Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 031242
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0642 MDT Monday, August 3, 2015

This forecast is for Monday, August 3, 2015:

If the trigger temperature of 82.0 F/27.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 447 ft/min (2.3 m/s)
   Maximum height of thermals.................. 12917 ft MSL (7632 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ 1400 MDT
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8561 ft MSL (3276 ft AGL)
Thermal soaring outlook for Tuesday 08/04...... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Improving
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 15841 ft MSL (10556 ft AGL)
Wave soaring outlook for Tuesday 08/04......... Fair

Remarks...

Sunrise/Sunset.................... 06:00:07 / 20:11:34 MDT
Total possible sunshine........... 14 hr 11 min 27 sec (851 min 27 sec)
Altitude of sun at 13:05:35 MDT... 67.64 degrees

Upper air data from rawinsonde observation taken on 08/03/2015 at 0600 MDT

Freezing level.................. 15576 ft MSL (10291 ft AGL)
Convective condensation level... 15020 ft MSL (9735 ft AGL)
Lifted condensation level....... 14839 ft MSL (9553 ft AGL)
Lifted index.................... -2.8
K index......................... +14.6

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  -68.0 -90.4   280   24   12   6.6   3.6   78.4 173.2    28.3      M    M
 45000  -60.8 -77.4   260   59   31   5.7   3.1   66.2 151.1    22.6      M    M
 40000  -51.2 -60.2   255   41   21   1.1   0.6   57.5 135.5    18.5      M    M
 38000  -48.7 -55.7   240   34   17   8.9   4.9   52.7 126.9    15.6      M    M
 36000  -43.6 -46.5   245   27   14   8.5   4.7   51.7 125.0    15.3      M    M
 34000  -38.5 -37.3   250   25   13   8.4   4.6   50.6 123.1    14.9      M    M
 32000  -33.4 -28.1   230   22   11   8.5   4.7   49.6 121.2    14.5      M    M
 30000  -28.5 -19.3   235   19   10   8.0   4.4   48.4 119.1    13.9      M    M
 29000  -26.1 -15.0   235   18    9   8.1   4.4   47.7 117.9    13.5      M    M
 28000  -23.8 -10.8   240   17    9   8.1   4.4   47.1 116.8    13.2      M    M
 27000  -20.8  -5.4   225   16    8   8.2   4.5   46.3 115.3    12.7      M    M
 26000  -18.7  -1.7   205   17    9   6.5   3.6   45.3 113.5    12.0      M    M
 25000  -16.8   1.8   185   19   10   3.8   2.1   44.1 111.4    11.1      M    M
 24000  -17.1   1.2   120   19   10   0.4   0.2   40.1 104.2     8.0      M    M
 23000  -15.6   3.9   120   18    9   9.9   5.4   38.3 101.0     6.7      M    M
 22000  -12.9   8.8   120   18    9   9.0   4.9   38.1 100.7     6.6      M    M
 21000  -10.3  13.5   120   17    9   3.2   1.8   37.7  99.8     6.3      M    M
 20000   -9.9  14.2   155   16    8   4.0   2.2   34.8  94.6     3.9      M    M
 19500   -9.2  15.4   160   19   10   7.0   3.8   34.1  93.4     3.1      M    M
 19000   -8.2  17.2   165   22   11   7.7   4.3   33.6  92.5     2.7      M    M
 18500   -6.9  19.6   155   20   11   9.0   4.9   33.5  92.3     2.5      M    M
 18000   -5.7  21.7   145   19   10   7.8   4.3   33.2  91.8     2.3      M    M
 17500   -4.5  23.9   135   19   10   8.2   4.5   32.9  91.2     2.0      M    M
 17000   -3.4  25.9   120   20   10   5.7   3.1   32.4  90.4     1.7      M    M
 16500   -2.4  27.7   125   22   11   7.0   3.8   31.9  89.4     1.2      M    M
 16000   -1.5  29.3   130   24   12   8.6   4.7   31.4  88.6     0.7      M    M
 15500   -0.1  31.8   130   24   12   9.0   5.0   31.4  88.5     0.7      M    M
 15000    1.3  34.3   125   24   12   9.3   5.1   31.3  88.4     0.6      M    M
 14500    2.6  36.7   125   23   12   9.3   5.1   31.2  88.2     0.4      M    M
 14000    3.9  39.0   130   22   11   8.8   4.9   31.1  88.1     0.3      M    M
 13500    5.9  42.6   135   21   11   8.8   4.8   30.9  87.6     0.1      M    M
 13000    7.3  45.1   145   20   10   8.8   4.8   30.7  87.3    -0.0    644  3.3
 12500    8.4  47.1   150   19   10   7.4   4.1   30.5  86.8    -0.3    595  3.0
 12000    9.5  49.1   155   19   10   7.4   4.1   30.1  86.2    -0.7    548  2.8
 11500   10.7  51.3   160   20   10   9.4   5.2   29.9  85.8    -0.9    497  2.5
 11000   12.3  54.1   165   20   10   9.6   5.3   29.8  85.7    -0.8    436  2.2
 10500   13.8  56.8   170   21   11   9.3   5.1   29.9  85.7    -0.7    375  1.9
 10250   14.6  58.3   175   21   11   8.9   4.9   29.8  85.6    -0.7    345  1.8
 10000   15.3  59.5   175   20   11   7.8   4.3   29.7  85.5    -0.7    316  1.6
  9750   15.8  60.4   180   20   10   4.7   2.6   29.4  85.0    -1.0    294  1.5
  9500   15.8  60.4   185   20   10   5.1   2.8   29.0  84.2    -1.7    286  1.5
  9250   15.9  60.6   185   20   10   7.3   4.0   28.7  83.7    -2.3    276  1.4
  9000   16.4  61.5   190   20   10   7.7   4.2   28.6  83.4    -2.6    254  1.3
  8750   16.9  62.4   190   19   10   7.6   4.2   28.4  83.1    -2.8    232  1.2
  8500   17.3  63.1   190   18    9   7.9   4.4   28.3  82.9    -3.1    210  1.1
  8250   17.9  64.2   185   18    9   8.8   4.8   28.1  82.7    -3.2    185  0.9
  8000   18.6  65.5   185   17    9   9.1   5.0   28.1  82.6    -3.3    157  0.8
  7750   19.3  66.7   185   16    8   9.0   4.9   28.0  82.5    -3.3    129  0.7
  7500   20.0  68.0   185   15    8   9.0   5.0   28.0  82.4    -3.4    101  0.5
  7250   20.7  69.3   185   14    7   9.0   5.0   27.9  82.3    -3.4     73  0.4
  7000   21.4  70.5   185   13    7   9.0   5.0   27.9  82.2    -3.4     45  0.2
  6750   22.1  71.8   190   13    7   9.0   4.9   27.8  82.1    -3.5     16  0.1
  6500   22.8  73.0   190   12    6   9.2   5.1   27.8  82.0    -3.5      M    M
  6250   23.2  73.8   195   12    6  -1.5  -0.8   27.5  81.4    -3.8      M    M
  6000   22.5  72.5   200   12    6 -13.7  -7.5   26.0  78.9    -5.3      M    M
  5750   21.3  70.3   195    9    5 -14.7  -8.1   24.2  75.6    -7.2     10  0.1
  5500   20.1  68.2   180    7    4 -13.6  -7.5   22.4  72.3    -9.1     38  0.2

