25 January 2019 at St George's Park: 21 °C, humidity 75%, wind 20 km/h and 1.7 mm of rain during the hours of play. 23 of 430 evenings within three weeks of 17 January in the last 10 years had at least 1 mm of rain at St George's Park during these hours.
These conditions are wet, with 1.7 mm of rain during the hours of play. At SA20 grounds, 37% of games in similar weather were shortened or washed out. Rain is spread across the afternoon and evening, overlapping both innings. Runs lines assume 20 overs. Heat and wind have made no measurable difference to first-innings scoring at SA20 grounds.
During play: 20.7 °C on average, humidity 75%, wind 20 km/h gusting to 45. Humidity climbs from 65% to 87%; at SA20 grounds, chasing success hasn't varied with humidity.
Runs figures assume 20 overs. If overs are lost, totals and par come down: check how your bookmaker settles runs markets in reduced matches.