Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 221232
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0632 MDT Tuesday, August 22, 2017

This forecast is for Tuesday, August 22, 2017:

If the trigger temperature of 82.3 F/27.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 579 ft/min (2.9 m/s)
   Maximum height of thermals.................. 14039 ft MSL (9200 ft AGL)

Forecast maximum temperature................... 89.0 F/32.1 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9558 ft MSL (4719 ft AGL)
Thermal soaring outlook for Wednesday 08/23.... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:34:01 / 20:00:22 MDT
Total possible sunshine........... 13 hr 26 min 20 sec (806 min 20 sec)
Altitude of sun at 13:16:49 MDT... 62.39 degrees

Upper air data from rawinsonde observation taken on 08/22/2017 at 0600 MDT

Freezing level.................. 15516 ft MSL (10677 ft AGL)
Convective condensation level... 16089 ft MSL (11250 ft AGL)
Lifted condensation level....... 16008 ft MSL (11169 ft AGL)
Lifted index.................... -0.5
K index......................... +21.9

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  -64.9 -84.8   265   22   11  -1.2  -0.7   86.5 187.6    31.7      M    M
 45000  -58.9 -74.0   235   38   20   5.3   2.9   70.9 159.7    24.5      M    M
 40000  -49.1 -56.4   240   43   22   6.5   3.5   63.4 146.1    21.1      M    M
 38000  -46.7 -52.1   240   35   18   3.6   2.0   58.2 136.8    18.2      M    M
 36000  -45.9 -50.6   260   19   10  -1.0  -0.6   51.0 123.9    13.6      M    M
 34000  -42.5 -44.5   220   15    8   8.8   4.8   47.5 117.6    11.4      M    M
 32000  -36.7 -34.1   220   10    5   8.4   4.6   46.6 115.8    11.0      M    M
 30000  -32.0 -25.6   215   11    6   8.1   4.4   45.2 113.3    10.2      M    M
 29000  -29.5 -21.1   215    8    4   8.1   4.4   44.5 112.1     9.8      M    M
 28000  -27.2 -17.0   215    6    3   8.0   4.4   43.7 110.7     9.3      M    M
 27000  -24.8 -12.6   215    4    2   7.9   4.4   43.1 109.6     8.9      M    M
 26000  -22.3  -8.1   220    1    1   9.7   5.3   42.5 108.6     8.6      M    M
 25000  -19.4  -2.9   030    1    1   7.0   3.9   42.5 108.5     8.6      M    M
 24000  -17.5   0.5   320    1    1   7.0   3.9   41.3 106.4     7.7      M    M
 23000  -15.2   4.6   330    1    1   7.9   4.3   40.5 104.9     7.2      M    M
 22000  -13.9   7.0   340    1    1   5.0   2.8   38.7 101.6     5.6      M    M
 21000  -12.4   9.7   345    2    1   5.7   3.1   37.1  98.8     4.3      M    M
 20000  -11.4  11.5   350    2    1   3.0   1.7   35.0  94.9     2.4      M    M
 19500  -10.5  13.1   035    2    1   6.1   3.3   34.3  93.8     1.9      M    M
 19000   -9.7  14.5   060    3    2   5.8   3.2   33.6  92.5     1.2      M    M
 18500   -8.5  16.7   070    4    2   9.4   5.1   33.4  92.0     1.0      M    M
 18000   -7.1  19.2   080    5    3   9.0   5.0   33.2  91.7     0.8      M    M
 17500   -5.1  22.8   090    7    4   9.0   4.9   33.0  91.3     0.6      M    M
 17000   -3.8  25.2   090    8    4   9.0   4.9   32.8  91.1     0.5      M    M
 16500   -2.4  27.7   095    9    5   9.0   4.9   32.7  90.9     0.4      M    M
 16000   -1.1  30.0   095   10    5   9.3   5.1   32.7  90.8     0.3      M    M
 15500    0.3  32.5   095    8    4   9.4   5.2   32.6  90.7     0.2      M    M
 15000    1.7  35.1   090    6    3   9.4   5.2   32.5  90.6     0.2      M    M
 14500    3.0  37.4   085    4    2   9.2   5.1   32.5  90.5     0.1      M    M
 14000    4.4  39.9   075    2    1   8.8   4.8   32.4  90.3    -0.0    767  3.9
 13500    5.7  42.3   075    1    1   8.8   4.8   32.2  90.0    -0.2    713  3.6
 13000    6.9  44.4   075    1    0   7.2   3.9   32.0  89.6    -0.4    661  3.4
 12500    7.9  46.2   000    0    0   7.9   4.4   31.5  88.8    -0.9    618  3.1
 12000    9.1  48.4   000    0    0   8.2   4.5   31.3  88.3    -1.2    567  2.9
 11500   10.3  50.5   195    5    3   8.2   4.5   31.0  87.8    -1.4    517  2.6
 11000   11.5  52.7   195   10    5   8.2   4.5   30.8  87.4    -1.7    466  2.4
 10500   12.6  54.7   185   11    6   7.3   4.0   30.5  86.9    -2.0    416  2.1
 10250   13.1  55.6   180   12    6   6.4   3.5   30.3  86.5    -2.3    394  2.0
 10000   13.6  56.5   180   12    6   6.7   3.7   30.0  86.0    -2.5    372  1.9
  9750   14.1  57.4   175   13    7   6.6   3.6   29.7  85.5    -2.8    351  1.8
  9500   14.6  58.3   175   14    7   6.7   3.7   29.5  85.1    -3.0    329  1.7
  9250   15.0  59.0   170   14    7   6.3   3.5   29.3  84.7    -3.3    307  1.6
  9000   15.5  59.9   170   15    8   7.8   4.3   29.0  84.3    -3.5    285  1.4
  8750   16.2  61.2   170   16    8   9.7   5.3   29.0  84.2    -3.6    258  1.3
  8500   16.9  62.4   165   16    8   9.5   5.2   29.0  84.1    -3.6    229  1.2
  8250   17.6  63.7   165   17    9   9.8   5.4   29.0  84.1    -3.7    201  1.0
  8000   18.3  64.9   165   18    9   9.0   4.9   29.0  84.1    -3.7    172  0.9
  7750   18.7  65.7   160   18    9  -1.5  -0.8   28.6  83.5    -4.1    154  0.8
  7500   18.3  64.9   155   17    9  -2.0  -1.1   27.5  81.5    -5.2    157  0.8
  7250   18.6  65.5   150   17    9   7.7   4.2   27.1  80.7    -5.6    141  0.7
  7000   19.2  66.6   140   17    9   8.5   4.6   26.9  80.5    -5.8    116  0.6
  6750   19.8  67.6   140   17    9   8.1   4.4   26.8  80.3    -5.9     91  0.5
  6500   20.4  68.7   140   18    9   8.9   4.9   26.7  80.1    -6.0     65  0.3
  6250   21.0  69.8   135   18    9   6.0   3.3   26.6  79.9    -6.2     40  0.2
  6000   21.2  70.2   135   19   10   1.2   0.6   26.1  79.0    -6.7     26  0.1
  5750   21.2  70.2   130   18    9  -0.7  -0.4   25.4  77.7    -7.5     19  0.1
  5500   21.2  70.2   125   17    9   3.2   1.7   24.7  76.4    -8.2     12  0.1
  5250   21.8  71.2   120   16    8  10.3   5.7   24.5  76.1    -8.4      M    M
  5000   22.4  72.3   115   15    8   0.3   0.2   24.3  75.8    -8.5      M    M

