Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 221258
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0657 MDT Wednesday, March 22, 2017

This forecast is for Wednesday, March 22, 2017:

If the trigger temperature of 71.2 F/21.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 547 ft/min (2.8 m/s)
   Maximum height of thermals.................. 14939 ft MSL (10100 ft AGL)

Forecast maximum temperature................... 74.0 F/23.8 C
Time of trigger temperature.................... 1315 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7203 ft MSL (2364 ft AGL)
Thermal soaring outlook for Thursday 03/23..... Good

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

Remarks...

Sunrise/Sunset.................... 07:13:52 / 19:27:25 MDT
Total possible sunshine........... 12 hr 13 min 34 sec (733 min 34 sec)
Altitude of sun at 13:20:49 MDT... 51.83 degrees

Upper air data from rawinsonde observation taken on 03/22/2017 at 0600 MDT

Freezing level.................. 12341 ft MSL (7502 ft AGL)
Convective condensation level... 17723 ft MSL (12884 ft AGL)
Lifted condensation level....... 17561 ft MSL (12722 ft AGL)
Lifted index.................... +2.7
K index......................... +9.6

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  -63.7 -82.7   245   34   18   5.6   3.1   92.6 198.7    39.7      M    M
 45000  -57.4 -71.3   245   44   23   5.5   3.0   78.7 173.6    33.9      M    M
 40000  -48.9 -56.0   235   71   36   6.2   3.4   67.9 154.2    29.3      M    M
 38000  -48.7 -55.7   245   63   32  -3.8  -2.1   59.3 138.8    24.3      M    M
 36000  -54.3 -65.7   250   77   40   3.9   2.1   42.7 108.9    13.4      M    M
 34000  -52.0 -61.6   250   80   41   8.8   4.8   37.5  99.6    10.1      M    M
 32000  -46.7 -52.1   245   70   36   8.8   4.9   36.8  98.2     9.8      M    M
 30000  -40.9 -41.6   245   65   33   8.3   4.6   36.0  96.8     9.5      M    M
 29000  -38.4 -37.1   245   64   33   8.3   4.6   35.2  95.4     9.0      M    M
 28000  -35.9 -32.6   245   62   32   8.3   4.6   34.6  94.3     8.7      M    M
 27000  -33.4 -28.1   245   61   31   8.3   4.6   34.2  93.5     8.4      M    M
 26000  -31.0 -23.8   245   60   31   8.3   4.6   33.8  92.8     8.2      M    M
 25000  -28.6 -19.5   240   60   31   7.0   3.8   33.1  91.6     7.7      M    M
 24000  -26.5 -15.7   230   58   30   6.9   3.8   32.0  89.6     6.9      M    M
 23000  -24.5 -12.1   225   60   31   6.9   3.8   30.9  87.7     6.1      M    M
 22000  -22.4  -8.3   225   62   32   6.9   3.8   30.0  86.0     5.3      M    M
 21000  -20.4  -4.7   230   55   28   6.9   3.8   28.9  84.0     4.4      M    M
 20000  -18.4  -1.1   235   48   25   7.0   3.8   27.9  82.2     3.6      M    M
 19500  -17.4   0.7   230   48   25   4.7   2.6   27.3  81.1     3.1      M    M
 19000  -16.8   1.8   225   48   25   0.2   0.1   26.3  79.3     2.3      M    M
 18500  -16.9   1.6   220   47   24   5.1   2.8   24.4  75.9     0.7      M    M
 18000  -15.6   3.9   215   46   24   9.3   5.1   24.2  75.6     0.6      M    M
