Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 191233
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0633 MDT Monday, June 19, 2017

This forecast is for Monday, June 19, 2017:

If the trigger temperature of 70.3 F/21.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 567 ft/min (2.9 m/s)
   Maximum height of thermals.................. 13759 ft MSL (8474 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 C
Time of trigger temperature.................... 0945 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................. 12982 ft MSL (7697 ft AGL)
Thermal soaring outlook for Tuesday 06/20...... Excellent

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 13634 ft MSL (8349 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 25421 ft MSL (20136 ft AGL)
Wave soaring outlook for Tuesday 06/20......... Poor

Remarks...

Sunrise/Sunset.................... 05:31:18 / 20:30:35 MDT
Total possible sunshine........... 14 hr 59 min 17 sec (899 min 17 sec)
Altitude of sun at 13:00:56 MDT... 73.66 degrees

Upper air data from rawinsonde observation taken on 06/19/2017 at 0600 MDT

Freezing level.................. 15861 ft MSL (10576 ft AGL)
Convective condensation level... 17053 ft MSL (11768 ft AGL)
Lifted condensation level....... 16131 ft MSL (10845 ft AGL)
Lifted index.................... +2.5
K index......................... +7.4

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  -71.3 -96.3   310   42   22  -2.4  -1.3   75.0 167.0    26.1      M    M
 45000  -67.3 -89.1   305   47   24   8.0   4.4   56.8 134.3    16.8      M    M
 40000  -55.1 -67.2   300   49   25   7.5   4.1   52.4 126.3    15.0      M    M
 38000  -50.0 -58.0   305   48   25   8.6   4.7   51.1 123.9    14.5      M    M
 36000  -44.8 -48.6   305   47   24   8.6   4.7   50.4 122.6    14.4      M    M
 34000  -39.7 -39.5   310   45   23   8.5   4.7   49.2 120.6    13.9      M    M
 32000  -34.7 -30.5   320   43   22   8.5   4.6   48.3 118.9    13.6      M    M
 30000  -29.5 -21.1   325   45   23   8.6   4.7   47.5 117.4    13.3      M    M
 29000  -27.0 -16.6   325   46   24   8.6   4.7   46.9 116.4    13.0      M    M
 28000  -24.4 -11.9   325   48   25   8.6   4.7   46.4 115.6    12.8      M    M
 27000  -21.4  -6.5   325   49   25   7.2   3.9   45.6 114.1    12.3      M    M
 26000  -19.3  -2.7   325   51   26   7.1   3.9   44.6 112.2    11.6      M    M
 25000  -17.2   1.0   325   52   27   7.4   4.0   43.7 110.6    11.0      M    M
 24000  -14.8   5.4   325   51   26   7.7   4.2   42.8 109.0    10.5      M    M
 23000  -12.5   9.5   325   51   26   7.7   4.2   42.0 107.7    10.0      M    M
 22000  -10.2  13.6   330   50   26   7.7   4.2   41.4 106.5     9.5      M    M
 21000   -7.9  17.8   330   50   26   7.7   4.2   40.9 105.6     9.2      M    M
 20000   -5.6  21.9   325   46   24   7.7   4.2   40.1 104.2     8.7      M    M
 19500   -4.4  24.1   320   45   23   7.3   4.0   39.7 103.5     8.4      M    M
 19000   -4.0  24.8   320   43   22  -1.5  -0.8   38.5 101.2     7.3      M    M
 18500   -3.9  25.0   320   41   21 -14.3  -7.9   37.0  98.5     6.0      M    M
 18000   -5.1  22.8   320   40   20  12.3   6.8   34.0  93.2     3.3      M    M
 17500   -4.0  24.8   320   38   19   8.2   4.5   33.7  92.6     3.0      M    M
 17000   -2.8  27.0   320   36   19   7.9   4.3   33.4  92.1     2.7      M    M
 16500   -1.7  28.9   320   34   18   7.9   4.3   33.1  91.5     2.5      M    M
 16000   -0.5  31.1   320   32   17   7.9   4.3   32.8  91.1     2.2      M    M
 15500    0.6  33.1   320   32   16   8.0   4.4   32.5  90.5     1.9      M    M
 15000    1.8  35.2   320   31   16   8.0   4.4   32.1  89.9     1.6      M    M
 14500    2.9  37.2   315   31   16   7.9   4.3   31.8  89.3     1.2      M    M
 14000    4.3  39.7   315   29   15   0.3   0.2   31.1  88.0     0.5      M    M
 13500    3.9  39.0   310   27   14  -1.6  -0.9   29.1  84.5    -1.4    566  2.9
 13000    3.5  38.3   310   24   12   0.5   0.3   27.3  81.1    -3.3    564  2.9
 12500    4.1  39.4   305   22   11   5.3   2.9   26.4  79.5    -4.2    531  2.7
 12000    4.8  40.6   300   19   10   5.3   2.9   25.7  78.2    -4.9    493  2.5
 11500    5.6  42.1   295   16    8   5.3   2.9   24.9  76.9    -5.7    456  2.3
 11000    6.4  43.5   295   12    6   5.3   2.9   24.2  75.6    -6.4    418  2.1
 10500    7.1  44.8   285    8    4   5.3   2.9   23.5  74.3    -7.1    380  1.9
 10250    7.5  45.5   285    8    4   5.4   2.9   23.2  73.7    -7.4    362  1.8
 10000    7.9  46.2   285    8    4   5.2   2.8   22.8  73.1    -7.8    343  1.7
  9750    8.3  46.9   295    7    3   7.0   3.9   22.5  72.5    -8.2    323  1.6
  9500    8.9  48.0   310    6    3   8.6   4.7   22.4  72.3    -8.3    297  1.5
  9250    9.5  49.1   330    5    3   8.2   4.5   22.3  72.1    -8.4    271  1.4
  9000   10.2  50.4   345    5    3   8.3   4.5   22.2  71.9    -8.5    245  1.2
  8750   10.8  51.4   005    5    3   8.2   4.5   22.0  71.7    -8.7    219  1.1
  8500   11.4  52.5   020    5    3   8.3   4.5   21.9  71.5    -8.8    193  1.0
  8250   12.0  53.6   035    6    3   8.2   4.5   21.8  71.2    -8.9    167  0.8
  8000   12.6  54.7   045    7    4   8.6   4.7   21.7  71.0    -9.0    141  0.7
  7750   13.3  55.9   035    7    4   7.1   3.9   21.6  70.8    -9.2    115  0.6
  7500   13.7  56.7   030    7    3   5.1   2.8   21.3  70.3    -9.5     95  0.5
  7250   14.0  57.2   020    7    4   5.1   2.8   20.9  69.6    -9.9     77  0.4
  7000   14.4  57.9   015    7    4   5.2   2.8   20.6  69.0   -10.3     59  0.3
  6750   14.7  58.5   005    8    4   5.2   2.8   20.2  68.4   -10.7     41  0.2
  6500   15.1  59.2   360    8    4   5.1   2.8   19.9  67.7   -11.1     24  0.1
  6250   15.4  59.7   355    9    5   5.3   2.9   19.5  67.1   -11.5      6  0.0
  6000   15.8  60.4   350   10    5   4.8   2.6   19.2  66.5   -11.9      M    M
  5750   16.1  61.0   350    7    4   6.8   3.8   18.8  65.9   -12.4      M    M
  5500   16.5  61.7   350    3    2  -0.8  -0.5   18.5  65.3   -12.8      M    M

