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There is nothing in this yokel science of bark and beaver. And there is quite as little in the claims of those who use the planetary influences, as any boy or girl of sixteen, studying the average text book in any high school in the country, could tell. But the public loves to be fooled, and in nothing is it fooled so easily as by those who tell the weather to come by the rule of thumb.


This issue of the Monthly Weather Review contains 11 contributions, a few of which are very short, and 24 notes, abstracts, etc., 6 of the latter being on winter weather, and long-range forecasts. Synopses of the contributions follow:


The freezing of rain onto wires, trees, and streets is so disastrous to telephone, telegraph, and power lines and radio-station aerials, to trees, and to transportation facilities that such means as can be employed to combat the formation of ice should be made ready before an "ice storm" begins. This involves forecasting the conditions which will cause the glaze to form, i. e., conditions such that liquid drops of water will fall from a relatively warm wind into cold air near the ground. The occurrence of sleet as well as the formation of glaze usually marks such a condition of the atmosphere and thus is a valuable (and noisy) index to glaze formation.

While the form of the precipitation reaching the earth's surface allows a fairly accurate surmise to be made as to critical temperatures aloft, actual observations by means of kites or airplanes, taken in conjunction with observations made at the surface, offer the best basis for "ice-storm" forecasts.

The first article indicates the general conditions under which sleet (and glaze) is formed, and the second discusses the actual meteorological features accompanying the storm of January 20 to 25, 1920, long to be remembered for the great destruction and inconvenience caused by the thick ice which formed over hundreds of thousands of square miles in the eastern United States.

The nature of sleet and how it is formed. C. F. Brooks. (pp. 69-71, fig.) [AUTHOR'S SYNOPSIS.-Whereas in current practice in the United States, sleet is that form of precipitation which is not snow, rain, nor hail, an attempt to make a detailed descriptive and genetic definition seems advisable, and 30 cases of sleet are analyzed as a basis:

Sleet, a rattling type of ice precipitation formed in the free air, has the following characteristics: Size, smallest dimensions of largest pieces less than 6 mm. (1/4 inch); form, angular, irregular, or nearly spherical; structure, non-granular ice, part or all of which is cloudy or bubbly, except in extremely small drops, not more than one clear layer.

A sleet particle may be (1) a snowflake, partly melted and refrozen, (2) a frozen raindrop, or (3) a frozen combination of snowflake, and raindrop or liquid (not undercooled) cloud droplets.

A generalized vertical section of sleet weather shows that sleet usually occurs with a cloud from which snow is falling through a stratum of air having a temperature above freezing and into air with a temperature below freezing.]

The precipitation of sleet and the formation of glaze in the eastern United States, January 20 to 25, 1920, with remarks on forecasting. C. L. Meisinger. (pp. 73-80, 18 charts.)

[AUTHOR'S SYNOPSIS.-An attempt is made, by means of accurate charts of precipitation during the previous 12 hours, current temperature, pressure, and lines of wind flow, in combination with such aerological data as could be obtained, to construct cross-sections of the lower 3 kilometers of the atmosphere, during the period January 20 to 25, 1920. From such charts are shown the actual processes which produce rain, sleet, and snow, separately and in combination, in such a manner as to produce the ice cover, which is called an "ice storm." The condition is, briefly, a cold northerly wind underrunning a warm southerly current, forcing the latter aloft. The vertical distribution of temperature,

shown in the cross-sections, indicates the manner in which the isotherms over the territory covered by the northerly wind rise normally until the level of the overrunning southerly wind is attained, where the isotherm swerves sharply northward. The distance that the isotherm of freezing reaches is indicated by the northern limit of the precipitation of sleet.

An empirical relation was obtained between the distance from the wind-shift line to the 32° isotherm and (1) the width of the glaze belt, (2) the width of the sleet belt, (3) the distance of the center of the sleet belt north of the 32° isotherm, (4) the width of the glaze belt on a meridian 4° east 12 hours later, and (5) the width of the glaze belt on a meridian 8° east 24 hours later. These values are presented with the full realization that they may be true for this particular storm only, and are as follows:

(1) The width of the glaze belt

the wind-shift line.