 17500  -14.3   6.3   215   45   23   8.7   4.8   24.1  75.4     0.5      M    M
 17000  -13.0   8.6   215   44   23   8.8   4.8   23.9  75.1     0.3      M    M
 16500  -10.9  12.4   220   42   22   9.4   5.1   23.8  74.9     0.2      M    M
 16000   -9.5  14.9   220   41   21   9.4   5.2   23.8  74.8     0.1      M    M
 15500   -8.1  17.4   225   39   20   9.4   5.2   23.7  74.6     0.0      M    M
 15000   -6.7  19.9   225   36   19   9.6   5.2   23.6  74.6    -0.0    943  4.8
 14500   -5.5  22.1   220   32   17   6.6   3.6   23.4  74.2    -0.2    890  4.5
 14000   -4.5  23.9   220   29   15   8.6   4.7   22.9  73.3    -0.8    848  4.3
 13500   -3.1  26.4   220   27   14   9.6   5.3   22.9  73.3    -0.8    791  4.0
 13000   -1.7  28.9   215   25   13   9.3   5.1   22.9  73.2    -0.9    734  3.7
 12500   -0.3  31.5   215   23   12   9.3   5.1   22.8  73.0    -0.9    677  3.4
 12000    1.1  34.0   210   21   11   9.3   5.1   22.8  73.0    -0.9    620  3.2
 11500    2.5  36.5   215   20   10   9.3   5.1   22.7  72.8    -1.0    563  2.9
 11000    3.9  39.0   220   20   10   9.3   5.1   22.6  72.7    -1.1    506  2.6
 10500    5.3  41.5   220   19   10  10.0   5.5   22.5  72.6    -1.1    449  2.3
 10250    6.1  43.0   225   19   10   9.9   5.4   22.6  72.6    -1.1    419  2.1
 10000    6.8  44.2   225   19   10   8.8   4.8   22.5  72.6    -1.1    391  2.0
  9750    7.4  45.3   225   18    9   8.6   4.7   22.4  72.4    -1.2    364  1.8
  9500    8.1  46.6   225   17    9   8.6   4.7   22.4  72.2    -1.3    337  1.7
  9250    8.7  47.7   225   17    9   8.6   4.7   22.3  72.1    -1.4    311  1.6
  9000    9.3  48.7   225   16    8   8.6   4.7   22.2  72.0    -1.4    284  1.4
  8750   10.0  50.0   225   16    8   8.6   4.7   22.1  71.8    -1.5    257  1.3
  8500   10.6  51.1   225   15    8   8.6   4.7   22.0  71.6    -1.6    231  1.2
  8250   11.3  52.3   225   15    7   8.6   4.7   21.9  71.5    -1.7    204  1.0
  8000   11.9  53.4   225   14    7   8.7   4.8   21.8  71.3    -1.8    178  0.9
  7750   12.6  54.7   220   14    7   8.2   4.5   21.8  71.2    -1.9    151  0.8
  7500   13.0  55.4   210   13    7   3.7   2.0   21.5  70.7    -2.2    129  0.7
  7250   13.1  55.6   200   13    7   1.5   0.8   20.9  69.6    -2.8    119  0.6
  7000   13.4  56.1   190   14    7   5.9   3.2   20.4  68.7    -3.3    105  0.5
  6750   13.9  57.0   185   15    8   8.1   4.4   20.2  68.4    -3.5     80  0.4
  6500   14.5  58.1   175   16    8   7.5   4.1   20.1  68.1    -3.7     56  0.3
  6250   15.1  59.2   170   18    9   7.8   4.3   19.9  67.8    -3.8     32  0.2
  6000   15.6  60.1   165   20   10   7.1   3.9   19.8  67.6    -4.0      8  0.0
  5750   16.2  61.2   160   18    9   9.6   5.3   19.6  67.3    -4.2      M    M
  5500   16.8  62.2   155   14    7   0.3   0.2   19.4  67.0    -4.4      M    M
  5250   16.1  61.0   145   11    6 -13.7  -7.5   18.1  64.5    -5.8      M    M
  5000   15.1  59.2   130    9    5  -6.9  -3.8   16.4  61.6    -7.5      M    M

