Problem Weather Display/Ultimeter 2100

it sounds like the raw barometer reading coming into WD is out of range (and so WD ignores the reading)
you could try adding a barometer offset to WD
you should be able to set WD to show the raw barometer reading…
in WD go to setup, advanced/misc, then tick to log the raw data

then under view, debug info, see if the raw barometer reading shows up?