Tonight there will be a lunar eclipse when the Earth is between moon and the sun and it's shadow moves across the surface of the moon. This will be the longest total lunar eclipse this century so there is a good long time for totality. Totality will last for nearly and hour and three quarters The moon will take on a reddish tinge as the suns rays pass through the Earth’s atmosphere.
However, the cloud will be problematic. Have a look at the forecast image for low and high cloud associated with frontal rain in the west and thunderstorms to the east. SW Britain seems most likely to get breaks in the clouds, elsewhere you will be lucky. But have a go. Mars will be very bright and red in the sky near to the moon, just SE in the sky. It is at its closest point to the earth so if you do get a clear slot this evening you could have a stunning celestial view.
July 27, 2018
Partial eclipse begins: 18:24 UTC 7:24 BST
Total eclipse begins: 19:30 UTC 8:30pm
Greatest eclipse: 20:22 UTC 9:22pm
Total eclipse ends: 21:13 UTC 10:13pm
Partial eclipse ends: 22:19 UTC 11:19pm
It will be a balance of the moon rising, how dark it is, the timings of the eclipse and the cloud cover. In London, the moon won't rise in the SE until 20:49 BST in Edinburgh until 21:22,