Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 231239
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0639 MDT Sunday, August 23, 2015

This forecast is for Sunday, August 23, 2015:

If the trigger temperature of 83.7 F/28.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 718 ft/min (3.6 m/s)
   Maximum height of thermals.................. 13742 ft MSL (8903 ft AGL)

Forecast maximum temperature................... 92.0 F/33.8 C
Time of trigger temperature.................... 1200 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10525 ft MSL (5686 ft AGL)
Thermal soaring outlook for Monday 08/24....... Good

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

Remarks...

Sunrise/Sunset.................... 06:34:28 / 19:59:40 MDT
Total possible sunshine........... 13 hr 25 min 13 sec (805 min 13 sec)
Altitude of sun at 13:16:41 MDT... 62.22 degrees

Upper air data from rawinsonde observation taken on 08/23/2015 at 0600 MDT

Freezing level.................. 16201 ft MSL (11362 ft AGL)
Convective condensation level... 19787 ft MSL (14948 ft AGL)
Lifted condensation level....... 18881 ft MSL (14042 ft AGL)
Lifted index.................... +2.0
K index......................... +3.2

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  -65.2 -85.4   285   34   18   5.4   2.9   85.3 185.6    30.2      M    M
 45000  -59.5 -75.1   275   37   19   6.0   3.3   70.0 157.9    22.8      M    M
 40000  -53.4 -64.1   265   38   20   1.0   0.5   57.3 135.1    15.9      M    M
 38000  -49.9 -57.8   255   36   18   7.4   4.1   52.7 126.8    13.2      M    M
 36000  -45.4 -49.7   255   27   14   9.3   5.1   50.7 123.2    12.2      M    M
 34000  -40.5 -40.9   270   24   12   7.9   4.3   49.4 120.8    11.5      M    M
 32000  -35.7 -32.3   260   23   12   7.7   4.2   48.0 118.3    10.8      M    M
 30000  -30.6 -23.1   240   17    9   9.3   5.1   47.0 116.6    10.3      M    M
 29000  -28.8 -19.8   235   12    6   7.1   3.9   45.4 113.8     9.3      M    M
 28000  -26.8 -16.2   215   14    7   6.5   3.5   44.2 111.6     8.4      M    M
 27000  -24.8 -12.6   220   13    7   8.1   4.4   43.0 109.4     7.6      M    M
 26000  -22.4  -8.3   220   13    7   8.0   4.4   42.3 108.1     7.1      M    M
 25000  -20.0  -4.0   225   12    6   8.1   4.4   41.7 107.0     6.7      M    M
 24000  -17.5   0.5   220   12    6   8.3   4.5   41.1 106.0     6.3      M    M
 23000  -15.0   5.0   210   12    6   8.3   4.6   40.6 105.1     6.0      M    M
 22000  -12.5   9.5   230   12    6   8.1   4.5   40.1 104.1     5.5      M    M
 21000  -11.3  11.7   245   11    5   3.4   1.9   38.1 100.6     3.8      M    M
 20000   -9.1  15.6   265   11    5   8.3   4.6   36.6  97.9     2.4      M    M
 19500   -7.9  17.8   275   13    7   6.3   3.4   36.3  97.4     2.2      M    M
 19000   -7.3  18.9   270   13    7   4.6   2.5   35.4  95.7     1.3      M    M
 18500   -6.3  20.7   255   13    6   8.7   4.8   34.8  94.7     0.8      M    M
 18000   -4.9  23.2   245   13    7   9.0   5.0   34.7  94.5     0.8      M    M
 17500   -3.5  25.7   255   15    8   9.1   5.0   34.6  94.4     0.8      M    M
 17000   -2.1  28.2   260   16    8   9.1   5.0   34.6  94.2     0.8      M    M
 16500   -0.7  30.7   275   16    8   9.2   5.0   34.4  94.0     0.7      M    M
 16000    0.8  33.4   285   17    9   9.1   5.0   34.4  93.8     0.7      M    M
 15500    2.1  35.8   285   18    9   8.7   4.8   34.2  93.5     0.5      M    M
 15000    3.4  38.1   290   18    9   8.7   4.8   34.0  93.2     0.3      M    M
 14500    4.7  40.5   290   19   10   8.7   4.8   33.8  92.9     0.2      M    M
 14000    6.0  42.8   290   19   10   8.9   4.9   33.7  92.7     0.1      M    M
 13500    7.2  45.0   295   19   10   7.3   4.0   33.4  92.2    -0.2    691  3.5
 13000    8.3  46.9   295   20   10   7.3   4.0   33.0  91.4    -0.6    644  3.3
 12500    9.4  48.9   300   20   11   7.3   4.0   32.6  90.7    -1.0    597  3.0
 12000   10.5  50.9   300   21   11   7.7   4.2   32.3  90.1    -1.3    549  2.8
 11500   11.7  53.1   290   18    9   7.7   4.2   32.0  89.6    -1.5    497  2.5
 11000   13.0  55.4   280   15    8   5.4   3.0   31.7  89.1    -1.8    445  2.3
 10500   13.2  55.8   270   13    7   4.1   2.3   30.6  87.1    -3.0    424  2.2
 10250   13.4  56.1   265   12    6   6.3   3.5   30.3  86.5    -3.5    408  2.1
 10000   13.9  57.0   270   11    6   7.8   4.3   30.0  86.1    -3.8    386  2.0
  9750   14.5  58.1   275   10    5   8.0   4.4   29.9  85.8    -3.9    361  1.8
  9500   15.1  59.2   280   10    5   8.0   4.4   29.8  85.6    -4.0    335  1.7
  9250   15.7  60.3   285    9    5   8.0   4.4   29.6  85.4    -4.2    310  1.6
  9000   16.3  61.3   290    8    4   8.0   4.4   29.5  85.1    -4.3    285  1.4
  8750   16.9  62.4   290    8    4   8.0   4.4   29.4  84.9    -4.5    260  1.3
  8500   17.5  63.5   295    8    4   8.0   4.4   29.2  84.6    -4.6    234  1.2
  8250   18.1  64.6   295    8    4   7.9   4.3   29.1  84.4    -4.8    209  1.1
  8000   18.7  65.7   300    8    4   8.2   4.5   29.0  84.1    -4.9    184  0.9
  7750   19.3  66.7   295    8    4   7.0   3.8   28.8  83.9    -5.1    159  0.8
  7500   19.7  67.5   290    8    4   3.5   1.9   28.5  83.2    -5.4    140  0.7
  7250   19.9  67.8   285    8    4   1.8   1.0   27.9  82.2    -6.0    127  0.6
  7000   20.1  68.2   275    8    4   4.8   2.6   27.4  81.3    -6.5    113  0.6
  6750   20.5  68.9   275    7    4   6.8   3.7   27.1  80.8    -6.8     93  0.5
  6500   21.0  69.8   275    6    3   6.2   3.4   26.8  80.3    -7.1     72  0.4
  6250   21.4  70.5   275    5    3   6.6   3.6   26.6  79.8    -7.4     51  0.3
  6000   21.9  71.4   275    4    2   5.8   3.2   26.3  79.4    -7.7     30  0.2
  5750   22.3  72.1   275    3    2   8.7   4.7   26.1  78.9    -8.0      9  0.0
  5500   22.8  73.0   275    2    1  -2.1  -1.1   25.8  78.5    -8.3      M    M
  5250   21.9  71.4   275    1    1 -15.0  -8.2   24.2  75.6   -10.0      7  0.0
  5000   20.8  69.4   000    0    0 -11.5  -6.3   22.5  72.5   -11.8     31  0.2

