Mumbai Despite the city keeping its date with the onset of the southwest monsoon on June 11, there is no active monsoon spell expected in the city till at least June 20, officials of the Indian Meteorological Department (IMD) officials and experts said on Monday.
They further added that warmer temperatures, muggier conditions and a few spells of patchy rain in isolated locations are expected to prevail.
The city’s tide-chart for June shows that high-tides up to 4.95 metres are expected between June 14 and June 18 during the afternoons, indicating that rains will give the city a miss during an optimum window for flooding.
“However, this doesn’t mean you won’t see any flooding later in the month. Three to four metre high tides would still occur, and if you get something like 150mm of rain in half a day or so, there will definitely be an impact,” said Akshay Deoras, independent meteorologist and PhD candidate at the University of Reading, UK.
“There has been a sharp decline in rainfall since Sunday. The onset of the monsoon has been weaker than usual this time. Though there is an offshore trough running from south Gujarat to Kerala, its position at the moment is unfavourable for rains in the city,” said KS Hosalikar, head of the IMD’s surface instrument division in Pune.
So far this month, Mumbai has recorded 79.8mm of rain, indicating a deficit of -65.5mm. The normal rainfall for the month, as per IMD’s long-period average, is 505mm. In June last year, the city received a total of 967.7mm of rain, making it the highest rainfall received during the month in six years. 706mm of rain was recorded in the first 12 days of the month alone.
“You need a proper wind pattern, moisture, a lot of atmospheric instability and daytime heating for these thunderstorms to occur. The monsoon has been slowly progressing along the coast of Maharashtra, so the wind pattern and atmospheric state over Mumbai is changing, suppressing thunderstorms. The only source of rain would be localised light rain activities from local clouds. Due to weak moisture incursion, there isn’t sufficient moisture in the atmosphere to sustain day-long proper rainfall events in Mumbai-MMR,” Deoras added.