Forecast

“ 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. ”

“ But if a change is not forecast, or if the words ”not much change,” ”slight change,” ”continued warm,” (or cool) , or ”stationary temperature” are used, a definite number of degrees (6 in summer and 10 in winter) is required to vitiate the forecast. Modifying words, “slightly,” “much,” “probably,” etc., do not relieve the forecaster of the failure of his verification.
Time of Occurrence.— The forecasts most generally sent out for publication are based on the 8:00 a.m. ”

“ The making of a single forecast in any one of the meteorological offices of Europe, America, Australia, or the Far East requires the organized cooperation of some hundreds of persons; about a hundred observers who note the necessary observations simultaneously at as many separate places and hand in their reports to the telegraphists who transmit them to one center, where the meteorological expert charts them on a map and draws therefrom the conclusions on which the forecasts are based. ”

“ 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 ”

“ It is the expectation of the meteorologist that some day he will be able to accurately forecast the weather for weeks and months in advance. What a wonderful conservation of human energy would result if it were possible to tell the farmer when the great corn and wheat belts would have abundant rain during the next growing season, or when droughts would parch and wither the vegetation ”

“ There are many other obstacles in the way which combine to render weather forecasting extremely difficult. Some of these difficulties you will learn to overcome more or less successfully by the experience you will gain from a careful and persevering study of the daily weather maps; others, the best forecast officials of our Weather Bureau have not yet entirely overcome. ”

“ In some cases the larger portion of the funds and forces of a weather service is spent upon observations and climatological work, but in most cases the daily forecast work takes precedence, since that promises immediate results in saving life and property. ”

“ I do think that, of all the silly, irritating tomfoolishness by which we are plagued, this “weather-forecast” fraud is about the most aggravating. It “forecasts” precisely what happened yesterday or a the day before, and precisely the opposite of what is going to happen to-day. ”

“ The accuracy of the forecast decreases with the length of the forecast period. A 12-hour forecast is likely to be more reliable than a 24-hour forecast. Long term forecasts for 2 weeks or a month in advance are limited to general statements. For example, a prediction may be made about which areas will have temperatures above or below normal, and how precipitation will compare with normal, but no attempt is made to state that rainfall will occur at a certain time and place. ”

“ There are probably many people among us, well above the illiterate level, who have no clear idea as to what constitutes a scientific weather forecast. The distinguishing feature of such a prediction, apart from the fact that it is made by a trained meteorologist, is that it is, in all cases, based upon a weather map.
The forecasting machine is a big one, with its human gear spread over a wide territory. Eventually it will be spread over the entire globe, and then we shall have better forecasts. ”

“ With photographs illustrating the queer side of the matter.
IN most of the morning papers we are accustomed to the luxury of a detailed weather report and forecast. The majority glance at it with a sceptical smile. They are of opinion that in order to be on the safe side they must invert its message. If fine weather and sunshine are predicted, they sagely nod and take down the homely gamp. The prediction of a hurricane or stormy showers is the signal for leaving umbrellas and overcoats at home. ”

“ We have generally found country folk more reliable about the immediate future of the weather than the falling or rising of the barometer, for local conditions are often an important factor in the case and modify the barometer’s forecast. ”

“ Could the rural populations and those whose occupation calls them much out of doors be assisted in interpreting these and similar phenomena, however untutored they might be in meteorologic terms and theories, they would soon learn to forecast many of the great weather-changes for themselves. ”

“ In framing official predictions of the weather the daily synoptic and isobaric chart is the chief evidence relied upon.
To forecast with any degree of accuracy requires considerable experience, a knowledge of the distribution of the normal local climatic elements, and a due appreciation of the significance of the varying features of atmospheric systems and the degree to which they are affected by latitude, longitude, the seasons of the year, and, at times, even by the prevailing conditions of the land surface over which the atmospheric systems are passing. ”

“ From season to season in these high altitudes local conditions vary to an extent which makes it impossible to forecast the difficulties which may obtrude themselves during any one month or even for any one summer. ”

“ In spring and autumn a sudden fall indicates rain; in the summer, if very hot, it foretells a storm. In the winter, after a period of steady frost, a fall prognosticates a change of wind with rain and hail; whilst a rise announces the approach of snow.
6. Rapid oscillations of the mercury either way are not to be interpreted as indicating either wet or dry weather of any duration; continuance of either fair or foul weather is forecast only by a prolonged and steady rise or fall beforehand. ”

“ Charts are then prepared for distribution, showing the direction and force or the wind, the barometrical pressure, the temperature, and the atmospheric conditions generally. The comprehensive idea which the Office thus acquires of what Nature is doing over a considerable portion of the earth's surface, enables it to accomplish two useful pieces of work—to forecast the weather for the next twenty-four hours, and, if necessary, to warn particular localities to look out for squalls. ”

