Dry western air starts a little bit west of the Balcones Escarpment, which Austin is at the foothills of.
Austin is noticeably less humid than Houston. But it’s nothing like the dryness of California. It actually has the same annual precipitation as Seattle (just in a few big storms, rather than a constant drizzle).
Austin is not “Western, desert, dryer air”. It’s usually 60-70% relative humidity. (https://www.weather-us.com/en/texas-usa/austin-climate) While those are basically the same relative humidity numbers as Berkeley (https://www.weather-us.com/en/california-usa/berkeley-climate), in the summer it reaches that level of humidity while temperatures are in the 90s or 100s.
Dry western air starts a little bit west of the Balcones Escarpment, which Austin is at the foothills of.
Austin is noticeably less humid than Houston. But it’s nothing like the dryness of California. It actually has the same annual precipitation as Seattle (just in a few big storms, rather than a constant drizzle).