Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 191234
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0634 MDT Monday, June 19, 2017

This forecast is for Monday, June 19, 2017:

If the trigger temperature of 79.7 F/26.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 938 ft/min (4.8 m/s)
   Maximum height of thermals.................. 16713 ft MSL (11874 ft AGL)

Forecast maximum temperature................... 97.0 F/36.6 C
Time of trigger temperature.................... 1945 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................. 14519 ft MSL (9680 ft AGL)
Thermal soaring outlook for Tuesday 06/20...... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:48:12 / 20:42:53 MDT
Total possible sunshine........... 14 hr 54 min 41 sec (894 min 41 sec)
Altitude of sun at 13:15:40 MDT... 74.28 degrees

Upper air data from rawinsonde observation taken on 06/19/2017 at 0600 MDT

Freezing level.................. 16231 ft MSL (11392 ft AGL)
Additional freezing levels...... 16635 ft MSL (11796 ft AGL)
                                 17950 ft MSL (13111 ft AGL)
Convective condensation level... 20856 ft MSL (16017 ft AGL)
Lifted condensation level....... 18760 ft MSL (13920 ft AGL)
Lifted index.................... +1.9
K index......................... +3.5

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  -71.4 -96.5   295   39   20  -2.2  -1.2   75.8 168.4    22.9      M    M
 45000  -67.0 -88.6   285   24   13  -1.9  -1.0   58.7 137.7    14.1      M    M
 40000  -54.9 -66.8   295   32   16   8.9   4.9   53.6 128.5    11.7      M    M
 38000  -49.7 -57.5   275   26   13   7.8   4.3   52.8 127.0    11.4      M    M
 36000  -45.0 -49.0   295   32   16   8.0   4.4   51.1 124.0    10.6      M    M
 34000  -40.0 -40.0   300   31   16   8.4   4.6   49.7 121.5     9.8      M    M
 32000  -34.9 -30.8   310   30   15   9.2   5.1   49.0 120.1     9.5      M    M
 30000  -29.1 -20.4   315   28   14   8.4   4.6   47.9 118.2     9.0      M    M
 29000  -26.6 -15.9   315   27   14   8.4   4.6   47.4 117.3     8.7      M    M
 28000  -24.0 -11.2   320   26   13   8.6   4.7   46.8 116.2     8.3      M    M
 27000  -21.5  -6.7   320   25   13   8.6   4.7   46.3 115.3     8.0      M    M
 26000  -18.9  -2.0   325   24   12   8.6   4.7   45.9 114.6     7.8      M    M
 25000  -16.3   2.7   325   23   12   8.1   4.5   45.6 114.1     7.6      M    M
 24000  -14.0   6.8   320   21   11   7.9   4.3   44.8 112.6     7.1      M    M
 23000  -11.6  11.1   310   19   10   7.9   4.3   44.1 111.3     6.6      M    M
 22000   -9.2  15.4   300   17    9   7.9   4.3   43.5 110.3     6.2      M    M
 21000   -6.9  19.6   290   16    8   7.9   4.3   43.0 109.4     5.8      M    M
