Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 221228
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0628 MDT Tuesday, May 22, 2018

This forecast is for Tuesday, May 22, 2018:

If the trigger temperature of 73.8 F/23.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 589 ft/min (3.0 m/s)
   Maximum height of thermals.................. 12832 ft MSL (7993 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7153 ft MSL (2314 ft AGL)
Thermal soaring outlook for Wednesday 05/23.... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:55:39 / 20:25:50 MDT
Total possible sunshine........... 14 hr 30 min 10 sec (870 min 10 sec)
Altitude of sun at 13:10:56 MDT... 71.35 degrees

Upper air data from rawinsonde observation taken on 05/22/2018 at 0600 MDT

Freezing level.................. 13552 ft MSL (8713 ft AGL)
Convective condensation level... 16613 ft MSL (11774 ft AGL)
Lifted condensation level....... 15550 ft MSL (10711 ft AGL)
Lifted index.................... -1.9
K index......................... +20.9

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  -59.2 -74.6   220   15    8  -6.4  -3.5  101.0 213.8    43.5      M    M
 45000  -64.0 -83.2   200   54   28  -8.0  -4.4   67.2 153.0    26.0      M    M
 40000  -60.8 -77.4   205   62   32   6.7   3.7   49.2 120.6    16.0      M    M
 38000  -56.5 -69.7   200   68   35   7.0   3.8   47.0 116.5    14.9      M    M
 36000  -52.0 -61.6   205   65   33   8.4   4.6   44.9 112.9    13.9      M    M
 34000  -47.2 -53.0   205   62   32   7.3   4.0   43.4 110.1    13.1      M    M
 32000  -42.1 -43.8   200   58   30   8.2   4.5   41.5 106.6    12.1      M    M
 30000  -37.2 -35.0   200   54   28   8.0   4.4   40.2 104.4    11.4      M    M
 29000  -34.8 -30.6   205   53   27   8.0   4.4   39.5 103.1    11.0      M    M
 28000  -32.4 -26.3   205   53   27   7.4   4.1   38.8 101.9    10.6      M    M
 27000  -31.0 -23.8   210   52   27   5.5   3.0   36.9  98.5     9.3      M    M
 26000  -29.0 -20.2   210   52   27   7.6   4.2   35.8  96.4     8.5      M    M
 25000  -26.8 -16.2   205   46   24   7.6   4.1   35.0  94.9     7.9      M    M
 24000  -24.5 -12.1   205   38   20   7.4   4.1   34.1  93.3     7.2      M    M
 23000  -24.6 -12.3   200   29   15   3.0   1.6   30.4  86.7     4.3      M    M
 22000  -22.4  -8.3   185   19   10   7.3   4.0   29.5  85.1     3.6      M    M
 21000  -20.4  -4.7   190   21   11   9.4   5.2   28.5  83.3     2.8      M    M
 20000  -17.5   0.5   190   23   12   9.5   5.2   28.4  83.1     2.7      M    M
 19500  -16.1   3.0   185   21   11   9.5   5.2   28.3  83.0     2.7      M    M
 19000  -14.7   5.5   180   19   10   9.5   5.2   28.3  82.9     2.6      M    M
 18500  -13.3   8.1   175   18    9   9.6   5.3   28.2  82.8     2.6      M    M
 18000  -11.8  10.8   170   18    9   9.5   5.2   28.2  82.8     2.6      M    M
 17500   -9.7  14.5   165   17    9   9.9   5.4   28.2  82.8     2.6      M    M
 17000   -8.2  17.2   160   17    9   9.9   5.4   28.2  82.8     2.6      M    M
 16500   -6.7  19.9   155   18    9   9.9   5.4   28.3  82.9     2.7      M    M
 16000   -5.2  22.6   150   18    9   9.8   5.4   28.3  83.0     2.7      M    M
 15500   -3.8  25.2   150   18    9   9.0   5.0   28.3  83.0     2.7      M    M
