Even in the twenty‐first century forecasting the weather can be challenging, while public expectations of accuracy are high. However, for the UK public at least, complaining about terrible weather or the inaccuracy of forecasts does provide a familiar topic of conversation. Weather forecasts are now well‐established as part of the daily news cycle. It is also well known that they began, along with modern meteorology, in the nineteenth century, and that daily forecasts first appeared in The Times (of London) in August 1861. The term itself was created by one of the founders of this new type of weather prediction, Robert FitzRoy, who strongly believed that forecasts should be published as a public service – even if it led to ridicule for him, personally. Following his appointment as Superintendent of the Meteorological Department of the Board of Trade in 1854, FitzRoy established 15 coastal observation stations, and was able also to use the new technology of the telegraph to make the reception and collation of weather observations very much faster (Eden, 2009). It was in October 1860 that he received the first such telegraph from the Valentia Observatory on the southwest coast of Ireland, and from 1861 until his death in 1865 he made it his responsibility to issue not only reports but also warnings of impending weather. FitzRoy's intention in coining the new term was to make it clear that his ‘forecasts’ used a scientific procedure, based on reliable data collection, and had nothing to do with the ‘prognostications’ then published annually in cheap almanacs.

These almanacs were issued by astrologers and were increasingly derided by 1800. They have also been excluded from histories of early modern meteorology on the grounds that they were not based on scholastic commentaries on Aristotle's work (Martin, 2011). However, some authors made ‘modern’ arguments for their long‐established methods. A very popular title was Vox Stellarum, which was issued by the Stationers' Company from 1700 and continued to be credited to Francis Moore throughout much of the nineteenth century (making his appellation of ‘Old Moore’ very appropriate). By 1804, the author was already competing with newer methods of predicting the weather and was proudly quoting monthly measurements of rainfall in the previous year, ‘taken at the Royal Society's House in London’. The number of places for which monthly measurements of rainfall were given grew considerably over the next decades, and attention was also given to atmospheric pressure. The compiler combined the analysis of these data with his astrological prognostications, to produce brave predictions of the timing and quantity of rainfall. He urged that if ‘journals of the weather’ were kept across the kingdom, and published annually, ‘this in Time would tend to bring Meteorology to greater Perfection’. By 1848, his readers were also urged to use a barometer, in order to increase meteorological knowledge and prove the efficacy of traditional prognostication. Hindsight makes it clear that it was FitzRoy's approach that deservedly prevailed; but attempts to combine scientific method and astrological belief have a very long, and influential, history (Figure 1).

Medieval astronomers/astrologers already produced forecasts using both detailed observations of actual weather and complex astronomical and mathematical calculations. My research (Lawrence‐Mathers, 2019) has shown that these methods were taken seriously from the ninth to the eighteenth centuries. In the sixteenth and seventeenth centuries, the astronomers Tycho Brahe and Johannes Kepler still made forecasts of this sort and still recommended the collection of data to improve accuracy. The scientific theory involved started with classical astronomy, which espoused the idea that celestial bodies – especially planets – exerted powerful forces over the Earth and its inhabitants. Each planet was believed to have a specific set of qualities and powers, which affected related phenomena on Earth. Exactly how this worked was elaborated by natural philosophers in the Islamicate world, drawing upon the work of classical Greek, Hellenistic, Persian and Indian authorities. The Aristotelian model of the universe, with the Earth stationary at its centre, was accepted almost universally, even though some Arabian astronomers posited that the Earth rotated on its axis, and others took up suggestions that Mercury and Venus actually orbited around the Sun (Figure 2).

Islamicate scientists hypothesised that the Earth was surrounded by spheres composed of the four classical elements (earth, water, air and fire), which were in turn surrounded by the spheres within which the planets were carried. Both the planets and the stars emitted rays that reached the Earth's surface, and which interacted with one another and with the elemental spheres en route.

Perhaps most influential were the arguments of the great philosopher‐scientist, Al‐Kindi (c. 800–870 ce) (Burnett, 2004). He accepted the theory that the movements of the celestial bodies generated heat, which in turn created movement and change in the atmospheric zone around the Earth. In addition, he argued that it was the effects of the planetary rays that determined in detail how meteorological phenomena would fluctuate on Earth. The qualities and elemental affinities attributed to each planet since Antiquity were accepted, so that Saturn, for instance, was especially associated with the element of earth, and was dry and cold. Its rays would thus carry these attributes. Most powerful in this system were the Sun and the Moon, whose effects on phenomena such as season, climate, daylight, tides and (allegedly) bodily fluids and plant growth were known to all educated individuals. These greater luminaries were powerful enough to have major effects on the rays of the other planets but could in turn be affected when other planets were in influential positions in relation to them (Figure 3).

