Joint Centre for Mesoscale Meteorology (JCMM)
JCMM Internal Report No.81:A JCMM Overview of FASTEX IOPs by S A Clough, H W Lean, N M Roberts, H Birkett, J-P Chaboureau, R Dixon, M Griffiths, T D Hewson and A Montani
The Fronts and Atlantic Storm Track Experiment (FASTEX) took place through January and February 1997. The experiment had two principal objectives. The first was to observe the evolution of a group of cyclonic weather systems from the US Eastern seaboard across to the Eastern Atlantic and thus provide a test of methods of optimising forecasts by appropriate targeting of upstream observations. The second objective was to observe the mesoscale structure of oceanic weather systems in unprecedented detail by combined use of airborne Doppler radar and dropsonde observations. The experiment was particularly successful and resulted in observations of 20 weather events.
Given the difficulty of carrying out scientific studies of so many events, it was necessary to evaluate, compare and prioritise them. During Aril 1997 several JCMM members took part in an internal workshop to provide a timely evaluation of the Intensive Observing Periods (IOPs) from the point of view of JCMM's own scientific goals. This report summarises the main conclusions of the workshop regarding the evolution, distribution of observations and perceived scientific value of the individual cases. It includes brief summaries of observation distributions and tables comparing morphology, development, tropopause structure and diabatic process information for the systems observed. A fuller form also exists as a set of JCMM WWW pages (http://www.met.rdg.ac.uk/FASTEX), including animations of the events. The intention is not to give a comprehensive final account, but to give a brief account of the main aspects of the cases as an initial guide to further study.