 15000   -2.7  27.1   145   17    9   8.2   4.5   28.0  82.5     2.4      M    M
 14500   -1.6  29.1   145   17    9   6.3   3.5   27.7  81.8     2.0      M    M
 14000   -0.7  30.7   145   17    9   6.2   3.4   27.1  80.7     1.5      M    M
 13500    0.2  32.4   155   16    8   5.4   3.0   26.4  79.6     0.9      M    M
 13000    0.9  33.6   165   16    8   6.0   3.3   25.8  78.4     0.1      M    M
 12500    1.8  35.2   170   16    8   8.0   4.4   25.3  77.6    -0.4    657  3.3
 12000    3.0  37.4   180   16    8   8.0   4.4   25.0  77.0    -0.7    608  3.1
 11500    4.1  39.4   185   16    8   8.0   4.4   24.7  76.5    -1.0    558  2.8
 11000    5.3  41.5   195   16    8   8.0   4.4   24.4  76.0    -1.3    508  2.6
 10500    6.6  43.9   200   17    9   9.2   5.0   24.3  75.7    -1.4    455  2.3
 10250    7.3  45.1   205   17    9   9.0   5.0   24.2  75.6    -1.5    427  2.2
 10000    8.0  46.4   205   16    8   9.2   5.0   24.2  75.5    -1.6    399  2.0
  9750    8.7  47.7   200   15    8   9.2   5.0   24.1  75.4    -1.6    371  1.9
  9500    9.4  48.9   200   14    7   9.2   5.0   24.1  75.4    -1.6    343  1.7
  9250   10.1  50.2   195   12    6   9.2   5.0   24.1  75.3    -1.6    314  1.6
  9000   10.8  51.4   190   11    6   9.2   5.0   24.0  75.2    -1.7    286  1.5
  8750   11.4  52.5   185   11    6   9.2   5.0   24.0  75.1    -1.7    258  1.3
  8500   12.1  53.8   175   12    6   9.2   5.1   23.9  75.1    -1.8    229  1.2
  8250   12.8  55.0   170   12    6   9.1   5.0   23.9  75.0    -1.8    201  1.0
  8000   13.5  56.3   165   13    7   9.5   5.2   23.8  74.9    -1.8    173  0.9
  7750   14.2  57.6   160   12    6   8.2   4.5   23.8  74.8    -1.9    144  0.7
  7500   14.7  58.5   155   10    5   5.3   2.9   23.5  74.4    -2.1    122  0.6
  7250   15.0  59.0   145    8    4   2.9   1.6   23.1  73.6    -2.6    107  0.5
  7000   15.0  59.0   135    7    4  -3.3  -1.8   22.4  72.3    -3.3     99  0.5
  6750   14.7  58.5   135    8    4   0.7   0.4   21.4  70.5    -4.3    100  0.5
  6500   15.2  59.4   140   10    5   7.3   4.0   21.1  69.9    -4.6     80  0.4
  6250   15.6  60.1   145   12    6   5.5   3.0   20.8  69.4    -4.9     59  0.3
  6000   16.0  60.8   150   13    7   6.1   3.3   20.5  68.9    -5.2     39  0.2
  5750   16.5  61.7   145   12    6   5.8   3.2   20.2  68.4    -5.5     18  0.1
  5500   16.8  62.2   135   10    5   2.7   1.5   19.8  67.7    -5.9      1  0.0
  5250   16.9  62.4   120    9    4   0.6   0.3   19.2  66.5    -6.6      M    M
  5000   17.0  62.6   100    8    4   1.1   0.6   18.5  65.3    -7.3      M    M

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

           05/22/2018 at 0900 MDT          |       05/22/2018 at 1200 MDT
                                           |
K index... +24.0  LI... -3.6               | K index... +30.9  LI... -2.2
CAPE... +469.2  CIN... -10.1               | CAPE... +287.2  CIN... -11.3
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -60.6 -77.1  200  24 12  -0.6  -0.3 | -59.0 -74.2  205  25 13   0.6   0.3
 45000 -61.1 -78.0  210  37 19   1.4   0.7 | -58.3 -72.9  210  35 18  -0.2  -0.1
 40000 -59.0 -74.2  200  64 33   1.3   0.7 | -58.7 -73.7  200  75 39  -1.1  -0.6
