WEATHER SUMMARY.

Otago Witness, Issue 3882, 7 August 1928, Page 29

WEATHER SUMMARY.

THE MONTH OF JULY.

EXCEPTIONALLY LIGHT RAINFALL

The rainfall in Dunedin during the month of July, as recorded at. the Musselburgh pumping station, was considerably below the average for the second month of winter, the total fall for the 31 days being only ,91in. > This was the lightest ■rainfall registered for July during the past six or seven years, and was onlv a shade heavier than the fall for May last and 12 points less than the fall recorded for July, 1920. The fall for July last year was 4.69 in, over 31in more than that recorded last month. Kain fell on 12 days of the month, and only on one occasion was the fall fairly heavy. This was on July 9, when the pumping station instruments registered over a quarter of an inch. The only other falls of ;.ny consequence occurred on July 11 and 13, so that there were very light falls on nine days of the month. I’he rainfall was widely spaced, and the month was remarkable for the large number of days of bright sunshine and clear blue skies. The only really unpleasant period was experienced from July 17 to 19, when a strong north-east gale raged, although the atmosphere was line and clear. The last four days of the month were very pleasant, the sun shining brightly from a cloudless sky. The winds were mostly light to moderate from the south-west and north-east, and a number °f days were perfectly calm. , . , following table shows the days on winch rain fell during the month ended yesterday:—

Annual ... 24.25 20.87 35.04 38.53 JULY TEMPERATURES.

Variable temperatures were recorded during the past month. The conditions generally were cold, but a number of days was very mild, especially towards the close of the month. Being mid-winter, cold weather was to be expected. Apart from this, the weather all .through the month was in striking contrast to that experienced in the North Island, where frequent storms and periods of heavy rain were recorded. The average daily maximum thermometer readings were between 40 degrees and 54 degrees, while the average minimum readings were between 34 degrees and 44 degrees. The average readings were several degrees below those recorded during June. On only three days July 4, 10, and 23—the temperature rose above 50 degrees. The highest temperature was on July 4, when 54 degrees were registered, one degree less than the highest temperature recorded for June. On July 10 the thermometer showed 52 degrees, and on July 23 51 degrees. On July' 16, .21, 22, and 24 the thermometer was at the 50-degree mark. The temperature was below 48 degrees on 20 days. The lowest maximum readings ■were on July 17 and 29, when the mercury was at the 40-degrees mark. This was one degree more than the lowest maximum reading for June. The lowest minimum reading was on the last day of the month, when the thermometer registered 28 degrees, this reading - being four degrees below freezing point. This cold temperature was due to a heavy frost on the night of July 30. A very cold snap was also experienced on July 30, when the minimum temperature was 30 degrees. Ou July 3 and 29 the minimum readings were 31 degrees. Low readings were also recorded on July 6 and 16 (32 degrees), July 27 (34 degrees), July 14, 17, and 18 (35 degrees), July 12 and 19 (36 degrees), and July 2 (37 degrees). The lowest readings for June were 29 degrees and 39 degrees, minimum and maximum respectively.

'' The barometer was high and fairly steady during the first three days of the month. The reading on the evening of July 2 was 30.20, and 24 hours later it registered 30.00. During the next two days the barometer feH- very rapidly, the reading on the morning of July 5 being 29.75. Atmospheric conditions changed considerably that day, as the barometer showed 29.90 at 5 p.yi. It reached the 30.06 mark on July 6, and then fell very rapidly, being as low as 29.30 on the evening of July 9. Variable conditions prevailed on July 10. as the barometer rose to 29.56 on th§ morning of that day, but was as low as 29.38 in the evening. During'the next three days the readings were again variable, being between 29.55 and 29.80. Unsettled conditions on July 14 and 15 caused the barometer to rise rapidly. From 30.04 it rose to 30.39 on the morning of July 16. This was the highest reading recorded during the month. A dry and stormy period prevailed from July 17 to July 19, and the barometer readings were high during those days. A rapid fall was rioted on July 20, and also on July 21, the barometer being as low as 29.54 on the evening of the latter date. Between July 22 and 27 the readings were between 29.66 and 29.96. The barometer rose to 30.01 op July 28, but the readings varied considerably during the next three days.

