Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 261229
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0629 MDT Friday, August 26, 2016

This forecast is for Friday, August 26, 2016:

If the trigger temperature of 68.4 F/20.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 894 ft/min (4.5 m/s)
   Maximum height of thermals.................. 15642 ft MSL (10803 ft AGL)

Forecast maximum temperature................... 80.0 F/27.1 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11881 ft MSL (7042 ft AGL)
Thermal soaring outlook for Saturday 08/27..... Good

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

Remarks...

Sunrise/Sunset.................... 06:37:53 / 19:54:14 MDT
Total possible sunshine........... 13 hr 16 min 20 sec (796 min 20 sec)
Altitude of sun at 13:15:39 MDT... 60.93 degrees

Upper air data from rawinsonde observation taken on 08/26/2016 at 0600 MDT

Freezing level.................. 13348 ft MSL (8509 ft AGL)
Convective condensation level... 13234 ft MSL (8395 ft AGL)
Lifted condensation level....... 13798 ft MSL (8959 ft AGL)
Lifted index.................... -3.5
K index......................... +23.0

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  -61.3 -78.3   240   41   21   0.1   0.1   95.7 204.3    39.7      M    M
 45000  -53.0 -63.4   245   33   17   5.6   3.1   83.8 182.8    35.2      M    M
 40000  -56.8 -70.2   240   45   23   5.3   2.9   55.1 131.1    18.7      M    M
 38000  -54.4 -65.9   250   39   20   1.0   0.6   50.0 122.0    15.8      M    M
 36000  -52.6 -62.7   240   46   24   6.3   3.5   44.1 111.4    12.2      M    M
 34000  -48.0 -54.4   235   52   27   8.5   4.7   42.3 108.2    11.2      M    M
 32000  -42.2 -44.0   245   47   24   7.4   4.1   41.2 106.1    10.7      M    M
 30000  -37.8 -36.0   250   42   22  10.0   5.5   39.3 102.8     9.5      M    M
 29000  -35.3 -31.5   250   41   21   9.9   5.4   38.8 101.9     9.3      M    M
 28000  -32.6 -26.7   250   41   21   9.7   5.3   38.5 101.4     9.1      M    M
 27000  -30.1 -22.2   255   40   21   6.8   3.8   38.0 100.4     8.8      M    M
 26000  -27.4 -17.3   255   40   21   8.2   4.5   37.6  99.7     8.7      M    M
 25000  -25.1 -13.2   250   32   16   8.7   4.8   37.0  98.5     8.2      M    M
 24000  -23.6 -10.5   245   28   14   6.6   3.6   35.3  95.5     6.9      M    M
 23000  -21.5  -6.7   255   21   11   5.9   3.2   34.3  93.8     6.1      M    M
 22000  -19.5  -3.1   285   16    8   6.1   3.3   33.1  91.6     5.2      M    M
 21000  -17.4   0.7   270   16    8   7.6   4.2   32.2  89.9     4.4      M    M
 20000  -15.1   4.8   250   18    9   7.8   4.3   31.5  88.7     3.9      M    M
 19500  -13.9   7.0   250   16    8   7.4   4.0   31.2  88.1     3.7      M    M
 19000  -12.9   8.8   245   13    7   6.6   3.6   30.6  87.1     3.2      M    M
 18500  -12.0  10.4   255    9    5   3.5   1.9   30.0  85.9     2.7      M    M
 18000  -11.9  10.6   275    5    2   4.4   2.4   28.5  83.2     1.3      M    M
