Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 110122
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1822 MST Tuesday, January 10, 2017

This forecast is for Wednesday, January 11, 2017:

If the trigger temperature of 56.6 F/13.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7473 ft MSL (2123 ft AGL)

Forecast maximum temperature................... 52.0 F/11.6 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................. 5997 ft MSL (647 ft AGL)
Thermal soaring outlook for Thursday 01/12..... Poor

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1700 MST)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 38540 ft MSL (33190 ft AGL)
Wave soaring outlook for Thursday 01/12........ Good

Remarks... Moist westerly flow continues with snow in the mountains, downsloping
           winds along the foothills

Sunrise/Sunset.................... 07:19:57 / 16:55:15 MST
Total possible sunshine........... 9 hr 35 min 19 sec (575 min 19 sec)
Altitude of sun at 12:07:36 MST... 28.53 degrees

Upper air data from numerical model forecast valid on 01/11/2017 at 0500 MST

Freezing level.................. 10348 ft MSL (4998 ft AGL)
Convective condensation level... 16682 ft MSL (11332 ft AGL)
Lifted condensation level....... 13282 ft MSL (7932 ft AGL)
Lifted index.................... +6.3
K index......................... +8.8

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  -66.7 -88.1   260   40   21   3.9   2.1      M     M       M      M    M
 45000  -60.6 -77.1   260   45   23   3.8   2.1      M     M       M      M    M
 40000  -59.5 -75.1   265   56   29   0.3   0.2      M     M       M      M    M
 38000  -58.9 -74.0   265   59   30   2.9   1.6      M     M       M      M    M
 36000  -57.1 -70.8   265   58   30   3.0   1.6      M     M       M      M    M
 34000  -55.4 -67.7   265   58   30   2.7   1.5      M     M       M      M    M
 32000  -50.9 -59.6   270   55   28   7.0   3.9      M     M       M      M    M
 30000  -46.7 -52.1   270   53   27   7.8   4.3   28.5  83.3    13.0      M    M
 29000  -44.3 -47.7   270   51   26   8.0   4.4   27.7  81.8    12.6      M    M
 28000  -41.9 -43.4   270   48   25   8.0   4.4   27.0  80.5    12.2      M    M
 27000  -39.5 -39.1   270   46   24   8.0   4.4   26.4  79.5    11.9      M    M
 26000  -37.0 -34.6   275   44   22   8.5   4.6   25.8  78.5    11.6      M    M
 25000  -34.4 -29.9   270   41   21   8.5   4.6   25.3  77.5    11.3      M    M
 24000  -31.9 -25.4   270   39   20   8.5   4.6   24.9  76.8    11.1      M    M
 23000  -29.4 -20.9   270   37   19   8.0   4.4   24.3  75.8    10.8      M    M
 22000  -27.0 -16.6   270   37   19   8.0   4.4   23.7  74.6    10.4      M    M
 21000  -24.6 -12.3   270   36   19   8.0   4.4   23.1  73.6    10.0      M    M
 20000  -22.3  -8.1   270   36   18   8.0   4.4   22.5  72.5     9.6      M    M
 19500  -21.1  -6.0   270   36   18   8.0   4.4   22.1  71.9     9.4      M    M
 19000  -19.9  -3.8   270   36   18   8.0   4.4   21.9  71.3     9.1      M    M
 18500  -18.1  -0.6   270   36   18   8.0   4.4   21.5  70.6     8.9      M    M
 18000  -16.9   1.6   270   35   18   7.9   4.3   21.2  70.1     8.6      M    M
 17500  -15.7   3.7   270   35   18   7.9   4.3   20.8  69.5     8.4      M    M
 17000  -14.6   5.7   270   34   18   7.6   4.2   20.5  68.9     8.1      M    M
 16500  -13.5   7.7   270   34   18   7.6   4.2   20.1  68.3     7.8      M    M
 16000  -12.3   9.9   270   34   18   7.7   4.2   19.8  67.6     7.5      M    M
 15500  -11.2  11.8   270   33   17   7.9   4.3   19.5  67.0     7.3      M    M
 15000  -10.0  14.0   270   31   16   7.8   4.3   19.1  66.5     7.0      M    M
 14500   -8.8  16.2   270   29   15   8.6   4.7   18.9  66.0     6.8      M    M
 14000   -7.5  18.5   270   27   14   8.6   4.7   18.7  65.6     6.7      M    M
 13500   -6.3  20.7   270   25   13   7.9   4.3   18.4  65.2     6.5      M    M
 13000   -5.1  22.8   270   24   12   7.9   4.3   18.1  64.6     6.2      M    M
 12500   -4.0  24.8   270   24   12   6.7   3.7   17.8  64.0     5.9      M    M
 12000   -3.1  26.4   270   24   12   6.5   3.5   17.2  63.0     5.4      M    M
 11500   -2.1  28.2   270   24   12   6.4   3.5   16.7  62.1     4.9      M    M
 11000   -1.2  29.8   270   24   12   6.4   3.5   16.2  61.1     4.4      M    M
 10500   -0.3  31.5   270   24   13   5.7   3.1   15.6  60.1     3.9      M    M
 10250    0.1  32.2   270   25   13   5.4   3.0   15.3  59.5     3.6      M    M
 10000    0.5  32.9   270   25   13   5.9   3.3   15.0  58.9     3.3      M    M
  9750    1.0  33.8   270   24   13   5.9   3.3   14.7  58.4     3.0      M    M
  9500    1.4  34.5   270   24   12   5.3   2.9   14.3  57.8     2.7      M    M
  9250    1.8  35.2   270   24   12   5.1   2.8   14.0  57.2     2.4      M    M
  9000    2.2  36.0   270   23   12   4.8   2.7   13.6  56.5     2.0      M    M
  8750    2.5  36.5   265   23   12   4.8   2.7   13.2  55.8     1.6      M    M
  8500    2.9  37.2   265   22   11   5.5   3.0   12.9  55.2     1.3      M    M
  8250    3.3  37.9   265   21   11   5.7   3.1   12.6  54.6     1.0      M    M
  8000    3.7  38.7   260   20   10   5.5   3.0   12.2  54.0     0.7      M    M
  7750    4.1  39.4   260   19   10   5.9   3.2   11.9  53.5     0.4      M    M
  7500    4.6  40.3   260   17    9   6.5   3.6   11.7  53.0     0.1      M    M
  7250    5.1  41.2   255   16    8   6.2   3.4   11.4  52.5    -0.2    118  0.6
  7000    5.5  41.9   255   15    8   7.1   3.9   11.1  52.1    -0.4     96  0.5
  6750    6.0  42.8   250   14    7   4.2   2.3   10.9  51.6    -0.7     74  0.4
  6500    6.1  43.0   245   13    6   0.8   0.5   10.3  50.5    -1.3     63  0.3
  6250    6.3  43.3   245   11    6   2.8   1.5    9.7  49.4    -1.9     52  0.3
  6000    6.4  43.5   240   10    5  -1.5  -0.8    9.1  48.3    -2.5     42  0.2
  5750    5.8  42.4   230    9    5 -16.2  -8.9    7.7  45.9    -3.9     53  0.3
  5500    4.0  39.2   225    7    3 -28.2 -15.5    5.2  41.4    -6.4     99  0.5

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

           01/11/2017 at 0800 MST          |       01/11/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +3.4        | CAPE...     0.0    LI...       +2.1
CINH...    -0.3    K Index... +11.1        | CINH...    -0.1    K Index... +12.8
                                           |
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  260  38 19   4.1   2.2 | -65.8 -86.4  255  35 18   3.6   2.0
 45000 -60.3 -76.5  260  43 22   4.0   2.2 | -60.1 -76.2  255  38 19   3.6   2.0
 40000 -58.2 -72.8  260  53 27   1.1   0.6 | -57.4 -71.3  260  50 26   1.6   0.9
 38000 -57.4 -71.3  260  56 29   2.1   1.1 | -56.4 -69.5  260  55 28   2.0   1.1
 36000 -56.2 -69.2  260  57 29   2.1   1.1 | -55.2 -67.4  260  58 30   2.0   1.1
 34000 -54.9 -66.8  260  57 29   1.6   0.9 | -54.0 -65.2  260  61 31   1.7   0.9
 32000 -51.6 -60.9  260  55 28   6.1   3.3 | -51.3 -60.3  260  58 30   5.1   2.8
 30000 -47.5 -53.5  265  51 26   7.2   3.9 | -47.8 -54.0  260  54 28   6.1   3.4
 29000 -45.2 -49.4  265  49 25   7.8   4.3 | -45.7 -50.3  260  51 26   7.2   4.0
 28000 -42.8 -45.0  265  47 24   7.8   4.3 | -43.5 -46.3  260  49 25   7.2   4.0
 27000 -40.5 -40.9  265  45 23   7.8   4.3 | -41.4 -42.5  260  46 24   7.2   4.0
 26000 -38.1 -36.6  265  43 22   8.3   4.5 | -39.1 -38.4  260  44 23   8.0   4.4
 25000 -35.6 -32.1  265  41 21   8.3   4.5 | -36.7 -34.1  260  42 22   8.0   4.4
 24000 -33.2 -27.8  265  39 20   8.3   4.5 | -34.3 -29.7  260  40 20   8.1   4.4
 23000 -30.6 -23.1  265  38 19   8.6   4.7 | -31.9 -25.4  260  37 19   8.2   4.5
 22000 -28.1 -18.6  265  37 19   8.6   4.7 | -29.4 -20.9  260  34 18   8.2   4.5
 21000 -25.5 -13.9  265  36 18   8.6   4.7 | -27.0 -16.6  260  31 16   8.2   4.5
 20000 -23.0  -9.4  265  34 18   8.3   4.6 | -24.5 -12.1  260  29 15   8.3   4.5
 19500 -21.8  -7.2  265  33 17   8.3   4.6 | -23.3  -9.9  260  29 15   8.3   4.5
 19000 -20.5  -4.9  265  33 17   8.3   4.6 | -22.0  -7.6  260  28 14   8.3   4.5
 18500 -19.3  -2.7  265  32 16   8.3   4.6 | -20.8  -5.4  260  27 14   8.3   4.5
 18000 -18.0  -0.4  265  31 16   8.1   4.4 | -19.6  -3.3  260  27 14   8.3   4.5
 17500 -16.3   2.7  265  29 15   7.9   4.4 | -18.4  -1.1  260  27 14   8.3   4.5
 17000 -15.1   4.8  265  28 14   7.5   4.1 | -17.1   1.2  260  26 14   8.2   4.5
 16500 -14.0   6.8  265  27 14   7.4   4.0 | -15.3   4.5  260  26 14   8.1   4.4
 16000 -13.0   8.6  270  26 14   7.3   4.0 | -14.1   6.6  260  26 14   8.1   4.4
