Confirmed tracks first (strongest, then nearest), then early looks from scans still in progress. Not an official warning.
No open rotation tracks right now.
Ringed dots from scans still in progress. Hides early rotation on the map; strong and debris early looks always show. Early-look alert cards and notices always show.
Plays the last 30 minutes of scans, then holds on the latest. Expert mode adds a scrubber.
Replay: expert mode docks the scrubber at the bottom of the map.
Ringed dot and dashed trail: from the first tilts of the scan in progress, before it completes. The complete scan replaces it.
Trail colour shows the level the rotation had at that time.
Dashed line: projected path from the rotation's current motion. Bars every 10 min: how wide that path could be (wider = less certain). Projection only, not a guarantee.
A hollow dot is a track not seen on the latest scan. The arrow shows its heading. A dot with no line has no forecast yet (it needs 3 scans and some motion).
Checking your account…
Sign outDraws every projected path on the map (by default a weak, distant rotation shows only its dot and trail), docks a replay scrubber above the dock, adds the value probe (the ⊕ button on the map) and shows each track's full detail. Your choice is remembered on this device.
Off by default; remembered on this device. Alerts show only while this page is open.
Anvil finds rotation in NEXRAD radar scans and tracks it: ROTATION, STRONG ROTATION and DEBRIS CONFIRMED, each with a projected path. Radar images and tracks come from the same scans.
Experimental research product — not an official NWS warning.
Experimental research product — not an official NWS warning.