A High-Resolution Numerical Weather Prediction system for Greece: Model Setup and Performance Analysis

Περίληψη

The Laboratory of Meteorology and Climatology (http://meteo.geo.auth.gr) of the Aristotle University of Thessaloniki utilizes the non-hydrostatic Weather Research and Forecasting model with the Advanced Research dynamic solver (WRF-ARW) in order to produce 4-day operational weather forecasts. Three model domains, using 2-way telescoping nesting, cover: i) Europe, the Mediterranean sea and northern Africa, ii) Greece and iii) the wider region of Macedonia - Thermaikos Gulf at horizontal grid-spacings of 15km, 5km and 1.667km, respectively. In the framework of WaveForUs project (http://wave4us.web.auth.gr), the WRF-ARW forecasts are employed (offline) by the partners in storm surge, wave and coastal circulation models in order to produce high-resolution operational sea-state forecasts for Thermaikos Gulf. The meteorological and sea-state forecasts are disseminated to end users and the public. The aim of this paper is to describe the  meteorological model setup and analyse its performance during the first year of the operational period of the WaveForUs project (June 2013 – May 2014). The statistical scores were computed at different forecast times as a function of the season and the prevailing upper-air synoptic circulation in Greece. This methodology allows the identification of model errors that occur at specific periods and/or synoptic conditions and may otherwise be obscured in aggregate statistics. In general, the maximum errors were associated with cut-off and closed lows while the most predictable conditions occurred in anticyclonic/omega blocking circulations and in summer season.