NELSPRUIT – Lowvelders are not used to walking around this time of year wearing long boots and thick jackets.
Yet this year it seems that many locals complain that winter has not quite left us. Or has it and we just imagine it is colder and wetter than usual?
The Lowveld has a tropical climate, with warm sub tropical temperatures and it experiences high summer rainfalls. Between the months of September and March this area receives an approximate rainfall of 620mm while the entire Mpumalanga area average a total rainfall of about 1 000 mm a year.
If one takes the historical monthly averages for December the daytime temperatures will generally reach highs of around 30°C. At night the average minimum temperature drops down to around 17°C. For the past few years the highest recorded temperature in December has been 41°C, with the lowest recorded temperature 0°C, which is a very broad spectrum.
Although we might not choose to remember that every December is normally a wet one, and moan that December is our swimming season, statistics prove otherwise.
The average daily relative humidity for December is around 81%. The average monthly amount of precipitation has been recorded at around 160 mm, that’s 6 inches.
Just like this time last year, the local dams and rivers are overflowing with more rain expected.
With the exception of this coming weekend where the sun will peek from behind the clouds for two days, the following week is filled with rain.
Historically the Lowveld during this time of year will vary between being pounded with heavy rainfall to the climate being extremely hot and humid. Using the heat index scientists have been able to record data to indicate how hot it feels when relative humidity is added to actual air temperature. From this a comfort level is calculated providing categories on how heat conditions might adversely affect someone.
Given the Lowveld’s average maximum temperatures and humidity levels caution is advised. Fatigue is possible with prolonged exposure and/or physical activity for those in high risk groups of possible heat disorders. For December expect the sun to shine for an average of six hours per day. This represents the average number of hours in the daytime that the sun is visible and not obscured by cloud e.g. the average number of hours the sun is actually out and shining. Note that this was calculated hours of sunshine per day using past forecast data, not observation data, thus it is an estimate and not actual.
For the past two decades the average daily wind speed in December has been around 5 km/h, that’s the equivalent to about 3 mph, or 3 knots. In recent years the maximum sustained wind speed has reached 28 km/h, that’s the equivalent of around 17 mph, or 15 knots.
At the time of going to print the Witklip Dam had received 56mm of rain on December 2 and 10.4mm of rain on December 9 and is more than 99% full. Kwena Dam received 91.1mm of rain on December 2 and 34.6mm on December 9. The dam is 101% full.
The Da Gama Dam received 65.2mm of rain on December 2 and 60.4mm on December 9. This dam is 93.7% full.
