June 28, 2023

Is Washington State on Track for a Severe Fire Season?

Will the Northwest be the Epicenter of Wildfire This Year?

My friends at the Seattle Times are up to their wildfire dramatics again.

A front-page headline suggests that the Northwest will be the wildfire "epicenter" of the U.S.

and within the article, they claim that last year's Bolt Fire was a

"dress rehearsal for more frequent fires along the western flank of the Cascades as climate change drives warming summers"

So what do the actual facts say about the potential for wildfire activity this summer?  Is the scary hype based on reasonable science?   Is climate change/global warming behind the Bolt Fire and this summer's fires?

This blog will lay out some of the facts and give you a more nuanced and science-based view than you will get in the Seattle Times.

The Current Wildfire Statistics and Situation

So far, this has been a relatively normal to below-normal wildfire year in our region.  

Consider the latest wildfire statistics from the Washington State Department of Natural Resources (below).  These graphs are for Washington State and only for DNR lands, which are located mainly over the fire-prone lower elevations of the regional terrain.

We are running BELOW NORMAL for both fire numbers and fire area.

Next, let's turn to Northwest fire statistics from the Federal Northwest Interagency Coordination Center, which show that current fire numbers are near normal (blue line).  We were above normal in May and then fires dropped back during the moister weather of the past few weeks.

So far there have been very few forest burns.  Most of the fires have been grass/range fires, and that is certainly true of the larger fires.  

Why the significant grass/range fires?  

Because we had wet conditions last year that led to bountiful grass growth.   A great place to get information on this is the USDA FuelCast website.  Here is a figure from FuelCast showing the amount of dead fuel (mainly dried grasses, pounds per acre).  There is a major fire threat when this gets above roughly 800 lb per acre, which includes large swaths in eastern Washington.


Grasses dry quickly during early summer (even after rain, only a few hours will dry grass sufficiently to burn).

So we have a flammable threat east of the Cascades that has NOTHING to do with global warming.  It is from prior wet conditions, the opposite of global warming expectations.   All it takes is some careless ignition during windy conditions to burn a large swath of rangeland, and several such fires have already occurred this spring.

The Current Moisture Situation

We have had a persistent situation with near-normal moisture east of the Cascades (where most of the wildfires historically occur) and drier-than-normal conditions over western Washington.  The current National Drought Monitor graphic indicates this (see below)
Taking a broader, more objective view, is the latest Palmer Drought Severity Index, which combines the effects of BOTH temperature and precipitation.  Near normal conditions over eastern Washington and moister than normal over eastern Oregon.  Western Washington is drier than normal.


As I have mentioned in several blogs, the general atmospheric circulation over the West Coast has been highly anomalous this past spring, with a trough of low pressure over California.  This has dried out western Washington and Oregon while bringing wet conditions to California.

It has also brought persistent thunderstorms and rain over eastern Washington, which has lessened the wildfire threat there (see sample graphic below from the NWS).


As shown by the June rainfall map below, there has also been substantial precipitation over the Cascades, including the western slopes.


As a result of this precipitation and mild June temperatures (no major heatwaves), the fuel moisture around the region is not particularly low, and, in fact, moister than last year at this time.  And last year was a very low fire year, by the way.

To illustrate that the situation is better than last year, below is the 10-hr fuel moisture at Leecher, WA, not too far from Omak (2023 is on top, 2022 on the bottom)


So we have had a normal to below normal wildfire year so far, there is no drought over eastern Washington and Oregon, and fuel moisture levels are not particularly dry due to substantial rain east of the Cascades and the absence of major heatwaves.

Doesn't sound like a seriously threatening wildfire situation at this point, does it?

The national epicenter of wildfire disaster?