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

           08/22/2017 at 0900 MDT          |       08/22/2017 at 1200 MDT
                                           |
K index... +27.7  LI... -2.0               | K index... +28.1  LI... -3.2
CAPE... +213.9  CIN... -24.7               | CAPE... +480.8  CIN... -43.3
                                           |
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 -63.4 -82.1  250  22 11   2.4   1.3 | -63.7 -82.7  255  25 13   1.9   1.0
 45000 -57.8 -72.0  250  32 17   5.8   3.2 | -58.5 -73.3  250  36 19   6.1   3.4
 40000 -49.5 -57.1  250  40 21   3.8   2.1 | -49.8 -57.6  250  43 22   4.1   2.2
 38000 -47.2 -53.0  255  29 15   3.8   2.1 | -47.3 -53.1  250  34 18   4.1   2.2
 36000 -45.0 -49.0  255  19 10   3.4   1.9 | -44.9 -48.8  250  25 13   3.7   2.0
 34000 -41.3 -42.3  260  13  7   6.6   3.6 | -41.1 -42.0  255  16  8   6.7   3.7
 32000 -36.9 -34.4  265   8  4   7.2   3.9 | -36.6 -33.9  270   5  3   7.3   4.0
 30000 -31.9 -25.4  230   6  3   8.5   4.6 | -31.6 -24.9  245   4  2   8.5   4.7
 29000 -29.4 -20.9  210   6  3   8.5   4.6 | -29.1 -20.4  230   5  2   8.5   4.7
 28000 -26.9 -16.4  195   7  3   7.8   4.3 | -26.7 -16.1  220   5  3   7.5   4.1
 27000 -24.6 -12.3  190   8  4   7.8   4.3 | -24.4 -11.9  205   6  3   7.6   4.2
 26000 -22.3  -8.1  185   9  5   7.8   4.3 | -22.2  -8.0  200   8  4   7.6   4.2
 25000 -19.9  -3.8  185  10  5   7.3   4.0 | -20.0  -4.0  195   9  5   7.3   4.0
 24000 -18.0  -0.4  175   9  5   6.3   3.5 | -17.9  -0.2  185   9  5   6.9   3.8
 23000 -16.2   2.8  160   9  4   6.4   3.5 | -15.9   3.4  180  10  5   6.9   3.8
 22000 -14.3   6.3  145   9  4   6.4   3.5 | -13.9   7.0  170  10  5   6.3   3.5
 21000 -12.5   9.5  130   8  4   6.4   3.5 | -12.2  10.0  160  11  6   5.8   3.2
 20000 -10.6  12.9  110   8  4   6.4   3.5 | -10.5  13.1  150  13  7   5.8   3.2
 19500  -9.7  14.5  105   8  4   6.5   3.5 |  -9.6  14.7  145  14  7   5.9   3.2
 19000  -8.7  16.3  100   9  4   7.1   3.9 |  -8.6  16.5  140  14  7   8.2   4.5
 18500  -7.1  19.2  095   9  5   7.0   3.9 |  -6.8  19.8  135  15  8   8.0   4.4
 18000  -6.0  21.2  095  10  5   8.0   4.4 |  -5.6  21.9  130  15  8   7.9   4.3
 17500  -4.9  23.2  095  11  5   7.9   4.3 |  -4.4  24.1  125  16  8   7.9   4.3
 17000  -3.8  25.2  095  11  6   7.7   4.2 |  -3.2  26.2  125  16  8   7.7   4.2
 16500  -2.7  27.1  095  11  6   7.6   4.2 |  -2.2  28.0  120  16  8   7.6   4.2
 16000  -1.6  29.1  095  12  6   7.7   4.2 |  -1.1  30.0  120  16  8   7.7   4.2
