Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 171327
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0626 MST Friday, November 17, 2017

This forecast is for Friday, November 17, 2017:

If the trigger temperature of 67.4 F/19.7 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 231 ft/min (1.2 m/s)
   Maximum height of thermals.................. 8742 ft MSL (3405 ft AGL)

Forecast maximum temperature................... 66.0 F/19.3 C
Time of trigger temperature.................... 1415 MST
Time of overdevelopment........................ 1600 MST
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6133 ft MSL (796 ft AGL)
Thermal soaring outlook for Saturday 11/18..... Fair

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1700 MST)......... Improving
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 39337 ft MSL (34000 ft AGL)
Wave soaring outlook for Saturday 11/18........ Excellent

Remarks...

Sunrise/Sunset.................... 06:46:59 / 16:42:04 MST
Total possible sunshine........... 9 hr 55 min 5 sec (595 min 5 sec)
Altitude of sun at 11:44:31 MST... 30.96 degrees

Upper air data from numerical model forecast valid on 11/17/2017 at 0500 MST

Freezing level.................. 12851 ft MSL (7514 ft AGL)
Convective condensation level... 16844 ft MSL (11507 ft AGL)
Lifted condensation level....... 14171 ft MSL (8834 ft AGL)
Lifted index.................... +4.0
K index......................... +11.7

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  -67.5 -89.5   255   43   22   4.9   2.7      M     M       M      M    M
 45000  -60.4 -76.7   260   47   24   2.4   1.3      M     M       M      M    M
 40000  -56.5 -69.7   265   59   30   2.6   1.4      M     M       M      M    M
 38000  -54.0 -65.2   265   61   31   4.7   2.6      M     M       M      M    M
 36000  -50.9 -59.6   265   62   32   4.7   2.6      M     M       M      M    M
 34000  -47.4 -53.3   270   61   32   7.4   4.1      M     M       M      M    M
 32000  -43.0 -45.4   265   57   29   7.4   4.0      M     M       M      M    M
 30000  -38.5 -37.3   265   52   27   7.6   4.2   37.2  99.0    13.8      M    M
 29000  -36.2 -33.2   265   49   25   7.6   4.1   36.3  97.3    13.3      M    M
 28000  -34.0 -29.2   265   47   24   7.6   4.1   35.5  95.9    12.8      M    M
 27000  -31.7 -25.1   265   44   23   7.7   4.2   34.8  94.6    12.4      M    M
 26000  -29.4 -20.9   265   41   21   7.7   4.2   33.9  92.9    11.8      M    M
 25000  -27.1 -16.8   265   39   20   7.7   4.2   33.1  91.6    11.3      M    M
 24000  -24.8 -12.6   265   37   19   7.6   4.2   32.4  90.4    10.9      M    M
 23000  -22.6  -8.7   265   36   18   7.6   4.2   31.5  88.8    10.3      M    M
 22000  -20.3  -4.5   265   34   18   7.6   4.2   30.8  87.4     9.7      M    M
 21000  -18.0  -0.4   265   33   17   7.5   4.1   30.1  86.1     9.2      M    M
 20000  -15.8   3.6   270   32   17   7.5   4.1   29.2  84.5     8.6      M    M
 19500  -14.2   6.4   270   31   16   7.5   4.1   28.6  83.5     8.1      M    M
 19000  -13.0   8.6   270   31   16   7.5   4.1   28.2  82.8     7.9      M    M
 18500  -12.0  10.4   270   30   16   7.0   3.9   27.8  82.1     7.5      M    M
 18000  -10.9  12.4   270   30   15   7.1   3.9   27.4  81.3     7.2      M    M
 17500   -9.9  14.2   270   29   15   7.0   3.9   26.9  80.5     6.8      M    M
 17000   -8.8  16.2   270   29   15   7.0   3.8   26.4  79.6     6.4      M    M
 16500   -7.8  18.0   270   28   15   7.0   3.8   26.0  78.8     6.0      M    M
 16000   -6.7  19.9   270   28   15   7.1   3.9   25.5  77.9     5.6      M    M
 15500   -5.7  21.7   265   28   14   7.1   3.9   25.1  77.1     5.2      M    M
 15000   -4.6  23.7   265   28   14   7.3   4.0   24.6  76.4     4.9      M    M
 14500   -3.5  25.7   265   27   14   7.4   4.1   24.3  75.7     4.5      M    M
 14000   -2.4  27.7   265   27   14   7.4   4.0   23.9  75.0     4.2      M    M
 13500   -1.3  29.7   265   28   14   7.3   4.0   23.5  74.2     3.8      M    M
 13000   -0.3  31.5   265   28   15   7.3   4.0   23.1  73.5     3.5      M    M
 12500    0.8  33.4   265   29   15   7.1   3.9   22.6  72.8     3.1      M    M
 12000    1.8  35.2   265   29   15   7.1   3.9   22.2  72.0     2.7      M    M
 11500    2.9  37.2   265   27   14   7.5   4.1   21.8  71.3     2.3      M    M
 11000    4.0  39.2   260   25   13   7.4   4.1   21.5  70.6     2.0      M    M
 10500    5.1  41.2   260   24   12   6.9   3.8   21.1  69.9     1.6      M    M
 10250    5.6  42.1   260   23   12   7.5   4.1   20.8  69.5     1.4      M    M
 10000    6.2  43.2   260   23   12   8.2   4.5   20.7  69.3     1.2      M    M
  9750    6.7  44.1   260   23   12   7.7   4.2   20.6  69.0     1.1      M    M
  9500    7.3  45.1   260   23   12   7.4   4.1   20.4  68.7     0.9      M    M
  9250    7.8  46.0   255   24   12   7.6   4.2   20.2  68.4     0.7      M    M
  9000    8.3  46.9   255   24   12   5.3   2.9   20.0  68.0     0.5      M    M
  8750    8.7  47.7   255   23   12   5.0   2.8   19.6  67.2     0.0      M    M
  8500    9.1  48.4   255   24   12   6.6   3.6   19.3  66.7    -0.2    214  1.1
  8250    9.6  49.3   255   24   12   6.4   3.5   19.0  66.3    -0.5    193  1.0
  8000   10.0  50.0   255   24   12   5.7   3.1   18.8  65.8    -0.8    172  0.9
  7750   10.4  50.7   255   23   12   5.8   3.2   18.4  65.2    -1.1    153  0.8
  7500   10.9  51.6   255   22   11   6.6   3.6   18.2  64.7    -1.4    131  0.7
  7250   11.3  52.3   250   21   11   6.4   3.5   17.9  64.3    -1.7    110  0.6
  7000   11.8  53.2   250   20   10   6.5   3.5   17.7  63.8    -1.9     88  0.4
  6750   12.3  54.1   250   19   10   6.6   3.6   17.4  63.4    -2.2     67  0.3
  6500   12.8  55.0   245   18    9   7.5   4.1   17.2  63.0    -2.4     44  0.2
  6250   13.3  55.9   245   16    8   5.2   2.9   17.0  62.6    -2.6     20  0.1
  6000   13.6  56.5   240   15    8   0.9   0.5   16.5  61.7    -3.1      7  0.0
  5750   13.6  56.5   240   13    7   0.2   0.1   15.8  60.4    -3.8      M    M
  5500   13.5  56.3   235   10    5  -4.5  -2.5   15.0  58.9    -4.7      M    M

