March 12, 2019 – A weak storm moves through today bringing light precipitation to portions of the forecast area. Dry weather follows into early next week with some breezy north to east wind late Today into Wednesday. Next chance of precipitation next Tuesday.
Satellite imagery shows some high cloud cover spreading over the north state this morning ahead of a weak cold frontal band now pushing in towards the north coast. This weak frontal band is forecast to drop southeastward across the forecast area today but measurable precipitation is unlikely at the lower elevations. Orographics of the mountains will be needed to get even light precipitation out of this system. Current forecasts keep snow amounts at under an inch today so impacts to travel will be minimal. Daytime cloud cover and cooler airmass will bring cooler daytime highs today down to a little below normal. Upper low associated with the weak front will shift quickly into the Great Basin this afternoon and tonight so by Wednesday morning precipitation threat over the Sierra will end.
Upper level northerly flow combines with a northerly surface gradient to bring breezy north winds late today through Wednesday. Models still indicating winds to remain a little below advisory criteria. Upper ridge axis shifts over the west coast early Thursday with reduced gradients at all levels bringing lighter winds. GFS/ECMWF slide a weak trough across the state late Thursday. Any precipitation with this system is unlikely but cloud cover will keep daytime highs a little below normal. Stronger upper ridging on Friday will bring the beginning of a significant warming trend going through the coming weekend with max daytime temperatures jumping to above normal.
Extended Discussion (Saturday through Tuesday)
Mid-level ridging overspreads the west coast Friday night and continues to amplify through early next week. Dry weather and warming temperatures will be seen as 850 temperatures increase roughly 4 degrees between Saturday and Monday. Temperatures in the northern San Joaquin and southern Sacramento Valley may reach into the 70s Saturday, with temperatures over 70 degrees expected in all of the Valley by Monday. The ridge may get undercut by a system Tuesday and precipitation chances return to NorCal.