May 23 - July 29
Assessing the Impact of Vulnerability Knowledge on NWS Forecasters and Tornado Emergency Issuance
Kelsey Othling (Louisiana State University), Dr. Michelle Saunders (OU/CASR), and Dr. Jack Friedman (OU/CASR)
What is already known:
- Traditionally, meteorologists rely on their experience with past severe weather events to know where vulnerabilities exist and whether to issue a severe warning
- The Brief Vulnerability Overview Tool (BVOT) is composed of a shapefile showing known vulnerabilities that can be integrated into NWS’s AWIPS to highlight specific spatial vulnerabilities.
- The BVOT has been shown to improve spatial situational awareness for weather forecasting offices (WFOs) and messaging to core partners
- While operational meteorologists receive guidance for issuing tornado warnings and emergencies, what knowledge of vulnerabilities meteorologists have and how they draw on and reliably use this knowledge when issuing tornado warning and emergencies remains under-examined
What this study adds:
- The BVOT improves frequency and context of messaging within formal NWS warnings and messaging to core partners
- The BVOT increases spatial situational awareness of NWS forecasters, especially when used by backup WFOs and newer forecasters
- Storm reports and tornado confirmation are a major factor in forecasters’ decisions to upgrade traditional warnings to a Particularly Dangerous Situation (PDS) or a tornado emergency
- Many forecasters are hesitant to issue tornado emergencies due to lack of prior experience issuing them, uncertainty in issuance thresholds, and perceived negative public reaction
Abstract:
The topic of tornado emergencies has not been studied extensively, especially regarding the deciding factors for issuance, perception by forecasters, and effectiveness in reducing tornado mortality compared to traditional warnings. Accessible knowledge of an area’s hazard-specific vulnerabilities is critical to making accurate and efficient decisions during impactful severe weather events. This study assesses the Brief Vulnerability Overview Tool (BVOT) which has been shown to improve spatial situational awareness for weather forecasting offices (WFOs) and messaging to core partners. This paper is a novel exploration of the decision-making that goes behind forecasters issuing tornado emergencies, specifically looking at if access to the BVOT played a role. It also assesses the impact a forecaster’s background may have on messaging and decision-making within a WFO. Data were collected using an online qualitative software to selectively code for patterns and themes found within transcripts of a severe weather event simulation. This study finds that NWS forecasters report that the BVOT increases the frequency and context of their messaging and improves spatial awareness to an area’s associated vulnerabilities. During the test case—March 25, 2021—all forecasters, regardless of experimental condition, upgraded base warnings to a Particularly Dangerous Situation (PDS) while some forecaster teams that had BVOT issued a tornado emergency. However, many forecasters were hesitant to issue tornado emergencies due to lack of prior experience issuing them, uncertainty in issuance thresholds, and perceived negative public reaction.