Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 021252
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0651 MDT Thursday, July 2, 2020

This forecast is for Thursday, July 2, 2020:

If the trigger temperature of 82.7 F/28.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1507 ft/min (7.7 m/s)
   Maximum height of thermals.................. 21047 ft MSL (15762 ft AGL)

Forecast maximum temperature................... 94.0 F/34.9 C
Time of trigger temperature.................... 1030 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................. 17053 ft MSL (11767 ft AGL)
Thermal soaring outlook for Friday 07/03....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 17088 ft MSL (11803 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 17580 ft MSL (12295 ft AGL)
Wave soaring outlook for Friday 07/03.......... Poor

Remarks...

Sunrise/Sunset.................... 05:36:06 / 20:31:18 MDT
Total possible sunshine........... 14 hr 55 min 12 sec (895 min 12 sec)
Altitude of sun at 13:03:42 MDT... 73.17 degrees

Upper air data from rawinsonde observation taken on 07/02/2020 at 0600 MDT

Freezing level.................. 15397 ft MSL (10112 ft AGL)
Convective condensation level... 18427 ft MSL (13142 ft AGL)
Lifted condensation level....... 19116 ft MSL (13831 ft AGL)
Lifted index.................... -3.2
K index......................... +9.2

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  -62.1 -79.8   245   31   16   2.0   1.1   90.6 195.2    32.6      M    M
 45000  -58.4 -73.1   250   39   20   3.9   2.1   72.3 162.2    23.6      M    M
 40000  -54.3 -65.7   235   55   28   0.4   0.2   55.1 131.2    13.8      M    M
 38000  -53.8 -64.8   235   52   27   5.7   3.2   47.1 116.8     8.7      M    M
 36000  -49.6 -57.3   230   49   25   8.0   4.4   44.8 112.6     7.3      M    M
 34000  -44.9 -48.8   230   43   22   7.8   4.3   43.1 109.6     6.3      M    M
 32000  -40.4 -40.7   225   36   19   4.5   2.5   41.4 106.5     5.1      M    M
 30000  -36.1 -33.0   220   31   16   8.8   4.8   39.5 103.1     3.8      M    M
 29000  -32.8 -27.0   220   29   15   8.8   4.8   38.7 101.7     3.3      M    M
 28000  -30.1 -22.2   215   28   14   8.8   4.8   38.3 100.9     3.0      M    M
 27000  -27.5 -17.5   215   26   13   8.8   4.8   37.9 100.3     2.7      M    M
 26000  -24.8 -12.6   210   24   13   8.8   4.8   37.7  99.8     2.6      M    M
 25000  -22.2  -8.0   210   23   12   8.8   4.8   37.5  99.6     2.5      M    M
 24000  -19.8  -3.6   210   21   11   7.7   4.3   36.7  98.0     1.8      M    M
 23000  -17.5   0.5   210   19   10   7.8   4.3   35.8  96.5     1.1      M    M
 22000  -15.2   4.6   210   17    9   7.8   4.3   35.1  95.2     0.5      M    M
 21000  -12.9   8.8   210   14    7   7.8   4.3   34.5  94.1    -0.0   1504  7.6
 20000  -10.5  13.1   210   12    6   7.7   4.3   34.0  93.2    -0.5   1405  7.1
 19500   -9.4  15.1   210   14    7   7.6   4.2   33.6  92.5    -0.8   1355  6.9
 19000   -8.1  17.4   215   16    8   9.3   5.1   33.3  92.0    -1.0   1303  6.6
