...demons yelling, an immense eye darting fierce lightning all over the north of England, lightning which turns clerics into pitch, the sky becoming the colour of blood, oppressive heat which kills livestock and destroys crops, oppressive cold which kills livestock and destroys crops and nonstop rain for two years which kills livestock and destroys crops, so we advise remaining indoors for, ooooh, the next few decades. But don't worry! It's just God demonstrating his displeasure with the English for being wicked. Or possibly it's because Saturn is in the ascendant. The finest minds in England are still debating that one.
I've been toying for a while with the notion of writing a post on the weather of Edward II's era, and when I found this vivid and utterly brilliant description of a violent (and by the sounds of it, terrifying) thunderstorm recently in the Chronicle of Lanercost, I just had to post it here. The storm took place in the north of England during the night of 11/12 July 1293, when the future Edward II was nine:
"Early in the morning...we beheld in the east a huge cloud blacker than coal, in the midst whereof we saw the lashes of an immense eye darting fierce lightning into the west; whence I understood that Satan's darts would come from over the sea. Sure enough on the Sunday following, there began and continued throughout the night over the whole of the west part of the diocese of York, thunder and lightning so prodigious that the dazzling flashes followed each other without intermission, making, as it were, one continuous sunlight. Not only men were terrified and cried aloud, but even some domestic animals - horses, for certain. In some places houses were burnt or thrown down, and demons were heard yelling in the air."
Isn't the description of the yelling demons and the immense eye completely fantastic? And here's the same chronicle describing another thunderstorm, which damaged a church at Staveley near Chesterfield in Derbyshire on 29 September 1291: "suddenly, about the first hour of the day, the air became thick and dark, and by a single stroke of lightning much damage was caused all at once...it blackened all the right side of the image of the glorious Virgin over the altar, and did to death a certain cleric who was kneeling in prayer at the right end [of the altar], having there performed his mass, so suddenly that it turned that part of his body which was nearest the wall from head to foot, together with his garments, into something like pitch, the rest of him remaining entire...Such mysteries as these deserve to be shrewdly investigated at leisure and to be gravely considered."  (I have shrewdly investigated these mysteries, and gravely concluded that yelling demons were to blame.)
Anyway, here's a post about some weather conditions in England between 1305 and 1326 I've collected from various contemporary chronicles. It's notable that the English weather in the early fourteenth century was much more extreme then than it is these days, with lots of very cold winters and very hot summers, and the freakishly wet weather of the mid-1310s which caused the Great Famine.
The Flores Historiarum says that in the summer of 1305 - when the future Edward II was twenty-one and his father had two more years to live - England experienced "such a burning heat, and such a blight and drought throughout the summer, that the hay failed in most parts of the country, and the beasts of the field died for want, and a double heat (both while the sun was in Libra as well as he was in Leo) oppressed mankind. The consequence was, that small-pox and disease prostrated both children and young men, and rich and poor, and they were also afflicted with freckles and spots, and a great many young men and maidens died of the small-pox."
1305 was a year of extreme weather: this unusually hot summer was followed by "a winter of extreme cold, oppressing mankind much," with snow and ice on the ground from 15 December 1305 to 27 January 1306 and again from 13 February to 13 April 1306. "And the fish died in the ponds, and the birds in the woods, and the cattle in the fields. And many of the birds of heaven were so wasted away that they were caught without any net or snare by the hand of man." 
Bitterly cold winters were something of a feature of the early fourteenth century. The Croniques de London says that one year, presumably meaning the winter of 1307/1308 - the description of the weather follows the writer's statement that Piers Gaveston returned from exile and became earl of Cornwall, which happened in August 1307 - "there was such great ice on the Thames that many people went by foot on the ice to Southwark, and back to London." The winter of 1309/1310 saw the Great Frost, which the London annalist describes as follows: "There was such cold and such masses and piles of ice on the Thames and everywhere else that the poor were overcome by excessive cold," and adds that the river froze so solidly, bonfires could be lit on it. All the winters between 1312 and 1317 were also bitterly cold with much snow and frost, though on the other hand, some winters of the era were considerably less harsh: those of 1322/1323 and 1323/1324 were dry and mild, for example. 
