Forecasts of high winds – Red flag warning and wind warning in effect until Monday evening

October 14, 2018 – Winds blowing fresh gusts accompanied by a drop in humidity will worsen the weather problems of fires until Monday. Dry with high temperatures above normal until next weekend.

Discussion

Publicity

The latest satellite images show an upper ridge over the eastern Pacific and an upper trough descending south into the Great Basin. As the trough continues to dig to the south, a strong surface pressure gradient will develop, which, combined with air support at altitude, will cause windy conditions in the NorCal area within Monday. The MFR-SAC gradient is about 9 mbs this morning, with gusts of 15 to 30 mph reported mostly in southern Lake County, in the mountains of W Shasta County, in the northern Bag and north of the Sierra.

The strongest winds are expected along the western side of the Sacramento Valley, the foothills of the Sierra and parts of the Coast Mountains. A wind advisory is in effect for the west side of the valley today, as gusts of north wind could reach up to 45 mph.

Winds on the east side of the valley and south will be light but weak. In addition, 850 mb charts show a large area of ​​winds blowing along the foothills of the Sierra, with the general situational awareness tool indicating an abnormal component of the easterly winds.

As such, a wind advisory comes into effect for the Sierra Foothills from this morning to Monday morning, with the strongest winds becoming apparent at night. The combination of wind and reduced humidity will result in critical weather conditions for the fire.

A red flag warning is in effect for parts of NorCal's interior until Monday night. The winds will gradually weaken Monday night as the surface pressure gradient relaxes.

A lighter current to the north will continue Tuesday, but not as cool as this weekend. The general pattern does not change much as a ridge of high pressure remains in place, with dry conditions and above normal temperatures. The maximum forecasts will be 3 to 7 degrees above normal until mid-week. Look for highs of the valley in the 80s, 60s and 70s over the mountains.

In-depth discussion (Thursday to Sunday)

Strong pressure on the eastern Pacific is expected to spread to the west coast late this week, continuing the trend of dry weather with warm days and cool nights.