"Jake
In reply to James Young's answer - My question was in reference to what happens in F1 when it rains during the race (after the start or lap 2 or 3)? - Do all the drivers pit at the same time thereby causing the above problems? or is this managed some other way? I assume fairly early on in the race all the cars are still pretty close together.
The teams and drivers decide amongst themselves the best time to pit and what tires to take. It's a matter of determining/guessing the conditions as they presently are and as they will become. Is it light rain? Heavy rain? Is it going to rain for 10 minutes, or for the next hour and a half?
If the conditions change mid-race it's about determine which tire best suits the conditions, both now and later on.
For instance, in the game I recently had a race in Singapore where it started raining with about 3 laps to go (30-lap race). Some of the teams I was racing against pitted to change tires, be they Inters or Wets. I was running a one-stop on Soft tires and decided to gamble on staying out, because I thought the pit delta was longer than any time I would gain by being on the right tire (which turned out to be the case).
http://igpmanager.com/play/?url=race-result/101888/39508 <- my race (it's my B-team)
You can see how I start losing about 5s/lap in pace between laps 27 and 28, but I'd figured the pit delta at Singapore to be 21 seconds, so staying out seemed to be the way to go.
By comparing two other drivers that were in the same race...
http://igpmanager.com/play/?url=race-result/101888/33136 -vs.-
http://igpmanager.com/play/?url=race-result/101888/25156
Schwarz and Duchovny both pit for tires with two laps to go; Schwarz takes Inters and Duchovny full Wets. Schwarz runs about 1:40 flat on the last lap, and Duchovny a 1:43.2. This seems to indicate that the Inters were the way to go, and the fact that Schwarz overtook Duchovny on Lap 29 seems to bear this out, Schwarz's lap 29 being about 4.5s faster while they had been running similar times when both on Softs.
The game tries to simulate this aspect of guessing the conditions via the Advanced Strategy, the idea being that you guess how long it needs to rain in order for a wet compound (Inters or Wets) to be faster than your current dry tire, and then how long after it stops raining until the dry compounds become quicker again (if the race goes dry -> wet -> dry).
Kind of went off on a tangent there but hopefully you get my meaning.