Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 201302
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0702 MDT Tuesday, September 20, 2016

This forecast is for Tuesday, September 20, 2016:

If the trigger temperature of 84.5 F/29.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 277 ft/min (1.4 m/s)
   Maximum height of thermals.................. 10823 ft MSL (5984 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 C
Time of trigger temperature.................... 1400 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................. 7013 ft MSL (2174 ft AGL)
Thermal soaring outlook for Wednesday 09/21.... Good

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

Remarks...

Sunrise/Sunset.................... 07:00:29 / 19:15:01 MDT
Total possible sunshine........... 12 hr 14 min 32 sec (734 min 32 sec)
Altitude of sun at 13:07:16 MDT... 51.59 degrees

Upper air data from rawinsonde observation taken on 09/20/2016 at 0600 MDT

Freezing level.................. 15517 ft MSL (10678 ft AGL)
Convective condensation level... 21432 ft MSL (16593 ft AGL)
Lifted condensation level....... 19032 ft MSL (14193 ft AGL)
Lifted index.................... +3.5
K index......................... +4.4

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  -66.4 -87.5   250   56   29   7.0   3.9   84.6 184.3    31.6      M    M
 45000  -62.4 -80.3   260   63   33   5.0   2.8   65.7 150.2    22.2      M    M
 40000  -54.6 -66.3   260   79   41   8.7   4.8   55.2 131.3    16.8      M    M
 38000  -50.4 -58.7   255   75   39   7.1   3.9   52.7 126.9    15.5      M    M
 36000  -45.3 -49.5   255   65   34   9.5   5.2   51.8 125.2    15.3      M    M
 34000  -39.9 -39.8   255   56   29   8.9   4.9   51.0 123.8    15.1      M    M
 32000  -34.3 -29.7   245   41   21   7.9   4.3   49.7 121.5    14.5      M    M
 30000  -29.9 -21.8   235   36   18   7.6   4.1   47.8 118.1    13.4      M    M
 29000  -27.7 -17.9   225   34   18   6.8   3.7   46.9 116.3    12.8      M    M
 28000  -25.7 -14.3   220   33   17   4.4   2.4   45.8 114.4    12.1      M    M
 27000  -25.0 -13.0   220   28   14   5.4   2.9   43.0 109.4    10.0      M    M
 26000  -22.8  -9.0   225   23   12   8.4   4.6   42.1 107.8     9.5      M    M
 25000  -20.5  -4.9   230   18    9   3.6   2.0   41.3 106.4     8.9      M    M
 24000  -19.4  -2.9   235   23   12  10.4   5.7   39.0 102.2     7.2      M    M
 23000  -17.2   1.0   235   27   14   6.9   3.8   38.2 100.7     6.6      M    M
 22000  -15.0   5.0   240   31   16   9.0   5.0   37.3  99.1     5.9      M    M
 21000  -12.6   9.3   240   29   15   5.7   3.1   36.7  98.1     5.5      M    M
 20000  -10.1  13.8   240   26   13   8.5   4.6   36.1  97.0     5.1      M    M
 19500   -8.9  16.0   240   25   13   8.5   4.7   35.9  96.6     4.9      M    M
 19000   -7.7  18.1   240   24   12   7.8   4.3   35.6  96.1     4.7      M    M
 18500   -6.5  20.3   240   22   11   7.9   4.3   35.2  95.4     4.4      M    M
 18000   -5.3  22.5   240   20   10   8.0   4.4   34.9  94.9     4.2      M    M
 17500   -4.2  24.4   240   18    9   6.7   3.7   34.5  94.1     3.9      M    M
 17000   -2.7  27.1   245   15    8   6.2   3.4   33.8  92.8     3.2      M    M
 16500   -1.9  28.6   245   14    7   5.9   3.2   33.1  91.5     2.5      M    M
 16000   -1.0  30.2   245   12    6   8.2   4.5   32.6  90.6     2.0      M    M
 15500    0.3  32.5   245   11    6   8.6   4.7   32.3  90.2     1.8      M    M
 15000    1.5  34.7   245   11    6   8.7   4.8   32.2  89.9     1.6      M    M
 14500    2.8  37.0   240   10    5   8.3   4.6   32.0  89.6     1.4      M    M
 14000    4.1  39.4   240   10    5   8.2   4.5   31.7  89.1     1.2      M    M
 13500    5.4  41.7   235    9    5   8.4   4.6   31.5  88.7     1.1      M    M
 13000    6.6  43.9   235    9    5   8.5   4.7   31.3  88.3     0.8      M    M
 12500    7.9  46.2   230    8    4   8.6   4.7   31.1  88.0     0.6      M    M
 12000    9.1  48.4   225    8    4   8.6   4.7   30.9  87.7     0.5      M    M
 11500   10.4  50.7   230    8    4   8.6   4.7   30.7  87.3     0.2      M    M
 11000   11.6  52.9   240    7    4   8.3   4.5   30.5  86.9     0.0      M    M
 10500   13.0  55.4   245    7    4   8.1   4.4   30.3  86.5    -0.1    440  2.2
 10250   13.6  56.5   245    7    4   7.9   4.4   30.1  86.2    -0.2    414  2.1
 10000   14.2  57.6   250    7    4   8.4   4.6   30.0  86.0    -0.3    388  2.0
  9750   14.8  58.6   250    7    4   8.6   4.7   29.9  85.8    -0.4    362  1.8
  9500   15.4  59.7   250    7    4   8.5   4.7   29.8  85.7    -0.5    336  1.7
  9250   16.1  61.0   255    7    4   8.5   4.7   29.7  85.5    -0.6    310  1.6
  9000   16.7  62.1   255    7    4   8.6   4.7   29.7  85.4    -0.7    284  1.4
  8750   17.3  63.1   250    6    3   8.6   4.7   29.6  85.2    -0.8    258  1.3
  8500   17.9  64.2   245    4    2   8.6   4.7   29.5  85.0    -0.9    232  1.2
  8250   18.5  65.3   240    3    2   8.6   4.7   29.4  84.9    -1.1    206  1.0
  8000   19.2  66.6   220    2    1   8.5   4.7   29.3  84.7    -1.2    180  0.9
  7750   19.8  67.6   170    4    2   8.9   4.9   29.2  84.5    -1.3    154  0.8
  7500   20.4  68.7   155    6    3   7.5   4.1   29.1  84.4    -1.4    128  0.7
  7250   20.7  69.3   150    9    5   0.1   0.0   28.7  83.6    -1.8    112  0.6
  7000   20.4  68.7   145   12    6  -4.2  -2.3   27.7  81.8    -2.8    112  0.6
  6750   20.2  68.4   145   11    6  -2.3  -1.3   26.7  80.1    -3.8    113  0.6
  6500   20.1  68.2   140    9    5   2.7   1.5   25.9  78.7    -4.6    107  0.5
  6250   20.5  68.9   135    7    4   5.9   3.2   25.6  78.0    -5.0     88  0.4
  6000   20.9  69.6   130    6    3   5.1   2.8   25.2  77.4    -5.3     69  0.4
  5750   21.3  70.3   120    5    3   5.1   2.8   24.9  76.8    -5.7     50  0.3
  5500   21.7  71.1   120    5    3   5.8   3.2   24.6  76.2    -6.1     31  0.2
  5250   21.4  70.5   115    5    3 -24.5 -13.4   23.5  74.3    -7.1     33  0.2
  5000   17.7  63.9   110    5    3 -67.1 -36.8   19.1  66.4   -11.6    137  0.7

