Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 021251
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0651 MDT Wednesday, September 2, 2015

This forecast is for Wednesday, September 2, 2015:

If the trigger temperature of 79.6 F/26.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1185 ft/min (6.0 m/s)
   Maximum height of thermals.................. 16003 ft MSL (11164 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 C
Time of trigger temperature.................... 1145 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................. 9739 ft MSL (4899 ft AGL)
Thermal soaring outlook for Thursday 09/03..... Good

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

Remarks...

Sunrise/Sunset.................... 06:43:32 / 19:44:50 MDT
Total possible sunshine........... 13 hr 1 min 18 sec (781 min 18 sec)
Altitude of sun at 13:13:44 MDT... 58.70 degrees

Upper air data from rawinsonde observation taken on 09/02/2015 at 0600 MDT

Freezing level.................. 14999 ft MSL (10160 ft AGL)
Convective condensation level... 14007 ft MSL (9168 ft AGL)
Lifted condensation level....... 14675 ft MSL (9835 ft AGL)
Lifted index.................... -1.8
K index......................... +27.3

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  -66.5 -87.7   255   38   20   2.7   1.5   84.7 184.4    30.9      M    M
 45000  -62.3 -80.1   245   55   28   0.3   0.2   66.2 151.1    21.8      M    M
 40000  -55.4 -67.7   240   59   30   8.2   4.5   54.1 129.4    15.3      M    M
 38000  -50.5 -58.9   240   51   26   7.7   4.2   52.7 126.8    14.8      M    M
 36000  -45.4 -49.7   240   43   22   6.5   3.6   51.8 125.2    14.5      M    M
 34000  -40.4 -40.7   245   37   19   9.6   5.3   50.6 123.0    14.0      M    M
 32000  -35.4 -31.7   250   38   20  11.2   6.1   48.4 119.1    12.8      M    M
 30000  -30.4 -22.7   250   40   21   7.3   4.0   47.2 117.0    12.2      M    M
 29000  -28.1 -18.6   255   38   20   8.3   4.6   46.5 115.7    11.8      M    M
 28000  -25.6 -14.1   255   37   19   8.8   4.8   46.0 114.8    11.5      M    M
 27000  -23.7 -10.7   255   33   17   6.6   3.6   44.6 112.3    10.6      M    M
 26000  -21.7  -7.1   255   28   15   6.5   3.6   43.3 110.0     9.7      M    M
 25000  -19.8  -3.6   255   24   12   8.4   4.4   42.2 107.9     8.9      M    M
 24000  -17.3   0.9   250   17    9   7.8   4.3   41.6 106.9     8.5      M    M
 23000  -15.0   5.0   250   20   10   7.9   4.3   40.8 105.5     8.0      M    M
 22000  -12.8   9.0   250   24   12   4.3   2.4   40.0 103.9     7.4      M    M
 21000  -12.1  10.2   250   27   14   3.1   1.7   37.5  99.4     5.2      M    M
 20000  -10.6  12.9   245   24   12   3.3   1.8   35.8  96.5     3.8      M    M
 19500   -9.7  14.5   240   22   11   6.7   3.7   35.2  95.4     3.3      M    M
 19000   -9.1  15.6   235   21   11   2.3   1.3   34.2  93.6     2.4      M    M
 18500   -8.5  16.7   235   20   10   6.1   3.4   33.3  91.9     1.5      M    M
 18000   -7.4  18.7   235   20   10   8.0   4.4   32.9  91.2     1.2      M    M