This theory had already been given mathematical and geometrical precision by Claudius Ptolemy of Alexandria, the great geographer, cosmologist and astronomer of the second century. Ptolemy's main contribution was to produce complex models that made it possible to predict with considerable accuracy where the planets would be on any chosen date (Almagest, Ptolemy, 1998 edn). This in turn meant, as Ptolemy said, that it was possible to calculate how their effects would interact, and what the outcome would be for the Earth's atmosphere and weather. Ptolemy outlined how detailed weather forecasts could be made, through interpreting the calculated positions of all the significant celestial bodies on the chosen date, in relation to one another and to a specified point on the Earth's surface (Tetrabiblos, Ptolemy, 1940 edn). The standard method for recording the positions was in degrees and minutes of longitude on the ecliptic, described in terms of the 12 equal divisions of the circle of the zodiac. This was important because these divisions (known as houses or signs) had characteristics largely determined by the stars in or close to them, and these would affect nearby planets (Figure 4).

To quantify the interactions between planets, it was also necessary to note the angular relationships between the houses they occupied, and whether they were moving towards or away from one another. The latter was especially important when considering interactions involving the powerful and fast‐moving Moon. Ptolemy's summary of the theory was: ‘It is clear that when the planets are in significant associations with one another they produce very many variations in the quality of our atmosphere, with the intrinsic power of each remaining but being modified in its strength by the forces of the bodies with which it is configured’ (Tetrabiblos, p. 45). Thus, an apparently simple model could generate a relatively large quantity of data when it came to producing an actual forecast.

Philosopher‐scientists in the Arab Empire from the ninth century onwards compiled new data into updated planetary tables and refined Ptolemy's methods of weather forecasting. Their work was slowly assimilated by scholars in Europe from the late eleventh century and incorporated into university teaching of astronomy by the thirteenth century. The main barrier to wider, successful forecasting was the complexity of the calculations involved, but advances in mathematics and the adoption of Hindu–Arabic numerals helped to overcome this. Also important was the rise of acclaimed experts in the new ‘science of the stars’ who achieved fame for successful predictions and forecasts and rose to influential positions in both political centres and universities. The spread of Latin translations made Al‐Kindi one such expert, and his overview of how the atmosphere and the weather worked, and the causes of heat and cold, drought and rain, and wind remained influential well into the sixteenth century. He was unusual in challenging Aristotle's views on some of these phenomena, and particularly on the winds. Whilst ‘the Philosopher’ related the winds to ‘exhalations’ occurring above and below the surface of the Earth, Al‐Kindi preferred heat as the fundamental driving force. He stated that the joint influence of the Sun and Moon determined the level of heat in the air of a particular region, and that heated air would rapidly expand into a zone where cooler air had contracted, thus determining the strength and direction of the wind (Lawrence‐Mathers, 2019, pp. 82–84) (Figure 5).

One of the most popular Latin treatises on weather forecasting was attributed to Robert Grosseteste, the thirteenth‐century scientist and bishop of Lincoln. This offered a simplified method of making the forecasts and urged that forewarning of droughts or floods would save many lives. Later, some practitioners achieved great fame for their forecasts. The Oxford astronomer/astrologer, John of Eschenden, was praised for having predicted the great plague of 1348/1349, though his prediction was in fact rather vague. His on‐going prognostications of prolonged cold, wet and windy weather, causing floods and famines into the 1370s, were also acclaimed as correct. It should be noted that the concept of planetary influence on material phenomena, including the atmosphere and its movements, raised no theological problems for the medieval Church. Meteorological study and weather prognostication were entirely acceptable areas of study (Figure 6).

The serious work going into weather forecasting in the late Middle Ages is further shown by the growing practice of making detailed observations of weather and correlating them with forecasts. The earliest known examples of this come from England and Germany. Perhaps, earliest of all are the weather notes entered into the margins of a calendar for 1269/1270, found in a collection of the works of Roger Bacon, which was put together in Oxford in the late thirteenth century. A full translation was published (in Weather, 29(6) (Long, 1974)) and the juxtaposition was then seen as puzzling. In the light of Bacon's arguments that astronomers, like all other scientists, should put their models ‘to the test of experience’ in order to improve their utility, the concept of comparing planetary positions with actual weather seems consistent with Bacon's drive to establish the sciences (including what would now be classed as astrology) as of fundamental value for society (Figure 7).

