Summer 2019 - General Discussion

sryanbruen wrote: »

Top 5 coolest first halves to June on record (in terms of mean temperature) using the IMT.

1. 1972; 10.3c
2. 1987; 10.6c
3. 1991; 11.1c
4. 1977; 11.2c
5. 2015; 11.3c

2019 is running at 11.18c up to the 14th which is slightly under 1977.

*First half consists of the dates June 1st to 15th.

Data from Met Éireann.

Finished at a mean temperature of 11.14c making it the fourth coldest first half of June on record in Ireland back to 1967 using the IMT. Only 1972, 1987 and 1991 were colder.

eon1208 wrote: »

Sryan. What is IMT. What does the I stand for. Something mean temperature.

Irish Mean Temperature, MT uses it for his forecast contests.

Jpmarn wrote: »

Shannon Airport made to 18.8°c max yesterday Sunday 16. Is this the max temperature for Ireland this month so far?

20c at Phoenix Park and Newport.

Oneiric 3 wrote: »

Table showing stats for rainfall, max and min temps for June so far at all of the reporting Met Eireann stations.



Only Newport and Phoenix Park have manage to scrape a 20c so far, which is odd, considering both stations are on complete opposite ends of the country. Mean max temps are clearly running lower than normal, and averaged out on a nationwide scale, only come in at 14.7c, with is almost 2.0c below normal for the period (L.T.A is about 16.6c), and overall, is the coolest mean max for the first 2 weeks in June since 1987. Very wet also in most places, with Markee Castle and Ballyhaise in particular really up there.

Data from Met Eireann.

It has been one of the longest -NAO periods on record back to 1950 using CPC data with 53 days of -NAO up to June 16th and the longest such period since Summer 2012. Summer 2011 had the longest -NAO period on record with 68 -NAO days (a big reason why Summer 2011 was very cool and the coolest of the 21st century so far). Also important to note that Dec 2009/Jan 2010, Feb/Mar 2010 and Nov 2010-Jan 2011 fall in the top 10 record long -NAO periods according to the below figure.



Figure: Mika Rantanen.

Clearly the weather has been very different this June in Ireland to June 2018. Has the pattern been as much different as the weather? Yes, literally the polar opposite has happened (no pun intended). The two 500mb height anomalies below are of June 2018 and June 2019 (up to 14th) respectively.

In June 2018, there is a big area of above average heights parked right over Ireland with the North Atlantic jet stream way to the north bringing a very cool, wet and dull June to Iceland. Meanwhile, it was an exceptionally dry and warm month in Ireland.

In June 2019 so far, there has been extreme amounts of high latitude blocking (thus the -NAO). Equally, there's been a trough parked over Ireland (opposite to 2018) which has meant the cool and wet theme we've had.