November 17, 2019 – Dry and mild conditions through early next week. Very warm today and Monday with record highs possible in the northern Sacramento Valley. Pattern change still on track around mid week with breezy winds, cooler temperatures and possible rain/snow mainly in the Sierra Nevada.
Discussion
As high pressure continues to build in, clear skies and light winds are seen across the majority of NorCal interior. Patchy fog is expected again this morning in the Sac Valley and Delta region, dissipating by late morning. Much warmer than normal temperatures will be seen today and tomorrow, with some locations possibly breaking high temperature records. Generally, Valley highs through Monday will range from 75 to 85 degrees, with highs in the mountains in the 50s to low 60s.
A low pressure system moves into the PacNW late Monday with the associated trough deepening and moving across NorCal Tuesday into Wednesday. Temperatures cool off with this mid-week system, although highs still stay about 5 to 8 degrees above average for mid- November. The main focus of this system will be the possible precipitation and breezy north winds.
North winds will increase in the northern Sac Valley late Tuesday, with the strongest winds Wednesday and Wednesday night. Peak gusts around 30-40 mph may be seen in the Valley. Some small chances for rain/snow are seen beginning late Tuesday night and continuing through late Wednesday night in the Sierra Nevada. Snow levels look to be around 6kft and a few inches may be possible at pass level. It is worth noting that as the low closes off, models tend to diverge in solutions for winds and precipitation so keep up to date with the forecast.
Extended Discussion (Thursday through Sunday)
North to northeast flow will increase by mid week as an upper level disturbance drops southward over CA. Gusty winds are possible into early Thursday, with gusts in the 20 to 30 mph range. Lighter winds are expected Thursday afternoon as the Nly pressure gradient relaxes. The upper level low will gradually shift eastward late in the week, ending precipitation threat. Regarding temperatures, daytime highs will be above average through the period, with Valley highs in the mid 60s to low 70s.