Strong thunderstorm activities are expected over northwest India today (Tuesday, April 4, 2023), according to IMD (Indian Meteorological Department) scientist Soma Sen. Hail and strong gusty winds are expected over Punjab, north Rajasthan, Himachal Pradesh, Uttarakhand, and western parts of Haryana, Sen told news agency ANI. The intensity of the thunderstorm activities will be greater in these states compared to other regions of India.
What are the other states in which the thunderstorm activities are likely to occur?
Some thunderstorm activities are likely to occur over western Uttar Pradesh and Jammu and Kashmir, Sen said. Due to these reasons, the IMD has issued an orange alert for the states that are likely to experience thunderstorm activities today.
Why are strong thunderstorm activities likely over northwest India?
Sen explained that the thunderstorm activities over northwest India can be attributed to the interaction of an 'intense western disturbance' lying over east Iran, and a 'low-level' circulation over west Rajasthan. The western disturbance is lying over east Iran as a cyclonic circulation, Sen said.
Since the western disturbance will gradually move eastwards during the course of the day, it is likely to interact with the circulation over west Rajasthan.
Sen said that there will be a region of convergence, which is a zone in the atmosphere where two prevailing flows meet and interact, resulting in distinctive weather conditions. The conditions will be intensified due to the interaction of the cyclonic circulation and the circulation over Rajasthan.
Western disturbance likely to become weaker tomorrow onwards
The IMD scientist explained that from April 5, the western disturbance is likely to become weaker. Therefore, the effect of the western disturbance on the weather of North India will decrease.
Gradually, the western disturbance will move eastwards.
Are thunderstorm activities expected over Delhi?
Sen said that thunderstorm activities are expected over Delhi today. However, the intensity of the thunderstorm activities that are likely to occur over the national capital cannot be specified. While an orange alert has been issued for different states of northwest India, an IMD alert on the 'Now Cast' scale will be issued for Delhi.
What is meant by a ‘Now Cast’ warning and an ‘orange’ alert?
When a Now Cast warning is issued, it is valid for the next six hours from the time of issuance, and is updated every 15 minutes as and when triggered by the observing system.
An 'orange' warning represents 'alert', and calls for administrators to 'be prepared'.
In the case of isolated heavy to very heavy rainfall, which occurs consecutively for three days, an orange alert is used for the first and second days.