Boston Logan does not usually lose hundreds of flights to a September weekend. This one it did. A powerful nor'easter parked off the New England coast from Friday 25 September, bringing heavy rain, coastal flooding and, crucially for aviation, wind. Lots of it.

By Saturday 26 September, Logan had logged 253 cancellations, according to FlightAware figures reported by AeroTime. The small island airlines took the hardest hit. Cape Air cancelled every flight in its North region, and the airports on Nantucket and Martha's Vineyard were left almost silent. The ripple travelled a long way: KTLA reported disruption as far away as Los Angeles.

Why Wind, Not Rain, Grounds the Fleet

Airliners land in rain all the time. What stops them is wind, and above all wind blowing across the runway in gusts. Every aircraft type has a maximum demonstrated crosswind, and airlines set their own limits, often lower on a wet runway where braking is poorer. When the gusts climb past those numbers, the choice is simple: hold, divert or cancel.

Ahead of the storm, the National Weather Service forecast gusts of 40 to 55 mph in Boston and 50 to 65 mph on Cape Cod. Pilot and author Patrick Smith told CBS Boston that flights were likely to be grounded once winds passed around 40 mph. Wind direction matters just as much as strength: it decides which runways an airport can use, and a busy airport forced onto fewer runways has to accept fewer arrivals per hour.

That explains why Cape Air carried the biggest share of the cancellations. Its Cessna 402s and Tecnam P2012 Travellers are light twin-engine commuter aircraft that link Boston with Nantucket, Martha's Vineyard, Provincetown and Cape Cod. Light aircraft are far more exposed to gusts than a 200-tonne widebody, and the island airports sit right in the teeth of the coastal wind. AeroTime counted 115 Cape Air cancellations at Logan alone on Saturday.

Waivers, Refunds and the Weekend Ahead

The big carriers moved early. JetBlue, United and American waived change fees and fare differences for Boston travel over the weekend, and Delta allowed free changes into the following week, according to CBS Boston. Cape Air let passengers rebook through 2 October without penalty. AeroTime reported that the waivers cover travel between 25 and 29 September.

One rule is worth knowing whatever the weather. Under US Department of Transportation rules, a passenger whose flight is cancelled and who decides not to travel is entitled to a refund rather than a voucher, even when the cause is a storm. Rebooking is the airline's offer; the money back is the passenger's right.

Nor'easters are a familiar part of New England flying, most often in the colder months, and airlines plan for them the way they plan for snow. The early-season timing made this one awkward, landing on a busy autumn weekend. Once the wind drops, the recovery depends on getting aircraft and crews back into position, which is why delays tend to outlast the storm itself.

KTLA reports on how the nor'easter's flight disruption spread well beyond the Northeast, reaching Los Angeles. Video: KTLA 5

Sources: AeroTime, CBS Boston, KTLA, National Weather Service, US Department of Transportation