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

           03/22/2017 at 0900 MDT          |       03/22/2017 at 1200 MDT
                                           |
K index... +12.7  LI... +1.1               | K index... +8.5  LI... +0.9
CAPE... 0.0  CIN... 0.0                    | CAPE... +0.1  CIN... -1.7
                                           |
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 -64.0 -83.2  240  48 25   5.1   2.8 | -63.1 -81.6  240  47 24   4.8   2.6
 45000 -56.4 -69.5  245  55 28   4.6   2.5 | -56.0 -68.8  240  57 29   4.6   2.5
 40000 -49.2 -56.6  245  68 35   4.4   2.4 | -48.7 -55.7  240  75 39   4.4   2.4
 38000 -49.5 -57.1  245  74 38  -2.1  -1.2 | -49.2 -56.6  240  81 42  -3.0  -1.7
 36000 -50.8 -59.4  245  79 41  -2.1  -1.2 | -51.1 -60.0  240  86 44  -3.0  -1.7
 34000 -50.3 -58.5  240  83 43   6.9   3.8 | -51.1 -60.0  235  89 46   6.8   3.7
 32000 -46.1 -51.0  240  82 42   7.0   3.8 | -46.9 -52.4  235  87 45   7.0   3.8
 30000 -41.7 -43.1  240  82 42   8.3   4.5 | -42.4 -44.3  235  84 43   8.5   4.6
 29000 -39.2 -38.6  240  81 42   8.3   4.5 | -39.9 -39.8  235  81 42   8.5   4.6
 28000 -36.7 -34.1  240  80 41   8.3   4.5 | -36.7 -34.1  235  77 40   8.5   4.6
 27000 -33.7 -28.7  240  78 40   7.7   4.2 | -34.3 -29.7  235  74 38   7.5   4.1
 26000 -31.4 -24.5  240  73 38   7.8   4.3 | -32.0 -25.6  235  69 36   7.5   4.1
 25000 -29.1 -20.4  240  69 35   7.8   4.3 | -29.8 -21.6  235  65 33   7.5   4.1
 24000 -26.8 -16.2  240  64 33   7.2   3.9 | -27.5 -17.5  235  61 31   8.8   4.8
 23000 -24.7 -12.5  240  61 31   7.2   4.0 | -24.8 -12.6  230  60 31   8.9   4.9
 22000 -22.5  -8.5  235  58 30   7.2   4.0 | -22.2  -8.0  230  59 30   8.9   4.9
 21000 -20.5  -4.9  230  55 28   6.1   3.3 | -20.0  -4.0  230  58 30   5.1   2.8
 20000 -18.7  -1.7  230  51 26   6.2   3.4 | -18.4  -1.1  230  55 28   5.4   3.0
 19500 -17.8  -0.0  230  50 26   6.2   3.4 | -17.6   0.3  230  54 28   5.4   3.0
 19000 -16.9   1.6  230  48 25   6.2   3.4 | -16.8   1.8  235  52 27   5.4   2.9
 18500 -16.0   3.2  230  46 24   5.9   3.3 | -16.0   3.2  235  51 26   5.6   3.1
 18000 -15.1   4.8  230  44 23   6.1   3.3 | -15.1   4.8  230  48 25   5.7   3.1
 17500 -14.2   6.4  230  42 22   7.4   4.1 | -14.3   6.3  230  45 23   7.0   3.9
 17000 -12.8   9.0  230  40 21   8.9   4.9 | -13.0   8.6  230  43 22   8.9   4.9
 16500 -11.5  11.3  230  39 20   9.0   4.9 | -11.6  11.1  230  40 21   9.0   5.0
 16000 -10.2  13.6  230  36 19   7.8   4.3 | -10.4  13.3  230  37 19   7.8   4.3
 15500  -9.0  15.8  230  34 17   7.9   4.4 |  -9.1  15.6  230  34 17   7.9   4.3
 15000  -7.9  17.8  230  31 16   7.4   4.1 |  -7.9  17.8  230  31 16   8.7   4.8
 14500  -6.8  19.8  230  29 15   7.5   4.1 |  -6.5  20.3  230  29 15   8.8   4.8
 14000  -5.8  21.6  230  26 13   7.7   4.2 |  -5.2  22.6  225  28 14   7.8   4.3
 13500  -4.6  23.7  225  24 12   7.8   4.3 |  -3.7  25.3  220  26 14   7.1   3.9
 13000  -2.9  26.8  220  21 11   8.7   4.8 |  -2.6  27.3  220  25 13   7.9   4.3
 12500  -1.6  29.1  220  20 10   8.6   4.7 |  -1.5  29.3  220  24 12   7.9   4.3
 12000  -0.3  31.5  215  19 10   8.8   4.8 |  -0.4  31.3  220  23 12   8.4   4.6
 11500   1.0  33.8  215  18  9   8.9   4.9 |   0.9  33.6  215  23 12   8.5   4.7
 11000   2.2  36.0  210  17  9   7.2   3.9 |   2.1  35.8  215  24 12   7.5   4.1
 10500   3.3  37.9  210  16  8   6.3   3.5 |   3.2  37.8  215  24 12   6.8   3.7
 10250   3.8  38.8  210  15  8  10.4   5.7 |   3.7  38.7  215  24 12  10.0   5.5
 10000   4.7  40.5  210  15  8  11.3   6.2 |   4.6  40.3  215  24 12  10.6   5.8
  9750   5.4  41.7  210  15  7   7.7   4.2 |   5.2  41.4  210  24 12   7.7   4.2
  9500   6.0  42.8  215  14  7   9.0   4.9 |   5.8  42.4  210  23 12   8.6   4.7
  9250   6.6  43.9  215  14  7   7.3   4.0 |   6.4  43.5  210  23 12   7.8   4.3
  9000   7.1  44.8  210  14  7   6.7   3.7 |   7.0  44.6  210  23 12   8.2   4.5
  8750   7.7  45.9  210  14  7   7.8   4.3 |   7.6  45.7  205  22 11   8.9   4.9
  8500   8.3  46.9  210  14  7   7.4   4.1 |   8.3  46.9  205  21 11   8.7   4.8
  8250   8.8  47.8  210  14  7   8.3   4.5 |   8.9  48.0  205  20 11   8.4   4.6
  8000   9.4  48.9  205  14  7   7.3   4.0 |   9.5  49.1  200  19 10   7.5   4.1
  7750   9.9  49.8  205  15  8   6.0   3.3 |  10.0  50.0  195  17  9   6.9   3.8
  7500  10.4  50.7  200  15  8   5.4   3.0 |  10.5  50.9  190  15  8   7.6   4.2
  7250  10.7  51.3  195  15  8   4.2   2.3 |  11.1  52.0  185  14  7   9.1   5.0
  7000  11.0  51.8  190  16  8   3.4   1.9 |  11.8  53.2  185  13  7   9.7   5.3
  6750  11.2  52.2  180  16  8   3.2   1.7 |  12.5  54.5  185  13  7   9.2   5.0
  6500  11.3  52.3  175  16  8  -0.6  -0.3 |  13.2  55.8  185  13  7  10.3   5.7
  6250  11.1  52.0  170  14  7  -3.4  -1.9 |  14.1  57.4  185  12  6  11.6   6.4
  6000  10.8  51.4  160  12  6  -3.6  -2.0 |  14.9  58.8  185  12  6  10.8   5.9
  5750  10.5  50.9  145   8  4  -1.8  -1.0 |  15.7  60.3  185  11  6  10.7   5.9
  5500  10.6  51.1  125   7  3   3.5   1.9 |  16.6  61.9  185  11  6  12.5   6.8
  5250  10.9  51.6  125   6  3   4.2   2.3 |  17.5  63.5  185  11  5  14.0   7.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           03/22/2017 at 1500 MDT          |       03/22/2017 at 1800 MDT
