Spots and discolouration on vegetable plants - cold damage or fungus?

[emmakathleen]

I'm a newbie gardener. We just had a pretty severe weather change where I live from 28C (82F) and dry to 4C (39F) and rainy in two days. It is now back to 20C+ (68F) highs. A couple of days later after the short cold snap and I've noticed our plants have spotting and discoloration on the leaves. Warm weather plants like my tomatoes seem to be the most affected. Does this seem like fungus or cold weather damage or maybe something else (photos attached)? I'm having trouble diagnosing through Google searches! Thanks so much to anyone who can share advice

 

[Logan]

Hello and welcome to GF
It looks like that it's just temp change but the yellow leaves of the tomatoes looks like they're running out of nutrients, if you have not long planted them they should recover.

 

[Tetters]

Welcome, it would be easier to answer your queries if you would update your profile with your precise location please

 

[emmakathleen]

Hello and welcome to GF
It looks like that it's just temp change but the yellow leaves of the tomatoes looks like they're running out of nutrients, if you have not long planted them they should recover.

Thanks for the advice @Logan!

 

[Logan]

Thanks for the advice @Logan!

Your welcome

 

[Tetters]

I`m concerned about those white spots that are showing mostly on your fourth photo. This could indeed be the start of powdery mildew and will need attention.
Weather changes can really mess things up, and could very well be what has caused the problems with your little plants.
Do you have a greenhouse? We keep our plants under cover until we`re sure about the outside conditions. Cloches can help.
Thank you for updating your profile @emmakathleen, it will make things so much easier for gardeners on the forum who live in Canada and the USA. We do seem to attract members worldwide and it`s very easy to dish out the wrong advice