Rain is coming, right onto many of our large fires.

This UW ensemble precipitation
forecast map shows at least light rain
predicted over much of Washington,
notably skirting the Columbia Basin. 

In most of Washington, any sighs over a cool wet weekend will fill your lungs with clean air.

A breezy weather pattern has started to move across the state. It’s bringing fresh Pacific air and deflecting smoky air from fire complexes in southeastern BC and southern Oregon and northern California away from Washington.

That leaves no smoke worries west of the Cascades, but fires on the range’s east slope and in the Okanogan Highlands can still pack a smoky punch locally.

The Washington Department of Ecology will extend an Air Quality Alert (AQA) for the Methow and Okanogan River Valleys, the Lake Chelan area and Yakima County until 10 a.m. Monday. Particulate matter (PM2.5) levels could reach Unhealthy for Sensitive Groups levels or Unhealthy levels in those areas.

The band of light precipitation will fall mostly in north central parts of Washington, as shown by the ensemble mean of all models. The AQA is being extended despite the rain because fires are expected to continue smoldering for a while. There is not enough rain to extinguish them altogether.

A Super Scooper firefighting plane
flies through evening haze Thursday
over Ecology's Union Gap office.
(Photo: Eiko Urmos-Berry)

The Schneider Creek fire that’s producing scenes like the photo here from Ecology’s Union Gap office last night may miss out on much of the rain.

Cooler temperatures, though, will help fire crews, regardless of rainfall.

The weather package also includes thunderstorms and wind gusts. While those can start or fan wildfires, the overall benefit of cooler air and rain should help fire crews make good progress over the weekend. Sunday should be breezy and drier, with more wet weather forecast to follow early next week.

We’re posting updated local smoke forecasts for Washington’s major fires on this blog’s Local Smoke Outlooks tab. And, our maps show the most current PM 2.5 monitoring information.

The Northwest pattern is back. Except near fires, we’re clear of regional smoke.

 This week is a great time to appreciate the classics, at least when it comes to Pacific Northwest weather patterns. 

End of the week rain outlook for
Eastern Washington and Northern Idaho.

A low pressure system arrived late Monday from the North Pacific, bringing some rain showers to some of the fires burning in northern Washington. The system is finishing its pass over the region. A similar batch of rain, clouds and cooler temperatures should arrive late Friday. Not a ton of rain, so don’t pin too many hopes on it.

 In the meantime, we’ll have two days of high pressure weather, bringing light winds and warmer temperatures, but at seasonal levels.

 This between-storms weather will mean that smoke from fires on the east Cascade slopes and northeastern high country will affect nearby areas intermittently. The low pressure system’s cooler air and precipitation should dampen fire intensity, and give fire crews a boost in their containment efforts. Higher winds are part of the low pressure package, though, with their mixed blessing. The winds bring in fresh air, but fan fires, too.

A weather satellite photo of Washington this morning,
with smoke plumes visible from fires in
Okanogan, Chelan and Yakima counties. 

 With localized smoke remaining a concern, the Department of Ecology issued an Air Quality Alert for Okanogan, Ferry, Chelan, and Yakima counties until further notice.

 As for the classics, more low pressure systems may be on the way, interspersed with calm, warmer high pressure. A pattern like that confines smoke to communities around fires, often extending several dozen miles downwind, during the calmer phases.

 When the light summer storms pass by they bring at least cooler temperatures, if not precipitation. On a cloudy or rainy Washington weekend, that’s still a breath of fresh air.

 Please check this blog’s Local Smoke Outlooks tab for more about smoke conditions around Washington’s areas with major wildfires.

We’ll get a brief taste of fall weather. It could help dampen wildfires, but may bring smoke from BC.

Hope mixes with uncertainty when it comes to forecasting this week’s wildfire smoke.

Some cooler weather tinged with rain over the next two days would likely make fire crews smile if the package didn’t include some stiff wind gusts. 

A low pressure system will swing by from the North Pacific pushing a cold front tonight and tomorrow that will cut across Washington and displace hot dry air from a high pressure system centered over the Great Basin. But, later in the week, after this low passes, the weak high pressure system will spread back over Washington.

