Cardiff had to withstand a second half onslaught from Llandovery before running out 9-15 victors at the Dairy Field.
The visitors led 15-3 at the break thanks to five penalties from Gareth Davies but the Drovers used the elements to their advantage to pile on the pressure in the second spell. Outside half Gareth James added to his first half effort with a second half brace of penalties to bring Llandovery a losing bonus point - their first of the season.
Scott Snedden helped himself to 22 points to guide Glamorgan Wanderers to a 27-8 victory against Cross Keys. Outside half Snedden was instrumental in hoisting the home side into a 13-0 lead early in the second half and his try after 72 minutes made victory secure in difficult conditions. Keys just couldn't get into the game and conceded a try to wing Steve Cullen after 15 minutes and found themselves 10 points adrift at the interval. Former Wales Under 21 wing Marcus Johnston grabbed a try back for Keys, but that merely cut the deficit to eight points. Full back Paul Smithson added a penalty, but it was all too little too late.
Pontypool were given a torrid time at the Talbot Athletic ground as Aberavon ran in four tries in a comfortable 29-0 triumph.
Marc Breeze launched the onslaught with the first try and Richard Thomas soon followed. The Wizards were 13-0 ahead at the interval and more than doubled their advantage after the break. Dai Pritchard ran in a brilliant solo try before Ashley Beck grabbed the bonus point.
Llanelli have edged further ahead at the top of the pecking order at brushing aside the challenge of Bedwas 25-8. With nearest challengers Neath suffering a defeat, Luke Richards kicked six penalties to steer Llanelli to their fifth successive win.
Bedwas centre Adam Thomas opened the scoring with a well taken try but it proved a false dawn. Once James Bater peeled off the back of a scrum to score, Llanelli were back in charge just before halftime.
Bridgend ended the longest running winning sequence in the Premiership after clinching their first victory at the Gnoll since 1990 with a 15-16 victory against Neath. The Ravens were out-scored two tries to one but were well worth the win after wrapping up the Welsh All Blacks for the final 20 minutes after Gareth David's crucial kick. Bridgend prop Ryan Bevington caught Neath napping at the start of the second half when he crashed over. But the day belonged to full-back David who kicked 11 points, including what transpired to be the winning penalty on 65 minutes.