A couple of highlights from Matt Jolly’s fire weather presentation

fire danger firefighter entrapments
Association between weather and firefighter entrapments. From Matt Jolly presentation, May 2, 2019. Click to enlarge.

At the International Association of Wildland Fire’s Fuels conference currently underway in Albuquerque, Research Ecologist Matt Jolly’s presentation on “Mapping extreme fire weather and its impact on firefighter safety” was very interesting. In his allotted 20 minutes he began by talking about the rollout that is nearly complete of the third revision of the National Fire Danger Rating System.

Mr. Jolly described the development and evaluation of an extreme fire weather metric called the Severe Fire Weather Potential Index. The Index is strongly correlated to wildland fire occurrence and intensity detected by the MODIS satellite and is a strong predictor of wildland firefighter entrapments and fatalities from 1979 to 2017.

wildfiresafe app
WildfireSafe app. From Matt Jolly presentation, May 2, 2019.

Mr. Jolly said some firefighters have told him that the WildfireSafe app which has been in the prototype stage for the last three years is a useful tool for accurately predicting the fire danger at the local level.

These images were snapped with a cell phone during Mr. Jolly’s presentation.

Wildfire potential, May through August

If NIFC’s analysis is correct, wildfire activity along the west coast will grow substantially into the summer

wildfire potential

On May 1 the Predictive Services section at the National Interagency Fire Center issued their Wildland Fire Potential Outlook for May through August. The data represents the cumulative forecasts of the ten Geographic Area Predictive Services Units and the National Predictive Services Unit.

If NIFC’s analysis is correct, the wildfire potential in areas along the west coast will grow substantially into the summer.

The multi-year drought in California has been virtually neutralized due to substantial quantities of winter rain and snow. An area to watch will be the west sides of Oregon and Washington.

Below:

  • An excerpt from the NIFC narrative report for the next several months;
  • More of NIFC’s monthly graphical outlooks;
  • NOAA’s three-month temperature and precipitation forecasts; and,
  • Drought Monitor.

“Greenup is occurring across the nation entering May; fuels across the Southwest are now drying and curing and will become increasingly receptive to fire activity as the month progresses. Looking north, Alaska’s interior is becoming drier and increasing activity is expected. By late May and early June, California and the southern Great Basin will see an increase in activity as fine fuels dry and cure. In July, low and middle elevation fine fuels will dry across the remainder of the West and will gradually become receptive to fire activity from south to north. Unlike most years, there could be a delayed start to the season in the higher, timbered elevations due to preexisting weather conditions and slower than average snowpack melting rates. An exception to this could be along the Canadian Border with Washington, Idaho, and western Montana where below average snowpack and moderate drought conditions exist. These areas can expect an average start to the season with a potential for above normal activity. A normal transition out of fire season is expected across Alaska in July. The onset of the southwestern monsoon may be slightly delayed.

“August marks the beginning of the peak of the western fire season. Most of the country can expect Normal conditions. Exceptions will be along the West Coast. A heavy crop of grasses and fine fuels has developed across California and should elevate the potential as it cures and dries. Higher elevations in the Sierra will likely see a late entry into the season due to the record-setting snowpack and slow meltoff. The Pacific Northwest has entered a period of moderate drought. An early entry is possible across the Cascades and in the Okanogan. Elsewhere, some high elevations across the Great Basin and central Rockies could experience Below Normal potential and conditions.”

wildfire potential

Continue reading “Wildfire potential, May through August”

NWS develops system for quickly notifying land managers when satellites detect wildfires

The NWS may one day issue watches and warnings based on the predicted spread of a dangerous wildfire.

The higher resolution and shorter time intervals between images on the more recently launched weather satellites has made it a reality for wildfires to be detected and local land managers notified within minutes.

The new GOES 16 and GOES 17 satellites can identify new wildfire ignitions more accurately than their predecessors. The higher resolution means the location can sometimes be pinned down to within less than a miles as long as the temperature reaches the threshold that triggers the software to paint it in the image.

For a while the National Weather Service had occasionally notified land managers when they detected a wildfire but in 2016 as numerous blazes erupted in Oklahoma and Kansas the Oklahoma Forestry Services Fire Management Chief specifically asked for help to identify new fire starts. In an April 30, 2019 presentation  transmitted remotely to the International Association of Wildland Fire’s Fire Behavior and Fuels Conference in Albuquerque, T. Todd Lindley, Science and Operations Officer with the NWS, said that considering the fire storms brewing in the area on that day in 2016 that someone on their staff determined that, “We need to innovate today”.

detect wildfires satellite notify fire department
Cell phone photo of a slide from T. Todd Lindley’s remotely transmitted presentation April 30, 2019.

Within about four hours, Mr. Lindley said, they had developed a computer program that could enable a forecaster to send a notification to a land manager about a new fire very quickly, with just a few mouse clicks.

They have had success with the system, with 83 percent of notifications being received prior to local 911 calls.

And branching off of their ability to predict the tracks of thunderstorms and tornados and issuing watches and warnings, the NWS is experimenting with identifying the projected spread of a fire which could possibly lead to issuing watch and warning areas for wildfires.

Analysis of how precipitation affects wildfire occurrence

analysis precipitation wildfires

Researchers have developed a fancy graphic presentation that explores the relationship between precipitation and the annual area burned in the Western United States. You should check it out.

They concluded that weather conditions DURING the fire season, humidity and rain, have far more effect on total acres burned than winter snow.

The figures and text (below) here are excerpts from the document.


