March 5, 2018 – Dry and milder weather through mid-week, then precipitation chances return for the second half of the week.
Discussion
Mainly clear skies across interior NorCal early this morning. Current temperatures are colder across most of the region compared to 24 hours ago and generally range from the single digits in the mountain valleys to mid 30s to lower 40s in the Central Valley.
Last week’s system continues to shift east with short-wave ridging expected to result in dry weather with milder daytime temperatures for the region through mid-week.
The next upstream system is presently well off the coast (west of 140W) and is forecast to move little over the next 48 hours. It may send some high clouds our way from time to time the next couple of days. Forecast models indicate that the low will lift out toward the PacNW on Wednesday with a trailing cold front spreading precipitation southward into interior NorCal by Wednesday night and Thursday along with gusty southerly winds. The front is expected to weaken considerably as it moves southward.
This system is expected to be milder and with less QPF, so impacts are expected to be much less than late last week.
Extended discussion (Friday through Monday)
A series of disturbances will bring periods of precipitation throughout the extended period.
A weak disturbance moves through Friday with mainly mountain precipitation. Rainfall amounts are expected to be fairly light in the Valley, with maybe an inch or two of snow in the mountains above 6000 feet. Another similar system continues precipitation into Saturday, with snow levels dropping to around 5000 feet and additional light snow accumulation.
The ECMWF and GFS models are hinting at a wetter system sometime from Sunday morning into Monday, though confidence isn’t high this far out. Snow levels look to be around 5500-6500 feet. Will have to watch this system to see how it develops.