Similar work was taken seriously in the fourteenth century, as is shown by the weather observations compiled and studied alongside planetary data in Oxford, Lincoln, Wurzburg and (possibly) Basel. Records for 1337–1344 accompany the ‘Rules’ for weather forecasting issued by Master William de Merle, who was linked to Merton College, Oxford, and to William Reed (bishop of Chichester, 1369–1385) [Symons, 1891]. In the Basel manuscript, records of weather in the years 1399–1406 are found with notes on astrometeorological factors that possibly correlated with them. For instance, 7 April 1400 was cloudy, with short sunny intervals and a strong West wind. It is noted that the Moon moved away from the beneficent planet, Jupiter, and out of an Air sign, whilst approaching Mercury, known to cause disturbance in the air. The effect of such empirical study, however surprisingly, was to increase confidence in astronomically based weather forecasting. Arguably, the idea that the route to reliable forecasts was via the collection of records, analysed alongside meteorological models, was a major legacy of medieval science in this field.

Such forecasting was made more accessible by the production, starting in the fourteenth century, of calendars and ephemerides that gave pre‐calculated planetary positions over long runs of years, for stated regions. The arrival of print technology in the fifteenth century made it possible for the calculations of astronomers like Regiomontanus (1436–1476) to reach large numbers of users. Regiomontanus himself was an expert weather forecaster, and included his own rules in his Almanac, as well as an outline of ‘Weather forecasting according to Al‐Kindi’. By Regiomontanus’ time, it was an established requirement that the holders of university chairs in astronomy/astrology should produce annual prognostications, including weather forecasts, for the great and the good in their cities. Many of these were rushed into print and served as models for the popular almanacs, which were produced in impressively high numbers from the sixteenth century onwards. Astronomers such as Brahe and Kepler continued this medieval method of weather forecasting. Brahe argued for making both weather records and predictions, with the aim of increasing the accuracy of the forecasts by using more evidence (Brahe, 1901); and weather observations and prognostications made by Kepler from 1593–1624 survive. With such support, the demand for almanacs is not surprising. The more expensive ones provided daily weather forecasts for the coming year, in phraseology still echoed by modern forecasters. Winds were ‘variable’ or ‘fierce’, rain was ‘drizzling’, ‘driving’ or ‘showerie’, and good weather was ‘fair’ (Figure 8).

Indeed, one effect of the popularity of weather prognostications in the almanacs was the creation of a vocabulary of weather types. Key terms in English are already visible in the 1590 almanac shown above. By 1700, the term ‘overcast’ was in use, while cold and frost were still described as ‘sharp’ and the descriptor ‘unsettled’ had appeared, as had the promise that showers would ‘clear quickly’. Writing at the end of an unsettled August, it is striking to see that August 1709 was predicted to be rather similar. The almanac Merlinus Liberatus warned that late August would be a season of storms, while September would see ‘brisk winds’ and ‘unsettled’ conditions. The author discussed details of the wet summers of 1648, 1672, 1673, 1692 and 1708, and suggested that ‘those that have journals of the weather by them may make further observations’. Some of Dove's predictions for the same year would not sound entirely out of place in a modern forecast, since part of April was to be ‘cloudy, with rain in several places’, August has ‘showers, but soon clearing’ and September was to bring ‘wind and driving rain’.

It is this combination of an established language for forecasting and an emphasis on the importance of making records of actual weather that constitutes the most lasting legacy of medieval meteorology. The evidence presented here has shown that, by 1800, the idea that accurate recording of weather would increase the accuracy of forecasting was already 500 years old. A learned discourse for describing the weather in English came rather later, but still underlies the language of contemporary forecasters.

