Delhi to witness 5th 'cold day' of January today: IMD
Delhi is bracing for yet another "cold day" on Saturday, with the India Meteorological Department (IMD) issuing an orange alert amid dense fog. This will be Delhi's fifth "cold day" this month, as strong jet stream winds in the upper atmosphere turn North India's plains colder than usual. The IMD also predicted the maximum temperature would stay below 20 degrees Celsius over the next six days in Delhi, while the minimum temperature will likely hover around 7 to 9 degrees.
Why does this story matter?
Much of North India has been blanketed by thick fog amid a cold wave since last month. This resulted in severe disruption of flight operations at the Delhi airport. Though fog has decreased in recent days, the IMD has predicted dense to very dense fog over North India until Saturday. The cold wave is, however, expected to continue over parts of the Indo-Gangetic Plain.
IMD issues orange alert for Delhi
Amid the indication of a cold day in some areas and dense fog, the IMD issued an orange alert for Delhi on Saturday. At the Safdarjung weather station, the base observatory in Delhi, the maximum temperature is predicted to be around 15 degrees Celsius, compared to the normal 19.6 degrees Celsius for this time of year. On Friday, the observatory recorded a temperature of 14.2 degrees Celsius—5 degrees below normal.
Fog delays 11 trains; visibility improved at Delhi airport
With dense fog in the early hours on Saturday, 11 trains reaching Delhi from around the country were running late due to poor visibility. However, fliers have received some respite as the visibility at Delhi's Indira Gandhi International Airport considerably improved. The fog there was less dense than on previous days, and the visibility was over 1,000 meters. Moreover, morning temperatures in Delhi-NCR were slightly higher than usual due to cloud cover.
Jet stream winds affecting North India's temperatures
IMD officials attributed cold wave conditions in North India to jet stream winds of approximately 130 to 140 knots (240-260km/h) at 12.6km above mean sea level. RK Jenamani, a scientist at the IMD, stated the speed of the jet stream winds had decreased on Friday from around 250-320km/h earlier this week. The IMD said these westerly winds in the upper level of the atmosphere were expected to persist with similar intensity over the next two to three days.
North India sees temperature drop of up to 8 degrees
Maximum temperatures have plummeted by 5-8 degrees Celsius in North India since December 29, 2023, leading to a lengthy cold spell. There was a slight relief on January 7-8, thanks to a passing western disturbance. However, it was short-lived, as chilly weather returned on January 9. Meanwhile, the IMD predicted that minimum temperatures would decrease by 2-3 degrees in several regions of East India during the next three days, with no major change thereafter.
Know about cold day, severe cold day
A "cold day" occurs when a place's minimum temperature is less than 10 degrees Celsius for two consecutive days and the maximum temperature (or day temperature) falls by 4.5 to 6.4 degrees Celsius below average. On the other hand, a "severe cold day" occurs when, in addition to a minimum temperature of less than 10 degrees Celsius, a region's maximum temperature falls more than 6.5 degrees below average.