 15500 -11.9  10.6  270  26 13   7.2   4.0 | -12.9   8.8  260  26 14   8.0   4.4
 15000 -10.8  12.6  270  26 13   7.3   4.0 | -11.8  10.8  265  26 14   8.0   4.4
 14500  -9.8  14.4  270  26 13   6.9   3.8 | -10.6  12.9  265  26 14   7.9   4.4
 14000  -8.8  16.2  270  25 13   6.9   3.8 |  -9.4  15.1  265  26 14   8.0   4.4
 13500  -7.7  18.1  270  25 13   7.2   4.0 |  -8.2  17.2  265  26 14   7.6   4.2
 13000  -6.6  20.1  270  25 13   7.3   4.0 |  -7.1  19.2  265  26 13   7.7   4.2
 12500  -5.6  21.9  270  24 13   7.3   4.0 |  -6.0  21.2  265  26 13   7.0   3.8
 12000  -4.5  23.9  270  24 13   7.3   4.0 |  -5.0  23.0  265  25 13   6.9   3.8
 11500  -3.4  25.9  270  24 13   7.2   3.9 |  -4.0  24.8  265  24 12   6.9   3.8
 11000  -2.4  27.7  270  24 13   7.1   3.9 |  -3.0  26.6  265  23 12   6.9   3.8
 10500  -1.3  29.7  270  24 13   6.6   3.6 |  -2.0  28.4  265  23 12   6.1   3.4
 10250  -0.8  30.6  270  24 12   6.5   3.6 |  -1.6  29.1  265  22 11   6.2   3.4
 10000  -0.3  31.5  265  24 12   7.2   3.9 |  -1.1  30.0  265  22 11   7.3   4.0
  9750   0.2  32.4  265  24 12   7.4   4.1 |  -0.5  31.1  260  22 11   7.7   4.2
  9500   0.7  33.3  265  24 12   7.2   4.0 |   0.1  32.2  260  21 11   7.3   4.0
  9250   1.3  34.3  265  23 12   7.7   4.2 |   0.6  33.1  260  21 11   7.7   4.2
  9000   1.8  35.2  265  23 12   6.0   3.3 |   1.1  34.0  260  20 10   6.0   3.3
  8750   2.2  36.0  265  23 12   4.7   2.6 |   1.5  34.7  255  20 10   5.4   3.0
  8500   2.6  36.7  260  22 11   6.0   3.3 |   2.0  35.6  255  19 10   7.3   4.0
  8250   3.0  37.4  260  22 11   6.3   3.5 |   2.5  36.5  255  18  9   7.2   4.0
  8000   3.5  38.3  260  21 11   5.6   3.1 |   3.0  37.4  255  17  9   7.1   3.9
  7750   3.9  39.0  255  20 11   5.7   3.1 |   3.6  38.5  250  16  8   7.6   4.2
  7500   4.3  39.7  255  19 10   6.6   3.6 |   4.2  39.6  250  16  8   8.0   4.4
  7250   4.8  40.6  255  18  9   6.4   3.5 |   4.8  40.6  250  15  7   8.2   4.5
  7000   5.3  41.5  250  17  9   6.5   3.6 |   5.3  41.5  250  14  7   7.2   4.0
  6750   5.7  42.3  250  17  9   4.3   2.4 |   5.9  42.6  245  13  7   7.4   4.1
  6500   5.9  42.6  250  15  8   2.3   1.3 |   6.5  43.7  245  12  6   8.4   4.6
  6250   6.1  43.0  245  13  7   3.9   2.1 |   7.1  44.8  245  11  6   8.3   4.6
  6000   6.3  43.3  240  12  6  -0.4  -0.2 |   7.7  45.9  240  10  5   7.7   4.2
  5750   5.8  42.4  235  10  5 -14.5  -7.9 |   8.3  46.9  240   9  4   8.7   4.8
  5500   4.2  39.6  230   7  4 -25.0 -13.7 |   9.0  48.2  235   7  3  12.4   6.8

