1. Ill-humored; churlish in manner or mood; sullen and gruff.
2. Menacing or threatening in appearance, as of weather conditions; ominous.
Maggie drank a little too much and got surly and made snide comments during the final toast.
-- John L'Heureux, Having Everything
Surly is from Middle English sirly, "lordly," from sir, "lord," which eventually came to mean "arrogant or haughty," whence the more negative modern sense.