Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 111246
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0646 MDT Friday, July 11, 2014

This forecast is for Friday, July 11, 2014:

If the trigger temperature of 81.0 F/27.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 796 ft/min (4.0 m/s)
   Maximum height of thermals.................. 14625 ft MSL (9786 ft AGL)

Forecast maximum temperature................... 91.0 F/33.2 C
Time of trigger temperature.................... 1015 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................. 10737 ft MSL (5897 ft AGL)
Thermal soaring outlook for Saturday 07/12..... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:57:49 / 20:41:34 MDT
Total possible sunshine........... 14 hr 43 min 46 sec (883 min 46 sec)
Altitude of sun at 13:19:40 MDT... 72.89 degrees

Upper air data from rawinsonde observation taken on 07/11/2014 at 0600 MDT

Freezing level.................. 16275 ft MSL (11436 ft AGL)
Convective condensation level... 13048 ft MSL (8209 ft AGL)
Lifted condensation level....... 13631 ft MSL (8792 ft AGL)
Lifted index.................... -3.4
K index......................... +29.7

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  -69.3 -92.7   230   19   10   7.7   4.2   77.8 172.1    26.2      M    M
 45000  -59.8 -75.6   200   29   15   6.7   3.7   67.9 154.2    22.0      M    M
 40000  -49.2 -56.6   185   20   10   5.4   3.0   61.9 143.4    19.5      M    M
 38000  -46.5 -51.7   170   16    8   3.9   2.2   57.1 134.8    16.7      M    M
 36000  -42.8 -45.0   185   10    5   5.1   2.8   54.1 129.3    15.0      M    M
 34000  -38.2 -36.8   185   17    9   8.1   4.4   52.3 126.1    14.1      M    M
 32000  -32.1 -25.8   220   18    9   9.5   5.2   51.7 125.1    14.0      M    M
 30000  -27.3 -17.1   220   19   10   8.8   4.8   50.4 122.7    13.3      M    M
 29000  -24.9 -12.8   220   19   10   9.1   5.0   49.8 121.6    12.9      M    M
 28000  -22.2  -8.0   225   19   10   9.1   5.0   49.4 121.0    12.8      M    M
 27000  -20.3  -4.5   225   19   10   2.1   1.2   48.3 118.9    12.0      M    M
 26000  -18.0  -0.4   230   19   10   8.4   4.6   47.5 117.6    11.5      M    M
 25000  -16.1   3.0   230   19   10   3.0   1.6   46.3 115.3    10.6      M    M
 24000  -14.4   6.1   225   17    9   7.5   4.1   44.9 112.8     9.5      M    M
 23000  -12.1  10.2   215   16    8   7.5   4.1   44.2 111.5     9.0      M    M
 22000   -9.8  14.4   220   16    8   7.0   3.8   43.3 110.0     8.4      M    M
 21000   -8.6  16.5   230   17    9  -4.4  -2.4   41.5 106.7     6.9      M    M
 20000   -7.6  18.3   235   18    9   6.3   3.5   39.2 102.6     5.0      M    M
 19500   -6.7  19.9   235   19   10   6.3   3.5   38.6 101.5     4.4      M    M
 19000   -5.8  21.6   240   20   10   6.2   3.4   38.0 100.4     3.9      M    M
 18500   -5.0  23.0   230   20   10   3.6   2.0   37.3  99.1     3.2      M    M
 18000   -4.3  24.3   220   21   11   8.4   4.6   36.6  97.9     2.6      M    M
 17500   -2.4  27.7   215   21   11   9.9   5.4   36.2  97.2     2.2      M    M
 17000   -1.2  29.8   215   21   11   6.2   3.4   35.9  96.7     2.0      M    M
 16500   -0.3  31.5   215   21   11   7.3   4.0   35.5  95.8     1.5      M    M
