Forecasting the weather you want (to avoid)

  • June 2020
  • Meteorological Insight

There are various standard weather regime classifications which meteorologists have defined over time. A new approach is to define weather regimes according to an impact for a given end user of weather forecasts. Lake Street have taken as an example periods of dry weather in Oxfordshire, which is of importance for farmers, amongst others.

Whilst the first step is isolating weather regimes which deliver a given weather pattern (shown below), the second – arguably more important step – is establishing whether the weather regimes have predictive skill. If so, then often the numerical weather prediction models have better skill at forecasting the regimes than the implications, and so this approach can deliver improved forecast skill.

Four user defined regimes showing weather patterns which give dry spells for Oxfordshire
Figure 1: Four user defined regimes showing weather patterns which give dry spells for Oxfordshire

Alicia Gleeson gave a presentation about Lake Street work on user based regimes at the (virtual) Royal Meteorological Society early career scientist meeting at the end of June 2020.

The video of the presentation is available here with Alicia’s talk the last in that session, starting 1:10 in.