textproduct: San Joaquin Valley

KEY MESSAGES

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

2. Strong winds expected for the Mojave Desert Slopes through early Tuesday morning.

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 pair of troughs over the Pacific Northwest are helping to moderate temperatures over the area at the moment, keeping them near climatological normals for this time of year. This will keep high temperatures in the upper 80s and low 90s in the Valley today and tomorrow, providing pleasant conditions across the area. That being said, dry conditions will continue over the area today, with minimum relative humidities of 12-20% in the Valley and 10-12% in the Kern County Desert. This, combined with gusty winds, will create elevated fire concerns in eastern Kern and Tulare Counties. During the period of lowest humidities, winds are expected to gust to 30-35 mph in the Kern Mountains. Gusts will increase to 50-60 mph this evening and overnight. As such, a Wind Advisory is in effect for the Mojave Desert Slopes until 5 am Tuesday morning. Calmer winds and increased moisture will reduce fire risk Tuesday.

The second of the two troughs will move east rapidly on Wednesday. Once this happens, a high-amplitude ridge will build over the western half of the country, causing a rapid increase in temperatures. There is a 40-70% chance of most Valley areas exceeding 95 degrees on Wednesday, a 50-80% chance of exceeding 100 on Thursday, and a 50-90% chance of exceeding 100 on Friday. This will create increased heat risk across the area; please prepare for the hot weather now and check in on vulnerable people and animals. There will also be an increased fire risk later in the week.

AVIATION

VFR conditions expected across the central California interior for the next 24 hours. Surface wind gusts as high as 52 kts over the Mojave Desert slopes in eastern Kern County continue 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 high.

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.