 17500  -10.1  13.8   295    6    3   8.5   4.6   28.0  82.5     1.3      M    M
 17000   -8.9  16.0   295    7    4   8.3   4.5   27.8  82.0     0.7      M    M
 16500   -7.7  18.1   295    9    5   8.3   4.6   27.5  81.5     0.4      M    M
 16000   -6.5  20.3   295   10    5   8.4   4.6   27.3  81.2     0.1      M    M
 15500   -5.3  22.5   300   10    5   8.6   4.7   27.1  80.7    -0.1    869  4.4
 15000   -4.0  24.8   305   10    5   8.6   4.7   26.9  80.4    -0.3    816  4.1
 14500   -2.7  27.1   310   10    5   8.6   4.7   26.7  80.0    -0.5    763  3.9
 14000   -1.5  29.3   315   10    5   8.6   4.7   26.5  79.7    -0.6    710  3.6
 13500   -0.2  31.6   315   11    5   8.8   4.8   26.3  79.4    -0.9    659  3.3
 13000    0.6  33.1   315   11    6   5.1   2.8   25.8  78.5    -1.5    618  3.1
 12500    1.5  34.7   290   11    6   6.0   3.3   25.2  77.4    -2.1    577  2.9
 12000    2.2  36.0   270   13    7   4.1   2.3   24.5  76.0    -2.8    541  2.7
 11500    2.7  36.9   260   12    6   5.0   2.7   23.6  74.4    -3.8    510  2.6
 11000    3.6  38.5   245   11    6   6.0   3.3   23.0  73.3    -4.4    470  2.4
 10500    4.6  40.3   245   10    5   8.0   4.4   22.5  72.5    -4.9    426  2.2
 10250    5.2  41.4   245   10    5   7.6   4.2   22.4  72.3    -5.0    400  2.0
 10000    5.7  42.3   240    9    4   7.1   3.9   22.2  71.9    -5.2    377  1.9
  9750    6.3  43.3   240    8    4   7.2   4.0   22.0  71.5    -5.5    353  1.8
  9500    6.8  44.2   235    7    3   7.2   4.0   21.8  71.2    -5.7    329  1.7
  9250    7.3  45.1   230    6    3   7.2   4.0   21.6  70.8    -5.9    306  1.6
  9000    7.9  46.2   220    5    3   7.3   4.0   21.4  70.5    -6.0    282  1.4
  8750    8.4  47.1   195    6    3   7.0   3.9   21.2  70.1    -6.3    259  1.3
  8500    8.9  48.0   180    8    4   6.6   3.6   20.9  69.7    -6.5    237  1.2
  8250    9.4  48.9   170   11    6   6.6   3.6   20.7  69.3    -6.8    215  1.1
  8000    9.9  49.8   165   14    7   6.6   3.6   20.5  68.8    -7.0    194  1.0
  7750   10.3  50.5   165   14    7   6.6   3.6   20.2  68.4    -7.3    172  0.9
  7500   10.8  51.4   165   14    7   6.6   3.6   20.0  67.9    -7.6    151  0.8
  7250   11.3  52.3   160   14    7   6.6   3.6   19.7  67.5    -7.9    129  0.7
  7000   11.8  53.2   160   14    7   6.6   3.6   19.5  67.1    -8.1    107  0.5
  6750   12.2  54.0   155   14    7   6.4   3.5   19.2  66.6    -8.4     86  0.4
  6500   12.7  54.9   150   15    8   7.1   3.9   19.0  66.2    -8.7     64  0.3
  6250   13.2  55.8   145   15    8   4.5   2.5   18.8  65.8    -9.0     43  0.2
  6000   13.3  55.9   140   16    8   2.1   1.2   18.2  64.8    -9.6     31  0.2
  5750   13.5  56.3   135   15    8   1.4   0.8   17.6  63.8   -10.2     19  0.1
  5500   13.6  56.5   130   13    7   7.2   3.9   17.1  62.8   -10.8      6  0.0
  5250   14.3  57.7   125   12    6   5.7   3.1   17.1  62.7   -10.8      M    M
  5000   13.8  56.8   115   10    5 -19.4 -10.6   15.9  60.7   -12.1      M    M

