CA fires continue to impact the local PM2.5 AQI. Aged smoke aloft over northeastern US can be contributing to regional moderate PM2.5 AQI. CA and OR wildfire smoke are predicted to impact local PM2.5 AQI and surface low pressure systems would promote smoke transport aloft. Northern Canadian wildfire smoke are not likely to impact the US AQI, but keep an eye on aged smoke transport later in the week. Should OR and CA fires continue, or grow, 500 mb winds would support any smoke aloft to be transported easterly/northeasterly respectively. Also if any southern Sask. or Alb. wildfires develop smoke could be transported into northern US.

OR and ID wildfire smoke is impacting poor PM2.5 AQI in several northern US states. Aged smoke from earlier B.C. and Sask. wildfires remain visible aloft over the Midwest US, with minor impact to the surface AQI. OR and ID wildfire smoke transport will continue to impact the northern US AQI. Aged smoke aloft could potentially be transported to the surface with the high pressure system over the Midwest. Low pressure systems in the PNW and Sask. will promote wildfire smoke transport aloft and 500mb low pressure to continue the transport easterly from the wildfire sources.

Wildfire smoke is being transported aloft into the northern Midwest US. CA, OR, ID fires are continuing to impact local AQ with minor transport east. Canadian wildfire smoke (Sask. and NT) will continue to be transported into the US – aged smoke from the NT is likely to impact the northeast and Sask wildfire smoke to impact the Midwest. Chances of rain in Midwest on Wednesday could help to clear up the AQ. Should Canadian wildfires continue, the high pressure system over the northeast will promote the transport of smoke aloft to the surface. Western US wildfire smoke likely to remain near the surface with the local high pressure systems.

CA and OR wildfires continue to contribute to local unhealthy AQ. Wildfire smoke is not contributing to moderate AQ in much of the US. Canadian wildfire smoke will have minimal, if any, impact to AQ in US. A and OR wildfires will continue to have regional AQ impacts. Canadian wildfire smoke is not likely to be transported to the US, but will need to keep an eye on aged smoke impact.

CA and OR wildfires are impacting air quality (mod -> unhealthy) in PNW US. Mod AQI in eastern US is minimal, if any, impact from smoke transport. CA and OR wildfire smoke is predicted to be transported east and impact AQ in CO, ID, WY, MT. Canadian wildfires will have minimal impact to AQ in US. High pressure aloft over western/central US could promote smoke transport aloft from CA and OR wildfires as well as continued impact to western US AQ.

Oregon wildfires are impacting air quality in OR. Canadian wildfire smoke is impacting PM2.5 AQI in upper Midwest US. Canadian wildfire smoke is forecasted to continue to impact the upper Midwest US AQ. OR and CA wildfires will also continue to impact regional AQ with low pressure system suppressing long range transport. Strong low pressure aloft over Canada will likely to promote smoke transport north/northeast with potential impacts in northeast US AQ. OR and CA wildfire smoke could impact coastal AQ later this week.

Oregon wildfires are impacting air quality in OR, ID, CA. Moderate PM2.5 AQI in much of southern/eastern US, but not related to wildfire smoke. Likely chances of rain in the Central US. Smoke from Sask. Wildfires are forecasted to impact AQ in the Midwest US behind a cold front further south. OR and CA wildfire smoke continue to impact AQ in western US. Persistent high pressure system aloft over southern US will likely dampen longer range transport of smoke from CA fires. Transport of Sask. wildfire smoke is also likely to continue to the Midwest US, but potentially minimal impact to AQ.

In general, the US air quality is not being impacted by wildfire smoke. A few patches of moderate air quality are present in the Southern US. Smoke transport form Montana and Georgia fires are forecasted to impact AQ to the south east and north east,respectively. Likely chances of rain in the Central US and snow in the Northwestern US. Wildfires in B.C. Canada will not impact local AQ. Likely chances of rain ahead of strong low pressure systems and warm fronts in the Central and Northeastern US. Smoke transport from Canadian wildfires is not predicted to impact the US.

In general, the US air quality is not being impacted by wildfire smoke. A few patches of moderate air quality are present in the Central and Eastern US. Likely chances of rain ahead of the cold front in the Central US and snow in the Northwestern US. Canadian wildfires are predicted to subside. However, aged smoke off shore the east coast is forecasted to be transported back on shore in the southern US and potentially have a moderate impact to air quality in the region. Forecasted low pressure aloft with strong winds over Canada and northern US coupled with a high pressure system at the surface could transport smoke into the US if any wildfires were to begin.

