Rain? Today? In the UK? In Hertfordshire? Quite surprising, but it can happen.
None here in Lincolnshire and looks like being yet another fine day.
Weather.com gives 0% chance of rain until 02:00 tomorrow, for our patch, when the forecast gives just a 5% probability.
Gridwatch is showing 3 1/2 GW for solar, currently – a little less than this time yesterday. So any rain will, I suspect be transient and light.
No heavy rain, yet, to help fighting against moorland fires.