Hello there Linda,
Welcome to planDisney and thank you so much for your question! Your trip to the Happiest Place on Earth will be here in just a few short weeks - how exciting!
While the Happiest Place on Earth is still just that even during heavy rain, there have been instances even in the past few days where the Disneyland Park has closed earlier in the evening due to significant weather - though this is definitely not the norm.
For the vast majority of inclement weather conditions, most attractions and indoor shows continue to operate and there is still plenty to do! You can see a helpful list of potential attractions that may temporarily close during more severe weather on the
Weather FAQ page.
I would just recommend keeping an eye on the weather forecasts, in the
Disneyland Resort mobile app, and Cast Member directions while visiting. Also, the two items that have made the biggest difference for me when I've visited when it rained are water-resistant/proof shoes and a good rain poncho! Wet feet can be pretty annoying so I'd even suggest bringing an extra pair of socks in case you need it.
There is still plenty of fun to be had even when it's raining at the Happiest Place on Earth, so I hope you have a great visit. Thanks again for your question, Linda!
Have a Magical Day,
Greg