 16000    0.8  33.4   215   21   11   7.3   4.0   35.1  95.1     1.1      M    M
 15500    1.8  35.2   225   22   11   7.3   4.0   34.6  94.3     0.7      M    M
 15000    2.9  37.2   230   23   12   7.5   4.1   34.2  93.6     0.3      M    M
 14500    3.8  38.8   225   22   11   5.5   3.0   33.7  92.6    -0.3    781  4.0
 14000    4.6  40.3   220   21   11   7.9   4.3   33.1  91.6    -0.9    741  3.8
 13500    5.9  42.6   220   20   10   8.7   4.8   32.9  91.3    -1.1    688  3.5
 13000    7.2  45.0   215   19   10   8.8   4.8   32.8  91.0    -1.3    634  3.2
 12500    8.5  47.3   215   18    9   8.8   4.8   32.6  90.7    -1.4    581  3.0
 12000    9.8  49.6   210   17    9   9.2   5.0   32.5  90.5    -1.6    527  2.7
 11500   10.8  51.4   215   15    8   5.2   2.8   32.1  89.7    -2.0    481  2.4
 11000   11.6  52.9   225   13    7   5.6   3.1   31.4  88.5    -2.7    442  2.2
 10500   12.4  54.3   240   11    6   6.3   3.5   30.8  87.4    -3.3    403  2.0
 10250   13.0  55.4   235   10    5   8.3   4.6   30.6  87.0    -3.5    379  1.9
 10000   13.6  56.5   230   10    5   8.2   4.5   30.5  86.9    -3.6    353  1.8
  9750   14.1  57.4   225    9    5   5.8   3.2   30.3  86.5    -3.8    330  1.7
  9500   14.5  58.1   220    9    4   4.8   2.6   29.9  85.8    -4.2    313  1.6
  9250   14.8  58.6   210    8    4   5.1   2.8   29.5  85.1    -4.6    295  1.5
  9000   15.1  59.2   200    8    4   5.0   2.8   29.2  84.5    -5.0    278  1.4
  8750   15.5  59.9   190    7    4   4.9   2.7   28.8  83.8    -5.4    261  1.3
  8500   15.8  60.4   175    6    3   5.5   3.0   28.4  83.2    -5.9    243  1.2
  8250   16.2  61.2   160    6    3   6.2   3.4   28.1  82.7    -6.2    223  1.1
  8000   16.6  61.9   140    6    3   6.0   3.3   27.9  82.2    -6.5    203  1.0
  7750   17.1  62.8   130    5    3   6.1   3.3   27.6  81.7    -6.8    183  0.9
  7500   17.5  63.5   120    4    2   6.1   3.3   27.3  81.1    -7.1    163  0.8
  7250   17.9  64.2   100    4    2   6.1   3.3   27.0  80.6    -7.4    143  0.7
  7000   18.3  64.9   080    4    2   6.1   3.3   26.8  80.2    -7.7    122  0.6
  6750   18.8  65.8   085    4    2   6.1   3.3   26.5  79.6    -8.1    102  0.5
  6500   19.2  66.6   100    4    2   6.1   3.3   26.2  79.1    -8.4     82  0.4
  6250   19.6  67.3   110    4    2   6.1   3.3   25.9  78.6    -8.7     62  0.3
  6000   20.0  68.0   125    5    2   6.1   3.3   25.6  78.2    -9.0     42  0.2
  5750   20.5  68.9   125    4    2   6.1   3.4   25.4  77.6    -9.4     22  0.1
  5500   20.9  69.6   130    3    2   6.0   3.3   25.1  77.1    -9.7      2  0.0
  5250   21.3  70.3   135    2    1   6.6   3.6   24.8  76.6   -10.0      M    M
  5000   21.7  71.1   155    1    1   4.4   2.4   24.5  76.2   -10.3      M    M

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

           07/11/2014 at 0900 MDT          |       07/11/2014 at 1200 MDT
                                           |
K index... +29.8  LI... -2.4               | K index... +25.4  LI... -2.5
CAPE... +310.2  CIN... -56.9               | CAPE... +429.3  CIN... -16.0
                                           |
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 -66.0 -86.8  210  24 12   1.8   1.0 | -66.1 -87.0  205  24 12   1.8   1.0
 45000 -60.3 -76.5  215  27 14   6.8   3.7 | -60.7 -77.3  215  26 13   6.6   3.6
