Infantry Drills

A-36: Analysis of Terrain and Weather

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A-36. When analyzing terrain, leaders consider manmade features and effects on natural terrain features and climate. Leaders also consider the effects of manmade and natural terrain in conjunction with the weather on friendly and enemy operations. In general, terrain and weather do not favor one side over the other unless one is better prepared to operate in the environment or is more familiar with it. The terrain, however, may favor defending or attacking. Analysis of terrain answers the question: What is the terrain’s effect on the operation? Leaders analyze terrain using the categories of OAKOC.

A-37. From the modified combined obstacle overlay (MCOO) developed by higher headquarters, leaders already appreciate the general nature of the ground and effects of weather. However, they must conduct their own detailed analyses to determine how terrain and weather uniquely affects their units’ missions and the enemy. They must go beyond merely passing along the MCOO to their subordinate leaders and making general observations of the terrain such as “This is high ground,” or “This is a stream.” They must determine how the terrain and weather will affect the enemy and their units. Additionally, they apply these conclusions when they develop COA for both enemy forces and their units. At company level and below, leaders develop a graphic terrain analysis overlay. This product is similar to the MCOO in it shows the critical military aspects of terrain. Not only does it facilitate planning, but it also aids in briefing subordinates.

Next: A-38: Defined Operational Environment

Go Back To: U.S. Army FM 3-21.8: The Infantry Rifle Platoon and Squad