Smoke from Canadian wildfires is being transported north and is not impacting air quality in the US; however, southern CA fires are impacting the local region. Cooler temperatures and likely chances of rain around cold fronts in the northwest and central US through Wednesday. Smoke transport from northern Canada (B.C. and Alberta) is not predicted to impact the US air quality. A forecasted low pressure aloft over northwest US with strong winds northeast coupled with cold fronts at the surface along the trough suggest little impact to the US air quality should Canadian fires persist; however, the high pressure system over the northeastern US could promote transport to the surface should smoke appear a loft.

Smoke from Canadian wildfires is being transported northeast and is not impacting air quality in the US; however, fires in northern California/Oregon, and fires in Kansa/Nebraska are impacting the local region.Chances of rain may help contain the fires over British Columbia and Kansas. Smoke transport from Canada is not predicted to impact the US air quality. The impacts of fires in northern California/Oregon are predicted to be local. A surface high pressure system over Canada could promote smoke transport into the north of US (including Montana, Wyoming, North Dakota and South Dakota).

Smoke from Canadian wildfires is being transported north and is not impacting air quality in the US; however, northern CA fires are impacting the local region. Cooler temperatures and likely chances of rain around cold fronts from the southern to northeastern US through Wednesday. Smoke transport from Canada (B.C. and Alberta) is not predicted to impact the US air quality. A low pressure system aloft over Canada is forecasted to extend into the northern US and could shift smoke transport further south. At the surface a stable high pressure system in the region could promote smoke transport to the surface and impact the air quality in the northern to central US.

Smoke form wildfires in northern Alberta/Sask. Canada is being transported south and impacting air quality in the north central US. Northern California air quality is also impacted by local wildfire smoke. Under warm and dry conditions the Canadian wildfire smoke will most likely continue to be transported further into the Central US ahead of a cold front system. Central CA is forecasted to be impacted by smoke from the Northern CA wildfires. Warm and dry conditions will persist in the Central US. As a stable high pressure system sets up, any smoke already in the region will likely persist through Friday.

Active fires in B.C. Canada, and WA US continue to cause poor air quality in the region. A combination of persistent smoke transport and stagnate weather are impacting the air quality in the Central and Eastern US. Likely chances of rain are predicted over the PNW along a cold front through Tuesday. A high pressure system over the central and southern US through Wednesday and impacts to air quality from smoke will persist in the region. A stationary front forecasted along the central US along with a low pressure system could help to clear out lingering smoke aloft in the region. Need to keep an eye on potential fires in southern Canada.

Active fires in southern Ontario Canada could impact the northeast US should wind direction shift. Smoke transport from northern Canada not likely to reach the US. Smoke transport from Oregon fires is predicted to impact northern California air quality at least through Wednesday. Low pressure system sets up over southern Canada Thursday. If smoldering fires pop up in the region, smoke could be transported into the northern US. If the Oregon fires persist, smoke could transported further to the west.

Active fires in North Dakota (local) and transport from Canadian fires impacting air quality in North Dakota and moderately in north-central US. Cold front sets up along southern Canada coupled with fair weather could promote smoke transport from North Dakota fires into central US on Tuesday. Wednesday rain ahead of a southern warm front in Central US could dampen transport and help improve the air quality. Keep an eye on the transition from cold to warm fronts may push back on smoke transport from Canada into the northern US.

Pocket of unhealthy air quality around Los Angeles CA under local fire conditions. Stationary front along NW to SE US separating high pressure systems with little chance of rain.​ Likely chance of rain over the SW US while stationary front persists. Unlikely chance of any smoke transport from any western US fires inland (at least to the surface). A cold front, followed by a high pressure system, sets up in the northern US while a warm front is situated over southern US. Central US could see smoke aloft should Canadian fires persist, with a chance of transport to the surface. ​

Moderate to Unhealthy air quality will persist through the day in the Central US with a pocket of very unhealth air quality in central Oregon. Forecasted stationary fronts through northwestern and central US through Wednesday (July 26) could lead to worsening air quality in the western US should wildfires persist. High temperatures and dryer conditions in much of the US through Friday July 28. Stationary fronts in the western US and high pressure system could limit transport to the Central US.

Today a band of poor air quality will persist through the central US and as smoke continues to be transported from the northwestern Canadian fires. Tuesday and Wednesday the cold front will continue to move south with a likely chance of rain behind the front. The eastern US will continue to experience moderate to unhealthy air quality. Thursday brings likely chances of rain and a low pressure system and forecasted improvement to air quality in the eastern US.

Rain throughout the Central US over the weekend improved the air quality to start the week. Likely chance of rain along the front in the central US will suppress smoke transport from the north western Canadian fires. Should the fires persist through the week, the central US could see more smoke transport and worsening of air quality by the weekend as a high pressure system moves in.