With the recent grass/range fires in Eastern Washington, there is some interest in whether conditions there have gotten drier or warmer.
How unusual have precipitation and temperature been this year?
Let's find out!
I will start with the NOAA Climate Division dataset, which is derived from multiple climate observation locations in each division (the climate division map for Washington State is shown below).
For precipitation, there is little long-term trend.
For temperature, there is a warming trend of about 0.2F per decade. Some of that represents the global warming signal.
Moving to the lower-elevation Columbia Basin, there is again little overall trend in precipitation over the period, but there have been a few dry years in the past decade.
The temperature plot for that area shows warming, particularly during the past decade. Some of that warming undoubtedly reflects the global warming signal (although land use changes, urbanization, and other factors are certainly significant as well). Same upward rate of 0.2 F per decade.
What about this year?
Here are the plots of precipitation and temperature at Ellensburg in eastern Washington for June 1 to July 28.
A small warming trend in temperatures, with this year not being extreme at all-- near the long-term mean.
For precipitation, there is a LOT of historical variability, with this year being relatively low (fifteenth lowest out of 67)
In short, conditions in eastern Washington have hardly been exceptional for the first half of summer 2026, with a very modest warming signal evident.
This is why the fuel moistures were near normal.
The only reason we had significant grass fires was due to a huge amount of lightning, which has little to do with global warming.
You said the huge amount of lightning in E Washington has little to do with global warming. When I search for confirmation several studies and articles are cited that disagree stating that for every 1°C (1.8°F) of global temperature rise, lightning strikes increase by about 12%. Also... Stronger Updrafts: Warmer air holds more moisture and rises faster, creating powerful storm updrafts that build up electrical charges.More Energy: Higher surface temperatures feed convective energy into storm systems, making individual thunderstorms more explosive??? How and where can I find studies that agree with Your conclusions?
ReplyDeleteYou can not compare global trends regarding lightning with local ones. Not valid, since local forcing can vary. For example, much of our lightning is associated with COLD AIR ALOFT, which could well attenuate under global warming. Studies I have read show NO upward trend
DeleteThe recent thunderstorms have been the result of monsoon moisture, not cold air aloft.
DeleteMichael...it is more complex than you are suggesting. Thunderstorms required instability...which means a large lapse rate (change of temperature with height) and lift (often from an incoming trough). Cold air aloft is an essential contributor of many Northwest thunderstorms...cliff
DeleteI'm curious if you're tempted to write a post on the fires in Spain and France. I listen to the BBC where, to them, it is obvious that the fires are caused by global warming, because, as you know, fires are hot! What else could cause that!
ReplyDeleteThere are a lot of nay sayers to your points Cliff. Sorry for that. All they have to do is look at fire progression maps to realize your points are valid. Take Kaiser canyon, when it was in the low shrub of sage and grass it grew rapidly, when fire reached timber, guess what the progression has slowed. We have had wind events too once it reached timber, progression still was minimal compared to the sage and grass. Modrite fire, back into flashy fuels along the river. More growth from that than was when in just timber. With Saturdays wind events here, I do fear if it gets into thick unmanaged timber, crowning may occur and substatial growth may happen. That is another point to be made, while lighter substained winds can make grass shrub fires explode, takes a stronger wind event to carry fire into the crowns and substain a crown fire. Which i fear such an event may happen Saturday.
ReplyDeleteFingers crossed that Saturday's wind events don't materialize. The last thing Eastern Washington and Eastern Oregon need right now is for a crown fire to start.
DeleteWe currently have HUGE fires in E. WA (Ptarmigan @13,000+ acres, Little Giant @ 31,500+ acres, Sinlahekin @ 31,800+ acres, Kaiser Canyon at 134,000+ acres -all lightening caused - plus a few small ones down in grasslands). Wind will cause all these fires to ramp up and spread - that’s the big concern. As well as any new human caused fires, “crown” (trees), shrub steppe, wheat or grasslands!