Looking Forward

Recently, West Coast weather has been dominated by troughing/low pressure over the Southwest US., bringing cool and moist conditions to California and lots of thunderstorms east of the Cascades (see upper-level (500 hPa pressure, about 18000 ft) map this morning to illustrate.  Blue indicates lower-than-normal pressures/heights



But this week there will be a major change, with a weak ridge of high pressure moving over the West Coast (the forecast for last Friday is shown below)


This pattern will be in place for much of the next week. We will warm a bit and the thunderstorms will fad back east of the Cascades.  As shown below, western Washington will warm into the mid-80s early next week.


This is not a situation that produces major heatwaves or strong winds. Surface fuels will dry out more and some grass fires could occur.

Importantly, many of the models predict a return of the West Coast trough situation, which would bring back the conditions we have enjoyed during the last week (see the upper-level forecast for the morning of Saturday, July 8).  Conditions that are not favorable for regional fire.



The bottom line of all this?  The wildfire situation now is pretty typical and there is no reason to predict a particularly severe summer wildfire season in the Northwest.   There will be wildfires, so folks need to be careful.

And one more thing.  The Seattle Times article stated that the Bolt Fire of last year was a "dress rehearsal" of the effects of climate change.

Simply wrong.  

Western Washington wildfires inevitably are associated with strong, easterly (from the east) winds occurring at the end of the (normally) dry summer.

The latest research (including material I have published) is that such winds will WEAKEN under global warming.  Also, let us not forget that the Bolt Fire was caused by an illicit fire and burned through a previously cut forest with lots of debris sitting on the forest floor.








20 comments:

  1. Thank you for for pointing out the inaccuracies of the Seattle Time article. I see red flags whenever I read that "event X was caused by human caused climate change" without citing a credible source. This statement is a scientific conclusion it should not be made without attribution. Hopefully it will be a quiet fire season. We'll know in three months.

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  2. Correct me if I'm wrong, but I think it is fairly difficult to predict the fire season. This is especially true when it comes to smoke. I would imagine range fires are easier to predict, but they tend to produce less smoke. In contrast, last year was setting up to be a particularly light year for fires, until we got hit by two things that were very difficult to predict. One was an usually dry autumn. Areas that were burning just kept burning. Then there was the Bolt Fire, which was man made, and thus impossible to predict. If the idiot(s) hadn't have started that fire, Seattle (and even many of the Cascade Mountains) would have been quite clear.

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    1. Of course, it is difficult. Extended forecasts are hard and it difficult to predict whether someone will do something dumb (or even try to start fires). But last year was a low wildfire season for our region...cliff

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    2. " difficult to predict whether someone will do something dumb"
      Well, I predict more than one will do something dumb and than something dumber. Watch the animal encounters coming from Yellowstone NP. There have been several. Dumb. Recently, a person left the boardwalk and dipped her toes into a geothermal pool. Dumber.

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  3. Guessing you won't publish this, but you made a similar prediction last year and singled out David Horsey and the ST this way:

    "And ST's David Horsey doesn't stop there in inducing fear:

    'That means another summer of wildfires. And that means smoke....there’s a good chance of that perfect August weather in Western Washington being smothered in an acrid cover of smoke blowing in from fires to the north, the east and the south.'"

    You also stated:

    "If things work out as the data suggests, I hope Mr. Horsey and the Seattle Times will consider the following idea for a cartoon later this summer when the smoky future they predicted does not materialize."

    Of course, you were wrong. Comments? Reflections?

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    1. Fred..you comments doesn't make any sense. My forecast was quite accurate. Last year was a low wildfire year for the region. Please check the statistics. The Bolt Creek Fire was in SEPTEMBER, not August, by the way.. Horsey was totally wrong, as he is for most of his climate comments....cliff

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    2. Fred, looks like you are trying to find something that does not exist. It's like the republicans/Trump trying to find votes that did not exist for Trump when Biden won, fair and square.

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    3. Fred, why are you bringing an ex - POTUS into this discussion?

