This weekend's Turkish Grand Prix will serve as the latest battleground for Max Verstappen and Lewis Hamilton's race for the 2021 F1 title race. Hamilton, who has a two-point advantage over the Dutchman, will be looking to extend his lead over the Red Bull driver.Verstappen will be hoping for the exact opposite as he'll be seeking victory after being on the backfoot in the previous race in Russia due to an engine penalty. The 16th race of the season is expected to throw in a surprise or two which could mix up the results quite a bit.With that in mind, here are the top five reasons why the 2021 Turkish Grand Prix is a must-watch:#1 Red Bull or Mercedes - Who holds the edge?Sky Sports F1@SkySportsF1"They've just been too strong" 💪Lewis Hamilton talks form, upgrades and Red Bull ahead of the #TurkishGP #SkyF1 | #F16:16 AM · Oct 7, 202198759"They've just been too strong" 💪Lewis Hamilton talks form, upgrades and Red Bull ahead of the #TurkishGP #SkyF1 | #F1 https://t.co/vkw59lNvW5Being a venue that was pressed into service after a 10-year absence in 2020, the teams struggled to find their footing on the Istanbul Park circuit last year. A brand new track surface turned the pecking order on its head after drivers found it tricky to extract any kind of grip.Consequently, we were treated to the unlikely spectacle of Lance Stroll starting on pole for Racing Point. Mercedes were nowhere close to the ultimate pace to begin with but Hamilton somehow managed to eke out a win and called the surface "S*it" afterwards!Although the Turkish Grand Prix organizers have assured teams and drivers that the track surface won't be a cause for concern this time around, the proof will, as they say, be in the pudding. Until the cars run some laps around the track, it's impossible to predict what's going to happen.#2 We might have a wet Turkish Grand PrixFormula 1@F1Bring an umbrella, just in case... ☔️#TurkishGP 🇹🇷 #F1f1.com/TUR21-Weather11:03 AM · Oct 7, 2021244793Bring an umbrella, just in case... ☔️#TurkishGP 🇹🇷 #F1f1.com/TUR21-WeatherThe 2021 season is a gift that keeps on giving and another one that could well be on its way is the weekend forecast. It just does not look good if you're a fan of a straightforward dry race.According to weather forecasts, there is a possibility of rain during the Turkish Grand Prix weekend. Should that transpire, expect the on-track action to get sprinkled with a fair bit of unpredictability for added measure.We've had rain play a part multiple times this season. On those occasions, the cream has risen to the top, with drivers like Max Verstappen, Lewis Hamilton and Lando Norris separating themselves from the pack.If the Turkish Grand Prix forecast holds true, we should be treated to yet another driving masterclass by one of the usual suspects.