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Joseph B. Pollina
,
Brian A. Colle
, and
Joseph J. Charney

1. Introduction a. Motivation Wildfires are an important forecast problem with significant societal impacts. Across the United States, ~4.7 million (~500 000) acres burn on average each year from wildfires west (east) of the Mississippi River (NIFC 2008 ). [This is equivalent to ~1.9 million (~202 430) ha, where 1 ha = 2.47 acre.] Wildfires in the northeast United States ( Fig. 1 ) have resulted in 13 633 acres burned on average annually, which is 0.27% of the total acres burned within the

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Christopher J. Schultz
,
Phillip M. Bitzer
,
Michael Antia
,
Jonathan L. Case
, and
Christopher R. Hain

1. Introduction Methods for prediction and identification of lightning-initiated wildfires (LIWs) were derived from laboratory and empirically generated analyses from the 1970s and 1990s ( Fuquay et al. 1979 ; Latham and Schlieter 1989 ; Meisner et al. 1993 ). LIWs are important to characterize because they account for over 56% of the acreage burned within the contiguous United States (CONUS) and over 84% of the land burned in Alaska ( Calef et al. 2017 ; Balch et al. 2017 ) and often

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Leanne Giordono
,
Muhammad Usman Amin Siddiqi
,
Greg Stelmach
,
Chad Zanocco
,
June Flora
, and
Hilary Boudet

1. Introduction The September 2020 Oregon wildfires were unprecedented with respect to both geographic scope and the number of communities affected by smoke and wildfire ( Schmidt et al. 2020 ). They resulted in widespread evacuation orders and prolonged poor air quality in Oregon’s most populous areas, nine deaths, and substantial property damage, including the destruction of over 4000 houses ( Oregon Office of Emergency Management 2021 ). While wildfires are not directly attributable to

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Neil P. Lareau
and
Craig B. Clements

1. Introduction Smoke dispersion is strongly affected by the structure and evolution of wildfire convective plumes. When wildfire plumes penetrate into the free troposphere they inject smoke aloft, causing regional- to global-scale impacts such as reduced insolation ( Penner et al. 1992 ) and modified cloud microphysics ( Andreae et al. 2004 ). On the other hand, when plumes remain confined within the atmospheric boundary layer, the smoke can more directly impact human populations, posing

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Jordan Richards
,
Raphaël Huser
,
Emanuele Bevacqua
, and
Jakob Zscheischler

1. Introduction With the frequency and severity of wildfires expected to be exasperated by climate change ( Di Virgilio et al. 2019 ; Dupuy et al. 2020 ; Jones et al. 2020 ; Ruffault et al. 2020 ; Ribeiro et al. 2022 ), many countries with Mediterranean climates now experience regularly occurring and devastating wildfires. The combined effect of extensive heatwaves and droughts in 2022 led to Europe observing its second-largest annual burnt area on record by 4 August ( Abnett 2022

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Clifford F. Mass
,
David Ovens
,
Robert Conrick
, and
John Saltenberger

1. Introduction On 7–8 September 2020, strong northerly/northeasterly winds, gusting to 40–70 kt (1 kt ≈ 0.51 m s −1 ) in exposed locations, pushed southward across eastern Washington and then westward across the Oregon Cascades, initiating and spreading multiple large fires in both states ( Fig. 1 ). In eastern Washington, the wildfires were mainly limited to grass and range vegetation within the Columbia basin, with total burned area reaching 529 000 acres. Less than 10% of the total burned

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Robert Conrick
,
Clifford F. Mass
,
Joseph P. Boomgard-Zagrodnik
, and
David Ovens

1. Introduction Wildfire smoke has many impacts on the meteorological environment. Through the aerosol direct effect, solar radiation is scattered by smoke particles which typically exhibit submicron sizes (e.g., Rissler et al. 2006 ). Such scattering of solar radiation reduces solar heating at the surface and results in a reduction in air temperatures in the lower troposphere, as described in several studies (e.g., Robock 1988 , 1991 ; Eck et al. 1998 ; Treffeisen et al. 2007 ; Stone et

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Taylor B. Aydell
and
Craig B. Clements

1. Introduction Wildfires are high-impact societal problems for the western United States and other fire-prone regions that can result in loss of life, property, and natural resources as well as degraded human health through the release of smoke and by-combustion products ( Dempsey 2013 ; McRae et al. 2015 ; Clements et al. 2018 ). Wildfires can cause regional- to global-scale impacts through smoke injection into the atmosphere such as reduced solar radiation ( Penner et al. 1992 ; Price et

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Piyush Jain
and
Mike Flannigan

ridging associated with drought events in California. Nakamura and Huang (2018) considered a mathematical analogy to traffic congestion to relate the onset of blocking with jet stream dynamics. Quinting and Vitart (2019) further explored the relationship of Rossby wave packets (RWPs) and blocking and found the decay of RWPs is associated with the onset of blocking in the European-Atlantic sector. a. Synoptic weather and wildfires At the landscape scale, wildland fire activity is determined by a

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Aseem R. Sharma
,
Piyush Jain
,
John T. Abatzoglou
, and
Mike Flannigan

, there exist ample studies that investigate the high pressure blocking ridges and their effects on surface variables such as temperature extremes ( Woollings et al. 2014 ; Whan et al. 2016 ), precipitation ( Antokhina et al. 2016 ), and heatwaves ( Rodrigues and Woolings 2017 ; Schaller et al. 2018 ). Synoptic-scale circulation patterns can similarly determine whether conditions are conducive for wildfire activity through their direct or indirect influence on fuel availability and moisture

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