“ This extension of forecasting doubtless will be accomplished as the result of further study of solar impulses which disturb the orderly processes of the earth’s atmosphere and initiate storms, combined with a comparative study of meteorological data. We may be laying the foundation of a great edifice which shall adorn the civilization of future centuries. ”

“ In countries where the most important interests are manufacturing and ocean transportation, the 'weather' is the first consideration; in lands where the agricultural interests are predominant, although the weather is important, it is more essential to have an idea of the climatic or seasonal changes. Thus if the sunspot period could be shown to have a large influence on the climate of any region, we should be able to forecast to a corresponding extent the general characteristics of future seasons, and lay plans accordingly. ”

“ THE IMPORTANCE OF METEOROLOGY: ITS RELATIONS TO MAN.
We live in the laboratory of the earth’s atmosphere. The changes from hot to cold, wet to dry, clear to cloudy, or the reverse, profoundly affect us. We make and unmake our daily plans; we study or we enjoy vacations; we vary our amusements and our clothing according to these changes. The weather forecasts for the day in the newspaper are read even before the telegraphic despatches of important events. Sailors about to put to sea govern themselves according to the storm warnings of our Weather Bureau. ”

“ The prediction or foretelling of the weather which may be expected to prevail at any station or in any district is weather forecasting.
Weather forecasts are usually made on our daily weather maps for 24 hours in advance. It is by no means an easy thing to make accurate weather forecasts. Careful study and much practice are required of the forecasters of the Weather Bureau before they are permitted to make the official forecasts which are printed on the daily maps and in the newspapers. ”

“ The Barometer as a Weather-glass.—Generally speaking when the mercurial column in the barometer falls, ‘rain’ is indicated, and ‘fair weather’ when it rises. When it continues steady, a continuance of the weather at the time is regarded as the forecast; when low, the weather is generally broken or bad; and when high, it is fair and settled. A storm is usually preceded by a sudden fall in the mercurial column, the violence of the storm being in proportion to the suddenness of the fall. ”

“ The success that you attain will depend upon the accuracy of the instruments and the care you use in reading them. You will be able to rig up a Weather Bureau of your own, and the use of these instruments will interest anyone in a study of the weather.
THE WEATHER VANE To make a forecast, it is essential from what we have already written, to know the direction of the wind, and to determine the direction we must have a weather vane. It is real important that the vane should be sensitive to the slightest movement of the wind and give actual wind directions. ”

“ Forecasting Weather The prediction of weather at some future time is based upon an understanding of weather processes and observations of present conditions. Thus, when there is a certain sequence of cloud types, rain usually can be expected to follow. If the sky is cloudless, more heat will be received from the Sun by day, and more heat will be radiated outward from the warm Earth by night than if the sky is overcast. If the wind is from a direction that transports warm, moist air over a colder surface, fog can be expected. ”

“ It is evident, therefore, that a complete knowledge of the weather conditions in any part of the world, which it is understood carries with it the ability to make correct forecasts, can never be obtained unless the weather conditions in every other part are known. ”

“ 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. ”

“ The most popular and profitable use to which meteorologic observations can possibly be put would be, if it is practicable, to forecasting in part the character of coming seasons—whether the next winter will be mild or severe, or the approaching summer wet or dry. ”

“ With the principles of this science all the more reliable rules of weather-forecasting are most intimately connected. We no longer think of judging of coming weather merely by the aspect of the sky and an examination of an individual barometer. We invariably refer—I do not say to the weather-reports of a few hours previous, for we often have neither these nor any weather-reports at all at hand—but we invariably refer to rules already deduced from the long study of weather-maps. The man who ignores these rules had better, in my opinion, leave all attempts at weather-forecasting alone. ”

“ These governmental bureaus usually pursue both Climatology and theoretical meteorology in addition to their daily practical work of telegraphy, forecasting, and publication of charts. Although, of course, in most cases, the so-called practical work absorbs the greater part of the labour and the funds, yet everywhere it is recognized that research and the development of a correct theory of the motions of the atmosphere are essential to any important progress in the art of forecasting. ”

“ The universal interest in the weather, which makes it the most common topic of conversation, is due to its effect upon health, business, and pleasure. Official forecasts of the weather are given a place of prominence on the front page of most papers, and are read with interest by most readers. The business man, the farmer, the shopper, the pleasure-seeker, all are concerned with the state of the weather and the predictions regarding it. ”

“ 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. ”

“ That we live in an age of great intellectual acumen, and that he is indeed a wise prophet who can even dimly outline the possibilities of the next century, is fitly shown by the development of meteorological science during the recollection of the present generation; although one must admit that in the making of weather forecasts, valuable as they are, we have not advanced beyond the partly empirical stage. ”

“ 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. ”