“Wildfires have been increasing: but why? Is it the effect of increasing temperatures? Declining snowpack? Decreasing precipitation? In their recent paper, “Decreasing fire season precipitation increased recent western US forest wildfire activity,” Zachary Holden and his co-authors explore the relative influence of these factors. They first identified the variables related to temperature, snow, and precipitation that best predicted area burned:

“Temperature: vapor pressure deficit [VPD] (the difference between the maximum amount of water the air can hold and the amount it actually holds)

“Snow: maximum annual snow water equivalent [SWE], and

“Precipitation: wetting rain days [WRD], days with more than 1/10 inch of rain, in the months of May through September.”

analysis precipitation wildfires

analysis precipitation wildfires

analysis precipitation wildfires

 

Wildfire potential, April through July

The outlook predicts above normal potential for western Washington and northwest Oregon

April 2019

On April 1 the Predictive Services section at the National Interagency Fire Center issued their Wildland Fire Potential Outlook for April through July. The data represents the cumulative forecasts of the ten Geographic Area Predictive Services Units and the National Predictive Services Unit.

If NIFC’s analysis is correct, western Washington and northwest Oregon should see above normal wildfire activity through mid-summer. In June wildfire potential should pick up in the coastal mountains of California while most of the Sierra Nevada Mountains are expected to have below normal activity during those two months.

Below:

  • An excerpt from the NIFC narrative report for the next several months;
  • More of NIFC’s monthly graphical outlooks;
  • NOAA’s three-month temperature and precipitation forecasts; and,
  • Drought Monitor.

“As the spring greenup begins to take hold across the West in April, mountain snowpack will begin to melt. Snowpack melting rates are a more important factor than snowpack levels in assessing potential fire season activity ahead. An average or slower than average melting rate can allow for a late entry of the timbered elevations into the fire season, whereas a faster melting rate will allow for high elevation fuels to become receptive to fire sooner. In 2019, an average to cooler than average spring is expected, so melting rates should be near average which could result in a delayed fire season entry in areas that have abundant snowpack. An early entry is possible along the Canadian border in areas that have a below average snowpack. In the middle and lower elevations, abundant winter and spring moisture should translate to a heavy crop of fine fuels that will become increasingly receptive to fire activity across the West from south to north in May, June, and July.

“In Alaska, warmer than average temperatures should lead to an early snowpack loss and early entry into the fire season. A possibility exists that precipitation could become above average from June onward. This could lessen some of the state’s peak season fire potential during the second half of the season. After an active early start to the season, fire activity across the state should trend toward average conditions. Hawaii and Puerto Rico will continue to see slightly elevated potential early in the outlook period until the impacts of tropical weather conditions begin to be felt. The Southwestern fire season should begin to end in early July as a below average and perhaps late monsoon arrives.”

May 2019
Continue reading “Wildfire potential, April through July”

Wildfire potential, March through June

If NIFC’s analysis is correct, wildfire activity should begin to increase in Eastern New Mexico and Western Texas in April.

wildfire potential fire danger outlook forecastOn March 1 the Predictive Services section at the National Interagency Fire Center issued their Wildland Fire Potential Outlook for March through June. The data represents the cumulative forecasts of the ten Geographic Area Predictive Services Units and the National Predictive Services Unit.

If NIFC’s analysis is correct, in April wildfire activity should begin to increase in Eastern New Mexico and Western Texas. In May it will transition to the greater Grand Canyon area, with much of California added in June.

Below:

  • An excerpt from the NIFC narrative report for the next several months;
  • More of NIFC’s monthly graphical outlooks;
  • NOAA’s three-month temperature and precipitation forecasts; and,
  • Drought Monitor.

The majority of the nation remained out of fire season in February. The minimal fire activity observed continued to be well below average nation-wide. What was observed was minimal and limited mainly to the western fringes of the Southern Area. While a weak El Niño persisted, resulting weather conditions were atypical to what is often observed during such events. Precipitation was generally near to above average in most locations except for two regions. The central and southern Great Plains were especially dry, and the Deep South had pockets of dry conditions as well. Portions of West Texas and eastern New Mexico received less than 5% of average precipitation. Overall, the Deep South fared better but portions of the Carolinas and the lower Mississippi River Valley recorded below average precipitation.

Temperatures were generally within about 3 degrees of average across the country. A slight cold bias existed in the West and across the northern tier. A slight warm bias existed across the South and Texas. Extreme departures from average were observed across the northern Great Plains where temperatures were as much as 25 degrees below average.

The frequency and strength of Pacific weather systems moving on shore and across the West allowed for above average precipitation to reduce the severity and scope of the ongoing drought across California and portions of Oregon and the Great Basin. Incredible amounts of snowfall intermittently shut down travel across the High Sierra in California. Soil moisture levels improved across most areas except western Oregon where the persistent dry conditions continued.

March is a transition month. Pregreenup grassfire activity is not uncommon along and east of the Rocky Mountain Front. At least average activity is expected until green up takes hold. Concerns decrease west of the Continental Divide where sustained periods of wet and cold conditions have persisted the past few months. As greenup takes hold in April, most areas experiencing preseason activity should begin to see a decrease except for the Southwest where the drying of fuels begins to show a gradual westward migration of fire activity.

Fire activity in May and June should increase in coverage and intensity across the Southwest and California. Some slight expansion of activity into the southern Great Basin is also expected. The above average precipitation received during the late winter and early spring months could translate to another above average grass crop that could prove to be problematic in June.

wildfire potential fire danger outlook forecast

Continue reading “Wildfire potential, March through June”