Page:Palestine Exploration Fund - Quarterly Statement for 1894.djvu/313

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METEOROLOGICAL OBSERVATIONS AT JERUSALEM.
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July, 11 days; in August, 19 days; and in September, 8 days. Therefore the temperature reached or exceeded 90° on 55 days during the year. At Sarona the first day the temperature reached 90° was on April 30th, it reached or exceeded 90° on only 16 days during the year; the highest temperature in the year at Sarona, 112°, took place on June 15th.

The numbers in column 6 show the lowest temperature in each month; the lowest in the year was 28°5 on March 28th. In January the temperature was below 40° on 22 nights; in February on 16 nights; in March on 18 nights; in April on 10 nights; in November on 7 nights; and in December on 24 nights. Therefore the temperature was below 40° on 97 nights during the year. The yearly range of temperature was 76°·5. At Sarona the temperature was below 40° on only 3 nights during the year; the lowest in the year, 37°·0, took place on both December 22nd and 23rd. The yearly range of temperature at Sarona was 75°. The range of temperature in each month is shown in column 7, and these numbers vary from 28°·5 in January, to 60°·2 in April. At Sarona the range of temperature in each month varied from 26° in August to 55° in June.

The mean of all the highest by day, of the lowest by night, and of the average daily ranges of temperature, are shown in columns 8, 9, and 10 respectively. Of the high day temperatures, the lowest, 53°·9, is in January, and the highest, 92°·2, in August. At Sarona, of the high day temperature, the lowest, 64°·7, is in January, and the highest, 87°·9, in August.

Of the low night temperature, the coldest, 37°·8, is in December, and the warmest, 59°7, in June. At Sarona, of the low night temperature, the coldest, 48°·1, is in December, and the warmest, 69°·2, in August. The average daily range of temperature is shown in column 10, the smallest, 14°·8, is in January, and the largest, 33°·8, in August. At Sarona, of the average daily range of temperature, the smallest, 15°·4, is in January, and the largest, 23°·5, in October.

In column 11 the mean temperature of each month is shown, as found from observations of the maximum and minimum thermometers only. The month of the lowest was December, 42°·0, and that of the highest, August, 75°·3. The mean temperature for the year was 60°·1. At Sarona, of the mean temperature, the month of the lowest is January, 57°·0, and that of the highest August, 78°·6. The mean for the year at Sarona was 66°·8.

The numbers in columns 12 and 13 are the monthly means of a dry and wet bulb-thermometer, taken daily at 9 a.m. In column 14 the monthly temperature of the dew-point, or that temperature at which dew would have been deposited, is shown; the elastic force of vapour is shown in column 15. In column 16 the water present in a cubic foot of air is shown; in December it was as small as 2·9 grains, and in August as large as 5·3 grains. In column 17 the additional weight required for saturation is shown. The numbers in column 18 show the degree