Alex de Angelis was leading the Moto2 Friday practice timesheets in Malaysia when the usual late-afternoon storm arrived at Sepang shortly after the halfway mark.
That would have confirmed the Sammarinese as fastest for the JiR team, but de Angelis made sure by getting back out on track at the end of the session - when conditions had improved - and pushed his advantage up from 0.058sec to 0.188sec on his very final lap
Scott Redding of the Marc DVS team kept up his consistent front-running form by being nearest to de Angelis.
World championship leader Toni Elias was a fraction slower for third on his Gresini Moriwaki, with title rival Julian Simon one place behind for Aspar Suter.
Elias is 81 points ahead and will be a world champion for the first time if he can leave Sepang with a lead of at least 76 points over Simon.
The nearby thunderstorm didn't just bring light rain, but also knocked out some of the TV cameras!
Friday practice - Sepang:
1. de Angelis (MotoBI) 2m 9.586s
2. Redding (Suter) +0.188s
3. Elias (Moriwaki) +0.249s
4. Simon (Suter) +0.390s
5. Iannone (Speed Up) +0.397s
6. Luthi (Moriwaki) +0.447s
7. Rolfo (Suter) +0.604s
8. Corsi (Motobi) +0.667s
9. Aegerter (Suter) +0.906s
10. Faubel (Suter) +0.919s