           01/11/2017 at 1400 MST          |       01/11/2017 at 1700 MST
                                           |
CAPE...   +14.0    LI...       +0.2        | CAPE...   +34.8    LI...       +0.1
CINH...    -7.0    K Index... +17.4        | CINH...    -9.3    K Index... +17.8
                                           |
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 -64.2 -83.6  255  34 18   2.8   1.6 | -65.4 -85.7  250  36 18   3.7   2.0
 45000 -59.9 -75.8  255  35 18   2.8   1.6 | -59.8 -75.6  250  37 19   3.7   2.0
 40000 -57.1 -70.8  255  44 23   1.7   0.9 | -56.1 -69.0  255  41 21   2.3   1.3
 38000 -55.9 -68.6  260  48 25   2.3   1.3 | -54.6 -66.3  255  44 23   2.1   1.2
 36000 -54.5 -66.1  255  52 27   2.3   1.3 | -53.3 -63.9  255  47 24   2.1   1.2
 34000 -53.1 -63.6  255  55 28   2.1   1.1 | -52.0 -61.6  255  51 26   2.0   1.1
 32000 -50.5 -58.9  255  54 28   4.7   2.6 | -49.7 -57.5  255  51 26   4.3   2.4
 30000 -47.7 -53.9  255  52 27   4.5   2.5 | -47.1 -52.8  255  50 26   4.2   2.3
 29000 -45.9 -50.6  255  50 26   6.0   3.3 | -45.7 -50.3  255  49 25   4.9   2.7
 28000 -44.1 -47.4  255  49 25   6.0   3.3 | -44.2 -47.6  255  48 25   4.9   2.7
 27000 -42.3 -44.1  255  47 24   6.0   3.3 | -42.8 -45.0  255  47 24   4.9   2.7
 26000 -40.3 -40.5  255  46 24   8.2   4.5 | -41.2 -42.2  255  46 24   6.4   3.5
 25000 -37.9 -36.2  255  45 23   8.0   4.4 | -39.3 -38.7  255  45 23   6.4   3.5
 24000 -35.5 -31.9  255  44 23   8.0   4.4 | -37.4 -35.3  255  43 22   6.4   3.5
 23000 -33.2 -27.8  255  43 22   7.8   4.3 | -35.4 -31.7  255  41 21   7.7   4.2
 22000 -30.8 -23.4  255  40 21   7.9   4.3 | -33.1 -27.6  255  38 20   7.8   4.3
 21000 -28.5 -19.3  255  37 19   7.8   4.3 | -30.8 -23.4  255  35 18   7.8   4.3
 20000 -25.7 -14.3  255  33 17   6.9   3.8 | -27.9 -18.2  255  32 16   7.4   4.1
 19500 -24.7 -12.5  255  31 16   6.9   3.8 | -26.8 -16.2  255  31 16   7.4   4.1
 19000 -23.7 -10.7  255  29 15   6.9   3.8 | -25.7 -14.3  255  30 15   7.4   4.1
 18500 -22.7  -8.9  255  27 14   6.8   3.7 | -24.6 -12.3  255  28 15   7.4   4.1
 18000 -21.6  -6.9  255  26 13   8.3   4.6 | -23.5 -10.3  255  28 14   7.2   4.0
 17500 -20.3  -4.5  255  24 12   8.4   4.6 | -22.5  -8.5  255  27 14   7.2   3.9
 17000 -19.1  -2.4  255  23 12   8.2   4.5 | -21.4  -6.5  260  27 14   7.3   4.0
 16500 -17.9  -0.2  255  22 11   7.8   4.3 | -20.3  -4.5  260  26 13   7.6   4.2
 16000 -16.7   1.9  255  21 11   7.8   4.3 | -19.2  -2.6  260  26 13   7.6   4.2
 15500 -15.6   3.9  255  20 10   7.4   4.1 | -18.0  -0.4  265  25 13   7.7   4.2
