THIRUVANANTHAPURAM: Exhausted by the intense heat and prolonged dry spell, Keralites are heaving a collective sigh of relief as summer showers lash the state. Adding to the cheers, the India Meteorological Department (IMD) has forecast more rain in the coming days.
According to the IMD, heavy rain is likely from Thursday through May 2. Several districts, including Pathanamthitta, Wayanad, Ernakulam and Alappuzha, have already recorded significant rainfall these past few days.
Yellow alerts indicating the possibility of heavy rain at isolated places have been issued for Kannur and Kasaragod on Thursday; Pathanamthitta, Idukki and Wayanad on Friday, and Kottayam, Ernakulam and Alappuzha on Saturday.
“The rainfall marks a transition from the prolonged heat conditions that prevailed across the state,” IMD director Neetha K Gopal told TNIE. “Tuesday marked the end of the heat alert as well as high UV index alert. Now, the state is under alerts for thunderstorms and lightning. From Thursday, we have issued warnings for heavy rainfall,” she said. Neetha noted that the current pattern was driven by fast-moving thunderstorm systems that develop over the hills and move westwards towards the sea.
“These are east-to-west moving systems. Though short-lived, usually lasting about half an hour in a place, these can be intense, bringing strong winds and lightning in localised areas,” she said.
Neetha said storms have strong vertical development due to the preceding heat conditions. “After such a prolonged heat episode, these clouds grow vertically up to 10-12 km in the atmosphere, leading to intense but brief spells of rain,” she said. The IMD expects this pattern of afternoon thunderstorms to continue as atmospheric conditions remain favourable. “We are now seeing increased influence of westerly winds from the Arabian Sea along with a deepening north-south trough. These are favourable for continued rainfall,” she said.
Though the rain brought relief, hot and humid conditions persisted in parts of the state on Tuesday. The IMD cautioned that even in the absence of heatwave alerts, prolonged exposure to direct sunlight, especially during morning hours,, should be avoided.
“Mornings will continue to be sunny, and UV exposure can still be strong when cloud cover is less. People should not let their guard down just because rain has started,” the IMD director said.
The IMD has also indicated a likelihood of normal to above-normal rainfall for May. However, the seasonal monsoon outlook still points to a “below normal” category for the June-September period in India.
“The impact of El Nino, expected to develop around June-July, is typically seen in Kerala more during the latter half of monsoon season. The first half may see near-normal rainfall,” Neetha said.
She said a revised monsoon forecast is expected by May-end, which will provide a clearer picture of rainfall trends for the second half of the monsoon season.
Warning issued
Yellow alert (7-11 cm rainfall in 24 hours)
Kannur & Kasaragod (Thursday).
Pathanamthitta, Idukki & Wayanad (Friday)
Kottayam, Ernakulam & Alappuzha (Saturday)
Weather forecast: Thunderstorms accompanied by lightning and gusty wind speed reaching 40-50 kmph are very likely to occur at one or two places over Kerala from April 29 to May 2.