TY - JOUR
T1 - Cloud Banding and Winds in Intense European Cyclones: Results from the DIAMET Project
AU - Vaughan, Geraint
AU - Methven, J.
AU - Anderson, D.
AU - Antonescu, B.
AU - Baker, L.
AU - Baker, T.P.
AU - Ballard, S.P.
AU - Bower, Keith
AU - Brown, P.R.A.
AU - Chagnon, J.
AU - Choularton, Thomas
AU - Chylik, J.
AU - Connolly, Paul
AU - Cook, P.A.
AU - Cotton, R.J.
AU - Crosier, Jonathan
AU - Dearden, Christopher
AU - Dorsey, James
AU - Frame, T.H.A.
AU - Gallagher, M.W.
AU - Goodliff, M.
AU - Gray, S.L.
AU - Harvey, B.J.
AU - Knippertz, P.
AU - Lean, H.W.
AU - Li, D.
AU - Lloyd, Gary
AU - MartÃnez-Alvarado, O.
AU - Nicol, J.
AU - Norris, Jesse
AU - Öström, E.
AU - Owen, J.
AU - Parker, D.J.
AU - Plant, R.S.
AU - Renfrew, I.A.
AU - Roberts, N.M.
AU - Rosenberg, P.
AU - Rudd, A.C.
AU - Schultz, David
AU - Taylor, J.P.
AU - Trzeciak, T.
AU - Tubbs, R.
AU - Vance, A.K.
AU - Van Leeuwen, P.J.
AU - Wellpott, A.
AU - Woolley, A.
N1 - DIAMET is funded by the Natural Environment Research Council (NERC) as part of the Storm Risk Mitigation Programme (Grant NE/I005234/1) in collaboration with the Met Office. The BAe 146 Atmospheric Research Aircraft is flown by Directflight Ltd. and managed by the Facility for Airborne Atmospheric Measurements (FAAM) on behalf of NERC and the Met Office. We particularly thank Captain Alan Foster and copilot Ian Ramsay-Rae for flying in such extreme conditions and working hard to find an airport that would let us land for refueling during the storm. Figure 3a was supplied by the Dundee Satellite Receiving Station. PK, JO, and TT received funding from the AXA Research Fund as part of the Seamless Approach to Assessing Model Uncertainties in Climate Projections of Severe European Windstorms (SEAMSEW) project.
PY - 2015/2
Y1 - 2015/2
N2 - The Diabatic Influences on Mesoscale Structures in Extratropical Storms (DIAMET) project aims to improve forecasts of high-impact weather in extratropical cyclones through field measurements, high-resolution numerical modeling, and improved design of ensemble forecasting and data assimilation systems. This article introduces DIAMET and presents some of the first results. Four field campaigns were conducted by the project, one of which, in late 2011, coincided with an exceptionally stormy period marked by an unusually strong, zonal North Atlantic jet stream and a succession of severe windstorms in northwest Europe. As a result, December 2011 had the highest monthly North Atlantic Oscillation index (2.52) of any December in the last 60 years. Detailed observations of several of these storms were gathered using the U.K.’s BAe 146 research aircraft and extensive ground-based measurements. As an example of the results obtained during the campaign, observations are presented of Extratropical Cyclone Friedhelm on 8 December 2011, when surface winds with gusts exceeding 30 m s–1 crossed central Scotland, leading to widespread disruption to transportation and electricity supply. Friedhelm deepened 44 hPa in 24 h and developed a pronounced bent-back front wrapping around the storm center. The strongest winds at 850 hPa and the surface occurred in the southern quadrant of the storm, and detailed measurements showed these to be most intense in clear air between bands of showers. High-resolution ensemble forecasts from the Met Office showed similar features, with the strongest winds aligned in linear swaths between the bands, suggesting that there is potential for improved skill in forecasts of damaging winds.
AB - The Diabatic Influences on Mesoscale Structures in Extratropical Storms (DIAMET) project aims to improve forecasts of high-impact weather in extratropical cyclones through field measurements, high-resolution numerical modeling, and improved design of ensemble forecasting and data assimilation systems. This article introduces DIAMET and presents some of the first results. Four field campaigns were conducted by the project, one of which, in late 2011, coincided with an exceptionally stormy period marked by an unusually strong, zonal North Atlantic jet stream and a succession of severe windstorms in northwest Europe. As a result, December 2011 had the highest monthly North Atlantic Oscillation index (2.52) of any December in the last 60 years. Detailed observations of several of these storms were gathered using the U.K.’s BAe 146 research aircraft and extensive ground-based measurements. As an example of the results obtained during the campaign, observations are presented of Extratropical Cyclone Friedhelm on 8 December 2011, when surface winds with gusts exceeding 30 m s–1 crossed central Scotland, leading to widespread disruption to transportation and electricity supply. Friedhelm deepened 44 hPa in 24 h and developed a pronounced bent-back front wrapping around the storm center. The strongest winds at 850 hPa and the surface occurred in the southern quadrant of the storm, and detailed measurements showed these to be most intense in clear air between bands of showers. High-resolution ensemble forecasts from the Met Office showed similar features, with the strongest winds aligned in linear swaths between the bands, suggesting that there is potential for improved skill in forecasts of damaging winds.
U2 - 10.1175/BAMS-D-13-00238.1
DO - 10.1175/BAMS-D-13-00238.1
M3 - Article
SN - 0003-0007
VL - 96
SP - 249
EP - 265
JO - American Meteorological Society. Bulletin
JF - American Meteorological Society. Bulletin
IS - 2
ER -
