Local and synoptic mechanisms causing Southern California’s Santa Ana winds

Hughes, Mimi; Hall, Alex

doi:10.1007/s00382-009-0650-4

Cited by 114 publications

(146 citation statements)

References 25 publications

Supporting

Mentioning

139

Contrasting

Order By: Relevance

“…We provide additional details of the physics parameterizations (e.g., boundary layer scheme, convection, ice microphysics, and cloud interactions) in the auxiliary material. Through comparison with point measurements, we have previously shown that the simulation reproduces local circulation statistics with a high degree of fidelity [Conil and Hall, 2006], including a specific validation of Santa Ana events [Hughes and Hall, 2010]. All major mountain complexes are represented in the weather simulation model (Figure 1), which is crucial for capturing wind corridors and meteorological patterns downwind of topography.…”

Section: Methodsmentioning

confidence: 91%

Spatial variation in extreme winds predicts large wildfire locations in chaparral ecosystems

Moritz

Moody

Krawchuk

et al. 2010

Geophysical Research Letters

Self Cite

132

133

View full text Add to dashboard Cite

[1] Fire plays a crucial role in many ecosystems, and a better understanding of different controls on fire activity is needed. Here we analyze spatial variation in fire danger during episodic wind events in coastal southern California, a densely populated Mediterranean-climate region. By reconstructing almost a decade of fire weather patterns through detailed simulations of Santa Ana winds, we produced the first high-resolution map of where these hot, dry winds are consistently most severe and which areas are relatively sheltered. We also analyzed over half a century of mapped fire history in chaparral ecosystems of the region, finding that our models successfully predict where the largest wildfires are most likely to occur. There is a surprising lack of information about extreme wind patterns worldwide, and more quantitative analyses of their spatial variation will be important for effective fire management and sustainable long-term urban development on fire-prone landscapes.

show abstract

Section: Methodsmentioning

confidence: 91%

Spatial variation in extreme winds predicts large wildfire locations in chaparral ecosystems

Moritz

Moody

Krawchuk

et al. 2010

Geophysical Research Letters

Self Cite

132

133

View full text Add to dashboard Cite

show abstract

“…Certain synoptic-scale conditions interacting with local topography contribute to Santa Ana occurrence (Yoshino 1975;Sommers 1978;Hughes and Hall 2010). This mid-February Santa Ana wind event commenced around 0000 UTC 15 February 2013, as maximum sea level pressures exceeded 1028 hPa in the Great Basin (Fig.…”

Section: The 14-16 February 2013 Event Observationsmentioning

confidence: 99%

“…Sommers 1978;Small 1995) that can produce gusts exceeding 45 m s 21 (100 mph) in favored areas. 1 The winds evince terrain-associated amplification of the mountain gap and downslope varieties (Huang et al 2009;Hughes and Hall 2010). Santa Ana events occur most frequently between October and February, with December being the peak month (Raphael 2003;Jones et al 2010).…”

Section: Introductionmentioning

confidence: 99%

Downslope Windstorms of San Diego County. Part I: A Case Study

Yang

Fovell

2016

Monthly Weather Review

View full text Add to dashboard Cite

The “Santa Ana” wind is an offshore flow that affects Southern California periodically during the winter half of the year, typically between September and May. The winds can be locally gusty, particularly in the complex terrain of San Diego County, where the winds have characteristics of downslope windstorms. These winds can cause and/or rapidly spread wildfires, the threat of which is particularly acute during the autumn season before the onset of winter rains. San Diego’s largest fires, including the Cedar fire of 2003 and Witch Creek fire of 2007, occurred during Santa Ana wind events. A case study of downslope flow during a moderately intense Santa Ana event during mid-February 2013 is presented. Motivated by the need to forecast winds impinging on electrical lines, the authors make use of an exceptionally dense network of near-surface observations in San Diego County to calibrate and verify simulations made utilizing the Advanced Research version of the Weather Research and Forecasting (WRF) Model, which in turn is employed to augment the observations. Results demonstrate that this particular Santa Ana episode consists of two pulses separated by a protracted lull. During the first pulse, the downslope flow is characterized by a prominent hydraulic jumplike feature, while during the second one the flow possesses a clear temporal progression of winds downslope. WRF has skill in capturing the evolution and magnitude of the event at most locations, although most model configurations overpredict the observed sustained wind and the forecast bias is itself biased.

show abstract

“…Despite the massive destruction wrought by the Diablo winds, associated with the Northern California firestorm of October 2017 and the Oakland Hills firestorm of 1991, very little is known quantitatively about them, especially relative to the Southern California downslope winds that favor wildfires, such as Santa Ana [1][2][3][4][5][6][7][8][9][10] and Sundowner [11][12][13][14][15] winds. A prescient preliminary analysis of 'Santa Ana-like' winds in the Oakland Hills was performed in 1973 [16], some 18 years prior to the Oakland Hills fire of 1991, and analyses [17][18][19] subsequent to that fire confirmed their localization at the eastern San Francisco Bay Area.…”

Section: Introductionmentioning

confidence: 99%

A Surface Observation Based Climatology of Diablo-Like Winds in California’s Wine Country and Western Sierra Nevada

Smith

Hatchett

Kaplan

2018

Fire

View full text Add to dashboard Cite

Diablo winds are dry and gusty north-northeasterly downslope windstorms that affect the San Francisco Bay Area in Northern California. On the evening of 8 October 2017, Diablo winds contributed to the ignitions and rapid spread of the "Northern California firestorm", including the Tubbs Fire, which burned 2800 homes in Santa Rosa, resulting in 22 fatalities and $1.2 B USD in damages. We analyzed 18 years of data from a network of surface meteorological stations and showed that Diablo winds tend to occur overnight through early morning in fall, winter and spring. In addition to the area north of the San Francisco Bay Area, conditions similar to Diablo winds commonly occur in the western Sierra Nevada. Both of these areas are characterized by high wind speeds and low relative humidity, but they neither tend to be warmer than climatology nor have a higher gust factor, or ratio of wind gusts to mean wind speeds, than climatology.

show abstract

Local and synoptic mechanisms causing Southern California’s Santa Ana winds

Abstract: The atmospheric conditions that

Cited by 114 publications

References 25 publications

Spatial variation in extreme winds predicts large wildfire locations in chaparral ecosystems

Spatial variation in extreme winds predicts large wildfire locations in chaparral ecosystems

Downslope Windstorms of San Diego County. Part I: A Case Study

A Surface Observation Based Climatology of Diablo-Like Winds in California’s Wine Country and Western Sierra Nevada

Contact Info

Product

Resources

About