The Forecaster Working Group: Forecasts during SOP and tasks for the future

During the preparatory phase for the Special Observing Period (SOP) the forecasters working group participated in an intense discussion process and training exercise in forecasting techniques in mountainous terrain. One of the preliminary results is a checklist of forecast criteria which has been worked out by specialists with in-depth regional synoptic experience. An important contribution to the development of a new forecasting system was the definition of the special NWP output, in particular the selection and the unification of the meteorological parameters and their contouring.

During the SOP the forecasters provided highly specialized forecasts of different time scales to support the research teams in their decision making. To be able to do so, a strong co-operation has been established. A meteorological discussion between forecasters of different weather services and of different nations was started. The results of this very dynamic development should now be of use for the meteorological services in terms of synoptic education and training, critique and development of NWP models and optimization of forecasting tools. All this implies a continuation of the strengthened interaction between operational forecasters and the atmospheric scientific community.

Targets dedicated to MAP

Ensure availability of MAP (SOP)-data: The good connections within the forecasters of all Alpine countries could be used to facilitate or to accelerate the exchange of meteorological data.

Forecasting skill during the MAP SOP: An important task of this group is to try to quantify the skill of the forecasts produced during MAP-SOP taking in particular account the frequency of false alarms. Some false alarms could be selected as case studies; similarly for events which occurred but were not predicted.

Targets for the future

Forecast-training for mountainous terrain: At many national and regional weather services a lot of rules and tools for specific forecasts have been developed, which should be exchanged and discussed in an international forum for the benefit of all participants.

Develop mesoscale conceptual models: Due to the increasing need for specialized and automatically produced forecasts, objective, high resolution both in space and time, forecast methods for mountainous terrain become more and more necessary.

Support to model development: For the MAP SOP a common visualization scheme for the output of different NWP was created. This powerful system used in operational forecasting enables multi-lateral critique and therefore enhanced models development.

Figure 2. Summary of forecast reports produced during the Special Observing Period. The acronyms denote respectively: HP heavy precipitation, SF south Foehn, PV potential vorticity, GWB gravity wave breaking, IOP number of Intensive Observing Period. The forecasts for a date are in one line, starting with the forecast made at the same day (day 1) and ending with the forecast made 3 days before (day 4). Probabilities: NIL (0), POSSIBLE (1), LIKELY (2), CERTAIN (3), empty cells: phenomenon not mentioned.