Enhanced pre-monsoon thunderstorm activity during the last seven days has helped improve rainfall deficit situation over Tamil Nadu by almost 20 per cent to -39 per cent till yesterday, Wednesday (April 29). But Saurashtra and Kutch in West India saw the deficit worsen from -29 per cent to -34 per cent and so too the North-Eastern States, rainfall statistics put out by India Meteorological Department (IMD) reveal.
Tamil Nadu may have another couple of days for even more thundershowers before the low-pressure area brewing farther away in the South Andaman Sea to the extreme South-East begins to intervene by bringing a barrage of predominant dry north-westerly winds. These winds could also raise the day temperatures over the state as the low goes on to intensify.
All-India situation comfortable
In fact, the above mentioned meteorological subdivisions are the only few which are in deficit, while the rest of India has received normal to above normal rainfall during the pre-monsoon season that began on March 1 and shall last until May-end. The season has so far delivered above normal rainfall of 26 per cent till yesterday, ensuring satisfactory storage conditions across the country and adequate supply for farmers.
The low-pressure area in the South Andaman Sea, expected to form anytime during the next two days, is forecast to intensify and maintain a track towards Myanmar and adjoining South Bangladesh, the IMD said. This, as mentioned already, will mean a brief recess in thundershower activity over Peninsular India. But the building heat may spawn even more thunderstorms as the influence of the low-pressure area/depression in the Bay wears off.
Trough over Peninsular India
A prevailing trough/wind discontinuity (where opposing winds from the seas meet) across Peninsular India will continue to trigger scattered to fairly widespread rain or thundershowers over Kerala and Coastal Karnataka during next two days while it would be scattered rain/thundershowers over Konkan, Goa and Interior Karnataka until tomorrow (Friday). Isolated thunderstorms, lightning, gusty winds (30-40 km/hr) are also likely over these regions during this period.
The IMD expects it intensify, and concentrate into a depression by May 2-3 before intensifying another round (to a deep depression, a step from away from being called a cyclone). It may move North-North-West (into Central Bay) during May 1-3 and subsequently to the North-North-East towards Myanmar–Bangladesh coasts. It may not affect any part of the East Coat of India, but the Odisha and West Bengal coasts may need to stay alert.
High winds forecast
Squally winds speed reaching 40-50 km/hr gusting to 60 km/hr (almost depression strength) are forecast the South Andaman Sea, the Nicobar Islands and the adjoining South-East Bay tomorrow (May 1, Friday)of Bengal. Wind speeds may reach 45-55 km/hr gusting to 65 km/hr (cyclonic gusts) over the same regions on Saturday and 50-60 km/ht gusting to 70 km/hr (a deep depression) over the South-East Bay and adjoining South Andaman Sea on Sunday and Monday.