Climate change is moving water around, not creating or destroying it. Warmer air holds more water, so overall, the atmosphere can hold (and at times drop) more water than before. Permanent ice is melting as well, so that puts a bit more fresh water into the air and ocean. The water in the atmosphere is constantly circling the globe, forced largely by the rotation of the earth. Warmer temperature also makes for more evapotranspiration, so more fresh surface water is pulled into the air. But that same water will eventually fall elsewhere.

The sun is the source of energy that drives wind, rain, and evaporation. When you trap more of that energy with GHGs, it just turns up the volume for all of those things. There’s always seasonal and geographic variability, but the extremes increase because all those phenomena are solar powered.

Flash floods happen because dry soil doesn't absorb water very fast.

Here's a video with a visual. https://www.youtube.com/watch?v=urQHsOmoKLg

Very little water ever leaves the earth via the atmosphere, so most of the water goes to the oceans or to other places.

https://www.yahoo.com/news/rare-june-atmospheric-river-takes-134720481.html

https://www.cnn.com/2024/06/03/world/video/nairobi-kenya-flooding-rain-runda-madowo-pkg-digvid

https://www.reuters.com/world/europe/rescue-worker-dies-southern-germany-floods-2024-06-02/

https://www.newsweek.com/pittsburgh-rainfall-record-flood-1906267

Record droughts in some places, record rains in others. Regular patterns breaking down means the extremes get more extreme, the swings get more rapid. That's not good news for anything.

I'm not an expert, but it's a very complex global system with moisture in the atmosphere sometimes falling as rain/snow, collecting in rivers and lakes, going into ground water/aquifers, flowing into the oceans, and sometimes just staying as moist air. If one area isn't getting it's usual rainfall, quite often another area is getting more, but it can also be that the moisture is just in other parts of that complex system. A lot is driven by high- and low-pressure systems, air temperature, water temperature, etc.

In my area of southern California, we've had some major, extended droughts. But the rising temperature of the Pacific has caused the air to hold more moisture, and we've also had some "atmospheric river" storms that drop insane amounts of rain. So even though we get an average of 13 inches of rain a year, we got more than 13 inches in just February, and we're up to almost 31 inches for the season. It wouldn't be surprising if we didn't get anymore until late in the year though.

Some of that rain went into snowpack, some into reservoirs, some into ground water, but we're close to the coast and all of it will go back to the ocean. Did we get rain that would normally have gone elsewhere, or was it rain that wouldn't normally have formed? I think it's likely hard to say, but maybe there are meteorologists or others who know more reading this.

Well, for the most part, it's just flowing into the ocean, like it always does. Evaporation over land is a very minor part of freshwater loss.