Fire Season 2013Official OutlookBryan HenryMeteorologistNRCCAsh Creek2012
2012 1,497,9722006 1,201,1172007 1,185,1992000 1,087,9202003 942,0222008 241,8542001 223,3101999 218,1062011 198,6242005 185,4572002 172,1972010 70,4742009 69,0162004 40,840Median 220,708Average 523,865Recent History Shows…Data• Fire seasons across theNorthern Rockies Regionfall entirely into threecategories: Much AboveNormal, Normal, andBelow Normal• There is no “AboveNormal” category. Either~220,000 acres burn or amillion acres (+/-) burn.• Note the dramaticincrease in the number ofMuch Above Normal Yearssince 2000!!!!!!!!!!• It’s a new era.2013?Acres Burned
Fall Moisture andPreexisting DroughtConditionsWinterSnowpackMeltSpringFactorJulyTemperatures andPrecipitationLive/Dead FuelMoistureSummerConvectionOcean/AtmosphericCirculations(ENSO/PDO/etc.)Factors that Influence Fire Season SeveritySpring wasa “mixedbag” with awet finish.Fall was “near average”across the NR regionSnowpackis meltingat a fasterthan normalrate
Image 2 A: Fire sizes in relation to snow melt off date(basically, the earlier the melt off date, the larger the firestend to be). Image 2B: Number of large fires at mid elevations inrelation to snow melt off dates. (Basically, the earlier themelt off date, the more large fires that develop).*Note that the data only goes through 2002!
Effects of Climate Change on Numbersof Large FiresFigure 4a scatter plot ofannual number oflarge (> 200 ha) forestwildfires versus avgspring and summertemperature for theWestern USA USFS,Park Service, and BIAmanagement unitsreporting 1972 - 2004.Fires reported as ignitingin forested areasonly.Big Jump in #of large firesin years thatare .3 degreeswarmer thannormal.
This area is a former area ofmajor concern. However,significant precipitationreceived during May hasreduced concerns. With thatsaid, severe droughtconditions linger.Percent of Normal Precipitation (Last 30 days)Area ofMostConcernSome “ABOVENORMAL”potentialexists.
Model Precipitation Estimates Today through Friday
Map shows some recent improvement across SC and SEMT. SW MT still has some areas that are quite dry.
Thoughts on Fire Season2013 The Pburg fire at Discovery Ski Area was a falsestart. Normal start expected all locations. Drought across SW MT will persist and expand inareal coverage by early summer. Anticipate abnormally dry conditions across CentralID to develop into Moderate Drought by start of fireseason. Tropical forecasts and anticipated ridge positioningsuggest at least “normal” lightning activity again thisyear.
NormalNormalSee TextNormalAugust-SeptemberABOVE NORMALAUGUST THROUGHMID-SEPTEMBERText Some recent drought relief has occurred. However, alarge portion of SC MT remains under moderate tosevere drought. Area may become susceptible toABOVE NORMAL fire activity in August shouldabnormally warm and dry conditions develop.