Soaring Guidance
Issued by NWS Denver/Boulder, CO

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211
UXUS97 KBOU 110141
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1940 MDT Thursday, April 10, 2025

This forecast is for Friday, April 11, 2025:

If the trigger temperature of 69.3 F/20.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1251 ft/min (6.4 m/s)
   Maximum height of thermals.................. 18828 ft MSL (13535 ft AGL)

Forecast maximum temperature................... 80.0 F/27.1 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12296 ft MSL (7002 ft AGL)
Thermal soaring outlook for Saturday 04/12..... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 45870 ft MSL (40577 ft AGL)
Wave soaring outlook for Saturday 04/12........ Poor

Remarks...

Sunrise/Sunset.................... 06:26:57 / 19:33:47 MDT
Total possible sunshine........... 13 hr 6 min 50 sec (786 min 50 sec)
Altitude of sun at 13:00:22 MDT... 58.85 degrees

Upper air data from numerical model forecast valid on 04/11/2025 at 0600 MDT

Freezing level.................. 13244 ft MSL (7951 ft AGL)
Convective condensation level... 19816 ft MSL (14523 ft AGL)
Lifted condensation level....... 19793 ft MSL (14500 ft AGL)
Lifted index.................... -0.1
K index......................... -17.9

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -63.3 -81.9   305   54   28   2.9   1.6      M     M       M      M    M
 45000  -59.3 -74.7   305   61   31  -0.1  -0.1      M     M       M      M    M
 40000  -59.5 -75.1   310   45   23  -0.6  -0.3      M     M       M      M    M
 38000  -56.6 -69.9   310   42   21   5.8   3.2      M     M       M      M    M
 36000  -53.2 -63.8   310   38   20   5.8   3.2      M     M       M      M    M
 34000  -49.7 -57.5   305   35   18   5.7   3.1      M     M       M      M    M
 32000  -46.3 -51.3   305   34   17   5.7   3.1      M     M       M      M    M
 30000  -41.5 -42.7   305   31   16   8.3   4.6   33.3  92.0     5.0      M    M
 29000  -39.1 -38.4   305   30   15   8.3   4.6   32.7  90.9     4.6      M    M
 28000  -36.6 -33.9   305   28   14   8.3   4.6   32.3  90.1     4.3      M    M
 27000  -34.1 -29.4   305   27   14   8.2   4.5   31.7  89.0     3.9      M    M
 26000  -31.7 -25.1   305   26   13   8.2   4.5   31.1  87.9     3.4      M    M
 25000  -29.2 -20.6   305   25   13   8.2   4.5   30.6  87.0     3.0      M    M
 24000  -26.7 -16.1   300   25   13   8.2   4.5   30.0  86.0     2.6      M    M
 23000  -24.2 -11.6   300   25   13   8.2   4.5   29.4  84.9     2.2      M    M
 22000  -21.8  -7.2   300   24   12   8.3   4.5   28.9  84.1     1.8      M    M
 21000  -19.4  -2.9   300   24   12   7.7   4.2   28.2  82.8     1.3      M    M
 20000  -17.1   1.2   300   23   12   7.7   4.2   27.5  81.5     0.7      M    M
 19500  -15.9   3.4   300   22   11   7.7   4.2   27.2  80.9     0.4      M    M
 19000  -14.7   5.5   300   22   11   7.8   4.3   26.9  80.4     0.2      M    M
 18500  -13.6   7.5   300   22   11   7.8   4.3   26.5  79.8    -0.2   1225  6.2
 18000  -12.4   9.7   300   21   11   7.8   4.3   26.2  79.2    -0.4   1176  6.0
 17500  -11.2  11.8   300   21   11   8.3   4.5   25.9  78.6    -0.7   1125  5.7
 17000  -10.0  14.0   300   21   11   8.2   4.5   25.6  78.2    -0.9   1073  5.5
 16500   -8.7  16.3   300   21   11   8.4   4.6   25.4  77.7    -1.2   1021  5.2
 16000   -7.5  18.5   300   21   11   8.4   4.6   25.2  77.3    -1.4    968  4.9
 15500   -6.2  20.8   300   20   10   8.5   4.7   25.0  76.9    -1.6    916  4.7
 15000   -4.2  24.4   300   20   10   8.7   4.8   24.7  76.4    -1.8    835  4.2
 14500   -2.9  26.8   300   20   10   8.5   4.7   24.5  76.1    -2.0    781  4.0
 14000   -1.7  28.9   305   19   10   8.5   4.6   24.3  75.7    -2.2    728  3.7
 13500   -0.4  31.3   305   18    9   8.3   4.6   24.1  75.4    -2.4    676  3.4
 13000    0.8  33.4   305   18    9   8.2   4.5   23.8  74.9    -2.7    624  3.2
 12500    2.0  35.6   305   17    9   8.0   4.4   23.6  74.5    -2.9    573  2.9
 12000    3.2  37.8   305   16    8   7.7   4.2   23.3  73.9    -3.2    523  2.7
 11500    4.3  39.7   300   15    8   7.6   4.2   23.0  73.3    -3.6    474  2.4
 11000    5.4  41.7   300   13    7   7.3   4.0   22.6  72.6    -4.0    427  2.2
 10500    6.5  43.7   300   12    6   6.0   3.3   22.2  72.0    -4.4    379  1.9
 10250    6.8  44.2   300   11    6   4.1   2.3   21.8  71.2    -4.8    362  1.8
 10000    7.2  45.0   300   11    5   6.9   3.8   21.4  70.6    -5.1    343  1.7
  9750    7.8  46.0   295    9    5   9.1   5.0   21.3  70.4    -5.3    318  1.6
  9500    8.4  47.1   295    7    4   6.6   3.6   21.2  70.2    -5.4    292  1.5
  9250    8.8  47.8   290    7    3   4.1   2.2   20.8  69.5    -5.8    274  1.4
  9000    9.1  48.4   290    6    3   6.1   3.4   20.5  68.8    -6.2    256  1.3
  8750    9.7  49.5   285    5    2   8.3   4.5   20.3  68.5    -6.4    233  1.2
  8500   10.2  50.4   275    4    2   6.2   3.4   20.1  68.2    -6.6    210  1.1
  8250   10.5  50.9   265    3    2   4.3   2.3   19.7  67.5    -7.0    192  1.0
  8000   10.9  51.6   255    3    2   5.4   3.0   19.3  66.8    -7.5    174  0.9
  7750   11.3  52.3   245    3    1   6.0   3.3   19.1  66.3    -7.8    155  0.8
  7500   11.7  53.1   240    3    2   4.4   2.4   18.7  65.7    -8.2    136  0.7
  7250   11.9  53.4   235    3    2   3.2   1.7   18.2  64.8    -8.7    122  0.6
  7000   12.2  54.0   235    3    2   4.3   2.4   17.8  64.0    -9.2    107  0.5
  6750   12.4  54.3   235    4    2   2.2   1.2   17.3  63.2    -9.7     91  0.5
  6500   12.4  54.3   230    4    2  -0.8  -0.4   16.6  61.9   -10.4     84  0.4
  6250   12.4  54.3   230    4    2   1.6   0.9   15.9  60.5   -11.2     77  0.4
  6000   12.4  54.3   225    4    2  -5.1  -2.8   15.1  59.2   -12.0     70  0.4
  5750   11.3  52.3   225    4    2 -24.3 -13.3   13.3  56.0   -13.8     96  0.5
  5500    8.8  47.8   220    4    2 -36.1 -19.8   10.2  50.3   -17.1    162  0.8

