Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 280039
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1839 MDT Saturday, September 27, 2014

This forecast is for Sunday, September 28, 2014:

If the trigger temperature of 77.5 F/25.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 773 ft/min (3.9 m/s)
   Maximum height of thermals.................. 13902 ft MSL (8615 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 1200 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8151 ft MSL (2864 ft AGL)
Thermal soaring outlook for Monday 09/29....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change.
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 24694 ft MSL (19407 ft AGL)
Wave soaring outlook for Monday 09/29.......... Poor

Remarks...

Sunrise/Sunset.................... 06:52:50 / 18:48:14 MDT
Total possible sunshine........... 11 hr 55 min 24 sec (715 min 24 sec)
Altitude of sun at 12:50:03 MDT... 48.03 degrees

Upper air data from numerical model forecast valid on 09/28/2014 at 0600 MDT

Freezing level.................. 14884 ft MSL (9597 ft AGL)
Convective condensation level... 13684 ft MSL (8397 ft AGL)
Lifted condensation level....... 13801 ft MSL (8514 ft AGL)
Lifted index.................... -1.2
K index......................... +17.2

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  -66.6 -87.9   230   34   18   1.5   0.8      M     M       M      M    M
 45000  -63.1 -81.6   230   42   22   5.4   3.0      M     M       M      M    M
 40000  -54.4 -65.9   230   45   23   7.2   3.9      M     M       M      M    M
 38000  -50.1 -58.2   215   35   18   7.1   3.9      M     M       M      M    M
 36000  -45.9 -50.6   195   28   14   7.1   3.9      M     M       M      M    M
 34000  -41.3 -42.3   190   26   13   7.7   4.2      M     M       M      M    M
 32000  -36.7 -34.1   185   24   12   7.8   4.3      M     M       M      M    M
 30000  -31.9 -25.4   180   23   12   8.2   4.5   44.5 112.1    13.1      M    M
 29000  -29.4 -20.9   180   22   12   8.2   4.5   43.9 111.0    12.8      M    M
 28000  -26.4 -15.5   175   22   11   7.7   4.2   43.4 110.0    12.5      M    M
 27000  -24.3 -11.7   170   23   12   6.9   3.8   42.2 107.9    11.8      M    M
 26000  -22.2  -8.0   165   25   13   6.9   3.8   41.1 106.0    11.1      M    M
 25000  -20.1  -4.2   165   27   14   6.9   3.8   40.1 104.3    10.4      M    M
 24000  -17.9  -0.2   160   28   14   7.4   4.1   39.2 102.5     9.8      M    M
 23000  -15.7   3.7   160   28   14   7.4   4.1   38.3 100.9     9.1      M    M
 22000  -13.5   7.7   160   28   14   7.5   4.1   37.5  99.5     8.6      M    M
 21000  -11.4  11.5   165   26   13   7.0   3.8   36.5  97.7     7.8      M    M
 20000   -9.3  15.3   170   24   12   7.0   3.8   35.5  96.0     7.1      M    M
 19500   -8.3  17.1   170   23   12   7.0   3.8   35.1  95.2     6.7      M    M
 19000   -7.2  19.0   175   22   11   7.2   3.9   34.7  94.4     6.4      M    M
 18500   -6.1  21.0   175   22   11   7.3   4.0   34.2  93.6     6.0      M    M
 18000   -5.0  23.0   175   22   11   7.5   4.1   33.8  92.9     5.7      M    M
 17500   -4.0  24.8   175   22   11   6.2   3.4   33.3  92.0     5.3      M    M
 17000   -3.1  26.4   175   21   11   6.3   3.5   32.7  90.9     4.8      M    M
 16500   -2.2  28.0   175   20   10   5.5   3.0   32.2  89.9     4.3      M    M
 16000   -1.5  29.3   175   19   10   5.0   2.7   31.3  88.4     3.5      M    M
 15500   -0.8  30.6   175   18    9   4.9   2.7   30.5  87.0     2.8      M    M
 15000   -0.2  31.6   175   16    8   4.0   2.2   29.6  85.3     1.9      M    M
 14500    0.3  32.5   180   14    7   4.1   2.2   28.7  83.7     0.9      M    M
 14000    1.5  34.7   175   12    6   7.7   4.2   27.9  82.2    -0.0    771  3.9
 13500    2.6  36.7   170   11    6   7.9   4.3   27.6  81.7    -0.4    725  3.7
 13000    3.7  38.7   170   11    6   8.5   4.6   27.3  81.2    -0.8    677  3.4
 12500    4.8  40.6   170   10    5   8.6   4.7   27.1  80.8    -1.1    628  3.2
 12000    6.0  42.8   170   11    6   9.1   5.0   27.0  80.6    -1.4    577  2.9
 11500    7.3  45.1   165   11    6   9.1   5.0   26.9  80.4    -1.5    524  2.7
 11000    8.7  47.7   160   12    6   9.3   5.1   26.8  80.3    -1.6    469  2.4
 10500   10.1  50.2   160   12    6   6.9   3.8   26.8  80.2    -1.7    412  2.1
 10250   10.5  50.9   160   12    6   7.4   4.1   26.5  79.6    -2.0    392  2.0
 10000   11.3  52.3   155   11    6  11.1   6.1   26.5  79.7    -2.0    361  1.8
  9750   12.1  53.8   150   11    6  10.1   5.5   26.5  79.8    -1.9    331  1.7
  9500   12.8  55.0   150   11    6  10.6   5.8   26.6  79.9    -1.9    300  1.5
  9250   13.6  56.5   145   11    6   8.8   4.8   26.6  79.9    -1.9    270  1.4
  9000   14.1  57.4   145   10    5   7.0   3.8   26.5  79.6    -2.0    246  1.2
  8750   14.7  58.5   140    9    5   7.3   4.0   26.3  79.3    -2.2    222  1.1
  8500   15.2  59.4   140    9    4   7.0   3.8   26.1  78.9    -2.4    198  1.0
  8250   15.6  60.1   135    7    4   1.9   1.0   25.7  78.3    -2.7    179  0.9
  8000   15.6  60.1   140    5    3  -1.8  -1.0   24.9  76.8    -3.5    174  0.9
  7750   15.5  59.9   140    3    2  -1.1  -0.6   24.0  75.3    -4.3    169  0.9
  7500   15.4  59.7   145    1    1  -1.5  -0.8   23.2  73.7    -5.2    164  0.8
  7250   15.3  59.5   330    1    1  -1.7  -0.9   22.3  72.2    -6.0    161  0.8
  7000   15.1  59.2   335    3    2  -1.9  -1.1   21.4  70.6    -7.0    159  0.8
  6750   14.9  58.8   335    5    3  -2.3  -1.3   20.5  69.0    -7.9    158  0.8
  6500   14.6  58.3   330    7    4  -3.1  -1.7   19.6  67.3    -8.9    158  0.8
  6250   14.3  57.7   330    8    4  -3.4  -1.9   18.6  65.5   -10.0    160  0.8
  6000   14.0  57.2   325    8    4  -3.6  -2.0   17.6  63.7   -11.0    161  0.8
  5750   13.7  56.7   325    8    4  -2.3  -1.2   16.6  61.9   -12.1    162  0.8
  5500   13.7  56.7   320    6    3   2.3   1.2   15.9  60.7   -12.8    156  0.8

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

           09/28/2014 at 0900 MDT          |       09/28/2014 at 1200 MDT
                                           |
K index... +12.4  LI... -1.0               | K index... +15.8  LI... -0.4
CAPE... +253.2  CIN... -12.4               | CAPE... +2.1  CIN... -12.6
                                           |
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  215  34 18   1.8   1.0 | -66.1 -87.0  215  46 24   2.7   1.5
 45000 -62.6 -80.7  220  43 22   4.6   2.5 | -61.8 -79.2  220  52 27   3.8   2.1
 40000 -55.1 -67.2  220  48 25   7.4   4.1 | -55.5 -67.9  225  51 26   7.0   3.9
 38000 -50.7 -59.3  210  41 21   7.2   4.0 | -51.4 -60.5  220  48 25   6.8   3.7
 36000 -46.4 -51.5  200  35 18   7.2   4.0 | -47.3 -53.1  210  46 23   6.9   3.8
 34000 -41.7 -43.1  190  33 17   8.2   4.5 | -42.1 -43.8  205  42 22   9.3   5.1
 32000 -36.7 -34.1  185  33 17   8.2   4.5 | -36.6 -33.9  200  38 20   9.3   5.1
 30000 -32.1 -25.8  180  31 16   7.5   4.1 | -31.7 -25.1  195  36 19   7.6   4.2
 29000 -29.9 -21.8  180  30 15   7.5   4.1 | -29.4 -20.9  195  36 18   7.6   4.2
 28000 -27.0 -16.6  180  28 14   7.5   4.1 | -26.6 -15.9  190  35 18   7.7   4.2
 27000 -24.8 -12.6  175  28 14   7.5   4.1 | -24.3 -11.7  190  34 17   7.7   4.2
 26000 -22.6  -8.7  175  28 14   7.5   4.1 | -22.0  -7.6  185  32 16   7.8   4.3
 25000 -20.3  -4.5  175  27 14   7.5   4.1 | -19.7  -3.5  185  30 16   7.9   4.3
 24000 -18.1  -0.6  175  27 14   7.2   4.0 | -17.6   0.3  180  30 15   6.7   3.6
 23000 -16.0   3.2  175  27 14   7.2   4.0 | -15.6   3.9  175  29 15   6.7   3.7
 22000 -13.8   7.2  175  26 14   7.2   4.0 | -13.6   7.5  175  29 15   6.7   3.7
 21000 -11.7  10.9  175  26 13   7.1   3.9 | -11.6  11.1  175  28 14   6.3   3.5
 20000  -9.5  14.9  175  25 13   7.2   3.9 |  -9.8  14.4  175  27 14   6.3   3.5
 19500  -8.5  16.7  175  25 13   7.2   3.9 |  -8.8  16.2  175  27 14   6.3   3.5
 19000  -7.4  18.7  175  24 12   6.9   3.8 |  -7.9  17.8  175  26 14   6.2   3.4
 18500  -6.4  20.5  180  24 12   6.8   3.7 |  -7.0  19.4  175  26 13   6.1   3.4
 18000  -5.4  22.3  180  24 12   6.8   3.7 |  -6.1  21.0  180  25 13   6.2   3.4
 17500  -4.4  24.1  180  24 12   6.6   3.6 |  -5.2  22.6  180  24 12   5.6   3.1
 17000  -3.4  25.9  180  24 12   6.6   3.6 |  -4.4  24.1  180  23 12   5.7   3.1
 16500  -2.5  27.5  175  23 12   5.9   3.2 |  -3.5  25.7  180  21 11   5.8   3.2
 16000  -1.7  28.9  175  22 11   5.5   3.0 |  -2.7  27.1  180  20 10   5.9   3.3
