KFSX radar — Flagstaff, AZ
KFSX is the National Weather Service's WSR-88D Doppler radar for the Flagstaff area, operated with the NWS office FGZ. View it live in TALON — the loop, super-res reflectivity, storm-relative velocity, rotation and correlation coefficient.
| Station | KFSX (Flagstaff, Arizona) |
|---|---|
| Location | 34.5740°, -111.1980° · Coconino County |
| Elevation | 7,513 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 KFSX see?
A radar beam travels in a nearly straight line while the Earth curves away underneath it, so the farther a storm is from KFSX, 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 KFSX | 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 KFSX's range
Since 1950, NOAA has recorded 42 tornadoes within 60 miles of the KFSX radar, 6 of them rated EF2/F2 or stronger. They have been most common in October and September. The strongest was an EF3 on October 6, 2010, which passed about 50 miles northwest of the radar. The most recent was an EF0 on July 26, 2024, which touched down about 57 miles east of the radar.
Hail: 158 reports of hail 1 inch or larger within 60 miles of the KFSX radar since 1955, 15 of them 2 inches or larger. The largest was 4.50-inch hail (grapefruit size) on September 28, 1995.
| Tornadoes since 1950 | 42 |
| EF2/F2 or stronger | 6 |
| Strongest tornado | EF3 · Oct 2010 |
| Busiest tornado month | October |
| Largest hail | 4.50 in · Sep 1995 |
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
- KIWA · Phoenix, AZ 93 mi
- KEMX · Tucson, AZ 188 mi
- KESX · Las Vegas, NV 223 mi
- KICX · Cedar City, UT 228 mi
- KYUX · Yuma, AZ 246 mi
KFSX radar FAQ
How often does KFSX 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 KFSX?
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 KFSX down?
Radars occasionally go offline for maintenance. When one does, TALON's US radar map fills the gap from neighboring radars (KIWA, KEMX, KESX).