 40000 -50.2 -58.4  210  24 13   6.7   3.7 | -50.4 -58.7  220  27 14   7.7   4.3
 38000 -46.2 -51.2  210  24 12   6.7   3.7 | -45.8 -50.4  225  26 13   7.7   4.2
 36000 -42.1 -43.8  210  23 12   7.2   4.0 | -41.1 -42.0  230  25 13   7.7   4.2
 34000 -37.3 -35.1  215  20 10   8.1   4.4 | -36.5 -33.7  225  23 12   7.7   4.2
 32000 -32.4 -26.3  220  17  9   8.7   4.8 | -31.3 -24.3  215  22 11   8.3   4.6
 30000 -27.1 -16.8  220  17  9   7.9   4.3 | -26.7 -16.1  210  22 11   7.8   4.3
 29000 -24.7 -12.5  215  17  9   7.9   4.3 | -24.3 -11.7  205  23 12   7.8   4.3
 28000 -22.5  -8.5  215  17  9   6.4   3.5 | -22.1  -7.8  205  23 12   6.6   3.6
 27000 -20.6  -5.1  215  17  9   6.5   3.6 | -20.1  -4.2  205  22 11   6.7   3.7
 26000 -18.6  -1.5  215  17  9   6.6   3.6 | -18.1  -0.6  205  22 11   6.7   3.7
 25000 -16.7   1.9  215  17  9   6.5   3.6 | -16.1   3.0  210  21 11   6.5   3.6
 24000 -14.9   5.2  215  17  9   6.4   3.5 | -14.2   6.4  215  21 11   6.4   3.5
 23000 -13.0   8.6  220  18  9   6.4   3.5 | -12.4   9.7  215  21 11   6.4   3.5
 22000 -11.1  12.0  225  19 10   6.3   3.4 | -10.5  13.1  220  22 11   6.2   3.4
 21000  -9.3  15.3  225  20 10   6.2   3.4 |  -8.7  16.3  225  22 11   6.1   3.4
 20000  -7.5  18.5  225  21 11   6.2   3.4 |  -6.9  19.6  230  22 11   6.1   3.4
 19500  -6.6  20.1  225  21 11   6.2   3.4 |  -6.0  21.2  230  22 11   6.1   3.4
 19000  -5.7  21.7  225  22 11   6.6   3.6 |  -5.1  22.8  230  22 12   6.2   3.4
 18500  -4.7  23.5  225  22 12   6.6   3.6 |  -4.2  24.4  235  23 12   6.2   3.4
 18000  -3.7  25.3  230  23 12   6.3   3.5 |  -3.3  26.1  235  24 12   6.1   3.4
 17500  -2.8  27.0  230  23 12   6.2   3.4 |  -2.3  27.9  240  24 12   6.1   3.4
 17000  -1.9  28.6  230  24 12   6.2   3.4 |  -1.4  29.5  240  25 13   6.1   3.4
 16500  -1.0  30.2  230  24 12   6.8   3.7 |  -0.5  31.1  240  25 13   6.8   3.8
 16000  -0.0  32.0  230  23 12   6.7   3.7 |   0.5  32.9  240  24 13   6.8   3.7
 15500   1.0  33.8  230  23 12   7.3   4.0 |   2.0  35.6  240  24 12   7.2   4.0
 15000   2.5  36.5  230  21 11   7.5   4.1 |   3.0  37.4  235  23 12   7.3   4.0
 14500   3.6  38.5  230  20 10   8.1   4.4 |   4.0  39.2  235  23 12   6.8   3.7
 14000   4.7  40.5  230  19 10   8.1   4.5 |   5.0  41.0  235  22 11   6.9   3.8
 13500   5.8  42.4  225  17  9   7.3   4.0 |   6.0  42.8  235  21 11   6.8   3.7
 13000   6.8  44.2  225  16  8   7.2   4.0 |   6.9  44.4  235  19 10   6.8   3.7
 12500   7.7  45.9  225  14  7   7.0   3.8 |   7.8  46.0  235  18  9   6.8   3.7
 12000   8.7  47.7  220  12  6   6.9   3.8 |   8.7  47.7  235  15  8   6.8   3.7
 11500   9.7  49.5  220  10  5   7.0   3.9 |   9.6  49.3  235  13  7   6.8   3.7
 11000  10.7  51.3  220   9  5   6.9   3.8 |  10.5  50.9  230  10  5   6.7   3.7
 10500  11.7  53.1  220   8  4   3.5   1.9 |  11.4  52.5  225   8  4   4.5   2.5
 10250  11.9  53.4  220   7  4   4.5   2.4 |  11.7  53.1  225   7  4   6.4   3.5
 10000  12.5  54.5  220   7  3   9.6   5.3 |  12.4  54.3  225   7  3  10.6   5.8
  9750  13.1  55.6  220   6  3   8.6   4.7 |  13.1  55.6  225   6  3   9.9   5.4
  9500  13.7  56.7  225   6  3   6.7   3.7 |  13.8  56.8  230   5  3   8.1   4.4
  9250  14.2  57.6  220   6  3   5.6   3.1 |  14.3  57.7  235   4  2   7.3   4.0
