Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 201328
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0628 MST Saturday, January 20, 2018

This forecast is for Saturday, January 20, 2018:

If the trigger temperature of 62.6 F/17.0 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5681 ft MSL (357 ft AGL)

Forecast maximum temperature................... 49.0 F/9.9 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5474 ft MSL (150 ft AGL)
Thermal soaring outlook for Sunday 01/21....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 39477 ft MSL (34153 ft AGL)
Wave soaring outlook for Sunday 01/21.......... Poor

Remarks... Closed low moving into four corners area by Sunday morning, cold
           front pushing south this evening. Freezing drizzle then snow
           overnight into Sunday afternoon.

Sunrise/Sunset.................... 07:16:18 / 17:04:52 MST
Total possible sunshine........... 9 hr 48 min 34 sec (588 min 34 sec)
Altitude of sun at 12:10:35 MST... 30.18 degrees

Upper air data from numerical model forecast valid on 01/20/2018 at 0500 MST

Freezing level.................. 11309 ft MSL (5985 ft AGL)
Convective condensation level... 17660 ft MSL (12336 ft AGL)
Lifted condensation level....... 12440 ft MSL (7116 ft AGL)
Lifted index.................... +10.9
K index......................... +11.0

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  -62.6 -80.7   245   17    9  -2.8  -1.5      M     M       M      M    M
 45000  -67.0 -88.6   245   32   17  -2.0  -1.1      M     M       M      M    M
 40000  -63.3 -81.9   235   39   20   2.6   1.5      M     M       M      M    M
 38000  -60.2 -76.4   235   40   20   7.5   4.1      M     M       M      M    M
 36000  -55.7 -68.3   235   39   20   7.5   4.1      M     M       M      M    M
 34000  -51.2 -60.2   235   38   20   8.0   4.4      M     M       M      M    M
 32000  -46.4 -51.5   235   37   19   8.0   4.4      M     M       M      M    M
 30000  -41.0 -41.8   235   35   18   7.8   4.3   34.6  94.3    19.0      M    M
 29000  -38.7 -37.7   235   34   18   7.8   4.3   33.8  92.8    18.6      M    M
 28000  -36.4 -33.5   235   33   17   7.8   4.3   33.0  91.5    18.2      M    M
 27000  -34.1 -29.4   235   33   17   7.4   4.1   32.4  90.4    17.9      M    M
 26000  -31.9 -25.4   235   32   16   7.1   3.9   31.3  88.3    17.3      M    M
 25000  -29.8 -21.6   235   31   16   7.1   3.9   30.3  86.5    16.7      M    M
 24000  -27.7 -17.9   235   31   16   7.1   3.9   29.4  85.0    16.2      M    M
 23000  -25.6 -14.1   240   30   15   7.1   3.9   28.4  83.1    15.5      M    M
 22000  -23.4 -10.1   240   29   15   7.1   3.9   27.4  81.4    14.9      M    M
 21000  -21.3  -6.3   240   28   15   7.1   3.9   26.6  79.9    14.3      M    M
 20000  -19.2  -2.6   240   27   14   7.0   3.9   25.5  78.0    13.6      M    M
 19500  -18.2  -0.8   240   26   14   7.0   3.9   25.1  77.1    13.2      M    M
 19000  -17.1   1.2   240   26   13   7.1   3.9   24.6  76.3    12.9      M    M
 18500  -16.1   3.0   240   25   13   7.1   3.9   24.2  75.6    12.6      M    M
 18000  -15.1   4.8   240   24   12   7.0   3.9   23.7  74.7    12.3      M    M
 17500  -14.0   6.8   240   23   12   7.0   3.8   23.3  73.9    11.9      M    M
 17000  -13.0   8.6   240   22   11   7.3   4.0   22.8  73.1    11.6      M    M
 16500  -11.4  11.5   240   20   11   7.3   4.0   22.2  72.0    11.1      M    M
 16000  -10.2  13.6   240   19   10   7.8   4.3   21.8  71.3    10.8      M    M
 15500   -9.1  15.6   240   18    9   7.8   4.3   21.5  70.7    10.5      M    M
 15000   -8.0  17.6   240   17    9   7.6   4.2   21.2  70.1    10.3      M    M
 14500   -6.8  19.8   240   17    9   7.6   4.2   20.8  69.5    10.0      M    M
 14000   -5.7  21.7   240   17    9   7.4   4.1   20.5  68.8     9.7      M    M
 13500   -4.7  23.5   245   16    8   7.2   3.9   20.0  68.1     9.4      M    M
 13000   -3.6  25.5   245   16    8   7.2   3.9   19.6  67.3     9.0      M    M
 12500   -2.5  27.5   245   14    7   7.1   3.9   19.2  66.6     8.7      M    M
 12000   -1.5  29.3   245   13    7   7.2   4.0   18.8  65.8     8.3      M    M
 11500   -0.4  31.3   245   12    6   7.7   4.2   18.4  65.2     8.0      M    M
 11000    0.8  33.4   245   10    5   7.6   4.2   18.1  64.6     7.8      M    M
 10500    1.9  35.4   245    9    5   6.8   3.7   17.7  63.9     7.4      M    M
 10250    2.4  36.3   245    9    5   8.5   4.7   17.5  63.6     7.3      M    M
 10000    3.2  37.8   245    9    4  10.9   6.0   17.6  63.6     7.3      M    M
  9750    3.9  39.0   245    9    4   9.5   5.2   17.6  63.7     7.4      M    M
  9500    4.6  40.3   245    8    4   8.3   4.5   17.5  63.5     7.3      M    M
  9250    5.2  41.4   245    8    4   9.0   4.9   17.4  63.4     7.2      M    M
  9000    5.9  42.6   250    8    4   7.3   4.0   17.4  63.2     7.2      M    M
  8750    6.3  43.3   245    8    4   6.7   3.7   17.1  62.8     6.9      M    M
  8500    6.9  44.4   245    8    4   7.7   4.2   16.9  62.4     6.8      M    M
  8250    7.5  45.5   245    8    4   7.8   4.3   16.7  62.1     6.6      M    M
  8000    8.0  46.4   245    8    4   6.5   3.5   16.6  61.8     6.5      M    M
  7750    8.4  47.1   245    8    4   5.7   3.1   16.3  61.3     6.2      M    M
  7500    8.9  48.0   245    7    4   6.7   3.7   16.0  60.8     5.9      M    M
  7250    9.4  48.9   245    7    4   6.2   3.4   15.8  60.4     5.7      M    M
  7000    9.8  49.6   240    7    3   4.8   2.7   15.4  59.8     5.4      M    M
  6750   10.1  50.2   240    6    3   2.4   1.3   15.0  59.0     5.0      M    M
  6500   10.3  50.5   240    6    3   3.3   1.8   14.4  57.9     4.4      M    M
  6250   10.4  50.7   235    5    3  -2.2  -1.2   13.8  56.9     3.9      M    M
  6000    9.9  49.8   230    5    3  -8.7  -4.8   12.6  54.6     2.6      M    M
  5750    9.2  48.6   225    5    3 -11.5  -6.3   11.1  52.1     1.2      M    M
  5500    7.7  45.9   225    4    2 -33.7 -18.5    8.9  48.0    -1.0     88  0.4

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

           01/20/2018 at 0800 MST          |       01/20/2018 at 1100 MST
                                           |
CAPE...     0.0    LI...       +3.9        | CAPE...     0.0    LI...       +3.8
CINH...     0.0    K Index...  +7.9        | CINH...    -0.0    K Index...  +9.9
                                           |
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 -62.2 -80.0  250  18  9  -2.6  -1.4 | -61.4 -78.5  240  17  9  -1.5  -0.8
 45000 -66.1 -87.0  240  34 18  -2.7  -1.5 | -63.8 -82.8  240  36 18  -1.8  -1.0
 40000 -63.2 -81.8  230  40 21   2.2   1.2 | -63.0 -81.4  225  43 22   0.7   0.4
 38000 -60.3 -76.5  230  41 21   7.2   4.0 | -60.9 -77.6  225  44 23   7.1   3.9
 36000 -56.0 -68.8  230  40 21   7.2   4.0 | -56.6 -69.9  225  44 22   7.1   3.9
 34000 -51.6 -60.9  230  40 20   7.6   4.2 | -52.4 -62.3  225  43 22   7.6   4.1
 32000 -47.1 -52.8  230  38 20   7.5   4.1 | -47.3 -53.1  225  41 21   7.5   4.1
 30000 -42.0 -43.6  230  36 19   7.7   4.2 | -42.8 -45.0  225  39 20   7.5   4.1
 29000 -39.7 -39.5  230  35 18   7.7   4.2 | -40.5 -40.9  225  38 19   7.5   4.1
 28000 -37.4 -35.3  230  35 18   7.7   4.2 | -38.3 -36.9  225  37 19   7.6   4.1
 27000 -35.1 -31.2  230  34 17   7.6   4.2 | -36.0 -32.8  225  36 19   7.6   4.2
 26000 -32.9 -27.2  230  33 17   7.5   4.1 | -33.7 -28.7  225  35 18   7.6   4.2
 25000 -30.6 -23.1  230  33 17   7.5   4.1 | -31.5 -24.7  225  34 18   7.6   4.2
 24000 -28.4 -19.1  230  32 16   7.5   4.1 | -29.2 -20.6  225  33 17   7.6   4.2
 23000 -26.2 -15.2  235  31 16   7.5   4.1 | -26.9 -16.4  225  32 16   7.8   4.3
 22000 -23.9 -11.0  235  30 16   7.5   4.1 | -24.5 -12.1  225  31 16   7.8   4.3
 21000 -21.7  -7.1  235  29 15   7.6   4.2 | -22.2  -8.0  225  30 15   7.8   4.3
 20000 -19.4  -2.9  235  27 14   7.6   4.2 | -19.9  -3.8  225  28 14   7.8   4.3
 19500 -18.3  -0.9  235  27 14   7.6   4.2 | -18.7  -1.7  225  27 14   7.8   4.3
 19000 -17.1   1.2  235  26 13   7.6   4.2 | -17.6   0.3  225  26 13   7.8   4.3
 18500 -16.0   3.2  235  25 13   7.6   4.2 | -16.4   2.5  225  25 13   7.7   4.2
 18000 -14.9   5.2  235  24 12   7.4   4.1 | -15.3   4.5  225  25 13   7.4   4.1
 17500 -13.8   7.2  235  23 12   7.5   4.1 | -13.6   7.5  225  24 12   7.4   4.0
 17000 -12.7   9.1  235  22 11   7.2   3.9 | -12.6   9.3  225  23 12   6.9   3.8
 16500 -11.1  12.0  235  20 11   7.1   3.9 | -11.6  11.1  230  23 12   7.0   3.8
 16000 -10.0  14.0  235  20 10   7.2   3.9 | -10.5  13.1  230  22 11   6.9   3.8
 15500  -9.0  15.8  235  19 10   7.2   4.0 |  -9.5  14.9  230  21 11   6.9   3.8
 15000  -7.9  17.8  240  19 10   6.8   3.7 |  -8.5  16.7  230  20 10   6.9   3.8
 14500  -7.0  19.4  240  18  9   6.6   3.6 |  -7.5  18.5  235  19 10   6.9   3.8
 14000  -6.0  21.2  240  17  9   6.8   3.7 |  -6.5  20.3  235  18  9   6.9   3.8
 13500  -5.0  23.0  240  16  8   7.0   3.8 |  -5.5  22.1  235  17  9   6.7   3.7
 13000  -4.0  24.8  240  15  7   7.0   3.8 |  -4.5  23.9  235  16  8   6.7   3.7
 12500  -2.9  26.8  240  13  7   7.0   3.8 |  -3.5  25.7  235  14  7   6.6   3.6
 12000  -1.9  28.6  240  12  6   7.1   3.9 |  -2.6  27.3  235  12  6   6.7   3.7
 11500  -0.8  30.6  240  11  6   7.9   4.3 |  -1.5  29.3  235  11  6   7.2   3.9
 11000   0.4  32.7  240  10  5   7.7   4.2 |  -0.5  31.1  235   9  5   7.1   3.9
 10500   1.4  34.5  240  10  5   6.3   3.4 |   0.5  32.9  230   8  4   5.8   3.2
 10250   1.9  35.4  240   9  5   7.3   4.0 |   0.9  33.6  230   7  4   6.4   3.5
 10000   2.5  36.5  245   9  5   9.2   5.0 |   1.4  34.5  225   7  3   8.2   4.5
  9750   3.2  37.8  245   9  4   8.3   4.6 |   2.1  35.8  225   6  3   7.9   4.3
  9500   3.7  38.7  245   8  4   7.1   3.9 |   2.6  36.7  225   6  3   6.6   3.6
  9250   4.3  39.7  245   8  4   7.8   4.3 |   3.1  37.6  225   5  3   7.5   4.1
  9000   4.8  40.6  245   7  4   6.2   3.4 |   3.6  38.5  220   4  2   5.4   3.0
  8750   5.2  41.4  245   7  4   5.8   3.2 |   4.0  39.2  230   4  2   4.3   2.4
  8500   5.7  42.3  245   7  3   6.9   3.8 |   4.3  39.7  235   3  2   5.3   2.9
  8250   6.2  43.2  245   6  3   6.8   3.7 |   4.7  40.5  235   3  1   5.2   2.8
  8000   6.7  44.1  245   6  3   6.0   3.3 |   5.1  41.2  235   2  1   4.8   2.6
  7750   7.1  44.8  250   5  3   5.1   2.8 |   5.4  41.7  225   1  0   3.6   2.0
  7500   7.5  45.5  250   5  2   5.4   3.0 |   5.7  42.3  000   0  0   3.3   1.8
  7250   7.9  46.2  250   4  2   5.1   2.8 |   5.9  42.6  055   1  0   3.1   1.7
  7000   8.2  46.8  255   4  2   3.7   2.0 |   6.1  43.0  050   1  1   0.8   0.4
  6750   8.4  47.1  260   3  2   1.7   1.0 |   6.1  43.0  055   2  1   1.9   1.0
  6500   8.5  47.3  260   3  1   2.4   1.3 |   6.3  43.3  055   3  1   4.0   2.2
  6250   8.7  47.7  255   3  1  -1.3  -0.7 |   6.6  43.9  050   3  2   3.5   1.9
  6000   8.3  46.9  250   3  1  -5.7  -3.1 |   6.9  44.4  050   3  2   3.0   1.6
  5750   7.9  46.2  240   3  1  -7.1  -3.9 |   7.1  44.8  050   3  2   4.9   2.7
  5500   6.8  44.2  235   3  1 -27.0 -14.8 |   7.7  45.9  050   3  1  13.3   7.3

