F1's return to Sepang in Malaysia is shaping up to be an absolute nightmare for teams and drivers. The latest weather forecast shows a 75% chance of afternoon rain on race day, with the race kicking off at 3pm local time on Sunday. But that's only half the story. The tropical heat is looking like the real villain here, and it's going to create some seriously tough calls for the new generation of 2026 power units.

Here's where it gets gnarly. While air temperatures are expected to hit 33 degrees Celsius, the humidity of around 73% is going to push the feels-like temperature up to a brutal 43 degrees. For the 2026 cars with their new battery regulations, that heat means less electrical deployment when the battery gets hot. The drivers would have reduced energy to use on those two long straights at Sepang, which happen to be the main overtaking zones. That's a recipe for processional racing, and nobody wants that.

The heat also creates a genuine driver welfare concern. Cockpit temperatures could sit between 40 and 50 degrees, with track temperatures reaching 60 degrees. That's proper hot, uncomfortable work for whoever's behind the wheel. But the real kicker is what happens with parc fermé rules. Teams have to lock in their cooling configurations at qualifying on Saturday, and that's where the gamble kicks in.

If a team sets up for a hot, dry race and then Sunday's forecasted afternoon storm actually arrives, they're stuck with the wrong setup. If they hedge their bets on cooler, wet conditions and the day stays dry and humid instead, the battery could overheat and electrical performance tanks. There's no winning configuration here, just degrees of losing. Teams are basically going to have to guess right or suffer the consequences when their engines start to derate during the race. Welcome back to Malaysia, F1.