Soaring Guidance
Issued by NWS Denver/Boulder, CO

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467
UXUS97 KBOU 170042
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1742 MST Thursday, November 16, 2017

This forecast is for Friday, November 17, 2017:

If the trigger temperature of 66.3 F/19.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8179 ft MSL (2839 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 5919 ft MSL (579 ft AGL)
Thermal soaring outlook for Saturday 11/18..... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Becoming fair
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 35140 ft MSL (29800 ft AGL)
Wave soaring outlook for Saturday 11/18........ Fair

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.................. 12808 ft MSL (7468 ft AGL)
Convective condensation level... 16275 ft MSL (10935 ft AGL)
Lifted condensation level....... 13502 ft MSL (8162 ft AGL)
Lifted index.................... +4.8
K index......................... +11.6

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -66.8 -88.2   255   44   22   4.4   2.4      M     M       M      M    M
 45000  -60.4 -76.7   260   46   24   1.5   0.9      M     M       M      M    M
 40000  -57.7 -71.9   260   56   29   1.8   1.0      M     M       M      M    M
 38000  -55.0 -67.0   260   59   31   5.8   3.2      M     M       M      M    M
 36000  -51.1 -60.0   265   62   32   5.8   3.2      M     M       M      M    M
 34000  -47.3 -53.1   265   62   32   6.9   3.8      M     M       M      M    M
 32000  -43.2 -45.8   265   58   30   6.9   3.8      M     M       M      M    M
 30000  -38.8 -37.8   265   53   27   8.0   4.4   36.7  98.1    14.3      M    M
 29000  -36.4 -33.5   260   49   25   8.0   4.4   36.0  96.8    13.9      M    M
 28000  -34.1 -29.4   260   46   24   8.0   4.4   35.4  95.7    13.6      M    M
 27000  -31.7 -25.1   260   43   22   7.9   4.4   34.8  94.6    13.3      M    M
 26000  -29.3 -20.7   255   39   20   7.9   4.4   34.0  93.2    12.8      M    M
 25000  -26.9 -16.4   255   35   18   7.9   4.4   33.3  92.0    12.4      M    M
 24000  -24.6 -12.3   255   31   16   7.9   4.3   32.8  91.0    12.1      M    M
 23000  -22.2  -8.0   260   32   16   7.8   4.3   32.0  89.5    11.5      M    M
 22000  -19.9  -3.8   260   32   17   7.8   4.3   31.3  88.3    11.1      M    M
 21000  -17.6   0.3   260   33   17   7.0   3.8   30.6  87.1    10.6      M    M
 20000  -15.6   3.9   265   31   16   6.8   3.7   29.5  85.0     9.8      M    M
 19500  -14.1   6.6   265   30   15   6.8   3.7   28.7  83.7     9.2      M    M
 19000  -13.1   8.4   265   29   15   6.8   3.8   28.2  82.8     8.8      M    M
 18500  -12.1  10.2   265   28   15   6.4   3.5   27.7  81.9     8.4      M    M
 18000  -11.1  12.0   265   28   14   6.5   3.5   27.1  80.9     7.9      M    M
 17500  -10.2  13.6   265   27   14   6.6   3.6   26.6  79.9     7.5      M    M
 17000   -9.1  15.6   265   27   14   6.8   3.7   26.1  78.9     7.1      M    M
 16500   -8.1  17.4   265   27   14   6.7   3.7   25.6  78.0     6.7      M    M
 16000   -7.1  19.2   265   27   14   7.9   4.3   25.2  77.3     6.3      M    M
 15500   -5.9  21.4   265   26   13   7.8   4.3   24.8  76.7     6.0      M    M
 15000   -4.7  23.5   265   26   13   7.6   4.2   24.5  76.1     5.8      M    M
 14500   -3.6  25.5   265   26   14   7.6   4.2   24.1  75.5     5.4      M    M
 14000   -2.5  27.5   265   27   14   7.4   4.1   23.8  74.8     5.1      M    M
 13500   -1.4  29.5   265   27   14   7.3   4.0   23.4  74.1     4.8      M    M
 13000   -0.4  31.3   260   26   14   7.3   4.0   23.0  73.4     4.4      M    M
 12500    0.7  33.3   260   25   13   7.2   3.9   22.6  72.6     4.0      M    M
 12000    1.8  35.2   255   23   12   7.2   4.0   22.2  71.9     3.7      M    M
 11500    2.8  37.0   255   22   11   7.2   4.0   21.8  71.2     3.3      M    M
 11000    3.9  39.0   255   22   11   7.1   3.9   21.4  70.5     2.9      M    M
 10500    4.8  40.6   255   23   12   5.7   3.1   20.8  69.5     2.4      M    M
 10250    5.3  41.5   255   24   12   6.9   3.8   20.5  69.0     2.1      M    M
 10000    5.8  42.4   255   24   13   8.1   4.4   20.4  68.7     1.9      M    M
  9750    6.4  43.5   255   24   13   6.7   3.7   20.2  68.4     1.8      M    M
  9500    6.8  44.2   255   25   13   6.0   3.3   19.9  67.9     1.5      M    M
  9250    7.2  45.0   255   25   13   6.1   3.4   19.6  67.4     1.2      M    M
  9000    7.7  45.9   260   25   13   7.4   4.0   19.4  66.9     0.9      M    M
  8750    8.3  46.9   255   24   12   6.9   3.8   19.2  66.6     0.8      M    M
  8500    8.7  47.7   255   23   12   5.7   3.1   18.9  66.1     0.4      M    M
  8250    9.1  48.4   255   23   12   5.7   3.1   18.6  65.5     0.1      M    M
  8000    9.5  49.1   255   22   11   6.9   3.8   18.3  65.0    -0.2    169  0.9
  7750   10.1  50.2   255   20   10   7.3   4.0   18.2  64.7    -0.3    145  0.7
  7500   10.6  51.1   255   19   10   6.3   3.4   17.9  64.2    -0.6    123  0.6
  7250   11.1  52.0   250   18    9   6.5   3.6   17.7  63.8    -0.8    102  0.5
  7000   11.6  52.9   250   17    9   7.7   4.2   17.5  63.4    -1.1     79  0.4
  6750   12.1  53.8   250   16    8   6.8   3.7   17.3  63.1    -1.2     55  0.3
  6500   12.6  54.7   245   15    8   5.9   3.3   17.0  62.6    -1.5     34  0.2
  6250   13.0  55.4   245   14    7   4.1   2.2   16.7  62.1    -1.8     14  0.1
  6000   13.1  55.6   240   12    6  -0.4  -0.2   16.1  60.9    -2.5      4  0.0
  5750   13.0  55.4   235   10    5  -1.1  -0.6   15.3  59.5    -3.3      M    M
  5500   12.8  55.0   230    8    4  -6.8  -3.7   14.3  57.7    -4.3      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...       +3.1        | CAPE...     0.0    LI...       +1.5
CINH...    -0.1    K Index... +15.2        | CINH...    -0.9    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 -66.2 -87.2  255  46 23   4.1   2.2 | -65.1 -85.2  255  45 23   4.1   2.2
 45000 -60.2 -76.4  260  50 26   2.2   1.2 | -59.1 -74.4  255  49 25   2.6   1.4
 40000 -56.7 -70.1  260  63 32   2.3   1.3 | -55.0 -67.0  260  62 32   2.7   1.5
 38000 -54.1 -65.4  260  65 33   5.4   2.9 | -52.7 -62.9  260  66 34   4.5   2.5
 36000 -50.9 -59.6  260  66 34   5.4   2.9 | -50.0 -58.0  260  69 35   4.5   2.5
 34000 -47.0 -52.6  260  65 33   6.8   3.7 | -46.6 -51.9  260  70 36   6.4   3.5
 32000 -42.9 -45.2  260  61 31   6.8   3.7 | -42.8 -45.0  260  66 34   6.4   3.5
 30000 -38.8 -37.8  260  57 29   7.0   3.8 | -38.9 -38.0  260  62 32   6.3   3.4
 29000 -36.7 -34.1  260  54 28   6.9   3.8 | -37.1 -34.8  260  59 31   6.2   3.4
 28000 -34.6 -30.3  260  51 26   7.0   3.8 | -35.2 -31.4  260  56 29   6.2   3.4
 27000 -32.6 -26.7  260  48 25   7.0   3.8 | -33.3 -27.9  260  53 27   6.3   3.4
 26000 -30.5 -22.9  260  45 23   7.0   3.8 | -31.5 -24.7  260  49 25   6.3   3.5
 25000 -28.4 -19.1  260  41 21   7.0   3.8 | -29.6 -21.3  260  45 23   6.3   3.5
 24000 -26.3 -15.3  260  38 20   7.2   4.0 | -27.7 -17.9  260  41 21   6.3   3.5
 23000 -24.0 -11.2  260  35 18   7.8   4.3 | -25.7 -14.3  260  38 20   6.9   3.8
 22000 -21.7  -7.1  260  32 16   7.8   4.3 | -23.7 -10.7  260  36 18   6.9   3.8
 21000 -19.4  -2.9  260  29 15   7.7   4.2 | -21.6  -6.9  260  33 17   7.0   3.9
 20000 -17.2   1.0  260  28 14   7.6   4.2 | -19.5  -3.1  260  31 16   7.2   4.0
 19500 -16.0   3.2  260  28 14   7.6   4.2 | -18.4  -1.1  260  29 15   7.2   4.0
 19000 -14.3   6.3  260  27 14   7.7   4.2 | -16.8   1.8  260  28 14   7.2   4.0
 18500 -13.3   8.1  265  27 14   6.8   3.7 | -15.7   3.7  260  26 14   7.7   4.2
 18000 -12.3   9.9  265  26 14   6.8   3.7 | -14.6   5.7  260  25 13   7.9   4.3
 17500 -11.3  11.7  265  26 13   6.8   3.7 | -13.4   7.9  260  24 12   7.9   4.3
 17000 -10.2  13.6  265  26 13   7.0   3.8 | -12.2  10.0  260  24 12   7.9   4.3
 16500  -9.2  15.4  265  26 13   6.9   3.8 | -11.0  12.2  265  23 12   7.9   4.3
 16000  -8.1  17.4  265  26 13   7.6   4.2 |  -9.9  14.2  265  23 12   7.8   4.3
 15500  -7.0  19.4  265  26 13   7.5   4.1 |  -8.7  16.3  265  24 12   7.7   4.3
 15000  -5.9  21.4  265  26 13   7.5   4.1 |  -7.6  18.3  265  24 12   7.3   4.0
 14500  -4.8  23.4  265  25 13   7.6   4.1 |  -6.6  20.1  265  23 12   7.0   3.8
 14000  -3.7  25.3  270  25 13   7.6   4.2 |  -5.5  22.1  265  23 12   6.9   3.8
 13500  -2.5  27.5  270  24 12   7.7   4.2 |  -4.5  23.9  265  22 11   6.9   3.8
 13000  -1.4  29.5  265  23 12   7.6   4.2 |  -3.5  25.7  270  21 11   7.0   3.8
 12500  -0.3  31.5  265  22 11   7.2   4.0 |  -2.4  27.7  270  20 10   7.6   4.2
 12000   0.8  33.4  265  20 10   7.2   3.9 |  -1.3  29.7  270  18  9   7.6   4.2
 11500   1.7  35.1  265  20 10   6.3   3.4 |  -0.2  31.6  270  17  9   7.2   3.9
 11000   2.7  36.9  265  21 11   6.3   3.5 |   0.9  33.6  270  18  9   7.2   3.9
 10500   3.5  38.3  270  21 11   5.6   3.1 |   1.9  35.4  270  18 10   6.5   3.6
 10250   4.0  39.2  270  21 11   6.4   3.5 |   2.4  36.3  270  18  9   7.1   3.9
 10000   4.5  40.1  270  21 11   7.6   4.2 |   2.9  37.2  270  18  9   8.0   4.4
  9750   5.0  41.0  265  21 11   7.1   3.9 |   3.5  38.3  270  18  9   8.1   4.4
  9500   5.5  41.9  265  21 11   6.4   3.5 |   4.1  39.4  270  17  9   8.0   4.4
  9250   6.0  42.8  265  21 11   7.2   3.9 |   4.7  40.5  270  17  9   8.1   4.4
  9000   6.5  43.7  265  21 11   4.7   2.6 |   5.3  41.5  270  16  8   7.5   4.1