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

           06/19/2017 at 0900 MDT          |       06/19/2017 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +5.5        | CAPE...     0.0    LI...       +3.7
CINH...     0.0    K Index...  +9.1        | CINH...     0.0    K Index...  +8.5
                                           |
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 -66.7 -88.1  310  18  9  -1.2  -0.7 | -66.4 -87.5  305  16  8  -0.4  -0.2
 45000 -65.5 -85.9  300  25 13   6.2   3.4 | -64.3 -83.7  305  24 13   5.3   2.9
 40000 -55.9 -68.6  305  24 12   8.1   4.4 | -55.8 -68.4  305  24 13   8.2   4.5
 38000 -50.4 -58.7  305  24 12   8.1   4.5 | -50.8 -59.4  310  24 12   8.3   4.5
 36000 -45.5 -49.9  310  23 12   8.2   4.5 | -45.9 -50.6  310  24 12   8.3   4.5
 34000 -40.4 -40.7  310  23 12   8.4   4.6 | -40.9 -41.6  310  23 12   8.4   4.6
 32000 -35.3 -31.5  310  22 12   8.6   4.7 | -35.9 -32.6  310  22 12   8.3   4.6
 30000 -30.3 -22.5  310  22 11   8.4   4.6 | -30.3 -22.5  310  21 11   8.2   4.5
 29000 -27.7 -17.9  310  21 11   8.4   4.6 | -27.8 -18.0  310  21 11   8.2   4.5
 28000 -25.2 -13.4  315  21 11   8.3   4.5 | -25.4 -13.7  310  20 10   8.2   4.5
 27000 -22.7  -8.9  315  21 11   8.3   4.5 | -22.9  -9.2  310  19 10   8.2   4.5
 26000 -20.3  -4.5  315  20 10   8.3   4.5 | -20.5  -4.9  310  18  9   8.2   4.5
 25000 -17.8  -0.0  315  20 10   8.2   4.5 | -18.0  -0.4  315  18  9   8.1   4.4
 24000 -15.4   4.3  320  20 10   8.0   4.4 | -15.7   3.7  315  17  9   8.0   4.4
 23000 -13.0   8.6  320  20 10   8.0   4.4 | -13.3   8.1  320  17  9   8.0   4.4
 22000 -10.6  12.9  320  20 10   7.6   4.2 | -10.9  12.4  320  16  8   7.5   4.1
 21000  -8.5  16.7  325  19 10   6.8   3.7 |  -8.8  16.2  320  16  8   7.2   4.0
 20000  -6.5  20.3  325  19 10   6.8   3.8 |  -6.6  20.1  325  15  8   7.2   4.0
 19500  -5.0  23.0  325  19 10   6.4   3.5 |  -5.5  22.1  325  15  8   7.2   3.9
 19000  -4.1  24.6  325  19 10   5.7   3.1 |  -4.6  23.7  325  15  8   6.1   3.4
 18500  -3.2  26.2  325  18  9   5.7   3.2 |  -3.6  25.5  325  14  7   6.2   3.4
 18000  -2.4  27.7  320  18  9   5.2   2.8 |  -2.7  27.1  325  14  7   6.1   3.4
 17500  -1.7  28.9  320  18  9   5.2   2.8 |  -1.8  28.8  325  14  7   6.1   3.3
 17000  -1.9  28.6  320  18  9   5.2   2.8 |  -0.9  30.4  325  14  7   6.1   3.3
 16500  -0.2  31.6  320  17  9   5.1   2.8 |   0.4  32.7  320  13  7   6.0   3.3
 16000   0.5  32.9  320  17  9   5.2   2.9 |   1.2  34.2  320  13  7   6.0   3.3
 15500   1.2  34.2  320  16  8   4.9   2.7 |   2.1  35.8  320  13  7   5.9   3.3
 15000   1.9  35.4  320  15  8   5.0   2.7 |   2.9  37.2  315  13  7   6.0   3.3
 14500   2.6  36.7  320  15  8   4.9   2.7 |   3.7  38.7  315  12  6   5.4   3.0
 14000   3.3  37.9  320  14  7   4.9   2.7 |   4.5  40.1  310  12  6   5.5   3.0
 13500   3.9  39.0  320  13  7   5.0   2.7 |   5.2  41.4  305  12  6   5.5   3.0
 13000   4.6  40.3  320  12  6   5.0   2.8 |   6.0  42.8  305  11  6   5.5   3.0
 12500   5.3  41.5  320  11  6   5.4   2.9 |   6.7  44.1  300  10  5   5.9   3.2
 12000   6.1  43.0  320  10  5   5.9   3.2 |   7.6  45.7  295   9  5   6.2   3.4
 11500   6.9  44.4  325   9  5   6.0   3.3 |   8.4  47.1  295   9  4   6.1   3.3
 11000   7.8  46.0  325   8  4   6.3   3.4 |   9.3  48.7  295   7  4   6.0   3.3
 10500   8.7  47.7  325   8  4   6.4   3.5 |  10.1  50.2  295   6  3   6.7   3.7
 10250   9.2  48.6  325   7  4   6.2   3.4 |  10.6  51.1  300   5  2   6.7   3.7
 10000   9.6  49.3  325   6  3   5.3   2.9 |  11.0  51.8  300   4  2   5.6   3.0
  9750   9.9  49.8  325   6  3   5.2   2.9 |  11.4  52.5  305   3  2   5.8   3.2
  9500  10.3  50.5  320   5  3   4.5   2.4 |  11.8  53.2  315   3  1   5.3   2.9
  9250  10.6  51.1  320   5  2   3.2   1.8 |  12.2  54.0  320   2  1   4.8   2.7
  9000  10.8  51.4  315   4  2   4.0   2.2 |  12.6  54.7  335   2  1   6.8   3.7
  8750  11.1  52.0  315   3  2   4.8   2.6 |  13.1  55.6  005   1  1   8.1   4.5
  8500  11.4  52.5  315   3  1   4.2   2.3 |  13.7  56.7  045   1  1   8.2   4.5
  8250  11.7  53.1  325   2  1   4.0   2.2 |  14.3  57.7  065   2  1   8.6   4.7
  8000  12.0  53.6  335   1  1   3.8   2.1 |  14.9  58.8  080   2  1   8.7   4.7
  7750  12.2  54.0  015   1  0   3.7   2.0 |  15.6  60.1  080   2  1   9.3   5.1
  7500  12.5  54.5  045   1  0   4.9   2.7 |  16.3  61.3  080   2  1   9.9   5.4
  7250  12.9  55.2  055   1  1   5.4   3.0 |  17.0  62.6  080   3  1  10.0   5.5
  7000  13.3  55.9  065   1  1   5.4   3.0 |  17.8  64.0  080   3  1  10.0   5.5
  6750  13.8  56.8  070   1  1   8.0   4.4 |  18.5  65.3  080   3  1  10.4   5.7
  6500  14.4  57.9  065   1  1   9.3   5.1 |  19.3  66.7  080   3  1  10.6   5.8
  6250  15.1  59.2  065   1  1   9.7   5.3 |  20.1  68.2  080   3  1  10.5   5.7
  6000  15.8  60.4  070   1  1   6.2   3.4 |  20.9  69.6  080   3  1  10.8   5.9
  5750  16.2  61.2  075   1  1  10.5   5.7 |  21.8  71.2  080   3  1  17.9   9.8
  5500  17.7  63.9  070   1  1  28.6  15.7 |  23.6  74.5  080   3  1  28.9  15.8

