Or maybe arrangements were made for staff to arrive before the red warning kicked in, and to stay on site? I've no idea, just wondering.
Local to me, the nuclear power station and it's ancillary facilities had a limited number of beds for people. In this weather, non-essential staff are told to stay away, and only process workers turn up for shift, with a one-in one-out process so critical processes are never unattended.
The water processing facilities don't have any accommodation like that, but now all have Remote Access to SCADA, so staff can monitor and control processes from home, and most will alert staff if there's an issue - they already do this overnight as they aren't (generally) 24/7 staffed. Most site staff will have some form of 4x4 transport provided, as well as comprehensive training on using it, including when it's better to leave systems tripped out than travel.
(I've not worked for either directly, but have supported both)
Similar. Office staff will be off/WFH if possible. Medical staff such as Nurses, Drs, HCAs, midwives are expected to get to and from hospital. During the last bad spell, one of the gynecology Registrars couldn't make it home from our local hospital so he went back to offer assistance and the midwives shoved him in a spare delivery room for a sleep with the threat they'd kick him out if they needed all 6 rooms - unlikely given the weather!
should it perhaps mean an additional public holiday for the affected area so businesses don't force people to travel and put their lives at risk unnecessarily,
Tesco announced they were closing all stores in red areas today for staff and customer safety. Seems fairly sensible to me.
What doesn't is my LA, who despite telling their own staff to work from home today were telling schools they shouldn't shut today and pupils should go in as normal. Utter folly, predicted windspeed of over 85MPH at my kid's school. Times like this I really miss my weather station - the anemometer seized up as it wasn't as waterproof as it needed to be for Cumbrian weather!