  8750   6.7  44.1  265  20 10   4.2   2.3 |   5.8  42.4  270  15  8   7.9   4.4
  8500   7.2  45.0  265  20 10   6.2   3.4 |   6.4  43.5  265  15  8   8.7   4.8
  8250   7.6  45.7  265  19 10   5.6   3.1 |   7.1  44.8  265  14  7   8.6   4.7
  8000   8.0  46.4  260  19 10   6.0   3.3 |   7.7  45.9  265  13  7   8.2   4.5
  7750   8.4  47.1  260  18  9   6.3   3.4 |   8.3  46.9  265  13  7   8.6   4.7
  7500   8.9  48.0  260  17  9   6.3   3.5 |   9.0  48.2  265  12  6   9.3   5.1
  7250   9.4  48.9  260  16  8   6.3   3.4 |   9.7  49.5  265  11  6   9.2   5.0
  7000   9.8  49.6  255  14  7   6.7   3.7 |  10.3  50.5  265  10  5   8.2   4.5
  6750  10.3  50.5  255  14  7   6.3   3.5 |  10.9  51.6  265   9  5   9.0   4.9
  6500  10.8  51.4  250  12  6   6.2   3.4 |  11.7  53.1  265   9  4  10.3   5.7
  6250  11.2  52.2  250  11  6   4.9   2.7 |  12.4  54.3  265   8  4  10.0   5.5
  6000  11.5  52.7  245   9  5   2.4   1.3 |  13.2  55.8  265   7  4  10.5   5.8
  5750  11.6  52.9  235   8  4   1.7   0.9 |  13.9  57.0  265   7  4   9.5   5.2
  5500  11.6  52.9  230   6  3  -2.8  -1.5 |  14.7  58.5  265   6  3  11.5   6.3

           11/17/2017 at 1400 MST          |       11/17/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +1.0        | CAPE...   +53.3    LI...       -1.1
CINH...    -0.1    K Index... +18.2        | CINH...   -29.1    K Index... +23.4
                                           |
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 -64.8 -84.6  255  43 22   4.4   2.4 | -63.7 -82.7  260  37 19   4.7   2.6
 45000 -57.9 -72.2  255  47 24   2.5   1.4 | -56.5 -69.7  260  44 23   3.1   1.7
 40000 -54.2 -65.6  260  61 32   2.5   1.4 | -52.2 -62.0  260  57 29   2.9   1.6
 38000 -52.2 -62.0  260  66 34   3.9   2.1 | -50.4 -58.7  260  61 32   2.9   1.6
 36000 -49.9 -57.8  260  70 36   3.9   2.1 | -48.7 -55.7  260  66 34   2.9   1.6
 34000 -47.4 -53.3  260  73 38   6.7   3.7 | -46.8 -52.2  260  69 36   4.0   2.2
 32000 -43.1 -45.6  260  70 36   6.4   3.5 | -44.3 -47.7  260  66 34   4.3   2.4
 30000 -39.4 -38.9  260  67 34   5.6   3.1 | -41.3 -42.3  260  61 32   4.8   2.6
 29000 -37.7 -35.9  260  63 32   5.7   3.1 | -39.9 -39.8  265  58 30   4.7   2.6
 28000 -36.0 -32.8  260  60 31   5.7   3.1 | -38.5 -37.3  265  54 28   4.7   2.6
 27000 -34.3 -29.7  260  56 29   5.6   3.1 | -37.1 -34.8  265  51 26   4.6   2.5
 26000 -32.6 -26.7  260  52 27   5.6   3.1 | -35.2 -31.4  265  48 25   6.9   3.8
 25000 -30.9 -23.6  260  48 24   5.6   3.1 | -33.1 -27.6  265  45 23   6.9   3.8
 24000 -29.3 -20.7  260  43 22   5.5   3.0 | -31.1 -24.0  270  41 21   6.9   3.8
 23000 -27.4 -17.3  260  40 21   6.7   3.6 | -28.9 -20.0  270  39 20   7.2   4.0
 22000 -25.4 -13.7  260  38 20   6.7   3.7 | -26.8 -16.2  270  37 19   7.3   4.0
 21000 -23.4 -10.1  260  35 18   7.0   3.9 | -24.6 -12.3  270  36 18   7.3   4.0
 20000 -21.0  -5.8  260  34 17   8.3   4.6 | -22.4  -8.3  265  34 17   7.5   4.1
 19500 -19.8  -3.6  260  33 17   8.3   4.6 | -21.3  -6.3  265  33 17   7.5   4.1
 19000 -18.6  -1.5  260  32 16   8.3   4.6 | -20.2  -4.4  265  32 16   7.6   4.1
 18500 -16.7   1.9  255  31 16   8.2   4.5 | -19.1  -2.4  265  31 16   7.6   4.2