 15500  -0.9  30.4  175  20 10   5.3   2.9 |  -1.8  28.8  180  19 10   6.0   3.3
 15000  -0.2  31.6  175  18  9   4.5   2.5 |  -1.0  30.2  180  19 10   6.0   3.3
 14500   0.4  32.7  170  16  8   4.7   2.6 |  -0.1  31.8  180  18  9   5.9   3.2
 14000   1.4  34.5  170  14  7   6.2   3.4 |   1.3  34.3  175  17  9   7.3   4.0
 13500   2.1  35.8  170  12  6   7.0   3.8 |   2.3  36.1  170  17  9   7.5   4.1
 13000   3.2  37.8  170  12  6   9.0   4.9 |   3.4  38.1  175  16  8   8.2   4.5
 12500   4.4  39.9  170  12  6   9.0   4.9 |   4.5  40.1  175  15  8   8.3   4.5
 12000   5.6  42.1  170  12  6   8.3   4.5 |   5.6  42.1  180  15  8   7.8   4.3
 11500   6.7  44.1  170  12  6   8.3   4.6 |   6.6  43.9  185  14  7   7.9   4.3
 11000   8.0  46.4  170  11  6   9.9   5.4 |   7.9  46.2  185  14  7   9.6   5.3
 10500   9.4  48.9  170  11  6   9.4   5.2 |   9.2  48.6  190  14  7   5.7   3.1
 10250  10.0  50.0  170  11  6   6.0   3.3 |   9.5  49.1  190  14  7   5.4   3.0
 10000  10.5  50.9  170  11  6   6.8   3.8 |  10.1  50.2  190  13  7  10.3   5.6
  9750  11.1  52.0  170  10  5   9.3   5.1 |  10.8  51.4  190  13  7   9.0   4.9
  9500  11.8  53.2  170  10  5   9.1   5.0 |  11.5  52.7  190  13  7   9.4   5.2
  9250  12.4  54.3  165  10  5   5.2   2.9 |  12.1  53.8  195  12  6   6.7   3.7
  9000  12.7  54.9  165   9  5   2.1   1.1 |  12.5  54.5  195  12  6   6.0   3.3
  8750  12.9  55.2  170   8  4   3.3   1.8 |  13.0  55.4  195  11  6   7.7   4.2
  8500  13.1  55.6  170   7  3   2.9   1.6 |  13.6  56.5  195  10  5   6.8   3.7
  8250  13.4  56.1  170   5  3   3.1   1.7 |  14.0  57.2  190   9  5   4.6   2.5
  8000  13.6  56.5  170   4  2   2.3   1.3 |  14.3  57.7  190   8  4   2.5   1.4
  7750  13.7  56.7  175   3  1   1.6   0.9 |  14.4  57.9  190   7  3   1.9   1.1
  7500  13.8  56.8  190   1  1   0.7   0.4 |  14.6  58.3  185   5  3   2.0   1.1
  7250  13.8  56.8  280   1  1  -0.6  -0.3 |  14.7  58.5  185   3  2   1.9   1.1
  7000  13.7  56.7  315   3  1  -1.0  -0.5 |  14.8  58.6  165   1  0   2.9   1.6
  6750  13.6  56.5  320   5  2  -1.6  -0.9 |  15.0  59.0  030   1  1   5.2   2.9
  6500  13.4  56.1  325   6  3  -1.2  -0.7 |  15.5  59.9  020   2  1   9.4   5.1
  6250  13.3  55.9  320   6  3  -0.1  -0.0 |  16.3  61.3  015   2  1  12.0   6.6
  6000  13.2  55.8  320   7  3  -1.2  -0.7 |  17.1  62.8  015   2  1  10.3   5.6
  5750  13.2  55.8  315   7  3   4.3   2.4 |  17.9  64.2  015   2  1  12.5   6.8
  5500  14.0  57.2  310   6  3  17.8   9.8 |  19.2  66.6  015   2  1  21.4  11.7