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    4. While last year (2022) was a low fire year with regards to acres burned, especially in Eastern Washington, it had, as many of our recent summers, a high potential for large fire loss, due to the extended periods of warm, dry weather. Acres burned in a season does not always correlate with the weather of that season. There have been a number of very warm, dry summers in the past in Eastern Washington (i.e. 1967, 1973 and several in this century) that had relatively few acres burned. These years had the necessary conditions for large fires, extended warm, dry periods, but lacked ignition sources during the critical times, mainly no dry lightning storms. Dry lightning storms in association with extended warm, dry periods are the main factors in most of the large fire loss years in Eastern Washington. Unless we go into a period of cooler, wetter weather this summer, I believe this year has the potential to see large fires, as it has been warm and mainly dry thru much of May and June. The recent moist period saw some heavy showers but these were localized and the return to warm, dry weather currently predicted will eliminate the benefit of this rain in a short time in these wetter spots while the places that did not get the rain will become even more critically dry..

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  4. You should blog about climate change and the earth's spin article next. Nasa scientist quote “it’s impressive they were able to tease that out of the data,” That is a red flag comment if I ever did here one.

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  5. In the article's first several paragraphs the author states that "Washington saw the fewest acres burned in a decade last year, after the second- and third-worst fire seasons on record in 2020 and 2021." The accuracy of this statement is highly questionable in light of the following graph from the U.S. Interagency Fire Center for the entire country.

    https://images.app.goo.gl/wdBvXXcLpsdiBBB56

    Which shows the U.S. experiencing 5 times the number of acres burned in the 1920s than occurred in the recent years.

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    1. Keep in mind the 1920-30s predated fire suppression efforts and was during the dustbowl.

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  6. MSM's job is to sell advertising and subs. No expectation of truth or ethics so people need to use some objective reasoning (what's that???). Plus, the meta of this fire season is that is been perceived as being atypically severe since the major eastern cities are getting brutally hazed. Locally, who knows but the cynic's (or realist's) expectation is that come late summer/early fall we will be choking on smoke at least once. Either from our own local smoke or smoke exported from elsewhere. Very few are ever directly effected by the flames but the smoke is what gets millions of people grumpy.

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    1. "MSM's job is to sell advertising and subs" and to develop given narrative.

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    2. Tell people what they want to hear in whatever mainstream echo chamber the consumer has tuned into and market products that most likely aline with that target audience=profit. CNN and Fox News are equally guilty. Maybe more so for Fox since they have higher viewership. So, you are not wrong on the narrative bit. They are exploiting the biases and fanning the flames further. Media is just a business. Truth? Ha! It's all about money.

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  7. The North American Seasonal Fire Assessment and Outlook/National Interagency Fire Center currently predicts above normal potential for significant wildland fire for all of Washington throughout the summer and into early fall.

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    1. Those forecasts are out-if-date and nearly a month old. Their 7 day forecasts, which are current, show low risk at this point.

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  8. What's the source to view the graphs for the 10-hr fuel moisture for Leecher? I'm particularly interested in viewing data from Pierce County. Thanks!

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  9. I'm glad Cliff pointed out that the Bolt Creek fire was not only human-caused, but took off in a recently logged area which allowed the easterly wind to really tear through. As we speak, the U.S. Forest Service is ramping up logging/thinning operations on the Mount Baker-Snoqualmie National Forest, euphemistically for "restoration" and beyond anything seen along the west slope of the Cascades in 30 years. This will mean earlier drying of fuels in the summer (due to more sunlight reaching the forest floor), greater exposure to wind events, accumulations of slash, and un-patrolled logging roads which are an open invitation to every slob who wants a campfire to shoot at. Watch for fires emerging from these newly logged areas in the summers to come, as well as the Forest Service quickly washing its hands of any culpability. There's no better recipe for west slope forest fires than what our federal government is implementing right now.

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  10. I doubt any thunderstorms and rain associated with in eastern Washington is really diminishing the wildfire threat there. Most of this rain is localized to the Cascade crest and the bigger issue is the shrub steppe interface to some of the larger cities there in the Central Basin

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