WASHINGTON — D.C. area travelers can fly nonstop to San Francisco from all three local airports, but there are no direct flights to San Jose, the heart of Silicon Valley.

That will change this fall.

Southwest Airlines will start nonstop flights to San Jose from BWI Marshall Airport on Nov. 6. Southwest is betting on demand from the region’s big technology community for the direct service to San Jose.

Southwest also recently announced nonstop service from BWI Marshall to Sacramento starting in August.

Low-cost carrier Allegiant has also started flights this week from BWI Marshall to Asheville, North Carolina; Tulsa, Oklahoma, and Knoxville, Tennessee. Allegiant is offering introductory fares on those flights for as little as $39 each way.

BWI Marshall remains the Washington region’s busiest airport, with a record 23.8 million passengers last year.

Through February, the airport has posted eight straight monthly passenger records.