Fresno, in California’s agriculturally vital Central Valley, receives around 300 mm (about 12 inches) of rain a year, concentrated almost entirely in the winter months with a long, hot, completely dry summer. Because the surrounding valley is so flat and rain so infrequent, sustained winter storms, particularly atmospheric river events, can cause significant flooding of agricultural land and low-lying areas that see almost no water the rest of the year. The nearby Sierra Nevada foothills can also intensify rainfall as storms move eastward across the valley. Because a typical summer week here involves no rain at all, radar is most useful during the concentrated winter storm season. NWS Doppler radar KHNX (Hanford) covers the region.
Learn more: How Does Rain Radar Work? · Open the full Rain Map