Soaring Guidance
Issued by NWS Grand Junction, CO

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UXUS97 KGJT 231218
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0618 MDT Friday, June 23, 2017

This forecast is for Friday, June 23, 2017:

If the trigger temperature of 80.6 F/27.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 884 ft/min (4.5 m/s)
   Maximum height of thermals.................. 15624 ft MSL (10785 ft AGL)

Forecast maximum temperature................... 93.0 F/34.3 C
Time of trigger temperature.................... 1045 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................. 13125 ft MSL (8286 ft AGL)
Thermal soaring outlook for Saturday 06/24..... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:49:05 / 20:43:44 MDT
Total possible sunshine........... 14 hr 54 min 39 sec (894 min 39 sec)
Altitude of sun at 13:16:31 MDT... 74.26 degrees

Upper air data from rawinsonde observation taken on 06/23/2017 at 0600 MDT

Freezing level.................. 16161 ft MSL (11322 ft AGL)
Convective condensation level... 21704 ft MSL (16865 ft AGL)
Lifted condensation level....... 19956 ft MSL (15116 ft AGL)
Lifted index.................... +2.0
K index......................... -6.5

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  -62.5 -80.5   300   30   15   6.7   3.7   91.3 196.4    33.2      M    M
 45000  -59.9 -75.8   290   60   31   8.2   4.5   69.9 157.8    22.4      M    M
 40000  -54.3 -65.7   285   59   30   2.0   1.1   56.0 132.8    14.7      M    M
 38000  -51.5 -60.7   290   59   31   7.5   4.1   51.2 124.2    11.9      M    M
 36000  -47.0 -52.6   295   60   31   7.5   4.1   49.4 120.8    10.8      M    M
 34000  -42.3 -44.1   295   58   30   7.0   3.8   47.8 118.1    10.0      M    M
 32000  -37.1 -34.8   295   56   29   9.0   4.9   46.0 114.9     9.0      M    M
 30000  -32.0 -25.6   290   50   26   8.5   4.7   45.1 113.2     8.5      M    M
 29000  -29.4 -20.9   295   50   26   8.4   4.6   44.6 112.2     8.2      M    M
 28000  -27.5 -17.5   295   50   26   4.5   2.5   43.3 110.0     7.3      M    M
 27000  -25.3 -13.5   295   41   21   9.1   5.0   42.3 108.2     6.6      M    M
 26000  -22.5  -8.5   295   33   17   9.4   5.2   42.1 107.9     6.5      M    M
 25000  -20.4  -4.7   295   24   12   5.9   3.2   41.1 106.0     5.8      M    M
 24000  -18.2  -0.8   285   29   15   7.7   4.2   40.3 104.5     5.2      M    M
 23000  -15.6   3.9   290   29   15   9.2   5.1   39.8 103.7     4.9      M    M
 22000  -12.8   9.0   300   29   15   8.5   4.6   39.7 103.4     4.8      M    M
 21000  -10.4  13.3   305   29   15   7.9   4.3   39.0 102.3     4.3      M    M
 20000   -8.1  17.4   300   29   15   7.9   4.3   38.4 101.1     3.8      M    M
 19500   -6.9  19.6   295   31   16   7.0   3.8   38.1 100.5     3.5      M    M
 19000   -6.0  21.2   295   31   16   7.0   3.9   37.5  99.4     3.0      M    M
 18500   -4.9  23.2   295   29   15   7.3   4.0   37.0  98.6     2.7      M    M
 18000   -3.8  25.2   300   27   14   7.3   4.0   36.6  97.8     2.3      M    M
 17500   -2.1  28.2   305   24   13   7.2   4.0   36.0  96.7     1.8      M    M
 17000   -1.0  30.2   305   23   12   5.9   3.3   35.6  96.1     1.5      M    M
 16500   -0.5  31.1   300   25   13   5.1   2.8   34.5  94.2     0.5      M    M
 16000    0.6  33.1   300   28   14   8.0   4.4   34.2  93.5     0.2      M    M
 15500    1.8  35.2   295   32   17   8.3   4.6   33.9  93.0    -0.1    862  4.4
 15000    2.8  37.0   295   35   18   5.5   3.0   33.4  92.2    -0.5    817  4.1
 14500    3.7  38.7   295   29   15   5.8   3.2   32.8  91.0    -1.2    776  3.9
 14000    4.6  40.3   300   22   12   5.9   3.2   32.1  89.8    -1.7    735  3.7
 13500    5.4  41.7   305   18    9   4.9   2.7   31.4  88.6    -2.4    697  3.5
 13000    6.0  42.8   315   14    7   5.4   3.0   30.6  87.1    -3.3    664  3.4
 12500    6.3  43.3   320    8    4  -1.5  -0.8   29.5  85.2    -4.5    639  3.2
 12000    6.4  43.5   340    2    1   7.8   4.3   28.2  82.7    -5.9    621  3.2
 11500    7.8  46.0   015    3    2   9.2   5.1   28.1  82.6    -6.0    565  2.9
 11000    9.2  48.6   025    5    2   9.3   5.1   28.0  82.4    -6.1    508  2.6
 10500   10.6  51.1   035    6    3   9.3   5.1   28.0  82.4    -6.1    451  2.3
 10250   11.3  52.3   030    8    4   9.1   5.0   27.9  82.3    -6.2    423  2.2
 10000   11.9  53.4   025   10    5   9.0   5.0   27.9  82.2    -6.3    396  2.0
  9750   12.6  54.7   025   10    5   9.1   5.0   27.8  82.1    -6.3    368  1.9
  9500   13.3  55.9   020   11    6   9.1   5.0   27.8  82.0    -6.4    340  1.7
  9250   14.0  57.2   020   11    6   9.1   5.0   27.7  81.9    -6.5    313  1.6
  9000   14.6  58.3   020   12    6   9.1   5.0   27.7  81.8    -6.5    285  1.4
  8750   15.3  59.5   030   13    7   8.1   4.4   27.6  81.7    -6.6    258  1.3
  8500   15.9  60.6   035   14    7   7.3   4.0   27.4  81.4    -6.8    234  1.2
  8250   16.4  61.5   040   16    8   7.6   4.2   27.2  81.0    -7.0    210  1.1
  8000   17.0  62.6   045   18    9   7.3   4.0   27.1  80.7    -7.2    186  0.9
  7750   17.5  63.5   045   17    9   8.1   4.4   26.9  80.4    -7.4    162  0.8
  7500   18.1  64.6   050   15    8   5.3   2.9   26.7  80.1    -7.6    138  0.7
  7250   18.3  64.9   050   14    7   1.5   0.8   26.2  79.2    -8.1    124  0.6
  7000   18.5  65.3   055   12    6   6.7   3.7   25.7  78.3    -8.6    109  0.6
  6750   19.3  66.7   055   11    6  10.6   5.8   25.7  78.3    -8.7     80  0.4
  6500   20.0  68.0   055   10    5   9.6   5.3   25.7  78.3    -8.7     51  0.3
  6250   20.7  69.3   055    9    5   9.8   5.4   25.7  78.3    -8.7     22  0.1
  6000   21.4  70.5   055    8    4   9.9   5.5   25.7  78.3    -8.7      M    M
  5750   22.1  71.8   055    7    3   9.2   5.1   25.7  78.3    -8.8      M    M
  5500   22.7  72.9   050    5    3   4.6   2.5   25.5  78.0    -9.0      M    M
  5250   22.9  73.2   045    3    2   3.3   1.8   25.0  77.0    -9.5      M    M
  5000   23.1  73.6   035    2    1   0.1   0.0   24.5  76.1   -10.1      M    M

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

           06/23/2017 at 0900 MDT          |       06/23/2017 at 1200 MDT
                                           |
K index... -0.2  LI... +4.2                | K index... -6.3  LI... +2.7
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -62.6 -80.7  305  42 22   1.4   0.7 | -62.9 -81.2  305  41 21   1.4   0.8
 45000 -59.5 -75.1  305  57 29   3.5   1.9 | -59.6 -75.3  300  53 27   3.9   2.1
 40000 -53.9 -65.0  305  59 31   6.7   3.7 | -53.4 -64.1  295  60 31   6.2   3.4
 38000 -49.9 -57.8  305  60 31   6.6   3.6 | -49.7 -57.5  300  57 29   6.2   3.4
 36000 -46.0 -50.8  305  61 32   6.6   3.6 | -46.0 -50.8  300  54 28   6.1   3.3
 34000 -41.2 -42.2  305  60 31   8.2   4.5 | -41.2 -42.2  305  54 28   8.4   4.6
 32000 -35.7 -32.3  305  58 30   8.3   4.5 | -35.5 -31.9  305  54 28   8.4   4.6
 30000 -31.4 -24.5  305  53 27   7.1   3.9 | -30.8 -23.4  305  50 26   7.8   4.3
 29000 -29.2 -20.6  305  49 25   7.1   3.9 | -28.4 -19.1  305  48 25   7.8   4.3
 28000 -27.1 -16.8  300  46 24   6.9   3.8 | -26.1 -15.0  305  46 24   6.7   3.7
 27000 -25.0 -13.0  300  43 22   6.9   3.8 | -24.3 -11.7  305  43 22   6.3   3.4
 26000 -23.0  -9.4  300  40 21   6.9   3.8 | -22.4  -8.3  305  40 21   6.3   3.4
 25000 -21.0  -5.8  300  37 19   6.9   3.8 | -20.5  -4.9  305  37 19   6.3   3.5
 24000 -18.7  -1.7  300  35 18   7.6   4.2 | -18.4  -1.1  305  35 18   7.1   3.9
 23000 -16.4   2.5  300  33 17   7.6   4.2 | -16.3   2.7  305  34 17   7.1   3.9
 22000 -14.2   6.4  300  31 16   7.7   4.2 | -14.2   6.4  300  32 17   7.3   4.0
 21000 -11.7  10.9  300  31 16   8.1   4.4 | -11.9  10.6  300  30 16   7.8   4.3
 20000  -9.3  15.3  300  30 15   8.1   4.4 |  -9.6  14.7  300  28 14   7.8   4.3
 19500  -8.1  17.4  300  30 15   8.1   4.4 |  -8.4  16.9  300  27 14   7.8   4.3
 19000  -6.9  19.6  300  29 15   7.8   4.3 |  -7.2  19.0  300  26 13   7.8   4.3
 18500  -5.7  21.7  300  29 15   7.8   4.3 |  -6.0  21.2  305  25 13   7.8   4.3
 18000  -4.6  23.7  300  28 14   7.7   4.2 |  -4.8  23.4  305  23 12   7.8   4.3
 17500  -3.4  25.9  305  27 14   7.6   4.2 |  -3.7  25.3  305  21 11   7.7   4.2
 17000  -2.3  27.9  305  26 14   7.7   4.2 |  -2.5  27.5  305  20 10   7.7   4.2
 16500  -1.2  29.8  305  25 13   6.8   3.7 |  -1.4  29.5  310  18  9   7.3   4.0
 16000  -0.2  31.6  305  24 12   6.8   3.7 |  -0.3  31.5  310  17  9   7.3   4.0
 15500   0.8  33.4  310  23 12   6.8   3.7 |   0.8  33.4  315  15  8   7.2   4.0
 15000   2.3  36.1  310  21 11   6.8   3.7 |   2.4  36.3  315  14  7   7.1   3.9
 14500   3.3  37.9  310  19 10   6.2   3.4 |   3.5  38.3  315  13  7   7.2   3.9
 14000   4.2  39.6  315  18  9   6.0   3.3 |   4.5  40.1  320  13  7   7.2   3.9
 13500   5.1  41.2  315  16  8   5.8   3.2 |   5.6  42.1  320  12  6   6.4   3.5
 13000   5.9  42.6  320  14  7   5.7   3.1 |   6.5  43.7  320  11  6   5.8   3.2
 12500   6.7  44.1  320  12  6   5.5   3.0 |   7.3  45.1  325  10  5   5.4   3.0
 12000   7.3  45.1  320   9  5   5.2   2.9 |   8.0  46.4  330   7  4   5.1   2.8
 11500   8.0  46.4  325   6  3   6.1   3.3 |   8.6  47.5  335   5  3   5.9   3.2
 11000   9.0  48.2  330   5  3   7.6   4.2 |   9.5  49.1  335   4  2   6.7   3.7
 10500  10.1  50.2  345   4  2   4.0   2.2 |  10.5  50.9  335   4  2   4.0   2.2
 10250  10.3  50.5  360   4  2   5.6   3.0 |  10.7  51.3  335   4  2   5.9   3.2