 20000   -4.5  23.9   310   21   11   7.9   4.3   42.3 108.2     5.3      M    M
 19500   -3.3  26.1   310   21   11   7.9   4.4   42.0 107.5     5.0      M    M
 19000   -2.1  28.2   310   22   11   8.5   4.7   41.7 107.0     4.8      M    M
 18500   -0.8  30.6   310   23   12   6.5   3.6   41.4 106.6     4.6      M    M
 18000   -0.0  32.0   315   24   12   3.4   1.9   40.7 105.2     4.0      M    M
 17500    0.1  32.2   315   25   13   0.6   0.4   39.1 102.4     2.6      M    M
 17000    0.1  32.2   315   26   13   0.8   0.4   37.6  99.6     1.3      M    M
 16500   -0.4  31.3   310   22   11   2.2   1.2   34.6  94.3    -1.4    941  4.8
 16000    0.9  33.6   305   19   10   8.1   4.5   34.4  94.0    -1.6    888  4.5
 15500    2.1  35.8   315   17    9   7.0   3.8   34.2  93.5    -1.9    837  4.3
 15000    3.0  37.4   320   16    8   6.3   3.5   33.6  92.4    -2.5    796  4.0
 14500    3.8  38.8   330   14    7   6.4   3.5   33.0  91.4    -3.1    755  3.8
 14000    4.7  40.5   340   14    7   6.3   3.4   32.5  90.5    -3.7    715  3.6
 13500    5.8  42.4   330   14    7   9.5   5.2   32.1  89.8    -4.1    668  3.4
 13000    7.1  44.8   325   15    7   9.4   5.2   32.1  89.7    -4.3    612  3.1
 12500    8.5  47.3   315   15    8   9.6   5.3   32.0  89.6    -4.4    557  2.8
 12000    9.6  49.3   310   16    8   2.6   1.4   31.7  89.1    -4.8    510  2.6
 11500    9.5  49.1   310   13    6   4.3   2.4   30.2  86.4    -6.4    497  2.5
 11000   10.5  50.9   315    9    5   6.3   3.5   29.7  85.5    -6.9    452  2.3
 10500   11.4  52.5   325    6    3   1.1   0.6   29.1  84.4    -7.5    412  2.1
 10250   11.3  52.3   330    6    3   0.6   0.3   28.3  82.9    -8.3    408  2.1
 10000   11.6  52.9   340    5    3   7.9   4.3   27.9  82.2    -8.7    389  2.0
  9750   12.3  54.1   355    5    3   8.6   4.7   27.8  82.0    -8.8    363  1.8
  9500   12.9  55.2   010    6    3   8.4   4.6   27.7  81.8    -8.9    336  1.7
  9250   13.5  56.3   020    7    4   8.4   4.6   27.6  81.6    -9.0    310  1.6
  9000   14.2  57.6   030    8    4   8.7   4.8   27.5  81.5    -9.2    284  1.4
  8750   14.8  58.6   035    9    5   7.6   4.2   27.4  81.3    -9.3    257  1.3
  8500   15.3  59.5   040   11    6   5.7   3.1   27.1  80.8    -9.6    236  1.2
  8250   15.7  60.3   040   12    6   5.4   3.0   26.8  80.2    -9.9    216  1.1
  8000   16.1  61.0   045   14    7   5.5   3.0   26.5  79.6   -10.3    197  1.0
  7750   16.5  61.7   050   15    8   5.5   3.0   26.1  79.0   -10.6    178  0.9
  7500   16.9  62.4   055   16    8   5.4   2.9   25.8  78.4   -11.0    158  0.8
  7250   17.3  63.1   060   17    9   7.9   4.3   25.5  78.0   -11.3    137  0.7
  7000   18.0  64.4   065   19   10   9.8   5.4   25.5  77.9   -11.3    109  0.6
