JW:
Critical azimuth (from the POH) is 050 to 210. However, the POH states
Tail rotor control margin and/or control of engine parameters (TOT and torque) may preclude operation in AREA B of the Hover Ceiling charts when the wind is in the Critical Wind Azimuth Area.
On the day, looking at the HOGE chart just to be pessimistic, I was nowhere near AREA B, but was well in the Critical Azimuth - assuming +35 celcius, 1000' pressure alt, and 3200lbs.