KATX radar — Seattle/Tacoma, WA
KATX is the National Weather Service's WSR-88D Doppler radar for the Seattle/Tacoma area, operated with the NWS office SEW. View it live in TALON — the loop, super-res reflectivity, storm-relative velocity, rotation and correlation coefficient.
| Station | KATX (Seattle/Tacoma, Washington) |
|---|---|
| Location | 48.1950°, -122.4960° · Island County |
| Elevation | 640 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 KATX see?
A radar beam travels in a nearly straight line while the Earth curves away underneath it, so the farther a storm is from KATX, 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 KATX | 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 KATX's range
Since 1950, NOAA has recorded 16 tornadoes within 60 miles of the KATX radar, 4 of them rated EF2/F2 or stronger. They have been most common in December and June. The strongest was an F3 on December 12, 1969, which passed about 47 miles south of the radar. The most recent was an EF2 on December 18, 2018, which touched down about 47 miles south of the radar.
Hail: 3 reports of hail 1 inch or larger within 60 miles of the KATX radar since 1955. The largest was 1.50-inch hail (ping pong ball size) on June 8, 1972.
| Tornadoes since 1950 | 16 |
| EF2/F2 or stronger | 4 |
| Strongest tornado | F3 · Dec 1969 |
| Busiest tornado month | December |
| Largest hail | 1.50 in · Jun 1972 |
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.
Nearby radars
- KLGX · Langley Hill, WA 106 mi
- KRTX · Portland, OR 173 mi
- KOTX · Spokane, WA 228 mi
- KPDT · Pendleton, OR 244 mi
- KMSX · Missoula, MT 404 mi
KATX radar FAQ
How often does KATX 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 KATX?
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 KATX down?
Radars occasionally go offline for maintenance. When one does, TALON's US radar map fills the gap from neighboring radars (KLGX, KRTX, KOTX).