Accuracy · public

We show our work.

Every hail platform claims accuracy. We're the only one that publishes it — measured against National Weather Service ground reports, updated continuously, good numbers and bad.

detections independently confirmed by NWS ground reports — and counting.

Independent corroboration is the strongest evidence a hail claim can carry. It's the number we lead with — not a marketing “99% accurate.”

Radar vs. ground truth

How close is the radar size?

For every storm a trained NWS spotter reported, we compare the hail size our radar showed at that exact point to what the spotter measured on the ground. Like-for-like, no cherry-picking.

The calibration sample is still growing as ground reports land. The confirmation count above updates live; the size-accuracy breakdown publishes once the verified-pair sample is large enough to be meaningful.

Methodology

No black box.

What counts as “confirmed”?
A radar-detected hail cell whose swath contains an independent NWS Local Storm Report within ~30 minutes. Two independent observations of the same event — radar and a human on the ground.
How do you measure size accuracy?
We compare the radar's estimated hail size at the report's exact location against the size the spotter reported — not the storm's peak miles away. Apples to apples.
Why not just claim “99% accurate”?
Because it wouldn't be honest. Radar infers hail aloft; size estimates carry real uncertainty. We'd rather show the true numbers and win on verification and defensibility.
Where does the data come from?
NOAA MRMS, NEXRAD Level II dual-polarization radar, and NWS Local Storm Reports — all public, all citable in a claim.