 17500   -6.2  20.8   235   19   10   8.2   4.5   32.6  90.7     0.9      M    M
 17000   -4.5  23.9   235   19   10   8.3   4.5   32.2  90.0     0.5      M    M
 16500   -3.3  26.1   235   18    9   8.3   4.6   32.0  89.6     0.2      M    M
 16000   -2.1  28.2   235   18    9   8.4   4.6   31.8  89.3    -0.0    974  4.9
 15500   -0.9  30.4   235   16    8   8.5   4.7   31.6  88.8    -0.3    922  4.7
 15000    0.1  32.2   240   15    8   5.8   3.2   31.1  88.0    -0.7    878  4.5
 14500    1.2  34.2   240   14    7   8.5   4.7   30.8  87.4    -1.1    832  4.2
 14000    2.4  36.3   245   13    7   8.4   4.6   30.5  87.0    -1.4    781  4.0
 13500    3.6  38.5   250   13    7   8.4   4.6   30.3  86.5    -1.7    731  3.7
 13000    4.7  40.5   250   13    7   8.4   4.6   30.1  86.1    -2.0    680  3.5
 12500    5.9  42.6   255   13    7   8.4   4.6   29.9  85.7    -2.2    630  3.2
 12000    7.1  44.8   255   13    7   8.4   4.6   29.7  85.4    -2.5    579  2.9
 11500    8.4  47.1   255   14    7   9.2   5.0   29.5  85.1    -2.7    527  2.7
 11000    9.8  49.6   250   14    7   9.3   5.1   29.4  85.0    -2.8    470  2.4
 10500   11.2  52.2   250   15    8   9.3   5.1   29.4  84.9    -2.9    414  2.1
 10250   11.9  53.4   250   14    7   9.2   5.1   29.3  84.8    -2.9    385  2.0
 10000   12.6  54.7   245   13    7   9.6   5.2   29.3  84.7    -2.9    356  1.8
  9750   13.2  55.8   245   13    6   6.3   3.4   29.2  84.6    -3.0    329  1.7
  9500   13.6  56.5   240   12    6   3.5   1.9   28.8  83.8    -3.4    313  1.6
  9250   13.9  57.0   240   11    6   4.2   2.3   28.3  83.0    -3.8    296  1.5
  9000   14.2  57.6   235   10    5   4.2   2.3   27.9  82.2    -4.2    279  1.4
  8750   14.6  58.3   215    9    5   7.0   3.9   27.5  81.6    -4.6    260  1.3
  8500   15.2  59.4   195   10    5   9.2   5.1   27.4  81.4    -4.7    234  1.2
  8250   15.8  60.4   180   11    6   7.6   4.2   27.4  81.2    -4.8    207  1.1
  8000   16.2  61.2   165   14    7   3.2   1.8   27.0  80.7    -5.1    188  1.0
  7750   16.3  61.3   160   15    8   0.9   0.5   26.4  79.5    -5.8    179  0.9
  7500   16.3  61.3   155   16    8   1.6   0.9   25.8  78.4    -6.5    171  0.9
  7250   16.4  61.5   155   17    9   1.4   0.8   25.1  77.2    -7.2    162  0.8
  7000   16.2  61.2   150   19   10  -8.1  -4.4   24.3  75.7    -8.1    159  0.8
  6750   15.5  59.9   145   18    9  -2.8  -1.6   22.8  73.0    -9.6    173  0.9
  6500   16.0  60.8   135   16    8  10.1   5.5   22.5  72.5    -9.9    152  0.8
  6250   16.6  61.9   130   16    8   8.8   4.8   22.5  72.4   -10.0    124  0.6
  6000   17.3  63.1   120   15    8   8.9   4.9   22.4  72.4   -10.1     97  0.5
  5750   17.9  64.2   115   14    7   9.8   5.4   22.4  72.3   -10.2     70  0.4
  5500   18.6  65.5   115   12    6   6.1   3.3   22.3  72.2   -10.2     43  0.2
  5250   18.8  65.8   110   11    6   0.8   0.4   21.8  71.2   -10.8     30  0.2
  5000   18.8  65.8   110   10    5  -1.9  -1.0   21.0  69.9   -11.5     22  0.1

