As temperatures warm with the approach of summer in the Northern Hemisphere, another wildfire season is upon us. Time for a look at the forecast weather conditions and wildfire risk for the coming months.
Conditions in the U.S. going into this fire season are far different than they were this time last year. With a “mega drought” affecting much of the western U.S. in 2022, fears for a catastrophic wildfire season were high. However, a combination of some timely rainfall and overall favorable wind conditions resulted limited the wildfire damage to 7.5 million acres consumed — close to the decade average. New Mexico and Texas were hit particularly hard, with fires raging from the spring until the forecast summer monsoon rains came. Alaska also saw over three million acres burned. On the flip side, California had a relatively quiet fire season in 2022, with just 300,000 acres burned.
In December, an onslaught of winter storms began hitting the central California coast, with this pattern persisting through March. A huge amount of rain (and snow in mountains) fell across much of California. The winter storms continued across the Rockies into the northern Plains states, producing heavy snow. In April, the storm track shifted northward, with the Pacific Northwest getting the precipitation it had missed over the winter.
This precipitation has helped ease drought concerns. According to the U.S. Drought Monitor, 41 percent of California is now classified as in drought — compared to 100 percent at this point last year. While drought conditions have also improved over the northern Plains, they have spread and intensified in the central and southern Plains. Kansas has been hardest hit, with nearly 46 percent of the state (mostly in the west) now in “exceptional drought” — the highest classification. And in the east, the Florida peninsula has gone from the flooding rains of Hurricane Ian last fall, to drought this spring.
As of the end of April this year, there had been about 13,000 wildfires recorded across the U.S., with a total area burned of nearly 400,000 acres. Both figures are below normal for this time of year — particularly the acreage lost (although this varies greatly from year to year).
The weather outlook for the summer shows most of the country with above normal temperatures, with the exception of the northern Plains down to the Mid-Mississippi Valley, where average temperatures are predicted.
As for precipitation, wet conditions are forecast for the eastern third of the U.S., with normal rainfall in most of the rest of the lower 48 — except for below normal precipitation from Washington into the northern Rockies, and from New Mexico extending into western Texas. However, it’s worth keeping in mind that “normal” summer precipitation along the West Coast means dry conditions. Alaska is predicted to be warm, but with average rainfall to above average in the west. Tropical cyclone activity in the Atlantic and Gulf is currently forecast to be slightly below normal.
As a result of these forecast weather conditions, drought is predicted to persist from Kansas and eastern Colorado southward to eastern New Mexico through western Oklahoma, and though west Texas to the Mexican border. Drought conditions are expected to persist and expand somewhat in the interior of the Pacific Northwest and into northern Idaho and westernmost Montana. Drought conditions should improve in the northern Plains, Florida, and the eastern mid-Atlantic states.
The National Significant Wildland Fire Potential Outlook takes into consideration the forecast weather and drought conditions, but also where wildland fires normally occur during the summer — primarily forested regions. In June, the Upper Midwest is predicted to face “above normal” fire potential. The risk drops back to “normal” as summer starts.
As drought conditions intensify in the Pacific Northwest, the risk of wildfires becomes “above normal” in July and August. Wildfire risk in California is deemed as “below normal” at the start of the summer, but drops back to “normal” as typical summer dryness takes effect, with the exception of the still wet Sierra Mountains. Alaska is deemed as having “normal” risk throughout the summer.
The International Outlook
The 2022 wildfire season in Canada was relatively quiet, with a few exceptions. Nationwide, there were 5,700 fires recorded, which burned 1.6 million hectares (about four million acres). The Northwest Territories accounted for over 40 percent of the total area burned, while the Yukon saw 171,000 hectares (400,000 acres) burn last summer.
On the other side of the country, Newfoundland had one of its most severe wildfire seasons in recent history, with nearly 24,000 hectares (60,000 acres) burned. Conversely, British Columbia which has suffered extensive wildfire losses in recent years, had a relatively benign season.
As Canada enters its wildfire season, sections in the west from eastern British Columbia into southern Alberta and Saskatchewan are already in drought. Much of the eastern half of the country remains wet. As of May 1, there have been 574 fires, which have burned 5,144 hectares (12,711 acres). The number of fires is slightly above the 10-year average, but the area burned is well below the normal amount.
However, fire danger is already high in the drought-stricken parts of Alberta and Saskatchewan. And, on May 6, the Alberta government declared a provincial state of emergency due to out-of-control wildfires.
The extended weather forecast for the next three months is not encouraging. Temperatures throughout much of the country are predicted to be above normal, while almost all of central Canada is forecast to have below normal rainfall. The forecast for British Columbia shows below normal precipitation along the coast, but above normal in the mountainous eastern regions. In the east, Labrador should be dry, while Newfoundland is wet.
Putting together the predicted weather conditions and normal seasonal wildfire patterns, the official fire danger forecast for the summer shows the east will continue with low fire danger, but the situation in the west deteriorates further. By June, high fire danger is forecast in the three western provinces with some areas of “extreme” danger noted, including western British Columbia. In July, all of the southern portions of these provinces are forecast for “extreme” danger, and in August, wildfire conditions become even more acute with the dangerous conditions forecast to last into September.
Although wildfires were somewhat subdued in North America in 2022, this wasn’t the case in Europe. The 785,000 hectares (1.9 million acres) burned was a new record. The hottest summer in Europe’s recorded history brought heat waves and drought that fueled the fires. South and southwest France, northern Spain, and Portugal were especially hard hit in late July/early August.
The latest report from the European Drought Observatory indicated that “23 percent of the EU-27 territory is in drought warning conditions.” This includes much of Scandinavia, coastal areas along the Mediterranean Sea from Spain to Italy, and much of the area surrounding the Black Sea. And the long range weather outlook is for conditions to worsen.
Temperatures are forecast to be above normal throughout most of Europe this summer and even into the fall. Below normal rainfall begins to develop in June with negative anomalies intensifying in central Europe during July. Dryness continues into August, but is expected to abate in September.
For Australia, wildfire activity the last three years has been below normal, following the devastating wildfire season of 2019/20. Rains associated with a recurrent La Nina pattern have limited wildfire ignitions. However, one result of the abundant rainfall has been enhanced vegetation growth, providing potentially abundant fuel when dry conditions return. With an El Nino predicted to develop this year in the tropical Pacific, a return to a hot, dry summer — especially in the southern part of the country — could signal a reemergence of wildfire problems.
A recent study published in the Reviews of Geophysics suggests even worse wildfire conditions in the future with climate change. “The frequency and severity of fire weather has increased in recent decades and is projected to escalate with each added increment of warming,” warned the authors of the paper, “Global and Regional Trends and Drivers of Fire Under Climate Change.”
