Irrigation is used in the Canadian Prairies to reduce the soil moisture deficit in crop production; however, prudent usage of water resources is required to ensure sustainability. Irrigation scheduling reduces water consumption by predicting when and how much irrigation is needed. Current irrigation scheduling techniques often estimate crop water consumption through evapotranspiration-based methods, which can be expensive and complex. Thermal remote sensing is an emerging alternative method that can indirectly predict when irrigation is needed through increasing canopy temperatures. The Water Deficit Index (WDI) is a thermal index that estimates relative evapotranspiration rates over partially vegetated surfaces. This research aims to increase the understanding of using WDI throughout the growing season to identify crop water stress, trigger irrigation scheduling and estimate the irrigation volume required to eliminate the soil moisture deficit. Remotely-sensed data was collected between June and September 2022 over an irrigated wheat field in Outlook, Saskatchewan, using ground-based monitoring stations and unpiloted ariel vehicle flights. In-situ soil water content measurements were compared to WDI, and crop water use was measured using evapotranspiration-based methods with an Eddy Covariance flux system. Successful implementation of this research will help farmers decrease costs associated with irrigation and improve the efficient use of water resources in the agricultural sector.