Downstairs lights keep tripping . Spark from consumer unit

[kerry19834]

Over the last few weeks my downstairs lights have been tripping randomly. The downstairs lights include a couple of outside security light on the circuit.

I think they have been tripping during heavy weather.

Today it happened again. When I went to switch them back on at the consumer unit there was a visible spark and they tripped at the consumer unit. I waited 30 seconds and they switched on fine.

I'm thinking there is an issue with One of my outside light. Given they seem to trip in wet weather.

But I'm worried about the spark from the consumer unit.

Should I turn off all My lights at the consumer unit

We had a problem once like this, and an electrician came round and we had to phone, I think, the National Grid . They came out within an hour and spent the evening sorting out the power supply to the house, which was fluctuating and causing the tripping. Lots of vans and lots of men in cherrynpickers going up and down the telegraph posts to the electric cables
You will need a qualified electrician round first to check your house and if there is no problem, they will recommend you call the NG people.
It did cost the call out fee for the electrician, but was worth it

Agree you need to get a qualified electrician round for advice @kerry19834

Do the outside lights have their own switch ?
You say downstairs lights are tripping, are the upstairs lights on their own circuit?

It does sound like the rain is getting into a light or the cabling outside and shorting , do you have a step ladder to get close to the lights and have a visual inspection?

Is there a bathroom above the fuse box? Check if there's a leak under the bathtub

I was thinking of something like this, maybe water dripping onto a ceiling light but OP saying it happens with bad weather ( rain ) does suggest outside lights.
But I’d expect those outside lights to have their own switches inside the property so they could be at least turned off completely. Which would help to work out which one was causing the problem.