Commenter Olof R noticed that the TempLS mesh estimate for March had suddenly risen, reversing the previously reported drop of about 0.06°C to a rise of 0.03°C. He attributed the rise to a change in China data, which, as noted in the previous post had been very cold, and was now neutral.
I suspected that the original data supplied by China might have been for February, a relatively common occurrence. Unfortunately when I download GHCN data it overwrites the previous, so I can't check directly. But the GHCN MAX and MIN data are updated at source less frequently than TAVG, and they are currently as of 8 April. So I checked the China data there, and yes, March was very similar to February, though not identical. GHCN does a check for exact repetition.
Then I checked the CLIMAT forms at OGIMET. I checked the first location, HAILAR (way up in Manchuria). The current CLIMAT has a TMAX of -3°C for March and -13.5°C for Feb, and yes, the 8 Apr GHCN has -13.5. So it seems that is what happened, and has been corrected.
So March is warmer than February, and so warmer than any month before Oct 2015. It is also warmer than the record annual average of 2016, and so then is the average for Q1 of 2017. The result is fairly consistent with the NCEP/NCAR average, which showed a very slight fall. I was preparing a progress plot for the next GISS report, so I'll show that for TempLS. It shows the cumulative average for each year, and the annual average as a straight line. 2017 has not started with the El Nino rush of 2016, but is ahead of the average and seems more likely to increase than decrease.