 38000 -55.2 -67.4  200  68 35   7.6   4.2 | -55.1 -67.2  195  79 41   6.9   3.8
 36000 -50.6 -59.1  200  70 36   7.6   4.2 | -51.0 -59.8  195  81 42   6.9   3.8
 34000 -46.4 -51.5  200  70 36   6.4   3.5 | -47.1 -52.8  195  80 41   6.4   3.5
 32000 -42.0 -43.6  200  66 34   6.4   3.5 | -43.2 -45.8  195  74 38   6.4   3.5
 30000 -38.1 -36.6  205  60 31   6.8   3.7 | -39.1 -38.4  195  65 33   7.7   4.2
 29000 -36.0 -32.8  205  56 29   6.8   3.7 | -36.8 -34.2  190  57 29   7.7   4.2
 28000 -34.0 -29.2  205  52 27   6.8   3.8 | -34.5 -30.1  190  50 26   7.7   4.2
 27000 -31.9 -25.4  205  49 25   7.4   4.1 | -32.1 -25.8  185  45 23   8.6   4.7
 26000 -29.6 -21.3  205  46 24   7.4   4.1 | -29.0 -20.2  185  42 22   8.5   4.7
 25000 -27.4 -17.3  200  44 22   7.5   4.1 | -26.5 -15.7  180  41 21   8.5   4.7
 24000 -25.2 -13.4  195  41 21   7.3   4.0 | -24.1 -11.4  180  39 20   7.3   4.0
 23000 -23.0  -9.4  190  38 19   7.4   4.0 | -21.9  -7.4  180  37 19   7.4   4.1
 22000 -20.8  -5.4  185  35 18   7.4   4.0 | -19.7  -3.5  175  34 18   7.4   4.0
 21000 -18.7  -1.7  180  32 16   6.6   3.6 | -17.7   0.1  175  32 17   6.5   3.6
 20000 -16.8   1.8  175  28 14   6.6   3.6 | -15.8   3.6  175  31 16   6.5   3.6
 19500 -15.8   3.6  170  26 13   6.6   3.6 | -14.8   5.4  180  30 15   6.5   3.6
 19000 -14.8   5.4  165  24 12   6.5   3.6 | -13.9   7.0  180  29 15   6.5   3.6
 18500 -13.7   7.3  165  23 12   8.8   4.8 | -12.9   8.8  180  28 14   7.2   3.9
 18000 -12.4   9.7  160  23 12   8.6   4.7 | -11.8  10.8  180  28 14   7.2   3.9
 17500 -11.2  11.8  160  23 12   8.9   4.9 | -10.8  12.6  185  27 14   7.1   3.9
 17000  -9.8  14.4  160  23 12   9.0   5.0 |  -9.8  14.4  185  27 14   7.1   3.9
 16500  -8.5  16.7  160  23 12   9.0   4.9 |  -8.7  16.3  185  27 14   7.1   3.9
 16000  -7.2  19.0  160  23 12   8.5   4.7 |  -7.7  18.1  185  28 14   7.3   4.0
 15500  -5.3  22.5  165  23 12   8.1   4.4 |  -6.7  19.9  185  28 14   7.2   4.0
 15000  -4.2  24.4  165  24 12   7.2   4.0 |  -5.6  21.9  185  27 14   7.5   4.1
 14500  -3.1  26.4  170  24 12   7.2   4.0 |  -4.5  23.9  185  27 14   7.5   4.1
 14000  -2.0  28.4  170  23 12   6.8   3.7 |  -3.5  25.7  185  26 14   7.3   4.0
 13500  -1.0  30.2  170  21 11   6.9   3.8 |  -2.4  27.7  185  26 13   7.3   4.0
 13000  -0.0  32.0  175  20 10   6.6   3.6 |  -0.9  30.4  185  25 13   7.6   4.2
 12500   1.0  33.8  175  17  9   6.5   3.6 |   0.2  32.4  185  24 12   7.5   4.1
 12000   1.9  35.4  180  15  8   7.3   4.0 |   1.4  34.5  190  23 12   8.9   4.9
 11500   3.0  37.4  185  13  7   7.3   4.0 |   2.7  36.9  190  22 11   9.0   4.9
 11000   4.0  39.2  195  12  6   7.2   3.9 |   3.9  39.0  190  20 11   7.0   3.9
 10500   5.0  41.0  200  11  6   7.0   3.8 |   4.9  40.8  190  19 10   7.7   4.2
 10250   5.6  42.1  205  11  6  11.2   6.1 |   5.5  41.9  190  19 10   9.6   5.3
 10000   6.5  43.7  210  12  6  12.0   6.6 |   6.3  43.3  190  18  9   8.6   4.7
  9750   7.2  45.0  210  13  7   8.9   4.9 |   6.8  44.2  190  18  9   7.3   4.0
  9500   7.9  46.2  210  14  7  10.6   5.8 |   7.4  45.3  190  17  9   7.8   4.3
  9250   8.6  47.5  215  14  7   7.2   4.0 |   8.0  46.4  190  16  8   7.1   3.9
  9000   9.0  48.2  215  15  8   7.2   3.9 |   8.5  47.3  185  16  8   7.0   3.8
