The Thatcher Mountain Cooperative Wildlife Management Unit (CWMU) is located in Box Elder County about two miles northwest from Penrose, Utah. Thatcher Mountian is the prominent feature of the CWMU rising to 6240 feet. The south end of the Blue Spring Hills makes up the west third of the unit, ranging from 5200 feet to 6100 feet. The most common elevation is 5200 feet, but it ranges from 4400 feet to 6200 feet, a difference of 1800 feet. Fifty-two percent (52%) of the unit's elevation ranges between 5300 feet to 6200 feet, a difference of 900 feet. Inter-Mountain Basins Big Sagebrush Shrubland (48) is the dominant land cover. This land cover is very dominant on the westside of the unit. Great Basin Pinyon-Juniper Woodland (37) and Inter-Mountain Basins Semi-Desert Grassland (76) are other prominent land cover types. The pinyon-juniper cover is spread across the unit, and the grassland cover is mostly on the eastside of Thatcher Mountain. With Invasive Annual Grassland (121) and Agriculture (114), 92% of the unit is covered. . One of the Thatcher Mountain Cooperative Wildlife Management Unit (CWMU) nearest weather stations, THIOKOL PLANT 78 (428668), is about 5.1 km northwest from the northwest edge of the CWMU. THIOKOL PLANT 78 has forty-five (45) years of records, 1962 - 2007. During the FALL (September, October and November) the average percipitation is 3.59 inches, but it can be as high as 8.85 inches or as low as 0.50 inch. During the 91-day FALL period, 18 days will experience greater than or equal to 0.01 inch of percipitation, 9 days of greater than or equal to 0.10 inch, or 2 days of the greater than or equal to 0.50 inch of percipitation. Snowfall during the FALL averages 2.8 inches but can be as high as 18.8 inches. FALL temperature at THIOKOL PLANT 78 averages 48.0 degrees F. but can be as high as 98.0 degrees F. or as low as -17.0 degrees F. During the FALL, 47 days will be below freezing (32 degrees F.) and 3 days above 90 degrees F.