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

           08/03/2015 at 0900 MDT          |       08/03/2015 at 1200 MDT
                                           |
K index... +22.7  LI... -4.5               | K index... +19.5  LI... -0.8
CAPE... +636.5  CIN... -27.1               | CAPE... +88.3  CIN... -31.1
                                           |
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 -66.3 -87.3  270  36 19   2.2   1.2 | -65.6 -86.1  260  34 18   1.6   0.9
 45000 -60.1 -76.2  265  52 27   8.0   4.4 | -60.3 -76.5  255  49 25   7.6   4.2
 40000 -48.9 -56.0  260  44 23   3.9   2.2 | -49.0 -56.2  250  46 24   5.2   2.9
 38000 -46.5 -51.7  255  35 18   3.9   2.1 | -45.9 -50.6  245  34 17   5.2   2.9
 36000 -43.9 -47.0  240  24 13   6.2   3.4 | -42.7 -44.9  230  23 12   5.6   3.1
 34000 -38.2 -36.8  235  21 11   9.5   5.2 | -37.9 -36.2  230  20 10   8.3   4.6
 32000 -32.5 -26.5  230  17  9  10.4   5.7 | -32.9 -27.2  230  18  9   8.2   4.5
 30000 -27.6 -17.7  225  16  8   8.1   4.4 | -27.9 -18.2  230  18  9   8.5   4.7
 29000 -25.2 -13.4  220  16  8   8.1   4.4 | -24.7 -12.5  230  19 10   8.6   4.7
 28000 -22.8  -9.0  215  15  8   7.7   4.2 | -22.3  -8.1  230  18 10   6.9   3.8
 27000 -20.6  -5.1  210  15  8   7.6   4.2 | -20.3  -4.5  235  17  9   6.9   3.8
 26000 -18.4  -1.1  205  14  7   7.6   4.2 | -18.3  -0.9  240  16  8   7.0   3.8
 25000 -16.2   2.8  205  14  7   7.6   4.2 | -16.3   2.7  245  15  8   6.8   3.7
 24000 -14.6   5.7  180  13  7   4.6   2.5 | -14.5   5.9  240  16  8   5.8   3.2
 23000 -13.3   8.1  160  15  8   4.6   2.5 | -12.8   9.0  240  16  8   5.9   3.2
 22000 -11.9  10.6  140  19 10   4.6   2.5 | -11.1  12.0  235  17  9   5.4   3.0
 21000 -10.6  12.9  140  20 10   4.1   2.2 | -10.0  14.0  220  18  9   3.7   2.1
 20000  -9.3  15.3  140  21 11   4.1   2.2 |  -8.9  16.0  205  21 11   3.8   2.1
 19500  -8.6  16.5  140  21 11   4.0   2.2 |  -8.4  16.9  200  23 12   3.9   2.1
 19000  -7.9  17.8  140  21 11   5.5   3.0 |  -7.9  17.8  195  24 13   2.4   1.3
 18500  -6.7  19.9  140  22 11   5.7   3.1 |  -7.5  18.5  185  25 13   2.4   1.3
 18000  -5.8  21.6  140  23 12   6.6   3.6 |  -7.1  19.2  180  27 14   2.9   1.6
 17500  -4.9  23.2  140  23 12   6.8   3.7 |  -6.5  20.3  175  27 14   4.5   2.5
 17000  -3.9  25.0  140  24 12   7.0   3.9 |  -5.8  21.6  170  28 14   3.9   2.1
 16500  -2.8  27.0  135  24 12   7.6   4.2 |  -4.8  23.4  165  28 14  10.9   6.0
 16000  -1.6  29.1  135  24 12   7.5   4.1 |  -3.1  26.4  160  27 14  11.0   6.0
