NHESS Natural Hazards and Earth System Sciences NHESS Nat. Hazards Earth Syst. Sci. 1684-9981 Copernicus Publications Göttingen, Germany 10.5194/nhess-10-383-2010 Weather forecast in north-western Greece: RISKMED warnings and verification of MM5 model Bartzokas A. 1 Kotroni V. 2 Lagouvardos K. 2 Lolis C. J. 1 Gkikas A. 1 Tsirogianni M. I. 1 Laboratory of Meteorology, Department of Physics, University of Ioannina, Ioannina, Greece Institute of Environmental Research, National Observatory of Athens, Athens, Greece 25 02 2010 10 2 383 394 Copyright: © 2010 A. Bartzokas et al. 2010 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://nhess.copernicus.org/articles/10/383/2010/nhess-10-383-2010.html The full text article is available as a PDF file from https://nhess.copernicus.org/articles/10/383/2010/nhess-10-383-2010.pdf

The meteorological model MM5 is applied operationally for the area of north-western Greece for one-year period (1 June 2007–31 May 2008). The model output is used for daily weather forecasting over the area. An early warning system is developed, by dividing the study area in 16 sub-regions and defining specific thresholds for issuing alerts for adverse weather phenomena. The verification of the model is carried out by comparing the model results with observations from three automatic meteorological stations. For air temperature and wind speed, correlation coefficients and biases are calculated, revealing that there is a significant overestimation of the early morning air temperature. For precipitation amount, yes/no contingency tables are constructed for 4 specific thresholds and some categorical statistics are applied, showing that the prediction of precipitation in the area under study is generally satisfactory. Finally, the thunderstorm warnings issued by the system are verified against the observed lightning activity.

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