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All about winter thunderstorms

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Is there thunderstorm in winter?

One of the most common assumptions about thunderstorms is that lightning strikes most often in summer.
That is true, but we must still weigh that answer.


Thunderstorms are not only present in summer, thunderstorms also strike throughout the year..
What we call winter in meteorology covers the months of December, January and February, the coldest period of the year in the northern hemisphere1

How often do thunderstorms occur?

As noted earlier, thunderstorms are very common in the summer.
Compared to other seasons in Western Europe2, the proportion of lightning flashes in summer is 66%, whereas in winter it is only 2% (16% in spring and 16% in autumn)

However, the few thunderstorms that occur in winter should not be underestimated, as winter thunderstorms are the most violent thunderstorms in Western Europe.

The proportion of lightning flashes we will call “very violent3” (above 100 kA) is 58% in winter, compared to “only” of 9% in summer (and 10% in spring and 23% in autumn).

Thunderstorm seasonality

What is the difference with summer thunderstorms?

As a reminder, in a previous article we mentioned the conditions for convection: Thunderstorms form when the air mass is said to be unstable. That is, when there is hot air near the ground and cold air at altitude.

In summer the thunderstorms are called “hot air mass” with a mass of air made unstable by very hot low-lying air and humidity.

In winter, however, the conditions that must be met for a thunderstorm are very cold air at altitude that conflicts with the soft (or hardly fresh) air in low layers.

An example in France with the comparison of lightning density and amplitude, in summer and winter season.
You can notice that violent thunderstorms (>100kA) are more common in winter, although there are fewer thunderstorms.

Lightning density and average lightning flash amplitude in winter
Lightning density and average lightning flash amplitude in summer



>> Focus: The Mediterranean episodes.
Characterized by their sudden onset and high precipitation, the Mediterranean episodes are violent stormy systems, often causing localized flooding.

Good to know :





No matter the season, summer or winter, you should be vigilant in the approach of a thunderstorm and not underestimate the violence of a thunderstorm in any season and in all latitudes …





Turkyan Marinov
File written by Turkyan M.
She is our expert in the leisure sector.
Interlocutor of several federations of the leisure and tourism sectors with which Météorage is in partnership or adheres, her experience of more than 5 years allows her to understand their constraints and specific stakes.

>> Would you like to learn even more about the topic? <<
Email the author of this blog at: allaboutstorms@meteorage.com


1More information: : “Comprendre la météo”
2Western Europe currently covers the following countries: France, Spain, Portugal, United Kingdom, Ireland, Belgium, Luxembourg, Netherlands, Denmark, Germany, Switzerland, Italy.
3The average amplitude of a lightning flash is 20kA