Friday, January 01, 2010
Happy New Year
India Weather :2009
2009 will be remembered, weather wise, for the bad Monsoon. Deficit had been assessed at 23 % for the southwest Monsoon, making it the second worst Monsoon in the last 37 years.
The deficit climbed up close to the 23.9 % recorded in recent memory (1972). The next worst is the 24.9 % recorded way back in 1918. And 1899 was -26%. Lowest ever was 1877 at -29%.
Even then, weak rains in the peninsula continued well after the official Monsoon season into October and November. So much so, that it made it the 2nd. wettest November in many cities of Maharashtra (due to Phyan).
The warming up for the Monsoon (summer), had started well in the year, with a heat wave in mid-April, gearing up the atmosphere for a "healthy and early Monsoon". But Cyclone "Bijli", and the subsequent rains in the Central Peninsula, disrupted the normal summer pattern, and the sub-continent saw no "major" heat wave in rest April and May. Resultantly, the Monsoon too arrived late.
It was a late December arrival of Winter for the Indian Sub-continent. The temperatures dropped, somewhat to below normal levels, only in the last week. End December saw the season's lows at: Leh/Kargil -19c, Srinagar -5c, Delhi's low at 5c, Amritsar -0.6c.
But, effectively, we have not seen the cold waves, with nights going more than 3c below normal. In fact, the cold conditions have not penetrated southwards below Punjab/Haryana.
For the Central/Western regions, not much, except some pockets of "good" cooling in Maharashtra,with seasonal lows of: Pune/Nasik at 8c, Ahmednagar at 6c.
South has still to get the feel of its winter.
Western Disturbances, are low presuure systems, or cold fronts, that form and originate somewhere near the Caspian Sea region, or the Mediterranean Sea. The system then moves eastwards precipitating along its route, along the central Asia- middle east route into the sub-continent.
On an average, Northern regions can get at least 1/2 really effective W.D's in November, and 2/3 in December. But this year, as yet, a real strong W.D.has remained absent, and a couple of weak and feeble W.D's have moved along the upper regions of the Northern sub-continent. They being mild, have been unable to actually bring any precipitation to the plains of the region.
Hence our regions are still to get the effects of a strong W.D. Our winter rains, for the Northern regions have been deficient, as seen in the rainfall map.
Hopefully,lets not see a dry winter, like the summer monsoon.
For the south, the North-East Monsoon has been fairly on the average level, maybe a bit excess in pockets.
But, though prolonged beyond date it has again lacked the heavy precipitation and downpours in the coastal regions. The Nilgiri Mountains did have an initial very heavy burst of torrential downpours, with 30-50 cms in a day, with a record 80 cms. Though Tamil Nadu was normal at +12%, Nilgiri district had surplus of more than 250 %.
North Interior Karnataka was surplus at +110%, while the rest of the state's above average at +50% was comforting.
Kerala was just about normal at +6%, and A.P. was along the normal lines at +15%.