AT2019wey, which is a black hole X-ray binary, located at: 04:35:23.280 +55:22:34.25,
is currently in outburst in the X-rays. It was originally reported as an optical transient, and should reach about 17th magnitude at peak brightness in red bands, and about 18th magnitude in bluer bands.
Our team (PI Poshak Gandhi at the University of Southampton, and co-PIs Aarran Shaw at the University of Nevada and myself, along with several other folks) have a program approved by JWST to observe any black hole X-ray binary in outburst. We need to get some optical photometry to be sure that it will be bright enough for JWST (we want to do high time resolution, high spectral resolution work, so even with the power of JWST, we need it to be bright).
A single data point verifying that it's optically bright would be a huge help, and then if we can get a lot of different optical filters at the time of the JWST observation, which would probably be a few weeks later, that would help a lot.