Chelan Complex

By the morning of August 14, 2015 it had not rained in Chelan for 73 days. When rain clouds last visited they imparted only a third of an inch, which promptly rejoined the atmosphere in the ambient temperatures spiking into the low 100’s. The lands around Chelan proper had not burned for ten to twelve years. Chelan is bounded by sagebrush steppe that fade into Ponderosa pine woodlands as one moves from the midlands toward the ridges that ring the Lake Chelan basin. The rangelands are populated by xeric plants, many of which follow a “boom and bust” strategy that allows them to take advantage of the meager precipitation in the early spring months before rapid and complete senescence.

Figure 1: Photo by King 5 News.

Exotic cheat grass blankets much of the hills, punctuated by wolf bunch grass specimens as domestic grazing is excluded from many parts of Chelan county. Forbs like arrowleaf balsamroot push out thick bunches of broad leaves on stout stems which after pollination dry to crackling tinder packets. Shrubs like big sagebrush, vine maple, and serviceberry are routinely broken by heavy snowfalls such that burgeoning growth is skirted by dead branches and litter. And tree specimens like Pondys shed lower limbs and crusts of bark as they age. So on the morning in question the hills around Chelan were draped in a decade’s worth of dry matter fuel loading primed by the heat of summer’s dog days.

Claps of thunder awoke many of us as a dry lightning storm advanced over the valley from the west. I watched tripartite lightning bolts connect with the Chelan Butte and return to sky, leaving glowing fingerprints where they had touched. As I watch the orange circles spread, I imagine how those spots were briefly hotter than the surface of the sun, something on the order of 36,000˚ F, before they cooled to a crisp 660˚ F as the surrounding vegetation warmed and combusted.

Figure 3: Photo by Kari Greer at Wildfire Today.

Officials reported later that lightning strikes started thousands of spot fires that morning and each of those fires were stoked by the hot winds that blow down the valley. After ignition, western winds from the foothills of the Cascades pushed the fires east toward the Columbia River. Gasses liberated by the intense flames turned the sun red as head flames pushed upslope and east. Four separate fire fronts, Chelan Butte, First Creek, Antione Creek, and Deer Mountain, eventually merged into the massive blaze dubbed the Chelan Complex.

Figure 4: Photo by David Ryder at Reuters.

The fire burned for some time, but not before it had consumed some 89,000 acres and caused an estimated $23 million in infrastructure damage.