Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 301235
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0635 MDT Saturday, May 30, 2015

This forecast is for Saturday, May 30, 2015:

If the trigger temperature of 70.3 F/21.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1054 ft/min (5.4 m/s)
   Maximum height of thermals.................. 16966 ft MSL (12127 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 1130 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................. 13686 ft MSL (8846 ft AGL)
Thermal soaring outlook for Sunday 05/31....... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:51:10 / 20:32:00 MDT
Total possible sunshine........... 14 hr 40 min 50 sec (880 min 50 sec)
Altitude of sun at 13:11:47 MDT... 72.67 degrees

Upper air data from rawinsonde observation taken on 05/30/2015 at 0600 MDT

Freezing level.................. 12668 ft MSL (7829 ft AGL)
Convective condensation level... 15261 ft MSL (10422 ft AGL)
Lifted condensation level....... 16055 ft MSL (11216 ft AGL)
Lifted index.................... -0.8
K index......................... +15.2

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  -60.4 -76.7   300   19   10  -8.0  -4.4   98.5 209.3    40.5      M    M
 45000  -61.0 -77.8   305   29   15   3.0   1.7   72.8 163.1    27.6      M    M
 40000  -62.3 -80.1   340   49   25   7.6   4.2   46.6 116.0    12.4      M    M
 38000  -57.2 -71.0   340   48   25   8.5   4.7   45.4 113.8    12.0      M    M
 36000  -52.1 -61.8   335   44   23   8.5   4.7   44.2 111.6    11.5      M    M
 34000  -47.1 -52.8   335   39   20   8.5   4.7   43.1 109.6    11.0      M    M
 32000  -42.0 -43.6   330   33   17   7.7   4.2   42.2 108.0    10.6      M    M
 30000  -36.8 -34.2   325   34   17   9.2   5.0   40.4 104.7     9.5      M    M
 29000  -34.0 -29.2   320   33   17   9.3   5.1   40.2 104.4     9.5      M    M
 28000  -32.1 -25.8   320   32   17   3.2   1.8   38.9 102.0     8.6      M    M
 27000  -29.8 -21.6   315   32   16   8.9   4.9   38.0 100.5     8.0      M    M
 26000  -27.1 -16.8   315   31   16   8.9   4.9   37.7  99.8     7.8      M    M
 25000  -24.5 -12.1   310   31   16   7.4   4.1   37.4  99.4     7.7      M    M
 24000  -22.8  -9.0   310   28   15   5.1   2.8   35.8  96.5     6.5      M    M
 23000  -20.9  -5.6   310   25   13   7.5   4.1   34.5  94.1     5.5      M    M
 22000  -18.7  -1.7   310   22   11   7.6   4.2   33.7  92.6     4.9      M    M
 21000  -16.4   2.5   315   19   10   7.6   4.2   33.0  91.3     4.3      M    M
 20000  -14.1   6.6   315   16    8   7.6   4.2   32.3  90.2     3.9      M    M
 19500  -13.0   8.6   320   15    8   7.6   4.2   31.9  89.5     3.5      M    M
 19000  -11.9  10.6   325   14    7   8.7   4.8   31.5  88.8     3.2      M    M
 18500  -10.8  12.6   320   14    7   4.2   2.3   31.0  87.9     2.8      M    M
 18000  -10.2  13.6   320   14    7   4.5   2.4   30.1  86.2     2.0      M    M
 17500   -9.5  14.9   315   13    7   4.2   2.3   29.2  84.6     1.2      M    M
 17000   -9.0  15.8   315   13    7   4.4   2.4   28.2  82.8     0.2      M    M
 16500   -8.2  17.2   310   13    7   7.5   4.1   27.6  81.7    -0.4   1024  5.2
 16000   -6.6  20.1   305   13    7   7.3   4.0   27.0  80.6    -1.0    954  4.8
