Sunday, April 12, 2009

Monsoon Watch-3

Cooling was limited and short-lived over northern/central India on Wednesday and Thursday. Already, as of Saturday and Sunday, it has heated markedly over Maharashtra, both inland and at coastal. At Mumbai, strong sunshine made the mercury touch nearly 40 degrees C. The high was 39.7, and 39 on Friday and Sunday.

Well, in the interior,Akola registered 43c on Sunday. Surat, heated to 42c .Normal heat in Surat would be about 37 c.


It is going to get hotter over the Subcontinent, as a whole, and it will stay that way through at least the middle of next week. Owing to the strong winds from the north/west over the region, as seen in the streamline, and a high pressure aloft at 500hpa, holding on over the Subcontinent through the coming week. This will create a heat wave and,. I estimatefor 42- 45c range heat away from the coast, that is inland over north-west, central and Maharashtra regions.


All this augments well for the pre monsoon developments, estimated to start by the end of next week. That is the starting of the seasonal low. At present the pressure in the required region, Rajashtan and adjoining regions is at 1006 mb.


The streamline map indicates that the southern hemisphere winds are taking a little longer to get organised for the "monsoon assault".


Again a reminder, One heat wave does not prove or disprove climate change.
"Often the public blurs the distinction between the two," says the Environment Canada spokeman."But they're very different and at times it's frustrating."
When meterologists use the term "climate," they're referring to long-term averages of weather patterns, measured not in years but decades.
What's less clear is the correlation between climate change and extreme weather patterns.

My attempt illustrates the difference is to show that, no, you cannot "term" a record-breaking cold snap last winter or heat wave this summer into a climate change-related discussion. Climate models are measured in larger scales than one day, or even one season.

A low pressure area has started building up around Sri Lanka. This will keep almost most of southern India away from the the worst of the heat, at least for the next two to three days. And there will be showers and thunderstorms in Karnataka, with isolated spots getting upto 5-7cms of rain in T.N.

Also, it would be the perfect pre monsoon condition, if as forecasted, the Bay of Bengal could give rise to depression or cyclone, within the next several days. I would be cautious in forecasting a cyclone as yet. But , vis-a-vis the weather, one can never say !












No comments: