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Cold and hot temperatures can impact cattle health and wellbeing while grazing rangelands. Commercial rumen boluses can now remotely provide an indication of body temperature as well as an index of water intake. Ten 2-year-old Corriente heifers were monito red using smaXtec classic rumen boluses during June-August 2023 and January-February 2024 in a 312-hectare rangeland pasture near Prescott, Arizona USA. Reticular temperature measurements with and without proprietary adjustments for drinking water as well as activity indices were recorded every 10 seconds and reported as 10-minute averages. For analyses, temperatures were averaged hourly, every 3 hours and every 24 hours. During both summer and winter water-intake adjusted reticular temperatures (ART) varied by 0.6 C, and it was highest during late evening (1800 to 2159 hours) and lowest in the morning (0900 to 1159 hours). During the summer, ART was more closely associated with wet bulb globe temperature (WBGT) than air temperature, thermal heat index (THI), relative humidity and weather measures on an hourly basis. On a 24-hour basis, ART increased as WBGT and THI increased during the summer. During the winter, ART was most closely related to ambient temperature (AT) on an hourly basis. On a 24-hour basis during the winter, ART decreased during windy days, and ART initially increased with higher relative humidity and then decreased when relative humidity was over 70%. Estimated daily water intake decreased during peri ods of higher relative humidity during both summer and winter. Rumen boluses appear to be a useful tool to remotely monitor and study cattle responses to hot and cold weather while grazing extensive rangeland pastures.