Aviation weather in North America

Continental extremes in one airspace: summer squall lines across the Midwest, freezing rain and de-icing queues from November, and Pacific coastal fog that closes approaches on clear-looking mornings.

At a glance

Main hazards Thunderstorms, Airframe icing, Snow and contamination, Turbulence, Fog
Most demanding season November – March
Thunderstorm season May – August
Representative airports KJFK · KORD · KDEN · KATL · CYYZ
Official sources NOAA Aviation Weather Center · NAV CANADA Flight Planning

The services linked above are the authoritative source for this region. This page explains what their reports contain; it is not a substitute for an official briefing.

What these hazards mean

Thunderstorms Cumulonimbus cells carrying severe turbulence, hail, lightning and downdraughts; avoided laterally, never flown through.
Airframe icing Supercooled water freezing on the wing, changing its shape and adding weight — worst between 0 °C and −20 °C in visible moisture.
Snow and contamination Snow, slush and ice on the runway cut braking action and change the accelerate–stop distance; de-icing adds holdover-time arithmetic.
Turbulence Clear-air, mechanical or convective. The clear-air kind gives no visual warning and is why the seatbelt sign stays on in cruise.
Fog Radiation fog forms on clear, calm nights and burns off late; sea fog can sit for days. It closes airports that were forecast open.

METAR decoder

Paste a raw observation and read it in plain language. It runs in your browser — the report never leaves your device, and nothing is stored.

Works with ICAO reports and with the North American SM / inHg variant.

Related guides

Rime ice building along the leading edge of a wing in cold cloud

Aircraft Icing Explained: Where It Forms, and Why It Is So Serious

Ice changes the shape of a wing, and a wing is only a shape. Here are the three types, the temperature band that produces them, and what the reports tell you in advance.

Weather hazards in flight 9 min read

A mature cumulonimbus with a spreading anvil, seen from cruise level

Thunderstorms and Convective Weather: Why Aircraft Go Around Them

A cumulonimbus contains every serious weather hazard at once. Here is what is inside one, how far aircraft stay away, and why the avoidance is lateral.

Weather hazards in flight 9 min read

De-icing fluid arcing over a wing in the dark before an early winter departure

Winter Operations: De-icing, Holdover Times and Contaminated Runways

Why winter departures collapse into queues, what a holdover time really is, and how a runway condition code changes the numbers a crew has to meet.

Regional aviation weather 9 min read

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Last updated 2026-08-09 by aviationwheater.siten.co · About us

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