Probably redundant (and if so mods may delete this) but the 22z HRRR is a significant shift north, and it is still snowing at the runs end. Likely would amount to 2-2.5" in DC.
21z HRRR might be the first run of the HRRR such that the entire storm is within its run. And dare I say the heavier precipitation is more north than 18z.