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(2) The width of the sleet belt = 0.7 X the distance between the 32° isotherm and the wind-shift line.


0.9 X the distance

(3) The distance between the 32° isotherm and the center of the sleet belt = 0.8 X the distance between the 32° isotherm and the wind-shift line. (4) The width of the glaze belt 4° east, 12 hours later between the 32° isotherm and the wind-shift line; and (5) The width of the glaze belt 8° east, 24 hours later = 0.8 X the distance between the 32° isotherm and the wind-shift line.

The importance of the wind-shift line in forecasting the region over which sleet or glaze are likely to occur is strongly emphasized, since it marks the line of ascent of the southerly wind and hence is the basis upon which rests the location of this type of precipitation.]

Note on deep northeast-component winds observed January 27-31, 1920. S. Gottlich. (pp. 81-82, 10 figs.)

[In the central and southern United States, during the period immediately following the long sleet-storm there were winds from the northeast to great heights. Stereoscopic views of weather maps with wind-arrow posts for the winds aloft show conditions on the 27th, and again on the 30th to 31st accompanying the arrival of a sudden cold wave in the northeastern United States. These last maps showed the arrival of the cold northerly and northeasterly winds in the lower levels only, as is characteristic of such cold waves.]

Blizzards and chinooks of the North Dakota plains. F. J. Bavendick. (pp. 82-83.)

[A very graphic description of blizzards is given, and the shallow depth of the winds is shown by kite flights. Chinooks may blow aloft at a moderate elevation without affecting the surface.]

Note on the meaning of "Blizzard.”—So far as known, this term was first used in the middle western United States to describe a type of winter storm of rather frequent occurrence in that region, characterized by (1) high wind, (2) very low temperature, and (3) an abundance of fine snow in the air. The etymology of the word is still speculative. A plausible hypothesis traces its origin to the German word blitzartig ("lightninglike"), said to have been applied to these storms by early German settlers in Dakota.

There is a tendency, both in the United States, and in other English-speaking countries, to apply the word “blizzard” indiscriminately to any heavy snowstorm accompanied by more or less wind. Some remarks pertinent to this subject, by Bostwick, Dines, and Bonacina will be found in Nature, volume 97, 1916, pages 261, 280 and 301. This broad use of the term impairs its utility for purposes of exact description, and should be discouraged.

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It is doubtful whether true blizzards, characterized by intense cold, high wind, and blinding clouds of dry, powdery "snowdrift,' ever occur in the British Isles, and they are excessively rare in the eastern United States. They are not, however, peculiar to the interior of the American Continent, for the most intense storms of this character heretofore recorded are those of Adelie Land, Antarctica, so graphically described in Sir Douglas Mawson's "Home of the Blizzard" (London, 1915).-C. F. Talman.

Weather forecasting. H. H. Clayton. (pp. 83–84, 3 figs.) [Discusses the Bjerknes papers on forecasting (Feb. 1919, Mo. pp. 95-99) and goes into history of stream-lines on weather maps.

Weather Rev.,
Mr. Clayton

makes stream-lines more from the isobar trends than from the locally varying surface wind directions. On lines of convergence, rainfall is necessarily to be expected because of the forced ascent of air.]

Relation of winds to temperature in central Ohio. H. H. Martin. (pp. 85-86, 2 figs.)

[AUTHOR'S SYNOPSIS AND CONCLUSION.-This paper presents by table and graph the existing relation between the direction of the wind and the existing or current temperature, as well as the subsequent 24-hour temperature change. The data are taken from the records of the Columbus (Ohio) office, 1909-1918, inclusive.

Under ordinary conditions, at Columbus, Ohio, it seems safe to consider the north, northeast, east, and southeast winds as prognostics of warmer weather 24 hours later, except in summer, when the east wind has no prognostic value; and the northwest, west, southwest, and south winds as prognostics of cooler conditions 24 hours later, except in summer, when the northwest wind is usually followed by higher temperatures. However, excepting the case of the east wind in winter, the true prognostic values are low and do not justify much reliance. Their value would be appreciable only when used in conjunction with other indications.]