 15500  -0.5  31.1  135  23 12   8.4   4.6 |  -1.5  29.3  160  26 14  10.1   5.6
 15000   0.7  33.3  135  23 12   8.4   4.6 |   0.6  33.1  155  26 13   9.3   5.1
 14500   1.9  35.4  140  23 12   9.5   5.2 |   1.9  35.4  150  25 13   9.0   4.9
 14000   3.3  37.9  140  23 12   9.9   5.4 |   3.2  37.8  150  24 12   8.9   4.9
 13500   4.7  40.5  145  23 12   9.7   5.3 |   4.5  40.1  145  23 12   8.5   4.7
 13000   6.1  43.0  145  23 12   9.4   5.2 |   5.7  42.3  145  23 12   8.3   4.5
 12500   7.6  45.7  145  23 12   9.2   5.1 |   6.9  44.4  140  22 11   8.0   4.4
 12000   9.1  48.4  150  22 12   8.9   4.9 |   8.0  46.4  140  21 11   7.7   4.2
 11500  10.6  51.1  150  22 11   8.7   4.8 |   9.1  48.4  135  19 10   7.8   4.3
 11000  11.6  52.9  155  20 10   7.6   4.2 |  10.3  50.5  130  18  9   7.9   4.3
 10500  12.6  54.7  155  17  9   5.2   2.9 |  11.5  52.7  130  16  8   4.8   2.7
 10250  12.8  55.0  155  17  9   5.5   3.0 |  11.7  53.1  130  16  8   6.7   3.7
 10000  13.3  55.9  160  16  8   9.7   5.3 |  12.5  54.5  130  15  8  12.2   6.7
  9750  13.8  56.8  165  15  7   9.1   5.0 |  13.3  55.9  125  14  7  11.1   6.1
  9500  14.4  57.9  170  14  7   8.8   4.8 |  14.2  57.6  125  14  7   9.9   5.4
  9250  14.9  58.8  175  13  7   7.5   4.1 |  14.8  58.6  125  13  7   7.9   4.4
  9000  15.4  59.7  175  12  6   8.6   4.7 |  15.4  59.7  125  12  6   9.6   5.3
  8750  16.1  61.0  175  11  6   9.9   5.4 |  16.2  61.2  120  12  6  10.6   5.8
  8500  16.8  62.2  180  11  5   8.6   4.7 |  16.9  62.4  120  11  6  10.3   5.6
  8250  17.4  63.3  175  10  5   7.2   4.0 |  17.7  63.9  120  10  5  10.4   5.7
  8000  17.9  64.2  175   9  4   6.9   3.8 |  18.4  65.1  120  10  5   9.8   5.4
  7750  18.4  65.1  175   8  4   6.6   3.6 |  19.1  66.4  115   9  5   9.0   4.9
  7500  18.9  66.0  175   7  4   6.5   3.6 |  19.8  67.6  115   8  4  10.0   5.5
  7250  19.4  66.9  175   6  3   6.6   3.6 |  20.6  69.1  110   7  4  10.9   6.0
  7000  19.9  67.8  175   6  3   6.3   3.5 |  21.3  70.3  105   7  3  10.2   5.6
  6750  20.3  68.5  180   5  3   5.7   3.1 |  22.0  71.6  100   6  3   9.3   5.1
  6500  20.8  69.4  185   5  2   6.6   3.6 |  22.7  72.9  095   5  3   9.9   5.4
  6250  21.3  70.3  190   4  2   7.9   4.3 |  23.5  74.3  095   5  2  11.0   6.0
  6000  21.8  71.2  195   3  2   6.5   3.6 |  24.3  75.7  090   4  2   9.6   5.2
  5750  22.2  72.0  205   2  1   8.8   4.8 |  25.0  77.0  080   4  2  12.5   6.8
  5500  23.1  73.6  220   1  1  16.8   9.2 |  26.3  79.3  080   3  2  21.7  11.9

