Looking for white balance advise/tips

Out of curiosity, how are you guys/gals managing the WB at outdoor sporting venues where the light is constantly changing?

For instance, I was shooting a baseball doubleheader and I had the works when I came to the weather. I shot in everything from bright direct sunlight, light overcast, really dark rain/hail storm, clouds, then the evening with the weather pattern still going all over the place with the the venue lights switching on.

I started out with a grey card but it just isn't feasible to keep taking photos of the grey card every time the light changed.

Thanks for any tips you all may have, either in camera or in post.

The purists will say shoot in RAW and adjust for changing white balance in post.
If you are like me and shoot hundreds/thousands of images in a day and need to have them online sooner rather than later you may well choose to shoot in JPEG.
Now you have the problem that you highlighted in the original post. JPEG just doesn't allow you the same leeway for adjusting WB.

So what to do - I will interested to see if anyone has an easy solution to this.

Me? I took 1750 outside sporting images last Saturday taking in conditions from bright sun, cloud covered sky, rain and setting sun!!! From those I kept just over 700 images for uploading to my website on Sunday. RAW processing just takes too long in varying lighting conditions.
I spend between 20 - 40 secs post processing per image using an action (for my sports images)
Crop > noise reduction > check/adjust exposure > check/adjust shadows & highlights > check/adjust contrast > light sharpen ... adjust colour caste if I think I can fix in short time > flatten > save.

I set WB to auto and shoot away. Any images that have a distinct colour caste that I can't live with either ...
a) get a colour caste adjustment in Nik software (PS plugin)
b) get an adjustment in Photoshop's colour filter
c) accept the best colour caste I can achieve using these two methods
d) delete the photo

Try AWB for outdoor, and tweak in post if necessary.