Smoke under clouds: This webcam picture from a resort near Winthrop shows today's north central Washington smoke haze, under an overcast of regular clouds.

Some light rain will help throughout the state, with relief especially welcome along the east slopes of the Cascades and northeastern counties. Rain will also pass over British Columbia, which may help with the fires whose smoke sank onto much of Washington Friday and Saturday.

The other side of this coin is wind. Gusts could reach 40 miles per hour, which will likely fan fires and speed their spread. The wind direction will shift from west to north. That could push a lot of the BC smoke our way. It’s unclear how much smoke will be generated and mixed down to the surface. Our forecasting models disagree so far, but we hope to bring that into better focus over the next two days.

A NASA satellite view of Washington from late this morning. Cooling clouds blanket northern and coastal areas. Smoke plumes can be seen near Yakima and Clarkston.

We’ve issued an Air Quality Alert for Okanogan, Ferry, Douglas, Stevens, Pend Oreille, Chelan, Kittitas, and Yakima counties through 10 a.m. Wednesday due to smoke from local fires and the uncertain amount of BC smoke that will move south tomorrow.

Western Washington will have plenty of fresh coastal air for at least another day. There will be smoke overhead starting Tuesday, with potential smoke impacts at high elevations on Wednesday. 

Be sure to open the “local smoke outlooks” tab on this blog for specific warnings and information about Washington fires.

Relief in western WA, not so fast for eastern WA

Overhead smoke took the edge off the heat yesterday and will do so again this weekend. 

"Aw c'mon Ranil, that's of little consolation! When will the smoke clear?"

Today and tomorrow. But...

Eastern WA

Strong west winds will help reduce the smoke this evening through Sunday, but also raise the risk of new fires. So while most areas will see some improvement, not too many communities will see Good air for long. Existing fires are projected to keep puffing out smoke. Conditions are expected to worsen mid-week as another ridge builds. Please see the 5-day forecast map above.

Western WA

Ground level smoke will continue to clear today, although elevated smoke from CA fires will flex its muscle as it sails (mostly) overhead, giving us pretty sunsets. Expect a smoke-free western WA for a few days at least. Got to keep an eye on possible east winds mid-week, which can transport smoke from across the Cascades. 

Here's a comparison of fine particle pollution (aka PM_2.5) levels across the state so far this season. Who had it best/ worst? You decide.

Wildfire Smoke and Heat: A Double Whammy

When there is smoke, there is often heat. Combined, heat and smoke can become especially dangerous. How can I protect myself from both?

Staying inside and keeping doors and windows closed will keep smoky air out of our homes, but it can be hard to manage indoor temperatures while doing so. If it’s hot indoors and you don’t have air conditioning, these steps can help you stay cooler inside during poor air quality:

• Reduce the heat indoors: close curtains or shades during the day, use your stove and oven less.
• Do not rely on a fan as your only cooling source. While electric fans might provide some comfort, they won’t prevent heat-related illness when temperatures are very hot.
• Cool off by taking a cool bath or shower. Use ice packs or put your feet in cool water.
• Stay hydrated, especially with water. Avoid sugary or alcoholic drinks—these can be dehydrating.
• Go to an indoor place that is cooler—even if only for a few hours. Dial 2-1-1 or use the statewide online resource to find cooling centers near you. Language assistance is available.
• If you plan on visiting a cooling center or staying with friends and family to get a break from the heat, make sure to follow local COVID-19 indoor gathering requirements and respect the rules of the room when it comes to masks.
• Track the air quality and open your windows when the air quality improves and outdoor temperatures are cooler than inside.
• If it’s still too hot and the outside air quality is poor: open windows when outdoor temperatures are cooler than inside and take steps to filter indoor air. 

 As always, for wildfire smoke:

• Reduce outdoor physical activity and take it easy inside.
• Set air conditioners to re-circulate.
• Improve filtration of indoor air: upgrade your home HVAC system filtration to a MERV 13 filter (or the best your system can handle), buy a HEPA portable air cleaner, or build a DIY box fan filter.
• There are technical details involved with all of these options. See our previous post.
• Don’t add to air pollution. Avoid burning candles or incense, smoking, diffusing essential oils, broiling or frying foods, and vacuuming (unless your vacuum has a HEPA filter).
• Seek clean air elsewhere, if the air quality remains poor and it is not possible to keep the air in your home clean or cool.

