Arizona republican., 1906-09-19
THE WEATHER BULLETIN
Directors Report for Week Ending
 September l7, I9O6.

Low temperatures prevailed during the entire week. There was a slow de- crease in temperature from Tuesday until Friday, and a very rapid decline on Saturday and Sunday. when the readings were generally s degrees to I6 degrees below the daily normals. The weekly mean temperature for -he Ter ritory was ' degrees below the normal For the northern counties the depart ure was -S degrees; for the central counties. the departure was - de- grees. and for the southern counties the departure was - degrees The temperature reached the freezing point at a few stations over the northern counties. Light frost formed over Yav- apai, Gila and the northern part of Mar icopa counties, and heavy to killing frosts over the northern counties on Sunday morning. The day tempera- lures ranged from 5S degrees to 7S de- grees over the northern section: from A degrees to 100 degrees over the central section, and from 7S degrees to 1O4 degrees over the southern section The extreme temperatures were as fol- lows: At Flagstaff. the maximum tenn perature recorded was 75 degrees. on the 12th; the minimum temperature was 34 degrees. on the 12th. At Phoe-
 
 degrees. on the 12th: the minimum was 56 degrees, on the 18th. At Yuma. the maximum temperature was 1OI de- grees, on the 18th: the minimum was 5S degrees on the 16th.
 Tuesday and Wednesday were clear Light showers occurred over the north ern and few scattered points of the central and southern counties. on Thursday. Friday and Saturday. Over the extreme southwest portion of the Territory. the skies were cIoudIess during the entire week The average number of clear days was five partly cloudy days, 2 and cloudy days. none. 4 severe hailstorm occurred at Tucson on Thursday afternoon The hail fell heavily for about three minutes. and wrought considerable damage to vege- tation in that vicinity The winds blew strongly from the southwest and west. accompanied by frequent sand storms, on Friday and Saturday. At Flagstaff, the wind attained a maxi mum velocity of 32 miles per hour from the southwest. on Saturday morn ing The prevailing ind-directions and the average hourly wind-velocities were as follows: Over the northern counties. the prevailing wind direction was southwest. and the average wind velocity, 6 miles per hour: over the central section, northeast. miles per hour; over the southern section. south west, 3 miles per hour Weekly pre- cipitation was reported as follows: At Flagstaff O-30 inch being a deficiency of 0-20 inch; at Phoenix. GOO inch. a deficiency of O.14 inch; at Yuma O.OO inch. deficiency of 0.G7 inch. The relative humidity of the air was much lower At Phoenix, the weekly mean humidity was 2S per cent. or ' per cent lower than the previous week. The average of the daylight humidity was 14 per cent; the average of the night humidity was 43 per cent The great est humidity was 6S per cent. on tne 18th; the least humidity was per cent on the 18th
 Although there has been a steady de- crease in the flow of water within the river beds of the Territory. there yet remains a large and unlimited supply for irrigation purposes. The run-Off, produced by the light rainfall of the