In view of all the foul-ups, bugs, and disappointments of every pack released to date, do we really want the current team to tamper with the weather? Unless they are exceedingly much intensively careful about quality control I can easily see things such as: rain = massive flooding, perhaps all animals proceeding in pairs to the nearest boat; snow = single floor homes buried up to the housetops, multiple story homes accessible only via upper floor windows (this happened to my late wife several times while she lived in PEI, Canada); hail = one stone will kill a sim instantly, outside objects destroyed, roofs holed and badly damaged; lightning = massive fire storms akin to late WW2 incinerating everything. Weather is a powerful thing, a force that ever reminds humans just how puny and powerless we really are. Sorry to say, but the performance of TS4 to date does not give me confidence that seasons in it would be of the same quality as in TS2, enough to know there was weather, but not overwhelming in its effects.
