Saturday, September 06, 2008

A fairly active W.D. has moved across northern subcontinent, and precipitated good rains in the region and snow on the mountains. In Pakistan, heavy rains in the north-east has occured, but the rains may be restricted to that region, as the W.D. moves away. Local fall in temperatures in the far north can be expected.
A steady drizzle brought down the temperature in Srinagar by several degrees, giving the residents the first feel of impending winter. an overall drop in day temperatures today, due to the W.D. is seen in the map from University of Cologne.
The normal temperature today was whopping 7°C less than the normal. The resort of Gulmarg, and other higher reaches had the first snowfall of this season. In H.P., heavy hailstorms lashed the hilly region.

This system has distanced itself from the southerly monsoon currents, but southwards, the monsoon south-westerlies are making a "final attempt" to re-group. A weak orderly south-west wind has re-formed along the central and western areas of India, as seen in the IMD 925hpa map. Also, due to regrouping, overnite changes in model predictions are made.

-The IMD forecasts a low in the bay by the 7th. and some rain as a result along the regions west of the low crossing the east coast. On the crossing of the predicted low inland, the west coast, and ghat stations of M'shwar/Lonavala can get sudden heavy precipitation, around Tuesday/Wednessday (9th./10th.).

-This is enforced by COLA, which predicts, (most probably the same low), to cross into the Arabian Sea. Resultantly, a low vortex is forecasted off the coast of Karnatak/Maharashtra around the 9th. Result: Heavy rains along the coast and ghats on these days.

-Meanwhile, the ECMRWF also forecasts a depression crossing the A.P. coast around the 15th. If true to forecast, much more rain can be expected by the 15th./16th. in the states directly in the path of the depresiion. ( could be north westwards from the A.P. coast, as indicated by the forecast model).

Again, if true to forecast, my estimate of the monsoon widhrawal date should be extended ( stands much to the benefit of the entire peninsula region).

If the above systems do not materialise, or , if the recent regrouping is weak and temporary (we hope not), the ensuing northerly dipping trough (W.D.), is going to push the monsoon axis southwards really fast.

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