 * * * * * * Numerical weather prediction model forecast data valid * * * * * *

           04/11/2025 at 0900 MDT          |       04/11/2025 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +3.7        | CAPE...     0.0    LI...       +4.4
CINH...    -1.5    K Index... -15.8        | CINH...    -1.0    K Index...  -8.1
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.5 -82.3  305  55 28   2.8   1.6 | -63.5 -82.3  300  54 28   2.9   1.6
 45000 -59.5 -75.1  305  57 29   0.7   0.4 | -59.4 -74.9  300  55 28   0.9   0.5
 40000 -58.5 -73.3  305  38 20   0.3   0.2 | -58.1 -72.6  295  38 19   0.6   0.3
 38000 -55.9 -68.6  305  36 18   5.1   2.8 | -55.7 -68.3  295  34 17   4.6   2.5
 36000 -52.8 -63.0  305  34 18   5.1   2.8 | -52.9 -63.2  300  31 16   4.6   2.5
 34000 -49.4 -56.9  310  32 16   6.4   3.5 | -49.8 -57.6  310  28 14   6.0   3.3
 32000 -45.6 -50.1  315  29 15   6.4   3.5 | -45.7 -50.3  325  27 14   6.0   3.3
 30000 -41.1 -42.0  315  27 14   6.9   3.8 | -41.3 -42.3  325  27 14   8.1   4.5
 29000 -39.0 -38.2  315  27 14   7.0   3.8 | -38.9 -38.0  325  27 14   8.1   4.5
 28000 -36.9 -34.4  310  26 13   6.8   3.7 | -36.5 -33.7  325  27 14   8.1   4.5
 27000 -34.5 -30.1  310  26 13   8.7   4.8 | -34.0 -29.2  320  27 14   8.4   4.6
 26000 -31.9 -25.4  310  25 13   8.7   4.8 | -31.5 -24.7  320  26 13   8.4   4.6
 25000 -29.3 -20.7  310  25 13   8.7   4.8 | -28.9 -20.0  320  25 13   8.4   4.6
 24000 -26.7 -16.1  305  25 13   8.7   4.8 | -26.4 -15.5  315  24 12   8.7   4.8
 23000 -24.1 -11.4  305  24 12   8.7   4.8 | -23.8 -10.8  315  24 12   8.7   4.8
 22000 -21.5  -6.7  300  24 12   8.8   4.8 | -21.2  -6.2  315  23 12   8.8   4.8
 21000 -19.0  -2.2  300  23 12   7.8   4.3 | -18.6  -1.5  310  22 11   8.4   4.6
 20000 -16.7   1.9  300  21 11   7.8   4.3 | -16.1   3.0  310  21 11   8.4   4.6
 19500 -15.5   4.1  300  21 11   7.8   4.3 | -14.8   5.4  305  21 11   8.4   4.6
 19000 -14.3   6.3  300  20 10   7.6   4.2 | -13.5   7.7  305  20 10   7.9   4.3
 18500 -13.2   8.2  300  20 10   7.5   4.1 | -12.4   9.7  305  20 10   7.5   4.1
 18000 -12.1  10.2  300  19 10   7.5   4.1 | -11.3  11.7  300  19 10   7.5   4.1
 17500 -11.0  12.2  300  18 10   7.6   4.1 | -10.2  13.6  300  18  9   6.7   3.7
 17000  -9.8  14.4  300  18  9   7.5   4.1 |  -8.7  16.3  295  16  8   6.8   3.7
 16500  -8.1  17.4  305  17  9   8.0   4.4 |  -7.7  18.1  295  16  8   7.0   3.9
 16000  -6.9  19.6  305  17  9   7.9   4.3 |  -6.6  20.1  295  15  8   7.0   3.8