                                           |
K index... +21.1  LI... +0.7               | K index... +17.5  LI... +1.9
CAPE... +6.6  CIN... -3.2                  | CAPE... +0.2  CIN... -0.7
                                           |
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 -62.3 -80.1  240  49 25   4.2   2.3 | -62.0 -79.6  240  54 28   3.8   2.1
 45000 -55.9 -68.6  240  62 32   4.2   2.3 | -56.3 -69.3  240  69 36   3.8   2.1
 40000 -49.3 -56.7  240  80 41   4.0   2.2 | -50.6 -59.1  235  84 43   3.8   2.1
 38000 -49.9 -57.8  235  86 44  -3.2  -1.8 | -50.2 -58.4  235  87 45  -1.5  -0.8
 36000 -51.9 -61.4  235  91 47  -3.2  -1.8 | -51.1 -60.0  230  89 46  -1.5  -0.8
 34000 -51.9 -61.4  230  93 48   7.3   4.0 | -50.6 -59.1  225  89 46   6.2   3.4
 32000 -47.4 -53.3  225  87 45   7.5   4.1 | -46.9 -52.4  220  84 43   6.3   3.4
 30000 -42.5 -44.5  225  79 41   9.6   5.3 | -42.5 -44.5  215  79 40   9.4   5.2
 29000 -39.7 -39.5  220  73 38   9.6   5.3 | -39.6 -39.3  215  74 38   9.4   5.2
 28000 -36.8 -34.2  220  67 35   9.6   5.3 | -36.8 -34.2  215  70 36   9.5   5.2
 27000 -33.3 -27.9  220  61 31   8.2   4.5 | -34.1 -29.4  220  66 34   7.8   4.3
 26000 -30.9 -23.6  220  60 31   8.3   4.5 | -31.8 -25.2  220  66 34   7.7   4.2
 25000 -28.4 -19.1  225  58 30   8.3   4.6 | -29.5 -21.1  220  66 34   7.7   4.2
 24000 -26.0 -14.8  225  57 29   6.7   3.7 | -27.2 -17.0  220  66 34   7.9   4.3
 23000 -24.1 -11.4  225  56 29   6.6   3.6 | -24.8 -12.6  225  61 31   8.0   4.4
 22000 -22.1  -7.8  225  55 29   6.6   3.6 | -22.4  -8.3  225  56 29   8.1   4.4
 21000 -20.2  -4.4  225  54 28   6.2   3.4 | -20.1  -4.2  230  52 27   5.8   3.2
 20000 -18.4  -1.1  225  51 26   6.2   3.4 | -18.5  -1.3  230  52 27   5.5   3.0
 19500 -17.5   0.5  225  50 26   6.2   3.4 | -17.7   0.1  230  52 27   5.5   3.0
 19000 -16.6   2.1  225  49 25   6.2   3.4 | -16.9   1.6  230  52 27   5.5   3.0
 18500 -15.6   3.9  225  47 24   6.8   3.7 | -16.0   3.2  230  52 27   6.8   3.8
 18000 -14.6   5.7  225  45 23   6.9   3.8 | -14.9   5.2  230  50 26   7.7   4.2
 17500 -13.6   7.5  225  43 22   6.6   3.6 | -13.8   7.2  230  47 24   7.7   4.2
 17000 -12.7   9.1  225  41 21   5.8   3.2 | -12.8   9.0  230  44 23   5.9   3.2
 16500 -11.9  10.6  225  39 20   5.9   3.2 | -11.9  10.6  230  41 21   6.0   3.3
 16000 -11.1  12.0  225  37 19   5.2   2.9 | -11.0  12.2  225  39 20   6.4   3.5
 15500 -10.3  13.5  220  34 18   5.2   2.9 |  -9.5  14.9  220  37 19   6.4   3.5
