Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 241253
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0653 MDT Friday, July 24, 2015

This forecast is for Friday, July 24, 2015:

If the trigger temperature of 85.6 F/29.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 999 ft/min (5.1 m/s)
   Maximum height of thermals.................. 16681 ft MSL (11842 ft AGL)

Forecast maximum temperature................... 92.0 F/33.8 C
Time of trigger temperature.................... 1245 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9572 ft MSL (4733 ft AGL)
Thermal soaring outlook for Saturday 07/25..... Excellent

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 06:07:34 / 20:33:56 MDT
Total possible sunshine........... 14 hr 26 min 22 sec (866 min 22 sec)
Altitude of sun at 13:20:35 MDT... 70.66 degrees

Upper air data from rawinsonde observation taken on 07/24/2015 at 0600 MDT

Freezing level.................. 15266 ft MSL (10427 ft AGL)
Convective condensation level... 18402 ft MSL (13563 ft AGL)
Lifted condensation level....... 17868 ft MSL (13029 ft AGL)
Lifted index.................... +2.4
K index......................... +19.9

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  -70.5 -94.9   220   44   23  -6.6  -3.6   76.2 169.1    24.9      M    M
 45000  -61.8 -79.2   240   60   31   7.6   4.1   65.1 149.1    19.8      M    M
 40000  -50.2 -58.4   235   60   31   8.8   4.8   60.4 140.7    18.1      M    M
 38000  -45.1 -49.2   240   60   31   7.6   4.2   59.2 138.6    17.8      M    M
 36000  -41.0 -41.8   240   60   31   4.0   2.2   56.9 134.4    16.6      M    M
 34000  -36.3 -33.3   240   55   28   9.0   5.0   55.1 131.1    15.7      M    M
 32000  -31.7 -25.1   235   48   25   3.3   1.8   52.4 126.4    14.2      M    M
 30000  -27.4 -17.3   230   41   21   4.5   2.5   50.3 122.6    12.9      M    M
 29000  -25.6 -14.1   235   35   18   8.0   4.4   48.9 120.0    11.9      M    M
 28000  -23.3  -9.9   235   34   18   7.9   4.3   48.0 118.5    11.4      M    M
 27000  -20.9  -5.6   235   33   17   7.9   4.3   47.3 117.2    11.0      M    M
 26000  -18.6  -1.5   235   33   17   6.6   3.6   46.6 116.0    10.6      M    M
 25000  -16.7   1.9   235   32   16   6.4   3.5   45.4 113.7     9.7      M    M
 24000  -14.8   5.4   235   30   16   6.5   3.5   43.9 111.1     8.6      M    M
 23000  -12.8   9.0   235   28   15   6.5   3.5   42.6 108.7     7.7      M    M
 22000  -10.9  12.4   230   27   14   6.5   3.5   41.4 106.6     6.7      M    M
 21000   -9.0  15.8   230   25   13   6.5   3.5   40.4 104.7     5.9      M    M
 20000   -7.1  19.2   230   23   12   6.3   3.4   39.4 102.9     5.2      M    M
 19500   -6.6  20.1   225   23   12   0.9   0.5   38.3 100.9     4.2      M    M
 19000   -6.3  20.7   225   23   12   1.8   1.0   36.9  98.5     3.0      M    M
 18500   -6.3  20.7   225   22   12   6.6   3.6   35.5  95.9     1.6      M    M
 18000   -5.3  22.5   220   22   11   7.3   4.0   35.2  95.3     1.2      M    M