DeleteThe "trend" shown on your charts is 1895-2025, not 1960-2025. If you take your 2nd chart (Division 6 temperature) and use a 1960-2025 trend, it's +0.5F per decade, not the +0.2F you mentioned. If you split it up, the trend from 1960-1995 is +0.0F, and the trend from 1996-2025 (the past 30 years) is +1.0F per decade. The trend for the past 20 years is +1.9F per decade. The trend for the past 10 years is +2.3F per decade.
ReplyDeleteThe trend is upwards, and accelerating. I'm curious why you would choose to use +0.2F for the analysis in this blog post. This is a genuine question, not any attempt at a "gotcha": Do you expect the trend to revert back to +0.2F per decade, and if so, why?
[I agree that the conditions this year have not been exceptional, at least not relative to anything in recent memory. So I'm not disputing your main point in this post.]
Very problematic to use short-term trends since natural variability can greatly influence them.
DeleteFor all the people who are sure that global warming is the cause of this year's fires, I can remember many years with lots of fires and very big fires. This year does not seem to be exceptional in any way. Fire is, and always has been, a natural event. Attributing this year's fires to unusual monsoon events, is also not reasonable. We have had monsoon events before. Global warming is surely happening. The facts are clear. Attributing local weather events to global warming is still a stretch. Focus on the facts.
ReplyDeleteThats exactly what the media does. They blame every extreme weather event on climate change which is outrageous and completely unscientific. News flash-Category 5 typhoons, heat domes bringing 100 plus degree temps, wildfires, and atmospheric rivers ALL existed far before humans existed and will still occur long after were gone.
DeleteExactly! These types of events need to be taken seriously, but to put the blame for them on climate change isn't appropriate. I saw one outlet (USA Today, if I recall correctly) earlier this week trying to claim that the 80 degree temperatures Seattle that is predicted to have and the 90 degree temperatures Portland is predicted to have next week were a result of the heat dome that is set to bake much of the Western United States. At this time of year, 80 degree temperatures in Seattle and 90 degree temperatures in Portland are not unusual. Blaming them on the heat dome struck me as being click-baity and unnecessarily alarmist.
DeleteI grew up in the Okanagan through the 90's and 2000's ... I notice less rain and lower elevation snow pack then there was then over the last decade. Maybe we're in a cycle, but every month has recorded below average precip going back awhile now, and above average temps more often than not. I don't even recall any smokey summers or fires prior to the big one in 2003, now it seems like every 2nd summer is prevalent smoke and fires.
ReplyDeleteI was just thinking about that as we currently suffer through consistent ( 24/7) smoke these past few days, Purple Air readings in the 200-300 range. It wasn’t like that in the 90’s, early 2000 until I think the Carlton Complex.
DeleteThere must have been years before the 90's where such conditions existed. They may not have occured as frequently as they do now, but Carlton Complex couldn't have been the start of 200-300 range air readings in our region.
DeleteI have lived in the Wenatchee area since 1964. There were definitely far fewer smoky summers until this century. A few of the bad fire years such as 1970 and 1994 had smoky periods when the large fires were burning but even in those years it was not a prolonged period of smoke as we have had in recent years. We did not usually have smoke blowing in from fires outside the Eastern Washington area either.
Deleteif you were older and you would speak otherwise....more fires and smoke in early 20th century...
DeleteCliff, those temperature plots clearly show a greater trend than +0.2F per decade. Division 6 is +0.5F per decade from 1960-present. The trend is +0.2F per decade from 1895-present which represents +2.6F of warming. Plus the last decade is well above the trend line which suggests acceleration of the linear trend.
ReplyDeleteJoe...as shown in the figure, the trend is for the entire record..since 1895.. It is not appropriate to look at the trend of the last decade. As you know, there are shorter-period modes of variability that make that a problem..cliff
DeleteCliff, while I acknowledge that there are short term weather trends on the one or two decade scale, you know as well as anyone that there are negative feedback loops associated with climate change. For this reason, it would be wise not to ignore a recent acceleration in the linear trend. This acceleration would possibly indicate that the negative feedback loops are starting to kick in. If this is the case, the accelerated rising temperature trend of the last decade is not just an anomaly but is in fact a warning at the worst is yet to come and downplaying the risk just gives cover for politicians to kick the can down the road and ignore taking action now.
DeleteRawley...there is no evidence that your suggestion is occurring....cliff
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