This article presents a 13‐year hail climatology for Switzerland based on volumetric radar reflectivity. Two radar‐based detection products that are used operationally at MeteoSwiss, namely the Probability of Hail (POH) and Maximum Expected Severe Size (MESHS), have been reprocessed extended convective season (April–September) between 2002 2014. The result these two is comprehensive distribution map, which highlights regional local‐scale characteristics. map annual number days shows high...

In this study, we present a unique 15‐year hail streak climatology for Switzerland based on volumetric radar reflectivity. Two radar‐based detection products and an automatic thunderstorm‐tracking algorithm were reprocessed the extended convective season (April–September) between 2002 2016. More than 1.1 million cells automatically tracked over full domain, 191,000 storms 31,000 streaks in considered subdomain selected analysis following consistency robustness tests. The year‐to‐year...

Abstract Nowcasting of hailstorms still poses a major challenge to weather services, because the limited availability reliable large datasets and short spatio‐temporal scales involved. Two novel Eulerian Lagrangian hail climatologies for Alps are applied address important aspects in Alps: diurnal cycle, their development lightning properties. The database contains more than 100,000 ordinary 30,000 storms (2002–2017). Based on that sample storms, cycle storm initiation evolution is studied...

© 2018 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).CORRESPONDING AUTHOR: Olivia Martius, olivia.martius@giub.unibe.ch

Abstract Hail is the costliest atmospheric hazard in Switzerland, causing substantial damage to agriculture, cars and buildings every year. In this study, a 12‐year statistic of objectively identified cold fronts radar‐based hail are combined investigate co‐occurrence Switzerland. first step, an automated front identification scheme, which has previously been designed for applied global reanalysis data, modified high‐resolution regional analysis data set. This detection method then adapted,...

The purpose of the operationally oriented system named Context and Scale Oriented Thunderstorm Satellite Predictors Development (COALITION) is automatically to detect severe thunderstorms early in their development consequently help weather forecasters increase lead times when issuing warnings. This new object‐oriented integrates data provided by different sources. Data from Meteosat Second Generation Rapid Scan Service, radar numerical prediction, as well climatology, are utilized system....

Abstract. We present a feasibility study for an object-based method to characterise thunderstorm properties in simulation data from convection-permitting weather models. An existing tracker, the Thunderstorm Identification, Tracking, Analysis and Nowcasting (TITAN) algorithm, was applied thunderstorms simulated by Advanced Research Weather Forecasting (AR-WRF) model at resolution domain centred on Switzerland. Three WRF microphysics parameterisations were tested. The results are compared...

The 1 st European Hail workshop took place in Bern June 2014.The was organized into five topical session i) Convection and hail a changing climate, ii) Microphysics dynamics of hailstorms, iii) damage prevention, iv) Local probabilities long-term statistics hail, v) Nowcasting forecasting hail.This report summarizes the scientific contributions presented open questions discussed at workshop.

Abstract. In Switzerland, hail regularly occurs in multi-day clusters. The atmospheric conditions prior to and during clusters are described contrasted the isolated days. analysis focuses on days that occurred between April September 2002–2019 within 140 km of Swiss radar network. Hail north south Alps defined using a minimum area threshold radar-based product. Multi-day as 5 d windows containing 4 or single day. reanalysis ERA-5 is used study large-scale flow combination with objectively...

Severe weather events are constantly increasing over northern Italy impacting the air traffic of one major airports Europe: Milano Malpensa. Monitoring and predicting extreme convection is very challenging especially when it develops locally in a short time range. This work performed within two projects funded by H2020 SESAR Programme, with objective nowcasting high accuracy strong affecting airport. We collected different types data from 10 locations around airport developed an end-to-end...

Abstract. In Switzerland, hail regularly occurs in multi-day clusters. The atmospheric conditions prior to and during clusters are described contrasted the isolated days. analysis focuses on days that occurred between April September 2002–2019 within 140 km of Swiss radar network. Hail north south Alps defined using a minimum area threshold radar-based product. Multi-day as 5-day windows containing 4 or 5 single day. reanalysis ERA-5 is used study large-scale flow combination with...

Blitzschlagbrände und Sommertrockenheit: Gibt es einen Zusammenhang? Blitzschläge sind weltweit die wichtigste natürliche Ursache für Waldbrände. In der Schweiz machen im Schnitt rund Drittel (30.5%) Hochsommer (Juni, Juli August) vorkommenden Brandereignisse aus. diesem Beitrag analysieren wir das Auftreten herrschenden meteorologischen Bedingungen, welche 275 in Waldbranddatenbank «Swissfire» Periode 2000–2018 registrierten charakterisieren. fast ausschliesslich gebirgigen Lagen zu...

Abstract. We present a feasibility study for an object-based method to characterise thunderstorm properties in simulation data from convection-permitting weather models. An existing tracker, the Thunderstorm Identification, Tracking, Analysis and Nowcasting (TITAN) algorithm, was applied thunderstorms simulated by Advanced Research Weather Forecasting (AR-WRF) model at resolution domain centred on Switzerland. Three WRF microphysics parameterisations were tested. The results are compared...