 15500  -0.4  31.3  095  12  6   7.8   4.3 |  -0.1  31.8  120  15  8   7.6   4.2
 15000   0.7  33.3  095  12  6   7.9   4.3 |   1.0  33.8  120  14  7   7.7   4.2
 14500   1.8  35.2  100  11  6   7.6   4.2 |   2.0  35.6  120  13  7   7.4   4.1
 14000   2.8  37.0  105  11  5   7.6   4.2 |   3.1  37.6  120  12  6   7.4   4.1
 13500   3.9  39.0  110  10  5   8.2   4.5 |   4.2  39.6  120  11  6   8.0   4.4
 13000   5.1  41.2  115   8  4   8.3   4.5 |   5.4  41.7  120   9  5   8.1   4.4
 12500   6.3  43.3  120   7  4   8.6   4.7 |   6.5  43.7  120   8  4   7.2   3.9
 12000   7.6  45.7  125   6  3   8.7   4.7 |   7.5  45.5  120   7  3   6.9   3.8
 11500   8.8  47.8  140   5  3   7.8   4.3 |   8.5  47.3  130   5  3   6.7   3.7
 11000   9.9  49.8  155   4  2   7.2   3.9 |   9.4  48.9  145   3  2   6.6   3.6
 10500  10.9  51.6  175   4  2   5.5   3.0 |  10.4  50.7  180   2  1   5.6   3.1
 10250  11.3  52.3  180   4  2   6.0   3.3 |  10.8  51.4  195   2  1   6.7   3.6
 10000  11.9  53.4  185   4  2   8.5   4.6 |  11.4  52.5  220   3  1   8.6   4.7
  9750  12.5  54.5  190   4  2   8.3   4.5 |  12.0  53.6  240   4  2   8.2   4.5
  9500  13.1  55.6  195   4  2   7.4   4.0 |  12.6  54.7  250   4  2   7.6   4.2
  9250  13.6  56.5  195   4  2   6.5   3.6 |  13.1  55.6  255   5  3   7.2   3.9
  9000  14.1  57.4  195   5  2   7.7   4.2 |  13.6  56.5  255   6  3   8.9   4.9
  8750  14.7  58.5  195   5  3   8.2   4.5 |  14.3  57.7  260   7  3   9.8   5.4
  8500  15.3  59.5  195   6  3   7.1   3.9 |  15.0  59.0  260   7  4   9.5   5.2
  8250  15.8  60.4  195   6  3   6.3   3.5 |  15.7  60.3  260   7  4   9.1   5.0
  8000  16.3  61.3  190   7  4   7.6   4.2 |  16.4  61.5  260   7  4  10.3   5.7
  7750  16.8  62.2  190   8  4   7.4   4.1 |  17.2  63.0  260   7  4  11.1   6.1
  7500  17.3  63.1  190   8  4   5.1   2.8 |  18.0  64.4  260   7  4  10.0   5.5
  7250  17.6  63.7  185   9  5   4.1   2.2 |  18.7  65.7  260   7  4   9.7   5.3
  7000  18.0  64.4  180   9  5   5.5   3.0 |  19.4  66.9  260   7  4  10.2   5.6
  6750  18.4  65.1  180  10  5   4.4   2.4 |  20.2  68.4  260   7  4  10.6   5.8
  6500  18.5  65.3  175   9  4   2.4   1.3 |  21.0  69.8  260   7  4  10.7   5.9
  6250  18.7  65.7  170   8  4   2.6   1.4 |  21.8  71.2  260   7  4  10.5   5.8
  6000  18.9  66.0  165   7  3   3.5   1.9 |  22.6  72.7  260   7  4  11.1   6.1
  5750  19.4  66.9  160   6  3  11.1   6.1 |  23.6  74.5  260   7  4  18.8  10.3
  5500  20.6  69.1  160   5  3  20.6  11.3 |  25.4  77.7  265   7  4  29.7  16.3
  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