  6750   18.7  65.7   065   16    8   9.3   5.1   25.5  77.9   -11.4     81  0.4
  6500   19.4  66.9   065   12    6   9.4   5.2   25.5  77.8   -11.4     53  0.3
  6250   20.1  68.2   070    8    4   9.4   5.2   25.4  77.8   -11.5     24  0.1
  6000   20.8  69.4   070    4    2   9.4   5.2   25.4  77.8   -11.5      M    M
  5750   21.5  70.7   080    2    1   9.4   5.2   25.4  77.7   -11.6      M    M
  5500   22.2  72.0   085    1    1   9.3   5.1   25.4  77.6   -11.7      M    M
  5250   22.9  73.2   120    1    0   9.7   5.3   25.3  77.6   -11.7      M    M
  5000   23.6  74.5   205    1    0   8.4   4.6   25.3  77.5   -11.8      M    M

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

           06/19/2017 at 0900 MDT          |       06/19/2017 at 1200 MDT
                                           |
K index... +1.6  LI... +3.8                | K index... -2.0  LI... +2.7
CAPE... 0.0  CIN... -6.4                   | CAPE... +53.5  CIN... -184.2
                                           |
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 -67.9 -90.2  305  25 13   0.0   0.0 | -67.2 -89.0  315  28 14  -0.1  -0.0
 45000 -64.7 -84.5  285  30 15   6.3   3.5 | -64.3 -83.7  295  34 18   5.8   3.2
 40000 -54.8 -66.6  290  30 16   8.3   4.5 | -55.0 -67.0  285  33 17   8.3   4.6
 38000 -49.9 -57.8  300  30 16   8.3   4.5 | -50.0 -58.0  295  31 16   8.3   4.5
 36000 -44.9 -48.8  310  31 16   8.3   4.5 | -45.1 -49.2  300  30 16   8.3   4.5
 34000 -40.0 -40.0  310  28 15   8.3   4.6 | -40.1 -40.2  305  26 13   8.3   4.5
 32000 -34.4 -29.9  315  25 13   8.4   4.6 | -35.1 -31.2  305  22 11   8.4   4.6
 30000 -29.4 -20.9  310  24 12   8.3   4.6 | -29.6 -21.3  305  21 11   8.3   4.5
 29000 -26.9 -16.4  310  23 12   8.3   4.6 | -27.1 -16.8  305  20 10   8.3   4.5
 28000 -24.4 -11.9  310  23 12   8.3   4.6 | -24.6 -12.3  305  20 10   8.1   4.5
 27000 -21.9  -7.4  310  23 12   8.3   4.6 | -22.2  -8.0  305  19 10   8.2   4.5
 26000 -19.4  -2.9  310  23 12   8.3   4.6 | -19.7  -3.5  310  19 10   8.2   4.5
 25000 -17.0   1.4  305  23 12   8.1   4.4 | -17.3   0.9  310  18  9   8.0   4.4
 24000 -14.6   5.7  310  22 11   8.0   4.4 | -14.9   5.2  310  18  9   8.0   4.4
 23000 -12.2  10.0  310  21 11   8.0   4.4 | -12.5   9.5  310  17  9   8.0   4.4
 22000  -9.8  14.4  315  20 10   7.9   4.4 | -10.1  13.8  310  17  9   8.4   4.6
 21000  -7.4  18.7  315  20 10   7.9   4.3 |  -7.5  18.5  315  17  9   8.4   4.6
 20000  -5.1  22.8  320  21 11   7.9   4.3 |  -5.0  23.0  320  17  9   8.4   4.6
 19500  -3.9  25.0  320  21 11   7.8   4.3 |  -3.8  25.2  320  17  9   8.0   4.4
 19000  -2.9  26.8  320  21 11   6.1   3.3 |  -2.7  27.1  325  16  8   7.0   3.8
 18500  -1.9  28.6  320  21 11   6.2   3.4 |  -1.6  29.1  325  16  8   7.1   3.9
