Soaring Guidance
Issued by NWS Denver/Boulder, CO

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505
UXUS97 KBOU 181255
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0651 MDT Monday, August 18, 2025

This forecast is for Monday, August 18, 2025:

If the trigger temperature of 85.6 F/29.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1373 ft/min (7.0 m/s)
   Maximum height of thermals.................. 17654 ft MSL (12354 ft AGL)

Forecast maximum temperature................... 92.0 F/33.8 C
Time of trigger temperature.................... 1130 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................. 10319 ft MSL (5020 ft AGL)
Thermal soaring outlook for Tuesday 08/19...... 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 PVA
Potential height of wave....................... 31182 ft MSL (25882 ft AGL)
Wave soaring outlook for Tuesday 08/19......... Poor

Remarks...

Sunrise/Sunset.................... 06:15:00 / 19:51:26 MDT
Total possible sunshine........... 13 hr 36 min 26 sec (816 min 26 sec)
Altitude of sun at 13:03:13 MDT... 63.05 degrees

Upper air data from numerical model forecast valid on 08/18/2025 at 0600 MDT

Freezing level.................. 16241 ft MSL (10941 ft AGL)
Convective condensation level... 15713 ft MSL (10413 ft AGL)
Lifted condensation level....... 16109 ft MSL (10810 ft AGL)
Lifted index.................... -5.0
K index......................... +29.6

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  -63.5 -82.3   250   17    9   1.5   0.8      M     M       M      M    M
 45000  -58.7 -73.7   260   27   14   6.3   3.4      M     M       M      M    M
 40000  -49.3 -56.7   255   30   16   6.2   3.4      M     M       M      M    M
 38000  -45.6 -50.1   255   30   16   6.2   3.4      M     M       M      M    M
 36000  -41.9 -43.4   250   31   16   6.2   3.4      M     M       M      M    M
 34000  -37.6 -35.7   250   32   16   6.4   3.5      M     M       M      M    M
 32000  -33.7 -28.7   250   32   17   6.5   3.6      M     M       M      M    M
 30000  -29.5 -21.1   245   29   15   7.1   3.9   46.3 115.4     9.9      M    M
 29000  -27.3 -17.1   240   28   14   7.1   3.9   45.4 113.7     9.3      M    M
 28000  -25.3 -13.5   240   26   13   6.0   3.3   44.4 111.9     8.6      M    M
 27000  -23.5 -10.3   235   24   12   5.9   3.3   42.8 109.0     7.5      M    M
 26000  -21.7  -7.1   230   21   11   6.0   3.3   41.4 106.5     6.4      M    M
 25000  -19.9  -3.8   225   19   10   6.2   3.4   40.1 104.1     5.4      M    M
 24000  -18.0  -0.4   230   19   10   6.7   3.7   38.8 101.9     4.5      M    M
 23000  -16.0   3.2   230   19   10   6.8   3.7   37.7  99.9     3.6      M    M
 22000  -14.0   6.8   235   19   10   7.3   4.0   36.8  98.2     2.8      M    M
 21000  -11.7  10.9   235   19   10   7.9   4.3   36.0  96.8     2.1      M    M
 20000   -9.4  15.1   235   19   10   8.0   4.4   35.4  95.7     1.5      M    M
 19500   -8.2  17.2   235   20   10   8.1   4.4   35.1  95.2     1.2      M    M