 10000  11.0  51.8  015   5  3  11.3   6.2 |  11.4  52.5  340   4  2  10.9   6.0
  9750  11.8  53.2  025   6  3  10.4   5.7 |  12.1  53.8  340   4  2  10.2   5.6
  9500  12.5  54.5  035   7  4   8.2   4.5 |  12.8  55.0  340   5  2   8.2   4.5
  9250  13.0  55.4  035   8  4   5.8   3.2 |  13.3  55.9  340   5  2   7.1   3.9
  9000  13.5  56.3  035   9  5   8.1   4.4 |  13.9  57.0  340   5  2   9.8   5.4
  8750  14.2  57.6  040  10  5   9.6   5.2 |  14.6  58.3  340   5  2  10.3   5.7
  8500  14.8  58.6  040  11  6   7.3   4.0 |  15.4  59.7  340   5  2   9.6   5.3
  8250  15.2  59.4  040  11  6   5.5   3.0 |  16.0  60.8  340   5  2   8.9   4.9
  8000  15.7  60.3  040  11  6   5.1   2.8 |  16.7  62.1  340   5  2   9.5   5.2
  7750  16.0  60.8  040  11  6   4.0   2.2 |  17.4  63.3  335   5  2   9.9   5.4
  7500  16.2  61.2  040  11  6   1.6   0.9 |  18.1  64.6  335   5  2   9.9   5.4
  7250  16.2  61.2  040  10  5   0.1   0.0 |  18.9  66.0  335   5  2  10.0   5.5
  7000  16.2  61.2  040  10  5  -0.6  -0.3 |  19.6  67.3  335   5  2  10.0   5.5
  6750  16.1  61.0  040   9  5   1.4   0.8 |  20.4  68.7  330   5  2  10.7   5.9
  6500  16.4  61.5  035   8  4   6.2   3.4 |  21.2  70.2  330   5  2  11.3   6.2
  6250  16.9  62.4  035   7  4   6.8   3.8 |  22.1  71.8  330   4  2  12.0   6.6
  6000  17.4  63.3  030   6  3   7.0   3.9 |  22.9  73.2  325   4  2  10.0   5.5
  5750  18.1  64.6  025   6  3  10.5   5.7 |  23.7  74.7  325   4  2  13.3   7.3
  5500  19.0  66.2  025   6  3  13.0   7.1 |  25.0  77.0  325   5  2  18.7  10.3
  5250  19.9  67.8  025   6  3  11.1   6.1 |  26.2  79.2  330   5  2  14.4   7.9
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           06/23/2017 at 1500 MDT          |       06/23/2017 at 1800 MDT
                                           |
K index... -14.4  LI... +2.5               | K index... -3.1  LI... +2.1
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -62.5 -80.5  310  43 22   1.0   0.5 | -62.5 -80.5  310  42 22   1.2   0.7
 45000 -59.8 -75.6  300  56 29   3.8   2.1 | -59.5 -75.1  305  55 28   4.0   2.2
 40000 -53.7 -64.7  295  62 32   6.3   3.4 | -52.8 -63.0  300  56 29   5.9   3.3
 38000 -49.9 -57.8  295  57 29   6.3   3.5 | -49.2 -56.6  300  54 28   6.0   3.3
 36000 -46.1 -51.0  300  53 27   6.2   3.4 | -45.7 -50.3  300  52 27   5.8   3.2
 34000 -41.4 -42.5  300  52 27   8.2   4.5 | -41.1 -42.0  300  50 26   7.9   4.3
 32000 -35.8 -32.4  300  51 26   8.2   4.5 | -36.3 -33.3  300  49 25   7.8   4.3
 30000 -30.9 -23.6  300  48 25   8.2   4.5 | -31.3 -24.3  305  46 24   8.5   4.7
 29000 -28.4 -19.1  305  46 24   8.2   4.5 | -28.8 -19.8  305  44 23   8.5   4.7
 28000 -26.0 -14.8  305  44 23   6.9   3.8 | -26.2 -15.2  305  42 22   8.0   4.4
 27000 -24.0 -11.2  305  41 21   6.5   3.6 | -24.0 -11.2  305  40 21   7.4   4.0
 26000 -22.1  -7.8  305  38 19   6.5   3.6 | -21.3  -6.3  305  37 19   7.4   4.0
 25000 -20.2  -4.4  300  35 18   6.5   3.6 | -19.1  -2.4  305  35 18   6.9   3.8
 24000 -18.2  -0.8  300  33 17   6.7   3.7 | -17.2   1.0  300  34 17   6.2   3.4
 23000 -16.1   3.0  300  31 16   6.7   3.7 | -15.3   4.5  300  32 17   6.2   3.4
 22000 -14.1   6.6  300  29 15   7.0   3.8 | -13.5   7.7  300  31 16   6.7   3.7
 21000 -11.9  10.6  300  27 14   7.5   4.1 | -11.3  11.7  300  29 15   7.3   4.0
 20000  -9.7  14.5  300  25 13   7.5   4.1 |  -9.1  15.6  305  27 14   7.3   4.0