 17500   -3.6  25.5   220   22   11   8.6   4.7   34.9  94.7     0.6      M    M
 17000   -2.5  27.5   220   21   11   6.0   3.3   34.4  94.0     0.2      M    M
 16500   -1.9  28.6   215   21   11   0.7   0.4   33.4  92.2    -0.6   1083  5.5
 16000   -1.8  28.8   215   21   11   5.9   3.2   32.0  89.6    -1.9   1064  5.4
 15500   -0.4  31.3   215   20   10   9.1   5.0   31.9  89.4    -2.1   1009  5.1
 15000    1.0  33.8   215   18    9   9.3   5.1   31.8  89.2    -2.2    953  4.8
 14500    2.3  36.1   220   17    9   9.3   5.1   31.7  89.1    -2.3    898  4.6
 14000    3.7  38.7   220   16    8   9.2   5.0   31.7  89.0    -2.3    842  4.3
 13500    5.1  41.2   220   15    8   9.2   5.0   31.6  88.8    -2.4    784  4.0
 13000    6.5  43.7   225   14    7   9.2   5.0   31.5  88.7    -2.5    727  3.7
 12500    8.0  46.4   225   13    7   9.2   5.0   31.4  88.5    -2.5    669  3.4
 12000    9.4  48.9   230   12    6   9.2   5.1   31.4  88.4    -2.5    612  3.1
 11500   10.8  51.4   240   12    6   9.2   5.1   31.3  88.3    -2.6    554  2.8
 11000   12.2  54.0   250   12    6   9.3   5.1   31.2  88.1    -2.7    498  2.5
 10500   13.6  56.5   260   13    7   9.4   5.2   31.1  88.0    -2.7    442  2.2
 10250   14.3  57.7   260   13    7   9.9   5.4   31.1  88.0    -2.8    413  2.1
 10000   15.0  59.0   260   13    7   9.2   5.0   31.1  88.0    -2.8    384  2.0
  9750   15.6  60.1   260   13    6   8.2   4.5   31.0  87.8    -2.9    358  1.8
  9500   16.2  61.2   260   12    6   8.1   4.4   30.9  87.6    -3.0    333  1.7
  9250   16.8  62.2   260   12    6   8.1   4.5   30.8  87.4    -3.2    308  1.6
  9000   17.4  63.3   260   12    6   8.1   4.5   30.6  87.2    -3.3    283  1.4
  8750   18.0  64.4   255   10    5   8.1   4.5   30.5  86.9    -3.5    259  1.3
  8500   18.6  65.5   250    7    4   8.1   4.5   30.4  86.7    -3.6    234  1.2
  8250   19.1  66.4   240    5    3   8.2   4.5   30.3  86.5    -3.8    209  1.1
  8000   19.7  67.5   210    3    2   8.2   4.5   30.1  86.3    -3.9    184  0.9
  7750   20.3  68.5   185    4    2   8.2   4.5   30.0  86.0    -4.1    159  0.8
  7500   20.9  69.6   175    6    3   8.1   4.4   29.9  85.8    -4.2    134  0.7
  7250   21.5  70.7   170    8    4   8.6   4.7   29.8  85.6    -4.4    109  0.6
  7000   22.1  71.8   165   11    5   6.7   3.7   29.6  85.3    -4.6     84  0.4
  6750   22.3  72.1   160   11    6   0.6   0.3   29.2  84.5    -5.0     68  0.3
  6500   22.2  72.0   155   12    6  -3.3  -1.8   28.3  82.9    -5.9     65  0.3
  6250   22.0  71.6   145   13    7   1.2   0.7   27.4  81.3    -6.8     62  0.3
  6000   22.4  72.3   140   14    7   6.5   3.6   27.0  80.6    -7.2     45  0.2
  5750   22.9  73.2   135   13    7   8.3   4.5   26.8  80.3    -7.4     22  0.1
  5500   23.4  74.1   130   11    6   4.0   2.2   26.6  80.0    -7.6      M    M
  5250   23.1  73.6   125   10    5 -15.8  -8.7   25.6  78.0    -8.7      1  0.0
  5000   21.0  69.8   115    8    4 -36.6 -20.1   22.8  73.0   -11.6     56  0.3