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

           09/20/2016 at 0900 MDT          |       09/20/2016 at 1200 MDT
                                           |
K index... +2.6  LI... +274.1              | K index... +8.8  LI... +275.4
CAPE... 0.0  CIN... -11.3                  | CAPE... 0.0  CIN... -0.3
                                           |
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 -66.0 -86.8  270  45 23   2.3   1.3 | -66.2 -87.2  265  49 25   1.9   1.1
 45000 -61.7 -79.1  265  59 30   4.3   2.3 | -62.2 -80.0  260  63 32   4.0   2.2
 40000 -54.3 -65.7  260  82 42   7.8   4.3 | -55.1 -67.2  255  76 39   9.4   5.2
 38000 -49.6 -57.3  255  74 38   7.8   4.3 | -49.4 -56.9  250  71 36   9.5   5.2
 36000 -44.9 -48.8  250  67 34   7.9   4.3 | -43.8 -46.8  245  65 34   9.7   5.3
 34000 -39.7 -39.5  250  57 29   8.6   4.7 | -38.9 -38.0  245  63 32   8.0   4.4
 32000 -34.6 -30.3  250  48 24   8.5   4.7 | -34.1 -29.4  245  61 31   7.8   4.3
 30000 -29.9 -21.8  245  40 21   7.6   4.2 | -29.3 -20.7  250  56 29   6.9   3.8
 29000 -27.7 -17.9  245  37 19   7.6   4.2 | -27.3 -17.1  250  53 27   6.9   3.8
 28000 -25.4 -13.7  240  34 17   6.3   3.5 | -25.2 -13.4  250  50 26   7.1   3.9
 27000 -23.9 -11.0  240  29 15   5.2   2.8 | -23.2  -9.8  250  45 23   7.1   3.9
 26000 -22.4  -8.3  235  25 13   5.2   2.8 | -21.1  -6.0  245  39 20   7.1   3.9
 25000 -20.8  -5.4  225  22 11   5.2   2.8 | -19.0  -2.2  245  34 18   6.7   3.7
 24000 -19.3  -2.7  225  20 10   5.1   2.8 | -17.9  -0.2  240  28 14   3.2   1.7
 23000 -17.8  -0.0  225  18 10   5.1   2.8 | -16.9   1.6  240  22 11   3.2   1.7
 22000 -15.9   3.4  230  17  9   5.6   3.1 | -16.0   3.2  230  16  8   4.1   2.2
 21000 -14.2   6.4  235  16  8   5.8   3.2 | -14.1   6.6  230  15  8   6.9   3.8
 20000 -12.5   9.5  245  16  8   5.9   3.2 | -12.1  10.2  230  16  8   6.9   3.8
 19500 -11.6  11.1  250  16  8   7.4   4.1 | -11.1  12.0  230  16  8   7.4   4.0
 19000 -10.0  14.0  250  16  8  11.1   6.1 | -10.3  13.5  230  15  8   2.8   1.5
 18500  -8.3  17.1  250  17  9  11.2   6.1 |  -9.9  14.2  230  12  6   3.2   1.7
 18000  -6.7  19.9  250  17  9   9.6   5.2 |  -8.8  16.2  225   8  4   8.6   4.7
 17500  -5.3  22.5  250  16  8   9.4   5.2 |  -7.6  18.3  230   9  4   8.5   4.7
 17000  -3.9  25.0  245  16  8   9.0   4.9 |  -6.3  20.7  230   9  4   9.8   5.4
 16500  -2.6  27.3  245  16  8   8.3   4.6 |  -4.6  23.7  235  10  5  11.1   6.1
 16000  -1.4  29.5  245  16  8   8.3   4.5 |  -2.9  26.8  235  11  6  11.1   6.1
