MAY 21, 2017, SUNDAY
As the southwest monsoon marshals its forces for an Indian entry into Kerala, doubts remain as to what will be the arrival like. Will it be steady, undeterred by a tropical cyclone gulping away some of its moisture and stamina? Or will an Arabian Sea tropical cyclone snatch away some its momentum as it veers off tangentially to Oman?
A Bay of Bengal/Arabian Sea storm is beneficial for monsoon rains in India if the system makes landfall into the indian coast. It acts as a locomotive which pulls along the rains into the country. A cyclone going to Myanmar or Oman is not conducive for Indian monsoon. They suck away considerable amount of the monsoon's energy and from an Indian perspective counterproductive.
Meanwhile the numerical weather prediction (NWP) models are taking us on a wild goose chase. Not only are they not agreeing with one another but contradicting themselves in successive data output.
The GFS was indicating a Bay of Bengal storm yesterday, is predicting an Arabian Sea cyclone today. According to it the storm will start off as a low near the Kerala coast on May 30/31 then intensify into something awful and hit Oman by June 6.
Meanwhile even the stolid, European ECMWF with their much vaunted supercomputers too seem to be confused. Earlier it was predicting an Arabian Sea cyclone going to southern Oman/Yemen. Now it foretells a depression in the Bay of Bengal on May 31 near the Myanmar coast.
Presently the Indian Ocean is in a state of tremendous flux as the approaching rainy system is creating massive turbulence. The utter anarchy of nature is such that even the biggest man made supercomputers are unable to discern any pattern. Simply put the supercomputers cannot make head or tail out of the prevailing situation in the ocean.
That is why we are seeing ever changing contradictory forecasts by the NWP.
The GEFS (Global Ensemble Forecast System) believes monsoon will hit Mumbai on June 4, 2017
