<Tr> <Th> Average relative humidity (%) </Th> <Td> 67.5 </Td> <Td> 66.4 </Td> <Td> 63.7 </Td> <Td> 65.3 </Td> <Td> 69.7 </Td> <Td> 65.8 </Td> <Td> 59.8 </Td> <Td> 59.5 </Td> <Td> 66.5 </Td> <Td> 65.7 </Td> <Td> 67.4 </Td> <Td> 67.5 </Td> <Td> 65.4 </Td> </Tr> <Tr> <Th> Mean monthly sunshine hours </Th> <Td> 183.5 </Td> <Td> 178.3 </Td> <Td> 227.7 </Td> <Td> 236.0 </Td> <Td> 258.4 </Td> <Td> 297.8 </Td> <Td> 332.4 </Td> <Td> 304.5 </Td> <Td> 246.2 </Td> <Td> 228.1 </Td> <Td> 183.8 </Td> <Td> 173.0 </Td> <Td> 2,849.7 </Td> </Tr> <Tr> <Th> Percent possible sunshine </Th> <Td> 58 </Td> <Td> 58 </Td> <Td> 61 </Td> <Td> 61 </Td> <Td> 60 </Td> <Td> 69 </Td> <Td> 76 </Td> <Td> 74 </Td> <Td> 66 </Td> <Td> 65 </Td> <Td> 59 </Td> <Td> 56 </Td> <Td> 64 </Td> </Tr> <Tr> <Td_colspan="14"> Source: NOAA (sun and relative humidity 1961--1990 at DFW Airport) </Td> </Tr>

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