Wind Speed

Tools

By Megan Valentine

Story Published: Jul 18, 2007 at 12:48 PM EDT

Story Updated: Jul 18, 2007 at 12:48 PM EDT

A High Wind Advisory is issued when sustained winds of 30-40 mph or non-convective wind gusts of 45-58 mph are occuring or imminent.
A High Wind Warning forecasts sustained winds of 40+ mph for at least one hour, or non-convective wind gusts of 58+ mph.

How Fast is the Wind Blowing? Since most of us don't have an anemometer in our yard, the Beaufort scale is a good guide:

Wind Speed mph	Description	Indications
0-1	Calm	Smoke rises vertically. Water is like a mirror.
1-3	Light air	Direction of wind shown by smoke drift, but not by wind vanes. Ripples with the appearance of scales are formed.
4-7	Light breeze	Wind felt on face; leaves rustle; ordinary vanes moved by wind. Small wavelets, still short, but more pronounced.
8-12	Gentle breeze	Leaves and small twigs in constant motion; wind extends light flag. Large wavelets.
13-18	Moderate breeze	Raises dust and loose paper; small branches are moved. Small waves, becoming larger.
19-24	Fresh breeze	Small trees in leaf begin to sway; crested wavelets form on inland waters.
25-31	Strong breeze	Large branches in motion; whistling heard in wires; umbrellas used with difficulty.
32-38	Near gale	Whole trees in motion; inconvenience felt when walking against the wind.
39-46	Gale	Breaks twigs off trees; generally impedes progress.
47-54	Severe gale	Slight structural damage occurs.
55-63	Storm	Seldom experienced inland; trees uprooted; considerable structural damage occurs.
64-72	Violent storm	Very rarely experienced; accompanied by widespread damage.
73-83	Hurricane	Hurricane
100-300	Killer Tornado	See Tornadoes