LOCAL WEATHER SIGNS.

The following summaries of local weather signs are based on special reports of observers to the Chief of the United States Weather Bureau:

ABILENE, TEX.

During late spring, summer, and early autumn precipitation is usually preceded twelve to twenty-four hours by south to southeast winds and falling barometer, and the barometer generally falls to 29.80 or below before precipitation begins. During the colder months precipitation often begins when the barometer has fallen to 30 and is on the turn from falling to rising, and at the time the wind shifts to colder northwest.

Precipitation is preceded by relative humidity that increases to 75 or 80 per cent.

Cirrus and cirro-stratus clouds move from the west, but the relation of these clouds to rain has not been noted by the observer, who associates stratus and cumulo-nimbus clouds with rain.

The highest winds of winter come from the northwest with rising barometer, and of summer from the southeast with falling barometer. During periods of abnormally high temperature south to southeast winds prevail, except in summer, when they come from the southwest. During periods of abnormally low temperature the winds are from westerly in spring and winter, and from northwesterly in summer and autumn.

Frost is most likely to damage crops in April and November.

The conditions most favorable for frost are: Rising, or high and stationary, barometer, temperature falling to 40° or below, increasing relative humidity, clear weather or cirrus clouds, and light west to north winds.

ALBANY, N. Y.

Precipitation is usually preceded in all seasons by south and southeast winds, which set in twenty-four to forty-eight hours before precipitation begins, and barometric pressure which usually falls to or below 29.90 to 29.95 in spring and summer, and to 30 inches or below in autumn and winter.

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Except in the presence of fog, which indicates clearing weather, the relative humidity generally increases during twenty-four hours preceding precipitation.

Usually, but not necessarily, cirrus clouds moving from the west precede precipitation about twenty-four hours in all seasons. Altostratus clouds from the west or southwest usually precede rain from twelve to forty-eight hours. In spring and summer detached cumulus clouds, moving rapidly from the southwest under a veil of alto-stratus, sometimes appear about twelve hours before rain.

In spring, summer, and winter, high north to west winds usually occur with a rising barometer, and in autumn with a falling barometer and wind from the southeast. In all seasons wind is from the south during periods of abnormally high temperature. In spring and winter the cold winds are from the west and north, in summer from west, and in autumn from west to northwest.

Frosts in May and June are most likely to damage fruit, and frosts in September are most likely to damage other crops.

The conditions which precede frost are barometer above 30.12, temperature about 40°, humidity high. In winter there are two kinds of frost, one a shotted-formed frost, the other of a spongy character; the former is observed in advance of "dry" low barometer areas, the latter in advance of storms from the southwest.

ALPENA, MICH.

In spring and summer southeast winds and falling barometer precede precipitation for periods that vary from a few hours to several days, and the barometer usually falls to 29.90 or below before precipitation begins. During the colder months there is frequently light precipitation in the rear of areas of low barometer. In such cases, however, precipitation has occurred in front of the low areas.

Atmospheric moisture is unreliable as an indicator of precipitation, and while in a majority of cases the relative humidity has increased during twenty-four hours preceding precipitation there are many instances of precipitation that have been preceded by a decrease in relative humidity.

The only upper clouds that are at all reliable as indicators of precipitation are the cirro-stratus "veil." These clouds may occur in any season, but are seldom observed. In spring and autumn clouds become stratus several hours before precipitation begins. In summer small, heavy-looking cumulus clouds usually precede rain; in winter stratus and strato-cumulus prevail, and there are but few clear days.

High winds may come from any quarter in any season, but they are more frequent from the northwest with rising barometer. In all seasons abnormally warm winds are usually from the southwest, and cold winds from the west and northwest.

Frost is likely to damage fruit or crops from May 15 to October 1. The conditions favorable for frost are: Clear weather, light winds, decreasing humidity, rising and high barometer, and falling temperature.

AMARILLO, TEX.

South to southeast winds usually set in twenty-four to forty-eight hours before precipitation, with falling barometer, which reaches 29.85 to 29.90 or below in spring and summer and 30.05 or below in autumn and winter. Precipitation begins, however, after the barometer begins to rise, and in the colder months after the wind has shifted to northerly, the most marked exception to this rule being noted in June, when rain commonly begins with falling barometer.

In all seasons there is a rapid decrease in relative humidity until thirty-six to forty-eight hours before precipitation begins in spring and winter, and twenty-four to thirty-six hours before precipitation begins in summer and autumn, and after the minimum per cent has been reached the humidity rapidly increases until rain begins. A sudden and decided increase in humidity indicates precipitation, unless it follows a heavy rain.

In spring cirro-stratus followed by alto-stratus clouds indicate rain. In summer rain follows cirro-stratus, passing through alto-stratus and alto-cumulus to cumulus; in autumn very limited cirro-stratus, soon followed by alto-stratus, and frequently alto-stratus alone precede rain. In winter cirro-stratus are not strongly indicative of precipitation, but usually indicate changes in temperature and wind direction; and precipitation is usually preceded by alto-stratus or stratus clouds. In spring and autumn cirrus or cirro-stratus from west to southwest and in summer and winter from west to northwest are sometimes observed two or three days in advance of precipitation.

