The strongest was an EF4 on April 27, 2011, which passed about 43 miles southwest of the radar. The most recent was an EF1 on May 20, 2025, which touched down about 57 miles west-southwest of the radar.
Hail: 971 reports of hail 1 inch or larger within 60 miles of the KMRX radar since 1955, 68 of them 2 inches or larger. The largest was 5.00-inch hail (grapefruit size) on April 23, 1968.
| Tornadoes since 1950 | 158 |
| EF2/F2 or stronger | 35 |
| Strongest tornado | EF4 · Apr 2011 |
| Busiest tornado month | April |
| Largest hail | 5.00 in · Apr 1968 |
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 KMRX
- Knoxville, TN 32 mi west-southwest
- Chattanooga, TN 132 mi southwest
- Lexington, KY 143 mi north-northwest
- Charlotte, NC 158 mi east-southeast
- Atlanta, GA 176 mi south-southwest
Nearby radars
- KJKL · Jackson, KY 98 mi
- KGSP · Greer, SC 111 mi
- KHTX · Huntsville, AL 173 mi
- KRLX · Charleston, WV 175 mi
- KOHX · Nashville, TN 176 mi
KMRX radar FAQ
How often does KMRX 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 KMRX?
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 KMRX down?
Radars occasionally go offline for maintenance. When one does, TALON's US radar map fills the gap from neighboring radars (KJKL, KGSP, KHTX).