Paul Homewood has an interesting post on the wet and windy spell of winter 1876/77, part of a series highlighting previous precedented periods of ‘unusual’ rainfall and storminess . Whilst reading the British Rainfall Publication for 1877 that he highlighted, I was struck by the similarity in the storm patterns, from the relentless succession of storms, gales and heavy rainfall to the short lulls between. This Times report from December 3 1876 notes how at one point during one storm “the mercury has fallen below 29 inches [982 mb] in all of the Kingdom”
So I wondered what the temperatures were like.
Temperature wise, 2013/4 was far less extreme with far less variability. From mid November until the beginning of March the mean values varied by only ~7 degrees Celsius compared to ~12 degrees for 1876/7.
It was whilst I was looking at the rainfall values I noted how remarkably close the two patterns were. Using the hydrological cycle (which runs from October) I added the values until the end of February, the last date for values this year.
1876/7 – 601.1
2013/4 – 691.9
So similar but this past winter is a fair bit higher with 90.8 mm more. This is how the values compare monthly
What is striking is the winter values almost seem to match, something I noticed more as I played with different visual charts excel has to offer. The two periods had near identical shapes but 1876 seemed to lag a month behind. The following is the two values, with the 1876 starting one month earlier as annotated in the chart below.
Over the ten month periods rainfall this year was greater by just 25.7mm (985.3-959.6mm) . Comparing the last four winter months of Oct-Jan 1876/7 and Nov-Feb 2013/14 the difference is just 16.4mm more for this year (539.9-523.5). 16.4mm is what often falls from the sky when a single low or front passes over.
To me this is suggestive of an unusually stuck, or blocked, jetstream pattern happening 137 years ago, long before carbon dioxide levels were a concern – indeed it was a couple of decades before Arrhenius started the carbon cycle of excuses. Our winter was unusual but it was not unprecedented. A quick search pulled up an interesting observation made in the Bighorn Mountains in Wyoming for the 6th January 1877
“Unusual heat followed by snow. In the evening there was snow and hail driven by a cruel wind.“
Back on the other side of the Atlantic, in Longthorns (Dorset?) a “severe thunderstorm” was reported “lasting 1 1/2 hours, with large hail.” From the early hours of the 7th an unstable system passed over the British isles hitting the West coast in the early hours before reaching Norfolk later that evening.
Hopefully I’ll be able to find further observations from both sides of the Atlantic.