textproduct: San Joaquin Valley

KEY MESSAGES

1. A warming trend continues through much of the week.

2. Minor to Elevated Heat Risk across the area throughout the week.

3. Fire risk increasing Wednesday and again this weekend.

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

DISCUSSION

Quasi-zonal flow has returned today, allowing conditions to stabilize and allow ridging to build in. This will also allow for highs in the valley to be in the low to mid 90s today. Currently, the Probability of Exceedance (PoE) of reaching above 95 degrees today is 50 to 75 percent. The lower percentage is in the Northern portion of the CWA and increases Southward. For the Mojave Desert, the PoE 100 degrees is 60 to 80 percent. With that said, there is minor to elevated heat risk today. The warmest temperatures are still expected to hit on Friday, as the PoE 100 degrees for the entire Valley is at its highest. There is 15 to 50 percent chance of exceeding 100 degrees, again starting with the lowest percentages in the Northern portion of the CWA and the chances increasing as you go South. Take heat precautions for vulnerable populations and animals as we enter the summer time.

As we go into the weekend, an inside slider will move to the north. By Saturday, the PoE 95 degrees is 10 to 30 percent, with probabilities increasing the more South in the CWA you go. Sunday, there is a 15 to 45 PoE of 90 degrees, again the probabilities increasing as one heads South. However, the inside slider will also increase fire risk. Fuels remain dry, and the increased winds brought by the inside slider will bring concern to Eastern Tulare and Kern Counties. Minimum relative humidities will be between 15 and 20 percent this weekend within the Valley and 10 to 15 percent in the Mojave Desert.

Remember that while air temperatures are warm, water temperatures are still cold. Exercise cold water safety, as even the most experienced swimmers can lose dexterity due to cold water.

AVIATION

VFR conditions expected across the central California interior for the next 24 hours.

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

None.