           08/22/2017 at 1500 MDT          |       08/22/2017 at 1800 MDT
                                           |
K index... +25.9  LI... -2.9               | K index... +27.0  LI... -2.6
CAPE... +649.8  CIN... -74.0               | CAPE... +530.5  CIN... -91.5
                                           |
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 -63.8 -82.8  260  23 12   1.7   0.9 | -64.3 -83.7  260  25 13   1.5   0.8
 45000 -58.7 -73.7  255  34 17   6.4   3.5 | -59.5 -75.1  255  37 19   6.1   3.4
 40000 -49.6 -57.3  250  42 22   4.1   2.2 | -50.5 -58.9  255  41 21   5.1   2.8
 38000 -47.1 -52.8  245  34 17   4.1   2.2 | -47.5 -53.5  245  31 16   5.1   2.8
 36000 -44.7 -48.5  235  27 14   3.9   2.1 | -44.4 -47.9  230  23 12   5.1   2.8
 34000 -40.9 -41.6  220  18  9   6.7   3.7 | -40.0 -40.0  205  19 10   7.7   4.2
 32000 -36.4 -33.5  175  13  6   7.4   4.1 | -34.7 -30.5  180  20 10   8.4   4.6
 30000 -31.3 -24.3  170  11  5   8.5   4.7 | -30.0 -22.0  185  16  8   8.0   4.4
 29000 -28.8 -19.8  165  10  5   8.6   4.7 | -27.7 -17.9  190  14  7   8.0   4.4
 28000 -26.3 -15.3  165   9  5   8.1   4.4 | -25.4 -13.7  200  12  6   6.5   3.6
 27000 -23.9 -11.0  170  10  5   8.2   4.5 | -23.4 -10.1  210  12  6   6.6   3.6
 26000 -21.4  -6.5  175  12  6   8.2   4.5 | -21.5  -6.7  225  12  6   6.7   3.7
 25000 -19.0  -2.2  175  13  7   7.4   4.1 | -19.5  -3.1  235  13  7   7.0   3.8
 24000 -17.1   1.2  180  13  7   6.4   3.5 | -17.3   0.9  240  13  6   7.4   4.1
 23000 -15.3   4.5  180  12  6   6.5   3.5 | -15.2   4.6  245  13  6   7.4   4.1
 22000 -13.4   7.9  185  12  6   6.7   3.7 | -13.0   8.6  250  13  6   7.1   3.9
 21000 -11.4  11.5  180  12  6   7.0   3.8 | -11.0  12.2  245  10  5   6.8   3.7
 20000  -9.3  15.3  175  12  6   7.0   3.8 |  -9.1  15.6  245   8  4   6.8   3.7
 19500  -8.3  17.1  170  12  6   7.0   3.8 |  -8.1  17.4  240   7  4   6.8   3.8
 19000  -6.9  19.6  165  12  6   5.9   3.3 |  -7.2  19.0  240   6  3   5.8   3.2
 18500  -6.1  21.0  160  12  6   5.8   3.2 |  -5.9  21.4  225   5  2   5.9   3.2
 18000  -5.0  23.0  155  13  7   7.9   4.3 |  -5.0  23.0  215   5  2   6.6   3.6
 17500  -3.9  25.0  155  13  7   7.7   4.2 |  -4.0  24.8  205   5  3   6.5   3.6
 17000  -2.7  27.1  155  13  7   7.8   4.3 |  -3.1  26.4  200   5  3   7.1   3.9
 16500  -1.6  29.1  155  14  7   7.9   4.3 |  -2.0  28.4  195   5  3   7.4   4.1
 16000  -0.4  31.3  155  14  7   7.9   4.3 |  -0.9  30.4  190   6  3   7.5   4.1
 15500   0.7  33.3  155  14  7   7.8   4.3 |   0.2  32.4  185   6  3   7.6   4.2
 15000   1.8  35.2  155  13  7   7.8   4.3 |   1.3  34.3  185   6  3   7.6   4.2