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

           08/26/2016 at 0900 MDT          |       08/26/2016 at 1200 MDT
                                           |
K index... +24.2  LI... +270.5             | K index... +16.2  LI... +269.3
CAPE... +479.0  CIN... -34.4               | CAPE... +706.1  CIN... -17.7
                                           |
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 -57.5 -71.5  260  28 15   2.3   1.2 | -57.8 -72.0  255  30 15   1.7   1.0
 45000 -54.6 -66.3  260  41 21   0.1   0.0 | -55.6 -68.1  260  41 21   0.2   0.1
 40000 -54.5 -66.1  265  41 21   0.4   0.2 | -55.3 -67.5  275  41 21   1.1   0.6
 38000 -52.7 -62.9  260  39 20   3.3   1.8 | -53.2 -63.8  280  34 18   3.7   2.0
 36000 -50.7 -59.3  260  37 19   3.3   1.8 | -51.0 -59.8  295  28 14   3.7   2.0
 34000 -47.6 -53.7  255  35 18   6.9   3.8 | -47.4 -53.3  305  25 13   7.8   4.3
 32000 -43.0 -45.4  260  33 17   6.9   3.8 | -42.7 -44.9  305  24 13   7.8   4.3
 30000 -38.2 -36.8  260  31 16   8.6   4.7 | -37.3 -35.1  300  24 12   8.2   4.5
 29000 -35.6 -32.1  265  29 15   8.6   4.7 | -34.8 -30.6  295  23 12   8.2   4.5
 28000 -33.1 -27.6  265  28 15   8.7   4.8 | -32.3 -26.1  290  23 12   8.3   4.5
 27000 -30.6 -23.1  265  27 14   8.2   4.5 | -30.0 -22.0  290  22 12   7.8   4.3
 26000 -28.1 -18.6  265  26 13   8.2   4.5 | -27.6 -17.7  285  21 11   7.8   4.3
 25000 -25.7 -14.3  265  25 13   8.1   4.5 | -25.3 -13.5  285  20 10   7.9   4.3
 24000 -23.3  -9.9  270  23 12   7.6   4.2 | -23.0  -9.4  285  19 10   7.2   3.9
 23000 -21.0  -5.8  270  21 11   7.6   4.2 | -20.9  -5.6  285  19 10   7.2   3.9
 22000 -18.7  -1.7  270  19 10   7.6   4.2 | -18.7  -1.7  280  18  9   7.3   4.0
 21000 -16.7   1.9  270  18  9   6.2   3.4 | -16.7   1.9  285  18  9   6.3   3.5
 20000 -14.9   5.2  270  18  9   6.3   3.5 | -14.8   5.4  290  18  9   6.3   3.5
 19500 -14.0   6.8  270  17  9   6.4   3.5 | -13.9   7.0  290  18  9   6.3   3.5
 19000 -13.1   8.4  270  17  9   6.3   3.5 | -12.9   8.8  290  18  9   6.4   3.5
 18500 -11.9  10.6  280  15  8   5.9   3.3 | -12.0  10.4  295  18  9   6.5   3.6
 18000 -11.0  12.2  290  13  7   6.5   3.6 | -11.0  12.2  295  18  9   6.5   3.6
 17500  -9.9  14.2  295  13  7   7.6   4.2 |  -9.9  14.2  300  18  9   7.6   4.2
 17000  -8.8  16.2  305  13  7   7.5   4.1 |  -8.8  16.2  300  18  9   7.5   4.1
 16500  -7.6  18.3  310  13  7   8.2   4.5 |  -7.7  18.1  300  17  9   8.0   4.4
 16000  -6.5  20.3  315  13  7   8.1   4.5 |  -6.5  20.3  305  17  9   8.3   4.6
 15500  -5.3  22.5  315  12  6   8.2   4.5 |  -5.3  22.5  305  16  8   8.5   4.7
 15000  -4.1  24.6  320  12  6   8.3   4.5 |  -4.0  24.8  305  16  8   8.8   4.8
 14500  -2.9  26.8  325  12  6   8.1   4.5 |  -2.1  28.2  310  14  7   8.6   4.7
 14000  -1.7  28.9  325  11  6   8.0   4.4 |  -0.9  30.4  310  13  7   8.5   4.7
 13500  -0.6  30.9  325  11  6   7.8   4.3 |   0.3  32.5  310  12  6   8.2   4.5
 13000   0.4  32.7  320  10  5   6.6   3.6 |   1.3  34.3  310  11  6   7.6   4.2
 12500   1.3  34.3  315  10  5   6.7   3.7 |   2.4  36.3  305   9  5   7.5   4.1
 12000   2.2  36.0  305   9  5   6.2   3.4 |   3.4  38.1  300   8  4   7.0   3.9
 11500   3.1  37.6  300   9  4   6.2   3.4 |   4.4  39.9  290   7  4   6.9   3.8
 11000   3.9  39.0  290   8  4   6.0   3.3 |   5.3  41.5  280   7  4   6.0   3.3
 10500   4.8  40.6  280   8  4   5.5   3.0 |   6.1  43.0  270   7  4   3.5   1.9
