How accurate are we?

We have an open and transparent policy on how we verify the accuracy of our forecasts.

Forecast verification

Verification is needed to measure how we are doing against the Key Performance Targets (KPT) for forecast accuracy, as set by government. These KPTs are part of our ongoing long-term commitment to improving the accuracy of our forecasts to the public. We will do this by reaching accuracy targets set for:

• Probability of precipitation forecast, for the next day and the day after, for 139 places within the UK (Met Office observing sites).
• Temperature forecasts, for the next day and the day after, are assessed at the same sites as the probability of precipitation forecasts.
• The forecasting skill of our computer models

The following graphs show how we are doing against the Key Performance Targets.

UK computer model forecast accuracy

Global computer model forecast accuracy

UK temperature

UK rainfall

How we are doing

This table shows the Key Performance Targets for 2010/11.

Measure	Value at June 2010	Target for 2010/11	Achieved/ not achieved
UK Index	117.9	118.0	Assessed at end of March 2011
Global Index	139.3	141.7
UK Temperature Index	0.671	0.671
UK Precipitation Index	0.268	0.272

How we did last year

This table shows how we did against the Key Performance Targets for 2009/10.

Measure	Value at March 2010	Target for 2009/10	Achieved/ not achieved
UK Index	117.5	117.0	Achieved
Global Index	138.4	138.1	Achieved
UK Temperature Index	0.667	0.666	Achieved
UK Precipitation Index	0.270	0.267	Achieved