Building Assessment Survey and Evaluation (BASE) Study
Ten Climate Regions of the BASE Target Cities
Building design and operation is influenced by climatic considerations, therefore various climatic regions were represented in the study. The BASE Regional Map is the ten BASE study climatic regions.
See the table below for descriptions of the letter designations for each climatic region

Ten Climate Regions of the BASE Target Cities
| Summer Design Conditions a | |||||
| Dew Point < 53 °F | Dew Point ≥ 53 °F | ||||
| Temp. < 94 °F (Cool/Mod.) |
Temp.≥ 94°F (Hot) |
Temp. < 94
°F (Cool/Mod.) |
Temp.≥ 94 °F (Hot) |
||
| Winter Design Temp. |
Cool ≤ 10 °F | Climate Region A |
Climate Region A |
Climate Region B |
Climate Region C |
| Mod. 11 °F - 32 °F | Climate Region D |
Climate Region E |
Climate Region D or I |
Climate Region F |
|
| Hot > 32 °F | Climate Region G |
Climate Region H |
Climate Region G or J |
Climate Region G or H |
|
°F = Degrees Fahrenheit
a = 2.5% dry-bulb design temperature
b = 97.5% dry-bulb design temperature
Reference: American Society of Heating, Refrigerating and Air Conditioning Engineers, Inc., Chapter 26, Table 1 Climatic Conditions for the United States, in: "1989 ASHRAE Handbook Fundamental."
Please forward all comments and questions concerning BASE and this map to the BASE Workgroup BASEworkgroup@epa.gov
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