Weather report

“ Rain storms are preceded from twelve to forty-eight hours by barometer falling steadily, increasing humidity, high temperature, with wind east or south, cirro-stratus clouds in southern or western horizon, and eastern horizon obscured by haze.
Red sky at sunrise indicates strong winds; if humidity is much below the mean, the color is usually a brilliant scarlet; if humidity is high, the color is more crimson, with a purple tinge and rain follows. When wind backs from northwest to southwest, clear weather follows. ”

“ The popular idea seems to be that certain scientific men who have given the subject considerable study, cast a knowing eye on the evening sky, and pass on written prognostications for use in the morning papers.
HOUSES WRECKED BY A TORNADO.
As a matter of fact the method by which we obtain our weather reports and forecasts is very different, and savours even more strongly of romance than the clairvoyant system usually identified with the seers of the weather office. ”

“ If when it falls the temperature rises, and the air becomes more charged with moisture; then wind, rain (or snow) may be expected from the S.E., S., or S.W.
Exceptions to these rules occur when a Northerly wind with wet (rain, snow, or thunderstorm) , is impending, previous to which the barometer often rises (but only on account of the direction of the coming wind) , and thus deceives those who from the rising are led to look for fair weather. ”

“ Rapidly falling barometer, rising temperature, and light southerly winds indicate rain or snow, according to season of year.
Falling barometer, rising temperature, with wind from northeast or east, indicate snow.
Fine cirrus and cirro-stratus, floating low, presage wind.
Haze in night or early morning, or cumulus clouds, sharp and well defined, moving from west or southwest, indicate fair weather.
When snow is falling, and the wind backs from east to north, with decreasing velocity, clear weather may be expected. ”

“ In winter a storm usually follows a falling barometer, with south wind. If barometer falls one-tenth of an inch between 7 a. m. and 12 m., bad weather follows within thirty hours. In winter, high temperatures are generally followed by bad weather, especially if accompanied by winds varying from northwest to northeast.
Increase of humidity between 12 m. and 3 p. m. is usually followed by rain before night on same day.
Backing of wind to southward, with falling barometer, nearly always followed by bad weather.
All wavy forms of cirro-stratus are sure signs of an approaching storm. ”

“ There is not a profession, or trade, or handicraft in society which is not at every turn more or less influenced by the weather, and compelled to act upon some kind of weather-forecasts. No sooner had the Weather Bureau commenced its daily publication of "Probabilities" or "Indications," in 1870, than "whole troops of practical applications" of the data sprang into existence. It will be so with the international bulletin and charts of simultaneous meteorology. ”

“ A Steady Barometer.—With dry air and seasonable temperature indicates a continuance of very fine weather.
A Falling Barometer.—A rapid fall indicates stormy weather. A rapid fall with westerly wind indicates stormy weather from the northward. A fall with a northerly wind indicates storm, with rain and hail in summer, and snow in winter. A fall with increased moisture in the air and heat increasing indicates wind and rain from the southward. A fall with dry air and cold increasing in winter indicates snow. A fall after very calm and warm weather indicates rain with squally weather. ”

“ These observations, which consist of the reading of barometer and thermometer, the determination of the velocity and direction of the wind, the determination of the humidity and of the amount of rain or snow, are telegraphed to the chief weather official at Washington. From the reports of wind storms, excessive rainfall, hot waves, clearing weather, etc., and their rate of travel, the chief officials predict where the storms, etc., will be at a definite future time. ”

“ It is from similar maps that forecasts of storms are still framed, and suitable warnings issued; and a mass of information is being collected by telegraph from sixty stations in the British Islands, &c., of the state of the weather at eight o’clock every morning, and analysed and arranged at the Meteorological Office in London for the evening’s forecasts over the different districts of the country. A juster knowledge is being now acquired of those great atmospheric movements, and other changes, which form the groundwork of weather-forecasting. ”

“ Another weather type, often noted during our winter in the central and eastern United States, and strongly contrasted with both of the preceding conditions, is that which brings us a warm, damp, southerly wind, frequently accompanied by heavy rains. As these damp winds blow over snow-covered surfaces they become foggy and the ground is said to “smoke”; the heavy rain rapidly melts the snow; slush and mud make bad walking; rivers and brooks rise rapidly, perhaps overflowing their banks; low-lying places become filled with standing water. ”

“ Since 1871 a still more careful analysis of the United States daily weather maps has shown that it is necessary to consider the fact that the winds on the west side are colder and drier than those on the east side of the storm center. ”

“ Showers undoubtedly occurred in conjunction with Post’s experiments, but conditions favoring their occurrence were plainly indicated on the current daily weather maps, and they had been duly forecast by the Weather Bureau.
The professional rain-maker does not generally resort to the expensive process of bombarding the clouds. ”

“ Wind-storms are preceded by a low barometer, with much briefer warning than in the case of rain and snow storms, often occurring within two or three hours after the first instrumental premonition. Temperature rises and humidity increases; cirrus clouds move from west to northwest. ”

“ The ranchmen in the West, with thousands of cattle under their charge; the trainmen in charge of cattle trains; the engineers of large buildings, such as hotels, stores, and office buildings, who must have their fires hotter in cold weather,—these and many more watch, and are governed by, the cold-wave forecasts of our Weather Bureau.
Mean Annual and Mean Monthly Isothermal Charts.—We have thus far considered isothermal charts for the United States only, based on the temperature observations made at a single moment of time. ”

“ A rise in the dew-point from morning to noon will be followed by rain: a fall by fine weather.
The evening dew-point generally determines the mean temperature of the night. If, therefore, this be ascertained, the approach of low temperature or of a frost at night may be seen and provided against.
A high evening dew-point indicates, if the dry bulb does not fall much, that the next day will probably be warm, but a high evening dew-point with a chilly air and a S.W. wind is rather a presage of rain. ”

