Accurate prediction of severe weather events is a key Met Office goal. As cyclonic systems are responsible for the vast majority of these events, accurate cyclone prediction is also high priority. Although huge strides have been made in numerical weather prediction (NWP) in recent years, cyclonic systems continue to pose problems for numerical models. Three 'exceptional' depressions in the Christmas periods of 1997 and 1999, and another in early December 1999 were all poorly forecast by most of the world's operational models, indicating that there is plenty of scope for improvement. The rationale for constructing a cyclone database (previously called the 'Frontal Wave Database') is described in detail in Hewson (1998b). The main motivation was the identification and representation of systematic model biases in new formats which, from most practical perspectives, represent a notable improvement on more traditional r.m.s. errorbased statistics. Several other possible uses have arisen in the intervening period; these are detailed at the end of this report. Evidently improved knowledge of cyclone forecast characteristics will be valuable not only to the NWP community, but also to forecasting, in part because operational practice now involves using 'Field Modification' software to prepare forecast charts (Carroll, 1997), which can be used to correct for known biases. The purpose of this report is to describe changes to the project since Hewson (1998b) (section 1.1), to outline the processing stages used to update the database (section 1.2), to describe database structure and list the current set of stored diagnostics (section 2), to pinpoint major problems encountered during the project (section 3), and indeed overall to provide sufficient information for interested parties to comprehend what the database includes and how it can be utilised. Figures from a limited initial analysis of the data are presented in section 4, followed by conclusions (section 5) and proposals describing the possible areas for future work (section 6).

{"references": ["Carroll, E.B., 1997. 'A technique for consistent alteration of NWP output fields'. Meteorol. Appl. 4. 171-178.", "Deveson, A.C.L., Browning, K.A., Hewson, T.D. 2001?. 'A Classification of FASTEX cyclones using a height attributable QG vertical motion diagnostic'. submitted to Q. J. R. Meteorol. Soc in Oct 2000.", "Deveson, A.C.L., 2000. 'The application of a height-attributable vertical motion diagnostic to the classification and evolution of extra-tropical cyclones'. PhD thesis, available from Dept. of Meteorology, University of Reading.", "Hewson, T.D. 1997. 'Objective identification of frontal wave cyclones' Meteorol. Appl. 4. 311-315.", "Hewson, T.D. 1998a. 'Objective fronts'. Meteorol. Appl. 5. 37-65.", "Hewson, T.D., 1998b. 'A Frontal Wave Database'. JCMM Internal Report No. 85. pp 20. Department of meteorology,", "Reading university.", "Hewson, T.D., 1999. 'Objective Identification of Fronts, Frontal Waves and Potential Waves'. A concluding report", "from the COST 78 project on Nowcasting. Proceedings of 4th European Conference on Applications of Meteorology, Norrkoping, Sweden, September 1999, pp.331-334.", "Hewson, T.D., 2001. 'The North Sea Storm of 30th October 2000'. Weather. To appear in March issue.", "Panagi, P. & Dicks, E. 1997. Met. Office Unified Model data, diagnostic graphics programs, and other observational", "data available from the JCMM through the aegis of the Universities Weather Research Network UWERN. JCMM", "internal report no 69. Department of meteorology, Reading university.", "Renfrew, I.A., Thorpe, A.J., and Bishop, C.H. 1997. The role of the environmental flow in the development of secondary frontal cyclones. Q. J .R. Meteorol. Soc. 123. 1653-167"]}

Previously curated at: http://cedadocs.ceda.ac.uk/361/ The publish date on this item was its original completed date. This work was funded by: Met Office. Associated projects: The Cyclone Database Project Main files in this record: CycloneDatabaseProjectReport.pdf Item originally deposited with Centre for Environmental Data Analysis (CEDA) document repository by Mr Tim D. Hewson. Transferred to CEDA document repository community on Zenodo on 2022-11-24