Altitude determinations based on barometric readings. H. G. Cornthwaite. (pp. 87-88, 2 figs.)

[Under favorable conditions very accurate (max. error ±1%) altitude determinations can be made from simultaneous barometic readings, especially in the Tropics where air-pressure fluctuations are small. Up to elevations of 5,000 or 6,000 feet a mercurial barometer is preferable to an aneroid for this work if closely accurate results are desired.]

Comparison of snowboard and raingage-can measurements of snowfall. R. E. Horton. (pp. 88-89, fig.)

[Measurements of depth of snowfall on a white-cloth covered board kept flush with the surface of the snow are 16% greater than those obtained with the usual raingage with snow attachment.]

On the comparison of meteorological data with results of chance. L. Besson. (Translation.) (pp. 89–94.)

[In a set of N daily values of a meteorological element, e. g., pressure, it is desirable to be able to tell whether the n minima and m maxima are the results of some physical cause which always tends to produce n minima in N days, or whether they are merely random occurrences. Besson derives formulae giving the number, sizes, and distribution of the minima in a series of N numbers resulting from pure chance selection.-E. W. W.]

Influence of the wind on the movements of insects. W. E. HURD. (pp. 94-98.)

[For most insects wind is a highly important factor in ordinary movements and in the dispersal of insects and their invasions of new territory.]

Limited editions of reprints are being made for the sleet papers, and for those by Messrs. Martin, Besson and Hurd. Applications for any should be made to "Chief, U. S. Weather Bureau, Washington, D. C."


Vortex Motion in the Atmosphere.-To a recent inquiry, the Weather Bureau made the following reply:

Not much has been added recently to "the theory of vortex motion and its application to the analysis of local cyclones, anticyclones, thunderstorms, etc." One of the fullest discussions we have of vortex motion is given in Lamb's "Hydrodynamics."

This discussion applies, roughly, or with proper limitations, to the tornado. It does not apply, however, to the cyclone, except, possibly, to the small tropical cyclone, and to it but very roughly, because the average cyclone is only slightly vortical. Still less does it apply to the anticyclone; and scarcely at all to the thunderstorm.

Some of the recent discussions of more or less local revolving storms are by:

Shaw, Sir Napier:

12, 1918.

Geophys. Memoirs, Gr. Brit. Met. Office, London, No.

Shaw, Sir Napier: A. 94, p. 34, 1917. Shaw, Sir Napier: Jeffreys, Harold: Phil. Mag., V. 37, p. 1, 1919.—W. J. Humphreys . Sleet Storm Brings Starling Invasion.—One of the interesting effects of the recent sleet storm, in Washington, D. C., was the arrival of thousands of starlings, which have, heretofore, been seen only in very small numbers in and about the city. The sleet storm, however, brought great numbers, which, according to the Washington Star of March 15, 1920, “had for (their) immediate objective the back yard garbage cans hitherto held in security by the starling's compatriot, the English, or house, sparrow."

"Revolving Fluid in the Atmosphere," Proc. Roy. Soc., "Manual of Meteorology," Part IV.

The Cold Winter of 1919-1920 in the Eastern United States.-The National Weather and Crop Bulletin (Weather Bureau, Washington, D. C.) for April 20, 1920, contains an interesting chart of the departure of mean temperature from the normal, December 1, 1919 to February 29, 1920, in the United States. The temperatures were more than 6 degrees F. below normal in much of the Lake region, and more than 4 degrees below normal in most of the country east of the Mississippi and north of the Ohio rivers and 40th parallel of latitude. The Gulf States and the Great Plains were warmer than normal, but not much so. The departures in the West were generally plus in the Southwest half and minus in the northeast half. Another chart shows the lowest temperatures of the winter.— C. F. B.

Mr. Frederick H. Brandenburg, meteorologist, in charge of the Denver office, died in that city on April 17, 1920.

