Wording and Verification of Forecasts

To a farmer suffering the effects of drought the word fine seems inappropriate because dictionaries indicate many meanings, most of which connote feelings or assessments of pleasure, although some indicate the meaning of sunny or absence of rain.

Another problem with rain is its spatial and temporal variability. The term showers is generally used by meteorologists to indicate convective rainfall which occurs in patches adjacent to areas in which no rainfall occurs. The problem is further complicated by the difficulty of forecasting exactly where and when rainfall will occur and the amount of rain which will fall.

By contrast the forecasting of temperature is less difficult because the processes which determine temperature are less complicated, although the difficulty of forecasting cool changes and cloudiness can produce problems in forecasting maximum and minimum temperatures.

There is also less difficulty in communicating the idea of what is cold, cool, warm and hot. An idea which developed during the Dwyer years which caused some dispute within the Bureau suggested that the expected maximum and minimum temperature should be included in forecasts. As degrees Fahrenheit were used at that time some Deputy Directors expressed the view that to use such a system was beyond the accuracy with which forecasts could be made. My memory suggests that some of us in Central Office persuaded Len Dwyer to adopt the system, which was used to advantage.

Bureau of Meteorology