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

           07/24/2015 at 0900 MDT          |       07/24/2015 at 1200 MDT
                                           |
K index... +17.8  LI... +277.0             | K index... +22.1  LI... +274.8
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.5
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -66.3 -87.3  250  35 18   0.4   0.2 | -66.0 -86.8  245  32 16   0.2   0.1
 45000 -62.1 -79.8  245  54 28   7.5   4.1 | -61.6 -78.9  240  52 27   7.2   3.9
 40000 -50.2 -58.4  240  64 33   7.7   4.2 | -50.8 -59.4  240  61 32   7.8   4.3
 38000 -45.6 -50.1  240  62 32   7.7   4.2 | -46.1 -51.0  240  60 31   7.8   4.3
 36000 -41.0 -41.8  240  61 31   7.4   4.0 | -41.5 -42.7  235  59 31   7.6   4.2
 34000 -36.6 -33.9  240  53 27   7.2   4.0 | -37.0 -34.6  235  54 28   7.5   4.1
 32000 -32.3 -26.1  240  46 24   7.6   4.2 | -31.9 -25.4  235  48 25   8.1   4.4
 30000 -27.8 -18.0  235  39 20   7.3   4.0 | -27.5 -17.5  235  41 21   7.3   4.0
 29000 -25.6 -14.1  235  35 18   7.3   4.0 | -25.3 -13.5  235  38 19   7.3   4.0
 28000 -23.5 -10.3  235  32 16   6.8   3.7 | -23.2  -9.8  235  34 18   6.4   3.5
 27000 -21.4  -6.5  235  30 15   6.8   3.7 | -21.2  -6.2  235  31 16   6.5   3.6
 26000 -19.4  -2.9  235  27 14   6.8   3.7 | -19.2  -2.6  230  28 14   6.5   3.6
 25000 -17.3   0.9  235  25 13   6.7   3.7 | -17.3   0.9  230  25 13   6.5   3.6
 24000 -15.3   4.5  235  24 12   6.5   3.6 | -15.3   4.5  230  24 13   6.5   3.6
 23000 -13.4   7.9  235  23 12   6.5   3.6 | -13.4   7.9  230  24 12   6.6   3.6
 22000 -11.0  12.2  235  23 12   5.6   3.1 | -11.5  11.3  230  23 12   6.0   3.3
 21000  -9.4  15.1  230  25 13   5.8   3.2 |  -9.9  14.2  225  24 12   5.8   3.2
 20000  -7.7  18.1  230  27 14   6.1   3.4 |  -8.3  17.1  225  25 13   6.2   3.4
 19500  -6.9  19.6  230  28 14   6.0   3.3 |  -7.5  18.5  225  26 13   6.7   3.7
 19000  -6.2  20.8  230  28 14   5.7   3.1 |  -6.4  20.5  225  25 13   9.1   5.0
 18500  -5.4  22.3  230  27 14   5.7   3.1 |  -5.2  22.6  225  24 12   9.0   4.9
 18000  -4.6  23.7  230  27 14   6.3   3.5 |  -3.5  25.7  230  22 11   5.9   3.2
 17500  -3.7  25.3  230  26 13   6.4   3.5 |  -2.6  27.3  230  20 11   6.2   3.4
 17000  -2.8  27.0  225  25 13   7.1   3.9 |  -1.8  28.8  235  19 10   4.8   2.6
 16500  -1.7  28.9  225  23 12   7.8   4.3 |  -1.2  29.8  230  18  9   4.2   2.3
 16000  -0.5  31.1  225  21 11   7.8   4.3 |  -0.6  30.9  225  17  9   4.6   2.5
 15500   0.6  33.1  220  20 10   6.1   3.3 |   0.3  32.5  225  16  8   6.9   3.8
 15000   1.5  34.7  220  17  9   6.0   3.3 |   1.4  34.5  220  15  8   6.9   3.8
 14500   2.6  36.7  220  16  8   8.5   4.7 |   2.4  36.3  220  14  7   6.2   3.4
 14000   3.9  39.0  220  14  7   8.7   4.8 |   3.3  37.9  220  12  6   6.1   3.4
 13500   5.2  41.4  225  13  7   8.4   4.6 |   4.4  39.9  220  11  6   8.9   4.9
 13000   6.5  43.7  230  12  6   8.2   4.5 |   5.9  42.6  220  11  6   9.4   5.1
 12500   7.7  45.9  235  11  6   8.0   4.4 |   7.3  45.1  220  10  5   8.9   4.9
 12000   8.9  48.0  240  11  5   7.8   4.3 |   8.7  47.7  225   9  5   8.7   4.8
 11500  10.1  50.2  245  10  5   8.0   4.4 |  10.0  50.0  230   9  4   8.7   4.8
 11000  11.4  52.5  245  10  5   8.1   4.4 |  11.3  52.3  235   8  4   8.5   4.7
 10500  12.6  54.7  250   9  5   4.8   2.6 |  12.7  54.9  240   8  4   3.3   1.8
 10250  12.8  55.0  250   9  5   5.1   2.8 |  12.7  54.9  240   7  4   5.2   2.8