 19000   -7.1  19.2   235   19   10   7.9   4.3   34.8  94.7     0.9      M    M
 18500   -6.0  21.2   235   18    9   8.0   4.4   34.5  94.1     0.5      M    M
 18000   -4.8  23.4   235   16    8   8.4   4.6   34.2  93.6     0.2      M    M
 17500   -2.9  26.8   230   15    8   8.6   4.7   33.9  93.1    -0.1   1143  5.8
 17000   -1.7  28.9   225   14    7   8.8   4.8   33.8  92.8    -0.3   1090  5.5
 16500   -0.4  31.3   225   13    7   8.9   4.9   33.6  92.5    -0.5   1037  5.3
 16000    0.9  33.6   220   13    7   8.9   4.9   33.4  92.2    -0.7    984  5.0
 15500    2.2  36.0   220   13    6   9.0   4.9   33.3  92.0    -0.8    930  4.7
 15000    3.5  38.3   220   13    6   9.1   5.0   33.2  91.7    -1.0    877  4.5
 14500    4.7  40.5   220   13    7   8.4   4.6   33.0  91.4    -1.2    824  4.2
 14000    6.0  42.8   220   13    7   8.4   4.6   32.8  91.1    -1.5    772  3.9
 13500    7.2  45.0   215   14    7   8.7   4.8   32.6  90.7    -1.7    720  3.7
 13000    8.5  47.3   215   14    7   8.8   4.8   32.5  90.4    -1.9    666  3.4
 12500    9.8  49.6   210   14    7   9.2   5.0   32.3  90.2    -2.0    612  3.1
 12000   11.2  52.2   210   14    7   9.4   5.2   32.3  90.1    -2.1    556  2.8
 11500   12.6  54.7   210   14    7   8.9   4.9   32.2  90.0    -2.2    499  2.5
 11000   13.8  56.8   205   14    7   8.0   4.4   32.0  89.6    -2.4    447  2.3
 10500   15.1  59.2   205   13    7   4.1   2.2   31.8  89.2    -2.6    396  2.0
 10250   15.2  59.4   205   13    7   5.2   2.9   31.2  88.1    -3.2    384  1.9
 10000   16.0  60.8   205   12    6  11.1   6.1   31.2  88.1    -3.2    354  1.8
  9750   16.7  62.1   200   12    6  10.1   5.6   31.2  88.1    -3.2    325  1.6
  9500   17.4  63.3   200   11    6   8.2   4.5   31.2  88.2    -3.2    295  1.5
  9250   17.9  64.2   200   10    5   5.6   3.1   30.9  87.7    -3.5    274  1.4
  9000   18.3  64.9   200    9    5   7.1   3.9   30.7  87.2    -3.8    253  1.3
  8750   18.9  66.0   200    8    4   8.2   4.5   30.5  86.9    -4.0    229  1.2
  8500   19.4  66.9   200    7    3   6.1   3.3   30.4  86.6    -4.2    206  1.0
  8250   19.7  67.5   205    5    3   4.3   2.4   30.0  85.9    -4.6    189  1.0
  8000   20.0  68.0   210    4    2   4.4   2.4   29.6  85.2    -5.0    172  0.9
  7750   20.3  68.5   220    3    1   3.5   1.9   29.1  84.4    -5.5    157  0.8
  7500   20.5  68.9   250    2    1   2.1   1.1   28.6  83.5    -6.0    143  0.7
  7250   20.6  69.1   295    2    1   0.9   0.5   27.9  82.3    -6.7    133  0.7
  7000   20.7  69.3   320    3    1   1.9   1.0   27.3  81.1    -7.4    123  0.6
  6750   20.8  69.4   330    4    2  -1.4  -0.7   26.6  79.9    -8.0    114  0.6
  6500   20.4  68.7   330    4    2  -6.9  -3.8   25.5  78.0    -9.1    117  0.6
  6250   19.8  67.6   330    4    2  -8.8  -4.8   24.2  75.5   -10.5    129  0.7
  6000   19.1  66.4   325    4    2  -5.8  -3.2   22.9  73.1   -11.9    140  0.7
  5750   18.9  66.0   320    4    2  -1.0  -0.6   21.9  71.4   -13.0    141  0.7
  5500   18.8  65.8   280    2    1  -0.8  -0.4   21.1  70.0   -13.8    136  0.7

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

           08/18/2025 at 0900 MDT          |       08/18/2025 at 1200 MDT
                                           |
CAPE...  +123.3    LI...       -1.7        | CAPE...  +442.3    LI...       -2.9
CINH...  -347.8    K Index... +28.7        | CINH...   -87.1    K Index... +27.2
                                           |
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 -64.1 -83.4  250  16  8   1.6   0.9 | -64.3 -83.7  245  15  8   1.1   0.6
 45000 -58.8 -73.8  255  24 12   6.8   3.7 | -59.7 -75.5  260  27 14   6.5   3.6
 40000 -48.8 -55.8  260  28 14   6.2   3.4 | -49.6 -57.3  275  35 18   7.4   4.1
 38000 -45.1 -49.2  265  27 14   6.2   3.4 | -45.2 -49.4  270  30 16   7.4   4.1
 36000 -41.4 -42.5  265  26 13   6.2   3.4 | -40.7 -41.3  265  26 13   7.4   4.0
 34000 -37.0 -34.6  260  28 14   6.5   3.6 | -36.0 -32.8  260  28 14   7.0   3.8
 32000 -33.1 -27.6  260  30 16   6.4   3.5 | -31.8 -25.2  260  30 15   6.6   3.6
 30000 -29.6 -21.3  255  28 14   5.8   3.2 | -28.6 -19.5  255  28 15   5.2   2.9
 29000 -27.9 -18.2  250  27 14   5.8   3.2 | -27.0 -16.6  250  28 14   5.2   2.9
 28000 -26.1 -15.0  245  25 13   5.8   3.2 | -25.4 -13.7  250  27 14   5.3   2.9
 27000 -24.4 -11.9  240  23 12   5.9   3.2 | -23.8 -10.8  245  24 13   5.3   2.9
 26000 -22.6  -8.7  235  21 11   5.9   3.3 | -22.2  -8.0  240  22 11   5.3   2.9
 25000 -20.9  -5.6  225  20 10   6.4   3.5 | -20.7  -5.3  235  20 10   5.9   3.3
 24000 -18.8  -1.8  220  20 10   7.1   3.9 | -18.7  -1.7  235  19 10   6.8   3.7
 23000 -16.8   1.8  215  20 11   7.2   4.0 | -16.6   2.1  235  19 10   6.9   3.8
 22000 -14.7   5.5  210  21 11   8.3   4.5 | -14.6   5.7  235  18  9   7.7   4.2
 21000 -12.1  10.2  210  19 10   8.9   4.9 | -12.3   9.9  235  17  9   8.1   4.4
 20000  -9.5  14.9  210  16  8   8.9   4.9 |  -9.9  14.2  235  15  8   8.2   4.5
 19500  -8.2  17.2  215  15  8   8.7   4.8 |  -8.7  16.3  235  15  8   8.3   4.5
 19000  -7.1  19.2  215  14  7   6.8   3.7 |  -7.5  18.5  235  14  7   8.6   4.7
 18500  -6.1  21.0  210  13  7   6.9   3.8 |  -6.2  20.8  235  13  7   8.6   4.7
 18000  -5.0  23.0  210  13  7   8.4   4.6 |  -5.0  23.0  235  12  6   9.2   5.1
 17500  -3.0  26.6  210  12  6   9.0   4.9 |  -2.8  27.0  230  12  6   9.5   5.2
 17000  -1.6  29.1  210  12  6   9.5   5.2 |  -1.4  29.5  225  11  6   9.1   5.0
 16500  -0.2  31.6  210  11  6   9.7   5.3 |  -0.1  31.8  220  11  6   9.0   5.0
 16000   1.2  34.2  205  11  5   9.5   5.2 |   1.2  34.2  215  11  6   9.1   5.0
 15500   2.6  36.7  205  10  5   8.9   4.9 |   2.5  36.5  210  11  6   9.2   5.0
 15000   3.9  39.0  205  10  5   9.0   4.9 |   3.9  39.0  205  11  6   9.2   5.0
 14500   5.1  41.2  205   9  5   8.5   4.6 |   5.1  41.2  200  11  6   8.4   4.6
 14000   6.4  43.5  205   9  5   8.5   4.7 |   6.3  43.3  200  11  6   8.5   4.7
 13500   7.6  45.7  205   9  5   8.6   4.7 |   7.5  45.5  195  12  6   8.4   4.6
 13000   8.9  48.0  200   9  5   8.6   4.7 |   8.8  47.8  195  12  6   8.4   4.6
 12500  10.1  50.2  200   9  5   8.6   4.7 |  10.0  50.0  195  11  6   8.5   4.6
 12000  11.4  52.5  195   9  5   8.6   4.7 |  11.2  52.2  195  11  6   8.5   4.7
 11500  12.6  54.7  195   9  5   8.2   4.5 |  12.4  54.3  195  10  5   8.3   4.6
 11000  13.8  56.8  195   8  4   7.7   4.2 |  13.7  56.7  195   9  5   8.1   4.5
 10500  14.9  58.8  195   8  4   2.8   1.5 |  14.8  58.6  195   8  4   3.6   2.0
 10250  15.0  59.0  195   7  4   4.2   2.3 |  15.0  59.0  195   7  4   5.4   3.0
 10000  15.7  60.3  200   7  3  11.1   6.1 |  15.7  60.3  200   6  3  11.2   6.2
  9750  16.4  61.5  205   6  3   9.7   5.3 |  16.5  61.7  205   5  3   9.9   5.4
  9500  17.1  62.8  210   5  3   7.3   4.0 |  17.2  63.0  210   4  2   7.7   4.2
  9250  17.4  63.3  210   5  2   4.7   2.6 |  17.6  63.7  220   3  2   5.9   3.2
  9000  17.9  64.2  215   4  2   6.9   3.8 |  18.1  64.6  230   2  1   7.8   4.3
  8750  18.4  65.1  220   3  2   7.6   4.1 |  18.7  65.7  260   2  1   8.2   4.5
  8500  18.9  66.0  230   2  1   6.1   3.4 |  19.3  66.7  295   2  1   6.9   3.8
  8250  19.3  66.7  245   1  1   5.3   2.9 |  19.7  67.5  325   2  1   6.2   3.4
  8000  19.6  67.3  285   1  0   5.5   3.0 |  20.2  68.4  345   2  1   6.5   3.6
  7750  20.0  68.0  330   1  1   4.4   2.4 |  20.6  69.1  005   3  2   6.9   3.8
  7500  20.3  68.5  340   2  1   2.1   1.2 |  21.2  70.2  010   3  2   7.5   4.1
  7250  20.3  68.5  335   3  1   1.2   0.7 |  21.7  71.1  010   3  2   7.9   4.3
  7000  20.4  68.7  330   4  2   1.3   0.7 |  22.3  72.1  010   3  2   7.3   4.0
  6750  20.5  68.9  325   5  2   0.9   0.5 |  22.8  73.0  010   3  2   9.1   5.0
  6500  20.6  69.1  320   5  2   1.2   0.7 |  23.6  74.5  010   3  2  11.1   6.1
  6250  20.6  69.1  310   4  2   0.7   0.4 |  24.4  75.9  010   3  2  10.9   6.0
  6000  20.7  69.3  295   4  2   2.8   1.5 |  25.2  77.4  010   3  1  11.0   6.0
  5750  21.1  70.0  295   4  2  10.9   6.0 |  26.2  79.2  010   3  1  17.2   9.5
  5500  22.2  72.0  290   3  2  17.7   9.7 |  27.9  82.2  010   3  1  27.5  15.1

           08/18/2025 at 1500 MDT          |       08/18/2025 at 1800 MDT
                                           |
CAPE...  +624.9    LI...       -4.2        | CAPE...  +125.8    LI...       -2.1
CINH...   -13.9    K Index... +33.8        | CINH...  -220.5    K Index... +31.0
                                           |
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 -64.4 -83.9  255  16  8   1.1   0.6 | -64.7 -84.5  265  13  6   0.4   0.2
 45000 -59.9 -75.8  270  30 15   6.5   3.6 | -60.4 -76.7  275  27 14   7.1   3.9
 40000 -49.3 -56.7  275  42 22   7.9   4.3 | -49.7 -57.5  275  41 21   7.5   4.1
 38000 -44.6 -48.3  275  42 22   7.9   4.3 | -44.6 -48.3  275  43 22   7.5   4.1
 36000 -39.9 -39.8  275  42 22   7.1   3.9 | -40.1 -40.2  275  44 23   6.4   3.5
 34000 -36.0 -32.8  270  36 19   6.5   3.6 | -36.4 -33.5  265  24 12   6.2   3.4
 32000 -32.1 -25.8  260  31 16   7.2   4.0 | -32.7 -26.9  215   8  4   8.0   4.4
 30000 -28.5 -19.3  250  27 14   6.0   3.3 | -27.7 -17.9  180   9  5   8.4   4.6
 29000 -26.7 -16.1  245  25 13   6.0   3.3 | -25.2 -13.4  170  11  5   8.4   4.6
 28000 -24.5 -12.1  240  23 12   5.4   3.0 | -23.0  -9.4  165  12  6   5.0   2.7
 27000 -22.9  -9.2  240  22 12   5.5   3.0 | -21.4  -6.5  175  12  6   5.4   2.9
 26000 -21.2  -6.2  235  22 11   5.5   3.0 | -19.8  -3.6  180  13  7   5.4   2.9
 25000 -19.5  -3.1  235  21 11   5.7   3.1 | -18.2  -0.8  185  14  7   5.9   3.3
 24000 -17.9  -0.2  240  19 10   5.8   3.2 | -16.2   2.8  195  13  6   6.6   3.6
 23000 -16.2   2.8  240  17  9   5.8   3.2 | -14.3   6.3  200  12  6   6.6   3.6
 22000 -14.4   6.1  245  15  8   7.6   4.2 | -12.3   9.9  210  11  6   6.4   3.5
 21000 -12.1  10.2  240  13  7   8.1   4.4 | -10.5  13.1  220  10  5   6.3   3.4
 20000  -9.7  14.5  235  12  6   8.2   4.5 |  -8.2  17.2  240   9  5   6.3   3.5
 19500  -8.6  16.5  235  11  6   8.3   4.5 |  -7.3  18.9  245   9  5   6.9   3.8
 19000  -7.3  18.9  230  11  6   8.5   4.7 |  -6.2  20.8  250   9  5   7.2   3.9
 18500  -6.1  21.0  225  11  6   8.5   4.6 |  -5.2  22.6  250   9  5   7.2   3.9
 18000  -4.8  23.4  220  11  6   8.9   4.9 |  -4.1  24.6  250   9  5   7.7   4.2
 17500  -3.5  25.7  215  11  6   8.9   4.9 |  -3.0  26.6  250   9  5   7.7   4.2
 17000  -2.2  28.0  210  11  6   8.9   4.9 |  -1.9  28.6  250   9  5   7.9   4.3
 16500  -0.9  30.4  205  12  6   8.8   4.8 |  -0.8  30.6  245   9  5   8.0   4.4
 16000   0.3  32.5  200  13  7   8.9   4.9 |   0.4  32.7  240   9  5   8.0   4.4
 15500   1.6  34.9  195  13  7   8.7   4.8 |   1.5  34.7  240   9  5   7.8   4.3
