The morning hours in Mumbai are witnessing cool northeasterly winds but as the day progresses, southeasterly winds are taking over. In such wind conditions, inversion (a weather event in which the cold air near the surface does not mix easily with the warmer air above and gets trapped) is taking place so, instead of decrease in temperature with height, temperatures are actually increasing.
According to Mahesh Palawat, Chief Synoptician at Skymet Weather, an anti-cyclonic circulation over Mumbai and nearby areas at 1500m above the surface is not letting the warmer winds come down to the surface thus creating a constant layer of warm winds that is holding up the heat radiation from releasing.
Wind condition changes as the day progresses, the cool morning winds start heating up and increase the temperatures. Due to inversion and pollution, the temperatures are up by 3 to 4 degree above normal. The minimum temperatures are into early 20s while the maximum temperatures are approaching mid-thirties.
Due to the these conditions coupled with congested roads and constant constructions, pollution levels have increased three-fold over the standard acceptable limits last week, leaving the weather in Mumbai stifling warmer.
According to the Mumbai Pollution Control Board, pollution levels-particularly nitrogen oxide (NO2) and suspended particulate matter (SPM)-have been exceptionally high in the past few days. While the pollution levels in January were more than double the accepted limits, they further worsened in February.
For instance SPM levels rose to as high as 342 micrograms per cubic meter on February 1st. The levels were 335 micrograms per cubic meter on February 6. The NO2 levels were not as scary as the SPM levels, but they were still high, take into consideration 178 micrograms per cubic meter on February 7th.
Photograph by wallygrom