i was gonna take my volvo to college today to sort the exhaust but it wasnt having it tried a different battery and jump starting it but nothing just kept cranking got home at lunch and it starts up straight away. my thoughts was moisture in the distributer or something, anybody know what could be causing this?

Check fuel and spark. Unfortunatly it's hard to pinpoint seeing as it "fixed itself", could have been a loose connection or lack of fuel pressure or many other things...

hopefuly it wont rain all day 2morow and i can start an investigation