 19500  -8.5  16.7  300  24 12   7.5   4.1 |  -8.1  17.4  305  26 13   7.3   4.0
 19000  -7.4  18.7  300  22 12   7.9   4.3 |  -7.0  19.4  305  25 13   7.3   4.0
 18500  -6.2  20.8  300  21 11   7.9   4.3 |  -5.9  21.4  305  24 12   7.3   4.0
 18000  -5.0  23.0  300  20 10   7.8   4.3 |  -4.8  23.4  305  23 12   7.5   4.1
 17500  -3.8  25.2  305  19 10   7.7   4.2 |  -3.7  25.3  305  22 11   7.6   4.2
 17000  -2.7  27.1  305  17  9   7.7   4.2 |  -2.5  27.5  310  21 11   7.6   4.2
 16500  -1.5  29.3  305  16  8   7.8   4.3 |  -1.3  29.7  310  20 10   7.9   4.4
 16000  -0.3  31.5  305  15  8   7.8   4.3 |  -0.2  31.6  310  19 10   7.9   4.3
 15500   1.4  34.5  310  13  7   8.2   4.5 |   1.0  33.8  310  18  9   8.0   4.4
 15000   2.7  36.9  310  12  6   8.2   4.5 |   2.2  36.0  315  16  8   8.0   4.4
 14500   3.9  39.0  310  11  6   7.7   4.2 |   3.4  38.1  320  14  7   8.1   4.4
 14000   5.0  41.0  310  11  5   7.7   4.2 |   4.5  40.1  320  13  7   8.0   4.4
 13500   6.2  43.2  310  10  5   7.4   4.1 |   5.7  42.3  325  12  6   8.1   4.5
 13000   7.2  45.0  315   9  4   7.3   4.0 |   7.5  45.5  335  11  6   8.6   4.7
 12500   8.3  46.9  320   8  4   7.3   4.0 |   8.8  47.8  340  10  5   8.3   4.6
 12000   9.3  48.7  325   7  4   7.4   4.0 |   9.9  49.8  340  10  5   8.2   4.5
 11500  10.4  50.7  330   7  4   7.4   4.1 |  11.1  52.0  345   9  5   8.4   4.6
 11000  11.4  52.5  330   7  3   7.2   3.9 |  12.3  54.1  345   8  4   8.4   4.6
 10500  12.4  54.3  335   7  3   4.4   2.4 |  13.5  56.3  345   8  4   5.4   3.0
 10250  12.6  54.7  330   7  3   5.7   3.1 |  13.8  56.8  345   8  4   6.4   3.5
 10000  13.3  55.9  330   7  3  10.4   5.7 |  14.5  58.1  340   7  4  11.1   6.1
  9750  14.0  57.2  330   6  3   9.5   5.2 |  15.3  59.5  340   7  4  10.5   5.8
  9500  14.6  58.3  330   6  3   8.7   4.8 |  16.0  60.8  340   7  4   8.2   4.5
  9250  15.2  59.4  330   6  3   8.4   4.6 |  16.5  61.7  335   7  3   7.4   4.1
  9000  15.8  60.4  325   6  3  10.0   5.5 |  17.2  63.0  335   6  3  10.0   5.5
  8750  16.5  61.7  325   6  3  10.0   5.5 |  17.9  64.2  330   6  3   9.4   5.2
  8500  17.2  63.0  325   6  3  10.1   5.6 |  18.6  65.5  330   6  3   9.9   5.5
  8250  18.0  64.4  325   6  3  10.2   5.6 |  19.3  66.7  325   6  3  10.2   5.6
  8000  18.7  65.7  320   6  3   9.5   5.2 |  20.1  68.2  325   6  3   9.7   5.3
  7750  19.4  66.9  320   6  3   9.2   5.0 |  20.8  69.4  320   6  3   9.5   5.2
  7500  20.2  68.4  320   6  3  10.3   5.6 |  21.5  70.7  320   6  3   9.9   5.4
  7250  21.0  69.8  315   6  3  11.3   6.2 |  22.2  72.0  320   6  3  10.3   5.6
  7000  21.8  71.2  315   6  3   9.9   5.4 |  23.0  73.4  315   6  3   9.7   5.3
  6750  22.5  72.5  315   6  3   9.6   5.3 |  23.7  74.7  315   6  3   9.8   5.4
  6500  23.3  73.9  315   6  3  11.2   6.2 |  24.5  76.1  315   5  3  10.7   5.8
  6250  24.1  75.4  310   6  3  12.3   6.7 |  25.3  77.5  310   5  3  11.4   6.2
  6000  25.0  77.0  310   6  3   9.9   5.4 |  26.1  79.0  310   5  3   9.6   5.3
  5750  25.8  78.4  310   6  3  13.4   7.3 |  26.8  80.2  305   5  3  10.3   5.6
  5500  27.1  80.8  310   6  3  19.2  10.6 |  27.7  81.9  310   5  3  13.1   7.2
  5250  28.4  83.1  310   6  3  14.6   8.0 |  28.6  83.5  315   5  3  11.1   6.1
  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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