When Is A Storm A Storm?

[Wet'n'Dry]

I usually frequent the UK convective discussion topics, but one thing I have noticed is some people insist on one flash of lightning and a distant rumble to be a storm!!

This year I have had at least 5 convective days that produced a rumble and the odd flash, I never considered any or them to be a storm, however forum members around me have added storms to their profiles where in my opinion no storm occured!

So what defines a storm?

Edited May 23, 2012 by Wet'n'Dry

[I remember Atlantic 252]

its in the no storms club thread, ive had 2 half hour storms, 5 flashes of lightning and thunder, and im classed as out of the club, 1 flash in a 5 minute shower, then still in the club, not classed as a storm

[Thundery wintry showers]

The official Met Office definition of a "thunder day" is a day with at least one rumble of thunder, but there is plenty of scope for individuals to come up with their own definition of a "proper storm", including the classification that allows inclusion in the No Storms Club.

Standards will vary- here in Cleadon it feels like an achievement merely to have significant overhead convective activity, let alone a rumble of thunder or flash of lightning- there was a phase during late April/early May when during sunshine-and-showers days the Tyne and Wear coast remained stubbornly convection-free, due to the winds off the North Sea.

[A.J]

IMO to be classed as a thunderstorm, a cell needs to last at least 20-30 mins in situ, with visible lightning and audible thunder throughout the duration, anything less is a thundery shower

[Aaron]

Going by the above definition I'm afraid most people in the UK will have been in the NSC for the past 5 or 6 years.. remember we're an island and what we call a storm might be a breezy day in oh I don't know Minnesota.

I'd consider 10 - 15 minutes of torrential rain with frequent thunder and lightning a storm

[Keraunic]

What happened to the overnight storms EA used to get. When I still lived in York they always seemed to be getting at least one per year. (in the 90s ) soon as I move down here that's it.

[Tim B]

IMO to be classed as a thunderstorm, a cell needs to last at least 20-30 mins in situ, with visible lightning and audible thunder throughout the duration, anything less is a thundery shower

This.

For me to classify something as a lightning storm it needs to have had numerous lightning strikes no more than 3 to 5 minutes apart and last a reasonable amount of time, anything else is just a weakly electrified cloud. Ideally it should have thunder too but since you can observe storms at night from a long way away (at least from the higher points around here) this isn't a requirement for me.

What happened to the overnight storms EA used to get. When I still lived in York they always seemed to be getting at least one per year. (in the 90s ) soon as I move down here that's it.

I've wondered the same, we never seem to get as many these days. I got one last year though it wasn't as powerful as the ones I remember in the 90s, they never seem to be these days.

[ZONE 51]

Could i add that the speed at which the storm travels through plays a part in what we could define as a thunderstorm.

One single cell can last 20-30mins average, producing a few rumbles or many over that time period, a group of thunder showers with each shower giving the odd rumble could sound like a storm.

I like to be able to detect the thunder or lightning at least once every 5 minutes to class it as a thunderstorm and over at least the single cell 20-30mins time-frame, and prefer it that the thunder is quite loud to log it as a local(within 3 miles for example), although that would be a weak storm in my book, one flash or rumble/bolt cracker every one minute would be quite a good one!

[Keraunic]

I remember a very severe storm in the Spalding area of Lincolnshire on May 30th 1969. Wow that one was spectacular with very severe lightning and a farmhouse was hit just across the fields from us. That had to be a supercell.