Heat Lightning

Heat lightning is a misnomer for the faint flashes of lightning on the horizon or other clouds from distant thunderstorms that do not have accompanying sounds of thunder. Heat lightning was named because it often occurs on hot summer nights, and to distinguish it from lightning with accompanying thunder. Heat lightning can be an early warning sign that thunderstorms are approaching. In Florida, heat lightning is often seen out over the water at night, the remnants of storms that formed during the day along a sea breeze front coming in from the opposite coast.
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Noun
1. bright flashes of light near the horizon without thunder (especially on hot evenings); usually attributed to distant lightning that is reflected by clouds
(hypernym) lightning

Eng: heat lightning
Urdu: حَر بِجلی ۔ بے کڑک بِجلی کی چَمَک ۔ جو گرمیوں میں شام کے وقت اُفق پَر نظر آتی ہے ۔