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January, however, has been blessed with genuine cyclonic weather, and has offered biting winds and howling snowstorms fully as invigorating or unpleasant as coastal New England.

SUMMARY OF OFFICIAL WEATHER STATISTICS, JULY-NOVEMBER, 1923 I rather purposely recorded my own impressions of the weather before referring to actual instrumental observations. Thus the impression is subjective, and shows to some degree the reaction of the climate hil on an American. If about 50 Yankees had been experimented with, we might get a fairly accurate impression of the way the climate feels.

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July was drier than normal, with 14 per cent under normal rainfall. August, on the other hand, had 27 per cent over the normal fainfall. September was also very rainy, with 80 per cent over the normal rainfall.

October had 40 per cent over the normal, or 30 mm. more than usual in the rain gauge. Needless to say, log driving and electric power stations were benefited by the high water. During October river driving was completed after one of the most successful seasons known. The temperature was but one degree C. above normal.

November also had a precipitation over the normal, and is reported as one of the stormiest months of the year. Two especially severe storms were reported, and on many days there were high winds along the coast. Despite this, sunshine and cloudiness are given as normal, and the average temperature was 3 degrees C. below normal. Last crops were gathered near Stockholm during this month.

(After deducting for inaccuracy in observation, it will still be noted that I considered November unusually warm, free from storms and sharp changes. One would naturally infer from the discrepancy that November weather in Stockholm is not as violent as in New Haven or Boston, for example.)—H. I. Baldwin, Fellow in Forestry, AmericanScandinavian Foundation.

Central Sweden in Summer (1923)

The whole country is a network of lakes and rivers, well supplied with water, and flowing swiftly. Grain must be dried on elevated racks or under cover. The humid environment above the under foot is reflected in the dress of both men and women. Black rubber raincoats and hats are worn commonly by both sexes; whipcord and cravenetted material is a popular cloth for men's suits and overcoats.-H. I. Baldwin.

WINTER COLD IN CENTRAL NORWAY

The Ostesdal, or eastern valley of the Glommen river, lying in central Norway, farthest from the sea, and surrounded by high mountain tracts, is the coldest part of settled Norway. The moderating influence of the Gulf Stream drift is not felt over a wide plateau of glaciers and alpine

peaks. Down the valley from the north blows a steady, cold, winter wind, never with any great force, but it is fully as successful in chilling the country as the well-known foehn and chinook are in warming their respective lands. This wind is called the "sno" (pronounced snooo). It is interesting to note that its influence is felt only in the valley bottom, 100 ft. rise being sufficient to find calm air and higher temperature. During the season of the year when the sun is lowest, diurnal warming is not great. During the three weeks that I had the pleasure of spending in this crisp weather, there were many days when the temperature did not rise above -30 F. near the river. Up on the valley sides, it was quite comfortable. In skiing down from the high mountains at good speed, however, one had to take precautions against frostbite. Without exception all the inhabitants of this valley, as in many other parts of the country, live along the river, in the very lowest part of the valley, and exposed to the full force of the "sno". The reason for this is purely one of transportation, the roads following the river level. In the summer, when conditions might be considered more favorable in the valley, people move up to "saeters" or high mountain farms near timber line. The reverse of the process would be more logical climatically, or better, a compromise by building on the morainal terraces one or two hundred feet above the valley floor, as is done in Switzerland. The native Osterdalian apparently thrives on the climate, and learns to measure his bodily warmth against the "sno" at an early age. I observed several children, 3-5 years old, out skiing when an accurate thermometer registered -35° F.

The natives do admit that the cold has its drawbacks. For example, extreme cold began about the middle of November this year, and made woods work difficult. All logs must be barked here, and the cold made this hard to accomplish. As workmen are paid by the piece, many found it difficult to earn a living.-H. I. Baldwin.

