Advice needed for unexpected freezing weather in late May

[otterprods]

Springtime in the Rockies means some really crazy weather!

It's been in the 70s and 80s here for a few weeks now so I just de-winterized my RV's water system. But now suddenly, in late MAY, we're expecting up to 15 inches of snow and overnight temperatures as low as 23°!!! I could use some advice on how to handle this without totally re-winterizing everything. Or perhaps just a 2nd opinion for my own plans. My plans:
(1) Leave the grey and black tanks as is because they still have mostly anitfreeze in them (I flushed it out of the lines but did not dump yet)
(2) Put an ultraviolet space heater + fan in there and let it run overnight (I could turn on the furnace too but I'm a little worried about anything with a flame running while I'm not in there)
(3) Open cupboards and things so that the warmer air flows everywhere possible
(3) Turn on the water heater (electric mode)
(4) Leave the fresh tank full and the water pump on so I can let the water trickle out periodically

Thanks in advance for any responses

 

[marc2912]

turn heat on, camp in the RV overnight. I wish I had a better solve but freak weather calls for last minute changes

 

[otterprods]

turn heat on, camp in the RV overnight. I wish I had a better solve but freak weather calls for last minute changes

Thanks for the reply, Marc. The only issue with staying in it overnight is that I really don't want to slide out with 15 inches of snow in the forecast. Without the slideout the sleeping situation is not great.