即使在二十一世纪，天气预报也可能具有挑战性，而公众对准确性的期望很高。但是，至少对于英国公众而言，抱怨恶劣的天气或天气预报的准确性确实提供了一个熟悉的话题。现在，天气预报已成为日常新闻周期的一部分。众所周知，它们与现代气象一起始于19世纪，并且每日天气预报首次出现在《泰晤士报》上（伦敦）于1861年8月成立。这个词本身是这种新型天气预报的创始人之一罗伯特·菲茨罗伊（Robert FitzRoy）创立的，他坚信天气预报应该作为公共服务发布，即使这对他造成了嘲笑。 ， 亲自。自1854年被任命为贸易委员会气象局局长以来，菲茨罗伊建立了15个沿海观测站，并且还能够使用电报的新技术使天气观测的接收和整理速度大大提高（Eden ，  2009年）。正是在1860年10月，他从爱尔兰西南海岸的瓦伦蒂亚天文台收到了第一份这样的电报，从1861年直到1865年他去世，他不仅有责任发布报告，而且要警告即将来临的天气。菲茨罗伊（FitzRoy）创造新名词的意图是要明确表明，他的“预测”使用的是基于可靠数据收集的科学程序，与随后每年以廉价年鉴出版的“预测”无关。

这些历书由占星家发行，并在1800年被越来越多的人嘲笑。由于它们不是基于对亚里士多德著作的学术评论，因此也被排除在现代现代气象学史之外（Martin，  2011年）。但是，一些作者对其悠久的方法提出了“现代”论点。一个非常受欢迎的头衔是Vox Stellarum，是由文具公司于1700年发行的，在整个19世纪的大部分时间里，弗朗西斯·摩尔（Francis Moore）一直被认为是杰出的（使他对“老摩尔”的称呼非常恰当）。到1804年，作者已经在与更新的天气预报方法竞争，并自豪地引用了上一年的月度降雨测量值，“取自伦敦皇家学会的房子”。在接下来的几十年中，每月进行降雨量测量的地方数量大大增加，并且也关注了大气压力。编制者将这些数据的分析与他的占星术预测相结合，以产生关于降雨时间和降雨量的勇敢预测。他敦促如果在整个王国范围内保存“天气新闻”并每年出版一次，“随着时间的流逝，这将使气象学更加完善”。到1848年，还敦促他的读者使用晴雨表，以增加气象知识并证明传统预测的功效。后见之明清楚地表明，当之无愧是费兹罗伊的方法。但是尝试将科学方法和占星术信念相结合的尝试却有着悠久且具有影响力的历史（图1）。

中世纪的天文学家/占星家已经使用对实际天气的详细观测以及复杂的天文和数学计算得出了预报。我的研究（Lawrence-Mathers，  2019）表明，从九世纪到十八世纪，这些方法都得到了认真的对待。在16世纪和17世纪，天文学家Tycho Brahe和Johannes Kepler仍然做出了这种预测，并仍然建议收集数据以提高准确性。涉及的科学理论始于古典天文学，它支持天体（尤其是行星）对地球及其居民施加强大力量的观点。人们认为每个星球都有一套特定的质量和能力，这些能力和能力影响了地球上的相关现象。伊斯兰世界中自然哲学家利用古典希腊，希腊，波斯和印度当局的著作，详细阐述了这是如何工作的。地球固定在其中心的亚里士多德宇宙模型，

伊斯兰科学家假设，地球被由四个经典元素（地球，水，空气和火）组成的球包围，而四个元素又被行星所携带的球包围。行星和恒星都发出到达地球表面的射线，并在途中彼此相互作用，并与元素球相互作用。

也许最有影响力的是伟大的哲学家，科学家，肯迪（参数Ç。800-870 CE）（伯内特，  2004年）。他接受了这样的理论，即天体的运动会产生热量，进而在地球周围的大气层中产生运动并发生变化。此外，他认为，行星射线的影响详细确定了气象现象如何在地球上波动。自上古以来，每个行星的品质和元素亲和力都得到了认可，例如，土星与地球元素特别相关，并且干燥而寒冷。因此，其射线将具有这些属性。该系统中最强大的是太阳和月亮，所有受过教育的人都知道其对诸如季节，气候，日光，潮汐和（据称）体液和植物生长等现象的影响。

亚历山德里亚的克劳迪乌斯·托勒密（Claudius Ptolemy）已经为该理论提供了数学和几何精度，他是第二世纪的伟大地理学家，宇宙学家和天文学家。托勒密的主要贡献是产生了复杂的模型，从而可以相当准确地预测任何选定日期的行星位置（Almagest，托勒密，  1998年）。edn）。正如托勒密所说，这反过来意味着有可能计算出它们的作用如何相互作用，以及对地球的大气和天气会产生什么样的结果。托勒密概述了如何通过解释所选日期所有重要天体相对于彼此以及相对于地球表面指定点的计算位置来做出详细的天气预报（Tetrabiblos，托勒密，  1940年）edn）。记录位置的标准方法是按黄道上的度数和经度数表示，用十二生肖圆的十二等分表示。这一点很重要，因为这些划分（称为房屋或标志）的特征很大程度上取决于它们附近或附近的恒星，并且会影响附近的行星（图4）。

