At summer solstice, what is the solar altitude at Hayward, CA given Hayward's latitude of 37 degrees N?

At summer solitice, CA given Hayward's latitude of 37 degrees N is 37 degree + 23 degree = 60 degree.

Explanation:

The sun rises at 43 degree altitude in summer. At Summer solstice the sun travels longest path through the sky and that day has the most daylight.

When the northern hemisphere is tilted towards sun, the sunlight falls at steeper angle and causes the hot months of summer.

The Hayward's latitude of 37 degrees is 60 degree north.