Wind radius

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Whole-season view — every storm's track at once, colored by peak intensity. Click any track to open that storm.

Live forecast mode. The gold marker replays the storm's whole life on one timeline — drag the slider or hit play. The past leg is JMA best-track (position, wind & the real storm-force wind radius per observation, via Digital Typhoon); from now on it's the JMA forecast — growing wind-radius circle, expected wind & Dvorak number, with violet probability circles (position uncertainty). Nothing here is simulated.

Season climatology — storms & energy by year, 1985–present

Points = named storms per season, each colored by that autumn's ENSO phase (El Niño La Niña Neutral). Purple line = seasonal ACE (accumulated cyclone energy). Click a point to jump to that season.

Track, intensity, and wind-radius data: IBTrACS v04r01 (NOAA NCEI), Western Pacific basin. Storms marked LIVE are fetched straight from NOAA NCEI's IBTrACS active-storms feed in your browser, then topped up from the JTWC working best track itself (the ATCF b-deck, openly mirrored by UCAR/RAL, updated several times a day) — so an active typhoon's history runs to the latest fix, and its 50/64 kt radii appear the moment JTWC publishes them (the working best track reports the 34 kt radii first; 50/64 kt usually arrive in post-analysis, which is also why 2025-onward storms show only Level 8 (34 kt) circles for now). Taiwan (CWA) classes use CWA's official 10-minute thresholds (17.2 / 32.7 / 51.0 m/s) applied to JMA's real 10-minute wind analysis for each point (carried in IBTrACS as TOKYO_WIND — the same averaging convention CWA uses, so storms class the way CWA's own record does, e.g. Doksuri 2023 as mostly 中度 rather than the inflated 強烈 a converted 1-minute wind gives); points between JMA's 6-hourly analyses interpolate, and only storms with no 10-minute record at all fall back to 0.88-converted 1-minute winds. CWA's and JMA's own analyses can still differ slightly — both are real agency data. Wind circle radii (Beaufort force 8/10/12 — gale/storm/hurricane-force, JTWC's 34/50/64kt radii, per quadrant) are JTWC (USA agency) reports, which is why coverage starts in 2001 — systematic quadrant reporting didn't exist before then, for any storm in this archive, so it can't be extended back to 1985. Radius shapes interpolate between the four reported quadrant extents; treat them as an approximation, not a precise wind-field boundary. The Dvorak T-number is estimated from each point's wind speed via the standard Dvorak CI-number/wind-speed table — a standard approximation, not an independent satellite reading. ACE, rapid intensification (≥30 kt/24 h), and the season climatology are all computed from this same best-track wind record. The forecast cone is a persistence baseline — it simply projects the storm's current heading and speed forward, with a cone sized to typical average track error; it is the naive benchmark real forecasts are measured against, shown to contrast with the actual track, not a skilful prediction. ENSO tags use real NOAA CPC ASO ONI values.