The drizzle came and went a number of times as the ground staff did a frustrating dance with the covers.
With the weather brightening 45 minutes before the scheduled lunch, an early interval was called to raise the possibility of an extended middle session if the weather allows.
The tourists are 147 for two in their first innings, still 270 behind South Africa's first innings total of 417 for eight declared.
The West Indies pair of Kraigg Brathwaite (65) and Marlon Samuels (60) will continue their 92-run third wicket stand when play does get under way.
Only six overs were possible on the second day of a Test severely hit by the weather, but they did manage 72 overs on Sunday before bad light brought an early close.
South Africa won the first Test in Pretoria by an innings and 220 runs, with the third and final match to start in Cape Town on Friday.
Image: Covers on at St George’s Park
Photograph: CSA on Twitter
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