Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
236 FXUS66 KHNX 162110 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 210 PM PDT Sun Jun 16 2024 .KEY MESSAGES... 1. A Red Flag Warning has been issued for strong winds coupled with low relative humidity that will bring Elevated Fire Weather concerns to the Kern County mountains, West Hills, Kern Desert and the San Joaquin Valley through Tuesday Morning. 2. A cooling trend will bring temperatures closer to seasonal average for today. Monday temperatures will be around 3 to 5 degrees below normal. 3. Strong to damaging wind gusts will develop along the Mojave Desert Slopes each afternoon and overnight through Monday night. Afternoon and evening breezes will develop across the San Joaquin Valley with locally gusty conditions near the passes of the West Side Mountains through Monday. 4. Snowmelt from the higher elevations of the Sierra Nevada, will continue to result in dangerously cold and fast flows along rivers and waterways. 5. Starting Tuesday a warming trend will begin with triple digits anticipated starting Friday lasting through next weekend. && .DISCUSSION... Sunny, warm and windy across Central California as the atmosphere continues to dry. These conditions were the results of a dry cold front cross the area late Friday. This cold front started the cooling trend in temperatures and breezy condition which will now be re-enforced by a second disturbance dropping from the Pacific Northwest. While temperatures will fall below normal values going into Monday, winds will become much stronger. High-Res Short-range ensembles wind analysis has a 30-60 percent chance of having wind speeds reach 30 mph across the region. As a result, Central California is now more susceptible to grassland and dry wood fires. Peak cooling and strong winds will occur on Monday, followed by a slow warming trend for much of the week that has a 30-50 percent chance of reaching heat-wave categories by next weekend. High-Res Short-Range Ensemble mean temperature and wind analysis show the continuation of cooler air surging into Central California. Ensemble Mean Max Temperature analysis for Monday has less then 15 percent Probability of Exceedance (PoE) of having the San Joaquin Valley temperatures break 90. This increases confidence that the cooling temperatures will bottom on Monday and go below normal. At the same time, the cooler air and upper level winds will support very strong winds tonight and Monday. While a 30 to 60 percent chance of widespread 35 mph gusts will exist, local gusts in Kern County reach percentages of 70 to 90 percent PoE. Over the same area, PoE of over 55 mph only drops to 50 percent. Therefore, a very windy night ahead. By Tuesday, the disturbance slowly pushes out as temperatures start a rebound and winds diminish. While the threat of elevated fire danger lowers, humidity across the region remains low as ensemble mean values only recover into the lower 30 percent RH. Yet, ensemble mean upper-air pattern does not suggest an significant warm-up until later in the week. Longer-range ensemble upper-air analysis maintains a cooler temperature solution for much of the period before changes gears next Friday. Yet, confidence the next Heat-Wave is low as Ensemble Cluster Analysis does not hint toward a strong ridge solution. Current PoE of reaching 105 degrees on Friday remains mostly below 10 percent. While PoE of reach 100 degree may rise to 20% to 40%, the pattern is not set-up for a good heat-wave. By the weekend, the pattern looks a bit more favorable for a ridge pattern as Ensemble Cluster Analysis shows a up-tick toward heat-wave category. Latest PoE shows a 30 to 50 percent chance of reaching 105 degrees. On Sunday, those percentages remain the same as medium confidence continue toward another heat-wave. && .AVIATION... VFR conditions will prevail across the Central CA interior for the next 24 hours. Local reductions of visibility near fires and along the Mojave Slopes in the Kern County Desert. && .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 5 AM PDT Tuesday for CAZ338. Red Flag Warning until 8 AM PDT Tuesday for CAZ579-596-597. && $$ Operational......Molina Support/IDSS.....SM weather.gov/hanford