 15000   2.8  37.0  190  14  7   8.7   4.8 |   2.7  36.9  240   8  4   7.7   4.2
 14500   4.6  40.3  185  14  7   9.0   4.9 |   3.9  39.0  240   8  4   8.5   4.7
 14000   5.9  42.6  185  14  7   9.0   5.0 |   5.1  41.2  245   7  4   8.5   4.6
 13500   7.2  45.0  180  14  7   8.8   4.8 |   6.3  43.3  250   6  3   8.2   4.5
 13000   8.5  47.3  175  12  6   8.8   4.8 |   7.5  45.5  255   6  3   8.1   4.5
 12500   9.8  49.6  175  11  5   9.1   5.0 |   8.7  47.7  260   5  3   8.2   4.5
 12000  11.1  52.0  170   8  4   9.1   5.0 |   9.9  49.8  265   4  2   8.2   4.5
 11500  12.5  54.5  160   5  3   9.0   4.9 |  11.1  52.0  270   4  2   7.7   4.2
 11000  13.8  56.8  155   4  2   9.1   5.0 |  12.1  53.8  275   3  2   7.2   3.9
 10500  15.0  59.0  145   3  2   4.8   2.7 |  13.2  55.8  275   3  2   4.7   2.6
 10250  15.3  59.5  145   3  2   8.6   4.7 |  13.4  56.1  270   3  2   5.7   3.1
 10000  16.2  61.2  145   3  2  13.3   7.3 |  14.1  57.4  265   3  1   9.9   5.4
  9750  17.1  62.8  145   3  1  11.9   6.5 |  14.7  58.5  260   2  1   9.3   5.1
  9500  18.0  64.4  145   3  1   9.5   5.2 |  15.4  59.7  255   2  1   7.7   4.2
  9250  18.6  65.5  145   3  1   8.6   4.7 |  15.9  60.6  240   2  1   6.0   3.3
  9000  19.3  66.7  145   3  1  10.6   5.8 |  16.4  61.5  225   2  1   7.8   4.3
  8750  20.1  68.2  150   2  1  10.7   5.9 |  17.0  62.6  210   2  1   8.6   4.7
  8500  20.9  69.6  150   2  1   9.9   5.4 |  17.7  63.9  195   3  1   7.7   4.2
  8250  21.6  70.9  150   2  1   9.4   5.2 |  18.2  64.8  185   3  2   7.7   4.2
  8000  22.4  72.3  150   2  1  10.0   5.5 |  18.7  65.7  175   4  2   6.3   3.5
  7750  23.1  73.6  150   2  1  10.4   5.7 |  19.1  66.4  170   4  2   3.9   2.1
  7500  23.9  75.0  150   2  1  10.2   5.6 |  19.4  66.9  175   5  2   3.6   2.0
  7250  24.6  76.3  150   2  1  10.3   5.7 |  19.6  67.3  185   5  3   3.4   1.9
  7000  25.4  77.7  150   2  1  10.0   5.5 |  19.8  67.6  190   6  3   4.2   2.3
  6750  26.1  79.0  155   1  1  10.1   5.5 |  20.1  68.2  195   6  3   2.7   1.5
  6500  26.9  80.4  155   1  1  10.6   5.8 |  20.1  68.2  200   7  4   0.5   0.3
  6250  27.7  81.9  155   1  1  10.4   5.7 |  20.1  68.2  210   9  4  -0.2  -0.1
  6000  28.5  83.3  155   1  1  11.2   6.2 |  20.1  68.2  215  10  5   3.0   1.6
  5750  29.5  85.1  155   1  1  18.0   9.9 |  20.6  69.1  210   9  5  10.6   5.8
  5500  31.2  88.2  160   1  0  26.5  14.5 |  21.4  70.5  200   7  4  13.5   7.4
________________________________________________________________________________

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