  9000  14.7  58.5  215   5  3   7.8   4.3 |  14.9  58.8  240   4  2   9.3   5.1
  8750  15.3  59.5  215   5  3   7.9   4.3 |  15.5  59.9  245   4  2   9.3   5.1
  8500  15.8  60.4  210   5  3   6.8   3.7 |  16.2  61.2  250   3  2   9.4   5.2
  8250  16.3  61.3  205   5  3   6.0   3.3 |  16.9  62.4  250   4  2   9.4   5.2
  8000  16.8  62.2  205   5  3   7.3   4.0 |  17.6  63.7  255   4  2   9.9   5.5
  7750  17.3  63.1  210   5  3   7.9   4.3 |  18.4  65.1  255   4  2  10.3   5.7
  7500  17.9  64.2  205   5  3   6.7   3.7 |  19.1  66.4  260   4  2  10.1   5.6
  7250  18.3  64.9  200   5  3   6.8   3.7 |  19.9  67.8  260   4  2  10.0   5.5
  7000  18.8  65.8  195   5  3   5.8   3.2 |  20.7  69.3  260   4  2  10.4   5.7
  6750  19.2  66.6  190   5  2   7.4   4.0 |  21.4  70.5  260   4  2  11.0   6.0
  6500  19.9  67.8  185   4  2   9.8   5.4 |  22.3  72.1  260   4  2  11.0   6.0
  6250  20.5  68.9  185   3  2   9.8   5.4 |  23.1  73.6  260   4  2  11.3   6.2
  6000  21.2  70.2  180   3  1   8.6   4.7 |  23.9  75.0  260   4  2  10.2   5.6
  5750  21.8  71.2  175   2  1   9.5   5.2 |  24.7  76.5  265   4  2  13.1   7.2
  5500  22.6  72.7  175   2  1  12.1   6.6 |  25.9  78.6  265   4  2  17.0   9.3
  5250  23.5  74.3  175   2  1  10.0   5.5 |  27.1  80.8  265   4  2  14.0   7.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/11/2014 at 1500 MDT          |       07/11/2014 at 1800 MDT
                                           |
K index... +27.0  LI... -2.1               | K index... +27.9  LI... -1.8
CAPE... +307.6  CIN... -24.3               | CAPE... +140.4  CIN... -33.0
                                           |
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  220  21 11   2.0   1.1 | -66.5 -87.7  225  18  9   2.2   1.2
 45000 -60.8 -77.4  230  22 12   6.3   3.5 | -60.8 -77.4  245  19 10   6.4   3.5
 40000 -50.9 -59.6  255  20 10   8.2   4.5 | -50.6 -59.1  270  17  9   8.3   4.5
 38000 -45.9 -50.6  250  22 11   8.2   4.5 | -45.6 -50.1  260  18  9   8.3   4.5
 36000 -41.0 -41.8  245  23 12   7.9   4.4 | -40.6 -41.1  250  20 11   8.1   4.4
 34000 -35.8 -32.4  235  26 13   7.7   4.2 | -35.9 -32.6  245  24 12   7.9   4.3
 32000 -31.2 -24.2  230  29 15   8.3   4.5 | -30.5 -22.9  240  28 14   7.7   4.2
 30000 -26.7 -16.1  220  29 15   7.7   4.2 | -26.2 -15.2  230  30 15   7.4   4.1
 29000 -24.4 -11.9  215  29 15   7.7   4.2 | -24.0 -11.2  230  31 16   7.5   4.1
 28000 -22.2  -8.0  215  29 15   6.4   3.5 | -21.9  -7.4  225  31 16   6.4   3.5
 27000 -20.3  -4.5  215  28 14   6.5   3.6 | -20.0  -4.0  225  30 15   6.5   3.5
 26000 -18.4  -1.1  215  26 14   6.5   3.6 | -18.1  -0.6  220  29 15   6.5   3.6
 25000 -16.5   2.3  220  25 13   6.7   3.7 | -16.2   2.8  220  28 14   6.5   3.5
 24000 -14.4   6.1  220  24 13   6.9   3.8 | -14.3   6.3  220  26 14   6.4   3.5
 23000 -12.4   9.7  220  24 12   6.9   3.8 | -12.4   9.7  225  25 13   6.4   3.5
 22000 -10.4  13.3  225  23 12   6.5   3.6 | -10.5  13.1  225  23 12   6.3   3.5
 21000  -8.5  16.7  225  22 11   6.3   3.5 |  -8.6  16.5  230  22 11   6.3   3.4
 20000  -6.7  19.9  230  21 11   6.3   3.5 |  -6.8  19.8  230  21 11   6.3   3.5
 19500  -5.7  21.7  230  21 11   6.3   3.5 |  -5.8  21.6  235  20 10   6.3   3.5
 19000  -4.8  23.4  230  21 11   6.6   3.6 |  -4.9  23.2  235  20 10   6.5   3.6