  8750   9.6  49.3  215  15  8  10.2   5.6 |   9.0  48.2  185  15  8   7.5   4.1
  8500  10.3  50.5  215  16  8   9.4   5.2 |   9.6  49.3  180  14  7   7.4   4.0
  8250  10.9  51.6  215  16  8   8.9   4.9 |  10.1  50.2  180  13  7   6.8   3.8
  8000  11.5  52.7  210  16  8   7.3   4.0 |  10.6  51.1  175  12  6   6.7   3.7
  7750  12.0  53.6  210  14  7   6.8   3.7 |  11.1  52.0  170  10  5   6.6   3.6
  7500  12.5  54.5  210  13  7   6.6   3.6 |  11.6  52.9  160   8  4   7.5   4.1
  7250  13.0  55.4  205  11  6   5.8   3.2 |  12.2  54.0  155   8  4   9.9   5.4
  7000  13.5  56.3  200   9  5   5.4   3.0 |  12.9  55.2  155   7  4  10.1   5.5
  6750  13.9  57.0  195   8  4   4.2   2.3 |  13.6  56.5  150   7  3   8.8   4.8
  6500  14.3  57.7  190   6  3   6.7   3.7 |  14.3  57.7  150   7  3   9.9   5.4
  6250  15.0  59.0  190   6  3   9.4   5.1 |  15.1  59.2  150   6  3  11.2   6.1
  6000  15.6  60.1  185   6  3   8.9   4.9 |  15.9  60.6  150   6  3  10.5   5.8
  5750  16.4  61.5  185   5  3  10.4   5.7 |  16.7  62.1  150   6  3  11.8   6.5
  5500  17.2  63.0  185   5  3  11.6   6.4 |  17.7  63.9  150   6  3  14.6   8.0
  5250  18.1  64.6  185   5  2  11.6   6.4 |  18.8  65.8  150   6  3  15.8   8.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/22/2018 at 1500 MDT          |       05/22/2018 at 1800 MDT
                                           |
K index... +24.5  LI... -4.3               | K index... +29.6  LI... -2.9
CAPE... +781.7  CIN... -30.4               | CAPE... +518.4  CIN... -117.0
                                           |
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 -58.6 -73.5  215  23 12   0.9   0.5 | -57.6 -71.7  220  18  9   0.9   0.5
 45000 -57.5 -71.5  210  32 16   0.1   0.1 | -56.3 -69.3  215  25 13   1.3   0.7
 40000 -57.3 -71.1  195  69 35  -0.4  -0.2 | -54.2 -65.6  200  54 28   1.2   0.7
 38000 -54.2 -65.6  195  75 38   6.0   3.3 | -52.8 -63.0  200  59 31   2.5   1.4
 36000 -50.6 -59.1  190  79 41   6.0   3.3 | -51.4 -60.5  200  64 33   2.5   1.4
 34000 -46.9 -52.4  195  79 41   6.6   3.6 | -48.7 -55.7  200  65 34   7.0   3.9
 32000 -43.0 -45.4  200  72 37   6.6   3.6 | -44.6 -48.3  205  63 32   7.0   3.8
 30000 -39.0 -38.2  200  65 33   6.8   3.7 | -40.3 -40.5  205  59 30   7.3   4.0
 29000 -36.9 -34.4  200  60 31   6.8   3.7 | -38.1 -36.6  205  55 28   7.3   4.0
 28000 -34.9 -30.8  200  55 28   6.8   3.7 | -35.9 -32.6  205  52 27   7.3   4.0
 27000 -32.3 -26.1  200  49 25   7.1   3.9 | -33.1 -27.6  205  48 25   7.9   4.3
 26000 -30.2 -22.4  195  46 24   7.1   3.9 | -30.8 -23.4  205  45 23   7.9   4.3
 25000 -28.1 -18.6  190  43 22   7.2   3.9 | -28.4 -19.1  205  43 22   7.9   4.3
 24000 -25.8 -14.4  190  40 21   8.7   4.8 | -26.1 -15.0  200  41 21   7.6   4.2
 23000 -23.3  -9.9  190  39 20   8.7   4.7 | -23.8 -10.8  200  40 21   7.7   4.2
 22000 -20.7  -5.3  190  38 19   8.6   4.7 | -21.5  -6.7  200  40 20   7.7   4.2
 21000 -18.4  -1.1  190  37 19   6.9   3.8 | -19.2  -2.6  195  39 20   8.0   4.4
 20000 -16.4   2.5  190  38 20   6.9   3.8 | -16.9   1.6  195  38 20   8.0   4.4
 19500 -15.4   4.3  190  39 20   6.9   3.8 | -15.7   3.7  195  37 19   8.0   4.4
 19000 -14.3   6.3  190  39 20   6.9   3.8 | -14.5   5.9  195  37 19   8.0   4.4
