I am planning on driving from Chiang Mai to Bangkok, on to Hua Hin and then Krabi. Having a difficult time find current major highway problems (flooding closures). Your knowledge of current conditions appreciated. Departure August 9. Return trip from Krabi about August 22. Driving my Honda CR-V.

You can find an app called "Highway Traffic" which shows real time camera on major roads in the country. I guess you will be using Route 1 which should be clear as its the major route better north and BKK.

I'd suggest entering your start and end points into Google Maps and see where it points you, with the live traffic data enabled.  It will also give you an estimate of the delays in each trouble spot.  And, unlike any advice from a static thread, the information will be up to date.