Frost/Freeze — W Central S.j. Valley, California

2018-02-21 · W Central S.j. Valley, California

Event narrative

Several locations reported minimum temperatures between 28 and 32 degrees.

Wider weather episode

A deep upper trough over the Great Basin provided for a cold northerly flow over central California for several days beginning on the afternoon of February 19. This resulted in a cold and dry airmass becoming settled over the San Joaquin Valley by the morning of February 20 as the valley experienced its coldest morning in several years at many locations as many reporting stations reported several hours of subfreezing temperatures. Since many trees and plants were already in bloom, numerous crops experienced significant damage from the cold overnight temperatures. The snap pea crop was nearly wiped out entirely and several nut orchards experienced significant crop damage as the almond crop was especially hit hard. Damage to citrus was somewhat migitated by the fact that much of the crop had already been harvested. The damage would have been significantly greater if not for frost protection measures taken by several growers.

Source: NOAA Storm Events Database, event_id 731503. Narrative written by the NWS forecast office that issued the report.