Former Rockstar Developer Reveals How GTA 3’s Weather System Came to Be

Obbe Vermeij, a Rockstar Games veteran who helped bring the iconic worlds of Grand Theft Auto 3, Vice City, San Andreas, and GTA 4 to life, recently took to Twitter to share some interesting details about building GTA 3’s weather system.

Vermeij’s post dives into the game’s early weather mechanics, revealing a system that relied on pure chance for transitions between the four weather types: sunny, cloudy, rainy, and foggy. This seemingly simple approach resulted in unpredictable weather patterns, with testers reporting long stretches of the same weather condition.

There are 4 weather types in gta3.
Sunny, Cloudy (overcast), Rainy & Foggy. Each in-game hour, a new weather type is picked. The transition between weather types takes 1 hour.

Initially, I used a random chance for each transition between weather types. Ie 40% for Sunny->Sunny,… pic.twitter.com/BP18WjolXI

— Obbe Vermeij (@ObbeVermeij) June 21, 2024

To address this, Vermeij implemented a more controlled system. GTA 3 now cycled through a pre-defined sequence of weather types, ensuring a more consistent yet dynamic experience. This system also empowered level designers to tweak specific missions, overriding the default weather with script commands. This proved crucial for missions where rain, with its slippery streets, could potentially throw off gameplay balance.

Vermeij’s tweet also hints at the evolution of weather systems in later GTA titles. Notably, Vice City introduced a “Clear Sky” option, offering a sunnier experience compared to the standard “Sunny” with its light cloud cover.

Vermeij, now retired from Rockstar Games, has become a bit of a Twitter star thanks to his insightful dives into the creation of these beloved GTA titles.

He has weighed in on the mind-blowing 8-minute speedrun of Vice City, explained the ingenious way vehicles spawned in the PS2 open world when there were critical hardware limitations, and even gave insight to the enduring mystery of the vanishing pigeons in GTA 3.

With each Twitter post, he offers a glimpse into the creative problem-solving that went into making these classic GTA games.