 18500  -3.8  25.2  230  21 11   6.6   3.6 |  -3.9  25.0  240  20 10   6.5   3.6
 18000  -2.8  27.0  230  21 11   6.7   3.7 |  -3.0  26.6  240  19 10   6.7   3.7
 17500  -1.8  28.8  230  20 11   6.8   3.7 |  -2.0  28.4  245  19 10   6.8   3.8
 17000  -0.9  30.4  235  20 10   6.8   3.7 |  -1.0  30.2  245  19 10   6.9   3.8
 16500   0.1  32.2  235  20 10   6.7   3.7 |   0.0  32.0  245  19 10   7.3   4.0
 16000   1.1  34.0  235  19 10   6.7   3.7 |   1.1  34.0  245  19 10   7.2   4.0
 15500   2.6  36.7  235  19 10   6.9   3.8 |   2.6  36.7  240  18  9   7.0   3.9
 15000   3.5  38.3  235  19 10   6.9   3.8 |   3.6  38.5  240  17  9   7.0   3.8
 14500   4.5  40.1  230  18  9   6.7   3.7 |   4.7  40.5  235  16  8   7.8   4.3
 14000   5.4  41.7  230  17  9   6.7   3.7 |   5.8  42.4  230  14  7   7.8   4.3
 13500   6.4  43.5  225  15  8   7.2   4.0 |   6.9  44.4  230  12  6   8.3   4.6
 13000   7.4  45.3  220  14  7   7.3   4.0 |   8.1  46.6  225  11  6   8.4   4.6
 12500   8.4  47.1  215  12  6   7.3   4.0 |   9.3  48.7  220  10  5   8.4   4.6
 12000   9.5  49.1  210  11  6   7.4   4.0 |  10.5  50.9  220   9  5   8.4   4.6
 11500  10.5  50.9  205  10  5   8.1   4.4 |  11.7  53.1  215   8  4   8.6   4.7
 11000  11.8  53.2  210   8  4   8.5   4.7 |  13.0  55.4  215   7  4   8.5   4.7
 10500  13.0  55.4  210   7  4   4.9   2.7 |  14.3  57.7  210   6  3   5.9   3.2
 10250  13.2  55.8  215   6  3   6.9   3.8 |  14.6  58.3  210   6  3   7.1   3.9
 10000  14.0  57.2  215   6  3  12.2   6.7 |  15.4  59.7  210   5  3  11.2   6.2
  9750  14.8  58.6  220   5  3  11.3   6.2 |  16.1  61.0  205   4  2  11.0   6.0
  9500  15.6  60.1  225   5  2   7.9   4.3 |  16.9  62.4  200   4  2   7.7   4.2
  9250  16.0  60.8  230   4  2   6.3   3.4 |  17.3  63.1  200   4  2   6.2   3.4
  9000  16.6  61.9  230   4  2   9.1   5.0 |  17.9  64.2  195   3  2   9.1   5.0
  8750  17.3  63.1  235   4  2   8.8   4.8 |  18.6  65.5  195   3  1   8.7   4.8
  8500  17.9  64.2  240   4  2   8.9   4.9 |  19.2  66.6  190   2  1   8.2   4.5
  8250  18.6  65.5  245   3  2   9.0   4.9 |  19.7  67.5  195   2  1   7.8   4.3
  8000  19.3  66.7  245   3  2  10.0   5.5 |  20.4  68.7  195   2  1   9.3   5.1
  7750  20.0  68.0  250   3  2  10.6   5.8 |  21.1  70.0  200   1  1  10.1   5.5
  7500  20.8  69.4  250   3  2  10.0   5.5 |  21.9  71.4  210   1  1  10.0   5.5
  7250  21.5  70.7  250   3  2  10.1   5.5 |  22.6  72.7  215   1  1  10.3   5.7
  7000  22.3  72.1  250   3  2   9.7   5.3 |  23.4  74.1  220   1  1   9.7   5.3
  6750  23.0  73.4  255   3  2  10.1   5.5 |  24.1  75.4  220   1  1   9.7   5.3
  6500  23.8  74.8  255   3  2  11.0   6.0 |  24.8  76.6  220   1  1  10.5   5.8
  6250  24.6  76.3  255   4  2  11.1   6.1 |  25.6  78.1  225   2  1  10.7   5.9
  6000  25.5  77.9  255   4  2  10.7   5.9 |  26.4  79.5  225   2  1  10.4   5.7
  5750  26.3  79.3  260   4  2  13.0   7.1 |  27.2  81.0  235   2  1  11.2   6.1
  5500  27.4  81.3  260   4  2  15.4   8.5 |  28.1  82.6  240   2  1  12.2   6.7
  5250  28.4  83.1  260   4  2  13.5   7.4 |  29.0  84.2  240   2  1  11.4   6.3
  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 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 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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