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

           09/02/2015 at 0900 MDT          |       09/02/2015 at 1200 MDT
                                           |
K index... +26.4  LI... +270.7             | K index... +30.9  LI... +269.9
CAPE... +134.0  CIN... -22.3               | CAPE... +537.3  CIN... -17.9
                                           |
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 -64.4 -83.9  250  39 20   0.9   0.5 | -64.3 -83.7  240  36 18  -0.2  -0.1
 45000 -62.0 -79.6  245  55 28   3.7   2.0 | -62.6 -80.7  245  51 26   4.3   2.4
 40000 -55.3 -67.5  240  53 27   8.6   4.7 | -55.3 -67.5  245  46 24   8.8   4.8
 38000 -50.0 -58.0  240  47 24   8.7   4.8 | -50.0 -58.0  240  45 23   8.9   4.9
 36000 -44.8 -48.6  240  42 21   8.8   4.8 | -44.7 -48.5  235  44 23   9.0   4.9
 34000 -39.8 -39.6  245  38 20   8.2   4.5 | -39.8 -39.6  230  40 20   7.9   4.4
 32000 -34.9 -30.8  250  36 19   8.1   4.4 | -35.1 -31.2  230  35 18   7.8   4.3
 30000 -30.2 -22.4  255  35 18   7.7   4.2 | -30.0 -22.0  240  31 16   7.5   4.1
 29000 -27.3 -17.1  260  34 18   7.8   4.3 | -27.7 -17.9  245  30 15   7.5   4.1
 28000 -25.0 -13.0  260  34 17   7.2   4.0 | -25.5 -13.9  245  29 15   7.4   4.1
 27000 -22.9  -9.2  260  32 16   7.2   3.9 | -23.3  -9.9  250  27 14   7.4   4.1
 26000 -20.7  -5.3  260  29 15   7.2   3.9 | -21.0  -5.8  250  25 13   7.4   4.1
 25000 -18.6  -1.5  260  27 14   7.0   3.9 | -18.8  -1.8  255  23 12   7.3   4.0
 24000 -16.6   2.1  260  26 13   6.5   3.6 | -16.7   1.9  255  22 11   6.9   3.8
 23000 -14.6   5.7  260  25 13   6.5   3.6 | -14.6   5.7  255  22 11   6.9   3.8
 22000 -12.6   9.3  260  23 12   5.8   3.2 | -12.5   9.5  255  22 11   6.3   3.4
 21000 -11.3  11.7  260  23 12   4.1   2.3 | -11.0  12.2  255  22 11   5.0   2.7
 20000 -10.1  13.8  255  23 12   4.2   2.3 |  -9.5  14.9  255  22 11   5.0   2.8
 19500  -9.6  14.7  255  23 12   4.1   2.3 |  -8.8  16.2  255  22 12   5.0   2.7
 19000  -8.9  16.0  255  22 11   5.9   3.2 |  -8.0  17.6  250  22 11   5.9   3.2
 18500  -8.0  17.6  255  21 11   5.9   3.2 |  -7.2  19.0  250  21 11   5.9   3.2
 18000  -7.2  19.0  250  19 10   6.7   3.7 |  -6.3  20.7  245  20 10   6.2   3.4
 17500  -6.2  20.8  250  18  9   7.7   4.2 |  -5.4  22.3  245  20 10   6.7   3.7
 17000  -5.1  22.8  245  16  8   7.7   4.2 |  -4.5  23.9  240  19 10   6.8   3.8
 16500  -3.9  25.0  240  15  8   8.0   4.4 |  -3.6  25.5  240  20 10   6.2   3.4
 16000  -2.8  27.0  240  16  8   8.0   4.4 |  -2.7  27.1  245  20 10   6.4   3.5
 15500  -1.6  29.1  240  16  8   7.7   4.2 |  -1.9  28.6  245  21 11   7.2   4.0
 15000  -0.5  31.1  240  17  9   7.6   4.2 |  -0.8  30.6  245  21 11   7.5   4.1
