Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 241309
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0709 MDT Thursday, July 24, 2014

This forecast is for Thursday, July 24, 2014:

If the trigger temperature of 88.3 F/31.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 977 ft/min (5.0 m/s)
   Maximum height of thermals.................. 15585 ft MSL (10746 ft AGL)

Forecast maximum temperature................... 94.0 F/34.9 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ None
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................. 9040 ft MSL (4201 ft AGL)
Thermal soaring outlook for Friday 07/25....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:07:46 / 20:33:44 MDT
Total possible sunshine........... 14 hr 25 min 58 sec (865 min 58 sec)
Altitude of sun at 13:20:35 MDT... 70.61 degrees

Upper air data from rawinsonde observation taken on 07/24/2014 at 0600 MDT

Freezing level.................. 16505 ft MSL (11666 ft AGL)
Convective condensation level... 16162 ft MSL (11323 ft AGL)
Lifted condensation level....... 16118 ft MSL (11279 ft AGL)
Lifted index.................... -2.4
K index......................... +26.7

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  -71.2 -96.2   245   34   18   6.9   3.8   74.9 166.8    23.5      M    M
 45000  -62.2 -80.0   265   50   26   6.7   3.7   64.2 147.6    18.6      M    M
 40000  -51.9 -61.4   255   46   24   6.4   3.5   57.6 135.6    15.5      M    M
 38000  -47.1 -52.8   250   41   21   9.5   5.2   55.9 132.7    14.8      M    M
 36000  -41.5 -42.7   255   40   21   8.9   4.9   55.6 132.0    14.9      M    M
 34000  -36.3 -33.3   250   38   20   8.6   4.7   54.5 130.1    14.5      M    M
 32000  -31.9 -25.4   245   36   19   0.6   0.3   51.7 125.1    12.8      M    M
 30000  -27.8 -18.0   250   32   16   9.5   5.2   49.5 121.1    11.4      M    M
 29000  -25.1 -13.2   250   31   16   7.4   4.1   49.2 120.5    11.2      M    M
 28000  -22.9  -9.2   245   31   16   8.0   4.4   48.3 118.9    10.7      M    M
 27000  -20.4  -4.7   245   30   15   8.5   4.7   47.8 118.1    10.4      M    M
 26000  -17.8  -0.0   240   29   15   8.4   4.6   47.3 117.2    10.1      M    M
 25000  -15.4   4.3   235   27   14   7.8   4.3   46.8 116.2     9.8      M    M
 24000  -13.8   7.2   240   26   13   4.9   2.7   45.3 113.5     8.6      M    M
 23000  -13.6   7.5   245   25   13   6.8   3.7   42.0 107.7     5.9      M    M
 22000  -10.9  12.4   255   24   12   8.2   4.5   41.8 107.2     5.7      M    M
 21000  -10.2  13.6   210   22   12  -0.6  -0.4   39.2 102.5     3.5      M    M
 20000   -8.2  17.2   195   23   12   8.9   4.9   38.2 100.7     2.7      M    M
 19500   -6.9  19.6   195   23   12   8.9   4.9   38.0 100.4     2.5      M    M
 19000   -5.7  21.7   200   22   11   7.5   4.1   37.8 100.0     2.3      M    M
 18500   -4.7  23.5   200   20   10   7.1   3.9   37.3  99.1     1.8      M    M
 18000   -3.1  26.4   210   18    9   7.1   3.9   36.6  97.8     1.2      M    M
 17500   -2.1  28.2   215   17    9   7.1   3.9   36.2  97.1     0.8      M    M
 17000   -1.0  30.2   220   16    8   8.3   4.6   35.8  96.5     0.4      M    M
 16500    0.3  32.5   230   15    8   8.6   4.7   35.6  96.1     0.3      M    M
 16000    1.5  34.7   235   15    8   8.6   4.7   35.5  95.8     0.1      M    M
 15500    2.8  37.0   240   16    8   8.6   4.7   35.3  95.5    -0.1    959  4.9
 15000    4.1  39.4   245   16    8   8.6   4.7   35.1  95.2    -0.2    906  4.6
 14500    5.4  41.7   245   17    9   8.6   4.7   34.9  94.8    -0.4    852  4.3
 14000    6.7  44.1   245   18    9   8.5   4.7   34.7  94.5    -0.6    799  4.1
 13500    7.9  46.2   245   19   10   8.0   4.4   34.4  94.0    -0.9    749  3.8
 13000    9.0  48.2   245   20   10   8.1   4.4   34.1  93.5    -1.2    699  3.6
 12500   10.2  50.4   245   20   10   8.1   4.4   33.9  93.0    -1.5    649  3.3
 12000   11.4  52.5   245   21   11   8.1   4.4   33.7  92.6    -1.7    599  3.0
 11500   12.5  54.5   240   17    9   8.1   4.4   33.4  92.1    -2.1    550  2.8
 11000   13.7  56.7   235   13    7   8.1   4.4   33.1  91.6    -2.4    500  2.5
 10500   14.9  58.8   225   10    5   9.0   4.9   32.9  91.2    -2.6    449  2.3
 10250   15.6  60.1   225    9    5   9.0   4.9   32.8  91.1    -2.7    421  2.1
 10000   16.2  61.2   225    9    4   9.0   4.9   32.8  91.0    -2.8    394  2.0
  9750   16.9  62.4   230    8    4   9.0   4.9   32.7  90.9    -2.8    367  1.9
  9500   17.6  63.7   230    7    4   9.0   4.9   32.7  90.9    -2.9    340  1.7
  9250   18.2  64.8   230    7    3   9.0   4.9   32.7  90.8    -3.0    313  1.6
  9000   18.9  66.0   235    6    3   9.0   4.9   32.6  90.7    -3.0    285  1.4
  8750   19.6  67.3   235    6    3   9.0   4.9   32.6  90.6    -3.1    258  1.3
  8500   20.2  68.4   235    6    3   9.0   4.9   32.5  90.5    -3.2    231  1.2
  8250   20.9  69.6   230    6    3   9.0   4.9   32.4  90.4    -3.2    204  1.0
  8000   21.5  70.7   230    6    3   9.0   4.9   32.4  90.3    -3.3    177  0.9
  7750   22.2  72.0   215    8    4   9.0   4.9   32.3  90.2    -3.4    149  0.8
  7500   22.9  73.2   205   10    5   9.0   4.9   32.3  90.1    -3.5    122  0.6
  7250   23.5  74.3   200   12    6   9.0   4.9   32.2  90.0    -3.5     95  0.5
  7000   24.2  75.6   195   14    7   9.0   4.9   32.1  89.9    -3.6     68  0.3
  6750   24.8  76.6   185   16    8   9.0   5.0   32.1  89.7    -3.7     41  0.2
  6500   25.5  77.9   175   19   10   9.0   4.9   32.0  89.6    -3.8     13  0.1
  6250   26.1  79.0   165   22   11   7.4   4.0   31.9  89.4    -3.9      M    M
  6000   26.6  79.9   160   25   13   6.3   3.4   31.7  89.0    -4.2      M    M
  5750   27.1  80.8   160   24   12   6.6   3.6   31.4  88.5    -4.5      M    M
  5500   27.5  81.5   155   21   11   6.5   3.5   31.2  88.1    -4.7      M    M
  5250   28.0  82.4   155   18   10   6.7   3.7   30.9  87.7    -5.0      M    M
  5000   28.5  83.3   150   16    8   5.9   3.2   30.7  87.2    -5.3      M    M