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

           11/17/2017 at 0800 MST          |       11/17/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +2.8        | CAPE...    +0.1    LI...       +1.4
CINH...    -0.2    K Index... +13.4        | CINH...    -8.8    K Index... +19.5
                                           |
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 -66.5 -87.7  255  44 23   4.2   2.3 | -65.0 -85.0  255  43 22   4.2   2.3
 45000 -60.3 -76.5  260  47 24   2.4   1.3 | -58.8 -73.8  255  48 25   2.3   1.3
 40000 -56.4 -69.5  260  58 30   2.6   1.4 | -55.0 -67.0  260  61 32   2.5   1.4
 38000 -53.9 -65.0  265  61 31   5.2   2.9 | -52.8 -63.0  260  66 34   4.7   2.6
 36000 -50.7 -59.3  265  64 33   5.2   2.9 | -50.0 -58.0  260  70 36   4.7   2.6
 34000 -46.8 -52.2  265  64 33   7.1   3.9 | -46.5 -51.7  260  72 37   6.4   3.5
 32000 -42.5 -44.5  265  61 31   7.1   3.9 | -42.7 -44.9  260  68 35   6.4   3.5
 30000 -38.3 -36.9  265  56 29   6.8   3.7 | -38.9 -38.0  260  63 33   6.1   3.4
 29000 -36.3 -33.3  265  53 27   6.8   3.7 | -37.0 -34.6  260  60 31   6.1   3.4
 28000 -34.3 -29.7  265  49 25   6.8   3.7 | -35.2 -31.4  260  57 29   6.1   3.4
 27000 -32.2 -26.0  265  46 24   6.8   3.7 | -33.4 -28.1  260  54 28   6.1   3.3
 26000 -30.2 -22.4  265  44 22   6.8   3.7 | -31.6 -24.9  260  50 26   6.1   3.3
 25000 -28.2 -18.8  265  41 21   6.8   3.7 | -29.7 -21.5  260  47 24   6.1   3.3
 24000 -26.2 -15.2  265  38 20   7.0   3.8 | -27.9 -18.2  260  43 22   6.2   3.4
 23000 -23.9 -11.0  265  36 19   7.6   4.1 | -25.7 -14.3  260  40 21   7.6   4.2
 22000 -21.7  -7.1  265  35 18   7.6   4.2 | -23.5 -10.3  260  38 20   7.6   4.2
 21000 -19.4  -2.9  265  33 17   7.5   4.1 | -21.2  -6.2  260  36 18   7.7   4.2
 20000 -17.2   1.0  265  32 16   7.4   4.1 | -18.9  -2.0  265  34 18   7.8   4.3
 19500 -15.6   3.9  265  31 16   7.4   4.1 | -17.8  -0.0  265  33 17   7.8   4.3
 19000 -14.5   5.9  265  30 15   7.4   4.1 | -16.6   2.1  265  33 17   7.8   4.3
 18500 -13.4   7.9  265  29 15   7.4   4.1 | -14.9   5.2  265  32 16   7.6   4.2
 18000 -12.3   9.9  270  29 15   7.4   4.1 | -13.8   7.2  265  30 16   7.5   4.1
 17500 -11.2  11.8  270  28 14   7.4   4.1 | -12.7   9.1  260  29 15   7.5   4.1
 17000 -10.1  13.8  270  28 14   7.3   4.0 | -11.6  11.1  260  28 14   7.5   4.1
 16500  -9.0  15.8  270  28 14   7.3   4.0 | -10.5  13.1  260  27 14   7.5   4.1
 16000  -7.9  17.8  270  27 14   7.7   4.2 |  -9.4  15.1  260  26 13   7.5   4.1
 15500  -6.8  19.8  270  27 14   7.7   4.2 |  -8.2  17.2  260  25 13   7.5   4.1
 15000  -5.6  21.9  270  26 14   7.6   4.2 |  -7.1  19.2  260  23 12   7.1   3.9
 14500  -4.5  23.9  270  26 13   7.6   4.1 |  -6.1  21.0  260  22 11   6.9   3.8
 14000  -3.4  25.9  270  26 13   7.5   4.1 |  -5.1  22.8  260  21 11   7.1   3.9
 13500  -2.3  27.9  270  26 13   7.5   4.1 |  -4.0  24.8  260  21 11   7.6   4.2
 13000  -1.2  29.8  270  25 13   7.5   4.1 |  -2.9  26.8  260  21 11   7.5   4.1
 12500  -0.1  31.8  270  25 13   7.0   3.8 |  -1.8  28.8  260  20 10   7.1   3.9
 12000   0.9  33.6  270  24 12   7.0   3.8 |  -0.8  30.6  260  19 10   7.1   3.9
 11500   1.9  35.4  270  24 12   6.3   3.5 |   0.3  32.5  260  18  9   7.5   4.1
 11000   2.8  37.0  265  24 12   6.4   3.5 |   1.4  34.5  260  17  9   7.5   4.1
 10500   3.7  38.7  265  24 12   6.2   3.4 |   2.4  36.3  260  16  8   6.4   3.5
 10250   4.2  39.6  265  24 12   6.8   3.7 |   2.9  37.2  260  16  8   7.6   4.2
 10000   4.7  40.5  265  24 12   7.6   4.2 |   3.6  38.5  260  16  8   9.2   5.0
  9750   5.3  41.5  265  24 12   7.3   4.0 |   4.2  39.6  255  15  8   8.4   4.6
  9500   5.8  42.4  265  23 12   6.9   3.8 |   4.8  40.6  255  15  8   7.6   4.2
  9250   6.3  43.3  265  23 12   7.2   4.0 |   5.4  41.7  255  15  8   7.9   4.4
  9000   6.8  44.2  265  23 12   5.9   3.2 |   5.9  42.6  255  15  8   6.6   3.6
  8750   7.2  45.0  265  23 12   5.8   3.2 |   6.4  43.5  255  15  7   7.2   3.9
  8500   7.7  45.9  265  23 12   6.9   3.8 |   7.0  44.6  255  14  7   8.7   4.8
  8250   8.1  46.6  260  22 11   6.6   3.6 |   7.6  45.7  255  13  7   8.2   4.5
  8000   8.6  47.5  260  22 11   6.8   3.7 |   8.2  46.8  255  12  6   8.8   4.8
  7750   9.1  48.4  260  21 11   7.1   3.9 |   8.9  48.0  255  12  6   9.6   5.3
  7500   9.7  49.5  260  20 10   7.1   3.9 |   9.7  49.5  255  11  6   9.9   5.4
  7250  10.2  50.4  255  19 10   7.1   3.9 |  10.4  50.7  255  11  6   9.9   5.4
  7000  10.7  51.3  255  18  9   7.3   4.0 |  11.1  52.0  255  11  5   8.9   4.9
  6750  11.2  52.2  255  17  9   7.1   3.9 |  11.8  53.2  255  10  5   9.5   5.2
  6500  11.8  53.2  250  15  8   7.3   4.0 |  12.5  54.5  255  10  5  10.8   5.9
  6250  12.3  54.1  250  14  7   5.8   3.2 |  13.3  55.9  255   9  5  10.3   5.7
  6000  12.6  54.7  245  12  6   2.4   1.3 |  14.1  57.4  255   9  5  10.7   5.9
  5750  12.7  54.9  240  10  5   1.8   1.0 |  14.9  58.8  255   8  4   9.4   5.1
  5500  12.8  55.0  240   8  4   0.4   0.2 |  15.6  60.1  255   7  4  11.6   6.4

           11/17/2017 at 1400 MST          |       11/17/2017 at 1700 MST
                                           |
CAPE...   +23.1    LI...       +0.4        | CAPE...    +9.8    LI...       -0.3
CINH...   -47.4    K Index... +17.5        | CINH...   -59.3    K Index... +19.2
                                           |
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 -64.8 -84.6  255  45 23   4.0   2.2 | -64.3 -83.7  260  41 21   4.1   2.2
 45000 -58.6 -73.5  260  49 25   2.9   1.6 | -57.9 -72.2  260  47 24   3.2   1.8
 40000 -54.2 -65.6  260  60 31   3.0   1.6 | -53.2 -63.8  260  57 30   3.2   1.8
 38000 -52.0 -61.6  260  65 33   4.2   2.3 | -51.0 -59.8  260  61 32   3.9   2.2
 36000 -49.5 -57.1  260  69 36   4.2   2.3 | -48.6 -55.5  260  65 33   3.9   2.2
 34000 -46.8 -52.2  260  73 37   6.1   3.4 | -46.2 -51.2  260  68 35   4.7   2.6
 32000 -42.8 -45.0  260  69 36   5.9   3.3 | -43.1 -45.6  260  65 33   4.7   2.6
 30000 -39.4 -38.9  260  65 34   5.4   3.0 | -40.3 -40.5  265  61 31   4.6   2.5
 29000 -37.7 -35.9  260  61 32   5.4   3.0 | -38.9 -38.0  265  58 30   4.6   2.6
 28000 -36.1 -33.0  260  58 30   5.4   3.0 | -37.5 -35.5  265  54 28   4.7   2.6
 27000 -34.5 -30.1  260  54 28   5.6   3.1 | -36.1 -33.0  265  51 26   4.7   2.6
 26000 -32.7 -26.9  260  49 25   6.0   3.3 | -34.3 -29.7  265  48 25   6.3   3.5
 25000 -30.9 -23.6  260  45 23   6.1   3.3 | -32.4 -26.3  265  46 23   6.3   3.5
 24000 -29.1 -20.4  260  41 21   6.0   3.3 | -30.5 -22.9  265  43 22   6.3   3.4
 23000 -27.1 -16.8  260  38 19   7.0   3.8 | -28.5 -19.3  265  41 21   7.3   4.0
 22000 -25.0 -13.0  260  36 18   7.0   3.8 | -26.3 -15.3  265  38 20   7.3   4.0
 21000 -22.9  -9.2  260  33 17   7.3   4.0 | -24.1 -11.4  265  36 19   7.3   4.0
 20000 -20.6  -5.1  260  32 16   7.9   4.4 | -21.8  -7.2  265  35 18   7.9   4.4
 19500 -19.4  -2.9  265  31 16   8.0   4.4 | -20.6  -5.1  265  34 17   7.9   4.4
 19000 -18.2  -0.8  265  30 16   8.0   4.4 | -19.5  -3.1  265  33 17   7.9   4.4
 18500 -17.1   1.2  265  30 15   8.0   4.4 | -18.3  -0.9  265  32 16   7.9   4.4
 18000 -15.9   3.4  265  28 15   8.3   4.6 | -17.1   1.2  265  31 16   8.2   4.5
 17500 -14.0   6.8  260  26 14   8.3   4.5 | -15.3   4.5  265  31 16   8.2   4.5
 17000 -12.8   9.0  260  25 13   7.8   4.3 | -14.1   6.6  265  31 16   8.0   4.4
 16500 -11.7  10.9  260  24 12   7.9   4.3 | -12.9   8.8  265  30 15   8.0   4.4
 16000 -10.5  13.1  260  23 12   7.8   4.3 | -11.7  10.9  265  29 15   8.2   4.5
 15500  -9.4  15.1  260  23 12   7.8   4.3 | -10.5  13.1  265  28 14   8.3   4.5
