000 FXUS66 KHNX 282112 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 212 PM PDT Thu Mar 28 2024 && .KEY MESSAGES... 1. A Wind Advisory will be in effect from 11 AM Thursday through 1 AM Friday for the Mojave Slopes and the Kern County Desert with wind gusts up to 50 mph. 2. A Wind Advisory is in effect along the West Side Hills from 3 PM Friday through 6 AM Saturday with wind gusts up to 50 mph. 3. There is a 50-70% chance of Major Winter Storm impacts in the Sierra Nevada this weekend. 4. A Winter Storm Warning is now in effect for the Sierra Nevada from 11 AM Friday through 5 PM Sunday. Badger Pass and Wishon Lake have a 90% chance of at least 18 inches of new snow with this event. 5. A Winter Storm Watch is in effect for the Kern County Mountains above 5,000 feet from 4 PM Friday through 5 PM Sunday. Pine Mountain Club has a 34% chance of at least 6 inches of new snow with this event. && .DISCUSSION... Light precipitation continues to exit the forecast area this afternoon associated with a shortwave aloft. As the disturbance exits the region, gradients across the Kern County Mountains will tighten, leading to an increase of winds through and below the mountain passes of Kern County. This shortwave disturbance stems from a upper low that is currently based in the Pacific Northwest. The system in the Pacific Northwest will dig to the south to southeast overnight tonight and approach Central California by tomorrow afternoon. This system is forecast to bring appreciable precipitation to the San Joaquin Valley and Sierra Nevada starting Friday with snow levels around 5,000 feet. Valley rain and Sierra Nevada snow is forecast to intensify in the afternoon and evening hours on Friday, with the associated cold front bringing the most intense precipitation on early Saturday morning. Precipitation is forecast to continue through Saturday night and Sunday morning. Locations such as Badger Pass and Wishon Lake have about a 90% chance of seeing at least 18 inches of new snow with this event through Sunday afternoon. Grant Grove and Huntington Lake also have high probabilities (75-80% chance) of seeing at least 18 inches of new snow through Sunday afternoon. With the holiday weekend seeing increased travel, potential for impacts increase as well. The Probabilistic WSSI is showing a 50 to 70% of Major Winter Storm impacts on Saturday. We have gone ahead and issued a Winter Storm Warming from 11 AM PDT Friday lasting through 5 PM PDT Sunday for this event. Southward in the forecast area, winter storm impacts are projected in the Tehachapi Mountains and Pine Mountain Club at elevations above 5,000 feet. Several inches of snowfall over the weekend make the commute more difficult on Saturday. From a probabilistic perspective, there is a 34% chance of at least 6" of snow at Pine Mountain Club associated with this storm through Sunday afternoon. A Winter Storm Watch will be in effect from 4 PM Friday through 5 PM Sunday. Below the snow line in Kern County, there is a Marginal Risk of Excessive Rainfall, mostly impacting the mountains and passes. Localized flooding cannot be ruled out in the event of a heavier band of showers overnight Friday and early Saturday morning. Another potential threat to the forecast area will be thunderstorms in the San Joaquin Valley on Saturday afternoon. Once the front passes through the valley on Saturday morning, the cold pool aloft coupled with any breaks in cloud cover has the potential create an environment with enough instability to support thunderstorms. Brief heavy rain and small hail are the most likely hazards associated with afternoon convection, if it materializes on Saturday afternoon. Regardless, this system will produce an appreciable amount of rain across the SJ Valley. Here are the latest NBM probabilities for select locations across the San Joaquin Valley to see at least one quarter of an inch of rain from 5 PM Friday through 5 PM Saturday: Merced: 71% Madera: 66% Fresno: 71% Visalia: 66% Bakersfield: 68% The upper low is projected to exit the region Sunday night. As we head into next week, ensemble guidance shows a ridge of high pressure building over the west coast, including California. This pattern will lead to drier and warmer conditions across the CWA. Blended model guidance takes highs to near 80*F next Wednesday across most of the San Joaquin Valley. && .AVIATION... VFR conditions will prevail across Central California for at least the next 24 hours. && .AIR QUALITY ISSUES... ISSUED: 03/27/2024 14:26 EXPIRES: 03/28/2024 23:59 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 1 AM PDT Friday for CAZ337>339. Wind Advisory from 3 PM Friday to 6 AM PDT Saturday for CAZ300- 308-313. Winter Storm Warning from 11 AM Friday to 5 PM PDT Sunday for CAZ323-326>331. Winter Storm Watch above 5000 feet from Friday afternoon through Sunday afternoon for CAZ333-334-336. && $$ ab weather.gov/hanford