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

           07/24/2014 at 0900 MDT          |       07/24/2014 at 1200 MDT
                                           |
K index... +32.7  LI... -3.1               | K index... +29.1  LI... -3.1
CAPE... +369.7  CIN... -43.1               | CAPE... +646.3  CIN... -2.3
                                           |
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 -68.0 -90.4  255  36 19   3.0   1.6 | -68.2 -90.8  260  39 20   2.3   1.2
 45000 -60.9 -77.6  260  46 24   7.0   3.8 | -61.8 -79.2  260  53 27   7.0   3.8
 40000 -50.4 -58.7  270  50 26   7.4   4.0 | -51.0 -59.8  260  53 27   8.2   4.5
 38000 -46.0 -50.8  265  45 23   7.4   4.0 | -46.1 -51.0  260  47 24   8.2   4.5
 36000 -41.6 -42.9  265  41 21   7.5   4.1 | -41.2 -42.2  255  42 21   8.0   4.4
 34000 -37.0 -34.6  265  37 19   7.6   4.2 | -36.4 -33.5  250  36 19   7.9   4.3
 32000 -31.9 -25.4  260  31 16   7.7   4.3 | -31.1 -24.0  245  30 16   8.4   4.6
 30000 -27.5 -17.5  260  24 12   7.4   4.1 | -26.7 -16.1  240  24 12   7.5   4.1
 29000 -25.3 -13.5  255  20 11   7.5   4.1 | -24.5 -12.1  240  21 11   7.5   4.1
 28000 -23.1  -9.6  255  19 10   7.4   4.1 | -22.3  -8.1  235  19 10   6.9   3.8
 27000 -20.9  -5.6  255  19 10   7.5   4.1 | -20.3  -4.5  235  18  9   6.9   3.8
 26000 -18.7  -1.7  250  20 10   7.5   4.1 | -18.3  -0.9  235  18  9   6.9   3.8
 25000 -16.6   2.1  250  20 10   6.3   3.5 | -16.2   2.8  235  17  9   6.6   3.6
 24000 -14.9   5.2  240  22 11   5.9   3.3 | -14.3   6.3  235  19 10   6.4   3.5
 23000 -13.1   8.4  235  23 12   5.9   3.3 | -12.4   9.7  235  20 10   6.5   3.5
 22000 -11.4  11.5  230  25 13   5.9   3.2 | -10.6  12.9  230  21 11   6.4   3.5
 21000  -9.7  14.5  225  26 14   5.8   3.2 |  -8.7  16.3  230  22 11   6.4   3.5
 20000  -8.0  17.6  220  28 14   5.9   3.2 |  -6.8  19.8  230  22 11   6.4   3.5
 19500  -7.2  19.0  215  28 15   5.9   3.3 |  -5.9  21.4  230  23 12   6.4   3.5
 19000  -6.3  20.7  215  28 15   6.1   3.3 |  -5.0  23.0  230  22 11   6.2   3.4
 18500  -5.0  23.0  210  28 14   6.3   3.5 |  -3.6  25.5  235  21 11   6.2   3.4
 18000  -4.0  24.8  210  27 14   7.6   4.2 |  -2.7  27.1  235  20 11   6.4   3.5
 17500  -2.9  26.8  210  27 14   7.6   4.2 |  -1.8  28.8  235  20 10   6.4   3.5
 17000  -1.9  28.6  210  26 13   7.0   3.8 |  -0.8  30.6  235  20 10   6.7   3.7
 16500  -0.9  30.4  215  25 13   6.9   3.8 |   0.1  32.2  235  19 10   6.8   3.7
 16000   0.1  32.2  215  25 13   7.6   4.1 |   1.1  34.0  230  18  9   6.7   3.7
