I’ve been using the default Apple Weather app since getting my iPhone earlier this year. It’s been fine but over the last few days it seems to be less accurate in general.
I’m in Ireland if that matters.
Edit: Updated the title to include iOS specifically
Give Weawow a go. There’s a website (https://weawow.com/) or a free (and ad-free) app. It’s gorgeous and pretty accurate (I’m in the UK).
I use the default app or the Environment Canada app, which is specific to Canada.
I like Carrot, but primarily because I like the cheeky quips. That said, it is extremely full-featured and if you pay for a premium version you get a ton of additional features. If you turn off the cheeky quips it really feels like what Dark Sky would’ve become had Apple not killed it.
Windy.
Breezy Weather
Open source, light and elegant design. Perfect amount of customization.