From mid-December 2013 to early January, the UK experienced a spell of extreme weather as a succession of major winter storms brought widespread impacts to the UK (www.metoffice.gov.uk/climate/uk/interesting/2013-decwind).

Of particular interest the period 23-25 december 2013:

"The storm of 23 to 24 December brought particularly heavy rain to southern England and Wales, with a swathe from Dorset to Kent recording 50 to 70 mm, causing significant flooding problems. Rainfall totals for the 24 hours to 0900 UTC on 24th included 66.8 mm at Fontmell Magna (Dorset), 66.7 mm at Boscombe Down (Wiltshire), 61.0 mm at Mickleham (Surrey) and 63.2 mm at Wych Cross (East Sussex) - these totals being typically around three-quarters of the December average rainfall amount."

More here: sciencythoughts.blogspot.it/2013/12/at-l...-atlantic-storm.html

This event has been simulated on the DRIHM e-Infrastructure by the meteorological point of view (experiment suite 1) using the following steps for the WRF-ARW model:

a) the domains and the namelists have been prepared by means of the DRIHM portal, in particular two nested domains at 4 and 1.33 km have been defined



b) the initial and boundary conditions have been prepared on the CIMA DRIHM server using the WPS service there available and adopting IFS as global circulation model (initialization on 23 december 2013, 00UTC)

c) three different WRF microphysical schemes have been tested ranging from single to double moment schemes, namely

WSM6, Thompson and Morrison, for additional details see here

www2.mmm.ucar.edu/wrf/users/workshops/WS...s/Microphysics10.pdf

d) three simulations, corresponding to three different microphysical schemes, have been executed on the DRIHM e-Science environment resulting in very interesting and promising results.

In particular for all WRF settings, the 48 hours quantitative precipitation forecast (QPF, in mm) compares very well with the quantitative precipitation estimate derived from radar data (upper left panel in the following figure).

Dr. Alessandro Battaglia, University of Leicester,
www2.le.ac.uk/departments/physics/resear...alessandro-battaglia, has used some DRIHM outputs for the UK2013 DRIHM critical case to investigate the potential of a conically scanning cloud Doppler radar system.



Integrated total hydrometeor content [log10 - kg/m2] on the 23rd December at 12 UTC. The green
dotted line corresponds to the ground track of the satellite while the black (white) circles depict the
antenna boresight ground track for the low (high) altitude radar configuration in correspondence of
nine complete rotations. Outputs courtesy of FP7 DRIHM (www.drihm.eu) project.

More details at:

www.dropbox.com/s/qhc5cztvq9lltln/conica...r_Battaglia.pdf?dl=0