The Royal Charter storm . . . October 1859

The disaster . . .
 The fact that John Oram didn't make any note of what has become known as the 'Royal Charter Storm' is significant - because at the time, it was directly responsible for the loss of over 130 vessels around the coasts of Britain and a death toll (both sea-borne lives lost & deaths on land due falling masonry etc.) of around 800.

 In the case of the Royal Charter, which gave its name to the storm, over 450 of the passengers* and crew died. The ship ran aground on the north-east coast of Anglesey near the village of Moelfre (early hours 26th October, 1859). There then began a frantic & rather chaotic evacuation attempt, hampered by both the wild conditions and the blackness of the night. Before these efforts could achieve fruition, the vessel was pounded to destruction by stormy winds and giant waves - eventually breaking up by first-light that day (Figure 7); just 25-30 souls survived the disaster.
[* There is doubt about the exact figures as the passenger manifest was lost in the wreck.]

 All this happened after the ship had survived a voyage half-way around the world - and was near its destination port of Liverpool. It is almost certain that the captain sought shelter at this point (not far off his direct route into the port) from what had been strong-to-gale east or south-southeasterly winds, after the Liverpool Pilot had been unable to reach the Royal Charter: the Master no doubt assumed that a veer to a more southwesterly 'blow' would ensue and he would obtain a measure of shelter. But the nature of the storm meant that there was a rapid switch to a north or north-northeast wind, and more significantly a marked strengthening, with severe gusts, probably in the Force 11 or 12 category. The ship, even with engine assistance, was not able to manoeuvre sufficiently clear of the shore in the storm.

 The Royal Charter was one of a 'new breed' of ocean-going vessels - a sailing ship fitted with a coal-powered steam engine driving a screw-propeller. The ship was built on the Dee, Flintshire, for the Australian Steam Navigation Co., and launched in 1855. She was built for the Australia - England run and performed well in that capacity and when tragedy struck, the ship was at the end of a voyage from Melbourne to Liverpool that had been performed several times in her four years of life.
FitzRoy - and 'forecasting' . . .
 In 1854, Captain Robert FitzRoy RN was appointed as the Head of a new department of the Board of Trade [BoT], charged with the responsibility of collecting weather data from BoT registered ships putting in to UK ports. He had to coordinate the issue and calibration of equipment and arrange for standardised recording practices: there was no thought at this time of any 'forecasting' purpose to all this - for one very good reason that such reports were not received in 'real-time'.

  However, FitzRoy had throughout his career been interested in the prediction of weather events - principally by use of the barometer. He performed an analysis of the storm (Figure 8) using the data available to him - which became the basis for much work around that time by others, most notably in the United States and France. He became convinced that a system of warnings could be used and FitzRoy developed a theory of "forecasting the weather" using 15 coastal recording stations, the fledgling telegraph service and plotted charts. This system came into use in 1860 - the 'forecasts' being published in The Times. At the same time, the Board of Trade distributed 'storm glasses' to FitzRoy's design to some coastal communities around the kingdom.

 In 1861, the 'forecasting' system went one stage further with the establishment of a network of signal stations around the coast at major ports: if a gale was anticipated, a telegram was issued for the appropriate cones / barrels to be hoisted - this system lasted well into the latter half of the 20th century.

 All these developments are the forerunners of the work of the modern day Meteorological Office (now more simply Met Office).
The Storm . . .
 The origin of the storm is thought to have been well to the west of Portugal, possibly in the vicinity of the Azores (Booth, 1970; Lamb, 1991). The depression was first detected on the 24th near Cape Finisterre (NW Spain) and moved north-northeastwards to be in the western English Channel during the morning of the 25th and straddling Yorkshire / NE England 24 hours later (Figure 9).

 The airflow affecting much of Scotland and Ireland appears to have been ex-Arctic - the pattern having set in for several days past with inland frosts, snow and hail showers being reported: significant snowfall was recorded at high levels across Scotland, Ireland, northern England etc. on the day of the storm, emphasising the chill nature of the air-mass.

 In particular, our friend John Oram notes in his diary . . . snow on mountains on the 21st . . . heavy snow on the 22nd . . . snow on the 23rd and a dry but frosty period follows until 26 October, the day of the storm: this all ties in very well with an 'arctic' airmass intrusion that lasted several days. This was significant: in Oram's time in this part of Ireland, in 24 years of recording the weather, this was one of only two occasions with snow noted in October; the other was in 1880, his last full year in Mayo.

 The air mass in the 'warm sector' of the eventual storm, having come up from sub-tropical latitudes, was humid and warm: given the time of year and the subsequent development (heavy rain, around 25 mm in places, being reported), there must be a thought that some 'extra-tropical' elements were caught up in the circulation.

 The zone of strongest wind, estimated by FitzRoy to lie in the range 60 - 100 mph (Beaufort forces at least 10 / 'Storm', and perhaps up to force 12 / 'Hurricane-force') occupied a relatively narrow band, principally in the 'northerly' regime to the west or northwest of the low. This suggests that there was a 'squeeze' of gradient in this area, between the still vigorous area of low pressure (with its warm core) and the southward advection of cold air [leading to a rise in pressure] to its west. The thermal gradient would also be enhanced, along with associated developmental forcing. Add to that the fact that the seas would have been relatively warm (after the summer) with a cold 'polar' airmass running over the top, and the scene is set for significant convective pathways to the near-surface, allowing the full potential of the enhanced gradient flow to be realised in fearsome gusts.