           08/03/2015 at 1500 MDT          |       08/03/2015 at 1800 MDT
                                           |
K index... +32.9  LI... -2.0               | K index... +28.2  LI... -2.4
CAPE... +264.6  CIN... -1.2                | CAPE... +414.4  CIN... -34.4
                                           |
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 -65.3 -85.5  260  32 16   1.8   1.0 | -64.6 -84.3  250  29 15   2.2   1.2
 45000 -60.1 -76.2  255  49 25   6.9   3.8 | -59.7 -75.5  245  44 23   5.8   3.2
 40000 -49.5 -57.1  240  50 26   6.0   3.3 | -50.4 -58.7  235  41 21   6.5   3.6
 38000 -45.9 -50.6  225  40 21   6.0   3.3 | -46.6 -51.9  220  33 17   6.5   3.5
 36000 -42.3 -44.1  210  34 18   6.3   3.5 | -42.7 -44.9  200  28 15   6.6   3.6
 34000 -37.7 -35.9  215  29 15   7.9   4.3 | -38.0 -36.4  210  25 13   7.9   4.3
 32000 -33.0 -27.4  225  25 13   7.7   4.2 | -33.3 -27.9  230  24 12   7.7   4.2
 30000 -28.4 -19.1  235  22 12   7.6   4.2 | -28.6 -19.5  240  23 12   7.9   4.3
 29000 -25.6 -14.1  240  21 11   7.6   4.2 | -25.7 -14.3  245  22 11   7.9   4.3
 28000 -23.5 -10.3  245  21 11   6.5   3.6 | -23.4 -10.1  250  21 11   7.4   4.1
 27000 -21.5  -6.7  255  20 11   6.6   3.6 | -21.2  -6.2  255  19 10   7.4   4.1
 26000 -19.6  -3.3  260  21 11   6.6   3.6 | -19.1  -2.4  260  17  9   7.4   4.1
 25000 -17.7   0.1  265  21 11   6.8   3.7 | -16.9   1.6  270  16  8   7.3   4.0
 24000 -15.6   3.9  260  19 10   7.2   3.9 | -15.0   5.0  275  14  7   6.4   3.5
 23000 -13.5   7.7  255  18  9   7.2   4.0 | -13.1   8.4  280  12  6   6.5   3.5
 22000 -11.4  11.5  250  17  9   6.9   3.8 | -11.2  11.8  295  10  5   6.4   3.5
 21000  -9.7  14.5  230  14  7   6.0   3.3 |  -9.5  14.9  300   6  3   5.9   3.2
 20000  -7.9  17.8  200  14  7   6.0   3.3 |  -7.8  18.0  315   2  1   5.9   3.2
 19500  -7.1  19.2  190  15  8   6.1   3.3 |  -6.9  19.6  015   1  1   6.0   3.3
 19000  -6.3  20.7  180  16  8   5.3   2.9 |  -6.1  21.0  085   2  1   5.4   3.0
 18500  -5.5  22.1  170  16  8   5.3   2.9 |  -5.4  22.3  100   4  2   5.4   2.9
 18000  -4.7  23.5  160  17  9   5.4   3.0 |  -4.6  23.7  105   6  3   5.4   3.0
 17500  -3.9  25.0  155  16  8   5.6   3.1 |  -3.8  25.2  105   8  4   5.6   3.1
 17000  -3.1  26.4  150  16  8   5.6   3.1 |  -3.0  26.6  105  10  5   5.7   3.1
 16500  -2.3  27.9  140  16  8   5.7   3.1 |  -2.2  28.0  105  11  6   4.6   2.5
 16000  -1.5  29.3  135  15  8   5.8   3.2 |  -1.6  29.1  105  12  6   4.6   2.5
 15500  -0.7  30.7  130  14  7   6.3   3.4 |  -0.5  31.1  105  13  7   6.3   3.5
 15000   0.7  33.3  120  13  7   6.7   3.7 |   0.4  32.7  105  13  7   6.2   3.4
