I know several people who in various conditions do lock only the front. Mine is still stock so can only lock the rear, or both. Can't lock only the front with the present electronics. Your Sahara likely has Dana 44 rear and Dana 35 front, making the front a little lighter duty. But, with snow and mud, should not be a problem. Might affect stearing and driving so need to exercise some caution.
Could be fun and will be interesting to hear from those who know more about it.
"Take nothing but memories,
leave nothing but 'light tread marks'."