Alabama Hills is basically in the shadow of the Sierra Mountains and that proximity can generate some pretty unpredictable weather. I camped there at the end of April and experienced high winds, snow flurries, heavy overcast, moderate rain, sunny skies with no wind, and a thunderstorm with several nearby lightning strikes all in the span of three days. On average the weather should be nice at that time of year, but check weather forecasts and be prepared for cold or rainy conditions. Death Valley receives little rain and the rain is infrequent. Flower seeds can lay dormant for years until a large rain event and then the area explodes with growth over a short period of time. Owens Valley receives three times the amount of rain with the bulk of that arriving in the winter and early spring which leads to a wildflower bloom that's less intense and spread out over a longer period of time.

Just got back from a few days. It ranged from low 30's to mid-60's. On the first and second days, it was clear skies, but windy. It would not be fun in a tent unless you were shielded by any rock formation. The winds will also change, but continued to blow from the East. The last day was below freezing with no wind. Lastly, be mindful of your route as well. If you're coming from the North on the 395, know you're going through the Mammoth and Mono passes which can have dramatic weather changes in the valleys. We went through Mammoth and the chain requirements were active and we were passing through in the night. Read: Don't just check the weather to your destination, check your route as well and have a contingency plan if you chose to travel during this time. As noted, this area in the Spring and Fall can have dramatic weather swings and wind. Be prepared. April would seem to be a good time, but know you're still susceptible of these weather swings. I shouldn't be in April. According to the almanac it's going to be upper-50's to mid-70's. I'm ignorant of the floral question.

You'll want to check the BLM website or call. The BLM is currently in review of implementing restrictions on dispersed camp in the Alabama Hills.

March/April are beautiful and usually mild there...with that being said, it is a La Niña year, which may bring a lot of rain into those months and I don’t recommend the roads if/when they are saturated. Just keep an eye on the weather and enjoy!

We've never been there that early in the year as we still work through May or June, but I would think it would be a good time.

Ridgeback12, Sorry, I can't help with that time frame, as I was there in October, the trees on top of Mt Whitney were in Fall colors...

April could be perfect weather-wise although things are beginning to warm up that time of year. With all the lock-down associated with COVID I’ve witnessed via internet searches the number of people has significantly increased. (Check out the Long Long Honeymoon YouTube on AH for video). Will it be as crowded as a state campground or National Park? Never. But there will be more people searching for a place to camp than pre-COVID. As for wild flowers, others may be able to speak to this more than us, we have not had outstanding/memorable experiences with wildflowers in the AHs and have been there at all times of the year except for summer which is HOT! Hope this helps.

April should be great. I was there end of March and it was cold at night and very windy. We were in a tent, so being in an RV would be ideal. I am not experienced with Death Valley to answer your other question

I don't know. That was my first time and first review of the area. I can say that if you go during the week, there is no crowd.