           09/28/2014 at 1500 MDT          |       09/28/2014 at 1800 MDT
                                           |
K index... +28.1  LI... -2.9               | K index... +25.1  LI... -3.0
CAPE... +642.4  CIN... -1.7                | CAPE... +571.1  CIN... -8.5
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.8 -86.4  220  43 22   1.4   0.8 | -64.5 -84.1  230  38 20  -0.6  -0.3
 45000 -62.9 -81.2  225  56 29   3.6   2.0 | -63.9 -83.0  230  53 27   4.3   2.4
 40000 -56.8 -70.2  230  52 27   8.6   4.7 | -57.2 -71.0  225  44 23   7.6   4.2
 38000 -51.9 -61.4  220  47 24   8.2   4.5 | -52.2 -62.0  225  42 22   8.3   4.5
 36000 -47.0 -52.6  215  42 22   8.2   4.5 | -47.3 -53.1  225  40 21   8.3   4.5
 34000 -42.0 -43.6  210  40 21   8.3   4.6 | -41.9 -43.4  220  38 20   7.8   4.3
 32000 -37.0 -34.6  210  39 20   8.4   4.6 | -37.2 -35.0  215  36 18   7.9   4.3
 30000 -32.2 -26.0  210  38 20   8.1   4.4 | -32.2 -26.0  210  33 17   8.5   4.6
 29000 -29.8 -21.6  210  37 19   8.1   4.4 | -29.6 -21.3  210  31 16   8.5   4.6
 28000 -27.4 -17.3  205  37 19   8.2   4.5 | -27.1 -16.8  210  29 15   8.3   4.6
 27000 -24.6 -12.3  205  37 19   7.3   4.0 | -25.1 -13.2  210  30 16   6.5   3.6
 26000 -22.5  -8.5  205  38 20   7.4   4.0 | -23.1  -9.6  210  33 17   6.5   3.6
 25000 -20.3  -4.5  205  39 20   7.4   4.1 | -21.1  -6.0  215  35 18   6.5   3.6
 24000 -18.2  -0.8  200  37 19   6.9   3.8 | -18.9  -2.0  215  36 19   8.4   4.6
 23000 -16.2   2.8  205  33 17   6.9   3.8 | -16.3   2.7  215  38 19   8.4   4.6
 22000 -14.2   6.4  205  30 15   7.0   3.8 | -13.8   7.2  215  39 20   8.6   4.7
 21000 -12.2  10.0  200  28 14   6.6   3.6 | -11.9  10.6  215  36 19   5.2   2.9
 20000 -10.3  13.5  200  26 14   6.6   3.6 | -10.4  13.3  215  32 17   5.3   2.9
 19500  -9.3  15.3  200  26 13   6.6   3.6 |  -9.6  14.7  210  30 16   5.4   3.0
 19000  -8.4  16.9  200  25 13   6.5   3.6 |  -8.9  16.0  210  28 15   6.1   3.4
 18500  -7.4  18.7  205  24 13   6.4   3.5 |  -7.9  17.8  210  28 15   7.4   4.1
 18000  -6.5  20.3  205  24 12   6.4   3.5 |  -6.8  19.8  210  29 15   7.6   4.2
 17500  -5.5  22.1  210  24 12   6.6   3.6 |  -5.8  21.6  210  29 15   6.9   3.8
 17000  -4.6  23.7  215  24 12   6.6   3.6 |  -4.1  24.6  215  30 16   7.2   4.0
 16500  -3.6  25.5  215  24 12   6.5   3.6 |  -3.2  26.2  220  30 15   5.1   2.8
 16000  -2.7  27.1  215  24 12   6.5   3.6 |  -2.5  27.5  220  28 14   5.3   2.9
 15500  -1.7  28.9  215  24 12   6.5   3.6 |  -1.7  28.9  220  25 13   5.9   3.3
 15000  -0.8  30.6  215  23 12   6.1   3.4 |  -0.9  30.4  215  22 12   6.4   3.5
