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Fire weather continues to be the main concern throughout the West, although AZ has been continuing to have severe storms and flash flooding. Numerous afternoon and terrain-generated storms have popped up nearly every day for the past two weeks over much of the interior West, and have contributed to fire spread/ignition. New fires in CA have expanded the geographical region affected by major wildfires. After cooling and moistening the last 24 hours, a dramatic warm-up and drying trend over the next 48 hours will undoubtedly make the fire situation worse. The really interesting stuff comes towards the end of the week. The models have been all over the place with a developing blocking high pressure area that is forecast to be centered 800 mi W of WA by day 5. One of two possible scenarios will likely occur. 1. A trough/closed low swings SE over WA and OR, bringing cooler but very windy and convective weather over much of the interior. This would bring extreme fire danger ahead of the front in the NW, but substantially decrease after the front moves through as a result of cooler temps and possible precip. CA would see cooler temps but no rain and very strong winds, so an extreme fire scenario would develop. 2. An even deeper closed low develops and retrogrades SW off the OR/CA coasts, bringing showery/thundery weather to much of the West (including coastal areas). This could bring season-ending rains to some areas, and rare fall showers in CA. Fire danger could decrease substantially if this scenario pans out. Climatology would favor the drier/windier scenario, but the GFS is insisting on a wetter one. We’ll see what happens, as this is less than 7 days out.