           01/20/2018 at 1400 MST          |       01/20/2018 at 1700 MST
                                           |
CAPE...     0.0    LI...       +3.6        | CAPE...     0.0    LI...       +1.6
CINH...    -0.0    K Index... +14.0        | CINH...    -0.1    K Index... +18.5
                                           |
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 -60.5 -76.9  240  18  9   0.2   0.1 | -59.6 -75.3  235  17  9   1.4   0.8
 45000 -60.1 -76.2  240  34 18   0.4   0.2 | -57.4 -71.3  235  32 16   1.8   1.0
 40000 -61.8 -79.2  225  43 22  -1.2  -0.7 | -60.2 -76.4  225  42 22  -2.1  -1.2
 38000 -60.6 -77.1  220  45 23   7.0   3.8 | -59.7 -75.5  220  46 23   5.8   3.2
 36000 -56.4 -69.5  220  44 23   6.9   3.8 | -56.3 -69.3  220  46 24   5.8   3.2
 34000 -51.7 -61.1  220  44 23   7.7   4.2 | -52.2 -62.0  215  47 24   7.8   4.3
 32000 -47.1 -52.8  220  43 22   7.6   4.2 | -47.7 -53.9  215  46 24   7.6   4.2
 30000 -42.6 -44.7  220  41 21   7.2   3.9 | -43.1 -45.6  220  45 23   7.0   3.8
 29000 -40.4 -40.7  220  40 21   7.3   4.0 | -41.0 -41.8  220  44 23   7.1   3.9
 28000 -38.2 -36.8  220  39 20   7.3   4.0 | -38.9 -38.0  220  43 22   7.1   3.9
 27000 -36.0 -32.8  225  39 20   7.3   4.0 | -36.8 -34.2  220  41 21   7.1   3.9
 26000 -33.8 -28.8  225  37 19   7.4   4.1 | -34.7 -30.5  220  40 20   7.0   3.8
 25000 -31.6 -24.9  225  36 19   7.4   4.1 | -32.6 -26.7  220  38 20   7.0   3.8
 24000 -29.4 -20.9  225  35 18   7.4   4.0 | -30.5 -22.9  220  37 19   7.0   3.8
 23000 -27.1 -16.8  225  34 17   7.7   4.2 | -28.3 -18.9  220  35 18   7.4   4.1
 22000 -24.8 -12.6  225  32 16   7.7   4.2 | -26.1 -15.0  220  33 17   7.4   4.1
 21000 -22.5  -8.5  220  30 16   7.7   4.2 | -23.9 -11.0  220  32 16   7.4   4.1
 20000 -20.3  -4.5  225  29 15   7.5   4.1 | -21.8  -7.2  220  30 15   7.1   3.9
 19500 -19.2  -2.6  225  29 15   7.5   4.1 | -20.7  -5.3  220  29 15   7.1   3.9
 19000 -18.1  -0.6  225  28 14   7.5   4.1 | -19.7  -3.5  220  28 15   7.1   3.9
 18500 -16.4   2.5  225  27 14   7.3   4.0 | -18.1  -0.6  225  27 14   7.0   3.8
 18000 -15.4   4.3  225  27 14   7.1   3.9 | -17.1   1.2  225  26 13   6.8   3.7
 17500 -14.3   6.3  225  27 14   7.1   3.9 | -16.1   3.0  225  25 13   6.8   3.7
 17000 -13.3   8.1  230  27 14   6.2   3.4 | -15.1   4.8  225  23 12   7.1   3.9
 16500 -12.4   9.7  230  26 13   6.3   3.4 | -14.0   6.8  225  22 11   7.1   3.9
 16000 -11.5  11.3  230  25 13   6.2   3.4 | -13.0   8.6  225  21 11   7.5   4.1
 15500 -10.6  12.9  230  23 12   6.2   3.4 | -11.9  10.6  225  20 10   7.7   4.2
