PERMFILE133656

• Permit No: M1977300
• IBM Index Class Name: Permit File
• Doc Date: 9/30/1978
• Doc Name: REGULAR 112 PERMIT APPLICATION FORM
• Media Type: D
• Archive: No

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EXHIBIT K - Climate
In general terms, the climate at the mine site is characteristic
of semi-arid plains regions. Typical of mid-latitudes, the upper
level winds prevail from the west. However, the protective topo-
graphy of the Rocky Mountains greatly modifies the climate from
other characterisitcs which are common to the mid-latitudes.
During the winter season, low pressure systems causing abrupt
changes in the weather usually became disorganized at lower ele-
vations when crossing the mountains. Pacific maritime air (i.e. a
moist and cool air mass) loses most of its moisture when migrating
across the Cascades, Sierra Nevadas and Rockies. Under certain
conditions, (i.e. upslope air flow) moist air from the Gulf of
Mexico flows into the area and can cause significant precipitation.
• Large scale, high pressure systems often linger over the front range
for several days, especially during the winter season. The persistence
of these air mass conditions cause an abundance of clear skies, light
winds and sunny days with large daily temperature changes.
During the summer, the regional weather conditions are dominated
by a large area of relatively low pressure associated with the hot
continental effect. The days are warm, nights are cool, and wind speed
and direction highly variable. Precipitation is normally attributed to
localized thunderstorr:~ activity, which varies in spatial distribution
and frequency of occurance due to changes in locally available atmos-
pheric water vapor, surface heating and terrain. (see Table K-1).
K-1
•