Frost is preceded by moderate pressure, low temperature, high relative humidity, light winds, and very few, if any, clouds.

Vegetation of all kinds withstands low temperature remarkably well, but frost from September 1 to October 15 would damage forage crops and range grass when there is sufficient moisture to keep them green.

ATLANTA, GA.

In spring and summer the winds which precede rain come most frequently from east, southeast, and south, and the average length of the period which elapses between the time the wind sets in from these directions and rain begins varies from thirty-four hours in spring to seventeen hours in summer. In autumn northeast to southeast winds usually precede rain for an average period of thirty-three hours. In winter rain is generally preceded by an average period of twenty-two hours by wind from the northeast, east, southeast, or southwest, and

snow usually follows after the wind shifts to northwest. In all seasons the barometer generally falls to or below 30 before rain begins and the temperature has been high for the season.

Rain may, as a rule, be expected when the relative humidity exceeds the normal for the season, and the greater the excess the shorter will be the time before the beginning of precipitation.

In spring, autumn, and winter cirrus clouds early in the day, followed by cirro-stratus from the west, usually precede precipitation by ten to fifteen hours. In summer cirrus or eirro-stratus clouds have not been observed, except in thunder-storm formations.

In all seasons the highest winds come from west to northwest, with rising barometer.

In periods of abnormally high temperature the winds are usually from the southwest in spring, from west to northwest in summer, and from southeast to southwest in autumn and winter. During periods of abnormally low temperature, the wind is from the northwest in spring, autumn, and winter, and from east to northeast in summer. Northwest winds are usually dry winds in all seasons.

The general conditions which precede frost are high or rising barometer, temperature 55° and below, low humidity, light to fresh winds, usually from west to north, and clear or clearing weather.

Frost is most likely to damage fruit or other crops during March and April, and cotton during September and October.

ATLANTIC CITY, N. J.

As a rule precipitation is preceded six to twelve hours by easterly winds and falling barometer, except in summer when the wind that precedes showers is usually from south to southwest. In all seasons the barometer generally falls to 30 or below before precipitation begins, and in summer showers occur with the barometer on the turn from falling to rising.

Owing to proximity to the sea and frequent fogs increasing atmospheric moisture is not an indication of rain, except in summer, when an increase in relative humidity is sometimes noticed eight to twelve hours before general rains, and immediately before local rains.

In spring, autumn, and winter the wind increases steadily in velocity until the beginning of precipitation; in summer, however, the wind is usually light before and during local rains, while local rains and thunderstorms are attended by violent squalls.

Cirrus and cirro-stratus clouds moving from the west are often observed twelve to twenty-four hours before precipitation in spring, autumn, and winter, and cirro-stratus clouds one to twelve hours in advance of summer rains.

The highest winds generally come from the northeast with falling barometer. During periods of abnormal heat the wind is westerly in

summer and autumn, and southwest in spring. In all seasons the cold winds are from west to northwest.

Garden truck is likely to be damaged by frost in April, May, and September.

Heavy frost is usually preceded by rising barometer, falling temperature, light variable winds, and few if any clouds.

AUGUSTA, GA.

In spring, summer, and autumn precipitation is usually preceded twelve to twenty-four hours by south to east winds and falling barometer, and in all seasons the barometer generally falls to 30 or below before rain begins. In summer showers occur under varying barometric conditions.

In all seasons, except summer, there is a decrease in relative humidity about twelve hours before precipitation begins; in summer the relative humidity increases about four hours before rain begins. During spring strato-cumulus, and in autumn and winter altostratus, clouds usually indicate precipitation. Cirrus clouds, moving from the west, are often observed twenty-four hours before rain in spring, and ten to twelve hours before rain in autumn and winter. In summer cirrus clouds from west to southwest often appear two to four hours before rain. In spring, stratus clouds moving rapidly from north to northeast; in summer, strato-cumulus moving rapidly from east to southeast, and in winter, alto-stratus moving slowly from west, presage precipitation.

During periods of abnormally high temperature the wind is from the south in spring, from the northeast in summer, and from the southeast in autumn and winter. During periods of abnormally low temperature the wind is from north in spring, from west in summer, from northeast in autumn, and from northwest in winter.

Heavy frost after rain in the last decade of October will seriously injure the cotton crop; a heavy frost in the middle and latter part of April will damage the peach crop.

The general conditions favorable for frost in spring are rising barometer, temperature 40°, relative humidity 60 per cent, north wind, and cirrus clouds. In autumn and winter rising, followed by falling and low barometer, temperature 500, relative humidity 50 per cent, west to northwest winds, and cirrus or cirro-stratus clouds.

In spring, autumn, and winter precipitation is preceded twenty-four to forty-eight hours by southeast winds and falling barometer; rain that falls in summer storms generally comes with rising barometer. In all seasons, except winter, the barometer falls to 29.85 or 29.95, or