ANNUAL WEATHER REPORT FOR 1949 - .20 ANNUAL WEATHER REPORT FOR 1949 The weather for the year 1949

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    ANNUAL WEATHER REPORT FOR 1949The weather for the year 1949 at the Experiment

    Station, Mount Edgecombe, was normal in respectof total rainfall, but, like 1948, 1945 and 1944 inrecent years the distribution of rain was unfavourablein some respects, the months of March and May toAugust inclusive being abnormally dry.

    The mean temperature for the year, 69.1, likethat of. most years with a marked drought period,is appreciably above the 24-year average of 68.7.

    In other respects the weather records for 1949 donot vary greatly from 'the general averages.

    Rainfall.

    The year opened with somewhat deficient rainsin, January, which rather checked the summergrowth of cane. February, however, proved to bethe wettest month of the year, having 6.59 inchesof rain, which was very beneficial for the growingcrops; there was another check to growth duringMarch, which was unusually dry for that month,which has the highest monthly average rainfall here.However, good rains in the latter part of Aprilgreatly improved the condition and prospects of thecrop at that time. .

    In May one of the most severe winter droughtsever recorded here began and continued untiltowards the end of September, the total rainfall forthis period being only 1.99 inches compared with anaverage rainfall of 7.96 inches. During July only0.10 inches of rain fell, on one single day. There were18 days of rain in all during the period, but withnegligible quantities of rain. Thus between May25th and September 7th there was no rainfall of more

    than 0.1 inches. This drought, besides very adverselyaffecting young cane for the 1950 crop throughout,during the latter two months or so began to have amarked adverse effect on the cane yields andmanufacturing qualities of the cane being harvested.

    From September 22nd, when the long droughtbroke, the weather .changed entirely for the remain-der of the vear. Each of the last four months hada rainfall ~ell above the average, the total for theperiod being 19.49 inches against an average of13.57 inches, and from September 20th onwardsthere was no period of more than five consecutivedays without rain, .this giving 61 rain .days out of atotal of 103 days. There were no excessive orinjurious rains and the net result was an excellentplanting season and very good growing weather foryoung cane and for next season's crop.

    The highest rainfall for any single day during theyear was 2.82 inches on April 29th. Other dayswith over two inches of rain were December 1stwith 2.40jnches and February 22nd with 2.04 inches.There were seven days with a rainfall of betweenone and two inches, two in February, one in Octoberand two each in November and December. Next toFebruarv November was the wettest month, witha total of 6.53 inches on 18 davs. The number ofrain days during the year was 115,or slightly belowthe average of 117. The average rainfall per rainday was thus 0.318 inches or very close to the 24-yearaverage of 0.312 inches.

    The total rainfall for the year was 36.61 inches,which is very close to the 24-year average here of36.53 inches.

    Tabulated by' months and compared with averages of the past 24 years, the rainfall is as follows:-

    1949. Mean 19261949 inclusive

    Total Aggre- Per cent. No. . Average Total Aggre- No. Per Averagefor gate of of rainfall for gate of Average cent. of rainfall

    month from 1st average rain per rain month from 1st rain rainfall wet per rain. inches. January aggregate. days. day in ins. in ins. January. days. per day. days. day.

    January 3.05 3.05 79;8 10 0.305 3.79 3.79 14 0.122 45 0.271February ... 6.59 9.64 112.6 12 0.549 4.82 8.61 12, 0.171 42 0.402March. 2.22' 11.80 86.5 10 0.222 5.02 13.63 12 . 0.162 39 0.418April... 3.90 15.76 96.7 5 0.780 2.64 16.27 8 0.088 27 0.330May ... 0.49 16.25 87.6 3 0.163 2.18 18.45 5 0.073 16 0.436June ... 0.56 16.81 82.2 4 0.140 1.84 20.29 4 0.061 13 . 0~460July ... 0.10 16.91 77.7 1 0.100 1.27 21.56 4. " 0.041 13 0.318August 0.21 17.12 74.6 5 0.042 . 1.15 22.71 5 0.037 16 0.230September. 2.45 19.57 78.6 12 0.204 1. 97 24.68 8 0.066 27 0.246October ... 4.72 ' 24.29 86.2 18 0.262 3.33 2~.01 14 0.107 45 0;238November. 6.53 30.82 95.1 18 0.363 4.32 32.33 14 0.144 47 0.309

    . December... 5.79 36.61 100.2 17 0.341 4.20 36.53 15 0.136 48 0.280

    Total... 36.61 36.61 100.2 115 0.318 Mean 36.53 117 0.100 32 0.312

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    Plus OrMaxi- Mini- minus Daily Maxi- Mini- Dailymum. mum. Mean. average. range. mum. mum. Mean. range

