DS (2.7) has a rash on his torso. It disappears under a glass so not worried from that point of view.
It's a mottled rash with ever so slightly raised bumps on his skin - kindof like your skin goes if you stand under a hot shower then go into a cold bathroom - not the first bright red but the cooling down skin red (if that makes sense!).
He doesn't have a major temperature, but it is slightly raised for him (37.3 versus his usual 36.4/6) and he seems fine in himself - still as stroppy and grouchy as a toddler can be 
He also has a major nappy rash going on due to some nasty nappies - 4 poo's today as opposed to his normal 1 or 2, but only 1 yesterday.
My immediate very over the top PFB response is to rush him to OOH, but my saner response is see how he is overnight and then decide.
If it is the same tomorrow as today, WWYD? (If it helps, he's supposed to be attending a birthday party on Saturday for one of the children he goes to nursery with - I'd like to be sure he isn't contagious!)