June 5, 2019 – Much above normal temperatures today then cooling into the weekend. Breezy northerly winds this weekend could bring fire weather concerns across portions of the Valley and adjacent foothills.
High pressure will continue bringing much above normal high temperatures this afternoon. Readings will push to near 100 degrees at many locations, which is 10 to 15 degrees above normal for early June. This will lead to moderate heat risk for sensitive groups during peak heating hours this afternoon.
Increasing westerly flow with trough dropping south along the west coast will push instability and thunderstorm chances east of the area Wednesday and beyond with dry conditions prevailing.
Developing onshore flow will bring gusty southwest winds and much cooler temperatures late Thursday into Friday over the srn Sacramento and San Joaquin Valleys. Highs will fall back into the 80’s and may struggle to warm out of the 70’s Friday. Gusty North winds will then develop Friday afternoon into Saturday, as the trough pushes east into the Great Basin Region.
Breezy to gusty northerly winds this weekend will bring potential fire weather concerns across portions of the Sacramento Valley and adjacent foothills. The surface pressure gradient will increase as upper level ridging develops to the north. The gradient and 925 mb winds suggest gusts in the 25 to 35 mph range could be possible, mainly on the west side of the Sacramento Valley. Humidity levels Saturday and Sunday afternoon could reach the teens in the Sacramento Valley. Grasses and other fine fuels will see accelerated curing from the high temperatures and low humidity and should become more susceptible to burning. Shrubs, trees, and heavier fuels will be slower to lose moisture, especially in higher terrain, where conditions have been wet and new growth continues.
Extended Discussion (Sunday through Wednesday)
Dry weather is expected for the weekend into early next week. Main issues this weekend are rising temperatures and increasing northerly winds, especially on the west side of the Sacramento Valley Saturday and Saturday night as high pressure ridging builds. See Fire Weather Discussion for more information of fire weather concerns.
Valley high temperatures in the mid 80’s on Saturday, rising into the 90’s Sunday. Monday forecast temperatures rise into the mid to upper 90’s, with the upper Sacramento Valley reaching triple digits on Tuesday.