Wednesday, June 1, 2016

Non-Threatening Wildfire Outlook

The National Interagency Fire Center in Boise released an updated national wildfire outlook today, and it contains a modest dose of good news for Alaska: the fire potential remains "normal" for the summer months throughout the entire state.  Last month's forecast had an elevated risk of fire in May for the south-central region, but no departure from normal is predicted for the rest of the season.

So far only 5700 acres have burned in Alaska this year, but of course significant fire activity doesn't usually kick in until June.  Last year the fire acreage was only 6400 acres on May 29, but the end of June and beginning of July were awful.  The record fire year of 2004 had even lower (almost zero) fire acreage at the beginning of June.  In contrast, 2014 was bad in May (almost 200,000 acres) but the rest of the season was quiet.

Here's the link to today's report:

The absence of an above-normal risk forecast seems a little surprising in view of the extremely warm spring experienced across Alaska together with the CPC forecast for continued abnormal warmth statewide this summer.  Perhaps the forecasters have taken note of the shift to a wetter pattern in May and, in the past couple of weeks, relatively cooler conditions as well.

Here are the temperature and precipitation anomalies for the April-May period at 16 long-term observing sites.  The area of each circle denotes the magnitude of the anomaly relative to the 1981-2010 distribution, in terms of standard deviations for temperature and percentile rank for precipitation.  If the colored circle is missing (as in some locations for precipitation), this indicates that conditions were close to normal.


  1. This year some fires are emerging from below. Not sure if or how that relates to this past year's climate. Any thoughts?


    1. Gary,

      The article says most of the 16 holdovers are on the Kenai Peninsula and Kodiak Island, which have been profoundly affected by the very warm ocean conditions - so this is suggestive of a link to the persistent warmth. But I'm not sure I can speculate beyond what the article says: "That big fire year [2015] combined with low snow last winter and a warm dry spring all may have combined to allow more holdovers."

    2. Mild dry winters (with low moisture content snow?) seem to contribute to holdover fires. I've watched them burn underground for weeks by consuming tree roots ignited by burn pile fires I started in mid-winter. Only by compressing the surface snow cover was I able to put them out by Spring. The compressed cover eliminated the insulation layer and melted enough water to quench them. They followed and burned along the tree roots that laid on mineral soil under 1-2' of forest duff.

      More info on 2016 risks: