You really don't want flaps on a windy day. You want the opposite or spoilerons. Some radios call them air brakes, as has been mentioned.

I set a Flaperon wing type, then mix throttle-master and Flaps-slave. I set the spoilers to move up instead of down. If you have the large ailerons, 3 inches or more, start with an inch of movement. I set offset so they start at half throttle and are fully deployed at idle. They are armed with a switch.

When I am ready for landings, I flip the switch on and when I throttle back, both ailerons (spoilers) move up. If I have to add power for a go around or a touch and go, they drop down at half stick automatically.

Spoilers, or spoilerons, work very well on windy days and in cross winds. Your plane seems to cut right through the wind.

If you think of 3D, you are really doing a very slight elevator. With a lot of spoiler, 30-45 degrees, the plane will make a very steep descent. With a small amount like I mentioned, the plane descends a little faster and ignores the wind. I use it on several planes and have never had a problem. For example, I have it set on a Big Stick 40 and fly it on very windy days. The only planes I like to use flaps are on a high wing loading scale plane.