June Summary from Met Eireann

The Weather of June 2009: Warm and mainly wet; sunniest June for over 50 years in places 01 July 2009

There were warm and sunny conditions at times during June, but also spells of cool and unsettled weather, producing heavy rain at times. Very warm weather at the beginning and end of the month brought mean monthly air temperatures above normal everywhere, especially in western and southwestern areas. Mean monthly values were between one and two degrees above normal generally and it was the warmest June since 1970 at a number of stations.

However, temperatures fell significantly during the second week; after reaching around 25°C at the start of the month, the maximum temperature in Dublin was below 10°C on the 6th, a day of heavy rain and strong northeasterly winds. The maximum value of 9.4°C at Dublin (Phoenix Park) on this day was its lowest such value for June in well over a century of records at the station.

It was a relatively dry month in parts of the west and north, but rainfall totals were above normal at most stations. Much of the month’s rainfall was recorded on relatively few days, however; at Dublin Airport, for example, over 80% of the month’s total of 65mm was recorded on just two days. Most stations recorded between six and 12 wet days during the month (days with 1mm or more rainfall), compared with the normal range for June of between nine and 15. There were heavy daily falls in places on the 6th, 12th/13th, 16th/17th and 26th, with widespread thunderstorms at times; a tornado was reported near Castlerea, Co. Roscommon, on the 12th. A very localised thunderstorm in the Derrybeg area of County Donegal on the 23rd produced significant flooding in the area; estimated rainfall there of around 50mm within a 3-hour period would be expected to occur once every 100 years.

Sunshine totals were above normal everywhere and it was a particularly sunny month in the west and north, where some stations had their sunniest June since 1957. More than 15 hours of daily sunshine were widely recorded on one or more days in the period 1st to 4th.