For more information see the Health Information Tab or visit WA DOH’s Smoke from Fires webpage.

Western WA update: Yikes! … but hang on,… this too shall pass…

 We awoke to see Washington was in a smoke bath, and western WA was not left out this time.

Yesterday, smoke from British Colombia fires started pushing into the Puget Sound at the ground. And, yesterday and overnight, there was continued strong smoke production from fires in Central Washington, Oregon, and California. And, we had a very complex wind pattern, with very different flow at different altitudes. Smoke was heading south from Central Washington, and swirling clockwise back up to the Puget Sound. This overall mess brought much of the Puget Sound into UNHEALTHY FOR SENSITIVE GROUPS, which is where we are this morning. 

Looking ahead… there’s still looks to be a fair amount of smoke up above us (see the vertical profile plot below, the dark grey above about 1000 m). And, it’s likely we’ll get some of it mixing down today. So, in the Puget Sound, we're expecting similar or worse smoke at the ground through most of today. Some places could reach UNHEALTHY, but it's really tough to know precisely how much smoke is up there.

But, the westerlies should start picking up tonight, and much of this will move to the east overnight. By Saturday morning, most of the Puget Sound should improve and be back to MODERATE or GOOD air quality. We may see some California smoke pass overhead on Saturday and Sunday... but the Puget Sound should be able to breathe easy again...

Western Washington’s smokeless streak comes to an end

After skirting serious smoke impacts all summer, western Washington’s luck has finally run out.

Northwest winds are blowing smoke from fires in British Columbia into Whatcom, Skagit and Island counties, while winds along the coast will begin dragging smoke from Californian fires into communities around Grays Harbor and along the Olympic Peninsula.

Friday (8/13/2021) Smoke Model Forecast Image

 

Some of that smoke will make its way inland over the Puget Sound region and, just like we saw during the record-breaking June heat wave, high temperatures Friday may also lead to biogenic aerosol formation and enhanced ozone production, adding even more pollution to the mix.

So here’s the rundown: Expect air quality readings in the Moderate to Unhealthy for Sensitive Groups range on Friday across much of western Washington, with a few spots hitting Unhealthy. A plume from the Schneider Springs Fire northwest of Naches may also pass over the central Puget Sound on Friday morning and bring much higher smoke concentrations for a few hours.

GOES-17 Imagery (8/12/2021)

The Northwest Clean Air Agency has issued an air quality alert for Skagit, Island and Whatcom counties, the Olympic Region Clean Air Agency has alerts for Clallam and Jefferson counties, and Puget Sound Clean Air has alerts for King, Snohomish, Pierce and Kitsap counties. San Juan County should expect Moderate-to-Unhealthy for Sensitive Groups air quality.

The good news is that this is likely to be a short-lived exposure. A cold front arriving Sunday should blow all of this smoke out, and air quality should begin improving Saturday even before the full front arrives.

Break’s over for eastern Washington

Triple-digit temperatures and low humidity have combined to nix the air quality improvements brought on by last weekend’s cooler, wetter weather. 

Wildfires in Okanogan are churning out smoke again, and the Schneider Springs Fire northwest of Naches is now pushing smoke into the Yakima Valley. 

Not great!

Air quality across eastern Washington started Thursday in the Unhealthy for Sensitive Groups to Unhealthy range.

Those air quality impacts will worsen going into Friday, then the smoke will begin to thin Saturday ahead of a larger cold front set to arrive Sunday. 

The Washington Department of Ecology has issued an Air Quality Alert for all of eastern Washington through 10 a.m. Monday. 

By late Sunday, air quality should be much improved, if we can just avoid new fire starts. However, more local impacts in Okanogan, Ferry and Yakima counties are likely to continue into early next week.

What’s the problem with a little nice weather?

You may have seen the forecast for another heat wave this week.  While temperatures in the 90s already elicit groans from native PNWers, there is another reason to wag your finger at the heat.

High-pressure systems not only lead to high temperatures but also move air in a clockwise direction.  This can bring in smoke from Northern CA and move smoke from Eastern to Western WA.

