The new assistance includes sped-up livestock disaster assistance for California producers, provided under a newly signed farm bill, as well as targeted conservation assistance, watershed protection funds, additional summer feeding programs and emergency community water grants.
"Our goal here is to provide growers help and assistance," Agriculture Secretary Tom Vilsack told reporters.
By directing Agriculture Department staff to make the livestock assistance a "top priority," officials say they expect to provide California producers an estimated $100 million for 2014 losses and up to $50 million for losses in previous years.
The conservation assistance includes an estimated $5 million in new aid for California, and an additional $5 million in emergency watershed protection grants and $3 million in water grants for rural communities.
Interior Department officials are also being directed to operate federal water projects with "flexibility" to maximize water deliveries, and federal agencies are being directed to conserve more aggressively.
Much of the aid comes from existing federal programs, but is being provided with what administration officials describe as extra dispatch. This includes the intention to establish 600 additional summer feeding sites in the drought-affected region, under the Agriculture Department.
"The president definitely recognizes that the drought not only affects farmers, but also families," Vilsack said.
Accompanied by cabinet officials and top Democratic lawmakers, Obama is set to land in Fresno before being whisked off to a Valley farm for a first-hand look at the effects of drought. He will be announcing the aid as well as tying the severe drought to the consequences of man-made global climate change.
The president's visit comes on the heels of the Republican-controlled House passing, on a largely party line vote, a California water package that includes authorizing new dams and repealing a San Joaquin River restoration program. The Obama administration opposes the House bill.
"The problem in California is not that we don't have enough reservoirs," said Dr. John Holdren, White House science adviser. "It's that we don't have enough water in them. It wouldn't help to build any more (reservoirs.)"
A competing Senate bill has been introduced by Democratic Sens. Dianne Feinstein and Barbara Boxer. Feinstein has already met with the chief author of the House bill, freshman Rep. David Valadao, R-Calif., with both lawmakers voicing positive sentiments about the session.
Obama is scheduled to be accompanied at the Fresno-area event by Vilsack, Gov. Jerry Brown, Bureau of Reclamation Commissioner Michael Connor, Feinstein, Boxer and Rep. Jim Costa, D-Fresno.
No Republican lawmakers were included on the White House list of attendees.