The Sempringham continuator of the Livere de Reis de Brittanie, an enthusiastic recorder of the weather, says that there was a total eclipse of the sun on 1 February 1309 and "he had only half his light," though the writer claims, implausibly, that the eclipse lasted from midday until five in the afternoon. He also says that there was a total eclipse of the sun on 5 September 1290, and that the weather around the Feast of the Nativity of St John the Baptist that year - 24 June - was "rainy and cold," which will come as no surprise to anyone who's ever spent a June in England.  Off-topic but interesting here: a couple of weeks after the eclipse of 1309, a whale supposedly eighty feet long was caught in the Thames, to the great excitement of both the London and Pauline annalists.  In June 1315, Edward II gave a pound each to sailors named Thomas Springet, William Kempe and Edmund of Greenwich "for their labour in taking a whale, lately caught near London Bridge," which possibly was the same whale ('lately' in the fourteenth century could mean anything up to a few years). Also off-topic but interesting: the bishop of Nazareth was visiting England around the time of the total eclipse in 1309. 
According to the Livere de Reis, "thunders were heard, and there were sulphurous lightnings" on 24 October 1310. (But no immense eyes or yelling demons, sadly.) The first few months of 1312, when Piers Gaveston returned from his third exile, were dry and mild, and Lanercost says that on 5 July that year there was "an eclipse of the sun about the first hour of the day, and the sun appeared like a horned moon, which was small at first and then larger, until about the third hour it recovered its proper and usual size; though sometimes it seemed green, but sometimes of the colour which it usually has." There was a great storm in October 1313, and the following winter was another harsh one; spring came very late in 1314 after a bitterly cold April, and the beginning of that summer was also very cold. In fact, summer barely came at all in 1314, as by August, and maybe earlier, the endless rain which would destroy crops and lead to the Great Famine had started. It rained constantly for the rest of 1314, the misery only, one hopes, alleviated somewhat by a cold and frosty winter. 
1315 was also remarkably wet, even by English standards, and it rained more or less nonstop all year with the added bonus of gales in October. Edward II spent a month between mid-September and mid-October 1315 swimming and rowing in the Fens with "a great concourse of common people," intending to "refresh his soul with many waters," in the disapproving and sarcastic words of the Flores. Evidently the endless pouring rain and gales didn't put the hardy king off enjoying the great outdoors. The rain continued at least until the spring of 1316 and maybe later, at least in some parts of the country: some southern chroniclers report that the summer of 1316 was dry, though the chronicle Gesta Edwardi de Carnarvan, written at Bridlington in Yorkshire, says that it continued to be very wet. This probably represents a north-south divide in the weather, and at any rate, the endless rain had already wreaked its horrendous damage and at least five percent of the population of England died of starvation or associated disease.
Here's how the Vita Edwardi Secundi reported the awful weather:
"Alas, poor England! You who once helped other lands from your abundance, now poor and needy are forced to beg. Fruitful land is turned into a salt-marsh; the inclemency of the weather destroys the fatness of the land; corn is sown and tares are brought forth. All this comes from the wickedness of the inhabitants. Spare, O Lord, spare thy people! For we are a scorn and a derision to them who are round about us. Yet those who are wise in astrology say that these storms in the heavens have happened naturally; for Saturn, cold and heedless, brings rough weather that is useless to the seed; in the ascendant now for three years he has completed his course, and mild Jupiter duly succeeds him. Under Jupiter these floods of rain will cease, the valleys will grow rich with corn, and the fields filled with abundance." 
The winter of 1316/1317 was another very cold one, but thanks to Jupiter (!?) the summer of 1317 was - finally and no doubt to the huge relief of the long-suffering inhabitants of England - hot and dry. The Sempringham continuator of the Livere de Reis says, oddly, that in 1317 "there issued from the earth water-mice with long tails, larger than rats, with which the fields and meadows were filled in the summer and in August, also the towns and homesteads in the following winter." According to Lanercost, "before noon on the sixth day of September there was an eclipse of the sun." The Sempringham continuator went through a particularly enthusiastic phase in late 1319 and early 1320 of describing the weather conditions, so we know that:
- on 1 December 1319, "there was a general earthquake in England, with great sound and much noise."
- on the morning of 26 January 1320, there was a "wonderful eclipse of the moon of many various colours."
- and on 17 April 1320, "about midnight, there were frightful thunders heard, with lightning, and immoderately high wind." 
