Air quality levels are continuing to increase Sunday evening across inland areas. Crater Lake has been reading unhealthy since late afternoon. By Monday morning, another northeasterly wind will carry smoke further west into the Illinois Valley and Curry County coastline. However, the offshore flow to start the week off will be weaker than the past two nights. This will mean less smoke along the Coast and more smoke for inland areas, such as Medford (at least compared to Sunday morning). Again into the afternoon hours, expect winds to shift more north, northwesterly which will then help that smoke travel inland more.
The main topic of discussion is the problematic week on hand for weather. An area of low pressure currently positioned off to our south and west will break off from the jet stream this week. By this I mean a cut off low pressure system will form, and create an unstable air mass over the Pacific Northwest. A southerly wind will bring increasing moisture to the viewing area, and rising instability. With that, thunderstorms will then be favorable — not only for the higher terrain and East Side, but areas west of the Cascades as well. The activity should begin Tuesday, with more isolated thunderstorms a possibility for the West Side then. The thunderstorm threat will continue continuously through Saturday, with the best days for thunderstorms over Jackson & Josephine County on Thursday and Friday. These are the days when showers and thunderstorms will have the most coverage.
The first half of the week will introduce dry thunderstorms, but as moisture steadily rises, the amount of rain capable of falling will as well. This is definitely good news, but even so, the strong winds and lightning that accompany storms is not going to help the current situation over Southern Oregon & Northern California. The weather pattern that will be in place all week is an ideal scenario for thundershower activity over the Rogue & Illinois Valleys, meaning any storms that develop will have to be watched very closely.
With temperatures steadily rising through midweek as well, fires could easily spread. A little bit of good news is that winds should stay fairly calm for most of the next several days, other than the late afternoon hours when temperatures peak.