           06/19/2017 at 1500 MDT          |       06/19/2017 at 1800 MDT
                                           |
CAPE...   +80.2    LI...       +1.6        | CAPE...  +289.2    LI...       +0.8
CINH...  -156.8    K Index... +16.9        | CINH...  -129.5    K Index... +22.7
                                           |
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 -66.2 -87.2  305  16  8   0.5   0.3 | -66.0 -86.8  305  17  9   1.0   0.5
 45000 -63.3 -81.9  310  23 12   5.0   2.7 | -62.7 -80.9  310  23 12   4.8   2.6
 40000 -55.3 -67.5  300  24 12   7.7   4.2 | -55.0 -67.0  300  26 13   7.4   4.1
 38000 -50.6 -59.1  305  24 12   7.8   4.3 | -50.5 -58.9  300  25 13   7.5   4.1
 36000 -46.0 -50.8  305  24 12   7.8   4.3 | -46.0 -50.8  305  25 13   7.5   4.1
 34000 -41.1 -42.0  305  23 12   8.2   4.5 | -40.5 -40.9  305  24 12   8.2   4.5
 32000 -35.6 -32.1  305  22 11   8.4   4.6 | -35.6 -32.1  305  23 12   8.5   4.7
 30000 -30.7 -23.3  310  20 10   8.1   4.5 | -30.7 -23.3  305  21 11   8.2   4.5
 29000 -28.3 -18.9  310  19 10   8.1   4.5 | -28.2 -18.8  305  20 10   8.2   4.5
 28000 -25.8 -14.4  310  19 10   8.1   4.5 | -25.8 -14.4  305  19 10   8.3   4.5
 27000 -23.4 -10.1  310  18  9   8.1   4.5 | -23.3  -9.9  305  18  9   8.3   4.5
 26000 -21.0  -5.8  310  17  9   8.1   4.5 | -20.8  -5.4  305  17  9   8.3   4.5
 25000 -18.5  -1.3  310  16  8   8.1   4.5 | -18.3  -0.9  310  16  8   8.2   4.5
 24000 -16.1   3.0  310  15  8   8.1   4.4 | -15.9   3.4  305  16  8   8.2   4.5
 23000 -13.7   7.3  310  14  7   8.1   4.4 | -13.4   7.9  305  15  8   8.2   4.5
 22000 -11.3  11.7  310  13  7   7.7   4.2 | -11.0  12.2  305  15  8   7.8   4.3
 21000  -9.0  15.8  315  13  6   7.5   4.1 |  -8.7  16.3  300  14  7   7.5   4.1
 20000  -6.8  19.8  315  12  6   7.5   4.1 |  -6.5  20.3  300  14  7   7.5   4.1
 19500  -5.7  21.7  315  12  6   7.5   4.1 |  -5.4  22.3  295  14  7   7.5   4.1
 19000  -4.6  23.7  315  12  6   7.0   3.8 |  -4.4  24.1  295  14  7   6.5   3.5
 18500  -3.6  25.5  310  12  6   7.0   3.8 |  -2.9  26.8  290  14  7   6.6   3.6
 18000  -2.6  27.3  310  12  6   6.6   3.6 |  -2.0  28.4  285  14  7   6.7   3.7
 17500  -1.2  29.8  305  12  6   6.4   3.5 |  -1.0  30.2  285  14  7   6.8   3.7
 17000  -0.3  31.5  300  12  6   6.3   3.5 |  -0.1  31.8  280  14  7   6.5   3.6
 16500   0.6  33.1  295  12  6   6.3   3.4 |   0.8  33.4  280  14  7   6.4   3.5
 16000   1.5  34.7  295  12  6   6.4   3.5 |   1.7  35.1  280  13  7   6.6   3.6
 15500   2.4  36.3  290  12  6   6.5   3.6 |   2.6  36.7  280  13  7   7.1   3.9