为了量化行星之间的相互作用，还必须注意它们所占据的房屋之间的角度关系，以及它们是朝着彼此移动还是彼此远离。当考虑涉及强大且快速移动的月球的互动时，后者尤其重要。托勒密对该理论的总结是：“很明显，当行星彼此之间有着显着的联系时，它们会在我们的大气质量中产生很多变化，每个行星的内在力量都保留下来，但是其力量却被力量所改变。构成它的身体的一部分”（Tetrabiblos，第45页）。因此，当涉及到产生实际预测时，一个看似简单的模型可以生成相对大量的数据。

从九世纪开始，阿拉伯帝国的哲学家将新数据汇编到更新的行星表中，并完善了托勒密的天气预报方法。从11世纪后期开始，欧洲学者逐渐吸收了他们的作品，并在13世纪将其纳入大学的天文学教学中。进行更广泛而成功的预测的主要障碍是所涉及计算的复杂性，但是数学的进步和印度－阿拉伯数字的采用帮助克服了这一问题。同样重要的是，新的“星际科学”中广受赞誉的专家的崛起，他们成功地进行了成功的预测和预报，并在政治中心和大学中都发挥了重要作用。拉丁文的传播使Al-Kindi成为这样的专家，以及他对大气和天气如何运作以及高温和低温，干旱和雨水以及风的成因的概述，一直持续到16世纪。在挑战亚里士多德对其中某些现象，特别是对风的观点时，他是不寻常的。虽然“哲学家”将风与发生在地球表面上方和下方的“呼气”相关联，但Al-Kindi更喜欢将热量作为基本驱动力。他指出，太阳和月球的共同影响决定了特定区域空气中的热量水平，而热空气将迅速膨胀到冷空气收缩的区域，从而确定了风的强度和方向（劳伦斯·马瑟斯 直到16世纪，风仍然具有影响力。在挑战亚里斯多德对其中一些现象，特别是对风的观点时，他是不寻常的。虽然“哲学家”将风与发生在地球表面上方和下方的“呼气”相关联，但Al-Kindi更喜欢将热量作为基本驱动力。他指出，太阳和月球的共同影响决定了特定区域空气中的热量水平，而热空气将迅速膨胀到冷空气收缩的区域，从而确定了风的强度和方向（劳伦斯·马瑟斯 直到16世纪，风仍然具有影响力。在挑战亚里士多德对其中某些现象，特别是对风的观点时，他是不寻常的。虽然“哲学家”将风与发生在地球表面上方和下方的“呼气”相关联，但Al-Kindi更喜欢将热量作为基本驱动力。他指出，太阳和月球的共同影响决定了特定区域空气中的热量水平，而热空气将迅速膨胀到冷空气收缩的区域，从而确定了风的强度和方向（劳伦斯·马瑟斯 虽然“哲学家”将风与发生在地球表面上方和下方的“呼气”相关联，但Al-Kindi更喜欢将热量作为基本驱动力。他指出，太阳和月球的共同影响决定了特定区域空气中的热量水平，而热空气将迅速膨胀到冷空气收缩的区域，从而确定了风的强度和方向（劳伦斯·马瑟斯 虽然“哲学家”将风与发生在地球表面上方和下方的“呼气”相关联，但Al-Kindi更喜欢将热量作为基本驱动力。他指出，太阳和月球的共同影响决定了特定区域空气中的热量水平，而热空气将迅速膨胀到冷空气收缩的区域，从而确定了风的强度和方向（劳伦斯·马瑟斯2019年，第82–84页）（图5）。

拉丁美洲最受欢迎的天气预报论文之一是13世纪的科学家，林肯主教罗伯特·格罗斯泰斯特（Robert Grosseteste）。这提供了一种简化的预测方法，并敦促干旱或洪水预警可以挽救许多生命。后来，一些从业者因其预测而声名great起。牛津大学的天文学家/占星家约翰·埃森登（John of Eschenden）曾因预言1348/1349的大灾而备受赞誉，尽管他的预言实际上相当模糊。他持续进行的关于寒冷，潮湿和大风天气的预后，导致洪水和饥荒持续到1370年代，也被认为是正确的。应当指出，行星对物质现象（包括大气及其运动）的影响对中世纪教会没有任何神学问题。

