2018 Mixing Height Average Std Dev By Local Daylight Time By Local Daylight Time and Season January 598.3 392.9 Hour Annual Std Dev Winter Avg Spring Avg Summer Avg Fall Avg February 651.4 488.6 1 465.6 191.7 518.4 470.9 393.7 480.7 March 806.7 639.9 2 489.2 304.4 550.4 530.9 394.6 482.2 April 870.5 785.8 3 470.5 237.8 525.2 493.6 398.3 466.0 May 1169.2 1274.3 4 478.3 246.1 537.5 524.4 391.3 461.1 June 1233.5 1499.5 5 470.2 231.4 526.2 516.9 389.6 449.0 July 1197.0 1342.8 6 451.7 232.4 489.5 509.3 370.5 438.1 August 1099.7 1283.1 7 445.5 271.1 460.1 488.6 376.5 457.9 September 1040.8 1285.8 8 443.6 254.8 434.3 505.0 408.9 426.8 October 721.4 665.4 9 479.7 244.3 455.6 570.6 444.2 448.4 November 607.6 341.3 10 695.1 568.3 499.9 825.6 936.0 512.9 December 566.3 304.7 11 1152.0 1049.3 582.9 1192.1 1920.2 898.0 12 1406.2 1148.0 642.5 1536.2 2187.8 1239.7 Annual 881.3 13 1663.4 1277.8 815.8 1774.5 2596.8 1445.7 Max 7902.7 14 1778.1 1303.9 864.0 1897.2 2724.1 1605.1 Min 180.0 15 1886.5 1328.3 946.5 2031.9 2888.8 1656.1 Std Dev 991.1 16 1902.8 1363.3 1030.5 2078.7 2783.5 1697.5 17 1951.4 1472.5 1021.9 2065.2 3053.3 1641.8 18 1560.7 1495.6 664.7 1742.2 2698.1 1113.3 19 681.1 818.6 486.7 688.6 975.6 567.8 20 440.4 277.4 476.5 405.6 370.2 510.7 21 454.0 243.7 481.3 454.7 376.3 504.9 22 455.1 242.5 481.9 491.5 375.9 471.9 23 463.3 284.6 499.4 490.2 376.5 488.3 24 462.7 198.6 499.4 488.6 387.2 476.5 2018 Synoptic Pressure Gradient ORNL-NAM Boundary Layer Wind (kts) ORNL-NAM Boundary Layer Wind (kts) Average Std Dev 850-mb Average Std Dev 925-mb Average Std Dev January 0.013 0.008 January 20.9 10.0 January 16.3 8.3 February 0.012 0.006 February 28.3 12.8 February 21.4 10.7 March 0.011 0.006 March 23.6 10.7 March 16.9 8.3 April 0.011 0.006 April 22.6 12.3 April 16.5 9.2 May 0.006 0.003 May 14.4 8.1 May 13.0 7.2 June 0.005 0.003 June 12.8 7.6 June 11.1 6.7 July 0.005 0.002 July 8.8 5.1 July 8.6 4.7 August 0.004 0.003 August 10.7 6.5 August 9.1 5.7 September 0.006 0.004 September 13.7 8.8 September 11.5 7.3 October 0.009 0.005 October 16.9 10.0 October 12.0 7.3 November 0.011 0.006 November 20.9 12.9 November 14.3 8.8 December 0.011 0.006 December 22.1 12.0 December 15.2 8.3 Annual 0.009 0.006 Annual 17.9 11.5 Annual 13.8 8.6