I would say what you describe was entirely a fluke.
I did a short course on understanding the weather, as part of my free choice bit, when I studied with the Open University.
They do have extremely powerful computers at the Met Office and also they do something called modelling, where they input lots of current data, press a button, and see what the computer comes up with. Interestingly, they think that if they'd been able to do modelling, back in 1987, they may have predicted that terrible storm.
The thing is, according to the Met Office, they predict many aspects of the weather very accurately these days; things like humidity, wind direction/speed, temperature, air pressure, but what they are bad at is predicting precipitation, because that can occur very locally. Unfortunately for them, this is the bit that everyone notices, so it gives people the impression, that their abilities are worse than they are!
Also, as you can see above, the weather is multifactorial. All of those factors can play a part in determining how our weather pans out. So, it's actually an extremely challenging area of science. By the way, I use the Met Office's own app, because it's much more detailed than the BBC one.
For those who don't know, in 1987, there was a notorious hurricane, which the experts failed to see coming...
“Do what you can, with what you have, where you are”. Theodore Roosevelt