NO! Well I don't really have experience of either in December, to be perfectly honest but when we were in Morocco in April we didn't get much sunshine. In fact I've read that whatever time of year you go to Agadir you get a lot of cloud and mist because of it's position. Maybe Marakesh is better

Wow, mabe I got lucky! I went from 15th March until the 25th March and it was glorious most days in Agadir, far more than expected. Its misty in the morning but very warm come 10am. Im not sure about December though? Which was the original question, which doesnt really help you eh?

The average temp. for Gran Canaria in December is around 21°, slightly higher than Marrakech. I haven't been to Agadir if that's where you are thinking of going. I visited Marrakech in late November and the weather was very warm during the day but it cooled down a lot at night.
I have stayed in Gran Canaria again late November and the weather was around 24°, somewhat higher than average but on one visit to Tenerife in early December the weather was quite cool.
The weather is all a bit hit and miss for any of the atlantic resorts in December but I think you may get better weather in the canaries.

Judith

Either Joeyc got lucky or we were very unlucky. We'd heard the same - that the sun would come through the clouds nice and warm from about 10am. Well on the first day we thought we'd brave the sunloungers and wait. !0am came and then we said it'll be out by 11 now we waited and we waited and it went on like this for most of the week

It wasn't all doom and gloom because when we did see the sun (for a few hours on a couple of days) it was hot! It just wasn't what we were led to believe. On our return, we read here on HT from a fellow member that the weather is often as we had it (bits of sunshine through the mist) in Agadir and that if you want guaranteed sunshine to look elsewhere.

On the coast they will be the same (the islands are all coast) but Marrakeshwill be warmer and dryer

I think the Canaries can be relied on for sunny weather more than Agadir.
I know them both well