• Precipitation accumulations of 1–2 inches from a separate system have primed conditions in southern CA and may combine with precipitation from the expected event to cause the San Diego River to briefly rise above monitor stage
• Freezing levels are forecast to be 4,000–5,000 over southern CA, which could lead to freezing precipitation over higher elevations

System to Bring Precipitation to CA

• A system is expected to bring precipitation accumulations of 1–3 inches to most of California
• While this event is forecast to have characteristics of an AR (IVT >250 kg/m/s), it does not have the spatial structure of an AR (long and narrow)

Click IVT or IWV image to see loop of 0-60 hour GFS forecast (Valid 1200 UTC 22 Dec – 0000 UTC 25 Dec)