Mr. Brandenburg was born in Washington, D. C., on August 23, 1854, and enlisted in the Signal Corps on August 21, 1877. All of his 43 years of service was in Colorado, with the exception of 3 months' training at Fort Whipple, I year as assistant at Chicago, and 31⁄2 years as clerk in Washington. He was transferred from Washington May 5, 1882, to charge of the station at Las Animas, Colo., where he served until June 1, 1888, thence to charge of Pueblo until June 7, 1894, when he was placed in charge of the Denver office. When the Denver forecast district, comprising the States of Colorado, Utah, New Mexico, and Arizona, was organized in 1901, he became the official forecaster for that district. Mr. Brandenburg had been in poor health for several months, but he remained on duty until noon, January 5, 1920, when he was stricken with paralysis and taken to his home. He was unable to resume his work thereafter.-Weather Bureau Topics and Personnel.

WEATHER OBSERVER NEEDED ON ISTHMUS OF PANAMA. Mr. A. L. Flint, Chief of Office, The Panama Canal, Washington, D. C., has communicated the following:

This office has received by cablegram an urgent requisition from the officials on the Isthmus of Panama for the appointment of an observer at an entrance salary of $137.50 a month, with prospects for promotion to $150.00 a month. The appointee will be furnished with free steamship transportation from New York or New Orleans to the Isthmus, wages beginning on date of sailing. A man is desired who has had at least one or two years' experience in weather bureau observation and form work, and the appointee is required to sail as early as possible. The appointee will be furnished with free bachelor quarters on the Isthmus, including light; also free medical and hospital attention, and meals can be secured at the Government restaurants for 40 cents each and upward. Annual leave

with pay up to 61 days may be allowed. He should be an American citizen under 50 years of age, and in good health.

The Weather Bureau was appealed to without success, for, to quote from a letter from the Chief, Prof. C. F. Marvin:

"The condition of the personnel in this Bureau is somewhat critical at the present time, as we have had big demands on the younger men of the service through the Signal Corps of the Army, the Navy Meteorological Service and other sources. We are having considerable difficulty in recruiting our service from men available in commercial lines at the present time, as indicated by the certificate just received from the Civil Service Commission for assistant observers which gives the eligibles secured from the December examination as only four in number, two of whom are already serving temporarily in our service."

For further information and application blanks, address "Chief of Office, The Panama Canal, Washington, D. C."


The United States Civil Service Commission announces an open competitive examination for assistant observer, Weather Bureau, on May 19 and July 21, 1920. Vacancies in offices of the Weather Bureau throughout the United States, and in positions requiring similar qualifications, at $1,080 a year, or higher or lower salaries, will be filled from this examination. Appointees whose services are satisfactory will be allowed the bonus of $20 a month granted by Congress. All citizens of the United States who meet the requirements, both men and women, may enter this examination. For this position in the Weather Bureau male eligibles are desired. Persons who are unable to accept appointment at a distance from their places of residence, or who would be unwilling or unable to transfer to other stations where their services are required after appointment, because of marital dependents, will not be considered for appointment to this position.

Competitors will be examined in the following subjects, which will have the relative weights indicated:

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Seven questions are given in meteorology, seven in arithmetic, and seven in algebra. The competitor is required to answer five in meteorology, four in arithmetic, and four in algebra. The scope of the subject of elementary physics is equivalent to that covered in a high-school course of one year. The subject of mathematics includes questions in arithmetic similar to those of the first grade and elementary algebra through quadratics.

Applicants must have reached their eighteenth but not their thirty-fifth birthday on the date of the examination. Age limits do not apply to persons entitled to preference because of military or naval service. Applicants should at once apply for Form 304, stating the title of the examination desired, to the Civil Service Commission, Washington, D. C., or to the local Secretary of the United States Civil Service Board.


On page 33 of the March issue of the BULLETIN, the Army Air Service station, Mitchell Field, Long Island was erroneously referred to as a Naval Air Station. The Weather Bureau office in New York City gives meteorological advice to the Naval Air Station at Rockaway Beach, L. I., on occasion.

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