 18000  -0.7  30.7  320  21 11   4.3   2.3 |  -0.6  30.9  325  16  8   5.8   3.2
 17500  -0.0  32.0  320  20 10   4.5   2.5 |   0.2  32.4  325  15  8   5.5   3.0
 17000   0.6  33.1  320  19 10   4.3   2.4 |   1.0  33.8  330  14  7   5.4   3.0
 16500   1.2  34.2  320  18  9   4.3   2.3 |   1.8  35.2  330  14  7   5.0   2.8
 16000   1.9  35.4  320  17  9   4.5   2.5 |   2.5  36.5  330  13  6   5.0   2.8
 15500   2.7  36.9  320  16  8   6.4   3.5 |   3.3  37.9  330  12  6   5.3   2.9
 15000   3.6  38.5  320  16  8   6.2   3.4 |   4.0  39.2  325  11  6   5.3   2.9
 14500   4.5  40.1  320  15  8   6.8   3.7 |   5.3  41.5  325  10  5   6.9   3.8
 14000   5.5  41.9  315  15  8   7.0   3.8 |   6.3  43.3  325  10  5   6.8   3.7
 13500   6.4  43.5  315  14  7   7.1   3.9 |   7.3  45.1  320  10  5   6.7   3.7
 13000   7.3  45.1  315  13  7   7.3   4.0 |   8.2  46.8  320   9  5   7.0   3.8
 12500   8.2  46.8  315  12  6   6.9   3.8 |   9.2  48.6  320   9  5   7.3   4.0
 12000   9.0  48.2  315   9  5   6.4   3.5 |  10.1  50.2  320   8  4   7.6   4.2
 11500   9.8  49.6  320   7  4   6.6   3.6 |  11.1  52.0  320   6  3   7.4   4.0
 11000  10.8  51.4  325   5  3   6.5   3.6 |  12.0  53.6  330   5  2   7.4   4.0
 10500  11.7  53.1  335   3  2   2.5   1.4 |  12.8  55.0  345   3  2   3.2   1.8
 10250  11.8  53.2  345   3  2   4.3   2.4 |  13.0  55.4  355   3  2   5.8   3.2
 10000  12.5  54.5  360   3  2  11.1   6.1 |  13.6  56.5  010   3  2   9.6   5.2
  9750  13.2  55.8  015   4  2  10.2   5.6 |  14.2  57.6  020   4  2   8.5   4.7
  9500  13.9  57.0  025   5  3   8.1   4.5 |  14.8  58.6  030   4  2   7.2   3.9
  9250  14.4  57.9  035   7  3   4.9   2.7 |  15.3  59.5  030   4  2   7.6   4.2
  9000  14.8  58.6  040   9  5   5.2   2.9 |  16.0  60.8  030   4  2   9.8   5.4
  8750  15.1  59.2  045  11  6   5.2   2.9 |  16.7  62.1  035   5  2   9.7   5.3
  8500  15.5  59.9  050  14  7   4.9   2.7 |  17.4  63.3  035   5  2   9.6   5.2
  8250  15.8  60.4  055  15  8   4.3   2.3 |  18.1  64.6  035   5  2   9.5   5.2
  8000  16.2  61.2  060  15  8   5.4   3.0 |  18.8  65.8  035   5  2   9.6   5.3
  7750  16.6  61.9  060  16  8   7.1   3.9 |  19.5  67.1  035   5  2   9.8   5.4
  7500  17.2  63.0  060  15  8   7.8   4.3 |  20.2  68.4  035   5  2   9.8   5.4
  7250  17.8  64.0  060  14  7   8.0   4.4 |  21.0  69.8  035   5  2   9.9   5.4
  7000  18.4  65.1  060  13  7   8.5   4.7 |  21.7  71.1  035   5  2   9.8   5.4
  6750  19.0  66.2  060  12  6   8.5   4.7 |  22.5  72.5  035   5  2  10.8   5.9
  6500  19.6  67.3  060  11  5   7.0   3.8 |  23.3  73.9  035   4  2  11.5   6.3
  6250  20.2  68.4  055   9  5   6.5   3.6 |  24.2  75.6  035   4  2  11.5   6.3
  6000  20.7  69.3  055   8  4   6.4   3.5 |  25.0  77.0  035   4  2  10.9   6.0