 15500   -5.5  22.1   310   13    7   7.4   4.1   26.6  79.9    -1.4    907  4.6
 15000   -4.6  23.7   320   13    7   3.9   2.2   26.0  78.9    -1.9    865  4.4
 14500   -3.9  25.0   325   13    7   8.2   4.5   25.3  77.5    -2.7    829  4.2
 14000   -2.6  27.3   330   13    7   8.8   4.8   25.1  77.1    -2.9    777  3.9
 13500   -1.7  28.9   330   14    7   3.7   2.1   24.6  76.3    -3.4    734  3.7
 13000   -0.8  30.6   330   14    7  10.1   5.5   24.1  75.4    -4.0    692  3.5
 12500    0.6  33.1   330   15    7   9.5   5.2   24.1  75.3    -4.1    635  3.2
 12000    2.0  35.6   330   15    8   9.4   5.2   24.0  75.3    -4.1    578  2.9
 11500    3.4  38.1   335   12    6   9.4   5.2   24.0  75.2    -4.2    520  2.6
 11000    4.7  40.5   340    8    4   6.7   3.7   23.7  74.6    -4.5    469  2.4
 10500    5.8  42.4   350    6    3   7.3   4.0   23.3  73.9    -4.8    422  2.1
 10250    6.4  43.5   355    5    2   8.3   4.5   23.1  73.6    -5.0    396  2.0
 10000    7.0  44.6   360    4    2   8.9   4.9   23.0  73.4    -5.1    369  1.9
  9750    7.7  45.9   360    4    2   7.4   4.1   22.9  73.3    -5.1    343  1.7
  9500    8.0  46.4   005    3    2   5.2   2.8   22.6  72.7    -5.5    324  1.6
  9250    8.3  46.9   010    3    1   6.6   3.6   22.3  72.1    -6.0    307  1.6
  9000    8.9  48.0   020    2    1   8.2   4.5   22.1  71.8    -6.1    283  1.4
  8750    9.5  49.1   065    3    1   8.2   4.5   22.0  71.6    -6.3    258  1.3
  8500   10.1  50.2   085    4    2   8.1   4.5   21.9  71.4    -6.4    232  1.2
  8250   10.7  51.3   095    6    3   5.0   2.7   21.7  71.0    -6.6    209  1.1
  8000   10.9  51.6   100    8    4   2.8   1.5   21.2  70.1    -7.1    194  1.0
  7750   11.1  52.0   105    8    4   3.4   1.9   20.7  69.2    -7.7    180  0.9
  7500   11.3  52.3   110    9    5   3.2   1.8   20.2  68.3    -8.2    166  0.8
  7250   11.6  52.9   110    9    5   3.3   1.8   19.7  67.4    -8.7    152  0.8
  7000   11.8  53.2   115   10    5   3.3   1.8   19.2  66.5    -9.2    137  0.7
  6750   12.0  53.6   110   10    5   3.1   1.7   18.7  65.6    -9.7    123  0.6
  6500   12.3  54.1   105   10    5   3.7   2.0   18.2  64.7   -10.3    109  0.6
  6250   12.6  54.7   100   11    5   6.4   3.5   17.8  64.1   -10.7     91  0.5
  6000   13.2  55.8   095   11    6   7.8   4.3   17.7  63.8   -10.9     67  0.3
  5750   13.7  56.7   095   10    5   7.3   4.0   17.5  63.5   -11.1     44  0.2
  5500   14.2  57.6   090   10    5   8.2   4.5   17.3  63.2   -11.3     20  0.1
  5250   14.8  58.6   090    9    5   5.1   2.8   17.1  62.9   -11.5      M    M
  5000   14.6  58.3   085    8    4 -11.0  -6.1   16.3  61.3   -12.4      M    M

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

           05/30/2015 at 0900 MDT          |       05/30/2015 at 1200 MDT
                                           |
K index... +4.8  LI... +275.8              | K index... +17.1  LI... +273.8
CAPE... 0.0  CIN... M                      | CAPE... +0.8  CIN... -13.3
                                           |
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 -62.0 -79.6  310  19 10   0.4   0.2 | -63.2 -81.8  310  22 11  -0.0  -0.0
