I learned in 2010 that Malmo's citation of weather conditions at the municipal airport will always trump my own observations, even if I'm alongside the marathon course, in T-shirt and shorts, running a nice sweat at 8:30am.
But look at how all the great 5000m runners other than Kipchoge and Chepkok fared in Doha last May. Imane Merga (PB 12:53) actually ran far better than most, with a 13:05. Mark Kiptoo (also 12:53 in 2010) ran 13:34!
Just as striking are all the DNFs. Two or three (Boulahfane, Birgen, and Simotwo) are pacers, but the other three (Gebremeskel, Bekele, Abdosh) were in top 5000m racing shape in 2010, and showed it in the other DL meets. How often do you see three top competitors drop out of a relatively short track race, when even a sixth- or eighth-place finish could gain them points toward a Diamond League crown?
Finally, no PBs in this race except Chepkok (for whom the conditions apparently were ideal), Boujattaoui (whose performance has been DQd by the IAAF, he tested positive for CERA at WXC earlier last spring), and Abera Kuma (13:20 - I'm guessing it might have been his first track 5000m in Europe).
To me, nearly all signs point to less-than-ideal conditions. (Admittedly, I couldn't find mid-race splits, so I'm open to the possibility that an unrealistic, sub-12:50 early pace, *combined* with high temps, caused the slow times and DNFs.)