 10000  13.5  56.3  245   8  4  10.3   5.7 |  13.6  56.5  240   7  4  13.2   7.2
  9750  14.2  57.6  245   8  4  10.2   5.6 |  14.5  58.1  240   7  3  11.7   6.4
  9500  15.0  59.0  245   8  4   8.2   4.5 |  15.3  59.5  240   6  3   8.7   4.8
  9250  15.4  59.7  240   7  4   5.7   3.1 |  15.8  60.4  240   6  3   5.8   3.2
  9000  15.9  60.6  235   6  3   7.3   4.0 |  16.3  61.3  235   6  3   9.2   5.0
  8750  16.5  61.7  225   6  3   8.5   4.7 |  17.1  62.8  235   5  3  10.3   5.7
  8500  17.1  62.8  215   5  3   6.8   3.7 |  17.7  63.9  230   5  2   7.9   4.3
  8250  17.5  63.5  210   4  2   5.4   3.0 |  18.2  64.8  230   5  2   6.6   3.6
  8000  17.9  64.2  205   4  2   5.9   3.2 |  18.8  65.8  225   4  2   6.5   3.6
  7750  18.3  64.9  200   3  2   5.9   3.2 |  19.2  66.6  225   4  2   6.0   3.3
  7500  18.7  65.7  195   3  1   5.3   2.9 |  19.6  67.3  230   4  2   6.5   3.6
  7250  19.0  66.2  195   3  1   4.8   2.6 |  20.1  68.2  235   4  2   7.0   3.8
  7000  19.4  66.9  195   3  1   5.3   2.9 |  20.5  68.9  235   4  2   6.0   3.3
  6750  19.7  67.5  200   2  1   4.3   2.4 |  20.8  69.4  240   4  2   7.3   4.0
  6500  19.9  67.8  190   2  1   2.9   1.6 |  21.5  70.7  240   4  2   9.9   5.4
  6250  20.1  68.2  180   3  1   2.2   1.2 |  22.2  72.0  240   4  2   9.8   5.4
  6000  20.3  68.5  170   3  1   4.1   2.3 |  22.9  73.2  245   4  2  10.4   5.7
  5750  20.7  69.3  160   3  2  10.6   5.8 |  23.8  74.8  240   4  2  14.2   7.8
  5500  21.6  70.9  160   3  1  15.5   8.5 |  25.0  77.0  245   4  2  18.8  10.3
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/24/2015 at 1500 MDT          |       07/24/2015 at 1800 MDT
                                           |
K index... +24.5  LI... +276.2             | K index... +22.9  LI... +274.3
CAPE... 0.0  CIN... -0.6                   | CAPE... 0.0  CIN... -0.2
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -66.6 -87.9  230  33 17   0.7   0.4 | -67.0 -88.6  235  34 17   1.1   0.6
 45000 -61.6 -78.9  235  50 26   7.4   4.1 | -61.4 -78.5  235  46 24   7.6   4.2
 40000 -50.5 -58.9  240  55 29   7.3   4.0 | -50.1 -58.2  240  50 26   7.0   3.9
 38000 -46.1 -51.0  235  55 28   7.3   4.0 | -45.9 -50.6  240  53 27   7.0   3.9
 36000 -41.7 -43.1  235  55 28   8.1   4.4 | -41.6 -42.9  235  55 29   8.0   4.4
 34000 -36.6 -33.9  230  52 27   8.6   4.7 | -36.5 -33.7  235  50 26   8.5   4.7
 32000 -31.4 -24.5  230  49 25   9.4   5.1 | -31.4 -24.5  230  44 23   9.3   5.1
 30000 -26.6 -15.9  230  45 23   7.0   3.9 | -26.9 -16.4  230  39 20   7.4   4.1
 29000 -24.6 -12.3  230  43 22   7.0   3.9 | -24.2 -11.6  230  36 19   7.4   4.1
 28000 -22.6  -8.7  230  41 21   5.6   3.1 | -22.1  -7.8  230  34 18   6.9   3.8
 27000 -20.9  -5.6  230  38 20   5.7   3.1 | -20.0  -4.0  230  33 17   7.0   3.8
 26000 -19.2  -2.6  230  36 18   5.7   3.1 | -18.0  -0.4  230  32 16   7.0   3.8
 25000 -17.5   0.5  230  33 17   7.0   3.8 | -16.0   3.2  230  30 16   6.2   3.4
 24000 -15.3   4.5  230  30 16   7.4   4.1 | -14.3   6.3  230  28 14   5.8   3.2
 23000 -13.1   8.4  225  28 14   7.5   4.1 | -12.5   9.5  230  26 13   5.8   3.2
 22000 -10.9  12.4  225  26 13   7.1   3.9 | -10.8  12.6  230  23 12   5.9   3.2
 21000  -8.9  16.0  225  24 13   7.0   3.9 |  -9.1  15.6  235  22 11   5.9   3.2
 20000  -6.9  19.6  230  23 12   7.1   3.9 |  -7.4  18.7  240  21 11   5.9   3.2
 19500  -5.9  21.4  230  23 12   6.9   3.8 |  -6.5  20.3  245  20 10   6.1   3.3
 19000  -5.0  23.0  230  22 11   5.8   3.2 |  -5.5  22.1  245  20 10   6.9   3.8
 18500  -4.2  24.4  230  21 11   5.9   3.2 |  -4.5  23.9  245  20 10   6.9   3.8
 18000  -3.4  25.9  230  19 10   5.9   3.2 |  -3.5  25.7  250  20 10   6.2   3.4
 17500  -2.6  27.3  235  18  9   5.9   3.2 |  -2.6  27.3  255  19 10   6.0   3.3
 17000  -1.7  28.9  240  17  9   5.8   3.2 |  -1.7  28.9  255  19 10   5.9   3.2
 16500  -0.9  30.4  240  16  8   5.1   2.8 |  -0.9  30.4  260  18  9   5.3   2.9
 16000  -0.2  31.6  245  15  8   5.1   2.8 |  -0.1  31.8  265  18  9   5.2   2.8
 15500   0.7  33.3  245  14  7   6.2   3.4 |   0.8  33.4  270  17  9   7.6   4.1
 15000   1.6  34.9  240  13  7   6.2   3.4 |   1.9  35.4  270  16  8   7.7   4.2
 14500   3.1  37.6  240  12  6   6.8   3.7 |   3.0  37.4  270  16  8   7.6   4.2
 14000   4.1  39.4  235  11  6   6.6   3.6 |   4.6  40.3  260  14  7   7.5   4.1
 13500   5.3  41.5  240  10  5   8.8   4.8 |   5.7  42.3  255  13  7   8.9   4.9
 13000   6.6  43.9  240  10  5   8.8   4.8 |   7.1  44.8  255  12  6   8.9   4.9
 12500   8.0  46.4  240  10  5   8.9   4.9 |   8.4  47.1  250  11  6   8.8   4.8
 12000   9.3  48.7  240   9  5   9.0   4.9 |   9.7  49.5  245  10  5   8.8   4.8
 11500  10.7  51.3  240   9  4   8.8   4.8 |  11.0  51.8  240   9  5   8.9   4.9
 11000  11.9  53.4  240   8  4   8.9   4.9 |  12.3  54.1  235   8  4   9.0   5.0
 10500  13.1  55.6  240   7  4   5.0   2.8 |  13.5  56.3  230   8  4   4.7   2.6
 10250  13.5  56.3  240   7  4   8.0   4.4 |  13.9  57.0  230   7  4   7.4   4.1
 10000  14.3  57.7  240   7  3  11.4   6.2 |  14.7  58.5  225   7  3  11.6   6.4
  9750  15.1  59.2  240   6  3  10.1   5.6 |  15.5  59.9  225   6  3  10.5   5.8
  9500  15.8  60.4  245   6  3   7.0   3.8 |  16.2  61.2  220   6  3   7.6   4.2
  9250  16.2  61.2  245   6  3   6.9   3.8 |  16.7  62.1  215   6  3   6.8   3.7
  9000  16.9  62.4  250   5  3   9.8   5.4 |  17.3  63.1  210   5  3   9.2   5.0
  8750  17.6  63.7  255   5  3   9.6   5.3 |  17.9  64.2  205   5  3   8.8   4.8
  8500  18.3  64.9  255   5  2   9.3   5.1 |  18.6  65.5  200   5  3   7.7   4.2
  8250  19.0  66.2  260   5  2   9.2   5.0 |  19.1  66.4  195   5  2   7.1   3.9
  8000  19.6  67.3  260   5  2   8.9   4.9 |  19.7  67.5  190   5  2   7.5   4.1
  7750  20.3  68.5  260   5  2   9.2   5.1 |  20.2  68.4  185   5  2   7.8   4.3
  7500  21.0  69.8  260   5  2  10.0   5.5 |  20.8  69.4  180   5  2   8.0   4.4
  7250  21.8  71.2  260   5  2  10.0   5.5 |  21.4  70.5  175   4  2   8.3   4.5
  7000  22.5  72.5  260   5  2  10.1   5.5 |  22.0  71.6  175   4  2   7.7   4.2
  6750  23.3  73.9  260   5  2  10.7   5.9 |  22.6  72.7  165   4  2   8.8   4.9
  6500  24.1  75.4  260   5  2  11.0   6.0 |  23.4  74.1  165   4  2  10.3   5.7
  6250  24.9  76.8  260   4  2  11.0   6.0 |  24.1  75.4  165   4  2  10.1   5.6
  6000  25.7  78.3  260   4  2  10.6   5.8 |  24.9  76.8  165   4  2   9.8   5.4
  5750  26.5  79.7  260   4  2  12.0   6.6 |  25.6  78.1  165   4  2   9.2   5.0
  5500  27.4  81.3  260   4  2  13.7   7.5 |  26.2  79.2  165   4  2   9.2   5.0
  5250  28.4  83.1  260   4  2  12.4   6.8 |  26.9  80.4  170   4  2   9.1   5.0
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

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 at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  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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