 15500  -5.7  21.7  305  16  8   8.2   4.5 |  -5.6  21.9  295  14  7   7.7   4.2
 15000  -4.5  23.9  310  16  8   8.2   4.5 |  -4.4  24.1  295  13  7   7.7   4.2
 14500  -3.2  26.2  310  15  8   8.5   4.7 |  -3.3  26.1  295  13  7   8.4   4.6
 14000  -1.9  28.6  310  15  8   8.6   4.7 |  -2.0  28.4  295  13  7   8.6   4.7
 13500  -0.6  30.9  310  14  7   8.6   4.7 |  -0.7  30.7  295  13  6   8.7   4.8
 13000   0.6  33.1  310  13  7   8.6   4.7 |   0.6  33.1  295  12  6   8.8   4.8
 12500   1.9  35.4  310  12  6   8.5   4.7 |   1.9  35.4  295  11  6   8.8   4.8
 12000   3.2  37.8  310  11  6   8.3   4.6 |   3.2  37.8  295  11  6   8.9   4.9
 11500   4.4  39.9  310  10  5   8.2   4.5 |   4.6  40.3  295  10  5   8.8   4.9
 11000   5.6  42.1  305   9  5   7.8   4.3 |   5.9  42.6  290   9  5   8.6   4.7
 10500   6.8  44.2  305   8  4   6.1   3.4 |   7.2  45.0  290   8  4   5.9   3.2
 10250   7.1  44.8  300   7  4   4.4   2.4 |   7.5  45.5  285   8  4   4.8   2.6
 10000   7.6  45.7  295   7  3   7.9   4.3 |   8.1  46.6  285   7  4  10.2   5.6
  9750   8.3  46.9  295   6  3  10.4   5.7 |   9.0  48.2  280   7  3  12.3   6.7
  9500   9.0  48.2  285   5  3   7.4   4.1 |   9.8  49.6  275   6  3   9.0   5.0
  9250   9.4  48.9  280   5  2   4.2   2.3 |  10.3  50.5  270   5  3   4.9   2.7
  9000   9.7  49.5  270   4  2   6.7   3.7 |  10.8  51.4  265   5  3   8.0   4.4
  8750  10.3  50.5  255   4  2   9.0   4.9 |  11.5  52.7  250   5  2  10.7   5.9
  8500  10.9  51.6  240   4  2   6.7   3.7 |  12.2  54.0  235   4  2   7.8   4.3
  8250  11.3  52.3  230   4  2   4.7   2.6 |  12.7  54.9  225   4  2   5.4   3.0
  8000  11.7  53.1  225   4  2   6.3   3.5 |  13.1  55.6  210   4  2   7.8   4.3
  7750  12.2  54.0  215   5  2   7.3   4.0 |  13.8  56.8  200   5  2  10.3   5.6
  7500  12.7  54.9  210   5  3   5.1   2.8 |  14.5  58.1  195   5  3   8.7   4.8
  7250  12.9  55.2  210   5  3   2.9   1.6 |  15.1  59.2  190   5  3   6.7   3.7
  7000  13.2  55.8  210   6  3   6.1   3.4 |  15.6  60.1  190   5  3   9.3   5.1
  6750  13.7  56.7  210   6  3   3.8   2.1 |  16.4  61.5  185   5  3  12.2   6.7
  6500  13.6  56.5  210   6  3  -1.0  -0.6 |  17.3  63.1  180   5  3  10.9   6.0
  6250  13.6  56.5  210   6  3   1.6   0.9 |  18.1  64.6  180   5  3  10.6   5.8
  6000  13.6  56.5  210   6  3  -4.1  -2.3 |  18.8  65.8  180   5  2   8.9   4.9
  5750  13.1  55.6  210   6  3  -4.5  -2.5 |  19.6  67.3  180   5  2  13.8   7.6
  5500  13.3  55.9  205   5  3  10.6   5.8 |  21.1  70.0  180   4  2  27.4  15.0

