A HISTORY OF HERTFORDSHIRE 



TABLE VII 

 MEAN RAINFALL IN EACH DISTRICT, WITH ITS RELATION TO COUNTY MEAN 



During the last half-century there have been falls of rain of at least 

 z\ inches in twenty-four hours on twelve occasions. On the lath of 

 July, 1889, such a fall occurred at eighteen stations out of thirty then 

 recording, and at least 3! inches at four of these. Falls of at least 3 

 inches have occurred on seven occasions, and of at least 3! inches on 

 30th June, 1878 ; I2th July, 1889, the day with the greatest average 

 rainfall at all stations ; and iyth July, 1890, the day with the greatest 

 fall of rain at any one station, viz. 4' 19 inches at Moor Park, Rick- 

 mansworth. 



Two other elements of climate, viz., sunshine and wind, remain for 

 consideration, but can only be very briefly noticed. The following are 

 averages for the twelve years 1887-98 for wind at Berkhamsted, St. 

 Albans, and Bennington, and for sunshine at Berkhamsted only. 



The prevailing direction of the wind is from S.W. (sixty-one days 

 in the year) to W. (sixty-two days), and the next most frequent winds 

 are N. to N.E. and S. (each about thirty-seven days). The least frequent 

 are S.E. (twenty-five days). About forty-four days in the year are re- 

 corded as calm. March is the most windy month, June the calmest. 



The duration of bright sunshine is least in December and greatest 

 in May; December having rather more than an hour a day, and May 

 nearly six and a half hours. Throughout the year the sun shines 

 brightly for nearly four hours a day. 



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