The winter of 1320/1321 was very wet and mild, with floods in the first few months of 1321; either these had receded by early May, when the Marcher lords and their allies began attacking the Welsh and English lands of the two Hugh Despensers, or the Marchers got very soggy. Winter 1321/1322 was yet another very harsh one: the Rochester chronicler says that snow lay on the ground for most of the first three months of 1322 and that the roads were hazardous, impeding Edward II’s progress through his kingdom on his campaign against the Marchers. A letter of Edward to all his sheriffs of 11 March 1322 says that he had been "unable to pass by the fords for several days by reason of the great flood in those parts," meaning the area around Tutbury and Burton-on-Trent in Staffordshire, and the Sempringham continuator, with his usual interest in the weather, says that the earl of Lancaster lost many supplies "through a great flood of water" when travelling from Pontefract to Tutbury on 1 March. Presumably a temporary thaw and a mass of melted snow caused the flooding. Presumably also, it subsequently froze again: when the earl of Lancaster was executed at Pontefract on 22 March, the Brut says that a crowd of onlookers "caste on hem meny balles of snowe." 
On 31 October 1322, both the Livere de Reis and the Brut observed an interesting phenomenon: the Livere says that the sky was "of a colour like blood" from Terce to Vespers, or nine a.m. to sunset, and the Brut says that the sun "turnede into blode, as the peple it saw. And that durede [lasted] fro the morne, til hit was xj of the Clokke of the day." Edward II then was in York, following his humiliating flight from the Scots at Rievaulx Abbey two weeks before, and I assume he must have seen it. For two chroniclers to record this, both naming the same day, implies that it was a widely-observed phenomenon. 
I can't find the reference now, but I seem to remember a statement in one chronicle - the Flores? - that sometime in 1322 or 1323 there was such torrential rain it was as though it was pouring out of a spout. It might have been the autumn of 1322 when Edward II was failing yet again on his latest Scottish campaign and the weather seems to have been pretty abysmal. October and November 1323 saw fine dry conditions, though, and generally speaking, mild and friendly weather prevailed during the last few years of Edward II's reign, although the spring of 1325 was very wet. During the summer of 1326, according to the Pauline annalist, England experienced another drought, and the Thames and other rivers receded alarmingly. This perhaps explains the entry in Edward II's chamber journal of 24 July 1326: the king gave sixpence to a Jack le Frenche of Walton, who "brought to the king by his command water from a well."  Edward was perhaps very thirsty in the heat!
I think what's especially fascinating isn't just the discovery that England 700 years ago had more extreme weather than it does these days, but the attitudes revealed by the chroniclers - the beliefs that a thunderstorm is the work of Satan and that years of awful weather and famine are either a) God punishing the English for being wicked or b) to be blamed on the movements of the planets. At any rate, I'll certainly be listening out for those yelling demons next time there's a thunderstorm.
1) The Chronicle of Lanercost 1272-1346, ed. Herbert Maxwell, pp. 82-83, 103.
2) The Flowers of History, ed. C. D. Yonge, vol. 2, p. 582.
3) Croniques de London depuis l'an 44 Hen III jusqu'à l'an 17 Edw III, ed. G. J. Aungier, p. 35; Annales Londonienses, in Chronicles of the Reigns of Edward I and Edward II, ed. W. Stubbs, vol. 1, p. 158; Annales Paulini in Ibid., p. 268; Derek Vincent Stern and Christopher Thornton, A Hertfordshire demesne of Westminster Abbey: profits, productivity and weather, pp. 98-99.
4) Le livere de reis de Brittanie e Le livere de reis de Engleterre, ed. J. Glover, pp. 325-327.
5) Annales Londonienses, p. 157; Annales Paulini, p. 267.
6) Frederick Devon, Issues of the Exchequer, p. 126; Annales Paulini, p. 266.
7) Livere de Reis, p. 329; Lanercost, p. 198; Stern and Thornton, Hertfordshire demesne, pp. 98-99.
8) Vita Edwardi Secundi, ed. N. Denholm-Young, p. 70.
9) Livere de Reis, pp. 333, 337; Lanercost, p. 218.
10) Historia Roffensis, folio 38v; Calendar of Close Rolls 1318-1323, p. 522; Livere de Reis, p. 341; The Brut or the Chronicles of England, ed. F. W. D. Brie, part 1, p. 223.
11) Brut, p. 228; Livere de Reis, p. 347.
12) Annales Paulini, pp. 312-313; Society of Antiquaries Library MS 122, p. 78.