 14500   3.0  37.4  160  13  7   8.0   4.4 |   2.5  36.5  180   7  3   8.3   4.5
 14000   4.1  39.4  160  13  6   8.0   4.4 |   3.7  38.7  180   7  4   8.3   4.5
 13500   5.3  41.5  160  12  6   7.7   4.2 |   4.9  40.8  175   7  4   8.2   4.5
 13000   6.4  43.5  165  11  6   7.7   4.2 |   6.1  43.0  175   8  4   8.2   4.5
 12500   7.5  45.5  165  10  5   7.9   4.3 |   7.4  45.3  170   8  4   8.3   4.5
 12000   8.7  47.7  165   8  4   8.0   4.4 |   8.6  47.5  170   8  4   8.3   4.6
 11500   9.8  49.6  165   7  3   7.4   4.1 |   9.8  49.6  170   9  4   8.1   4.5
 11000  10.8  51.4  170   6  3   6.8   3.8 |  10.9  51.6  170   9  5   7.7   4.2
 10500  11.7  53.1  170   5  2   6.5   3.6 |  12.1  53.8  170  10  5   3.9   2.2
 10250  12.2  54.0  175   4  2   6.6   3.6 |  12.2  54.0  175  10  5   5.0   2.7
 10000  12.7  54.9  185   4  2   7.1   3.9 |  12.9  55.2  175  11  6  10.8   5.9
  9750  13.2  55.8  205   3  2   7.1   3.9 |  13.6  56.5  175  11  6  10.0   5.5
  9500  13.7  56.7  225   3  2   6.7   3.7 |  14.3  57.7  175  12  6   8.1   4.5
  9250  14.1  57.4  245   4  2   6.4   3.5 |  14.7  58.5  175  12  6   5.9   3.2
  9000  14.6  58.3  260   5  3   6.7   3.7 |  15.2  59.4  170  12  6   7.7   4.2
  8750  15.0  59.0  270   6  3   6.8   3.7 |  15.7  60.3  170  13  7   8.4   4.6
  8500  15.5  59.9  275   8  4   6.4   3.5 |  16.2  61.2  170  13  7   7.2   3.9
  8250  15.9  60.6  275   9  4   6.0   3.3 |  16.7  62.1  170  14  7   6.5   3.5
  8000  16.3  61.3  280  10  5   6.6   3.6 |  17.2  63.0  165  14  7   6.5   3.6
  7750  16.8  62.2  280  10  5   7.6   4.1 |  17.6  63.7  165  15  8   6.1   3.3
  7500  17.4  63.3  280  11  6   8.1   4.5 |  18.0  64.4  165  16  8   5.7   3.1
  7250  17.9  64.2  280  11  6   8.1   4.5 |  18.4  65.1  165  17  9   5.7   3.1
  7000  18.5  65.3  280  12  6   8.7   4.8 |  18.8  65.8  165  18  9   5.2   2.9
  6750  19.2  66.6  280  12  6  10.2   5.6 |  19.2  66.6  160  18  9   6.2   3.4
  6500  20.0  68.0  280  12  6  10.7   5.9 |  19.7  67.5  165  18  9   8.0   4.4
  6250  20.8  69.4  280  12  6  10.3   5.7 |  20.2  68.4  165  18  9   8.1   4.4
  6000  21.5  70.7  280  12  6  11.1   6.1 |  20.8  69.4  165  17  9   8.3   4.6
  5750  22.6  72.7  280  12  6  19.5  10.7 |  21.5  70.7  165  17  9  13.3   7.3
  5500  24.5  76.1  280  12  6  31.3  17.2 |  22.8  73.0  165  16  8  20.6  11.3
  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
________________________________________________________________________________

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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