    January .. 82.1 60.0 75.2 +1.1 13.1 81.2 67.1 74.1 14.1February .. 80.4 65.0 73.2 -1.4 1~.5 81. 7 67.3 74.5 14.4March .. 80.3 65.3 72.8 -0.2 15.0 80.2 65.7 73.0 14.5April . .. 70.6 62.6 71.1 +1.0 17.0 78.3 62.1 70.2 16.2May .. .. 76.0 55.5 66.2 -0.3 21.4 76.0 56.0 66.4 10.1June . .. 74.0 54.0 64.0 +1.3 20.0 72.8 52.7 62.7 20.1July.. .. 74.3 50.3 62.3 +'0.4 .24.0 72.2 51.7 61.0 20'.5August .. 74.3 54.4 64.3 +0.7 10.0 73.4 53.0 63.7 10.5September. 76.0 58,8 67.8 +2.0 . 18.1 74.6 57.1 65.0 175October .. 75.3 60.7 68.0 -0.4 6',6 76.1 60.8 68.4 15.3November. 77.3 63.1 70.2 -0.5. 14.2 78.1 63.3 70.7 14.8December. 80.5 66.5 73.5 +0.5 14.0 . 80.3 65.6 73.0 14.7

    Means .. 77.7 60.5 60.1 +0.4 18.6 77.1 60.4 68.7 i6.7

    Temperatures.

    The mean screen temperature for the year attheExperiment Station was 69.1, or the same as themean of the past 11 years. Compared with theaverage screen record of the years 1928 to 1938inclusive, which was 68.3, there has apparently beena slight systematic rise in temperature; this ispossibly due to an actual general change in meantemperature as calculated from the mean of thedaily screen maximum and screen minimum tem-peratures, or it may be due to some obscure changein immediate local conditions.

    January was the warmest month of the year andnot February as usual. The mean temperature was75.6, the highest for January since 1944, when alsothe rainfall and number of rain days were belowthe average.

    February was considerably below the averagetemperature, while most of the drought-strickenwinter months were above 'their average tem-peratures.

    There were a rather unusual number of days witha screen maximum temperature of round about100 or over; these being September 19th with 107(a temperature only exceeded once before at thisstation, on December 30th 1941, when it was 113.5),.September 4th with 100.5, November 28th with104.5 and December 18th with 99.5. On the otherhand there was one day, September 7th, with amaximum temperature of 58; it is comparativelyseldom that the maximum does not exceed 60at this station. There was no unusually cold weather;the screen minimum of 43 on July 21st was the low-est for the year and the only time when it fell below47.

    In June a grass minimum thermometer was againinstalled and the. lowest recorded during the yearwas 38.5, also on July 21st. July as usual was thecoolest month of the year.

    Following are the screen temperatures by monthsin degrees Fahrenheit at the Experiment Station,and compared with those of the preceding 21 years.

    1949. 1928.1949 inclusive.

    Atmospheric Conditions.

    The mean true atmospheric pressure for the yearwas 29.76 inches, which is identical with the averagefor this station. June had the highest average forthe year, 29.95 inches, and December the lowest,with 29.60 inches.:

    The maximum barometer reading for the year was30.26 inches on September 7th and October 8th;the lowest was 28.96 inches at 1.45 p.m. on November28th. The latter is the absolute minimum for thisstation; the previous lowest recorded here was29.08 inches in January, 1943.

    The mean relative humidity of the atmosphereper cent of saturation was 75.72 at 8 a.m. and62.91 at 2 p.m. .

    ,These averages are very close to those of thepreceding year; in many respects the generalweather records are remarkably similar to those of1948.

    The most humid months were February, MarchApril and December and the most outstandinglydry month was July with only 66.2percent. humidityat 8 a.m. and 46.7 at 2 p.m.

    The total evaporation for the year from a freewater surface was 46.17, which is slightly belowthe average of 46.57 inches. The highest was 6.19inches, during January as usual, and the lowest2.08 inches for June, also as usual. February,October, November and December were monthswhen the rainfall exceeded the evaporation. Marchis the only month whose average rainfall exceedsthe average evaporation.

    The total hours of sunshine recorded during theyear were 2,437.5, or 55.6 per cent. of the total hoursof daylight, which is slightly above the average forthis station. .

    This year July had the most sunshine, 260 hours,and not Mayas usual; the proportion of sunshineduring hours of daylight was 80.6 per cent., thehighest for any month since July, 1928. November,as usual, had the fewest hours of sunshine, only156.9, or 38.6 per cent. of total hours of daylight,the lowest total for any month since April 1947,though December 1948 had a slightly lower pro-portion of sunshine to hours of daylight.

    Without an anemometer it is not possible toanalyse wind conditions in much detail. Thewindiest months. were January and September,October and November. During the dry months thewinds were mainly from the N.E. to S.E. quadrant,with more southerly winds during rainy periods.There were frequent strong winds, but none ofexceptional violence; on May 17th, October 20th,and November 2nd there were southerly winds of

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    gale force (37,). Hot Berg winds, mainly westerly,were more frequent than usual during the year.June was remarkable for its long and frequent periodsof calm.

    Table of Rainfall and Mean Temperature.

    Rainfall Returns from other Sugar Growing Districts.

    In 1948 the average rainfall from 44 stations.contributing rainfall, records to us was 5 inchesbelow the average, but this deficiency w