 45000 -61.5 -78.7  325  35 18   0.1   0.0 | -63.0 -81.4  330  33 17   1.2   0.6
 40000 -61.4 -78.5  335  46 24   4.2   2.3 | -61.2 -78.2  335  42 22   4.8   2.6
 38000 -56.5 -69.7  335  44 23   8.1   4.4 | -56.3 -69.3  335  42 22   8.2   4.5
 36000 -51.6 -60.9  335  41 21   8.1   4.4 | -51.4 -60.5  335  43 22   8.2   4.5
 34000 -46.7 -52.1  330  38 20   8.4   4.6 | -46.6 -51.9  330  41 21   8.0   4.4
 32000 -41.6 -42.9  330  35 18   8.4   4.6 | -41.8 -43.2  330  37 19   8.0   4.4
 30000 -36.6 -33.9  325  33 17   8.3   4.5 | -35.9 -32.6  325  33 17   9.3   5.1
 29000 -34.1 -29.4  325  31 16   8.3   4.5 | -33.1 -27.6  325  31 16   9.3   5.1
 28000 -31.6 -24.9  325  30 15   8.3   4.6 | -30.3 -22.5  325  29 15   9.1   5.0
 27000 -29.3 -20.7  325  29 15   7.6   4.2 | -28.0 -18.4  320  27 14   7.2   3.9
 26000 -27.0 -16.6  325  27 14   7.6   4.2 | -25.9 -14.6  320  25 13   7.2   3.9
 25000 -24.7 -12.5  325  25 13   7.6   4.2 | -23.7 -10.7  320  23 12   7.2   3.9
 24000 -22.5  -8.5  320  23 12   6.8   3.7 | -21.6  -6.9  315  21 11   7.1   3.9
 23000 -20.4  -4.7  315  21 11   6.8   3.7 | -19.4  -2.9  315  20 10   7.2   3.9
 22000 -17.9  -0.2  310  18  9   6.8   3.7 | -17.3   0.9  315  18  9   7.3   4.0
 21000 -15.9   3.4  305  16  8   6.6   3.6 | -15.4   4.3  310  17  9   5.8   3.2
 20000 -13.9   7.0  300  14  7   6.6   3.6 | -13.7   7.3  305  16  8   5.8   3.2
 19500 -12.9   8.8  295  13  7   6.6   3.6 | -12.8   9.0  305  16  8   5.8   3.2
 19000 -12.0  10.4  290  12  6   5.7   3.1 | -12.0  10.4  300  16  8   5.6   3.1
 18500 -11.1  12.0  285  12  6   5.6   3.1 | -11.2  11.8  300  16  8   5.6   3.1
 18000 -10.3  13.5  285  11  6   5.7   3.1 | -10.0  14.0  300  16  8   5.4   3.0
 17500  -9.4  15.1  285  11  6   5.8   3.2 |  -9.2  15.4  300  16  8   5.3   2.9
 17000  -8.6  16.5  280  11  6   5.9   3.2 |  -8.5  16.7  300  16  8   5.4   3.0
 16500  -7.7  18.1  280  11  5   5.9   3.2 |  -7.6  18.3  300  17  8   6.6   3.6
 16000  -6.9  19.6  285  10  5   5.9   3.3 |  -6.7  19.9  300  16  8   6.4   3.5
 15500  -6.0  21.2  285  10  5   6.6   3.6 |  -5.7  21.7  300  16  8   8.1   4.4
 15000  -5.0  23.0  290  10  5   7.0   3.8 |  -4.5  23.9  300  15  8   8.2   4.5
 14500  -4.0  24.8  290  10  5   7.7   4.2 |  -3.3  26.1  295  14  7   8.8   4.8
 14000  -2.8  27.0  290  10  5   8.7   4.8 |  -1.9  28.6  290  14  7   9.1   5.0
 13500  -1.6  29.1  290  10  5   9.0   4.9 |  -0.6  30.9  285  13  7   8.8   4.8
 13000  -0.3  31.5  285  10  5   9.4   5.1 |   0.6  33.1  280  13  7   8.4   4.6
 12500   1.0  33.8  285  10  5   9.4   5.1 |   1.8  35.2  280  12  6   8.5   4.6
 12000   2.4  36.3  280   9  5   9.1   5.0 |   3.0  37.4  275  12  6   8.5   4.7
 11500   3.8  38.8  275   8  4   9.0   4.9 |   4.2  39.6  270  11  6   8.7   4.8
 11000   5.1  41.2  265   7  4   7.8   4.3 |   5.5  41.9  265  11  6   9.0   4.9
 10500   6.3  43.3  255   6  3   7.5   4.1 |   6.9  44.4  260  10  5   6.0   3.3
 10250   6.8  44.2  250   5  3   6.2   3.4 |   7.2  45.0  260  10  5   4.7   2.6
 10000   7.3  45.1  245   5  2   6.8   3.7 |   7.8  46.0  260  10  5  10.4   5.7
  9750   7.8  46.0  240   4  2   7.9   4.3 |   8.6  47.5  255   9  5  12.3   6.7
  9500   8.4  47.1  230   4  2   7.3   4.0 |   9.5  49.1  255   8  4   9.6   5.3
