I was on a flight into London during storm Henk. We sat in Berlin for 90mins waiting for a predicted lull because at our takeoff time the wind here was too strong.
I was sitting in the front row, and the crew kept the pilot door open throughout that 90 mins. The pilots were keeping up a running commentary about flights attempting to land in London - "nooo he's not going make that! Off he goes again! What's he doing now?! That Amsterdam one isn't taking off is it?" so they clearly had access to something - though might have also been flightradar on their phones ;-)
The final decision to take off was a -"oh come on, let's give it a go, no point sitting here!" ...