 15000  -8.2  17.2  265  22 11   7.8   4.3 |  -9.3  15.3  260  27 14   8.2   4.5
 14500  -7.1  19.2  265  22 11   7.8   4.3 |  -8.1  17.4  260  26 13   7.9   4.3
 14000  -5.9  21.4  265  22 11   7.9   4.3 |  -7.0  19.4  260  25 13   7.9   4.3
 13500  -4.7  23.5  265  22 11   8.1   4.4 |  -5.8  21.6  260  24 12   7.7   4.2
 13000  -3.5  25.7  265  22 11   8.1   4.4 |  -4.7  23.5  260  22 11   7.7   4.2
 12500  -2.3  27.9  265  22 11   8.0   4.4 |  -3.5  25.7  260  21 11   7.8   4.3
 12000  -1.1  30.0  265  22 11   8.0   4.4 |  -2.4  27.7  260  20 10   7.7   4.2
 11500   0.0  32.0  265  22 11   7.8   4.3 |  -1.2  29.8  260  19 10   8.7   4.8
 11000   1.2  34.2  265  21 11   7.9   4.3 |   0.0  32.0  260  19 10   8.7   4.8
 10500   2.2  36.0  265  21 11   6.4   3.5 |   1.2  34.2  260  18  9   6.9   3.8
 10250   2.7  36.9  265  21 11   7.6   4.2 |   1.7  35.1  260  17  9   8.1   4.5
 10000   3.3  37.9  265  20 10   9.3   5.1 |   2.4  36.3  260  17  9   9.9   5.4
  9750   4.0  39.2  265  19 10   8.9   4.9 |   3.1  37.6  255  16  8   9.8   5.4
  9500   4.6  40.3  265  18 10   8.5   4.7 |   3.9  39.0  255  15  8   9.4   5.2
  9250   5.3  41.5  265  18  9   8.7   4.8 |   4.6  40.3  255  14  7   9.8   5.4
  9000   5.9  42.6  265  17  9   7.5   4.1 |   5.2  41.4  255  13  7   7.2   3.9
  8750   6.4  43.5  265  16  8   7.9   4.4 |   5.7  42.3  250  13  7   7.4   4.1
  8500   7.1  44.8  265  16  8   9.2   5.1 |   6.4  43.5  250  13  6   9.9   5.4
  8250   7.7  45.9  265  15  8   8.7   4.7 |   7.1  44.8  250  12  6   9.4   5.2
  8000   8.4  47.1  265  14  7   9.7   5.3 |   7.8  46.0  250  11  6   8.8   4.8
  7750   9.1  48.4  265  14  7  10.2   5.6 |   8.4  47.1  245  11  6   8.7   4.8
  7500   9.9  49.8  265  13  7   9.5   5.2 |   9.1  48.4  245  10  5   9.4   5.2
  7250  10.6  51.1  265  13  7   9.9   5.4 |   9.8  49.6  245  10  5   9.1   5.0
  7000  11.3  52.3  265  12  6   9.0   4.9 |  10.5  50.9  245   9  5   9.6   5.3
  6750  12.0  53.6  265  12  6   9.5   5.2 |  11.2  52.2  240   9  5   9.4   5.1
  6500  12.7  54.9  265  11  6  10.6   5.8 |  11.9  53.4  240   8  4   8.9   4.9
  6250  13.5  56.3  265  11  6  10.4   5.7 |  12.5  54.5  240   8  4   8.8   4.9
  6000  14.3  57.7  265  10  5  10.0   5.5 |  13.2  55.8  240   7  4   9.3   5.1
  5750  15.1  59.2  270  10  5  12.7   7.0 |  13.8  56.8  235   6  3   4.6   2.5
  5500  16.2  61.2  270   8  4  18.5  10.2 |  13.7  56.7  235   4  2  -4.9  -2.7
________________________________________________________________________________

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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