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

           08/23/2015 at 0900 MDT          |       08/23/2015 at 1200 MDT
                                           |
K index... +11.1  LI... +275.3             | K index... +19.7  LI... +273.6
CAPE... 0.0  CIN... -0.4                   | CAPE... 0.0  CIN... -0.1
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -64.6 -84.3  280  21 11   2.4   1.3 | -65.1 -85.2  270  23 12   2.7   1.5
 45000 -59.1 -74.4  280  33 17   6.4   3.5 | -59.1 -74.4  275  32 17   6.8   3.7
 40000 -49.9 -57.8  285  36 18   3.8   2.1 | -49.0 -56.2  285  37 19   3.8   2.1
 38000 -47.4 -53.3  275  28 14   3.7   2.0 | -46.7 -52.1  280  31 16   3.8   2.1
 36000 -45.2 -49.4  260  22 11   4.5   2.4 | -44.4 -47.9  270  26 13   4.5   2.5
 34000 -40.4 -40.7  260  19 10   8.2   4.5 | -40.1 -40.2  265  23 12   7.4   4.0
 32000 -35.5 -31.9  255  17  9   8.2   4.5 | -35.7 -32.3  255  20 10   7.2   4.0
 30000 -30.9 -23.6  255  17  9   7.6   4.2 | -31.2 -24.2  255  18  9   7.6   4.2
 29000 -28.6 -19.5  255  18  9   7.6   4.2 | -28.9 -20.0  260  18  9   7.7   4.2
 28000 -26.4 -15.5  255  19 10   7.1   3.9 | -26.7 -16.1  260  17  9   6.8   3.7
 27000 -24.3 -11.7  255  18  9   7.0   3.8 | -24.7 -12.5  265  16  8   6.5   3.6
 26000 -22.2  -8.0  255  18  9   7.0   3.8 | -22.8  -9.0  270  15  7   6.5   3.6
 25000 -20.1  -4.2  255  17  9   6.9   3.8 | -20.8  -5.4  275  13  7   6.5   3.6
 24000 -18.2  -0.8  260  16  8   6.1   3.4 | -18.9  -2.0  275  14  7   6.4   3.5
 23000 -16.4   2.5  270  15  8   6.1   3.4 | -17.0   1.4  280  14  7   6.4   3.5
 22000 -14.0   6.8  280  14  7   6.9   3.8 | -14.6   5.7  285  14  7   7.3   4.0
 21000 -11.9  10.6  280  15  8   7.0   3.8 | -12.4   9.7  285  15  8   7.4   4.0
 20000  -9.9  14.2  280  16  8   7.0   3.8 | -10.1  13.8  285  15  8   7.4   4.1
 19500  -8.8  16.2  280  16  8   7.4   4.0 |  -9.0  15.8  285  16  8   7.6   4.1
 19000  -7.7  18.1  280  16  8   7.9   4.3 |  -7.9  17.8  290  16  8   7.7   4.2
 18500  -6.5  20.3  280  17  9   7.9   4.3 |  -6.7  19.9  290  16  8   7.8   4.3
 18000  -5.3  22.5  285  17  9   8.6   4.7 |  -5.6  21.9  295  17  9   7.3   4.0
 17500  -4.0  24.8  290  18  9   8.6   4.7 |  -4.6  23.7  305  18  9   7.4   4.1
 17000  -2.7  27.1  295  18  9   8.0   4.4 |  -3.5  25.7  310  19 10   8.2   4.5
 16500  -1.6  29.1  300  20 10   7.4   4.0 |  -2.3  27.9  310  19 10   8.9   4.9
 16000  -0.6  30.9  305  22 11   7.4   4.1 |  -1.0  30.2  305  19 10   9.1   5.0
 15500   0.6  33.1  310  23 12   8.8   4.8 |   0.4  32.7  305  19 10   9.8   5.4
 15000   1.9  35.4  310  25 13   8.7   4.8 |   1.8  35.2  305  18  9   9.9   5.4
 14500   3.2  37.8  310  26 14   9.4   5.1 |   3.2  37.8  300  18  9   9.2   5.0
 14000   4.6  40.3  310  26 13   9.4   5.2 |   4.6  40.3  300  18  9   9.2   5.0
 13500   5.9  42.6  310  26 13   9.1   5.0 |   6.0  42.8  300  18  9   9.2   5.0
 13000   7.3  45.1  305  25 13   8.9   4.9 |   7.4  45.3  305  17  9   9.2   5.0
 12500   8.6  47.5  305  24 12   8.9   4.9 |   8.7  47.7  305  17  9   9.0   4.9
 12000   9.9  49.8  305  22 12   8.9   4.9 |  10.1  50.2  300  17  9   8.8   4.8
 11500  11.2  52.2  305  21 11   8.6   4.7 |  11.4  52.5  300  16  8   8.7   4.8
 11000  12.4  54.3  300  19 10   7.7   4.2 |  12.7  54.9  300  15  8   8.3   4.6
 10500  13.6  56.5  295  16  8   4.3   2.3 |  14.0  57.2  300  14  7   3.8   2.1
 10250  13.8  56.8  295  15  8   3.7   2.0 |  14.1  57.4  300  14  7   4.5   2.5
 10000  14.3  57.7  295  14  7   8.4   4.6 |  14.9  58.8  295  13  7  11.1   6.1
  9750  14.9  58.8  290  12  6   8.1   4.4 |  15.6  60.1  295  12  6   9.9   5.4
  9500  15.4  59.7  285  11  6   7.2   4.0 |  16.4  61.5  295  12  6   8.1   4.5
  9250  15.9  60.6  280  10  5   5.8   3.2 |  16.8  62.2  295  11  5   5.8   3.2
  9000  16.4  61.5  280   9  5   7.1   3.9 |  17.3  63.1  295  10  5   7.2   3.9
  8750  16.9  62.4  275   8  4   8.8   4.8 |  17.9  64.2  290   8  4   7.7   4.2
  8500  17.5  63.5  270   7  3   6.2   3.4 |  18.4  65.1  290   7  4   6.7   3.7
  8250  17.8  64.0  260   6  3   3.9   2.2 |  18.9  66.0  285   6  3   5.8   3.2
  8000  18.2  64.8  250   5  3   4.3   2.4 |  19.3  66.7  285   5  3   6.5   3.6
  7750  18.4  65.1  235   4  2   3.9   2.2 |  19.8  67.6  280   4  2   7.2   3.9
  7500  18.7  65.7  215   4  2   3.2   1.8 |  20.3  68.5  275   3  2   7.5   4.1
  7250  18.9  66.0  200   5  3   2.7   1.5 |  20.8  69.4  270   3  1   7.5   4.1
  7000  19.0  66.2  185   6  3   2.9   1.6 |  21.3  70.3  260   2  1   8.1   4.5
  6750  19.2  66.6  175   7  4   1.4   0.8 |  21.9  71.4  255   2  1  10.1   5.5
  6500  19.2  66.6  170   7  4  -0.2  -0.1 |  22.7  72.9  250   2  1  10.8   5.9
  6250  19.1  66.4  165   6  3  -0.7  -0.4 |  23.5  74.3  250   2  1  10.5   5.7
  6000  19.0  66.2  160   6  3   0.9   0.5 |  24.3  75.7  250   2  1  10.5   5.7
  5750  19.3  66.7  155   6  3   8.8   4.8 |  25.2  77.4  250   2  1  17.1   9.4
  5500  20.3  68.5  150   5  3  16.8   9.2 |  26.9  80.4  255   2  1  28.4  15.6
  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

           08/23/2015 at 1500 MDT          |       08/23/2015 at 1800 MDT
                                           |
K index... +22.5  LI... +273.0             | K index... +20.4  LI... +273.8
CAPE... +26.8  CIN... -29.3                | CAPE... 0.0  CIN... -0.6
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.2 -85.4  265  24 13   2.4   1.3 | -65.7 -86.3  265  25 13   2.0   1.1
 45000 -58.9 -74.0  275  34 17   7.0   3.8 | -60.3 -76.5  270  33 17   7.0   3.9
 40000 -49.0 -56.2  290  39 20   4.2   2.3 | -49.7 -57.5  275  37 19   4.8   2.7
 38000 -46.5 -51.7  285  35 18   4.3   2.3 | -46.8 -52.2  275  36 19   4.9   2.7
 36000 -43.9 -47.0  280  31 16   4.5   2.5 | -43.9 -47.0  275  36 18   5.3   2.9
 34000 -39.7 -39.5  275  28 15   7.3   4.0 | -39.5 -39.1  280  32 16   7.6   4.2
 32000 -35.3 -31.5  265  27 14   7.3   4.0 | -34.9 -30.8  280  28 14   7.6   4.2
 30000 -31.1 -24.0  260  23 12   7.1   3.9 | -30.6 -23.1  280  25 13   7.1   3.9
 29000 -28.5 -19.3  260  20 11   7.2   3.9 | -27.9 -18.2  280  23 12   7.2   3.9
 28000 -26.4 -15.5  260  19 10   6.7   3.7 | -25.8 -14.4  275  21 11   7.0   3.9
 27000 -24.4 -11.9  265  17  9   6.8   3.7 | -23.7 -10.7  275  20 10   7.1   3.9
 26000 -22.4  -8.3  265  16  8   6.8   3.7 | -21.6  -6.9  280  18  9   7.1   3.9
 25000 -20.3  -4.5  265  15  8   6.7   3.7 | -19.6  -3.3  280  17  9   6.7   3.7
 24000 -18.4  -1.1  270  14  7   6.7   3.7 | -17.7   0.1  280  15  8   6.4   3.5
 23000 -16.4   2.5  275  13  7   6.7   3.7 | -15.8   3.6  280  12  6   6.4   3.5
 22000 -14.4   6.1  285  13  7   7.3   4.0 | -13.9   7.0  280  10  5   7.0   3.9
 21000 -12.1  10.2  280  13  7   7.5   4.1 | -11.8  10.8  285  10  5   7.3   4.0
 20000  -9.9  14.2  280  13  7   7.6   4.2 |  -9.6  14.7  285  10  5   7.3   4.0
 19500  -8.8  16.2  280  13  7   7.6   4.2 |  -8.6  16.5  285  10  5   7.4   4.1
 19000  -7.6  18.3  285  13  6   7.9   4.3 |  -7.4  18.7  290   9  5   7.7   4.2
 18500  -6.4  20.5  290  12  6   7.9   4.4 |  -6.3  20.7  300   8  4   7.7   4.2
 18000  -5.2  22.6  300  12  6   7.5   4.1 |  -5.1  22.8  305   8  4   8.1   4.5
 17500  -4.2  24.4  305  12  6   7.4   4.1 |  -3.9  25.0  305   8  4   8.2   4.5
 17000  -3.1  26.4  305  13  6   7.7   4.2 |  -2.7  27.1  310   8  4   8.4   4.6
 16500  -1.9  28.6  310  12  6   8.7   4.8 |  -1.4  29.5  310   7  4   8.9   4.9
 16000  -0.7  30.7  305  12  6   8.7   4.8 |  -0.1  31.8  310   7  4   8.9   4.9
 15500   0.6  33.1  305  12  6   8.8   4.8 |   1.2  34.2  305   7  4   8.8   4.8
 15000   1.9  35.4  305  12  6   8.8   4.9 |   2.5  36.5  305   7  3   8.8   4.8