 18500 -13.4   7.9  185  39 20   6.3   3.5 | -13.4   7.9  195  37 19   8.1   4.5
 18000 -12.4   9.7  185  39 20   6.4   3.5 | -12.2  10.0  195  36 19   8.2   4.5
 17500 -11.4  11.5  180  40 20   7.4   4.1 | -11.0  12.2  190  36 18   7.8   4.3
 17000 -10.2  13.6  180  39 20   7.8   4.3 |  -9.9  14.2  190  34 18   7.7   4.2
 16500  -9.0  15.8  180  39 20   8.1   4.4 |  -8.8  16.2  190  33 17   7.9   4.3
 16000  -7.7  18.1  180  39 20   9.2   5.0 |  -7.6  18.3  190  32 16   8.7   4.8
 15500  -6.4  20.5  180  39 20   9.2   5.1 |  -6.3  20.7  190  30 16   8.6   4.7
 15000  -5.1  22.8  180  38 20   8.8   4.8 |  -5.0  23.0  190  29 15   9.1   5.0
 14500  -3.9  25.0  180  37 19   8.9   4.9 |  -3.7  25.3  185  28 15   9.1   5.0
 14000  -2.6  27.3  180  36 18   8.8   4.8 |  -2.4  27.7  185  28 14   9.3   5.1
 13500  -1.4  29.5  185  33 17   8.8   4.8 |  -1.0  30.2  185  27 14   9.3   5.1
 13000   0.5  32.9  185  30 15   9.1   5.0 |   1.0  33.8  185  26 13   8.6   4.7
 12500   1.8  35.2  185  28 14   9.2   5.1 |   2.3  36.1  185  24 12   8.7   4.8
 12000   3.1  37.6  180  26 14   8.7   4.8 |   3.5  38.3  185  22 11   8.0   4.4
 11500   4.3  39.7  180  25 13   8.9   4.9 |   4.7  40.5  190  20 10   8.2   4.5
 11000   5.5  41.9  180  23 12   7.5   4.1 |   5.8  42.4  190  17  9   6.0   3.3
 10500   6.6  43.9  180  21 11   8.7   4.8 |   6.6  43.9  195  14  7   6.3   3.5
 10250   7.3  45.1  180  20 10   9.8   5.4 |   7.1  44.8  195  13  7   8.5   4.6
 10000   7.9  46.2  180  18  9   7.2   3.9 |   7.7  45.9  200  12  6   7.4   4.0
  9750   8.3  46.9  180  16  8   5.9   3.2 |   8.1  46.6  210  10  5   5.4   3.0
  9500   8.8  47.8  180  15  8   6.5   3.6 |   8.6  47.5  215   9  5   6.0   3.3
  9250   9.2  48.6  180  13  7   5.3   2.9 |   9.0  48.2  230   8  4   5.6   3.0
  9000   9.5  49.1  180  10  5   5.7   3.1 |   9.3  48.7  245   8  4   5.2   2.9
  8750  10.0  50.0  180   8  4   7.2   4.0 |   9.7  49.5  260   9  5   5.3   2.9
  8500  10.5  50.9  180   5  3   6.6   3.6 |  10.1  50.2  275  10  5   5.4   3.0
  8250  11.0  51.8  185   3  2   8.7   4.8 |  10.4  50.7  280  12  6   4.7   2.6
  8000  11.7  53.1  185   3  2   9.8   5.4 |  10.7  51.3  285  14  7   3.9   2.1
  7750  12.4  54.3  190   3  2   9.0   4.9 |  10.9  51.6  290  16  8   3.7   2.0
  7500  13.1  55.6  195   3  1   9.5   5.2 |  11.2  52.2  290  18  9   4.4   2.4
  7250  13.8  56.8  200   3  1  10.8   5.9 |  11.6  52.9  290  19 10   6.1   3.3
  7000  14.6  58.3  200   2  1  10.6   5.8 |  12.1  53.8  290  20 10   7.7   4.2
  6750  15.4  59.7  205   2  1   9.0   4.9 |  12.6  54.7  290  21 11   8.3   4.5
  6500  16.0  60.8  210   2  1  10.3   5.6 |  13.3  55.9  290  21 11   9.9   5.4
  6250  16.9  62.4  215   2  1  12.1   6.7 |  14.1  57.4  290  21 11  11.3   6.2
  6000  17.8  64.0  220   2  1  11.3   6.2 |  14.9  58.8  290  20 10  11.2   6.1
  5750  18.6  65.5  230   2  1  11.2   6.1 |  15.7  60.3  290  19 10  11.8   6.5
  5500  19.5  67.1  235   2  1  15.3   8.4 |  16.7  62.1  290  18  9  12.8   7.0
  5250  20.9  69.6  235   2  1  20.1  11.0 |  17.6  63.7  285  17  9  13.3   7.3
  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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