Northern Ireland Nearly Does It Again, Narrowly Misses April & June Record Lows

Written by Mark Vogan on June 9, 2015 in Rest of Europe, Spring 2015, Summer 2015, United Kingdom & Ireland with 0 Comments

Less than two months after Northern Ireland came within .5C of the all-time monthly minimum for April, Katesbridge, Co Down does it again this morning coming within .5C of the June record.

Thanks to the classic setup of clear skies and light winds, temperatures fell below freezing and fell to a minimum of -1.9C. Only thing is that it’s nearly mid June, summer nights are short and it’s not meant to be sub-freezing and frosty by now. We’re less than 2 weeks from the longest day of the year. The June record for Northern Ireland was -2.4C set back in 1991.

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In late April, a low of -8.1C was recorded at the same location. Why Katesbridge? Well blame the geography. Why so chilly? Blame the cold North Atlantic and a strong upper high positioned nearly directly overhead. But why a near winter-like -2C on June 9 when plenty of other times, high pressure provides very warm days in the 20s and those clear skies by night stay warm?

This high is unusually strong but more importantly it’s unusually cool and so days are pleasant under the powerful June sunshine but because the atmosphere is cooler than usual, caused by a colder than normal Atlantic underneath, surface warming by day is limited but by night, that air cools fast and to lower levels than normal because of colder air from above sinking to the ground by night.

Here’s the surface high.

Credit: AccuWeather Pro

850mb or 5,000ft level temps.

Credit: AccuWeather Pro

Expect further frosty and unusually cold nights away from major towns and cities as high pressure continues to dominate through ther next 72 hrs. Record lows are possible.

Wed AM

Credit: AccuWeather Pro

Thu AM

Credit: AccuWeather Pro

This near record cold in Northern Ireland and specifically, Katesbridge appears to be a trend because just last year, Katesbridge set a new August low for the whole of Northern Ireland. Ironically the new low for the month was -1.9C.

Stormy underneath the Atlantic to Russia ridge!

Meanwhile it’s rather stormy across Iberia, southern France into the Alps along the southern flank of this expansive west to east ridge that extends from well out into the Atlantic all the way to Asian Russia. Warm, humid air lifting north from the Med is bumping up against the boundary sparking major thunderstorm development with cloud tops soaring over 12 km into the atmosphere.

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The ridge weakens late week and drifts west out into the Atlantic allowing weather to push back into the UK from the south and north. I am watching the system gathering over Iberia as this may bring flooding rain potential into the Southern UK.