March 30, 2018 – Dry and warm this week. Potential for wetter weather late next week.
High pressure remains in control with above normal temperatures and plenty of sunshine today. Afternoon temperatures will top out in the low 80s in the valley with 50s to 60s over the mountains. Upper ridge begins to flatten Saturday as shortwave attempts to break through the ridge. Limited moisture so not expecting anything in the way of precipitation but it will serve to slightly cool temperatures for Saturday and Sunday. Locally breezy southerly flow will develop by Sunday. Temperatures cool a few more degrees on Monday as broad troughing sets up over NorCal.
Extended discussion (Tuesday through Friday)
Upper level ridge is expected to weaken as an embedded shortwave trough in the main flow moves across northern California sometime between Tuesday evening and Wednesday morning. This little disturbance will bring a chance for a quick shot of rain across the Cascades and the northern Sierra Tuesday and Wednesday.
Confidence is increasing for a return to a widespread wet pattern for northern California towards the end of next week and into next weekend. Latest model runs show a moisture stream impacting the west coast and will result in light to moderate rain for Thursday and beyond. Early projections indicate snow levels will be well above pass levels, so the threat for heavy snow looks minimal at this time.
Afternoon high temperatures across the forecast area Tuesday and Wednesday will remain somewhere between 5 and 10 degrees above average for early April, but expect temperatures to drop closer to average under a slightly cooler air mass towards the end of next week.