  5750  21.4  70.5  055   8  4  13.0   7.2 |  25.9  78.6  035   4  2  13.9   7.6
  5500  22.8  73.0  055   7  4  24.7  13.6 |  27.1  80.8  035   4  2  17.4   9.6
  5250     M     M    M   M  M     M     M |  28.3  82.9  030   4  2  14.7   8.1
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           06/19/2017 at 1500 MDT          |       06/19/2017 at 1800 MDT
                                           |
K index... -9.1  LI... +2.9                | K index... -11.4  LI... +3.5
CAPE... +42.1  CIN... -120.2               | CAPE... +35.0  CIN... -44.5
                                           |
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 -66.7 -88.1  320  26 13   1.0   0.5 | -66.9 -88.4  315  28 14   1.7   0.9
 45000 -63.3 -81.9  305  36 18   4.8   2.6 | -62.8 -81.0  305  36 19   4.8   2.7
 40000 -55.3 -67.5  285  34 18   8.1   4.5 | -54.4 -65.9  285  37 19   7.8   4.3
 38000 -50.5 -58.9  285  32 16   8.1   4.4 | -49.7 -57.5  285  35 18   7.8   4.3
 36000 -45.6 -50.1  290  29 15   8.3   4.5 | -45.1 -49.2  285  32 17   8.4   4.6
 34000 -40.4 -40.7  285  27 14   8.6   4.7 | -39.9 -39.8  280  30 16   8.6   4.7
 32000 -34.6 -30.3  280  24 12   8.6   4.7 | -34.7 -30.5  275  29 15   8.7   4.8
 30000 -29.7 -21.5  290  21 11   8.3   4.5 | -29.8 -21.6  275  27 14   8.3   4.5
 29000 -27.2 -17.0  290  21 11   8.3   4.5 | -27.3 -17.1  280  26 13   8.3   4.5
 28000 -24.7 -12.5  295  19 10   8.1   4.4 | -24.8 -12.6  280  24 12   7.8   4.3
 27000 -22.3  -8.1  300  18  9   8.1   4.4 | -22.5  -8.5  285  21 11   7.9   4.3
 26000 -19.9  -3.8  305  17  9   8.1   4.5 | -19.6  -3.3  290  17  9   7.9   4.3
 25000 -17.4   0.7  310  16  8   8.1   4.4 | -17.2   1.0  295  15  8   8.3   4.6
 24000 -15.0   5.0  310  16  8   8.0   4.4 | -14.7   5.5  300  14  7   8.3   4.5
 23000 -12.6   9.3  310  15  8   8.0   4.4 | -12.2  10.0  305  14  7   8.3   4.5
 22000 -10.1  13.8  315  15  8   8.4   4.6 |  -9.8  14.4  310  13  7   8.2   4.5
 21000  -7.6  18.3  320  15  8   8.4   4.6 |  -7.3  18.9  315  13  6   8.2   4.5
 20000  -5.1  22.8  320  14  7   8.4   4.6 |  -4.9  23.2  320  12  6   8.2   4.5
 19500  -3.8  25.2  325  14  7   8.3   4.5 |  -3.7  25.3  320  11  6   8.2   4.5
 19000  -2.6  27.3  325  13  7   8.0   4.4 |  -2.4  27.7  325  11  6   8.3   4.5
 18500  -1.4  29.5  330  13  6   8.1   4.4 |  -1.2  29.8  325  10  5   8.3   4.6
 18000  -0.3  31.5  330  12  6   6.9   3.8 |   0.0  32.0  325   9  5   7.6   4.1
 17500   0.7  33.3  330  11  6   6.7   3.7 |   1.2  34.2  325   9  5   7.6   4.1
 17000   1.8  35.2  330  10  5   6.5   3.6 |   2.3  36.1  320   8  4   7.2   3.9
 16500   2.7  36.9  330   9  5   6.0   3.3 |   3.3  37.9  320   8  4   6.6   3.6
