textproduct: San Joaquin Valley

KEY MESSAGES

1. Elevated winds gusts expected for the San Joaquin Valley along with strong winds for the Mojave Desert Slopes through early Tuesday morning.

2. Minor Heat Risk across the lower elevations of central California through Tuesday with a warming trend and increasing risk starting Wednesday.

3. Widespread Moderate Heat Risk, including triple-digit heat, in the lower elevations Thursday until next weekend.

4. Practice safety around lakes, rivers, and streams, as water is still running cold.

DISCUSSION

A low pressure trough is currently tracking through central California, creating gusty conditions across the lower elevations of the Central Valley and in the lee side of the Tehachapi Mountain Range. There is a 70 to 80 percent chance for wind gusts to exceed 30 mph across the San Joaquin Valley this evening, and as such, a Wind Advisory has been issued that is valid through 2 AM PDT. Over the same time frame, there is an 80 to 90 percent chance for wind gusts to exceed 50 mph in the Mojave Slopes, leading to a Wind Advisory for this area through 5 AM PDT. Sustained winds 10 to 15 mph remain expected throughout Tuesday across the San Joaquin Valley due to the aforementioned trough being centered over the Great Basin region. Northwest flow on the upstream portion of the trough will continue to bring these stronger wind gusts, but an influx of moisture on Tuesday will raise relative humidity values across the area, reducing fire concerns; little precipitation is anticipated with this influx, with any amounts contained mainly to the higher elevations of the central Sierra.

As the trough tracks eastward on Wednesday, a warming and drying trend will set up over California. There is a 70 to 80 percent probability for afternoon highs to exceed 100 degrees across the San Joaquin Valley on Thursday, with an 80 to 90 percent probability for Friday and 70 to 80 percent again on Saturday. These warmer temperatures will drive down relative humidities across the region, with minRH values broadly less than 20 percent in the Central Valley and lower elevations of the Sierra Foothills Thursday through Monday; minRH values are expected at 10 percent or less across the Mojave Desert. These conditions expect to raise fire concerns again, especially for grass fires in these lower elevations.

AVIATION

VFR conditions expected across the central California interior for the next 24 hours. Surface wind gusts as high as 30 kts over the San Joaquin Valley through 09Z Thursday and up to 50 kts over the Mojave Desert slopes in eastern Kern County through 12Z Tuesday.

AIR QUALITY ISSUES

None.

CERTAINTY

The level of certainty for days 1 and 2 is high. The level of certainty for days 3 through 7 is medium.

Certainty levels include low...medium...and high. Please visit www.weather.gov/hnx/certainty.html for additional information and/or to provide feedback.

HNX WATCHES/WARNINGS/ADVISORIES

Wind Advisory until 5 AM PDT Tuesday for CAZ338. Wind Advisory until 2 AM PDT Tuesday for CAZ301>307-309>312- 314-315.