Post-monsoon rains drench Pb, Hry, HP

Western disturbances have brought widespread rain to northwest India, leading to a significant post-monsoon precipitation surplus during the first week of October.

In Himachal Pradesh, rainfall this month has reached a surplus of 625 per cent, with the state receiving 25.7 mm of rain from October 1 to 7 against a long period average (LPA) of 0.9 mm.

During the past 24 hours, Solan was the wettest district with 38.8 mm, followed by Lahaul and Spiti with 36.3 mm and Kullu with 24.9 mm, according to data compiled by the India Meteorological Department (IMD). The statewide mean rainfall was 2,753 per cent above the LPA.

Several upper reaches also experienced snowfall in the past two days, with light rain and possible snow at higher reaches expected on October 8 and 9, the IMD said.

Punjab has recorded a 727 per cent rainfall surplus so far this month, receiving 20.7 mm of rain against the LPA of 2.5 mm. Over the past 24 hours, Pathankot received the highest rainfall at 24.3 mm, followed by Mohali with 18.1 mm and Gurdaspur with 12.2 mm, while Fazilka remained dry.

In Haryana, where October rains show a 529 per cent surplus, all districts experienced light to moderate rain with thunderstorms and gusty winds. Mahendragarh was the wettest with 33.4 mm, followed by Yamunanagar with 30.6 mm and Palwal with 28 mm. While widespread rain continued on October 7, the weather in Punjab and Haryana is expected to turn dry from October 8 onwards. Maximum temperatures across these states remained markedly below normal, while minimum temperatures were normal.

This unseasonal wet spell has implications for agriculture and for inflows into major reservoirs, where water levels are being maintained below the upper limit to provide a cushion for potential surges from heavy rainfall in the catchment areas.

Heavy unseasonal rains over north-west India during October were last experienced in 2023, when freak weather events in Himachal Pradesh led to cloudbursts in the dams' catchment area, requiring flood gates to be opened.

This year, the Pong Dam on the Beas saw unprecedented inflows during August-September, with water levels remaining up to 5 ft above the upper limit for weeks, while the water level at Bhakra Dam remained below its upper limit.

Pong is located in Kangra district, close to the border with Punjab. The dam’s catchment area lies across Kullu, Mandi and Kangra districts. According to IMD data, rainfall in October has remained 721 per cent surplus in Kullu, 492 per cent in Mandi and 496 per cent in Kangra.

The Sutlej River, which feeds the Bhakra reservoir, flows through Kinnaur, Shimla, Mandi and Bilaspur, and these districts have recorded excess October rains of 686 per cent, 514 per cent and 992 per cent, respectively. Similarly, the Ravi, which feeds the Thein Dam in Punjab, flows through Kangra and Chamba in Himachal and Pathankot, Gurdaspur and Amritsar in Punjab, all of which have experienced surplus rains this month.