THE FRONTS AND ATLANTIC STORM-TRACK EXPERIMENT (FASTEX) - SCIENTIFIC OBJECTIVES AND EXPERIMENTAL-DESIGN

The Fronts and Atlantic Storm-Track Experiment (FASTEX) will address t he life cycle of cyclones evolving over the North Atlantic Ocean in Ja nuary and February 1997. The objectives of FASTEX are to improve the f orecasts of end-of-storm-track cyclogenesis (primarily in the eastern Atlantic but with applicability to the Pacific) in the range 24 to 72 h, to enable the testing of theoretical ideas on cyclone formation and development, and to document the vertical and the mesoscale structure of cloud systems in mature cyclones and their relation to the dynamic s. The observing system includes ships that will remain in the vicinit y of the main baroclinic zone in the central Atlantic Ocean, jet aircr aft that will fly and drop sondes off the east coast of North America or over the central Atlantic Ocean, turboprop aircraft that will surve y mature cyclones off Ireland with dropsondes, and airborne Doppler ra dars, including ASTRAIA/ELDORA. Radiosounding frequency around the Nor th Atlantic basin will be increased, as well as the number of drifting buoys. These facilities will be activated during multiple-day intensi ve observing periods in order to observe the same meteorological syste ms at several stages of their life cycle. A central archive will be de veloped in quasi-real time in Toulouse, France, thus allowing data to be made widely available to the scientific community.