 15500   1.3  34.3  220  25 13   8.7   4.8 |   2.0  35.6  230  18  9   6.5   3.6
 15000   2.6  36.7  220  24 13   8.7   4.8 |   2.9  37.2  230  17  9   6.5   3.6
 14500   3.9  39.0  225  24 12   8.6   4.7 |   3.9  39.0  225  17  9   6.5   3.6
 14000   5.1  41.2  225  23 12   8.7   4.8 |   4.8  40.6  225  17  9   6.5   3.6
 13500   6.3  43.3  225  22 11   7.9   4.4 |   5.8  42.4  225  17  9   7.5   4.1
 13000   7.5  45.5  230  21 11   7.9   4.3 |   6.8  44.2  225  17  9   7.6   4.2
 12500   8.6  47.5  230  20 10   8.4   4.6 |   7.9  46.2  225  17  9   8.4   4.6
 12000   9.9  49.8  230  19 10   8.5   4.7 |   9.2  48.6  220  18  9   8.7   4.8
 11500  11.1  52.0  230  18  9   8.7   4.8 |  10.4  50.7  220  18  9   9.5   5.2
 11000  12.4  54.3  230  16  8   8.8   4.8 |  11.9  53.4  215  18 10   9.8   5.4
 10500  13.7  56.7  230  15  8   7.2   4.0 |  13.2  55.8  215  19 10   4.7   2.6
 10250  14.1  57.4  230  14  7   7.7   4.2 |  13.5  56.3  215  19 10   6.5   3.6
 10000  14.8  58.6  230  14  7   9.4   5.2 |  14.3  57.7  215  19 10  13.1   7.2
  9750  15.5  59.9  225  13  7   8.9   4.9 |  15.2  59.4  210  18  9  11.6   6.4
  9500  16.1  61.0  225  12  6   8.6   4.7 |  16.0  60.8  210  18  9   9.3   5.1
  9250  16.7  62.1  225  12  6   8.3   4.5 |  16.5  61.7  205  18  9   7.8   4.3
  9000  17.3  63.1  225  11  6   8.4   4.6 |  17.2  63.0  205  17  9  10.3   5.7
  8750  17.9  64.2  220  11  6   8.3   4.6 |  18.0  64.4  200  17  9  10.8   5.9
  8500  18.5  65.3  220  10  5   8.1   4.5 |  18.7  65.7  200  16  8   9.7   5.3
  8250  19.1  66.4  215  10  5   8.0   4.4 |  19.4  66.9  195  16  8   9.0   4.9
  8000  19.7  67.5  215  10  5   8.1   4.5 |  20.1  68.2  195  16  8   9.5   5.2
  7750  20.2  68.4  210   9  5   7.2   3.9 |  20.8  69.4  195  15  8   9.9   5.4
  7500  20.7  69.3  200   9  4   5.5   3.0 |  21.5  70.7  190  15  8  10.1   5.5
  7250  21.0  69.8  190   8  4   4.7   2.6 |  22.2  72.0  190  15  8  10.0   5.5
  7000  21.4  70.5  180   9  4   6.0   3.3 |  23.0  73.4  190  15  8  10.4   5.7
  6750  21.8  71.2  165   9  5   3.2   1.8 |  23.7  74.7  190  15  7  10.6   5.8
  6500  21.8  71.2  155   9  5  -0.4  -0.2 |  24.5  76.1  190  14  7  10.4   5.7
  6250  21.8  71.2  140   9  5  -0.3  -0.2 |  25.3  77.5  190  14  7   9.9   5.4
  6000  21.8  71.2  130  10  5   1.0   0.6 |  26.1  79.0  190  13  7  11.4   6.3
  5750  21.9  71.4  125  10  5   4.8   2.6 |  27.1  80.8  190  13  7  18.3  10.0
  5500  22.2  72.0  120   9  5   6.6   3.6 |  28.7  83.7  190  12  6  25.0  13.7
  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