 15000   3.3  37.9  285  12  6   6.5   3.6 |   3.6  38.5  280  12  6   7.1   3.9
 14500   4.3  39.7  285  12  6   7.3   4.0 |   4.6  40.3  280  11  6   7.5   4.1
 14000   5.3  41.5  280  11  6   7.4   4.0 |   5.6  42.1  280  10  5   7.6   4.1
 13500   6.3  43.3  280  11  6   7.1   3.9 |   6.7  44.1  275   9  4   7.3   4.0
 13000   7.3  45.1  275  10  5   7.1   3.9 |   7.7  45.9  270   7  3   7.2   4.0
 12500   8.3  46.9  275   9  5   6.9   3.8 |   8.7  47.7  265   5  3   7.2   3.9
 12000   9.2  48.6  275   7  4   6.8   3.7 |   9.7  49.5  250   3  2   7.1   3.9
 11500  10.2  50.4  270   5  3   6.5   3.5 |  10.8  51.4  215   2  1   7.1   3.9
 11000  11.0  51.8  270   3  2   6.1   3.4 |  11.8  53.2  170   2  1   7.2   4.0
 10500  11.9  53.4  260   1  0   7.2   3.9 |  12.8  55.0  130   3  1   8.8   4.8
 10250  12.5  54.5  115   1  0   7.8   4.3 |  13.5  56.3  120   3  2   9.7   5.3
 10000  13.0  55.4  100   1  1   6.8   3.7 |  14.2  57.6  120   3  2   8.4   4.6
  9750  13.5  56.3  090   2  1   6.9   3.8 |  14.8  58.6  115   3  2   8.7   4.8
  9500  14.0  57.2  090   2  1   7.6   4.2 |  15.5  59.9  115   3  2   8.8   4.9
  9250  14.6  58.3  090   2  1   8.8   4.8 |  16.2  61.2  110   4  2   9.4   5.2
  9000  15.3  59.5  085   3  1   9.9   5.4 |  16.9  62.4  110   4  2   9.8   5.4
  8750  16.1  61.0  085   3  1  10.7   5.9 |  17.6  63.7  110   4  2  10.0   5.5
  8500  16.9  62.4  085   3  1  10.2   5.6 |  18.4  65.1  110   4  2  10.3   5.6
  8250  17.6  63.7  085   3  2  10.3   5.7 |  19.2  66.6  105   4  2  11.0   6.0
  8000  18.4  65.1  085   3  2   9.7   5.3 |  20.0  68.0  105   4  2   9.7   5.3
  7750  19.1  66.4  085   3  2   9.2   5.0 |  20.6  69.1  105   4  2   8.6   4.7
  7500  19.8  67.6  080   3  2  10.1   5.6 |  21.3  70.3  105   4  2  10.0   5.5
  7250  20.6  69.1  080   3  2  10.8   5.9 |  22.1  71.8  100   4  2  11.0   6.0
  7000  21.3  70.3  080   4  2   9.9   5.4 |  22.9  73.2  100   4  2   9.9   5.4
  6750  22.1  71.8  080   4  2   9.5   5.2 |  23.6  74.5  100   4  2   8.8   4.8
  6500  22.8  73.0  080   3  2  10.2   5.6 |  24.3  75.7  100   4  2   9.7   5.3
  6250  23.6  74.5  080   3  2  10.8   5.9 |  25.0  77.0  100   4  2  10.8   5.9
  6000  24.4  75.9  080   3  2   9.6   5.2 |  25.8  78.4  095   4  2   9.1   5.0
  5750  25.2  77.4  080   4  2  17.0   9.3 |  26.5  79.7  100   4  2  12.8   7.0
  5500  27.1  80.8  075   3  2  32.5  17.8 |  27.8  82.0  095   3  2  23.1  12.6
________________________________________________________________________________

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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