By Reginald Stanley. Posted January 21, 2020, 12:48 AM.

A Pacific trough introduced high clouds over Southern California throughout Monday, with precipitation finally reaching the region late Monday night. A significant plume of subtropical moisture also appeared to the south, mostly affecting northern Baja California and extreme southern San Diego County.

WeatherCurrents stations began recording rainfall just before midnight, and continuing as of this writing. The highest concentrations of rain at the moment appear to be over eastern Murrieta and French Valley. Since rain began falling just before midnight, WeatherCurrents' station in French Valley has recorded the most precipitation with 0.16 inches at the time of this writing, and 0.12 inches of that after midnight. Fallbrook was in second place with 0.12 inches total. Interestingly, nearby De Luz had not recorded any measurable precipitation. Doppler radar images have indicated the rain continuing into the early morning. While these showers were in the forecast, there was low confidence in this rain reaching the ground due to a relatively dry lower atmosphere prior to the storm. Most precipitation seen on Doppler radar images earlier Monday was only virga - evaporating before reaching the ground. The trough is expected to move east Tuesday morning, ending rain chances as offshore flow re-establishes itself in the region later this week.