“ Sometimes severe weather from the S., which will not last long, may cause no great fall, because a northerly wind is impending; and at times the barometer may fall with northerly winds and fine weather apparently against the common rules, because continued southerly wind is impending. ”

“ Almost every daily paper publishes a résumé of the weather map; some reproduce the map itself. All told, the daily forecast is so widely published that it is within almost instant reach of everyone within the main body of the country. ”

“ The weather map of the United States is based on simultaneous observations made at about 150 stations in different parts of this country, besides several coöperating stations in Canada, Central America, Mexico, and the West Indies. At each of our stations, whose48 location may be seen on any weather map, the Weather Bureau employs one or more observers, who, twice a day, at 8 A.M. and 8 P.M., “Eastern Standard Time,” make regular observations of the ordinary weather elements, i.e., temperature, pressure, humidity, wind direction and velocity, precipitation, cloudiness, etc. ”

“ The study of the atmosphere and its phenomena. Efforts are being made by every civilized nation to apply to the benefit of mankind the knowledge we possess of meteorology, especially to foretell the winds and weather from day to day and the general character of the seasons from season to season. About fifty official governmental weather bureaus receive reports from their stations by telegraph daily, compile weather maps, issue forecasts, and publish weekly, monthly, or annual climatological summaries, together with frequent special meteorological memoirs. ”

“ When one thinks of the accumulation of meteorological minutiæ which is resulting from the preservation of the reports from so many places as to the wind, rain, sunshine, and all the rest of it, one may be tempted to ask whether it is worth the trouble it involves? If the observations are of use to those who want to know the probable state of the weather during the next twenty-four hours, where can be the utility of tabulating them year after year with as much care as is exercised in the registering of births, marriages, and deaths? ”

“ When you see a halo about the top of a mountain, you know that bad weather is expected. The same is true when a halo appears about the moon. This indicates rain, or if the lower clouds break up and the upper clouds, or a second light covering of clouds, are seen above the lower ones, it speaks for continued bad weather. In some localities if rainy weather is continuing for some time, and a certain change in wind sets in, it will indicate that good weather is coming. ”

“ If this disposition to condensation becomes extensive, cirri form and run into cirro-stratus, or they extend, coalesce, and form stratus; the surface-wind will be attracted under them, the thermometer fall in summer or rise in winter, and a storm begin. Intense action and sudden cold may exist in and under this counter-trade over the southern portion of the country, while all is calm, warm, and balmy at the north. Heavy snow storms sometimes pass at the south when there are none at the north, and a corresponding state of the weather follows. ”

“ It must occur to everyone to adopt the intermediate view that, on the one hand, the local vertical circulation, with its clouds, rain, hail and snow, and evolution of latent heat, and, on the other hand the waves and whirls in the general circulation, mutually contribute toward our storms and fair weather. It only remains to allot to each its proper importance in any special case.
Undoubtedly aerial billows, and the clouds that must frequently accompany them, exist everywhere in the earth’s atmosphere. ”

“ By preserving the weather map each day and noting the movements of the Highs and the Lows, any intelligent person can make a fairly accurate forecast for himself, always remembering that the Lows, as they drift towards him, will bring warmer weather and sometimes rain or snow, and that as they pass his place of observation the Highs following in the tracks of the Lows will bring cooler and fair weather, except during periods of extreme summer heat, when the Lows bring showers that cool the parched earth ”

“ The cooperative observer can do much to aid in establishing definite facts on which predictions may be made. Among them and of first importance is establishment of the direction of rain-winds. These, as has been shown, are easterly winds, but conditions of topography may change the real direction to one that is apparent. The apparent direction should be established for each month in the year. In every community there are weather-wise people who possess valuable information that they have not recorded. ”

“ The Weather Bureau does not possess on its books the record of any two days when the weather was duplicated over the United States."
"You mean that every day's weather map is different?"
"As different as every human face," the Forecaster replied, "and to those of us who have done much forecasting, it is as easy to see from the map when the weather is going to be peaceful or stormy as it is to tell whether a man is smiling or scowling. But let us look at these three charts closely, and you will see just why Fred was right. ”

“ Barometer moves rapidly for a storm of short duration, temperature rises, wind from east-southeast, south and southwest, from eight to twenty-four hours previously, with upper clouds moving from the west, wind stronger and of greater duration, with rising rather than falling barometer. Rapid movement of cirro-stratus clouds indicates wind, but is seldom observed. ”

“ They are characterized in their eastern quadrants by cloudy weather, southerly and easterly winds, precipitation, temperature oppressive in summer and abnormally high in winter, falling barometer, increasing humidity and followed by clear weather, rising barometer, decreasing humidity and falling temperature in the western quadrants.
Buys Ballot’s law of winds is, that in the Northern Hemisphere if one stands with his back to the wind, the low barometric pressure will be invariably to the left hand; in the Southern Hemisphere the lowest pressure is always to the right. ”

“ Man is so profoundly affected by weather changes from day to day that all civilized countries have established weather services. Observers taking regular weather records are stationed at thousands of different places in all parts of the world, and the observations which they makexii are used by meteorologists in preparing daily weather maps and forecasts, and in studying the conditions of temperature, winds, and rainfall. In the United States alone there are about 3000 of these observers. ”

“ Misty clouds, forming or hanging on heights, show wind and rain coming, if they remain, increase, or descend; if they rise or disperse, the weather will improve or become fine.
RAIN. The atmosphere at a given temperature is capable of retaining only a given quantity of aqueous vapour, invisibly diffused through it, at which temperature it is said to be saturated. Should the temperature from any cause be lowered, the aqueous vapour at once becomes visible in the form of either cloud, dew, rain, snow, or hail. ”