 15000  -9.7  14.5  230  22 11   6.5   3.6 | -10.7  12.7  225  19 10   7.9   4.3
 14500  -8.7  16.3  230  20 10   7.1   3.9 |  -9.5  14.9  225  17  9   8.2   4.5
 14000  -7.6  18.3  230  19 10   7.1   3.9 |  -8.3  17.1  220  16  8   8.2   4.5
 13500  -6.6  20.1  230  17  9   7.4   4.0 |  -7.1  19.2  220  15  8   8.5   4.6
 13000  -5.5  22.1  230  16  8   7.4   4.0 |  -5.9  21.4  215  14  7   8.5   4.6
 12500  -4.4  24.1  225  14  7   7.4   4.1 |  -4.6  23.7  210  13  7   8.1   4.4
 12000  -3.3  26.1  225  13  7   7.4   4.1 |  -3.4  25.9  205  13  7   8.1   4.4
 11500  -2.2  28.0  220  12  6   7.7   4.2 |  -2.2  28.0  200  12  6   8.3   4.6
 11000  -1.0  30.2  215  11  6   7.8   4.3 |  -1.0  30.2  195  11  6   8.5   4.7
 10500  -0.0  32.0  210  10  5   6.1   3.4 |   0.1  32.2  190  10  5   6.1   3.3
 10250   0.5  32.9  205  10  5   6.6   3.6 |   0.6  33.1  190   9  5   6.1   3.4
 10000   1.0  33.8  205   9  5   8.6   4.7 |   1.1  34.0  185   8  4   7.4   4.0
  9750   1.7  35.1  205   8  4   7.9   4.3 |   1.6  34.9  180   7  4   5.3   2.9
  9500   2.1  35.8  200   7  4   6.0   3.3 |   1.8  35.2  175   6  3   2.7   1.5
  9250   2.6  36.7  200   6  3   7.0   3.8 |   2.1  35.8  165   6  3   3.5   1.9
  9000   3.1  37.6  195   6  3   4.7   2.6 |   2.3  36.1  155   5  3   3.0   1.6
  8750   3.3  37.9  195   5  2   3.2   1.8 |   2.5  36.5  150   5  2   0.8   0.4
  8500   3.6  38.5  190   4  2   4.0   2.2 |   2.4  36.3  140   4  2  -0.6  -0.3
  8250   3.9  39.0  180   3  1   4.4   2.4 |   2.4  36.3  130   4  2  -0.0  -0.0
  8000   4.2  39.6  160   2  1   2.0   1.1 |   2.4  36.3  115   3  2  -0.8  -0.4
  7750   4.2  39.6  130   2  1   0.1   0.1 |   2.3  36.1  100   3  2  -1.0  -0.5
  7500   4.3  39.7  100   2  1   1.5   0.8 |   2.3  36.1  085   4  2  -0.3  -0.2
  7250   4.4  39.9  080   3  1   1.0   0.5 |   2.2  36.0  070   4  2  -1.0  -0.6
  7000   4.5  40.1  065   4  2   2.7   1.5 |   2.2  36.0  060   4  2   2.0   1.1
  6750   4.8  40.6  060   4  2   7.6   4.2 |   2.6  36.7  055   5  2   7.6   4.2
  6500   5.5  41.9  055   4  2   9.8   5.4 |   3.2  37.8  050   5  2   8.9   4.9
  6250   6.2  43.2  050   4  2   9.3   5.1 |   3.8  38.8  045   5  3   8.5   4.7
  6000   6.9  44.4  050   4  2   9.6   5.2 |   4.5  40.1  040   5  3   8.4   4.6
  5750   7.6  45.7  050   4  2   9.4   5.2 |   5.1  41.2  040   5  3   8.8   4.8
  5500   8.4  47.1  045   4  2  13.7   7.5 |   5.8  42.4  040   4  2   8.5   4.6
________________________________________________________________________________

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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