 10250   5.1  41.2  275   8  4   4.1   2.2 |   6.3  43.3  265   7  4   4.8   2.6
 10000   5.5  41.9  270   8  4   7.5   4.1 |   6.9  44.4  260   7  4   9.3   5.1
  9750   6.2  43.2  265   8  4  10.6   5.8 |   7.5  45.5  255   7  4   8.9   4.9
  9500   6.9  44.4  260   8  4   9.2   5.0 |   8.1  46.6  255   7  4   7.0   3.8
  9250   7.4  45.3  260   7  4   6.0   3.3 |   8.5  47.3  250   7  4   4.5   2.5
  9000   7.8  46.0  255   7  4   5.9   3.3 |   8.8  47.8  245   7  3   6.5   3.6
  8750   8.3  46.9  250   6  3   8.2   4.5 |   9.4  48.9  235   6  3   7.5   4.1
  8500   8.8  47.8  250   6  3   7.1   3.9 |   9.9  49.8  220   6  3   7.2   4.0
  8250   9.3  48.7  245   5  3   5.9   3.2 |  10.3  50.5  215   6  3   6.9   3.8
  8000   9.7  49.5  240   5  2   5.9   3.2 |  10.8  51.4  205   6  3   8.2   4.5
  7750  10.1  50.2  230   4  2   6.9   3.8 |  11.4  52.5  205   6  3   9.7   5.3
  7500  10.6  51.1  220   4  2   6.6   3.6 |  12.1  53.8  200   6  3   9.9   5.4
  7250  11.1  52.0  210   5  2   6.0   3.3 |  12.9  55.2  200   6  3  10.0   5.5
  7000  11.5  52.7  200   5  3   6.2   3.4 |  13.6  56.5  200   6  3  10.5   5.8
  6750  12.0  53.6  195   6  3   6.7   3.7 |  14.4  57.9  200   6  3  11.2   6.1
  6500  12.5  54.5  185   6  3   6.1   3.3 |  15.3  59.5  200   6  3  10.9   6.0
  6250  12.9  55.2  185   6  3   6.2   3.4 |  16.1  61.0  200   6  3  11.2   6.1
  6000  13.2  55.8  180   6  3   3.9   2.1 |  16.9  62.4  200   6  3  10.2   5.6
  5750  13.5  56.3  170   5  3   9.0   4.9 |  17.7  63.9  200   5  3  12.6   6.9
  5500  14.8  58.6  175   5  3  24.7  13.5 |  18.8  65.8  205   5  3  16.0   8.8
  5250     M     M    M   M  M     M     M |  19.9  67.8  205   5  3  13.4   7.3
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/26/2016 at 1500 MDT          |       08/26/2016 at 1800 MDT
                                           |
K index... +18.8  LI... +269.1             | K index... +28.2  LI... +269.8
CAPE... +931.0  CIN... -12.5               | CAPE... +717.5  CIN... -13.0
                                           |
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 -58.2 -72.8  250  33 17   1.6   0.9 | -58.3 -72.9  255  33 17   0.6   0.3
 45000 -56.5 -69.7  260  43 22  -0.7  -0.4 | -57.6 -71.7  260  44 23  -0.4  -0.2
 40000 -57.5 -71.5  275  43 22   1.7   0.9 | -58.2 -72.8  265  45 23   2.5   1.4
 38000 -54.3 -65.7  275  38 19   5.5   3.0 | -54.7 -66.5  265  42 22   5.9   3.2
 36000 -51.0 -59.8  280  33 17   5.5   3.0 | -51.1 -60.0  270  39 20   5.9   3.2
 34000 -46.8 -52.2  280  31 16   8.2   4.5 | -46.6 -51.9  275  36 18   8.5   4.7
 32000 -41.9 -43.4  280  32 16   8.2   4.5 | -41.5 -42.7  280  32 16   8.5   4.7
 30000 -36.2 -33.2  280  31 16   8.5   4.7 | -35.6 -32.1  280  28 15   8.8   4.8
 29000 -33.7 -28.7  280  30 16   8.5   4.7 | -33.0 -27.4  280  27 14   8.8   4.8
 28000 -31.1 -24.0  285  30 15   8.5   4.7 | -30.4 -22.7  280  26 13   8.7   4.8
 27000 -28.7 -19.7  285  28 15   8.0   4.4 | -28.1 -18.6  280  25 13   7.7   4.2
 26000 -26.3 -15.3  285  27 14   8.0   4.4 | -25.8 -14.4  280  25 13   7.7   4.2
 25000 -23.9 -11.0  285  26 13   8.0   4.4 | -23.5 -10.3  280  25 13   7.7   4.2
 24000 -21.6  -6.9  285  24 12   7.3   4.0 | -21.3  -6.3  280  24 12   7.3   4.0
 23000 -19.5  -3.1  285  21 11   7.3   4.0 | -19.2  -2.6  280  24 12   7.3   4.0
 22000 -17.3   0.9  285  19 10   7.4   4.1 | -17.0   1.4  280  23 12   7.4   4.1
 21000 -15.4   4.3  285  18  9   5.9   3.2 | -15.1   4.8  275  22 11   6.1   3.3
