camping in Yosemite on short notice

a friend and I are going to try to visit Yosemite for a day later this week on a spur of the moment thing. It looks like all the camping options within the park are either full or not open. Anyone have some good beta on where to sleep? Are there any campgrounds right outside the park that aren't usually too busy? Any beta is greatly appreciated, thanks. 

First:  Check the NOAA weather report (9-17 inches of snow - though how much will reach the valley floor is always up for debate) 

• Tuesday: 
  • A chance of snow between 11am and 3pm, then snow showers likely after 3pm. Some thunder is also possible. Mostly cloudy, with a high near 44. Southwest wind 5 to 10 mph. Chance of precipitation is 60%. New snow accumulation of around an inch possible.
• Tuesday Night: 
  • Snow showers. The snow could be heavy at times. Some thunder is also possible. Low around 26. South southwest wind around 5 mph. Chance of precipitation is 80%. New snow accumulation of 5 to 9 inches possible.
• Wednesday: 
  • Snow showers, mainly before 4pm. The snow could be heavy at times. Some thunder is also possible. High near 40. Southwest wind 5 to 10 mph. Chance of precipitation is 90%. New snow accumulation of 3 to 5 inches possible.
• Wednesday Night: 
  • A 50 percent chance of snow showers, mainly before 10pm. Some thunder is also possible. Mostly cloudy, with a low around 21. Calm wind becoming south around 5 mph. New snow accumulation of 1 to 2 inches possible.
• Thursday: 
  • A 30 percent chance of snow showers after 10am. Some thunder is also possible. Partly sunny, with a high near 43. Northeast wind around 5 mph becoming west in the afternoon.

Second: 41 and 120 outside the gate spots might not be good depending upon the actual amount of snow that comes so that leaves...

Hwy 140 El Portal Bivy: For gray area car camping, after El Portal and just after Yosemite View Hotel on the north side of the hwy right before it starts to incline up to Yosemite (just before the Yosemite sign). iIn the middle of the week this should be chill. If you want actual camping spots, Yosemite Bug has camping areas in Midpines, a bit closer is McCabe Flat BLM Camping (FCFS)  in Briceburg after the winding descent after Midpines and before the bridge, even closer is Dry Gulch/ Dirt Flat Campground which is across the river from Cedar Lodge. 

Vaya con Dios, amigo

http://www.indianflatrvpark.com/accomodations.htm

This place has tent sites, it's right outside the park.  Not sure if the tent optiona are available this time of year/Covid, but it may be worth and email to find out.