Adding to Fire Fighter Safety by Including Real-Time Radar Data in Short-Range Forecasts of Thunderstorm-Induced Wind Shifts

Gary L Achtemeier,Scott L Goodrick

doi:10.3390/fire4030055

Abstract

Abrupt changes in wind direction and speed caused by thunderstorm-generated gust fronts can, within a few seconds, transform slow-spreading low-intensity flanking fires into high-intensity head fires. Flame heights and spread rates can more than double. Fire mitigation strategies are challenged and the safety of fire crews is put at risk. We propose a class of numerical weather prediction models that incorporate real-time radar data and which can provide fire response units with images of accurate very short-range forecasts of gust front locations and intensities. Real-time weather radar data are coupled with a wind model that simulates density currents over complex terrain. Then two convective systems from formation and merger to gust front arrival at the location of a wildfire at Yarnell, Arizona, in 2013 are simulated. We present images of maps showing the progress of the gust fronts toward the fire. Such images can be transmitted to fire crews to assist decision-making. We conclude, therefore, that very short-range gust front prediction models that incorporate real-time radar data show promise as a means of predicting the critical weather information on gust front propagation for fire operations, and that such tools warrant further study.

Highlights

IntroductionOne tragic event occurred in 2013 at Yarnell Hill, Arizona, when a wind shift associated with thunderstorm outflows overran a wildfire changing its direction and rate of spread
Thunderstorm-generated gust fronts can pose a threat to the safety of fire crews [1].Sudden wind shifts have been implicated in a number of fire investigations over the years such as the Ransom Road Fire Report [2], the Dude Fire [3] and the Waldo Canyon Fire [4].One tragic event occurred in 2013 at Yarnell Hill, Arizona, when a wind shift associated with thunderstorm outflows overran a wildfire changing its direction and rate of spread
Initial thunderstorm development occurred along the Mogollon right of the figure

Summary

Introduction

One tragic event occurred in 2013 at Yarnell Hill, Arizona, when a wind shift associated with thunderstorm outflows overran a wildfire changing its direction and rate of spread. Predicting the approach of thunderstorm-related gust fronts, the timing of arrival, and the magnitude of outflow winds at a particular fire site, which may be located over a limited area within complex terrain, poses a challenging problem for fire weather forecasters. This situation often leaves response units and public safety officials unaware of the evolution of the fire environment

Results

Discussion

Conclusion