SWEDISH METEOROLOGICAL SERVICE

The Government Meteorological and Hydrographical Institute (Statens Meteorologisk-Hydrografisk Anstalt) is located at Munkbrogatan 2, Stockholm, on the same island with the palace and the older part of the city. The offices occupy two floors of a large building overlooking the harbor. A fine wireless apparatus enclosed in a fireproof steel cabinet forms part of the equipment, so that weather reports from all Europe and vessels in neighboring waters may be promptly received. A weather map for all Europe is plotted in order better to diagnose Swedish weather conditions. Exceptionally complete reports are received from European stations, the data including cloud forms, height and direction, wind velocity and direction, times of beginning and ending of precipitation, etc., in addition to the usual data on temperature, pressure and precipitation. Forecasting in Sweden is rendered extremely difficult by the mountain barriers along the Norwegian frontier, the presence of large bodies of water, and the various ocean currents in them. Disturbances traveling eastward and southeastward from Iceland often undergo marked alteration in passing from sea to land, and over mountain ranges. Local conditions in the mountains often upset their normal course.

The Meteorological Institute maintains a large number of sub-stations chi (43 2nd class stations, 136 3rd class stations) and employs co-operative observers, many of whom receive a sum of about $200 per annum for their services. In addition to the regular forecasting work, much investigation is carried on by members of the staff. At Abisko, latitude about 68 degrees, 20 min. N., is located a fine seismograph where excellent records were recently obtained of the Japanese earthquake. Inof vestigations to determine the climatic factors controlling the limit of three growth are also under way at this station. Near Abisko some 40 thermographs are maintained at various points along the border of arctic tundra and tree vegetation.

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The library of the Meteorological Office contains over 7000 volumes arranged by geographical units. An interesting feature is the binding of the reports in the national colors of each country to facilitate ready reference. Notable among the library collections is a complete set of the proceedings of the Swedish Royal Academy of Science since 1739. The older volumes are now very rare and contain such names as Celsius and Linneaus who were members of the Academy at that time. The Meteorological Institute is still under the supervision of the Royal Academy.-Henry I. Baldwin.

LOCAL FORECASTING IN SOUTHERN CALIFORNIA *

ald To one who has spent most of his life in the Middle West or the East the progress of the daily winter weather in southern California is not "according to Hoyle." The warmest days come with east winds and clear skies, and the coolest ones with west winds and cloudy skies. The warmest nights, however, often go with the coolest days and the coldest od nights with the warmest days. This apparent paradox is the result simply of the fact that the weather of southern California is usually more strongly controlled by daytime heating by sunshine and nighttime cooling by radiation than by any other factor. When the sky is clear, the air dry, and the wind light, daytime temperatures in winter rise to 75 or 80, and nighttime temperatures fall to freezing or below. A cloudy sky reduces the range by ten or fifteen degrees both at top and bottom, the greatest reduction in range coming when the cloudiness, as is usually the case, is accompanied by moist air and wind. Thus, when a storm is approaching the forecast is, "Cloudy, warmer tonight, cooler tomorrow." And when the storm has passed: "Clear, cooler tonight and warmer tomorrow; freezing temperatures if the wind stops tonight."

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Damaging freezes occur not so much as the result of imported cold air, but because of the nighttime cooling favored by imported dry air. On December 8-10, 1923, when a blizzard raged on the interior plateaus, the heavy gale descending into southern California after passing over the sunny desert was above 60 degrees F. by day. Its extreme dryness, however, with relative humidity down to 24 per cent and dewpoint down to 14 degrees F. indicated the coldness of its source. If the wind had

* Information imparted by H. A. Rathbone in Home Study Course, The Passing Weather, Clark University. Mr. Rathbone is Meteorologist, U. S. Weather Bureau,

engaged in fruit frost investigations and forecasting, Whittier, Calif., NovemberFebruary.

stopped one of those evenings the rapid cooling allowed by the clear dry air would have resulted in a bad freeze. When with a cool wind the day is cloudy and the night clear and quiet the temperature starting down from a maximum of about 50 may reach 20.—C. F. Brooks, in “Why the Weather?" No. 259, Science Service, Mar. 11, 1923.

