The Relationship between Severe Weather Warnings, Storm Reports, and Storm Cell Frequency in and around Several Large Metropolitan Areas

Abstract

The spatial distribution of storm-based severe weather warnings, local storm reports, and radar-detected storm cells around six large cities in the central United States is examined from October 2007 to May 2017. The cities are Columbus, Ohio; Cincinnati, Ohio; Indianapolis, Indiana; Louisville, Kentucky; Nashville, Tennessee; and St. Louis, Missouri. In all six cities, warning counts within 20 km of the city center are found to vary by 20%–40%. In every city except St. Louis, a maximum in warnings is located 5–15 km to the east (downwind) of the city center. Additional analysis reveals that the location of the warning maxima often varies with wind direction. Areas of enhanced convective activity are also evident in and around each city. Many of these areas are found to the east of the city center and are coincident with areas of increased warnings. This alignment could suggest that urban influences are creating areas of enhanced severe weather potential on the eastern side of large cities. However, there are also instances where the locations of maxima in warnings, local storm reports, and convective activity are spatially offset. In these locations, it is possible that other factors are impacting the distribution of one or more of these fields.

Identifying Storm Hotspots and the Most Unsettled Areas in Barcelona by Analysing Significant Rainfall Episodes from 2013 to 2018

“…A study on regions in the United States by Naylor and Sexton [18] concluded that the urbanisation of metropolitan areas may have changed the location of convective storm cells and precipitation fields. In the Mediterranean region, there is a significant interaction between urbanisation and convective precipitation, as most floods are caused by very heavy and local precipitation in urbanised areas [7].…”

Variability in Isolated Convective Activity between Louisville, Kentucky, and Nearby Rural Locations

“…To identify instances of strong, isolated convective activity over Louisville, we create a ''cone of influence'' relative to a particular location using a process described in Naylor and Sexton (2018). This creates fanlike areas emanating from the reference location in either direction (Fig.…”

“…Several recent studies have focused specifically on the impact urban areas may have on strong, deep convection capable of producing severe weather. Naylor and Sexton (2018) found that storm-based National Weather Service warnings and the frequency of convective cells with a reflectivity of 50 dBZ or more are maximized on the downwind side of several large cities. Reames and Stensrud (2018) performed Weather Research and Forecasting (WRF) Model simulations of a supercell and found that the strength of low-level rotation, as well as the track of the near-surface mesocyclone, can be impacted by the presence of a large city.…”

Annual precipitation and daily extreme precipitation distribution: possible trends from 1960 to 2010 in urban areas of China

“…greenhouse gas emissions, anthropogenic heat, and urbanisation) have aroused more and more attentions (Karl & Trenberth 2003;Han et al 2014). Urban areas make the local weather and climate different from that in the surrounding suburbs (Naylor and Sexton 2018). In previous studies, the amount and frequency of precipitation tends to be higher in urban centers and downwind than in the surrounding areas (Ganeshan et al 2013;Zhang et al 2018).…”