All phenomena
Small, intense downdrafts that spread damaging winds outward when they reach the ground.
16-Bit Take (analogy): A downward wind burst that spreads out like a shockwave animation.
The science
Falling precipitation and evaporative cooling can accelerate a downdraft. On reaching the surface, it fans outward as straight-line wind.
How to spot it
A rain shaft or spreading dust may be visible, but appearances are unreliable. Use official thunderstorm warnings.
Where
Beneath showers and thunderstorms in suitable environments.
Best season
During the local convective-weather season, though not limited to summer.
- ▸The affected outflow area is less than about 2.5 miles across.
- ▸Wet microbursts bring substantial rain; dry ones may bring little to the surface.
- ▸Rapid changes in wind are especially dangerous to aircraft near the ground.
Rarity and hazard ratings are informal editorial guides, not measured occurrence rates or official warnings. Local conditions determine actual risk.
Sources
Related guides
- Haboob
An advancing wall of dust raised by thunderstorm outflow winds.
- SQUALL LINES
Storm formation flight - squadron of thunderstorms marching in military precision
- MESOSCALE CONVECTIVE COMPLEXES
Thunderstorm metropolis - sprawling city of storms dominating the night sky