  9250   8.9  48.0  220   4  2   6.6   3.6 |  10.0  50.0  255   8  4   5.9   3.2
  9000   9.3  48.7  210   4  2   6.7   3.7 |  10.5  50.9  250   7  4   7.4   4.1
  8750   9.8  49.6  195   4  2   7.2   3.9 |  11.1  52.0  245   6  3   9.6   5.3
  8500  10.3  50.5  185   4  2   6.8   3.7 |  11.8  53.2  240   5  3   7.6   4.2
  8250  10.8  51.4  180   5  3   6.3   3.5 |  12.3  54.1  230   4  2   6.1   3.3
  8000  11.2  52.2  175   6  3   6.3   3.5 |  12.7  54.9  215   3  2   6.5   3.6
  7750  11.7  53.1  170   7  4   6.5   3.6 |  13.2  55.8  200   3  2   6.8   3.8
  7500  12.1  53.8  170   8  4   5.1   2.8 |  13.8  56.8  190   3  2   8.8   4.8
  7250  12.4  54.3  165   8  4   4.0   2.2 |  14.5  58.1  190   3  2   9.9   5.5
  7000  12.7  54.9  160   9  4   4.4   2.4 |  15.2  59.4  190   3  2   9.6   5.3
  6750  13.0  55.4  160   9  5   3.5   1.9 |  15.9  60.6  185   4  2  10.2   5.6
  6500  13.2  55.8  155   8  4   2.7   1.5 |  16.7  62.1  185   4  2  10.6   5.8
  6250  13.4  56.1  155   7  4   2.5   1.4 |  17.4  63.3  185   3  2  10.5   5.8
  6000  13.6  56.5  150   6  3   3.5   1.9 |  18.2  64.8  185   3  2  10.8   5.9
  5750  14.0  57.2  145   6  3  11.1   6.1 |  19.2  66.6  185   3  2  17.5   9.6
  5500  15.2  59.4  140   5  3  20.7  11.3 |  20.9  69.6  190   3  2  27.5  15.1
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/30/2015 at 1500 MDT          |       05/30/2015 at 1800 MDT
                                           |
K index... +14.8  LI... +272.9             | K index... +16.4  LI... +273.3
CAPE... +19.5  CIN... -42.6                | CAPE... 0.0  CIN... M
                                           |
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 -64.1 -83.4  310  26 13  -1.0  -0.6 | -64.2 -83.6  315  23 12  -1.8  -1.0
 45000 -64.9 -84.8  320  37 19   2.4   1.3 | -65.8 -86.4  325  35 18   2.8   1.5
 40000 -61.0 -77.8  320  36 19   6.7   3.7 | -61.4 -78.5  325  44 22   7.7   4.2
 38000 -56.0 -68.8  330  36 19   8.3   4.5 | -56.1 -69.0  325  41 21   8.9   4.9
 36000 -51.0 -59.8  335  37 19   8.3   4.5 | -50.7 -59.3  330  38 20   8.9   4.9
 34000 -46.1 -51.0  335  37 19   8.3   4.5 | -45.6 -50.1  330  35 18   8.5   4.7
 32000 -41.1 -42.0  325  36 19   8.3   4.5 | -40.5 -40.9  330  32 16   8.5   4.7
 30000 -35.9 -32.6  325  34 18   9.0   4.9 | -35.5 -31.9  330  30 15   8.2   4.5
 29000 -32.5 -26.5  325  32 17   9.0   4.9 | -32.4 -26.3  330  29 15   8.2   4.5
 28000 -29.8 -21.6  330  31 16   8.9   4.9 | -30.0 -22.0  325  28 15   8.4   4.6
 27000 -27.2 -17.0  330  30 15   8.7   4.8 | -27.4 -17.3  325  26 13   8.6   4.7
 26000 -24.7 -12.5  330  28 14   8.7   4.8 | -24.8 -12.6  330  24 12   8.6   4.7
 25000 -22.1  -7.8  330  27 14   9.0   4.9 | -22.3  -8.1  330  22 11   8.7   4.8
 24000 -20.0  -4.0  325  25 13   6.2   3.4 | -20.0  -4.0  330  21 11   7.5   4.1
 23000 -18.2  -0.8  320  23 12   6.2   3.4 | -17.7   0.1  325  21 11   7.5   4.1
 22000 -16.3   2.7  310  22 11   6.2   3.4 | -15.5   4.1  325  22 11   7.5   4.1
 21000 -14.6   5.7  305  21 11   5.5   3.0 | -13.8   7.2  320  21 11   5.5   3.0
 20000 -13.0   8.6  305  19 10   5.5   3.0 | -12.2  10.0  315  21 11   5.6   3.1
 19500 -12.2  10.0  305  19 10   5.5   3.0 | -11.4  11.5  315  20 10   5.5   3.0
