Convective‐scale numerical weather prediction and warnings over Lake Victoria: Part II —Can model output support severe weather warning decision‐making?
Year: 2022
Type: article
Abstract: The greater Lake Victoria region was the focus of the ‘HIGHWeather impact lAke sYstem’ project, with the aim of developing an early warning capability for hazardous weather. Strong thunderstorm outflows can cause boats to capsize and lead to drowning. Lightning is also a hazard to fishermen, and over land flash flooding from heavy rainfall is a significant hazard. Between March and October 2019, 16 regional warnings were issued, and 14 days had reported impacts. Only one of the issued warnings aligned with any reported impacts. The issued warnings were verified using three different methodologies and found to have a very low frequency bias, confirming that too few warnings are being issued, especially for precipitation. The skill of the warnings based on the probability of detection and symmetric extremal dependency index was also found to be low. Potential warnings days are derived from individual and multivariate combinations of numerical weather prediction forecasts of mean wind speed, precipitation and a new lightning diagnostic from the 4.4 km Tropical Africa configuration of the Met Office Unified Model. The methodology identified 5–7 times the issued number of warnings, including 50% of days with reported impacts and 25% of days with issued warnings. Overall, 70%–80% of the identified potential warning days appear to be justified, suggesting that for this period not enough warnings were issued. It is shown that a daily aggregate of the lightning diagnostic is a skilful addition to any guidance supporting a decision‐making process.
Source: Meteorological Applications
DOI: 10.1002/met.2055
Institutions: Met Office, South African Weather Service
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Climate action
Open Access status: gold
Estimated APC paid: $2,400
Awards: THIS PROPOSAL OFFERS TO SUPPORT THE NASA EARTH SCIENCE RESEARCH DIVISION AND THE AEG WITH PROGRAM AND PROJECT PLANNING; SCIENTIFIC TECHNICAL AND ENGINEERING ANALYSIS; PANEL AND PAPER REVIEWS; INTERAGENCY (NASA NOAA NSF) UNIVERSITY AND INTERNATIONAL (E.G. WMO EUMETSAT JMA KMA CMA INPE) MISSION AND RESEARCH PROJECT COORDINATION AND DATA ARCHIVE/DATA PORTAL ACCESS THE NASA GLOBAL HYDROLOGY RESOURCE CENTER DISTRIBUTED ACTIVE ARCHIVE CENTER GHRC DAAC) AND USE FOR RECENT (2017 GOES-R FIELD CAMPAIGN) AND PLANNED 2018-2019 EXPERIMENTS (RELAMPAGO/NSF LAKE VICTORIA HIGHWAY/WMO SEVERE AND HIGH IMPACT WEATHER STUDIES/NASA). EACH OF THESE PROJECTS USES SPACEBASED OBSERVATIONS - FROM GEOSTATIONARY AND LOW EARTH ORBIT THE ISS-LIS INSTRUMENTED AIRPLANES RESEARCH AND OPERATIONAL SATELLITES AND GROUND-BASED OBSERVING NETWORKS COMPLEMENTED WITH ANCILLARY DATA WHERE ALL ARE KEY COMPONENTS OF THE RESEARCH ANALYSIS., G2951889612
OpenAlex ID: W4280583243