- January 11, 2022
- Posted by: admin1
- Category: DPN Topics
Subject – Geography
Context – Unseasonal rains, hailstorms damage Maharashtra rabi crops
- A hailstorm is a thunderstorm that produces ice as precipitation. Hailstorms can cause serious damage to crops and property.
- In India, hailstorms mostly affect the northeast and western Himalayas, with the maximum strikes in March and April.
- Unlike other forms of water ice precipitation, such as graupel (which is made of rime ice), ice pellets (which are smaller and translucent), and snow (which consists of tiny, delicately-crystalline flakes or needles), hailstones usually measure between 5 mm (0.2 in) and 15 cm (6 in) in diameter.
- Hail is possible within most thunderstorms (as it is produced by cumulonimbus), as well as within 2 nmi (3.7 km) of the parent storm.
- Hail formation requires environments of strong, upward motion of air with the parent thunderstorm (similar to tornadoes) and lowered heights of the freezing level.
- In the mid-latitudes, hail forms near the interiors of continents, while, in the tropics, it tends to be confined to high elevations.
- Hailstones generally fall at higher speeds as they grow in size, though complicating factors such as melting, friction with air, wind, and interaction with rain and other hailstones can slow their descent through Earth’s atmosphere.
Favourable conditions for a hailstorm
Hail forms in the strong updraft region of a thunderstorm. Atmospheric conditions favourable for the formation hail bearing thunderstorm are:
- High degree of instability,
- High moisture content,
- Low freezing level,
- High vertical wind shear.