 15500  -0.1  31.8  245  15  8   9.1   5.0 |  -1.3  29.7  235  12  6  10.0   5.5
 15000   1.3  34.3  245  15  8   9.0   4.9 |   0.2  32.4  240  14  7  10.1   5.6
 14500   2.6  36.7  240  15  8   9.1   5.0 |   1.6  34.9  240  15  8   9.6   5.2
 14000   4.0  39.2  240  15  8   9.1   5.0 |   3.0  37.4  240  17  9   9.6   5.2
 13500   5.3  41.5  235  15  8   8.8   4.8 |   4.5  40.1  240  18  9   9.5   5.2
 13000   6.6  43.9  235  14  7   8.6   4.7 |   5.9  42.6  240  19 10   9.4   5.2
 12500   7.9  46.2  235  14  7   8.4   4.6 |   7.3  45.1  240  20 10   9.2   5.1
 12000   9.1  48.4  235  14  7   8.2   4.5 |   8.6  47.5  240  20 10   9.0   4.9
 11500  10.3  50.5  235  14  7   8.1   4.5 |  10.0  50.0  240  21 11   8.7   4.8
 11000  11.5  52.7  235  13  7   7.7   4.2 |  11.3  52.3  240  21 11   8.1   4.5
 10500  12.7  54.9  235  12  6   4.6   2.5 |  12.5  54.5  240  20 11   4.2   2.3
 10250  12.9  55.2  235  12  6   4.5   2.5 |  12.7  54.9  240  20 10   5.2   2.9
 10000  13.5  56.3  230  11  6   9.7   5.3 |  13.4  56.1  240  19 10  11.1   6.1
  9750  14.2  57.6  230  10  5   9.7   5.3 |  14.2  57.6  240  18 10  10.2   5.6
  9500  14.9  58.8  230  10  5   8.0   4.4 |  14.9  58.8  240  18  9   8.1   4.4
  9250  15.4  59.7  225   9  5   5.6   3.1 |  15.4  59.7  240  17  8   5.4   3.0
  9000  15.8  60.4  220   8  4   7.6   4.1 |  15.8  60.4  240  15  8   7.1   3.9
  8750  16.5  61.7  215   7  4   9.2   5.0 |  16.4  61.5  240  14  7   7.8   4.3
  8500  17.1  62.8  210   7  4   8.1   4.4 |  17.0  62.6  240  12  6   6.7   3.7
  8250  17.7  63.9  205   7  4   7.4   4.0 |  17.4  63.3  240  11  6   6.1   3.3
  8000  18.3  64.9  200   7  4   7.7   4.2 |  17.9  64.2  235  10  5   5.9   3.2
  7750  18.8  65.8  195   8  4   7.5   4.1 |  18.3  64.9  235   9  4   5.6   3.1
  7500  19.3  66.7  190   8  4   4.4   2.4 |  18.7  65.7  230   8  4   6.6   3.6
  7250  19.5  67.1  180  10  5   2.3   1.2 |  19.2  66.6  225   7  4   7.2   3.9
  7000  19.7  67.5  175  11  6   2.9   1.6 |  19.7  67.5  220   7  3   6.7   3.7
  6750  19.9  67.8  170  12  6   1.1   0.6 |  20.2  68.4  215   7  3   8.0   4.4
  6500  19.9  67.8  170  12  6  -0.9  -0.5 |  20.9  69.6  210   6  3  10.1   5.5
  6250  19.8  67.6  160  11  5   0.2   0.1 |  21.7  71.1  215   6  3  10.1   5.5
  6000  19.7  67.5  155   9  5  -4.1  -2.3 |  22.4  72.3  215   6  3  10.6   5.8
  5750  19.2  66.6  150   9  5  -6.0  -3.3 |  23.3  73.9  215   6  3  14.6   8.0
  5500  19.0  66.2  140   7  3   4.1   2.2 |  24.6  76.3  215   6  3  19.5  10.7
  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

