What the archive can measure

Every forecast in this archive is paired with the track that followed it, and every season sits beside seventy-six seasons of ocean records. That makes some questions answerable with arithmetic instead of anecdote. These pages hold the answers, every number computed from the data at build time.

• How much more warning does a hurricane forecast buy now?Measured from every official forecast in this archive: two thirds of 24-hour forecasts now verify within 36 nautical miles, against 78 in the Iniki era. Today's 64-hour forecast is as accurate as a one-day forecast was then.
• Does El Niño really bring Hawaii more hurricanes?76 seasons of NOAA data say: mostly. El Niño seasons average 1.7 storms within 500 km of the islands, La Niña seasons 0.8 — but the biggest disaster on record arrived in a neutral September.