Castleford were involved in the only Hunters ECB Yorkshire Premier League North game to beat the weather, but were on the wrong side of the result against Dunnington.
At home to opponents making their return to the top flight, they were in early trouble before a partnership of 67 between Eitan Litvin (31) and new signing Scott Hopkinson (47) got the innings back on track.
However, four wickets for Dave Brent (4-30) and two from Luke Kilby (2-33) saw the hosts dismissed for 162.
Dunnington then kept ahead of the rate to win by the DLS method when play was abandoned with the visitors standing on 107-2.
Castleford enjoyed better fortunes a day later in the National Knockout Cup with a 64-run win over Woodhouse Grange.
Hopkinson’s 92 and 59 by Eddie Cole helped Cas to post a 228-9 total in their 40 overs and Grange were bowled out for 164 with Matthew Rees taking 3-19 and Eddie Morrison 3-32.
Harry Wilkinson hit an unbeaten 111 and Nathan Smith also hit 111 as Castleford seconds piled up 264-1 in 31 overs against Carlton Towers, but they could not complete their York Senior League game with their opponents on 89-4 in 14.4 overs when the match was ended early.