Humidity creep

I’d like my rh to be under 50%. Other than getting a dedicated dehumidifier, how do I best utilize my hvac to lower humidity?

I changed thermostats and the new one tracks humidity (ecobee). This winter I had very low humidity, and this summer I’ve had a few high humidity (60%) alerts. I’ve been able to get the humidity down to 50% by running the ac. but in evening I see both humidity and temp creep up (1% an hour) (I would have expected rising temp and a closed house to have dropping rel. humidity). I also don’t see humidity creep during the day.

The outside humidity is 80% and raises to near 100% at night as the temps drop.

I checked my water meter, and there is no flow, so I don’t think there are leaks .

(I have a newer house, so it should be well sealed, and a fresh air fan that is on a timer to run a few hours a day) I checked that the condensate pipe drains to the outside.

I’m thinking set the temp cooler at night, to pull h2o out at night, (and also move timer to flush air at night) Not having the fan run “extra”. (More efficient cooling to continue blowing air over the cold coils until they reach ambient temp, but also evaporating water that had condensed but not yet drained)