           04/11/2025 at 1500 MDT          |       04/11/2025 at 1800 MDT
                                           |
CAPE...     0.0    LI...       +3.6        | CAPE...     0.0    LI...       +2.4
CINH...    -0.3    K Index...  +2.2        | CINH...    -0.1    K Index... +10.3
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.0 -81.4  300  51 26   2.9   1.6 | -62.8 -81.0  295  49 25   3.3   1.8
 45000 -58.8 -73.8  295  53 27   0.8   0.4 | -58.3 -72.9  290  53 27  -0.0  -0.0
 40000 -57.7 -71.9  290  40 20   0.6   0.3 | -58.3 -72.9  295  45 23  -0.2  -0.1
 38000 -55.9 -68.6  295  36 18   3.3   1.8 | -56.8 -70.2  305  40 21   3.0   1.7
 36000 -54.0 -65.2  305  33 17   3.3   1.8 | -55.0 -67.0  310  37 19   3.1   1.7
 34000 -50.9 -59.6  310  31 16   7.0   3.9 | -51.7 -61.1  320  34 18   8.5   4.6
 32000 -46.7 -52.1  315  29 15   7.0   3.9 | -45.9 -50.6  320  32 16   8.5   4.6
 30000 -41.3 -42.3  315  29 15   8.9   4.9 | -40.7 -41.3  315  30 16   8.9   4.9
 29000 -38.7 -37.7  320  30 15   8.9   4.9 | -38.0 -36.4  315  30 15   8.9   4.9
 28000 -36.0 -32.8  320  30 15   8.9   4.9 | -35.3 -31.5  310  30 15   9.0   4.9
 27000 -33.4 -28.1  315  29 15   8.6   4.7 | -32.7 -26.9  310  29 15   8.7   4.8
 26000 -30.8 -23.4  310  28 14   8.6   4.7 | -30.1 -22.2  305  29 15   8.7   4.8
 25000 -28.3 -18.9  305  27 14   8.6   4.7 | -27.5 -17.5  305  29 15   8.7   4.8
 24000 -25.7 -14.3  305  25 13   8.5   4.7 | -25.1 -13.2  300  28 14   8.0   4.4
 23000 -23.2  -9.8  305  24 12   8.5   4.7 | -22.7  -8.9  305  26 13   8.0   4.4
 22000 -20.6  -5.1  305  23 12   8.5   4.7 | -20.3  -4.5  305  24 13   8.0   4.4
 21000 -18.0  -0.4  305  21 11   8.8   4.8 | -17.8  -0.0  300  22 12   8.5   4.7
 20000 -15.3   4.5  305  20 10   8.8   4.8 | -15.2   4.6  290  21 11   8.5   4.7
 19500 -14.0   6.8  305  19 10   8.8   4.8 | -14.0   6.8  285  20 10   8.5   4.7
 19000 -12.7   9.1  305  18  9   8.3   4.5 | -12.7   9.1  285  19 10   8.1   4.4
 18500 -11.5  11.3  305  18  9   7.9   4.3 | -11.5  11.3  280  19 10   7.8   4.3
 18000 -10.3  13.5  300  17  9   7.9   4.3 | -10.4  13.3  275  18  9   7.7   4.2
 17500  -9.2  15.4  295  18  9   7.2   4.0 |  -9.2  15.4  270  18  9   8.0   4.4
 17000  -8.1  17.4  295  18  9   7.3   4.0 |  -8.1  17.4  270  18  9   8.0   4.4
 16500  -7.0  19.4  290  19 10   7.3   4.0 |  -6.9  19.6  270  18  9   8.0   4.4
 16000  -5.9  21.4  285  19 10   7.3   4.0 |  -5.7  21.7  270  17  9   8.0   4.4
 15500  -4.8  23.4  280  19 10   7.5   4.1 |  -3.9  25.0  265  16  8   8.7   4.8