CENTRAL OTAGO. - X OPHIR, August 1. The report of the Ophir Meteorological Station for the month of July, 1928, is as follows: — - Average reading of barometer at 9 a.m., 29.88 in; highest (16th), 3t).4liri; lowest (9th), 29.39 in; extreme range, Ro2in. < ‘

Average shade temperature at 9 a.m., 34.1 deg; highest (12th), 48.6 deg; lowest (19th), 23.9 deg; average for June, 33.2 deg; for July, 1927, 32.5 deg. Dry bulb shade temperature: Average maximum, 46.0 deg (July, 1927,43.4 deg) ; average minimum, 27.7 deg (July, 1927’ 25.1 deg) ; approximate mean, 36.8 deg (July, 1927, 34.3 deg). The extreme maximum was 56.9 deg on the 12th; the extreme minimum, 18.3 deg on the 19th. The corresponding figures for July, 1927, were: Maximum, 51.8 deg; minium, 8.7 deg. Average dry bulb and wet bulb: 9 a.m., dry, 34.1 deg; wet, 33.1 deg; 2 p.m., dry, 44.9 deg; wet, 41.2 deg. Mean relative humidity: 9 a.m., 90 per cent.; 2 p.m., 70.5 per cent, of saturation. Minimum grass temperature: Average, 22.9 deg (June, 23.4 deg; May, 26.1 deg) ; highest, 31.5 deg on 26th; lowest, 12.3 deg on 19th. (In June, highest 40.9 deg on 6th; lowest, 10.6 deg on 26th). The temperature fell to 32.0 deg and lower on all 31 mornings (June, 29 mornings). Maximum solar radiation: Average, GS.ldeg (June, 66.8 deg) ; highest, 79.5 deg on Ist; lowest, 46.3 deg on 29th/ Average clearness of sky: 9 a.m., 52 per cent.; 10 p.m., 51 per cent. Wind, recorded at 9 a.m.: Calm, 25 days; N., one day; N.E., two days; S.W., two days; N.W., one day. The average force on these occasions was one to five miles per hour. Rainfall: 4th, 4 points; 7th, 1 point; Bth, 44 points; 10th, 7 points; 11th, 27 points; 21st, 5 points. Total, 88 points on six days. Average in July for four preceding years, 65 points on seven days. Rainfall from January 1 to July 31, 9.01 in on 51 days. No snow fell.

Fog occurred on three mornings, mist on three days, hoar frost on 12 mornings, rime on one morning (31st). Lightnning, without thunder, was seen on the evening of the 12th. General remarks: Barometer very unsteady. Day shade temperatures comparatively mild, the first 15 days of the month average 7.ldeg higher than the last 15 days of June respectively, 49.4 deg and 42.3 deg. There was a distinct drop in average temperatures during the latter half of the month. Maxinum, dry, from 49.4 deg to 43.4 deg; minimum, dry, from 29.3 deg to 26.3 deg; grass minimum, from 24.4 deg to 21.5 deg; 2 p.m., dry, 47.4 deg to 42.5 deg. Though the average precipitation was above the average, there was a remarkable absence of snow, except above 3500 ft altitude on the Dunstan Range. The period from 21st to 30th was unusually cloudy, the ‘average cloudiness being:" 9 a.m., 84 per cent,; 10 p.m., 67 per cent.; the remainder of the month was oppositely clear, with 32 and 27 per cent, of clqud respectively.

July 4 02 July 15 .09 July 5 05 July 16 .01 July 9 36 July 23 .02 July 11 U July 24 .02 July 13 13 July 14 .. .. .04 July July 25 27 .02 .04 . “ e following table gives the monthly rainiail figures for the past five years — 192-1 1925 1926 1927 1928 January ... 1.83 .76 2.08 2.35 1.27 “February ... 1.22 1.71 5.7 3.43 2.45 March ... .37 3.96 .78 4.04 1.80 April ’ 1.82 May 2.9G 2.10 1.48 1.28 5.44 2.7G 2.86 3.77 .83 June 2.72 2.0G 1.24 2.10 1.86 July 2.08 3.84 1.3 4.69 91 Augjjst ... .32 4.6G 3.15 3.6 September ... 1.27 2.1G 2.00 3.73 October ... 4.68 2.01 4.51 3.56 November ... 1.22 3.10 3.18 2.62 December ... 2.76 2.09 4.68 2.89