Same with me today, on an iMac 5K running 10.11.5. 4GB graphics card. Seemed to be OK since I installed 3.2 of SkyMaxx Pro (with RWC). I use X-Plane's weather.
I was flying along (and had been for half an hour) when the sim crashed. I was on PilotEdge. The sim repeatedly refused to start without crashing. I restored the "output" folder from Time Machine, but that didn't help. Then I looked at log.txt and saw the crash was from SkyMaxx, after parsing the weather. I deleted metar.rwx and the sim started OK. After a minute or two, it crashed again. Running it after disabling real weather was fine.
Maybe X-Plane is currently downloading some corrupt weather, as we are all complaining at a similar time. Or something, somewhere, is not parsing the reports from NOAA or X-Plane's source. Very odd. After all, 3.2 was installed several days ago, and has been stable up till now.