           07/24/2014 at 1500 MDT          |       07/24/2014 at 1800 MDT
                                           |
K index... +31.2  LI... -2.5               | K index... +28.9  LI... -3.1
CAPE... +390.2  CIN... -8.1                | CAPE... +456.3  CIN... -16.5
                                           |
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 -68.2 -90.8  260  40 21   1.8   1.0 | -67.7 -89.9  250  40 21   1.6   0.9
 45000 -62.6 -80.7  260  57 30   7.1   3.9 | -62.5 -80.5  255  56 29   7.0   3.9
 40000 -51.2 -60.2  260  51 26   8.1   4.4 | -51.1 -60.0  260  50 26   7.9   4.3
 38000 -46.3 -51.3  255  45 23   8.1   4.4 | -46.4 -51.5  260  45 23   7.9   4.3
 36000 -41.4 -42.5  255  40 21   8.3   4.5 | -41.6 -42.9  260  40 20   8.4   4.6
 34000 -36.5 -33.7  250  37 19   8.3   4.6 | -36.5 -33.7  255  38 19   8.5   4.7
 32000 -31.5 -24.7  240  35 18   8.8   4.8 | -31.4 -24.5  250  36 18   8.8   4.8
 30000 -26.9 -16.4  240  32 16   7.8   4.3 | -26.9 -16.4  250  33 17   7.5   4.1
 29000 -24.0 -11.2  245  30 15   7.8   4.3 | -24.1 -11.4  255  31 16   7.5   4.1
 28000 -21.8  -7.2  245  28 14   7.2   4.0 | -22.0  -7.6  255  30 15   6.9   3.8
 27000 -19.7  -3.5  245  26 13   7.2   4.0 | -20.0  -4.0  255  30 15   6.9   3.8
 26000 -17.6   0.3  240  24 12   7.3   4.0 | -17.9  -0.2  255  29 15   6.9   3.8
 25000 -15.5   4.1  240  22 11   5.9   3.3 | -15.9   3.4  260  29 15   6.4   3.5
 24000 -13.8   7.2  240  21 11   5.8   3.2 | -14.1   6.6  260  26 13   6.4   3.5
 23000 -12.1  10.2  245  21 11   5.8   3.2 | -12.2  10.0  265  23 12   6.5   3.6
 22000 -10.4  13.3  245  20 10   6.2   3.4 | -10.4  13.3  270  21 11   5.8   3.2
 21000  -8.6  16.5  240  20 10   6.3   3.4 |  -8.8  16.2  275  20 10   5.7   3.1
 20000  -6.8  19.8  240  20 10   6.3   3.4 |  -7.1  19.2  285  20 10   5.7   3.1
 19500  -5.8  21.6  240  20 10   6.4   3.5 |  -6.3  20.7  285  20 10   6.3   3.5
 19000  -4.9  23.2  240  19 10   6.6   3.6 |  -5.2  22.6  285  20 10   7.7   4.2
 18500  -3.9  25.0  235  19 10   6.6   3.6 |  -4.0  24.8  290  20 10   7.7   4.2
 18000  -3.0  26.6  235  19 10   6.2   3.4 |  -2.9  26.8  290  20 11   7.3   4.0
 17500  -2.1  28.2  235  18  9   6.1   3.4 |  -1.8  28.8  285  20 10   7.2   4.0
 17000  -1.2  29.8  235  17  9   6.2   3.4 |  -0.8  30.6  285  20 10   7.2   4.0
 16500  -0.3  31.5  235  17  9   6.3   3.5 |   0.3  32.5  280  19 10   7.1   3.9
 16000   0.6  33.1  235  17  9   6.4   3.5 |   1.3  34.3  275  18  9   7.1   3.9
 15500   1.5  34.7  235  16  8   6.5   3.5 |   2.3  36.1  270  17  9   6.6   3.6