 14500   0.5  32.9  240  17  9   7.7   4.2 |   0.8  33.4  245  21 11   8.5   4.6
 14000   1.6  34.9  240  18  9   8.0   4.4 |   2.0  35.6  245  21 11   8.5   4.6
 13500   3.3  37.9  240  18  9   8.8   4.8 |   3.2  37.8  245  20 10   8.9   4.9
 13000   4.6  40.3  240  17  9   9.0   4.9 |   4.5  40.1  245  19 10   9.0   5.0
 12500   5.9  42.6  240  17  9   9.1   5.0 |   5.8  42.4  240  18  9   9.2   5.0
 12000   7.2  45.0  240  16  8   9.1   5.0 |   7.2  45.0  240  17  9   9.2   5.1
 11500   8.5  47.3  240  15  8   9.0   5.0 |   8.5  47.3  240  15  8   9.1   5.0
 11000   9.8  49.6  240  14  7   8.7   4.8 |   9.9  49.8  235  14  7   8.8   4.8
 10500  11.1  52.0  240  13  7   5.4   3.0 |  11.2  52.2  235  13  6   5.4   3.0
 10250  11.4  52.5  240  13  6   6.4   3.5 |  11.4  52.5  235  12  6   6.6   3.6
 10000  12.1  53.8  240  12  6  11.3   6.2 |  12.2  54.0  230  11  6  11.8   6.5
  9750  12.9  55.2  240  11  6  10.7   5.9 |  13.0  55.4  230  11  5  10.9   6.0
  9500  13.6  56.5  240  10  5   8.1   4.4 |  13.8  56.8  230  10  5   8.7   4.8
  9250  14.1  57.4  235   9  5   6.3   3.5 |  14.3  57.7  230   9  5   7.0   3.8
  9000  14.7  58.5  235   8  4   8.8   4.9 |  14.9  58.8  225   9  4   8.8   4.8
  8750  15.3  59.5  230   7  4   9.0   4.9 |  15.6  60.1  220   8  4   8.7   4.8
  8500  16.0  60.8  220   7  3   8.1   4.5 |  16.2  61.2  220   7  4   8.2   4.5
  8250  16.5  61.7  215   6  3   7.4   4.1 |  16.7  62.1  210   6  3   7.8   4.3
  8000  17.1  62.8  205   6  3   8.0   4.4 |  17.3  63.1  205   6  3   7.6   4.2
  7750  17.7  63.9  195   7  4   7.6   4.1 |  17.8  64.0  195   6  3   8.0   4.4
  7500  18.2  64.8  190   8  4   5.6   3.1 |  18.5  65.3  190   6  3   9.3   5.1
  7250  18.5  65.3  180   9  4   4.8   2.6 |  19.2  66.6  190   6  3  10.0   5.5
  7000  18.9  66.0  175  10  5   5.1   2.8 |  19.9  67.8  190   6  3   9.1   5.0
  6750  19.2  66.6  170  11  6   2.9   1.6 |  20.5  68.9  190   6  3   9.7   5.3
  6500  19.3  66.7  165  11  5   0.6   0.3 |  21.3  70.3  190   6  3  11.0   6.1
  6250  19.3  66.7  160  10  5   1.0   0.6 |  22.2  72.0  190   6  3  11.4   6.3
  6000  19.3  66.7  155   9  5  -0.2  -0.1 |  23.0  73.4  190   6  3   9.6   5.3
  5750  19.3  66.7  145   7  4   3.0   1.6 |  23.6  74.5  190   6  3  10.6   5.8
  5500  19.7  67.5  140   7  3   7.5   4.1 |  24.6  76.3  190   6  3  13.7   7.5
  5250  20.1  68.2  140   6  3   4.0   2.2 |  25.5  77.9  190   6  3  11.2   6.1
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/02/2015 at 1500 MDT          |       09/02/2015 at 1800 MDT
                                           |
K index... +30.1  LI... +271.4             | K index... +31.1  LI... +271.2
