Sure. I welcome weather. The basics of weather are temperature and wind. Some of the more advanced content would be your rain, snow, and fog. Extremes would be standing water and mud. How PD wishes to implement this is up to them. Let me revisit some games with weather effects...
--- Weather Effects in Some Games ---
Le Mans 24 Hours - You have to race the different championships to really sense changes in weather. I usually put on Intermediate Tires in the later championships because like Houston in the Summer- a chance of rain almost every day. The rain drops weren't glorious, but you really sensed the drops of rain on the track. Every rain storm seemed like a monsoon. And if it rains, you don't really see much difference in the skies when it's night.
Pro Race Driver and the ToCA Race Driver Series This Codemasters series of games have had some... somewhat okay rain. Pro Race Driver is a game I absolutely hated for its AI. Its rain effects were completely unimpressive. ToCA RD 2 had better rain fall. The skies looked pretty nice, and you could actually notice rain falling on the cars and the road. There were still 20 cars to a track in these conditions for those whose max car count is 20 cars. ToCA RD 3 was very nice. I stated that the rain fall in that game was like stars falling from the sky. Real beautiful effect. None of the rain fell on the track or cars for what I know.
Enthusia Professional Racing - Enthusia had a few wet events. I consider Marco Strada's wet night race (I'd want to race it on a dry night) as one of the most beautiful lighting examples of almost any game out there. Race Marco Strada's night race in the rain. You begin to take notice of how everything sparkles beautifully from that ship and from some of the street lights. It is an absolutely beautiful effect. Enthusia has something GT4 and Forza 1 didn't- a wet race with a full grid on the track. Tsukuba had this lined up for you. Counting direction and time of day, you could race four tracks with a full grid of cars... all at Tsukuba. There was also Wintertraum that shown off racing in the snow. And if you thought the cars handled like they are on ice, try racing this track. Case closed.
GTR - I tried Monsoon Rain in some GTR races... and the cars were absolutely tough to keep on the track. I even ran Spa-Francorchamps in the nighttime, and in addition to not being able to keep the car on the track, I couldn't see a damn thing! This would be absolutely unfair to race if monsoon rains were in GT5.
--- Rain ---
RacingFreak2k3 mentioned how the rain from PGR4 looked. I love Gran Turismo, but I have great respect for the Project Gotham Racing series. The rain effects were absolutely amazing. You saw rain pick up on the cars. You could say that while GT5's motto is "The New Standard," PGR4's become the new standard for rain graphics. Could you imagine racing Le Mans (not necessarily the endurance) in your Nissan R92CP with pounding rains? Poetry in motion. I stressed this in other posts... PD will need to incorporate rain tires as well as study how cars handle in wet conditions. That means driving certain sections of tracks. It rained at Burke Lakefront Airport for a Champ Car race once. The Cleveland, OH airport track has some painted parts of the runway which actually become slick with a lot of rain. If done right, street courses would be a nightmare. Even more so with open-wheel or completely fragile cars. A way around it would be if GT5 featured a track that was soaked with rain. We know we had this before, but imagine a track drying out. You'd have to find a dry line to follow as the track dries out. As much as I am not a fanatic of the Nürburgring Nordschleife, I appreciate all the racers who take on the challenge of that track even in the pouring rain. I'm very okay with drizzle. You'd need your intermediate or light rain tires to handle effectively.
--- Snow ---
Let's imagine that a lot of snow falls at Chamonix or it snows atop (granted we get this track) Pikes Peak. I would be game enough to race in a proper rallycross event in the mold of the Andros Ice Racing series. Just bring back the Opel Tigra Ice Race Car and all will be fine with me. ^_^ Then again, I'd be interested in a rally section in Sweden like in the WRC. I even imagine if the Swiss Alps had snow falling. A dream track in the snow would be a track at sunset covered in snow as skies clear out. Some snow flurries would be a nice start. Anything like a snowstorm or [especially] a blizzard would have to include intense snow. Let's say in a weird scenario that PD includes races in the Pacific Northwest (other than Seattle). Or let's say Seattle gets a snowstorm for a race. Maybe imagine if PD includes Alaskan locales such as Juneau, Anchorage, or if they are brave- a rally race in Barrow, AK (northernmost settlement in America) or its neighbor, Point Barrow, Alaska (northernmost point in America). There would have to be great amounts of snow.
--- Other Features ---
Most features that I wanted to bring up was part of my environmental studio <
https://www.gtplanet.net/forum/showthread.php?t=87712 >. These other weather features would include fog, dust storms, hail, freezing rain (Houston had plenty earlier this year. Even freezing rain on my birthday!), sleet, and that sort of thing. The game calendar would have to be realistic in terms of climate. You wouldn't expect a 100 degree Farenheit day in Seattle or Reykjavik, Iceland in late December, would you? Or would you expect -30 degrees Farenheit with snowfall in Miami... in June? Any precipitation on ovals usually would mean that races wouldn't take place. Think of racing ovals like trying to race the short courses in the daytime in "Tokyo Xtreme Racer Drift 2"- you can't race those events if there's anything other than daytime and clear conditions.
All in all, I'd welcome weather. I just realized this was an expectation thread. And as usual, I don't believe in expectations. Just let PD do the best they can in providing weather effects.