THE FALSE STORM- OUTFLOW BOUNDARY OF A MESOSCALE SYSTEM
CLIMATE CHANGE
For people at Kolkata It was a nice slightly cloudy night but still with the moon shining up in the sky and some stars visible but suddenly around 10:30 pm on 10 th of March 2023 cool breeze started blowing and within few seconds it started gaining intensity and soon the windows opened with curious people trying to understand where did this storm came from. Some Neighbours already shouted that “rain is coming” but within 5 to 6 minutes span everything went stand still again. Sky still clear with stars visible and not a single drop of rain. So what was this mystery storm ?
Before fully understanding the science behind what happened it is important to understand what is a mesoscale system ? The meterorolgists and Scientists all over the world still debates often about what storm shall be placed under the category of a mesoscale system. In simple words to explain a mesoscale system is a collection of more than one individual thunderstorm or cloud mass to form a large scale thunderstorm larger than a single thunderstorm but smaller than a cyclone. Such a mesoscale system can often wreck havoc in a city where it passes from. These storms can have violent winds and can have huge amount of thunderstorm developing inside with rapid intensity. Mesoscale systems are extremely common in India around Jharkhand and West bengal regions during the month of March and April. In local terminology we call it “Kaal Baisakhi”
THE FALSE STORM- OUTFLOW BOUNDARY OF A MESOSCALE SYSTEM
OUTFLOW BOUNDARY- THE FALSE STORM
According to NOAA
A storm-scale or mesoscale boundary separating thunderstorm-cooled air (outflow) from the surrounding air; similar in effect to a cold front, with passage marked by a wind shift and usually a drop in temperature. Outflow boundaries may persist for 24 hours or more after the thunderstorms that generated them dissipate, and may travel hundreds of miles from their area of origin is called outflow boundary
Lets understand this in simpler words- A mesoscale storm is so powerful that it tears apart wind from its core and creates a rift between the warmer and the cooler winds . Often the force of the storm pushes the cooler winds outwards from the storm and the force generated is so strong that the cooler winds of the storm can flow away hundreds to thousand kilometres away from the main storm and impact a place where there will be no signs of any thunderstorms at all. In previous years also Kolkata has seen such Outflow boundaries created from Mesoscale system lying as far as Dhaka , Bangladesh
