textproduct: San Joaquin Valley

KEY MESSAGES

1. Damaging winds and hazardous travel conditions continue in eastern Kern County through Noon Today.

2. The risk for fire starts increases Friday into the weekend due to lowering humidity and a warming trend.

3. Another chance for unsettled weather as precipitation, winds and lightning wil exist by the middle of next week.

DISCUSSION

The passage of a disturbance through the region earlier this week resulted in cooler temperatures and strong winds across Central California. As the disturbance exits the region, winds have and will continue to diminish going into the weekend. In addition, temperatures will bottom out today and start a warming trend this weekend. Yet, until we are able to scour out the cold air-mass across Central California, will expect the Probability of Exceedance of reaching 90 degrees to remain below 30 percent (except for areas near Taft on Sunday) as the high pressure ridge will not have enough time to develop another heat-wave. Therefore, temperatures will peak into the mid to upper 80s during the period.

Another disturbance is progged to enter the region next week behind a weak disturbance that will help break-down this weekend ridge pattern. Ahead of the disturbance, temperatures will begin cooling on Monday and an uptick in winds over the favored locations of the Sierra Nevada Crest and the Tehachapi Range/Mojave Desert. Ensembles place the onset of precipitation from the next storm between Tuesday Night and early Wednesday Morning. Will favor the latter solution of early Wednesday. Probability of receiving a wetting rain (0.10) reaches 30-40 percent near Yosemite on Wednesday afternoon and continues into Wednesday night.

By Thursday, while ensemble uncertainty in the storms placement is high, probability of receiving a tenth of an inch (0.10) jumps to 50-70 percent across the Sierra and up to near 35 percent across the San Joaquin Valley. In addition, probability of receiving a Half of an inch (0.50) across the High Sierra during a 24 hour period remains around 30-40 percent, and the probability of receiving a quarter of an inch rises to near 50 percent. With snow levels remaining above 7,000 feet, the mentioned percentage ranges will place snow accumulation in the 3 to 5 inch category with a 10 percent chance of 8 inches near Glacier Point where orographics may enhance precipitation values near the half inch mark. Uncertainty in the timing of the storms passage will necessitate a mention of precipitation until early next Saturday. Furthermore, if the storm takes a later timing, will expect Thunderstorm activity for the latter part of the week as ensembles place a 20-30 percent chance of thunderstorms from Merced/Yosemite down to just north of Kern County on Thursday during the potential passage disturbances axis over Central California.

Latest CPC outlooks suggest near average to a slight tilt in the odds towards above average precipitation for the 6-10 day period and 8-14 day periods. Above average temperatures continue trending toward the 40-50 percent chance of leaning above seasonal normals.

AVIATION

VFR conditions will prevail across central California for the next 24 hours. Easterly surface winds ranging from 20-30kts expected across the Tehachapi Range and Mojave Desert Slopes through 06Z Saturday.

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

High Wind Warning until noon PDT today for CAZ338.