Heavy Rain — San Mateo, California

2022-12-31 · near Redwood City, San Mateo, California

Event narrative

Redwood City with 4.47.

12/31/2022 was the 3rd wettest in a record that goes back to 1906. The daily rainfall made up 42.8% of December 2022's rainfall.

The wettest day on record at Redwood City was back on 10/13/1962 with 4.88 inches.

Wider weather episode

An atmospheric river impacted the Bay Area on December 31st, resulting in significant rainfall across the San Francisco Bay Area. Initial forecasts called for the most intense rainband to progressively move south towards the Central Coast as the day went on. However, the morning of the 31st, a surface low developed west of San Francisco, and the river stalled over the Bay Area. This resulted in significant rainfall totals for many Bay Area sites. Most notably, downtown San Francisco received 5.46 inches of rain on the 31st, the second wettest day on record. The Oakland Museum received its wettest day since records began in 1970, with 4.75 inches of rain.

View location on OpenStreetMap → (37.4800, -122.2700)

Source: NOAA Storm Events Database, event_id 1079729. Narrative written by the NWS forecast office that issued the report.