Clodagh – The Storm That Was Not

By Paul Homewood 

   

http://blog.metoffice.gov.uk/2015/11/26/windy-but-storm-clodagh-looks-unlikely-this-weekend/

 

 

Last Thursday, the Met Office informed us that Storm Clodagh was unlikely.

Two days later, the Irish Met Office thought otherwise.

 

http://blog.metoffice.gov.uk/2015/11/28/met-eireann-names-storm-clodagh/

 

All a bit of a mess really.

But did Clodagh end up being a storm, or was it just another gale like Abigail and Barney?

Neil Catto provides the answer.  

 

 

Named Storms 3 Actual Storms 0

Storm Clodagh: 

On Saturday 28^th November 2015 the Met Office via the BBC reported the Irish Met Office (Met Eireann) had named the next winter storm Clodagh. Despite this cop out so they could blame someone else if a storm didn’t occur, regular weather forecasts by the BBC on behalf of the Met Office referred to Storm Clodagh. So what did happen? 

 

Fig 1 Met Eireann weather warning issued: Saturday 28Nov2015 18:00 – Valid: 28Nov2015 18:01 to 29Nov2015 15:00

 

Met Eireann in their warning state;

Southwesterly winds veering westerly will reach mean speeds og 60 to 80 kph, with gusts of 100 to 130 kph.

Clodagh, the third named storm of the extended winter season, will pass eastwards to the north of Ireland on Sunday morning 29^th November. The current Status Orange for very strong winds is a direct result of Clodagh’s evolution. Clodagh will pass through Scotland and the North Sea towards southern Scandinavia where it is expected to deepen further.

 

Fig 2 UKMO warnings: Issued at 12:20 on 29Nov2015 – Valid from 0700 on 29Nov2015 to 2000 on Sunday 29Nov2015

 

The UKMO does not mention Clodagh. Severe west to southwesterly gales are expected to affect England, Wales and parts of southern Scotland on Sunday. Inland gusts of 50-60 mph could occur, especially in the west and over northern England. Gusts around western coasts could reach 70 mph, this is most likely around coasts of north Wales, northwest England and Dumfries & Galloway.

As I captured this at 0641 on 29Nov2015 I guess their issue date should have been 28Nov2015 not the 29^th as stated.

Analysis of 80 UK weather reporting stations including four from Eire showed, none of the eighty stations reported a Force 10 storm.

 

Table 1 lowest pressure and highest sustained wind speeds obtained from hourly observations

 

The lowest pressure was in the Shetland Isles, but 972 mb is not particularly low for a winter storm. None of the highest wind speeds reached the 55 mph necessary to be classed as a STORM. The strongest winds were distributed over much of the country from Lydd (sustained 41 mph) in the southeast to Sumburgh in the North, Shannon (Ireland) in the West and Newcastle in the East. The UKMO excluded the middle part and northern Scotland in their warnings.

Conclusion: Apart from 3 hours at Benbecula during Storm Abigail, when technically it reached storm force 10 on the Beaufort scale, the rest of Abigail, Barney and now Clodagh DID NOT reach storm force at any of the 80 weather observing locations in the UK and Ireland.

What next; D – Deceptive, E – Elusive, F – Fart …..

FOOTNOTE

If you think Pembrey Sands sounds familiar, you would be right, as it appeared near the top of the list for “Storm” Barney.

A look at the location there shows why wind speeds will always be much higher there than elsewhere in the region. Effectively it is right on the beach, itself in a very exposed part of coastline. (The Met Office give an altitude of 3m).

As it is now an automatic station, any and every gust will be logged and relayed to the Met Office.