 14500   0.1  32.2  210  23 12   6.2   3.4 |  -0.1  31.8  210  20 10   6.9   3.8
 14000   1.4  34.5  200  21 11   6.4   3.5 |   0.9  33.6  200  17  9   7.8   4.3
 13500   2.3  36.1  190  19 10   6.6   3.6 |   2.0  35.6  190  15  8   8.0   4.4
 13000   3.3  37.9  185  18  9   7.2   3.9 |   3.2  37.8  180  14  7   9.3   5.1
 12500   4.3  39.7  175  17  9   7.2   3.9 |   4.5  40.1  175  14  7   9.2   5.0
 12000   5.3  41.5  170  17  9   7.5   4.1 |   5.9  42.6  175  14  7   9.8   5.4
 11500   6.4  43.5  160  16  8   7.4   4.1 |   7.4  45.3  175  13  7   9.9   5.4
 11000   7.5  45.5  160  15  8   8.9   4.9 |   8.7  47.7  175  13  7   8.3   4.6
 10500   8.8  47.8  155  14  7  11.7   6.4 |  10.0  50.0  170  13  7  10.1   5.6
 10250   9.8  49.6  155  14  7  12.4   6.8 |  10.9  51.6  170  13  7  12.1   6.7
 10000  10.5  50.9  155  13  7   9.0   4.9 |  11.7  53.1  170  12  6  10.0   5.5
  9750  11.2  52.2  150  13  7   9.9   5.4 |  12.4  54.3  170  12  6   9.2   5.0
  9500  11.9  53.4  150  12  6   9.7   5.3 |  13.0  55.4  170  11  6   9.6   5.2
  9250  12.6  54.7  150  12  6   8.8   4.8 |  13.7  56.7  170  11  5   8.8   4.8
  9000  13.2  55.8  145  10  5   8.5   4.7 |  14.3  57.7  170  10  5   8.5   4.6
  8750  13.8  56.8  140   9  5   9.1   5.0 |  15.0  59.0  165   9  4   8.9   4.9
  8500  14.5  58.1  130   8  4   9.0   4.9 |  15.6  60.1  165   8  4   8.8   4.8
  8250  15.1  59.2  125   7  4   9.5   5.2 |  16.3  61.3  165   6  3   9.3   5.1
  8000  15.8  60.4  120   6  3   9.7   5.3 |  16.9  62.4  165   5  2   8.9   4.9
  7750  16.5  61.7  115   6  3   9.4   5.2 |  17.5  63.5  165   3  2   8.1   4.4
  7500  17.2  63.0  110   6  3   9.6   5.3 |  18.1  64.6  165   2  1   8.5   4.6
  7250  17.9  64.2  110   5  3  10.1   5.5 |  18.8  65.8  175   1  1   9.2   5.0
  7000  18.7  65.7  105   5  3  10.1   5.5 |  19.4  66.9  290   1  0   9.5   5.2
  6750  19.4  66.9  105   5  3   9.5   5.2 |  20.1  68.2  320   1  1   9.0   4.9
  6500  20.1  68.2  105   5  2  10.0   5.5 |  20.8  69.4  320   2  1   9.5   5.2
  6250  20.9  69.6  100   4  2  11.0   6.0 |  21.6  70.9  325   3  1  10.3   5.7
  6000  21.7  71.1  100   4  2  10.3   5.6 |  22.3  72.1  325   3  2  10.2   5.6
  5750  22.5  72.5  095   4  2  11.2   6.2 |  23.0  73.4  325   4  2   9.0   4.9
  5500  23.5  74.3  090   4  2  18.1   9.9 |  23.7  74.7  325   4  2   8.0   4.4
________________________________________________________________________________

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.

CIN (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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