CAPE... +291.4  CIN... -4.5                | CAPE... +345.6  CIN... -12.4
                                           |
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 -64.8 -84.6  240  35 18   0.4   0.2 | -64.8 -84.6  235  38 19   0.3   0.2
 45000 -62.4 -80.3  240  47 24   4.3   2.3 | -62.5 -80.5  235  45 23   4.1   2.2
 40000 -55.2 -67.4  240  43 22   8.5   4.6 | -55.5 -67.9  240  39 20   8.9   4.9
 38000 -50.1 -58.2  235  44 23   8.5   4.7 | -50.2 -58.4  235  41 21   9.0   4.9
 36000 -45.0 -49.0  235  45 23   8.5   4.7 | -44.8 -48.6  230  43 22   9.0   4.9
 34000 -39.8 -39.6  230  42 22   8.7   4.8 | -39.5 -39.1  230  44 22   8.7   4.8
 32000 -34.5 -30.1  230  40 21   8.6   4.7 | -34.3 -29.7  230  44 23   8.6   4.7
 30000 -29.6 -21.3  235  35 18   7.1   3.9 | -29.8 -21.6  235  38 19   7.5   4.1
 29000 -27.4 -17.3  240  33 17   7.1   3.9 | -27.0 -16.6  240  33 17   7.5   4.1
 28000 -25.2 -13.4  245  31 16   7.9   4.4 | -24.8 -12.6  245  30 15   7.3   4.0
 27000 -22.9  -9.2  245  29 15   8.0   4.4 | -22.5  -8.5  245  28 14   7.3   4.0
 26000 -20.5  -4.9  245  27 14   8.0   4.4 | -20.3  -4.5  245  26 13   7.4   4.0
 25000 -18.2  -0.8  245  25 13   7.7   4.2 | -18.1  -0.6  250  23 12   7.2   4.0
 24000 -16.1   3.0  245  23 12   6.9   3.8 | -16.1   3.0  250  22 12   7.0   3.8
 23000 -14.0   6.8  245  22 11   6.9   3.8 | -14.0   6.8  250  22 11   7.0   3.8
 22000 -12.0  10.4  245  20 10   6.5   3.6 | -11.9  10.6  255  21 11   6.6   3.6
 21000 -10.2  13.6  245  21 11   5.9   3.3 | -10.2  13.6  250  20 10   5.8   3.2
 20000  -8.5  16.7  245  21 11   5.9   3.3 |  -8.4  16.9  250  20 10   5.8   3.2
 19500  -7.6  18.3  245  22 11   6.0   3.3 |  -7.5  18.5  250  20 10   5.8   3.2
 19000  -6.7  19.9  245  22 11   6.0   3.3 |  -6.6  20.1  250  20 10   6.4   3.5
 18500  -5.9  21.4  245  22 11   6.0   3.3 |  -5.7  21.7  250  20 10   6.4   3.5
 18000  -5.0  23.0  245  22 11   6.0   3.3 |  -4.8  23.4  250  20 11   6.4   3.5
 17500  -4.2  24.4  240  22 11   6.0   3.3 |  -4.0  24.8  250  21 11   6.3   3.4
 17000  -3.3  26.1  240  21 11   6.0   3.3 |  -3.1  26.4  245  21 11   6.3   3.4
 16500  -2.5  27.5  240  21 11   5.6   3.1 |  -2.2  28.0  245  21 11   6.6   3.6
 16000  -1.7  28.9  235  20 10   5.7   3.1 |  -1.3  29.7  245  20 10   6.7   3.7
 15500  -0.9  30.4  235  19 10   7.0   3.8 |  -0.4  31.3  245  19 10   6.9   3.8
 15000   0.1  32.2  235  18  9   7.5   4.1 |   0.6  33.1  245  18  9   7.1   3.9
 14500   1.7  35.1  235  17  9   7.5   4.1 |   1.6  34.9  245  17  9   7.4   4.1
 14000   2.8  37.0  235  16  8   7.5   4.1 |   3.3  37.9  240  16  8   8.2   4.5
 13500   3.9  39.0  235  15  8   7.1   3.9 |   4.5  40.1  240  15  8   8.0   4.4
 13000   4.9  40.8  235  13  7   7.0   3.8 |   5.6  42.1  240  14  7   7.9   4.3
