More frequent and intense weather extremes are expected as a result of climate change, with Wales facing the prospect of wetter, wilder winters more often.
Meanwhile, this year scientists are monitoring the El Niño event over the Pacific Ocean – which set to be “strongest in living memory”.
The powerful natural climate phenomenon pushes up global temperatures and can increase the risks of extreme weather.
While this does not automatically translate into bad weather in the UK it is “part of the picture” that is leading to concerns for the coming months, according to Jeremy Parr of NRW.
“We do invest in flood defences… but you can’t stop all of the flooding all of the time,” he said.
“So that means that people need to think the unthinkable really – or the unpleasant – and [consider] if it were to flood around where I live, what would I do?”
“Time and time again” the organisation was told by people who had experienced devastating flooding that “they’d never flooded before, and didn’t think it would happen to them”, he added.
NRW advises people to check their flood risk by postcode online, external, sign up for flood warnings and access advice about what to do, external if flooding is forecast in their area.
The organisation’s flood warning service is available to 181,158 properties in Wales, but new figures show just 48,844 were currently signed up to receive the alerts via phone or email.
“It is low – 27%,” Parr admitted, suggesting that people may be being put off by myths that signing up could affect their insurance premiums.