Quasi-stationary Convective Storms in the UK: A Case Study. Robert Warren Supervised by Bob Plant, Humphrey Lean & Dan Kirshbaum. Background. Quasi-stationary convective storms (QSCSs) Repeated triggering and training of cells over a localised area for an extended period of time
Supervised by Bob Plant, Humphrey Lean & Dan Kirshbaum
Bottom line: land-sea temperature contrast was the primary control on the convergence line; land-sea roughness contrast, orography and cold pools all had only a minor influence.
Higher rain rates and a longer storm duration generated significantly higher accumulations and flash flooding in the Boscastle case. These differences were related to greater instability and column moisture, and a slower synoptic evolution.
A persistent, narrow convergence line, which appears to be a sea breeze front maintained in place by a slight offshore wind component (c.f. Golding et al. 2005).
Sudden veering of low-level wind ahead of an approaching surface trough.
Storms form too late and too far north along coast, and are too intense during late afternoon, but the overall accumulation pattern is captured fairly well.
500m run has significantly stronger convergence and thus triggers convection earlier, more in line with observations; however, still some issues with organisation and intensity of precipitation.