General Information Maximum temperature record at Vredendal on 27 October 2015
NOTE: Following a thorough verification process it became clear that the quality-control standard operation procedure (SOP) was not applied correctly, which resulted in the real maximum temperature record of 48,4 °C being removed. It was however recovered from the logger of the automatic weather stations (AWS) and reinstated on the national climate database. The information below was accordingly updated.
On Tuesday 27 October 2015 at 15:54 the temperature in Vredendal reached a new record high value of 48,4 °C. It exceeded the previous highest maximum temperature of 42,5 °C recorded at Vredendal on 30 October 1999.
We do realize the importance of performing a thorough verification of the data measured by the automatic weather station (AWS) at Vredendal in the Western Cape; however, a preliminary investigation of the 5-minute data recorded did not reveal any conspicuous reason to question the accuracy of the data recorded by the AWS before and on the day.
Vredendal - 27 October 2015
Temp Hum
60 70
60 50
50 40
C) 40 ° 30
Temp Temp ( 30
20 20 Relative Humidity(%)
10 10
0 0
00:50 13:35 01:35 02:20 03:05 03:50 04:35 05:20 06:05 06:50 07:35 08:20 09:05 09:50 10:35 11:20 12:05 12:50 14:20 15:05 15:50 16:35 17:20 18:05 18:50 19:35 20:20 21:05 21:50 22:35 23:20 00:05
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General Information Maximum temperature record at Vredendal on 27 October 2015
According to preliminary data from our temperature monitoring network, at least 13 operational weather stations in the Western Cape (Vredendal, Redelinghuys, Wellington, Porterville, Malmesbury, Clanwilliam, Langgewens, Paarl, Robertson, Cape Town Royal Yacht Club, Jonkershoek, Atlantis, and SA Astronomical Observatory) and 5 in the Northern Cape (Vioolsdrif, Augrabies Falls, Niewoudtville, Sprinkbok and Calvinia) recorded new highest maximum temperature records on 27 October 2015, of which all were higher than 38 °C.
The synoptic situation that prevailed on the day caused berg-wind conditions over the western and south-western parts of South Africa. It is not uncommon for extremely high temperatures to occur during berg-wind conditions in South Africa. Furthermore, the relative calm conditions that prevailed in Vredendal throughout nearly the entire day were very conducive for the extremely hot conditions that developed.
Vredendal - 27 October 2015
Temp Wind speed
60 8
7 50 6 40
5
C) °
30 4 Temp Temp ( 3
20 Wind speed (m/s) 2 10 1
0 0
14:20 00:50 01:35 02:20 03:05 03:50 04:35 05:20 06:05 06:50 07:35 08:20 09:05 09:50 10:35 11:20 12:05 12:50 13:35 15:05 15:50 16:35 17:20 18:05 18:50 19:35 20:20 21:05 21:50 22:35 23:20 00:05
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General Information Maximum temperature record at Vredendal on 27 October 2015
The extremely high maximum temperatures that occurred over the Northern and Western Cape on 27 October 2015, are evident on the following map displaying the daily maximum temperatures that were recorded countrywide.
Following is a list of highest maximum temperature records that were recorded on 27 October 2015, of which 18 were above 38 °C.
No of #Parameter Old Old Date New New Date years Station Prov Highest Maximum 42.5 1999-10-30 48.4 2015-10-27 55 VREDENDAL WC Highest Maximum 39.8 2009-10-20 43.4 2015-10-27 7 REDELINGSHUYS-AWS WC Highest Maximum 41.4 1985-10-10 42.4 2015-10-27 52 WELLINGTON WC Highest Maximum 39.6 1999-10-30 42.4 2015-10-27 28 PORTERVILLE WC Highest Maximum 38.6 2014-10-05 41.8 2015-10-27 29 MALMESBURY WC Highest Maximum 40.6 2011-10-09 41.7 2015-10-27 15 CLANWILLIAM WC Highest Maximum 39.9 1985-10-10 41.5 2015-10-27 55 LANGGEWENS WC Highest Maximum 37.4 1999-10-30 41.2 2015-10-27 22 PAARL WC
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General Information Maximum temperature record at Vredendal on 27 October 2015 Highest Maximum 39.5 1985-10-10 41.1 2015-10-27 53 ROBERTSON WC Highest Maximum 37.8 2003-10-12 40.3 2015-10-27 14 CAPE TOWN - ROYAL YACHT CLUB WC Highest Maximum 36.1 1985-10-10 39.3 2015-10-27 55 JONKERSHOEK WC Highest Maximum 38.1 2003-10-12 38.9 2015-10-27 36 ATLANTIS WC Highest Maximum 35.9 2003-10-12 38.2 2015-10-27 55 S A ASTRONOMICAL OBSERVATORY WC Highest Maximum 34 2003-10-12 35.7 2015-10-27 23 ROBBENEILAND WC Highest Maximum 33.4 1985-10-10 34.9 2015-10-27 54 CAPE POINT WC Highest Maximum 44.2 1999-10-30 46.9 2015-10-27 24 VIOOLSDRIF - AWS NC Highest Maximum 42.3 2014-10-26 43.5 2015-10-27 31 AUGRABIES FALLS NC Highest Maximum 36.9 2011-10-09 41.1 2015-10-27 6 NIEUWOUDTVILLE NC Highest Maximum 36.7 1997-10-01 38.4 2015-10-27 28 SPRINGBOK WO NC Highest Maximum 37.2 2000-10-12 38.2 2015-10-27 29 CALVINIA WO NC
Compiled by:
Elsa de Jager Musa Mkhwanazi
Unit Manager: Climate Information Senior Scientist: Climate Information
Date: 11 November 2015
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