Over the last 48 hours, incessant rain (10 inches in places), heavy snow and a delay in the withdrawal of westerly winds have extended India’s Monsoon season.
Rainfall in Northern India normally occurs when localised depressions, caused by summer heat, attract moisture laden winds from the Bay of Bengal.
But the rain experienced by the region over the last 48 hours is a result of moisture from both the Bay of Bengal to the east and the Arabian Sea to the west — strong westerly winds are pulling moisture from Cyclone Daye upwards resulting in a “double dose” of rain for the North.
Although Cyclone Daye made landfall in the far Southwest on Friday, at Gopalpur in Odisha, the resulting winds cover a large part of India and deliver widespread rainfall.
“The large low pressure area caused by Cyclone Daye got ‘hooked’ with the westerly winds coming from the Arabian sea, taking the moisture upwards towards north,” said India Meteorological Department (IMD) director general KJ Ramesh.
1) CYCLONE: Cyclone Daye off the coast of Odisha extended a deep depression (high moisture content) over Central India.
2) DEPRESSION: The cyclonic depression brought heavy rainfall and flooding to the southern Indian states of Andhra, Telangana and Karnataka.
3) WESTERLY WINDS: The westerly winds carry moisture from the Arabian Sea northwards causing record rains in western and northern India.
Rainfall In Northern India
The heavy rainfall has damaged paddy crops in large parts of Punjab and Haryana.
According to local farmers, vast areas of paddy, which is at the maturing stage, have been flattened.
The conditions also led to a 5C dip in temperature which resulted in two feet of snow falling in the upper reaches of Himachal Pradesh and Jammu & Kashmir — highly unusual for September.
As a result of the snow, the apple, pea and potato crops in Lahaul have suffered “massive and unprecedented damage”.
SOLAR VARIABILITY AND WEATHER
Research shows blocking persistence increases when solar activity is low, causing weather patterns to become locked in place at high and intermediate latitudes for prolonged periods of time.
During a solar minimum, the jet stream’s usual Zonal Flow (a west–east direction) reverts to more of a Meridional Flow (a north-south direction) — this is exaggerated further during a GSM, and explains why regions become unseasonably hot or cold and others unusually dry or rainy, with the extremes lasting for an extended period of time.
It is estimated that flooding and drought regimes will become far more frequent as we descend into this next Grand Solar Minimum.
And the evidence is mounting: