BJCP 11C
Drier and more hop-oriented that southern English brown ale, with a nutty character rather than caramel.
English brown ales are generally split into sub-styles along geographic lines.
Newcastle Brown Ale, Samuel Smith's Nut Brown Ale, Riggwelter Yorkshire Ale, Wychwood Hobgoblin, Tröegs Rugged Trail Ale, Alesmith Nautical Nut Brown Ale, Avery Ellie's Brown Ale, Goose Island Nut Brown Ale, Samuel Adams Brown Ale
You can view the complete style details on the BJCP website. The 2008 style guide is obsolete but there is a similar 2015 style that you can view below...
OG: 1.040-1.052
FG: 1.008-1.014
IBU: 20-30
SRM: 12.0-22.0
ABV: 4.2-5.4%