通过对天气进行详细观察并将其与天气预报相关联的不断发展的实践，进一步表明了中世纪后期进行天气预报的严肃工作。已知最早的例子来自英格兰和德国。也许最早的天气记录是在1269/1270年日历的空白处输入的，该记录是在罗杰·培根（Roger Bacon）的藏品中发现的，该藏品于13世纪后期在牛津放在一起。出版了完整的翻译本（天气杂志，第29（6）页，Long，1974年）），然后并置被认为令人费解。根据培根的论点，即天文学家像所有其他科学家一样，应将其模型“经过经验检验”以提高其效用，比较行星位置与实际天气的概念似乎与培根建立科学的动力相一致。 （包括现在被归为占星术的事物）对社会的基本价值（图7）。

正如14世纪在牛津，林肯，维尔茨堡和（可能）巴塞尔的气象观测资料与行星数据一起汇编和研究所表明的那样，类似的工作也得到了认真对待。威廉·德·梅尔大师发布的“天气预报规则”伴随着1337–1344年的记录，该规则与牛津的默顿学院和威廉·里德（1369–1385年的奇切斯特主教）有联系[西蒙斯，  1891年]。在巴塞尔手稿中，发现了1399年至1406年的天气记录，并记录了可能与之相关的天文气象因素。例如，1400年4月7日多云，晴天间隔短，西风强烈。值得注意的是，月球在接近已知会造成空气干扰的水星时，从仁慈的行星木星移出了空中标志。然而，这种经验研究的效果令人惊讶，是增加了对基于天文学的天气预报的信心。可以说，获得可靠预报的途径是通过收集记录并与气象模型一起进行分析，这一想法是中世纪科学在该领域的重要遗产。

从十四世纪开始，通过日历和星历表的生产，可以更方便地进行此类预测，这些日历和表历在指定的区域内可以长期提供经过预先计算的行星位置。十五世纪印刷技术的到来使得诸如Regiomontanus（1436–1476）这样的天文学家的计算有可能吸引大量用户。Regiomontanus本人是专家天气预报员，并在自己的年历中包括了自己的规则，以及“根据Al-Kindi进行天气预报”的概述。在雷焦蒙塔努斯（Regiomontanus）时代，已经确立的要求是，天文学/天文学的大学教席持有人必须为城市中的大事和好事提供年度预报，包括天气预报。这些书中有许多被匆匆印刷成册，并作为流行历书的模型，这些历书从16世纪开始就大量生产。布拉赫（Brahe）和开普勒（Kepler）等天文学家继续采用这种中世纪的天气预报方法。布拉赫（Brahe）主张同时进行天气预报和天气预报，目的是通过使用更多证据来提高天气预报的准确性（布拉赫（Brahe，  1901））; 开普勒在1593年至1624年之间所做的天气观测和预后都可以幸免。在这样的支持下，对历书的需求不足为奇。较昂贵的天气预报提供了来年的每日天气预报，但在措辞上仍得到现代天气预报员的回响。风是“多变的”或“剧烈的”，雨是“滴水的”，“开车的”或“花哨的”，好天气是“平常的”（图8）。

确实，天气预测在历书中流行的一个影响是创造了天气类型的词汇表。上面显示的1590年历中已经可以看到英语中的关键术语。到1700年，“阴雨”一词已被使用，而寒冷和霜冻仍被描述为“锋利”，并且出现了“未解决”的描述，还有关于淋浴将“迅速清除”的保证。令人震惊的是，预言1709年8月将是非常相似的，这是在未解决的8月底写的。年历Merlinus Liberatus警告说，八月下旬将是暴风雨的季节，而九月将出现“狂风”和“动荡”的状况。作者讨论了1648年，1672年，1673年，1692年和1708年夏季潮湿的细节，并建议“那些有天气日志的人可以做进一步的观察”。Dove对同一年的某些预测在现代预测中听起来并不完全不合时宜，因为4月的部分时间是“阴天，有几处降雨”，8月有“阵雨，但很快就晴了”，而9月则是带来“风吹雨打”。

正是这种既定的预报语言和对记录实际天气的重要性的结合，构成了中世纪气象学中最持久的遗产。这里提供的证据表明，到1800年，准确记录天气会提高预报准确性的想法已经有500年的历史了。一种用英语描述天气的学问很晚，但仍然是当代预报员语言的基础。