Perfect. Thank you! In case the link goes bad I'm posting the relevant info here for future reference:
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MADIS QC Information - Surface
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QC Data Descriptor Values
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No QC available:
Z - Preliminary, no QC
Automated QC checks:
C - Coarse pass, passed level 1
S - Screened, passed levels 1 and 2
V - Verified, passed levels 1, 2, and 3
X - Rejected/erroneous, failed level 1
Q - Questioned, passed level 1, failed 2 or 3
where level 1 = validity
level 2 = internal consistency, temporal consistency,
statistical spatial consistency checks
level 3 = spatial consistency check
Subjective intervention:
G - Subjective good
B - Subjective bad
Interpolated/Corrected observations:
T - Virtual temperature could not be calculated, air temperature passing all QC
checks has been returned