Comparison of Mobile-Radar Measurements of Tornado Intensity with Corresponding WSR-88D Measurements

Abstract

In the United States, visual observations of tornadoes and/or the existence of tornado damage currently provide the sole evidence of tornadogenesis in association with a mesocyclone or other radar-detected stormscale vortex. The severity of the tornado damage is currently the only means of estimating the intensity of tornadoes, radar detected or otherwise. The limitations of the damage-based record of tornado occurrence and intensity are well known and motivated this research. Weather Surveillance Radar-1988 Doppler (WSR-88D) measurements of the translating tornadic flow were compared with (semi-) coordinated measurements obtained near the surface with mobile radar. On the basis of a small yet fairly broad sample of tornadoes, high linear correlation was found between the vortex intensity (rotation plus translation) quantified using WSR-88D data and that quantified using Doppler on Wheels data. The possible effects of Doppler radar sampling on these results were explored through experiments with a simple vortex model. These experiments argued that the likelihood is high that a tornado would be sampled in a favorable way during at least one radar scan. Hence, the suggestion from this work is that WSR-88Ds (or similar operational radars) can potentially be used in isolation to estimate low-level tornado intensity. The proposed estimation is by way of a linear regression model, and application of this model is relevant only once a tornado is already confirmed.

Diagnosing the Conditional Probability of Tornado Damage Rating Using Environmental and Radar Attributes

“…Blair and Leighton (2014) noted the need for robust, scientific guidance for real-time tornado intensity estimates in their assessment of event confirmation in NWS warnings and statements across the central continental United States (CONUS) from 2007 to 2011. The early studies investigating the relationship between tornado intensity and radar (e.g., Kingfield et al 2012;LaDue et al 2012;Toth et al 2013) have shown some ability to identify different levels of tornado intensity in a diagnostic manner, thereby lending credence to the underlying idea of tornado intensity identification, from which IBW is based.…”

Finescale Radar Observations of Tornado and Mesocyclone Structures

“…''Big whirls have little whirls that feed on their velocity, and little whirls have lesser whirls and so on to viscosity'' (Richardson 1922). Since 1995, the Doppler On Wheels (DOW) mobile radars (Wurman et al 1997;Wurman 2001) have observed thousands of small-scale vortices in supercell thunderstorms, including more than 170 vortices categorized as distinct tornadoes (e.g., Wurman et al 1996a;Wurman and Gill 2000;Burgess et al 2002;Wurman 2005, 2008;Beck et al 2006;Dowell et al 2005;Kosiba et al 2008;Kosiba and Wurman 2010;Markowski et al 2011;Kosiba et al 2013;Toth et al 2013;Dowell et al 2002;Wurman et al 2007a;and Wurman and Kosiba 2008). Others also have documented several tornadoes and vortices using finescale radars (e.g., Bluestein and Pazmany 2000;Bluestein et al 1997Bluestein et al , 2003aBluestein et al ,b, 2004Bluestein et al , 2007bTanamachi et al 2007).…”

Doppler Radar Observations of a Wintertime Anticyclonic Misocyclone Associated with Surface Wind Gust on the Coast of the Sea of Japan

“…Therefore, there is no doubt that the damage was caused by the wind gust associated with the anticyclonic misocyclone; however, the structural relationship between the wind gust and misocyclone is not revealed because of the lack of radar data available for examining the low-level features. In addition to the under-or overestimation in the magnitudes (such as Vt and R), it should be noted that these values would be further affected by the position of the radar beam center relative to the exact center of the mesocyclone (e.g., Wood and Brown 1997;Burgess et al 2002;Toth et al 2013;French et al 2014). Since these values would fluctuate in the observation period and therefore those time variations would be quantitatively inaccurate, it is beyond the scope of this paper to investigate the time evolution of the misocyclone.…”