 19000 -11.4  11.5  305  18  9   5.6   3.1 | -10.5  13.1  315  20 10   6.3   3.5
 18500 -10.5  13.1  305  18  9   5.7   3.1 |  -9.6  14.7  310  18  9   6.5   3.5
 18000  -9.7  14.5  305  18  9   6.0   3.3 |  -8.6  16.5  310  17  9   6.5   3.6
 17500  -8.7  16.3  305  17  9   7.7   4.2 |  -7.6  18.3  305  15  8   6.9   3.8
 17000  -7.5  18.5  305  17  9   7.6   4.2 |  -6.6  20.1  300  14  7   6.8   3.7
 16500  -6.4  20.5  305  16  8   7.6   4.2 |  -5.5  22.1  295  13  7   7.7   4.2
 16000  -5.3  22.5  305  15  8   7.6   4.2 |  -4.4  24.1  290  12  6   7.7   4.2
 15500  -4.2  24.4  305  15  8   7.8   4.3 |  -3.2  26.2  285  11  6   7.9   4.4
 15000  -3.0  26.6  305  15  7   7.9   4.3 |  -2.0  28.4  280  11  6   8.1   4.5
 14500  -1.9  28.6  305  14  7   8.0   4.4 |  -0.8  30.6  275  11  6   8.2   4.5
 14000  -0.1  31.8  300  14  7   8.4   4.6 |   1.0  33.8  270  12  6   8.4   4.6
 13500   1.2  34.2  295  14  7   8.4   4.6 |   2.2  36.0  270  12  6   8.5   4.7
 13000   2.4  36.3  295  13  7   8.4   4.6 |   3.5  38.3  265  12  6   8.5   4.7
 12500   3.6  38.5  290  12  6   8.5   4.7 |   4.7  40.5  265  12  6   8.8   4.8
 12000   4.9  40.8  285  12  6   8.6   4.7 |   6.1  43.0  265  12  6   9.1   5.0
 11500   6.2  43.2  280  11  6   8.7   4.8 |   7.4  45.3  265  12  6   8.9   4.9
 11000   7.5  45.5  275  11  6   8.6   4.7 |   8.7  47.7  265  12  6   8.4   4.6
 10500   8.8  47.8  270  11  6   5.2   2.8 |  10.0  50.0  265  11  6   5.2   2.8
 10250   9.0  48.2  270  11  6   6.0   3.3 |  10.2  50.4  265  11  6   5.9   3.2
 10000   9.8  49.6  270  11  6  11.1   6.1 |  10.9  51.6  265  11  6  10.7   5.9
  9750  10.5  50.9  270  11  5  10.4   5.7 |  11.7  53.1  265  11  5   9.8   5.4
  9500  11.2  52.2  270  10  5   8.0   4.4 |  12.4  54.3  270  10  5   8.5   4.6
  9250  11.6  52.9  270   9  5   5.9   3.2 |  12.9  55.2  270  10  5   7.2   3.9
  9000  12.1  53.8  270   8  4   8.1   4.4 |  13.5  56.3  270   9  5   8.7   4.8
  8750  12.7  54.9  265   7  4   8.4   4.6 |  14.2  57.6  270   9  4   9.2   5.1
  8500  13.3  55.9  265   7  3   7.9   4.3 |  14.8  58.6  270   8  4   7.6   4.1
  8250  13.8  56.8  265   6  3   7.4   4.0 |  15.3  59.5  265   6  3   6.0   3.3
  8000  14.4  57.9  265   6  3   8.7   4.8 |  15.7  60.3  265   5  3   6.8   3.7
  7750  15.1  59.2  265   5  3  10.1   5.5 |  16.2  61.2  255   4  2   7.4   4.1
  7500  15.8  60.4  260   5  3  10.1   5.6 |  16.8  62.2  250   3  2   8.9   4.9
  7250  16.6  61.9  260   5  3  10.6   5.8 |  17.5  63.5  245   3  2   9.7   5.3
  7000  17.4  63.3  260   5  3   9.8   5.4 |  18.2  64.8  245   3  2   9.8   5.4
  6750  18.1  64.6  260   5  3  10.0   5.5 |  18.9  66.0  245   3  2  10.4   5.7
  6500  18.9  66.0  260   5  3  11.1   6.1 |  19.6  67.3  240   3  2  10.4   5.7
  6250  19.7  67.5  260   5  3  11.0   6.0 |  20.4  68.7  240   3  2  10.6   5.8
  6000  20.5  68.9  255   5  3  10.7   5.9 |  21.2  70.2  240   3  2   9.9   5.4
  5750  21.3  70.3  260   5  2  12.8   7.0 |  21.9  71.4  240   3  2   9.7   5.3
  5500  22.4  72.3  260   5  2  15.0   8.2 |  22.7  72.9  240   3  2  10.4   5.7
  5250  23.4  74.1  260   5  2  13.3   7.3 |  23.4  74.1  240   3  2   9.8   5.4
  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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