 14500   3.2  37.8  300  12  6   9.3   5.1 |   3.8  38.8  305   7  3   9.1   5.0
 14000   5.2  41.4  300  12  6   9.5   5.2 |   5.1  41.2  305   7  3   9.2   5.0
 13500   6.6  43.9  300  12  6   9.7   5.3 |   7.2  45.0  300   7  3   9.1   5.0
 13000   8.1  46.6  300  12  6   9.7   5.3 |   8.5  47.3  300   7  3   9.1   5.0
 12500   9.5  49.1  300  12  6   9.2   5.1 |   9.9  49.8  295   7  4   9.0   4.9
 12000  10.8  51.4  300  12  6   9.2   5.0 |  11.2  52.2  295   7  4   9.0   4.9
 11500  12.2  54.0  300  12  6   9.0   5.0 |  12.5  54.5  290   8  4   9.0   4.9
 11000  13.5  56.3  300  11  6   9.3   5.1 |  13.8  56.8  290   8  4   9.3   5.1
 10500  14.7  58.5  300  11  6   5.4   3.0 |  15.0  59.0  285   9  5   5.0   2.7
 10250  15.2  59.4  300  10  5   8.7   4.8 |  15.4  59.7  285   9  5   8.3   4.5
 10000  16.0  60.8  300  10  5  11.2   6.2 |  16.2  61.2  285  10  5  11.2   6.1
  9750  16.8  62.2  300  10  5  10.3   5.6 |  17.0  62.6  285  10  5  10.3   5.7
  9500  17.5  63.5  305   9  5   7.0   3.8 |  17.7  63.9  285  10  5   7.7   4.2
  9250  17.9  64.2  305   9  4   7.1   3.9 |  18.2  64.8  285  10  5   7.3   4.0
  9000  18.6  65.5  305   8  4   9.7   5.3 |  18.8  65.8  280  10  5   9.2   5.0
  8750  19.3  66.7  305   7  4   9.1   5.0 |  19.5  67.1  280  10  5   8.7   4.8
  8500  20.0  68.0  305   7  4   8.5   4.7 |  20.1  68.2  280  10  5   8.2   4.5
  8250  20.6  69.1  305   7  3   8.4   4.6 |  20.7  69.3  280  10  5   8.0   4.4
  8000  21.3  70.3  305   6  3   9.1   5.0 |  21.3  70.3  280  10  5   8.9   4.9
  7750  22.0  71.6  305   6  3   9.9   5.5 |  22.0  71.6  275   9  5   9.6   5.3
  7500  22.7  72.9  305   6  3  10.4   5.7 |  22.7  72.9  275   9  5   9.8   5.4
  7250  23.5  74.3  305   6  3  10.7   5.8 |  23.5  74.3  275   9  5  10.1   5.5
  7000  24.3  75.7  300   6  3  10.1   5.6 |  24.2  75.6  275   9  5   9.6   5.3
  6750  25.0  77.0  300   6  3  10.4   5.7 |  24.9  76.8  275   9  5  10.0   5.5
  6500  25.9  78.6  300   6  3  11.0   6.0 |  25.7  78.3  275   9  5  10.6   5.8
  6250  26.7  80.1  295   6  3  10.9   6.0 |  26.5  79.7  275   9  5  10.8   5.9
  6000  27.5  81.5  295   5  3  10.7   5.9 |  27.3  81.1  270   9  5   9.7   5.3
  5750  28.3  82.9  295   5  3  12.9   7.1 |  28.0  82.4  270   8  4   9.6   5.3
  5500  29.4  84.9  295   5  3  15.2   8.3 |  28.7  83.7  270   8  4  11.0   6.0
  5250  30.5  86.9  300   5  3  13.5   7.4 |  29.5  85.1  275   8  4   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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