An extensive set of flame blowout limit curves has been measured for the case of a hydrogen jet flame surrounded by a heated, supersonic, coflowing air stream and some ideas are proposed to explain the observed trends. The stagnation temperature of the Mach 2.2 air stream was varied from 294 K up to the autoignition temperature of 900 K; hydrogen injection velocities were varied up to 1191 m/s. It was found that the flame blowout curves display two distinct stable regions which are bounded by the: (a) far-field blowout limit and (b) near-field blowout limit. Far-field blowout occurs after a flame first lifts off and is associated with a sufficiently large fuel velocity; the shape of the far-field blowout curve can be explained by previous subsonic lifted flame analyses. Near-field blowout is a sudden blowout for which no liftoff occurs; it results from a sufficiently large air velocity. In all cases the flame attachment point is in the shear layer at a distance of about 1 em from the fuel tube lip.