72 



J. HOPKINSON METEOROLOGICAL OBSERVATION'S 



The mean temperature of tlie year was very low, and the mean 

 daily range of temperature was small. There were no high 

 maxima, the extreme being 79°-6, in September, but in December 

 the low minimum of 11°"8 was reached. The temperature was not 

 nearly so variable as in the previous year, every month from 

 January to August being cold, except June which had about a 

 normal temperature, while each month after August was warm, 

 except November which had about a normal temperature. The 

 mean daily range of temperature was less than the average. The 

 mean pressure of the atmosphere was a little above the average of 

 the ten years 1877-86 at Watford. The lowest pressure recorded 

 at 9 a.m. was 28-538 ins. on 11th November, and the highest was 

 30-338 ins. on 18th February, giving a range of 1-800 in. The 

 rainfall was a little above the average of the ten years 1877-86, 

 but much above the average of a long period, these years having 

 been unusually wet ones. February was unprecedently dry ; 

 October, on the other hand, was excessively wet. Rain fell on 

 an unusually large number of days. The air was very humid, and 

 the sky was cloudy. There was a greater preponderance of N. and 

 W. winds, and a less preponderance of easterly winds (N.E. to S.E.), 

 than usual. 



In the winter of 1890-91 (Dec. to Feb.) the mean pressure of 

 the atmosphere was very high, the mean temperature was very 

 low, with a considerable mean daily range, and the rainfall was 

 very small. In the spring (March to May) the mean pressure was 

 nearly the average, the mean temperature was low, with a small 

 mean daily range, and the rainfall was rather small. In the summer 

 (June to Aug.) the mean pressure was about the average, the mean 

 temperature was low, with a small mean daily range, and the 

 rainfall was heavy. In the autumn (Sept. to Nov.) the mean 

 pressure was rather low, the mean temperature was rather high, 

 and the rainfall was heavy. In each season except the winter 

 the air was humid and rain fell on a large number of days ; in the 

 winter the air was rather dry and rain fell on very few days. In 

 the spring, summer, and autumn the sky was cloudy. 



The deviations in each season from the means of our period are 

 as follows : — 



Difference in 1890-91 from Means of 1877-86 at "Watford. 



