Skies are clear early this morning other than a few high clouds and an area of stratus developing over the Sacramento region. Current temperatures range from the mid to upper 30s in the mountain valleys to the 50s to lower 60s across the Central Valley and foothills.
The upper level ridge centered offshore the Pacific Northwest will continue to strengthen today limiting any shower development. By Thursday and Friday, ensemble and latest operational runs continue to indicate a retrograding trough pushing into central California from the Great Basin/Rockies. There is some uncertainty on the track of the low, but it is expected to produce enough moisture and instability to support potential for showers and thunderstorms in the mountains and Central Valley, mainly to the south of I-80.
Warming trend accelerates today with high temperatures forecast to rise another 5 to 10 degrees compared to Tuesday. Daytime temperatures will then remain around 5-15 degrees above average heading into the weekend.
Extended Discussion (Sunday through Wednesday)
An upper level low will move towards the desert southwest while a high builds to our north. Dry and warm conditions are forecast for the Valley while diurnally forced showers and thunderstorms remain possible for our ridges. Convective parameters support isolated to scattered thunderstorms along the Sierra and primarily south of I-80. The Cascades could see some development too; however, confidence is not nearly as high for our northern most ridges.
Looking into next week, ridging and the trough continue to move eastward while a long wave trough develops over the Pacific. This could bring scattered showers and thunderstorms to the region, but it is still too early to pinpoint timing and location.