 15000 -14.5   5.9  260  21 11   7.4   4.1 | -16.9   1.6  265  24 12   7.8   4.3
 14500 -13.4   7.9  260  21 11   7.7   4.2 | -15.7   3.7  265  23 12   7.3   4.0
 14000 -12.2  10.0  260  21 11   7.7   4.2 | -14.7   5.5  265  22 11   7.3   4.0
 13500 -11.1  12.0  265  21 11   7.7   4.2 | -13.6   7.5  265  21 11   7.7   4.2
 13000 -10.0  14.0  265  21 11   7.7   4.2 | -12.4   9.7  270  20 10   7.8   4.3
 12500  -8.8  16.2  265  20 10   8.1   4.4 | -11.2  11.8  270  19 10   8.3   4.6
 12000  -7.6  18.3  265  20 10   8.3   4.6 | -10.0  14.0  270  17  9   8.5   4.7
 11500  -6.3  20.7  265  19 10   8.4   4.6 |  -8.7  16.3  265  16  8   8.8   4.8
 11000  -5.1  22.8  265  18  9   8.4   4.6 |  -7.4  18.7  265  15  8   8.9   4.9
 10500  -3.9  25.0  265  17  9   8.1   4.4 |  -6.1  21.0  265  13  7   8.3   4.5
 10250  -3.3  26.1  260  16  8   8.2   4.5 |  -5.5  22.1  265  13  7   7.9   4.4
 10000  -2.6  27.3  260  15  8   9.6   5.2 |  -4.9  23.2  265  12  6   9.8   5.4
  9750  -1.9  28.6  260  15  8  10.1   5.5 |  -4.1  24.6  265  11  6  10.9   6.0
  9500  -1.1  30.0  260  14  7   9.5   5.2 |  -3.3  26.1  265  10  5  10.0   5.5
  9250  -0.4  31.3  260  13  7   9.5   5.2 |  -2.6  27.3  265  10  5  10.2   5.6
  9000   0.3  32.5  260  13  7   9.1   5.0 |  -1.8  28.8  265   9  5   9.5   5.2
  8750   0.9  33.6  260  12  6   9.1   5.0 |  -1.1  30.0  265   9  5   9.7   5.3
  8500   1.6  34.9  260  12  6   9.6   5.3 |  -0.3  31.5  265   9  4  10.5   5.8
  8250   2.4  36.3  260  11  6  10.0   5.5 |   0.4  32.7  270   8  4  10.9   6.0
  8000   3.1  37.6  260  10  5   8.9   4.9 |   1.2  34.2  270   8  4   9.0   5.0
  7750   3.7  38.7  260  10  5   8.6   4.7 |   1.8  35.2  270   8  4   8.4   4.6
  7500   4.4  39.9  260   9  5   9.6   5.3 |   2.5  36.5  270   7  4  10.1   5.5
  7250   5.1  41.2  260   9  4   9.2   5.0 |   3.3  37.9  275   7  4   8.9   4.9
  7000   5.8  42.4  260   8  4   9.9   5.4 |   4.0  39.2  275   7  4  11.8   6.5
  6750   6.6  43.9  265   8  4  10.1   5.5 |   4.9  40.8  280   7  3  11.2   6.1
  6500   7.3  45.1  265   7  4   9.6   5.3 |   5.6  42.1  280   7  3   8.2   4.5
  6250   8.0  46.4  265   7  3   9.8   5.4 |   6.2  43.2  285   6  3   8.6   4.7
  6000   8.7  47.7  265   6  3   9.6   5.3 |   6.9  44.4  285   6  3   9.8   5.4
  5750   9.5  49.1  265   6  3  11.0   6.0 |   7.5  45.5  290   5  3   3.9   2.2
  5500  10.4  50.7  270   5  3  13.7   7.5 |   7.2  45.0  295   4  2 -10.2  -5.6
________________________________________________________________________________

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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