Area Forecast Discussion
Issued by NWS Eureka, CA
Issued by NWS Eureka, CA
430 FXUS66 KEKA 051310 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 610 AM PDT Fri Jul 5 2024 .SYNOPSIS...The long-duration extreme, record breaking heat wave will continue. The strong dome of high pressure will begin to center over N CA, further increasing temperatures Saturday. Sunday temperatures will ease by a few degrees, but remain very hot into the first half of next week. The heat risk will also be accompanied by very dry air and breezy afternoon winds increasing fire weather concerns. && .DISCUSSION...High pressure and weak offshore flow will bring another sunny day with hot weather. Most areas will see a few degrees of warming over yesterday. This morning many of the valleys have cooled to around 60 degrees, however the ridges have stayed much warmer, only dropping to around 80 degrees. Tonight is expected to be similar with the valleys seeing better cooling and the ridges staying very warm. Saturday is expected to be the hottest day with many areas over 110 and even some approaching 115. On Saturday the probability of exceeding 110 is over 60 percent in many of the lower elevation interior valleys. Saturday the winds get fairly light aloft. Sometimes this scenario will compress the marine and allow temperatures to warm to around 80 at the coast. At this point this looks unlikely, but it is possible. Sunday and into next week north to northwest winds are expected to increase again. This may bring a return of the marine layer, but it looks like it will at least bring some cooler temperatures to the near coastal areas. The ensemble spread grows in the strip that includes most of Del Norte county, Humboldt county and western Mendocino county. Areas farther inland will likely see slightly cooler temperatures, but only a few degrees. Early next week some of the models are showing a weak upper level low approaching the coast. This would bring the potential for thunderstorms. The 06Z GFS shows this pattern, however it doesn`t show up in any of the ensemble clusters so will just monitor it. MKK && .AVIATION...Light winds and a low level inversion have already had a slight affect on flight categories this morning at the coastal terminals. Dry air aloft and subsidence will help clear things out with haze lingering at the northern terminals as smoke from wildfires gets trapped under the inversion. Light winds are expected through the TAF period with mostly MVFR/VFR categories prevailing aside from the aforementioned haze from wildfire smoke. MOS guidance is flagging a drop in flight categories to IFR/LIFR later tonight and into Saturday for KCEC and KACV. VFR categories for KUKI prevail with late afternoon gusty northerlies expected for a short period. /EYS && .MARINE...Fair seas and calm winds prevail for all area waters for the next 36 hours or so. Northwesterly winds start to build Saturday night with seas responding by Sunday morning in the northern outer waters as wind waves with square profiles develop. Small craft advisory conditions will begin in the northern outer waters Sunday morning with the previously mentioned square wind waves which will expand into the southern outer waters by Sunday afternoon. /EYS && .FIRE WEATHER...Hot temperatures continue and are expected to bring RH down to 5 to 15 percent this afternoon. The typical diurnal afternoon winds will be slightly enhanced by the hot temperatures and this will increase fire weather conditions. Tonight the valleys are expected to decouple again and see recoveries of 40 to 50 percent. The thermal belts are expected to see temperatures only drop to around 80 with RH recoveries around 20 to 30 percent. This will increase fire danger slightly. Saturday afternoon northwest winds will increase again, especially in southern Lake county. The red flag warning looks on track in southern Lake county. Farther north in Trinity county the RH will be low as well and there is expected to be breezy afternoon winds as well. The duration may not be long enough to warrant a red flag warning so have left the fire weather watch in place. Sunday as the upper level ridge starts to push east areas closer to the coast are expected to start seeing a slight marine push. Winds are expected to weaken in Lake county, but may remain elevated in Trinity county. Monday there is still the potential for some showers and thunderstorms in the afternoon. This will need to be watched as it gets closer. For now the chance looks less than ten percent. MKK && .EKA WATCHES/WARNINGS/ADVISORIES... CA... Heat Advisory until 8 PM PDT Monday for CAZ102-112. Heat Advisory until 9 AM PDT this morning for CAZ104-106. Heat Advisory from 10 AM this morning to 11 PM PDT Saturday for CAZ104. Excessive Heat Warning until 7 PM PDT Monday for CAZ105-107- 108. Excessive Heat Warning from 10 AM this morning to 8 PM PDT Saturday for CAZ106. Fire Weather Watch from Saturday afternoon through Sunday evening for CAZ283. Excessive Heat Warning until 8 PM PDT Monday for CAZ110-111- 113>115. Red Flag Warning from 3 PM this afternoon to 11 PM PDT Saturday for CAZ264. NORTHWEST CALIFORNIA COASTAL WATERS... None. && $$ Visit us at https://www.weather.gov/eureka Follow us on Facebook and Twitter at: https://www.facebook.com/NWSEureka https://www.twitter.com/NWSEureka For forecast zone information see the forecast zone map online: https://www.weather.gov/images/eka/zonemap.png