 14500   1.7  35.1  110  12  6   7.4   4.1 |   1.3  34.3  105  13  7   7.1   3.9
 14000   2.8  37.0  105  11  6   7.6   4.1 |   2.4  36.3  105  13  7   7.5   4.1
 13500   3.9  39.0  100  11  6   6.9   3.8 |   3.5  38.3  110  13  7   7.3   4.0
 13000   4.8  40.6  100  10  5   6.4   3.5 |   4.5  40.1  110  12  6   6.9   3.8
 12500   5.6  42.1  100   9  5   7.2   4.0 |   5.6  42.1  110  12  6   6.9   3.8
 12000   6.8  44.2  100   8  4   8.8   4.9 |   6.6  43.9  115  11  6   7.0   3.9
 11500   8.1  46.6  105   8  4   9.0   4.9 |   7.6  45.7  120  10  5   7.0   3.9
 11000   9.5  49.1  105   7  4   9.2   5.1 |   8.6  47.5  125  10  5   7.0   3.8
 10500  10.9  51.6  110   6  3   5.6   3.1 |   9.6  49.3  135   9  4   4.7   2.6
 10250  11.2  52.2  110   6  3   7.0   3.8 |   9.9  49.8  135   9  4   4.9   2.7
 10000  12.0  53.6  115   6  3  12.7   7.0 |  10.4  50.7  140   8  4   8.8   4.8
  9750  12.9  55.2  115   6  3  11.6   6.4 |  11.1  52.0  145   8  4   8.7   4.8
  9500  13.7  56.7  115   6  3  10.4   5.7 |  11.7  53.1  155   8  4   7.9   4.3
  9250  14.4  57.9  115   6  3   8.4   4.6 |  12.1  53.8  160   8  4   5.9   3.2
  9000  15.1  59.2  120   6  3  10.1   5.5 |  12.6  54.7  165   8  4   7.1   3.9
  8750  15.9  60.6  120   6  3  11.1   6.1 |  13.2  55.8  170   8  4   8.8   4.8
  8500  16.7  62.1  120   5  3  10.5   5.7 |  13.7  56.7  175   8  4   7.7   4.2
  8250  17.5  63.5  120   5  3   9.9   5.4 |  14.2  57.6  180   9  4   6.9   3.8
  8000  18.2  64.8  120   5  3  10.0   5.5 |  14.7  58.5  180   9  5   6.6   3.6
  7750  19.0  66.2  120   5  3  10.2   5.6 |  15.2  59.4  185  10  5   6.5   3.6
  7500  19.7  67.5  125   5  3  10.1   5.6 |  15.6  60.1  190  10  5   6.1   3.4
  7250  20.5  68.9  125   5  3  10.1   5.5 |  16.0  60.8  190  11  6   5.8   3.2
  7000  21.2  70.2  125   5  3  10.1   5.5 |  16.4  61.5  195  12  6   6.0   3.3
  6750  22.0  71.6  130   5  2  10.2   5.6 |  16.8  62.2  200  13  6   6.3   3.5
  6500  22.8  73.0  130   5  2  10.6   5.8 |  17.2  63.0  200  13  7   6.2   3.4
  6250  23.6  74.5  130   4  2  11.2   6.1 |  17.6  63.7  200  13  7   6.4   3.5
  6000  24.4  75.9  135   4  2  10.1   5.5 |  17.9  64.2  205  14  7   5.0   2.7
  5750  25.1  77.2  135   4  2  12.2   6.7 |  18.2  64.8  205  14  7   8.6   4.7
  5500  26.3  79.3  140   4  2  19.7  10.8 |  19.2  66.6  205  12  6  19.6  10.7
________________________________________________________________________________

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.

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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