These initial maps use data available from about 180 observing sites available on 1 October 2008. They represent an initial assessment of the weather that was experienced across the UK during September 2008 and how it compares with the 1961 to 1990 average. On the ANOMALY maps red contours mark areas that are above average and blue contours mark areas that are below average.
| UK actual and anomaly maps | ||
|---|---|---|
| Maximum temperature | Actual max | Anomaly max |
| Minimum temperature | Actual min | Anomaly min |
| Mean temperature | Actual mean | Anomaly mean |
| Sunshine | Actual sunshine | Anomaly sunshine |
| Rainfall | Actual rainfall | Anomaly rainfall |
| Rainfall return period | Actual return period | |
| Days of rain with 1 mm or more | Actual days rain | Anomaly days rain |
| Lightning strikes | Actual lightning | |
| Grass minimum temperature | Actual grass | Anomaly grass |
| Days of grass frost | Actual grass frost | Anomaly grass frost |
| Days of air frost | Actual air frost | Anomaly air frost |
Note about rainfall return periods
Return periods relate to the named month only - to a first approximation you can divide by 12 to get the 'all months' return period. Rainfall amounts greater than average have positive return periods; amounts less than the average have negative return periods, e.g. a return period of -10 means that this is a dry event with a rainfall that is exceeded (in terms of dryness) on average once in 10 years.
