Weather Map
January 9, 1886
THE WEATHER IN CYCLONES AND ANTICYCLONES
SENDING UP A METEOROLOGICAL BALLOON ON LAKE CONSTANCE
Between Switzerland and Germany.
Barometric pressure is not an element of weather, in the ordinary sense of the term, since the fluctuations of pressure that occur in the human environment are entirely inappreciable to the senses. We have seen, however, that pressure is intimately related to wind, which is a weather element of much importance. In noting that systems of high and low pressure are constantly traveling across the country, and that they are accompanied by winds having fairly definite characteristics in relation to each, we have taken an important step toward bringing order out of the (to the uninitiated) chaotic sequence of weather. Obviously, a system of telegraphic weather reports makes it possible to keep close watch of these wind systems, and, from their locations on today's weather map, to form some idea where they will be tomorrow. Thus the weather forecaster is enabled to give notice of the imminence of those violent winds that destroy life and property at sea, and, to a less extent, on land. There is an element of uncertainty in such predictions—since storms, unlike railway trains, are not confined to fixed routes and regular schedules—but the practised forecaster acquires an instinct that helps him to forestall their vagaries.
MARVIN RAIN AND SNOW GAGE
With trumpet-shaped wind-shield at top. In the middle is seen the cylindrical collector. This is removed and weighed with its contents to ascertain the amount of rain or snow that has fallen
Now what is true of wind is also true to a certain extent of the other elements of weather,—they bear typical relations to the distribution of atmospheric pressure. Cyclones are usually preceded by rising temperature and accompanied by cloudiness and rain or snow; anticyclones are usually preceded by falling temperature and attended by fair weather.