Comments by Praful Rao
We have been witnessing an extraordinary rainfall pattern over the last few weeks in this region.
In Kalimpong, we were terribly deficient in rain from 01-09Sep2012 but between 10-17Sep2012 due to the monsoon trough shifting close to us and an upper air cyclonic circulation over Jharkhand, we received around 84% (343mm) of our monthly rainfall for Sep (410mm) in just 7 days and by 20Sep we crossed out monthly average.
What is worrisome is that this intense rainfall comes at the end of the monsoon season when the earth is totally saturated with water - creating an ideal recipe for landslides.
Sikkim receives much more rain than Kalimpong and I do know that this month they have gone well past the monthly average there.
Placed above is the IR image of 22Sep2012 of 1600hrs (ie of yesterday when the landslide/ flashflood occurred) which shows dense clouding over Sikkim.