The home side posted 223-5 with Lee Whitfield hitting an unbeaten century (101 not out). Alnmouth were then 212-6 in reply in their 45 overs with Archie Elder on 62 and Thorsten Robinson on 54.
It was local derby day with Alnwick 1sts taking on Warkworth 1sts in Divisiin 2 and it was the hosts who emerged victorious with a big 150 run win.
Alnwick put on 195 all out with James Crooks and Lawrence Reeves both hitting 34. Adam Hall and Kamran Mansoor both took three wickets each for Warkworth, who in reply were reduced to 45 all out with Jim Burston taking 4-13.
In Division 3, Alnmouth & Lesbury 2nds lost be seven wickets at home to Allendale 1sts. Alnmouth were 181-7 with Allendale 182-3.
In Division 5 North, Warenford remain in third following a ten wicket home win over Alnwick 2nds. The visitors were all out for only 62 with Mark Humphreys on 33. Graham Rogerson did most damage with the ball taking 4-8 and Warenford needed only 14 overs to chase it down at 63-0.
Rock hauled themselves off the bottom of the table with a four wicket home win over Monkseaton 1sts. Anthony Lion hit 94 as the visitors posted 211-7, whilst Rock were 215-6 in reply with George Cockayne making a century (116).
Howick went down to a four wicket defeat in a high scoring game at home against Ulgham 1sts. Ulgham were 253-6 in their 40 overs with Robbie Burns on 53 not out. With Andrew Hodgson hitting 94 not out, Howick posted 236-6 in reply.
In Division 6 North, Wooler put on a good score of 248-5 with Angus Todd on 76 not out and Les Porteous on 51. Bomar were all out for 154 in their innings with Matthew Sharpe top scoring on 36, Robert Mathewson taking 3-33.
Embleton are third in the table after a nine wicket home win over Warkworth 2nds. The visitors were 75 all out with Graham Stephenson and Dan Baines taking three wickets apiece. Embleton were 78-1 in reply with Paul Carss on 48 not out.