textproduct: San Joaquin Valley

KEY MESSAGES

1. A warming trend will continue with afternoon temperatures approaching 20 to 25 degrees above average today through Saturday.

2. Daily and monthly record high maximum temperatures will continue to be challenged today.

3. Temperatures drop on Sunday but will remain above average through much of next week.

4. Practice cold water safety, as waterways will be running cold and fast over the next several days.

DISCUSSION

Another day of record highs will occur today after a mild morning with some locations reaching both record high minimum and maximum temperatures. There remains a 20-30 percent chance for highs to reach 95 degrees in the San Joaquin Valley today, so some monthly record high maxima would be reached. A better chance (50-60 percent) for highs at least 95 degrees is shown for the Kern County desert. There is a 10-15 percent chance for triple digits towards the Indian Wells Valley. Due to the warm weather, there is a slight risk for grass fires, mainly towards the Coastal Ranges and higher terrain adjacent to the west side of the San Joaquin Valley. In addition, as the ridge weakens and flow turns more zonal Saturday evening into Sunday, there is a chance for increased winds (20-30 percent chance of gusts at least 45 mph from Saturday evening into Sunday morning) over the typical prone areas of eastern Kern County, such as along the Mojave Desert slopes.

Highs Sunday through late next week will still be well above average, or around 10-15 degrees above average with widespread readings in the 80's in the San Joaquin Valley. However, the desert locations still have a moderate chance (45-55 percent probability) to reach 90 degrees for Sunday onward. The pattern becomes more zonal over Central California, though the axis of the ridge of high pressure shifts closer to the Four Corners region for Sunday and Monday. Models show the ridge rebuilding over California Tuesday through next week, so highs will warm back up slightly. No precipitation is forecast in the next several days.

AVIATION

VFR conditions are expected for the next 24 hours except for MVFR and local IFR due to fog/mist from 12Z-18Z Saturday in the San Joaquin Valley, including towards VIS and BFL.

FIRE WEATHER

Warm air temperatures and steady dew point temperatures will continue to result in lower minimum relative humidities, especially for the Mojave Desert, high Sierra, and Coastal Range. This will coincide with much lower 100- and 1000-hr dead fuel moistures and higher ERC in these areas. Rapid curing of fine fuels will bring about some risk for isolated grass fires. However, live fuel moisture remains below critical thresholds and significant wildfire potential remains at little or no risk.

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

None.