The Collaborative International Dictionary of English v.0.48:

Blare \Blare\, v. i. [imp. & p. p. Blared; p. pr. & vb. n.
   Blaring.] [OE. blaren, bloren, to cry, woop; cf. G.
   pl[aum]rren to bleat, D. blaren to bleat, cry, weep. Prob. an
   imitative word, but cf. also E. blast. Cf. Blore.]
   To sound loudly and somewhat harshly. "The trumpet blared."
   --Tennyson.
   [1913 Webster]