There are many weather forecasting services available for winter gritting forecasting, but one in particular stands out.
The importance of weather forecasting
Accurate weather forecasting is important because it protects life and property.
Forecasts based on temperature and rain are vital to farmers, temperature forecasts are critical for utilities and even on an everyday consumer basis, we all use use weather forecasts to determine what to wear on any given day.
Winter gritting forecasting is equally critical, especially to the transportation and logistics sector which has its busiest time - "peak" - in the three month period before Christmas when an unexpected frost or snowfall can bring Britain to a halt.
Road temperature forecasts
For millions of the U.K.'s commuters and the transportation sector then, what actually really matters is not just the temperature outside, but it's the temperature of the actual road.
Road temperature determines whether or not there's ice, and more important, black ice, and whether the nation's roads, car parks and footpaths are likely to be be treacherous.
With a health and safety obligation with punitive financial penalties to make sure that these have been made safe, road temperature also matters to the managers of the nation's business and industrial estates.
Regional winter gritting forecasting
That said, winter gritting forecasting also has to be accurate to the region - it's no good just taking the BBC's word for it that all of London will stay just above freezing.
Weather forecasting for London usually has a summary for the entire Greater London area, but everyone in the transportation sector knows that there are regional differences.
This is why a better winter gritting forecast uses regional cells, and can predict the weather accurately for each of those cells.
This is the model we use at GRITIT, thanks to the specialist winter transportation forecasts produced by the boffin teams at Metdesk, the world's premier sector-specific road temperature forecasters.
This means we're always sure when it's freezing in Fulham but only raining in Richmond.
Metdesk winter gritting forecasting
Metdesk holds itself to exceedingly stringent standards when it comes to its winter gritting forecasting.
Their winter gritting forecasts are measured against the following indicators and are based on forecasts and measurements at the road weather stations. All the figures are based on nights where the forecast of the observation was 5 degrees C or lower.
Bias: This is a measure of optimism/pessimism in the forecast model. This value will fluctuate based on the location of the weather station. For example, forecast sites in cold locations are more likely to have a neutral/positive bias whereas forecast sites in warm/intermediate locations will have a negative bias. There is no good or bad performance with this indicator but MetDesk overall (all forecast sites, all season) aims for a -0.25 degree bias. This is an indicator MetDesk uses internally to monitor the performance of the model.
RMSE (Root Mean Squared Error): This indicator provides a raw measure of accuracy irrespective of the zero line. The RMSE is the average difference between the forecast and observation. For example, a forecast of +1 and an observation of -1 is a net difference of 2 degrees. This is the RMSE.
The RMSE fluctuates from site to site. Cold sites are more predictable and you therefore expect the forecast performance to be better. Sites located in frost hollows are more difficult to forecast for and this is where you are most likely to see a worse RMSE performance. MetDesk aims for an average RMSE of <1.5 degrees over the course of the entire winter. The RMSE is optimised daily by MetDesk and subject to model intervention by the forecasters should a location consistently exhibit a high RMSE.
%Correct: This is probably the most often quoted indicator and shows the % of forecasts and observations within the critical night range which were the same side of zero. Unlike the RMSE value, this indicator does not provide a measure of forecast accuracy.
False Alarm Rate: The percentage of forecasts where a frost was forecast but no frost observed
Miss Rate: The percentage of forecasts where no frost was forecast but a frost was observed
Under these indicators, Metdesk consistently scores a higher rate than rival winter gritting forecasters, which is why it is GRITIT's winter gritting forecaster of choice.
GRITIT & Metdesk
GRITIT's service is the perfect companion to the premium winter forecasting service in the U.K.
Our model revolves around an agreed activation temperature: if it freezes, we're on it, 24/7, 365/365, under a pre-agreed full coverage service that means there there are no limits to the amount of times that we'll make sure that your assets are gritted and safe for the entire season, with an added indemnity cover to take all the risk off you and onto us.