 16000   3.6  38.5  330   8  4   6.2   3.4 |   4.3  39.7  320   7  4   6.6   3.6
 15500   4.4  39.9  330   7  4   5.2   2.8 |   5.2  41.4  320   7  4   6.1   3.4
 15000   5.6  42.1  330   6  3   5.3   2.9 |   6.1  43.0  320   6  3   6.2   3.4
 14500   6.5  43.7  330   5  3   7.1   3.9 |   7.0  44.6  325   5  3   6.9   3.8
 14000   7.5  45.5  325   4  2   6.9   3.8 |   8.1  46.6  325   4  2   7.2   3.9
 13500   8.6  47.5  325   4  2   7.4   4.1 |   9.1  48.4  325   4  2   7.6   4.1
 13000   9.6  49.3  325   4  2   7.5   4.1 |  10.8  51.4  345   4  2   8.0   4.4
 12500  10.7  51.3  330   3  2   7.7   4.2 |  11.9  53.4  355   4  2   8.1   4.4
 12000  11.8  53.2  330   3  2   7.7   4.2 |  13.1  55.6  005   4  2   8.1   4.4
 11500  13.0  55.4  330   3  2   7.9   4.3 |  14.3  57.7  015   5  2   8.2   4.5
 11000  14.1  57.4  340   3  2   8.2   4.5 |  15.4  59.7  025   4  2   8.7   4.8
 10500  15.1  59.2  345   3  2   4.5   2.5 |  16.4  61.5  030   4  2   5.1   2.8
 10250  15.4  59.7  350   3  2   7.5   4.1 |  16.9  62.4  030   4  2   8.9   4.9
 10000  16.1  61.0  350   3  2  10.8   5.9 |  17.6  63.7  035   5  2  10.4   5.7
  9750  16.8  62.2  355   3  2  10.2   5.6 |  18.4  65.1  035   5  2  10.0   5.5
  9500  17.4  63.3  360   3  2   7.3   4.0 |  19.1  66.4  040   5  2   8.1   4.4
  9250  17.8  64.0  355   3  2   7.5   4.1 |  19.6  67.3  040   4  2   7.7   4.2
  9000  18.5  65.3  360   3  2  10.5   5.7 |  20.2  68.4  040   4  2   8.9   4.9
  8750  19.1  66.4  360   3  2  10.0   5.5 |  20.7  69.3  040   4  2   8.6   4.7
  8500  19.8  67.6  360   3  2   9.7   5.3 |  21.3  70.3  040   4  2   8.7   4.7
  8250  20.5  68.9  355   3  2   9.5   5.2 |  21.9  71.4  040   3  2   8.8   4.8
  8000  21.2  70.2  355   3  2  10.0   5.5 |  22.6  72.7  040   3  2   9.2   5.1
  7750  21.9  71.4  355   3  1  10.1   5.6 |  23.2  73.8  040   3  2   9.5   5.2
  7500  22.7  72.9  355   3  1   9.9   5.4 |  23.9  75.0  040   3  2   9.8   5.4
  7250  23.4  74.1  350   3  1   9.9   5.4 |  24.6  76.3  040   3  1   9.6   5.3
  7000  24.1  75.4  350   3  1   9.9   5.4 |  25.4  77.7  040   3  1  10.4   5.7
  6750  24.9  76.8  350   2  1  10.8   5.9 |  26.2  79.2  040   2  1  11.1   6.1
  6500  25.7  78.3  350   2  1  11.4   6.3 |  27.0  80.6  045   2  1  10.6   5.8
  6250  26.6  79.9  345   2  1  11.5   6.3 |  27.8  82.0  045   2  1  11.0   6.0
  6000  27.4  81.3  345   2  1  10.7   5.9 |  28.5  83.3  045   2  1   9.7   5.3
  5750  28.3  82.9  340   2  1  13.8   7.6 |  29.3  84.7  045   2  1  10.2   5.6
  5500  29.5  85.1  340   2  1  17.6   9.6 |  30.1  86.2  040   2  1  12.2   6.7
  5250  30.7  87.3  345   2  1  14.7   8.0 |  31.0  87.8  035   2  1  10.6   5.8
  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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