Summer weather in the southwestern section of the United States is influenced by a subtrop...

Summer weather in the southwestern section of the United States is influenced by a subtropical high-pressure cell, yet Fig. (p. 270) shows an area of low pressure at the surface. Explain.

FIGURE Average sea-level pressure distribution and surface wind-flow patterns for January (a) and for July (b). The solid red line represents the position of the ITCZ.