 18500   -6.7  19.9   220   18    9   9.1   5.0   33.3  91.9    -1.1   1247  6.3
 18000   -5.6  21.9   225   21   11   7.1   3.9   32.9  91.3    -1.4   1197  6.1
 17500   -4.5  23.9   230   24   12   8.4   4.6   32.5  90.5    -1.8   1151  5.8
 17000   -4.2  24.4   235   26   14   0.1   0.0   31.4  88.4    -2.9   1125  5.7
 16500   -3.2  26.2   235   25   13   9.2   5.1   30.9  87.6    -3.4   1082  5.5
 16000   -1.9  28.6   240   23   12   8.9   4.9   30.8  87.4    -3.6   1028  5.2
 15500   -0.6  30.9   240   20   10   8.9   4.9   30.7  87.2    -3.7    973  4.9
 15000    0.7  33.3   240   17    9   8.9   4.9   30.5  86.9    -3.9    919  4.7
 14500    2.7  36.9   235   13    7   8.9   4.9   30.4  86.7    -4.0    837  4.3
 14000    4.1  39.4   235   11    6   8.9   4.9   30.3  86.5    -4.2    783  4.0
 13500    5.4  41.7   235   10    5   8.9   4.9   30.1  86.2    -4.4    728  3.7
 13000    6.7  44.1   235    9    5   9.0   4.9   30.0  85.9    -4.5    674  3.4
 12500    8.0  46.4   235    8    4   9.0   4.9   29.8  85.7    -4.7    619  3.1
 12000    9.3  48.7   235    7    4   9.0   4.9   29.7  85.5    -4.8    565  2.9
 11500   10.7  51.3   240   10    5   9.0   4.9   29.6  85.2    -5.0    510  2.6
 11000   12.0  53.6   245   12    6   9.0   4.9   29.4  84.9    -5.2    456  2.3
 10500   13.3  55.9   245   14    7   8.9   4.9   29.3  84.7    -5.4    401  2.0
 10250   14.0  57.2   245   16    8   8.7   4.7   29.2  84.5    -5.5    375  1.9
 10000   14.6  58.3   245   16    8   8.5   4.7   29.1  84.3    -5.6    348  1.8
  9750   15.2  59.4   240   17    9   8.7   4.8   29.0  84.2    -5.7    322  1.6
  9500   15.9  60.6   240   18    9   8.2   4.5   28.9  84.0    -5.9    296  1.5
  9250   16.4  61.5   240   19   10   6.6   3.6   28.7  83.7    -6.1    272  1.4
  9000   16.8  62.2   240   20   10   5.9   3.2   28.5  83.2    -6.4    252  1.3
  8750   17.3  63.1   235   19   10   6.1   3.3   28.2  82.7    -6.7    232  1.2
  8500   17.7  63.9   235   18    9   6.1   3.3   27.9  82.2    -7.0    212  1.1
  8250   18.1  64.6   230   18    9   6.1   3.3   27.6  81.7    -7.3    191  1.0
  8000   18.5  65.3   225   17    9   6.1   3.3   27.3  81.2    -7.6    171  0.9
  7750   19.0  66.2   225   16    8   6.1   3.4   27.1  80.7    -7.9    151  0.8
  7500   19.4  66.9   225   15    8   6.1   3.4   26.8  80.2    -8.3    131  0.7
  7250   19.8  67.6   220   14    7   6.2   3.4   26.5  79.7    -8.6    110  0.6
  7000   20.3  68.5   220   13    7   6.1   3.3   26.2  79.2    -8.9     90  0.5
  6750   20.7  69.3   220   13    7   6.4   3.5   25.9  78.7    -9.2     70  0.4
  6500   21.1  70.0   215   13    7   5.2   2.9   25.7  78.2    -9.6     50  0.3
  6250   21.5  70.7   215   13    7   9.9   5.4   25.4  77.7    -9.9     29  0.1
  6000   22.0  71.6   210   13    7  -7.6  -4.2   25.1  77.3   -10.2      9  0.0
  5750   19.9  67.8   200   10    5 -17.3  -9.5   23.0  73.4   -13.0     63  0.3
  5500   19.7  67.5   185    8    4  19.0  10.4   22.2  72.0   -14.0     62  0.3

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

           07/02/2020 at 0900 MDT          |       07/02/2020 at 1200 MDT
                                           |
CAPE...   +51.4    LI...       +1.2        | CAPE...   +24.8    LI...       +0.9
CINH...   -79.7    K Index... +11.0        | CINH...   -12.0    K Index... +16.4
                                           |
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 -61.3 -78.3  240  14  7   0.9   0.5 | -62.1 -79.8  245  15  8   1.1   0.6
 45000 -58.9 -74.0  250  21 11   3.6   2.0 | -59.3 -74.7  255  21 11   3.6   2.0
 40000 -53.5 -64.3  245  21 11   4.6   2.5 | -53.7 -64.7  260  21 11   5.5   3.0
 38000 -50.8 -59.4  245  20 10   4.5   2.5 | -50.5 -58.9  265  19 10   5.4   3.0
 36000 -48.1 -54.6  240  18  9   4.5   2.5 | -47.2 -53.0  275  17  9   5.4   3.0
 34000 -44.5 -48.1  240  16  8   6.7   3.7 | -43.2 -45.8  270  14  7   7.1   3.9
 32000 -40.5 -40.9  235  15  7   6.7   3.7 | -38.4 -37.1  260  11  6   7.1   3.9
 30000 -35.2 -31.4  230  13  7   8.2   4.5 | -34.2 -29.6  245  11  5   7.0   3.8
 29000 -32.7 -26.9  230  13  6   8.2   4.5 | -32.1 -25.8  240  11  6   7.0   3.9
 28000 -30.3 -22.5  225  12  6   8.3   4.5 | -30.0 -22.0  235  11  6   7.9   4.3
 27000 -27.8 -18.0  225  11  6   8.3   4.6 | -27.5 -17.5  230  11  6   8.4   4.6
 26000 -25.3 -13.5  225  11  6   8.3   4.6 | -25.0 -13.0  230  11  6   8.4   4.6
 25000 -22.8  -9.0  225  10  5   8.3   4.6 | -22.5  -8.5  230  11  6   8.3   4.6
 24000 -20.5  -4.9  225  10  5   7.5   4.1 | -20.3  -4.5  230  12  6   7.3   4.0
 23000 -18.3  -0.9  220  10  5   7.5   4.1 | -18.1  -0.6  225  12  6   7.3   4.0
 22000 -16.1   3.0  220  11  5   7.5   4.1 | -15.9   3.4  225  12  6   7.4   4.0
 21000 -13.9   7.0  220  11  5   7.5   4.1 | -13.7   7.3  220  12  6   7.6   4.1
 20000 -11.6  11.1  225  11  6   7.5   4.1 | -11.4  11.5  220  12  6   7.6   4.2
 19500 -10.5  13.1  225  11  6   7.5   4.1 | -10.3  13.5  220  12  6   7.6   4.2
 19000  -9.4  15.1  225  11  6   7.8   4.3 |  -9.2  15.4  220  12  6   8.1   4.4
 18500  -8.3  17.1  230  11  6   7.9   4.3 |  -8.0  17.6  225  12  6   8.1   4.4
 18000  -7.1  19.2  235  11  6   8.0   4.4 |  -6.2  20.8  225  12  6   8.3   4.6
 17500  -5.3  22.5  235  12  6   8.2   4.5 |  -5.0  23.0  225  12  6   8.4   4.6
 17000  -4.1  24.6  235  12  6   8.4   4.6 |  -3.8  25.2  225  13  6   8.7   4.8
 16500  -2.9  26.8  235  12  6   8.5   4.7 |  -2.5  27.5  225  12  6   9.0   4.9
 16000  -1.6  29.1  235  13  7   8.5   4.7 |  -1.2  29.8  225  12  6   9.0   4.9
 15500  -0.3  31.5  235  13  7   9.0   4.9 |   0.2  32.4  225  12  6   9.4   5.2
 15000   1.0  33.8  235  13  6   8.9   4.9 |   1.5  34.7  225  11  6   9.4   5.1
 14500   2.3  36.1  235  12  6   9.1   5.0 |   2.9  37.2  225  11  6   9.4   5.1
 14000   3.7  38.7  235  12  6   9.1   5.0 |   4.3  39.7  225  10  5   9.4   5.1
 13500   5.0  41.0  235  11  6   9.1   5.0 |   5.7  42.3  225  10  5   9.3   5.1
 13000   6.4  43.5  235  11  5   9.1   5.0 |   7.1  44.8  225   9  5   9.3   5.1
 12500   7.7  45.9  235  10  5   9.1   5.0 |   8.5  47.3  220   9  5   9.4   5.1
 12000   9.1  48.4  235   9  5   9.0   5.0 |   9.9  49.8  220   8  4   9.5   5.2
 11500  10.4  50.7  240   9  4   9.1   5.0 |  11.3  52.3  220   7  4   9.4   5.1
 11000  11.8  53.2  240   8  4   9.0   4.9 |  12.7  54.9  220   7  3   8.9   4.9
 10500  13.2  55.8  240   7  4   5.8   3.2 |  14.1  57.4  220   6  3   5.9   3.2
 10250  13.5  56.3  240   7  4   6.7   3.7 |  14.4  57.9  215   5  3   7.1   3.9
 10000  14.3  57.7  240   7  4  11.6   6.4 |  15.2  59.4  215   5  3  11.9   6.5
  9750  15.1  59.2  240   7  4  10.8   5.9 |  16.0  60.8  215   5  2  11.2   6.2
  9500  15.9  60.6  240   7  3   9.1   5.0 |  16.8  62.2  215   4  2   9.1   5.0
  9250  16.4  61.5  245   7  3   6.5   3.6 |  17.4  63.3  210   4  2   7.4   4.0
  9000  16.9  62.4  245   6  3   8.9   4.9 |  18.0  64.4  210   4  2  10.4   5.7
  8750  17.7  63.9  245   6  3  10.9   6.0 |  18.9  66.0  210   4  2  11.6   6.3
  8500  18.5  65.3  245   6  3   8.9   4.9 |  19.7  67.5  210   4  2  10.4   5.7
  8250  19.0  66.2  250   6  3   6.9   3.8 |  20.4  68.7  205   3  2   9.2   5.0
  8000  19.5  67.1  250   6  3   7.1   3.9 |  21.1  70.0  200   3  1  10.0   5.5
  7750  20.1  68.2  250   5  3   8.4   4.6 |  21.9  71.4  205   3  1  10.9   6.0
  7500  20.6  69.1  255   5  3   4.3   2.4 |  22.7  72.9  205   3  1   9.9   5.5
  7250  20.6  69.1  255   5  2   0.3   0.2 |  23.4  74.1  205   3  1   9.1   5.0
  7000  20.7  69.3  260   4  2   1.8   1.0 |  24.1  75.4  200   2  1   9.8   5.4
  6750  20.8  69.4  265   4  2   3.8   2.1 |  24.9  76.8  200   2  1  10.9   6.0
  6500  21.2  70.2  260   3  2   5.7   3.1 |  25.7  78.3  205   2  1  10.7   5.9
  6250  21.5  70.7  260   3  1   6.1   3.3 |  26.5  79.7  200   2  1  10.8   5.9
  6000  21.9  71.4  260   2  1   5.0   2.7 |  27.3  81.1  200   2  1   9.3   5.1
  5750  22.3  72.1  260   2  1  10.4   5.7 |  28.0  82.4  200   2  1  14.3   7.9
  5500  23.5  74.3  255   2  1  23.1  12.6 |  29.6  85.3  200   2  1  28.5  15.6

           07/02/2020 at 1500 MDT          |       07/02/2020 at 1800 MDT
                                           |
CAPE...  +105.1    LI...       -0.4        | CAPE...  +165.9    LI...       +0.1
CINH...    -8.5    K Index... +17.7        | CINH...   -22.3    K Index... +20.0
                                           |
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 -62.8 -81.0  245  15  8   0.8   0.4 | -63.3 -81.9  245  14  7   0.5   0.3
 45000 -60.2 -76.4  255  22 11   3.7   2.1 | -60.7 -77.3  250  19 10   4.7   2.6
 40000 -54.2 -65.6  265  22 12   6.7   3.7 | -53.3 -63.9  255  21 11   6.6   3.6
 38000 -50.2 -58.4  265  20 11   6.6   3.6 | -49.3 -56.7  255  19 10   6.7   3.7
 36000 -46.3 -51.3  265  19 10   6.6   3.6 | -45.3 -49.5  255  18  9   6.7   3.7
 34000 -42.0 -43.6  265  16  8   7.3   4.0 | -40.7 -41.3  250  16  8   6.9   3.8
 32000 -37.1 -34.8  260  14  7   7.3   4.0 | -36.5 -33.7  250  15  8   6.8   3.7
 30000 -33.0 -27.4  250  12  6   6.8   3.8 | -32.2 -26.0  245  13  7   7.2   4.0
 29000 -30.9 -23.6  245  12  6   6.8   3.8 | -30.1 -22.2  245  12  6   7.3   4.0
 28000 -28.9 -20.0  240  11  6   6.7   3.7 | -27.9 -18.2  240  11  5   7.5   4.1
 27000 -26.9 -16.4  240  12  6   6.6   3.6 | -25.7 -14.3  240  10  5   7.6   4.2
 26000 -24.9 -12.8  240  12  6   6.7   3.7 | -23.4 -10.1  235  10  5   7.6   4.2
 25000 -23.0  -9.4  235  12  6   6.9   3.8 | -21.2  -6.2  230   9  5   7.5   4.1
 24000 -20.7  -5.3  235  12  6   8.1   4.4 | -19.0  -2.2  225   9  5   7.3   4.0
 23000 -18.3  -0.9  235  11  6   8.1   4.4 | -16.8   1.8  220   9  5   7.3   4.0
 22000 -15.9   3.4  235  10  5   8.2   4.5 | -14.7   5.5  215   9  5   7.5   4.1
 21000 -13.5   7.7  230  10  5   8.2   4.5 | -12.4   9.7  210   9  5   7.8   4.3
 20000 -11.1  12.0  225   9  5   8.2   4.5 | -10.1  13.8  200   9  5   7.8   4.3
 19500  -9.9  14.2  225   9  5   8.2   4.5 |  -9.0  15.8  200   9  5   7.8   4.3
 19000  -8.6  16.5  220   9  5   9.3   5.1 |  -7.2  19.0  195   8  4   8.2   4.5
 18500  -6.5  20.3  220   9  4   9.1   5.0 |  -6.0  21.2  190   8  4   8.2   4.5
 18000  -5.2  22.6  215   8  4   9.2   5.1 |  -4.7  23.5  185   8  4   8.9   4.9
 17500  -3.8  25.2  215   8  4   9.2   5.1 |  -3.4  25.9  185   8  4   8.9   4.9
 17000  -2.4  27.7  210   8  4   9.4   5.1 |  -2.1  28.2  185   8  4   9.3   5.1
 16500  -1.0  30.2  210   8  4   9.5   5.2 |  -0.7  30.7  185   7  4   9.6   5.3
 16000   0.4  32.7  210   8  4   9.5   5.2 |   0.8  33.4  180   7  4   9.6   5.3
 15500   1.8  35.2  210   7  4   9.6   5.3 |   2.2  36.0  180   7  3   9.5   5.2
 15000   3.2  37.8  205   7  4   9.6   5.3 |   3.6  38.5  180   6  3   9.5   5.2
 14500   4.7  40.5  205   7  4   9.6   5.3 |   5.1  41.2  180   6  3   9.7   5.3
 14000   6.1  43.0  205   7  3   9.6   5.3 |   6.5  43.7  180   5  3   9.7   5.3
 13500   7.5  45.5  205   6  3   9.6   5.3 |   7.9  46.2  175   5  3   9.5   5.2
 13000   9.0  48.2  205   6  3   9.6   5.3 |   9.3  48.7  175   4  2   9.4   5.1
 12500  10.4  50.7  200   6  3   9.7   5.3 |  10.7  51.3  175   4  2   9.3   5.1
 12000  11.8  53.2  200   6  3   9.7   5.3 |  12.1  53.8  175   3  2   9.3   5.1
 11500  13.3  55.9  200   5  3   9.8   5.4 |  13.5  56.3  170   2  1   9.3   5.1
 11000  14.8  58.6  200   5  3   9.7   5.3 |  14.9  58.8  170   2  1   8.9   4.9
 10500  16.2  61.2  200   5  3   7.2   4.0 |  16.3  61.3  175   1  0   6.1   3.3
 10250  16.7  62.1  195   5  2   8.0   4.4 |  16.6  61.9  000   0  0   6.7   3.7
 10000  17.5  63.5  195   5  2  11.7   6.4 |  17.3  63.1  000   0  0  10.8   5.9
  9750  18.3  64.9  195   5  2  11.2   6.2 |  18.1  64.6  000   0  0  10.3   5.7
  9500  19.2  66.6  195   5  2   9.5   5.2 |  18.8  65.8  330   1  0   8.3   4.5
  9250  19.8  67.6  195   4  2   8.4   4.6 |  19.3  66.7  345   1  1   6.5   3.6
  9000  20.5  68.9  195   4  2  10.6   5.8 |  19.9  67.8  345   2  1   9.2   5.1
  8750  21.3  70.3  195   4  2  11.1   6.1 |  20.7  69.3  335   2  1  10.3   5.7
  8500  22.1  71.8  195   4  2  10.6   5.8 |  21.4  70.5  330   2  1   9.2   5.1
  8250  22.9  73.2  195   4  2  10.0   5.5 |  22.0  71.6  330   3  1   7.6   4.2
  8000  23.6  74.5  190   4  2   9.9   5.4 |  22.6  72.7  330   3  2   8.4   4.6
  7750  24.4  75.9  195   4  2  10.0   5.5 |  23.3  73.9  325   4  2   9.6   5.3
  7500  25.1  77.2  195   4  2   9.9   5.4 |  24.0  75.2  320   4  2   8.9   4.9
  7250  25.9  78.6  195   4  2   9.7   5.3 |  24.6  76.3  320   4  2   8.2   4.5
  7000  26.6  79.9  190   4  2   9.9   5.4 |  25.2  77.4  320   4  2   9.0   5.0
  6750  27.3  81.1  190   4  2  10.5   5.7 |  26.0  78.8  320   5  2  10.9   6.0
  6500  28.1  82.6  195   4  2  10.6   5.8 |  26.8  80.2  315   5  2  10.5   5.8
  6250  28.9  84.0  190   4  2  11.0   6.0 |  27.5  81.5  315   5  2   9.7   5.3
  6000  29.7  85.5  190   3  2   9.6   5.3 |  28.2  82.8  315   5  2   9.5   5.2
  5750  30.5  86.9  190   3  2  13.4   7.4 |  28.9  84.0  315   5  2  11.0   6.0
  5500  32.0  89.6  190   3  2  27.0  14.8 |  29.9  85.8  315   4  2  16.2   8.9
________________________________________________________________________________

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


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