 15000   2.4  36.3  235  16  8   6.5   3.6 |   3.2  37.8  265  17  9   6.7   3.7
 14500   3.3  37.9  235  16  8   6.7   3.7 |   4.2  39.6  260  16  8   6.8   3.7
 14000   4.7  40.5  235  16  8   6.7   3.7 |   5.1  41.2  255  15  8   6.8   3.8
 13500   5.8  42.4  235  16  8   8.1   4.4 |   6.6  43.9  245  14  7   7.0   3.9
 13000   6.9  44.4  235  16  8   8.0   4.4 |   7.5  45.5  240  13  6   7.0   3.8
 12500   8.1  46.6  230  15  8   9.2   5.0 |   8.6  47.5  235  11  6   9.0   4.9
 12000   9.4  48.9  230  15  8   9.3   5.1 |  10.0  50.0  230  11  6   9.3   5.1
 11500  10.8  51.4  230  15  8   9.6   5.3 |  11.3  52.3  230  10  5   9.6   5.3
 11000  12.2  54.0  230  15  8  10.1   5.5 |  12.7  54.9  220   9  5  10.1   5.5
 10500  13.4  56.1  225  15  8   5.4   3.0 |  13.9  57.0  215   8  4   5.2   2.8
 10250  13.9  57.0  225  14  7   9.5   5.2 |  14.4  57.9  210   8  4   8.2   4.5
 10000  14.8  58.6  225  14  7  12.4   6.8 |  15.1  59.2  205   8  4  11.3   6.2
  9750  15.6  60.1  220  14  7  11.1   6.1 |  15.9  60.6  200   8  4  10.3   5.7
  9500  16.3  61.3  220  14  7   8.1   4.5 |  16.6  61.9  195   8  4   7.2   4.0
  9250  16.9  62.4  220  13  7   8.2   4.5 |  17.0  62.6  190   8  4   7.2   3.9
  9000  17.6  63.7  215  12  6  10.6   5.8 |  17.7  63.9  185   8  4   9.8   5.4
  8750  18.4  65.1  215  12  6   9.8   5.4 |  18.4  65.1  180   9  4   9.2   5.1
  8500  19.0  66.2  215  11  6   8.8   4.8 |  19.0  66.2  175   9  5   8.7   4.8
  8250  19.7  67.5  210  11  5   8.5   4.7 |  19.6  67.3  170   9  5   8.4   4.6
  8000  20.3  68.5  210  10  5   9.3   5.1 |  20.3  68.5  165   9  5   9.4   5.2
  7750  21.0  69.8  205   9  5   9.7   5.3 |  21.0  69.8  165   9  5   9.8   5.4
  7500  21.7  71.1  205   9  5   9.6   5.3 |  21.7  71.1  160   9  5   9.4   5.1
  7250  22.4  72.3  205   9  5   9.6   5.3 |  22.4  72.3  160   9  5   9.3   5.1
  7000  23.1  73.6  205   9  4   9.7   5.3 |  23.1  73.6  160   9  5   9.6   5.3
  6750  23.9  75.0  205   8  4  10.0   5.5 |  23.8  74.8  160   9  5  10.1   5.5
  6500  24.6  76.3  205   8  4  10.0   5.5 |  24.6  76.3  160   9  4  10.1   5.5
  6250  25.4  77.7  205   8  4  10.2   5.6 |  25.3  77.5  160   8  4  10.0   5.5
  6000  26.1  79.0  205   8  4   9.4   5.2 |  26.1  79.0  160   8  4  10.2   5.6
  5750  26.8  80.2  205   7  4   8.6   4.7 |  26.7  80.1  160   7  4   9.2   5.1
  5500  27.4  81.3  205   7  3   8.8   4.8 |  27.4  81.3  160   7  4   8.2   4.5
  5250  28.0  82.4  205   6  3   8.6   4.7 |  28.0  82.4  155   7  3   9.0   4.9
  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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