 12500   5.8  42.4  235  12  6   7.9   4.3 |   6.7  44.1  235  12  6   8.7   4.8
 12000   7.1  44.8  235  11  6   8.8   4.8 |   8.1  46.6  235  11  6   9.7   5.3
 11500   8.4  47.1  235  10  5   9.1   5.0 |   9.5  49.1  230  10  5   9.5   5.2
 11000   9.8  49.6  235  10  5   9.1   5.0 |  10.8  51.4  225   9  5   8.7   4.8
 10500  11.1  52.0  235   9  5   5.0   2.7 |  12.1  53.8  225   8  4   5.6   3.1
 10250  11.4  52.5  235   8  4   6.0   3.3 |  12.4  54.3  220   8  4   6.1   3.4
 10000  12.2  54.0  235   8  4  12.1   6.6 |  13.2  55.8  220   7  4  10.7   5.9
  9750  12.9  55.2  235   7  4  11.1   6.1 |  13.9  57.0  220   6  3   9.9   5.4
  9500  13.7  56.7  235   7  3   8.9   4.9 |  14.6  58.3  220   6  3   8.6   4.7
  9250  14.3  57.7  235   6  3   7.8   4.3 |  15.2  59.4  215   5  3   6.9   3.8
  9000  15.0  59.0  240   6  3  10.3   5.6 |  15.7  60.3  215   4  2   7.8   4.3
  8750  15.7  60.3  240   6  3  10.2   5.6 |  16.3  61.3  210   4  2   7.6   4.2
  8500  16.5  61.7  240   6  3  10.2   5.6 |  16.9  62.4  205   3  1   8.0   4.4
  8250  17.2  63.0  240   6  3  10.2   5.6 |  17.5  63.5  205   2  1   8.5   4.7
  8000  18.0  64.4  240   6  3   9.8   5.4 |  18.1  64.6  205   2  1   8.7   4.8
  7750  18.7  65.7  240   6  3   9.7   5.3 |  18.8  65.8  210   2  1   8.9   4.9
  7500  19.4  66.9  240   6  3  10.0   5.5 |  19.4  66.9  210   2  1   9.5   5.2
  7250  20.2  68.4  240   5  3  10.3   5.7 |  20.2  68.4  210   2  1  10.0   5.5
  7000  20.9  69.6  240   5  3   9.8   5.4 |  20.9  69.6  210   2  1   9.8   5.4
  6750  21.7  71.1  240   5  3  10.0   5.5 |  21.6  70.9  210   2  1   9.8   5.4
  6500  22.5  72.5  240   5  3  10.7   5.9 |  22.4  72.3  215   2  1  10.0   5.5
  6250  23.3  73.9  240   5  3  11.1   6.1 |  23.1  73.6  215   2  1  10.3   5.7
  6000  24.1  75.4  240   5  3   9.9   5.4 |  23.9  75.0  220   2  1   9.6   5.3
  5750  24.8  76.6  245   5  3  11.5   6.3 |  24.6  76.3  220   2  1   9.0   4.9
  5500  25.8  78.4  245   5  3  14.3   7.9 |  25.2  77.4  225   2  1   9.3   5.1
  5250  26.8  80.2  245   5  3  12.1   6.6 |  25.9  78.6  230   2  1   9.1   5.0
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken at Walker Field in Grand
Junction, Colorado at

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

and may not be representative of other areas along the Western Slope of
Colorado.  Note that some elevations in numerical weather prediction models
differ from actual station elevations, which can lead to data which appear
to be below ground.  Erroneous data such as these should not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613


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