           09/20/2016 at 1500 MDT          |       09/20/2016 at 1800 MDT
                                           |
K index... +17.6  LI... +274.5             | K index... +23.8  LI... +274.3
CAPE... 0.0  CIN... -0.0                   | CAPE... 0.0  CIN... -0.6
                                           |
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 -66.5 -87.7  260  51 26   1.8   1.0 | -66.3 -87.3  265  48 25   1.8   1.0
 45000 -62.6 -80.7  260  66 34   4.7   2.6 | -62.5 -80.5  260  61 31   4.4   2.4
 40000 -54.6 -66.3  255  80 41   8.3   4.6 | -54.6 -66.3  245  74 38   9.3   5.1
 38000 -49.6 -57.3  255  77 40   8.3   4.6 | -49.0 -56.2  240  72 37   9.3   5.1
 36000 -44.6 -48.3  250  75 39   8.3   4.6 | -43.4 -46.1  235  70 36   9.4   5.1
 34000 -38.9 -38.0  245  70 36   9.5   5.2 | -38.3 -36.9  235  64 33   8.5   4.7
 32000 -33.2 -27.8  245  64 33   9.4   5.2 | -33.2 -27.8  235  57 30   8.3   4.6
 30000 -29.3 -20.7  250  59 30   5.8   3.2 | -28.9 -20.0  245  52 27   6.9   3.8
 29000 -27.2 -17.0  255  56 29   5.8   3.2 | -26.3 -15.3  255  50 26   6.9   3.8
 28000 -25.4 -13.7  260  53 27   7.4   4.0 | -24.2 -11.6  265  48 25   6.9   3.8
 27000 -23.1  -9.6  255  49 25   7.5   4.1 | -22.2  -8.0  265  42 22   6.9   3.8
 26000 -20.9  -5.6  255  44 23   7.5   4.1 | -20.1  -4.2  265  36 19   6.9   3.8
 25000 -18.7  -1.7  255  39 20   7.1   3.9 | -18.0  -0.4  265  30 16   6.6   3.6
 24000 -16.9   1.6  250  35 18   6.2   3.4 | -16.5   2.3  260  26 14   4.9   2.7
 23000 -15.1   4.8  245  31 16   6.2   3.4 | -15.2   4.6  255  23 12   5.0   2.7
 22000 -13.3   8.1  235  27 14   5.2   2.9 | -13.8   7.2  250  19 10   5.0   2.7
 21000 -12.3   9.9  235  24 12   3.3   1.8 | -12.4   9.7  240  17  9   4.6   2.5
 20000 -11.3  11.7  235  21 11   3.3   1.8 | -11.1  12.0  225  16  8   4.5   2.5
 19500 -10.8  12.6  235  20 10   2.9   1.6 | -10.4  13.3  220  15  8   4.4   2.4
 19000 -10.1  13.8  235  19 10   7.9   4.3 |  -9.7  14.5  210  15  8   6.4   3.5
 18500  -9.0  15.8  235  20 10   7.4   4.0 |  -8.8  16.2  210  15  8   6.3   3.5
 18000  -7.9  17.8  230  20 10   6.6   3.6 |  -7.8  18.0  205  15  8   6.6   3.6
 17500  -7.1  19.2  230  17  9   5.8   3.2 |  -6.8  19.8  205  14  7   7.0   3.9
 17000  -6.2  20.8  230  15  8   5.8   3.2 |  -5.8  21.6  210  13  7   7.2   3.9
 16500  -5.3  22.5  230  13  7   6.8   3.7 |  -4.9  23.2  210  13  7   5.7   3.1
 16000  -4.3  24.3  230  13  7   6.6   3.6 |  -4.1  24.6  215  12  6   5.8   3.2
 15500  -3.2  26.2  225  12  6   9.4   5.1 |  -3.2  26.2  215  11  6   6.1   3.3
 15000  -1.7  28.9  225  12  6   9.9   5.4 |  -2.3  27.9  210  11  6   6.2   3.4
 14500  -0.2  31.6  225  12  6  10.2   5.6 |  -1.4  29.5  210  11  6   7.0   3.9
