  The paper contains a description of the KMS weights for the one-parameter
action on the reduced C*-algebra of a second countable locally compact
Hausdorff etale groupoid, arising from a continuous real valued homomorphism
satisfying two conditions. The results are subsequently applied to identify the
KMS weights for the gauge action on a simple graph algebra. The von Neumann
algebra generated by the GNS-representation of an extremal KMS weight is a
factor, and tools are developed to determine its type. The paper concludes with
three examples to illustrate the results.
