I wash outside with a foam cannon and pressure washer. But wasn’t sure about temps. Typically I try to wash when it is above 50. Is 45-50 degrees too cold? Will the water at that temp affect the paint?

 

Should be totally fine. I wouldn't wash in freezing temps but 45-50 is a similar effect to driving through the rain at that temp. Obviously you're getting more water into seals and such, but Porsche winter tests these cars.

 

40s are fine. Be sure to get yourself some Frogwear gloves.
I hand wash my cars all year round, until the temps dip into the 30s and below.

Paint isn’t affected by the water in the cold. People drive these cars in single digit (F) temps and snow. Unless you’re blasting hot water onto a cold surface, you’re not going to have any issue. These things aren’t fragile.

 

You will be fine. Your tap water temp is probably 50-60 degrees so not really a big difference. I would not use hot water when it is freezing out as that could potentially cause the glass to crack.

 

There's also the no rinse options:

https://optimumcarcare.com/product/o...se-wash-shine1

https://ammonyc.com/products/ammo-frothe-hoseless-lift

I've heard great things about them and people that know a hell of a lot more than me about detailing swear they're safe and effective. I bought the Optimum product but have yet to use it, but at least one other on here gave it a recommendation that prompted me to buy it.

 

I used Speed Shine from Griot's Garage: https://www.griotsgarage.com/speed-shine/ yesterday and was very pleasantly surprised with the results. I "washed" my entire car in about 30 minutes, in the garage, with temps outside in the 20's. I used 3 new microfiber towels and the product, then cleaned the glass as usual afterwards. Fantastic result! Fortunately my wheels weren't all that dirty so I didn't have to clean them this time around.

 

Thanks for the responses. Washed my car in almost dark last night when it was 45-49 degrees out. To quote Cuba Gooding Jr. "I air dry." I took it for a quick trip up to 110 to get the water off. Looks pretty good for a quick clean.

Thanks for the no water suggestions, but I currently use an almost no contact method to clean. Foam cannon without a pre-rinse. Then a complete rinse. Then a drag dry method with some large high quality towels. No sponge/no scrub and no rub dry to avoid swirls. Those videos for the Ammo, etc. show a lot of rubbing on the dirt which I would avoid.