 14000   2.2  36.0  220  12  6  10.5   5.8 |   0.5  32.9  215  11  6   8.5   4.7
 13500   3.7  38.7  220  12  6   9.8   5.4 |   1.9  35.4  215  11  6   9.7   5.3
 13000   5.2  41.4  220  12  6   9.7   5.3 |   3.4  38.1  215  11  6  10.1   5.5
 12500   6.6  43.9  220  12  6   9.6   5.3 |   4.9  40.8  215  12  6  10.1   5.5
 12000   8.1  46.6  220  12  6   9.5   5.2 |   6.4  43.5  215  12  6  10.1   5.5
 11500   9.5  49.1  225  12  6   9.0   4.9 |   7.9  46.2  220  12  6   9.9   5.5
 11000  10.8  51.4  230  12  6   8.7   4.8 |   9.4  48.9  220  12  6   9.6   5.3
 10500  12.0  53.6  235  12  6   4.5   2.5 |  10.9  51.6  220  12  6   5.0   2.7
 10250  12.3  54.1  240  12  6   6.8   3.7 |  11.1  52.0  220  12  6   6.7   3.7
 10000  13.1  55.6  240  12  6  11.4   6.3 |  12.0  53.6  220  12  6  13.3   7.3
  9750  13.8  56.8  245  12  6  10.2   5.6 |  12.9  55.2  220  12  6  11.9   6.5
  9500  14.6  58.3  245  12  6   7.6   4.1 |  13.7  56.7  220  12  6   9.6   5.3
  9250  15.0  59.0  245  12  6   6.7   3.7 |  14.3  57.7  220  12  6   8.5   4.7
  9000  15.7  60.3  250  11  6   9.1   5.0 |  15.1  59.2  220  12  6  10.8   5.9
  8750  16.4  61.5  250  10  5   9.0   4.9 |  15.9  60.6  220  12  6  10.7   5.9
  8500  17.0  62.6  255   9  5   8.7   4.8 |  16.7  62.1  225  12  6   9.9   5.4
  8250  17.7  63.9  255   9  4   8.5   4.7 |  17.4  63.3  225  11  6   9.4   5.2
  8000  18.3  64.9  260   8  4   9.0   4.9 |  18.1  64.6  230  10  5   8.9   4.9
  7750  19.0  66.2  260   7  4   9.5   5.2 |  18.8  65.8  230   9  5   8.6   4.7
  7500  19.8  67.6  260   7  4   9.8   5.4 |  19.5  67.1  235   9  4   9.2   5.0
  7250  20.5  68.9  260   7  4   9.9   5.4 |  20.2  68.4  235   8  4   9.2   5.1
  7000  21.3  70.3  260   7  4  10.1   5.6 |  20.9  69.6  235   8  4   9.4   5.2
  6750  22.0  71.6  260   7  4  10.6   5.8 |  21.6  70.9  235   8  4   9.9   5.4
  6500  22.8  73.0  260   7  4  10.6   5.8 |  22.3  72.1  235   8  4  10.0   5.5
  6250  23.6  74.5  260   7  4  10.6   5.8 |  23.1  73.6  235   8  4  10.2   5.6
  6000  24.4  75.9  260   7  4  10.4   5.7 |  23.8  74.8  235   8  4   9.4   5.2
  5750  25.2  77.4  260   7  4  11.8   6.5 |  24.5  76.1  235   7  4   8.0   4.4
  5500  26.1  79.0  265   7  4  13.4   7.3 |  25.0  77.0  235   7  4   7.8   4.3
  5250  27.1  80.8  265   7  4  12.2   6.7 |  25.6  78.1  235   7  4   7.9   4.3
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  Note that some elevations in numerical weather prediction models
differ from actual station elevations, which can lead to data which appear
to be below ground.  Erroneous data such as these should not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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