 15000  -9.4  15.1  215  31 16   6.8   3.7 |  -8.5  16.7  220  35 18   7.4   4.0
 14500  -8.3  17.1  215  30 15   7.3   4.0 |  -7.4  18.7  215  34 17   7.3   4.0
 14000  -7.3  18.9  210  29 15   8.1   4.4 |  -6.3  20.7  210  32 17   7.6   4.1
 13500  -5.3  22.5  210  28 14   8.7   4.8 |  -5.2  22.6  205  31 16   7.6   4.2
 13000  -3.9  25.0  205  27 14  10.0   5.5 |  -4.0  24.8  200  29 15   8.1   4.5
 12500  -2.4  27.7  205  27 14  10.1   5.5 |  -2.8  27.0  200  28 15   8.4   4.6
 12000  -0.9  30.4  205  26 13   9.9   5.4 |  -1.5  29.3  195  27 14   9.1   5.0
 11500   0.6  33.1  205  26 13  10.0   5.5 |  -0.1  31.8  195  27 14   9.5   5.2
 11000   2.0  35.6  205  25 13   8.6   4.7 |   1.3  34.3  195  27 14   8.9   4.9
 10500   3.2  37.8  210  24 12   8.2   4.5 |   2.6  36.7  190  27 14   7.9   4.4
 10250   3.9  39.0  210  23 12  11.6   6.3 |   3.3  37.9  190  27 14  11.4   6.2
 10000   4.8  40.6  210  23 12  11.7   6.4 |   4.2  39.6  190  27 14  11.8   6.5
  9750   5.5  41.9  210  22 12   9.3   5.1 |   4.9  40.8  190  26 14   8.7   4.8
  9500   6.3  43.3  210  22 11   9.9   5.4 |   5.6  42.1  190  26 14   9.5   5.2
  9250   7.0  44.6  210  22 11  10.0   5.5 |   6.3  43.3  190  26 13   9.4   5.2
  9000   7.7  45.9  210  21 11   9.9   5.5 |   7.1  44.8  185  26 13   9.5   5.2
  8750   8.5  47.3  210  21 11   9.8   5.4 |   7.8  46.0  185  26 13   9.6   5.2
  8500   9.2  48.6  210  21 11   9.5   5.2 |   8.5  47.3  185  25 13   9.3   5.1
  8250   9.9  49.8  210  20 11  11.1   6.1 |   9.2  48.6  185  25 13  10.3   5.6
  8000  10.8  51.4  210  20 10  10.4   5.7 |  10.0  50.0  185  25 13  10.0   5.5
  7750  11.4  52.5  210  20 10   8.3   4.6 |  10.7  51.3  185  25 13   8.8   4.8
  7500  12.1  53.8  210  20 10   9.1   5.0 |  11.3  52.3  185  24 12   9.0   4.9
  7250  12.8  55.0  210  19 10  10.7   5.9 |  12.0  53.6  185  24 12   9.7   5.3
  7000  13.7  56.7  210  19 10  10.8   5.9 |  12.8  55.0  185  23 12  10.0   5.5
  6750  14.4  57.9  210  19 10   9.2   5.1 |  13.5  56.3  180  23 12   9.1   5.0
  6500  15.1  59.2  210  18  9   9.8   5.4 |  14.2  57.6  180  22 11   9.4   5.2
  6250  15.8  60.4  210  18  9  10.7   5.9 |  14.9  58.8  180  21 11  10.7   5.8
  6000  16.6  61.9  210  17  9  10.5   5.8 |  15.7  60.3  180  20 10  10.5   5.8
  5750  17.4  63.3  210  16  8   9.9   5.4 |  16.5  61.7  180  18  9   9.2   5.1
  5500  18.1  64.6  210  15  8   8.9   4.9 |  17.1  62.8  175  16  8   6.8   3.7
  5250  18.7  65.7  210  14  7   8.3   4.5 |  17.4  63.3  180  15  8   3.7   2.0
  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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