 20000 -13.6   7.5  285  18  9   5.9   3.2 | -13.3   8.1  275  22 11   6.1   3.3
 19500 -12.7   9.1  285  18  9   5.9   3.2 | -12.4   9.7  275  21 11   6.1   3.3
 19000 -11.9  10.6  285  18  9   5.5   3.0 | -11.5  11.3  270  21 11   6.3   3.5
 18500 -11.1  12.0  295  18  9   5.3   2.9 | -10.5  13.1  270  20 10   6.4   3.5
 18000 -10.4  13.3  300  18  9   5.4   3.0 |  -9.5  14.9  265  19 10   6.4   3.5
 17500  -9.4  15.1  305  18  9   7.9   4.3 |  -8.5  16.7  265  18  9   7.3   4.0
 17000  -8.3  17.1  310  17  9   7.8   4.3 |  -7.5  18.5  260  18  9   7.3   4.0
 16500  -7.2  19.0  310  17  9   8.0   4.4 |  -6.4  20.5  260  18  9   7.5   4.1
 16000  -6.0  21.2  315  15  8   8.1   4.4 |  -5.3  22.5  260  18  9   7.6   4.1
 15500  -4.8  23.4  315  14  7   8.2   4.5 |  -4.3  24.3  255  18  9   7.8   4.3
 15000  -3.5  25.7  315  13  7   8.3   4.6 |  -3.1  26.4  255  17  9   8.2   4.5
 14500  -1.6  29.1  305  11  6   8.3   4.5 |  -1.4  29.5  255  15  8   8.1   4.4
 14000  -0.4  31.3  295  10  5   8.3   4.6 |  -0.2  31.6  250  15  8   8.1   4.4
 13500   0.8  33.4  290   9  5   8.4   4.6 |   0.9  33.6  250  14  7   8.2   4.5
 13000   2.0  35.6  275   9  5   8.5   4.7 |   2.1  35.8  250  13  7   8.3   4.6
 12500   3.2  37.8  265   9  5   8.7   4.7 |   3.3  37.9  250  12  6   8.4   4.6
 12000   4.3  39.7  255   9  5   8.8   4.8 |   4.5  40.1  250  12  6   8.5   4.7
 11500   5.5  41.9  245   9  5   8.9   4.9 |   5.7  42.3  250  11  6   8.7   4.8
 11000   6.7  44.1  240  10  5   8.7   4.7 |   7.1  44.8  250  11  6   9.3   5.1
 10500   8.0  46.4  235  10  5   4.8   2.7 |   8.4  47.1  245  10  5   5.7   3.1
 10250   8.2  46.8  235  10  5   5.1   2.8 |   8.7  47.7  245  10  5   6.0   3.3
 10000   8.8  47.8  230   9  5  10.5   5.8 |   9.4  48.9  245   9  5  11.0   6.0
  9750   9.4  48.9  230   9  5   9.6   5.3 |  10.2  50.4  245   9  5  10.0   5.5
  9500  10.1  50.2  225   9  5   8.1   4.4 |  10.9  51.6  245   8  4   9.0   4.9
  9250  10.6  51.1  225   8  4   6.0   3.3 |  11.4  52.5  240   8  4   7.5   4.1
  9000  11.0  51.8  220   8  4   7.6   4.2 |  12.0  53.6  240   7  4   8.5   4.7
  8750  11.6  52.9  215   8  4   8.0   4.4 |  12.7  54.9  235   7  3   8.9   4.9
  8500  12.2  54.0  210   7  4   8.8   4.8 |  13.3  55.9  235   6  3   8.6   4.7
  8250  12.9  55.2  210   7  4   9.7   5.3 |  13.9  57.0  235   6  3   8.3   4.6
  8000  13.6  56.5  210   7  3   9.9   5.4 |  14.6  58.3  235   6  3   9.1   5.0
  7750  14.3  57.7  210   7  3  10.2   5.6 |  15.2  59.4  235   5  3   9.7   5.3
  7500  15.1  59.2  210   7  3  10.0   5.5 |  16.0  60.8  235   5  3   9.7   5.3
  7250  15.9  60.6  210   7  3  10.0   5.5 |  16.7  62.1  235   5  3  10.0   5.5
  7000  16.6  61.9  210   7  3  10.0   5.5 |  17.4  63.3  235   5  3   9.8   5.4
  6750  17.3  63.1  210   7  3  10.4   5.7 |  18.2  64.8  235   5  3   9.9   5.5
  6500  18.1  64.6  210   6  3  10.9   6.0 |  18.9  66.0  235   5  3  10.5   5.8
  6250  19.0  66.2  210   6  3  11.5   6.3 |  19.7  67.5  235   5  3  11.1   6.1
  6000  19.8  67.6  210   6  3   9.8   5.4 |  20.5  68.9  235   5  3   9.6   5.3
  5750  20.5  68.9  210   6  3  12.5   6.8 |  21.2  70.2  235   5  2   9.5   5.2
  5500  21.7  71.1  210   6  3  16.9   9.2 |  22.0  71.6  240   5  2  11.2   6.1
  5250  22.8  73.0  215   6  3  13.4   7.4 |  22.8  73.0  240   5  2   9.8   5.4
  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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