 18000 -15.5   4.1  260  31 16   8.1   4.4 | -18.0  -0.4  260  30 16   7.8   4.3
 17500 -14.3   6.3  260  31 16   8.1   4.4 | -16.8   1.8  260  30 15   7.8   4.3
 17000 -13.2   8.2  260  31 16   7.9   4.3 | -15.1   4.8  260  29 15   8.1   4.5
 16500 -12.0  10.4  260  30 16   7.9   4.3 | -13.9   7.0  260  28 15   8.1   4.5
 16000 -10.9  12.4  260  30 15   7.3   4.0 | -12.7   9.1  260  27 14   8.2   4.5
 15500  -9.8  14.4  260  28 14   7.2   4.0 | -11.5  11.3  260  26 14   8.3   4.5
 15000  -8.8  16.2  260  26 14   7.1   3.9 | -10.3  13.5  260  25 13   8.2   4.5
 14500  -7.8  18.0  260  25 13   6.9   3.8 |  -9.1  15.6  260  24 12   8.1   4.5
 14000  -6.8  19.8  260  23 12   7.1   3.9 |  -7.9  17.8  255  22 11   8.1   4.5
 13500  -5.6  21.9  260  21 11   8.3   4.5 |  -6.7  19.9  255  20 10   8.1   4.4
 13000  -4.4  24.1  255  19 10   8.2   4.5 |  -5.5  22.1  255  18  9   8.1   4.4
 12500  -3.2  26.2  255  18  9   8.3   4.6 |  -4.3  24.3  255  17  9   8.4   4.6
 12000  -1.9  28.6  255  18  9   8.4   4.6 |  -3.0  26.6  255  17  9   8.3   4.6
 11500  -0.7  30.7  255  17  9   7.9   4.3 |  -1.8  28.8  255  15  8   8.8   4.8
 11000   0.4  32.7  255  17  8   8.0   4.4 |  -0.5  31.1  250  14  7   8.9   4.9
 10500   1.6  34.9  255  16  8   7.4   4.0 |   0.7  33.3  250  12  6   7.3   4.0
 10250   2.1  35.8  255  15  8   8.1   4.5 |   1.3  34.3  250  12  6   9.0   4.9
 10000   2.8  37.0  255  15  7   9.0   4.9 |   2.1  35.8  250  11  6  11.9   6.5
  9750   3.5  38.3  255  14  7   9.3   5.1 |   3.0  37.4  245  10  5  10.4   5.7
  9500   4.2  39.6  255  13  7   9.6   5.3 |   3.6  38.5  245  10  5   8.7   4.8
  9250   4.9  40.8  255  13  6   9.5   5.2 |   4.3  39.7  245   9  5   9.0   5.0
  9000   5.6  42.1  255  12  6   9.3   5.1 |   5.0  41.0  245   9  4   9.9   5.5
  8750   6.3  43.3  255  12  6   9.9   5.4 |   5.8  42.4  240   8  4  10.3   5.6
  8500   7.1  44.8  255  11  6  10.4   5.7 |   6.5  43.7  240   8  4   9.6   5.2
  8250   7.8  46.0  255  11  6  10.9   6.0 |   7.2  45.0  240   8  4   9.9   5.5
  8000   8.6  47.5  255  10  5   8.6   4.7 |   7.9  46.2  235   7  4   9.1   5.0
  7750   9.2  48.6  255  10  5   8.1   4.5 |   8.6  47.5  235   7  4   8.9   4.9
  7500   9.9  49.8  255  10  5  10.3   5.7 |   9.3  48.7  235   7  4   9.6   5.3
  7250  10.6  51.1  255  10  5   9.3   5.1 |  10.0  50.0  235   7  4   9.1   5.0
  7000  11.4  52.5  255  10  5  11.3   6.2 |  10.7  51.3  230   7  3  10.4   5.7
  6750  12.3  54.1  255   9  5  10.9   6.0 |  11.5  52.7  230   6  3  10.2   5.6
  6500  13.0  55.4  255   9  5   8.9   4.9 |  12.2  54.0  230   6  3   8.9   4.9
  6250  13.7  56.7  255   9  5   9.6   5.3 |  12.9  55.2  230   6  3   9.0   4.9
  6000  14.4  57.9  255   8  4   9.8   5.4 |  13.5  56.3  230   5  3   8.5   4.7
  5750  15.2  59.4  260   8  4  12.5   6.9 |  14.0  57.2  235   5  2   4.2   2.3
  5500  16.3  61.3  260   7  4  16.8   9.2 |  14.0  57.2  235   3  2  -2.9  -1.6
________________________________________________________________________________

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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