 15000  -3.1  26.4  280  19 10   7.8   4.3 |  -2.6  27.3  270  15  8   8.8   4.8
 14500  -2.0  28.4  280  19 10   8.0   4.4 |  -1.3  29.7  270  15  8   8.9   4.9
 14000  -0.8  30.6  280  17  9   8.1   4.5 |   0.0  32.0  270  14  7   9.0   5.0
 13500   0.4  32.7  280  16  8   8.5   4.7 |   1.4  34.5  270  13  6   9.0   4.9
 13000   1.7  35.1  275  14  7   8.9   4.9 |   2.7  36.9  270  11  6   8.9   4.9
 12500   3.0  37.4  275  13  7   9.1   5.0 |   4.0  39.2  270  10  5   9.0   4.9
 12000   4.4  39.9  275  11  6   9.3   5.1 |   5.4  41.7  270   9  5   9.3   5.1
 11500   5.8  42.4  270  10  5   9.3   5.1 |   6.8  44.2  270   8  4   9.2   5.1
 11000   7.2  45.0  270   8  4   9.0   5.0 |   8.1  46.6  265   7  4   8.7   4.8
 10500   8.6  47.5  270   7  4   5.0   2.8 |   9.5  49.1  265   6  3   5.4   3.0
 10250   8.8  47.8  265   7  3   4.3   2.4 |   9.7  49.5  265   6  3   5.4   3.0
 10000   9.4  48.9  265   6  3  11.4   6.3 |  10.5  50.9  260   5  3  11.2   6.1
  9750  10.3  50.5  260   5  3  12.7   7.0 |  11.3  52.3  255   5  2  11.4   6.3
  9500  11.2  52.2  255   4  2   9.5   5.2 |  12.1  53.8  250   4  2   9.8   5.4
  9250  11.8  53.2  250   4  2   5.1   2.8 |  12.7  54.9  245   4  2   6.4   3.5
  9000  12.2  54.0  245   4  2   9.0   4.9 |  13.2  55.8  240   4  2   8.8   4.8
  8750  13.1  55.6  235   3  2  13.0   7.1 |  14.1  57.4  235   3  2  11.9   6.6
  8500  14.0  57.2  225   3  2   9.5   5.2 |  14.9  58.8  225   3  2   9.3   5.1
  8250  14.6  58.3  220   3  2   6.2   3.4 |  15.4  59.7  220   3  2   6.0   3.3
  8000  15.1  59.2  215   3  2   9.4   5.2 |  15.9  60.6  215   3  2   8.2   4.5
  7750  16.0  60.8  210   3  2  12.9   7.1 |  16.7  62.1  210   3  1  12.3   6.8
  7500  16.9  62.4  205   3  2  10.3   5.6 |  17.6  63.7  205   3  1  10.1   5.5
  7250  17.5  63.5  200   3  2   7.6   4.2 |  18.2  64.8  205   3  1   7.4   4.0
  7000  18.1  64.6  200   3  1   9.9   5.4 |  18.8  65.8  205   3  1   9.0   4.9
  6750  19.0  66.2  195   3  1  12.7   7.0 |  19.6  67.3  200   3  1  11.8   6.4
  6500  19.9  67.8  190   3  1  11.0   6.0 |  20.5  68.9  195   3  1  10.6   5.8
  6250  20.7  69.3  185   3  1  10.2   5.6 |  21.1  70.0  195   2  1   8.2   4.5
  6000  21.4  70.5  185   3  1   8.0   4.4 |  21.8  71.2  195   2  1   9.7   5.3
  5750  22.0  71.6  180   3  1  11.7   6.4 |  22.6  72.7  190   2  1  11.3   6.2
  5500  23.4  74.1  175   3  1  26.1  14.3 |  23.4  74.1  190   2  1  11.0   6.0
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CINH (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613