DRY WINTER IN SOUTHERN CALIFORNIA

Like all California weather, this season has been most "unusual." Without doubt we have just passed through one of the driest winter seasons in local history. Since March 1, 1923, the total rainfall to date, February 8, has been 2.34 inches here at the ranch (Whittier, near Los Angeles, Calif.) In a normal year we should have at least nine inches by this time. Already the extensive drought is making itself felt in the citrus districts as well as on the ranges. The coming summer is bound to be a hard pull on the fruit ranchmen, if much rain is not forthcoming immediately. The snow in the mountains is only about a third of the normal reserve, and if this condition continues, the supply of irrigation water is bound to be short.

This unusual dryness has made itself felt in the daily trend of the passing weather. The lack of moisture in the soil has caused higher winter maximum temperatures than is usually the case, and radiation after sunset has also been more pronounced as a result. In a normal winter, the danger from frost is not very great if the maximum temperature reaches 75°. I would say off hand, that the dry condition of the soil has caused the minimum temperatures to run from two to three degrees lower than would normally be the case with the same maximum temperatures.

Radiation is so great here that the presence of lower clouds during the night immediately dispells all danger from frost. On the other hand our worst freezes generally come the second or third night after a rainy period. The day has been overcast with heavy StCu clouds, and the winds blowing in from the cold interior country to the northward has been cold. The valleys have been filled with cold air and the heavy clouds have not permitted much warming by the sun. At sunset, the wind dies down and becomes calm, due to a lowering pressure gradient, the clouds clear away due to the ending of the wind, and a sessation of local heating by the sun. The maximum temperature has not reached more than probably 50°. As soon as the sky clears radiation is great, and a minimum as low as 22° is not improbable before morning.

The coldest night of the season was that of January 1, 1924. It is se typical of a frosty night that I will give you a description of it.

A high was central over Nevada with a reading of 30.04. A low had moved inland over Southern California and was central over northern Mexico just south of New Mexico. The reading at the center of the low was 29.8. The pressure gradient was not great, but the temperature gradient was very decided. The zero line passed close to Tonapah, Nevada, and the thirty line passed south of Needles, California.

The night of December 31, we had a light shower in the evening, but at 11 P. M. the sky cleared, and the temperature fell to 30° before morning. I found a good many young lemons that were

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frozen on the morning of January first. The cloudiness was very little during the day of the first. Only a few StCu appeared at times during the afternoon, probably due to convection being interfered with by wind. The wind was moderate all day and from the SW. It was unusually cool for a SW. wind. At 5.30 P. M. the wind shifted to the north and increased in velocity owing to the high pressure area gradually becoming dominant over the low. The dew point dropped from 29° at 5 P. M., to 21° at 6.30 P. M. The temperature of this wind during the evening was about 40°. At 10.30 P. M. the wind ceased as suddenly as it began and the air became remarkably calm. The temperature fell very rapidly, and at 11 P. M. it was 26° in the eastern borders of the ranch. The temperature varied from 27° to 23.7° during the remainder of the night.

Here are the dew point and relative humidity figures during the early part of the night.

I have included these data to give an idea of the sudden changes which one must expect when forecasting California weather. The life of a Fruit-Frost man is a continual round of sudden surprises. He must be "on his toes" continually, always ready to forestall any sudden change which is likely to happen. On this night in question I was able to give the growers a forecast which was verified 100 per cent. The forecast was for 25.5° at the key station. This was the actual minimum recorded at that station.-H. A. Rathbone.

Appreciable rains fell in California in March and early April, especially in southern California. Nevertheless, the total up to April 8 was generally but 41-57 per cent of the average from October 1 to that date. Rainfall in per cent of average at selected stations in California, Winter 1923-24.*

* Compiled from Mo. Weather Rev., and Weekly Weather and Crop Bulletin.