Wettest May in history

It will come as no surprise to learn that May 2011 was the wettest ever May in more than 130 years of record keeping on the Isle of Lewis, with a total of more than 180mm (seven inches) of rain being recorded during the month in Stornoway.

Apart from an April hangover of three glorious days at the start of the month, it rained on every day of the month from the 4th onwards, finally ending up as wettest ever month of May since records began at Lews Castle, Stornoway in 1873.

Winds were often strong during the month, with frequent gales. A severe storm crossed southern Scotland on the 23rd – which was very unusual for May - with wind gusts reaching above 100mph in some locations, but Stornoway and the Hebrides escaped the worst.

One irony of the month were the widespread wildfires that broke out across the Western Highlands at the start of the month, following the dry warm weather at the end of April. The biggest fire was located north of Ullapool, near Inverkirkaig, smoke from which spread across the Minch to Stornoway on the 2nd

May 2010 Weather Statistics

Mean temperature: 9.8°C

Mean maximum temperature: 13.4°C (highest 19.7°C on 6th)

Mean minimum temperature: 6.5°C (lowest +2.7°C on 4th)

Precipitation: 188.4mm (7.42in, way above normal, about 250-300%)

Average humidity: 83.7%

There were 28 days with rain, 2 mornings with a grass frost, 1 day with snow/sleet falling and 2 days of hail falling.

*Readings and observations taken in Stornoway.

by Dr Edward Graham, Lews Castle College