Currently, Washington fires aren't putting out that much smoke. Western WA could see some smoke from the Schneider Springs fire NW of Yakima on Thursday or Friday with the easterly winds. But one of our generally better performing models, the HRRR, has the smoke staying upper level for now. So, we aren’t expecting a lot of Central/Eastern WA smoke crossing into Western WA this week.  Of course, the local impacts of those fires will continue to be significant and people living near the fires should take precautions.

Highlighted in this image are the Schneider Springs fire northwest of Yakima and a collection of three fires on the Colville Reservation.

In contrast, fires in northern CA are putting out a whole bunch of smoke.  Check out this satellite image from this morning.

The smoke is starting to pool off the coast and could be brought northward with the clockwise rotation of the high-pressure system starting Thursday. It will take some time to make it up here so we may begin to see hazy skies late Thursday or Friday. However, that smoke is staying upper level for now.

Overall, we expect mostly high-level smoke Thursday through Saturday with minimal impacts on the ground.  Strong westerly winds are predicted to return by Sunday, which should help clear out any smoke.

And last but definitely not least, expect MODERATE to UNHEALTHY FOR SENSITIVE GROUPS ozone levels near the west side of the Cascades on Wed-Sat due to high temperatures brought on by the aforementioned high-pressure system.

Why is the dot grey? And other fun facts about the smoke map!

The fire and smoke map at the top of this page is a great tool to check current air quality conditions. Clicking on a site gives you information about current conditions, short-term PM2.5 trends, and monitoring site information. You can also see locations of active fires and smoke plumes. Below are a few common questions about the map; let us know if we missed anything in the comments!

What do the different markers on the map indicate?

Circles are permanent monitors, operated by state, local, and tribal air quality professionals. Triangles are temporary monitors, and the squares are privately owned low-cost sensors from Purple Air, with EPA’s correction equation applied.

Why is the dot at my local air monitor grey?

There are a few different reasons why your local air quality monitor is grey:

•         We have lost communications with the monitor and can’t receive data
•         There isn’t enough data to calculate an air quality index value (due to previous lost communications)
•         An air monitoring operator is conducting a calibration, quality control check, or maintenance
•         Quality Assurance personnel are conducting an instrument performance audit

Clicking on a site gives me information about a NowCast AQI. What is a NowCast?

The dots on the map are what EPA refers to as the “NowCast,” which relates current and previous hourly PM2.5 concentrations to the Air Quality Index, resulting in the color scale you see on the map. The NowCast is meant to give you a sense of what precautions you should take NOW, based not just on the most recent reading, but also on what the trends have been. The NowCast uses longer averages during times when air quality is stable and shorter averages when air quality is quickly changing. So, if a new fire starts and air quality is quickly deteriorating, the NowCast would show a higher advisory level than what the most recent reading would indicate (and vice versa when air quality is improving).

You also may notice that the hourly concentrations on the “Recent History” tab are different than the NowCast AQI—again, that’s due to how the NowCast is calculated using multiple hours of data.

Why is the purple air sensor closest to me different from the nearest regulatory monitor?

Low-cost sensors are great tools to assess local air quality conditions. Differences in terrain and meteorological conditions between the regulatory monitors and low-cost sensors can lead to differences. Regulatory air monitors also follow detailed rules in where they are placed, their distance from local sources, and their inlet heights.

Why is the smoke blog map different from other maps?

Many companies and apps report air quality and air quality index values, but in many cases it’s unknown how their Air Quality Index values are calculated or what data is used. It’s a best practice to look to public agency sources for trusted air quality information.

A few other fun facts for your Monday morning:

For your fun air quality instrumentation fact of the day, the figure below shows what it looks like when a spider crawls into a nephelometer, which is used to measure PM2.5 concentrations.

Yes, spiders are everywhere, including in our air quality monitoring instrumentation!

And for the data folks out there, if it seems like it has been an early start to the fire season in the central and eastern regions of the state, you’re not wrong! Ranil mentioned it in an earlier post, and a regional and county breakdown of the number of days spent in each AQI category since 2011 (only including summer data up to today’s date) indicates the same: