Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 201237
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0636 MDT Saturday, September 20, 2014

This forecast is for Saturday, September 20, 2014:

If the trigger temperature of 82.2 F/27.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 538 ft/min (2.7 m/s)
   Maximum height of thermals.................. 13587 ft MSL (8748 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ 6 PM MDT
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................. 8921 ft MSL (4082 ft AGL)
Thermal soaring outlook for Sunday 09/21....... Good

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

Remarks...

Sunrise/Sunset.................... 07:00:01 / 19:15:51 MDT
Total possible sunshine........... 12 hr 15 min 50 sec (735 min 50 sec)
Altitude of sun at 13:07:27 MDT... 51.79 degrees

Upper air data from rawinsonde observation taken on 09/20/2014 at 0600 MDT

Freezing level.................. 15985 ft MSL (11146 ft AGL)
Convective condensation level... 17166 ft MSL (12327 ft AGL)
Lifted condensation level....... 16160 ft MSL (11321 ft AGL)
Lifted index.................... -0.1
K index......................... +14.5

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  -70.3 -94.5   255   52   27   3.8   2.1   77.4 171.4    26.8      M    M
 45000  -61.7 -79.1   260   65   33   4.9   2.7   66.2 151.1    21.9      M    M
 40000  -51.4 -60.5   260   66   34   6.3   3.4   59.4 138.9    18.9      M    M
 38000  -46.9 -52.4   260   65   33   7.3   4.0   57.3 135.2    18.0      M    M
 36000  -42.5 -44.5   260   63   33   7.3   4.0   55.4 131.8    17.1      M    M
 34000  -39.2 -38.6   265   48   25   3.8   2.1   51.9 125.4    15.0      M    M
 32000  -34.7 -30.5   270   25   13   6.7   3.7   49.0 120.2    13.3      M    M
 30000  -30.9 -23.6   265   25   13   7.9   4.4   46.4 115.5    11.6      M    M
 29000  -28.5 -19.3   285   26   13   8.0   4.4   45.7 114.3    11.2      M    M
 28000  -26.1 -15.0   290   23   12   8.0   4.4   44.9 112.8    10.7      M    M
 27000  -23.8 -10.8   290   20   10   6.4   3.5   44.2 111.5    10.3      M    M
 26000  -21.9  -7.4   295   17    9   6.7   3.7   42.8 109.1     9.3      M    M
 25000  -20.1  -4.2   265    5    3   3.7   2.0   41.5 106.6     8.3      M    M
 24000  -18.1  -0.6   270    5    3   7.9   4.4   40.4 104.7     7.5      M    M
 23000  -15.7   3.7   280    5    2   8.1   4.4   39.7 103.5     7.0      M    M
 22000  -13.3   8.1   285    5    2   7.7   4.2   39.1 102.4     6.6      M    M
 21000  -11.0  12.2   295    5    2   7.9   4.4   38.4 101.1     6.0      M    M
 20000   -8.8  16.2   300    5    3   7.3   4.0   37.6  99.6     5.4      M    M
 19500   -7.9  17.8   295    6    3   5.5   3.0   37.0  98.6     4.9      M    M
 19000   -7.2  19.0   295    6    3   5.0   2.7   36.1  97.1     4.1      M    M
 18500   -6.2  20.8   300    6    3   8.4   4.6   35.7  96.3     3.7      M    M
 18000   -4.9  23.2   310    6    3   7.6   4.2   35.5  95.8     3.5      M    M
 17500   -4.1  24.6   315    6    3   6.1   3.4   34.8  94.7     2.9      M    M
 17000   -2.3  27.9   325    6    3   8.5   4.7   34.4  93.9     2.5      M    M
 16500   -1.1  30.0   330    7    3   8.6   4.7   34.2  93.6     2.3      M    M
 16000    0.2  32.4   335    7    3   8.6   4.7   34.0  93.2     2.2      M    M
 15500    1.5  34.7   350    6    3   8.5   4.7   33.8  92.8     2.0      M    M
 15000    2.8  37.0   010    5    2   8.3   4.6   33.6  92.5     1.8      M    M
 14500    3.6  38.5   030    5    2   5.1   2.8   33.0  91.5     1.2      M    M
 14000    4.3  39.7   050    5    3   5.8   3.2   32.3  90.2     0.5      M    M
 13500    5.2  41.4   050    5    2   6.5   3.6   31.7  89.1    -0.2    726  3.7
 13000    6.1  43.0   045    4    2   6.6   3.6   31.2  88.2    -0.8    685  3.5
 12500    6.9  44.4   045    4    2   6.5   3.6   30.7  87.3    -1.3    643  3.3
 12000    7.9  46.2   045    4    2   8.2   4.5   30.3  86.6    -1.8    599  3.0
 11500    9.2  48.6   065    7    4   8.4   4.6   30.1  86.1    -2.0    547  2.8
 11000   10.4  50.7   075   11    6   8.4   4.6   29.9  85.8    -2.2    495  2.5
 10500   11.7  53.1   080   14    7   7.4   4.1   29.7  85.4    -2.4    442  2.2
 10250   12.3  54.1   080   16    8   7.6   4.2   29.5  85.0    -2.5    416  2.1
 10000   13.1  55.6   075   17    9   9.7   5.3   29.4  84.9    -2.5    385  2.0
  9750   13.8  56.8   070   19   10  10.3   5.6   29.4  85.0    -2.5    355  1.8
  9500   14.6  58.3   070   20   10   8.8   4.8   29.4  85.0    -2.4    326  1.7
  9250   15.1  59.2   065   21   11   6.6   3.6   29.3  84.7    -2.6    302  1.5
  9000   15.6  60.1   065   23   12   6.4   3.5   29.0  84.2    -2.9    281  1.4
  8750   16.1  61.0   065   22   11   6.4   3.5   28.7  83.7    -3.2    259  1.3
  8500   16.5  61.7   065   21   11   6.4   3.5   28.5  83.3    -3.4    238  1.2
  8250   17.0  62.6   060   19   10   6.4   3.5   28.2  82.8    -3.7    217  1.1
  8000   17.5  63.5   060   18    9   6.4   3.5   28.0  82.4    -4.0    196  1.0
  7750   17.9  64.2   055   17    9   6.4   3.5   27.7  81.9    -4.3    174  0.9
  7500   18.4  65.1   050   16    8   6.4   3.5   27.5  81.4    -4.5    153  0.8
  7250   18.8  65.8   045   15    8   6.5   3.6   27.2  81.0    -4.8    132  0.7
  7000   19.3  66.7   040   14    7   6.3   3.4   27.0  80.5    -5.1    110  0.6
  6750   19.8  67.6   045   14    7   7.2   4.0   26.7  80.1    -5.4     89  0.5
  6500   20.4  68.7   045   13    7   9.4   5.2   26.6  79.9    -5.5     63  0.3
  6250   21.2  70.2   050   13    6  11.1   6.1   26.6  80.0    -5.5     33  0.2
  6000   21.9  71.4   055   12    6   7.9   4.4   26.7  80.0    -5.4      2  0.0
  5750   22.0  71.6   060   10    5  -7.5  -4.1   26.1  78.9    -6.1      M    M
  5500   21.0  69.8   065    7    4  -5.6  -3.1   24.5  76.1    -7.8     14  0.1
  5250   21.3  70.3   080    5    3  10.8   5.9   24.1  75.4    -8.3      M    M
  5000   21.6  70.9   110    3    2 -11.4  -6.3   23.7  74.7    -8.8      M    M

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

           09/20/2014 at 0900 MDT          |       09/20/2014 at 1200 MDT
                                           |
K index... +20.3  LI... -0.3               | K index... +18.4  LI... -0.5
CAPE... +80.2  CIN... -122.8               | CAPE... +86.9  CIN... -130.1
                                           |
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 -66.8 -88.2  270  39 20   2.5   1.4 | -67.0 -88.6  270  37 19   2.5   1.4
 45000 -60.9 -77.6  260  59 30   6.5   3.6 | -61.0 -77.8  265  58 30   6.5   3.6
 40000 -51.1 -60.0  265  66 34   7.0   3.8 | -51.1 -60.0  260  63 32   6.7   3.7
 38000 -46.8 -52.2  265  62 32   7.0   3.8 | -47.1 -52.8  260  59 31   6.7   3.7
 36000 -42.6 -44.7  265  59 30   7.1   3.9 | -43.0 -45.4  260  56 29   6.8   3.7
 34000 -39.0 -38.2  265  44 23   6.0   3.3 | -39.1 -38.4  260  43 22   6.5   3.6
 32000 -35.4 -31.7  270  28 14   6.0   3.3 | -35.1 -31.2  265  29 15   6.5   3.6
 30000 -30.7 -23.3  270  18  9   7.1   3.9 | -30.2 -22.4  255  19 10   7.4   4.1
 29000 -28.6 -19.5  270  14  7   7.1   3.9 | -28.0 -18.4  250  16  8   7.4   4.1
 28000 -26.5 -15.7  270  11  6   6.8   3.7 | -25.8 -14.4  240  13  7   6.5   3.5
 27000 -24.5 -12.1  265   9  5   6.8   3.7 | -23.9 -11.0  235  11  6   6.5   3.6
 26000 -22.5  -8.5  260   7  4   6.9   3.8 | -21.9  -7.4  230  10  5   6.6   3.6
 25000 -20.4  -4.7  245   5  3   7.1   3.9 | -20.0  -4.0  220   9  4   6.9   3.8
 24000 -18.3  -0.9  250   5  2   7.3   4.0 | -17.9  -0.2  215   7  4   7.1   3.9
 23000 -16.1   3.0  255   4  2   7.3   4.0 | -15.7   3.7  210   6  3   7.1   3.9
 22000 -13.9   7.0  260   4  2   7.4   4.1 | -13.6   7.5  205   5  3   7.3   4.0
 21000 -11.6  11.1  245   3  1   7.6   4.2 | -11.4  11.5  195   5  3   7.4   4.1
 20000  -9.4  15.1  205   2  1   7.6   4.2 |  -9.2  15.4  185   6  3   7.5   4.1
 19500  -8.3  17.1  175   2  1   7.6   4.2 |  -8.0  17.6  180   6  3   7.5   4.1
 19000  -7.2  19.0  160   2  1   7.5   4.1 |  -6.9  19.6  175   6  3   7.7   4.2
 18500  -6.1  21.0  150   3  1   7.5   4.1 |  -5.8  21.6  175   6  3   7.7   4.2
 18000  -5.0  23.0  145   3  2   7.4   4.1 |  -4.7  23.5  175   6  3   7.4   4.1
 17500  -3.9  25.0  140   3  1   7.4   4.0 |  -3.6  25.5  175   6  3   7.4   4.0
 17000  -2.8  27.0  130   2  1   7.4   4.1 |  -2.6  27.3  170   6  3   7.4   4.1
 16500  -1.7  28.9  120   2  1   7.9   4.4 |  -1.5  29.3  165   5  3   7.5   4.1
 16000  -0.5  31.1  100   2  1   7.9   4.3 |  -0.4  31.3  165   5  2   7.5   4.1
 15500   0.6  33.1  080   1  1   7.4   4.0 |   0.7  33.3  160   4  2   7.9   4.3
 15000   1.6  34.9  055   2  1   7.3   4.0 |   1.9  35.4  155   4  2   8.0   4.4
 14500   2.7  36.9  040   2  1   7.5   4.1 |   3.6  38.5  145   3  1   7.7   4.2
 14000   4.3  39.7  025   2  1   7.7   4.2 |   4.7  40.5  130   2  1   7.7   4.2
 13500   5.4  41.7  015   3  1   7.7   4.2 |   5.8  42.4  110   2  1   7.9   4.3
 13000   6.5  43.7  015   3  2   7.7   4.2 |   7.0  44.6  090   2  1   8.0   4.4
 12500   7.6  45.7  010   4  2   7.9   4.3 |   8.2  46.8  070   2  1   8.0   4.4
 12000   8.8  47.8  020   4  2   8.0   4.4 |   9.3  48.7  070   2  1   8.1   4.4
 11500   9.9  49.8  025   4  2   8.3   4.5 |  10.5  50.9  070   3  1   8.3   4.6
 11000  11.2  52.2  045   4  2   8.2   4.5 |  11.8  53.2  065   4  2   8.4   4.6
 10500  12.4  54.3  055   5  3   4.3   2.4 |  12.9  55.2  065   4  2   3.9   2.1
 10250  12.6  54.7  060   6  3   5.7   3.2 |  13.1  55.6  060   5  3   6.0   3.3
 10000  13.3  55.9  060   7  3  11.7   6.4 |  13.9  57.0  060   6  3  11.5   6.3
  9750  14.1  57.4  065   7  4  10.6   5.8 |  14.6  58.3  060   6  3  10.2   5.6
  9500  14.8  58.6  065   8  4   8.1   4.4 |  15.3  59.5  060   7  3   7.6   4.2
  9250  15.2  59.4  065   9  4   6.2   3.4 |  15.7  60.3  055   7  4   6.5   3.6
  9000  15.8  60.4  065   9  5   8.4   4.6 |  16.3  61.3  055   8  4   9.0   5.0
  8750  16.4  61.5  065  10  5   8.5   4.7 |  16.9  62.4  055   9  5   8.9   4.9
  8500  16.9  62.4  065  10  5   5.8   3.2 |  17.5  63.5  050   9  5   7.4   4.1
  8250  17.2  63.0  065  11  5   4.4   2.4 |  18.0  64.4  050   9  5   6.7   3.7
  8000  17.5  63.5  065  11  6   3.4   1.9 |  18.4  65.1  050   9  5   6.0   3.3
  7750  17.6  63.7  060  11  6   1.2   0.6 |  18.8  65.8  045   9  5   5.6   3.1
  7500  17.7  63.9  060  10  5   0.0   0.0 |  19.2  66.6  045   8  4   6.3   3.5
  7250  17.7  63.9  065  10  5  -0.6  -0.3 |  19.7  67.5  040   8  4   6.4   3.5
  7000  17.6  63.7  065   9  5  -0.6  -0.3 |  20.1  68.2  040   7  3   6.4   3.5
  6750  17.6  63.7  065   8  4  -0.5  -0.3 |  20.6  69.1  035   6  3   8.9   4.9
  6500  17.6  63.7  070   8  4  -0.1  -0.1 |  21.4  70.5  035   6  3  10.8   5.9
  6250  17.6  63.7  070   7  4  -0.1  -0.1 |  22.2  72.0  035   5  3  10.5   5.8
  6000  17.6  63.7  075   7  4  -0.3  -0.2 |  23.0  73.4  035   5  3  10.0   5.5
  5750  17.6  63.7  080   6  3   2.8   1.5 |  23.7  74.7  030   5  2  11.7   6.4
  5500  18.0  64.4  080   5  3   5.8   3.2 |  24.7  76.5  030   5  2  14.0   7.7
  5250  18.3  64.9  080   5  2   3.5   1.9 |  25.7  78.3  030   5  2  12.2   6.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/20/2014 at 1500 MDT          |       09/20/2014 at 1800 MDT
                                           |
K index... +15.4  LI... +0.1               | K index... +20.6  LI... -0.0
CAPE... +34.6  CIN... -90.2                | CAPE... +0.5  CIN... -27.5
                                           |
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 -67.0 -88.6  260  40 20   2.3   1.2 | -66.8 -88.2  260  40 21   2.5   1.4
 45000 -61.2 -78.2  260  58 30   6.6   3.6 | -61.0 -77.8  260  55 28   6.5   3.5
 40000 -51.3 -60.3  260  63 32   6.7   3.7 | -51.2 -60.2  255  62 32   6.7   3.7
 38000 -47.3 -53.1  260  59 30   6.7   3.7 | -47.2 -53.0  255  60 31   6.7   3.7
 36000 -43.2 -45.8  255  55 29   6.8   3.7 | -43.2 -45.8  255  58 30   6.6   3.6
 34000 -39.2 -38.6  255  43 22   6.7   3.7 | -38.9 -38.0  255  49 25   7.3   4.0
 32000 -34.7 -30.5  255  27 14   6.9   3.8 | -33.9 -29.0  255  37 19   7.5   4.1
 30000 -30.2 -22.4  245  22 11   7.5   4.1 | -29.7 -21.5  245  28 14   7.0   3.8
 29000 -28.0 -18.4  240  19 10   7.5   4.1 | -27.6 -17.7  235  24 12   7.0   3.8
 28000 -25.7 -14.3  230  18  9   6.9   3.8 | -25.5 -13.9  225  20 11   6.7   3.7
 27000 -23.7 -10.7  230  16  8   7.0   3.8 | -23.5 -10.3  225  20 10   6.7   3.7
 26000 -21.6  -6.9  225  15  8   7.0   3.8 | -21.5  -6.7  225  19 10   6.7   3.7
 25000 -19.5  -3.1  225  13  7   7.0   3.9 | -19.5  -3.1  220  19 10   7.1   3.9
 24000 -17.4   0.7  215  12  6   7.0   3.9 | -17.2   1.0  220  16  8   7.7   4.2
 23000 -15.3   4.5  205  10  5   7.0   3.9 | -14.9   5.2  215  13  7   7.7   4.2
 22000 -13.2   8.2  195   9  5   7.4   4.0 | -12.6   9.3  205  10  5   7.1   3.9
 21000 -10.9  12.4  190   9  5   7.6   4.2 | -10.8  12.6  200  10  5   6.5   3.5
 20000  -8.7  16.3  190   9  5   7.6   4.2 |  -8.9  16.0  195  10  5   6.6   3.6
 19500  -7.5  18.5  190   9  5   7.6   4.2 |  -8.0  17.6  195  10  5   6.6   3.6
 19000  -6.4  20.5  190   9  5   7.6   4.2 |  -7.0  19.4  195   9  5   7.8   4.3
 18500  -5.3  22.5  195   8  4   7.6   4.2 |  -5.8  21.6  195   9  5   7.7   4.2
 18000  -4.1  24.6  195   8  4   7.6   4.2 |  -4.7  23.5  195   9  5   8.0   4.4
 17500  -3.0  26.6  195   8  4   7.7   4.2 |  -3.6  25.5  195   9  4   8.2   4.5
 17000  -2.0  28.4  195   7  4   7.8   4.3 |  -2.4  27.7  195   8  4   8.3   4.5
 16500  -0.8  30.6  190   7  4   7.7   4.2 |  -1.2  29.8  190   8  4   8.5   4.7
 16000   0.3  32.5  180   6  3   7.7   4.2 |   0.1  32.2  185   7  3   8.5   4.7
 15500   1.4  34.5  170   6  3   8.0   4.4 |   2.0  35.6  175   6  3   8.3   4.6
 15000   3.2  37.8  160   6  3   8.1   4.4 |   3.3  37.9  165   5  3   8.4   4.6
 14500   4.4  39.9  150   5  2   8.2   4.5 |   4.6  40.3  150   4  2   8.4   4.6
 14000   5.6  42.1  140   4  2   8.2   4.5 |   5.8  42.4  120   3  2   8.4   4.6
 13500   6.8  44.2  120   3  1   8.3   4.6 |   7.0  44.6  090   4  2   8.4   4.6
 13000   8.0  46.4  090   2  1   8.4   4.6 |   8.3  46.9  065   5  2   8.4   4.6
 12500   9.2  48.6  055   3  1   8.2   4.5 |   9.5  49.1  055   6  3   8.5   4.6
 12000  10.4  50.7  040   4  2   8.1   4.4 |  10.7  51.3  050   8  4   8.5   4.7
 11500  11.6  52.9  030   5  2   8.1   4.5 |  12.0  53.6  050   9  5   8.8   4.8
 11000  12.8  55.0  030   5  3   8.0   4.4 |  13.3  55.9  050  10  5   8.9   4.9
 10500  14.0  57.2  025   6  3   5.3   2.9 |  14.7  58.5  050  11  6   6.3   3.5
 10250  14.3  57.7  025   6  3   6.8   3.7 |  15.1  59.2  050  11  6   7.4   4.1
 10000  15.0  59.0  025   7  3  10.9   6.0 |  15.9  60.6  050  11  6  11.5   6.3
  9750  15.8  60.4  025   7  4  10.3   5.7 |  16.7  62.1  050  11  6  11.0   6.0
  9500  16.5  61.7  025   7  4   7.9   4.3 |  17.5  63.5  050  11  6   8.9   4.9
  9250  16.9  62.4  025   7  4   7.2   4.0 |  18.0  64.4  050  11  6   7.5   4.1
  9000  17.6  63.7  025   7  4   9.8   5.4 |  18.7  65.7  050  11  6   9.2   5.0
  8750  18.2  64.8  025   7  4   9.5   5.2 |  19.3  66.7  050  10  5   8.8   4.8
  8500  18.9  66.0  025   7  4   9.3   5.1 |  20.0  68.0  050  10  5   9.1   5.0
  8250  19.6  67.3  025   7  3   9.1   5.0 |  20.7  69.3  050   9  5   9.3   5.1
  8000  20.3  68.5  025   7  3   9.7   5.3 |  21.3  70.3  050   9  4   8.6   4.7
  7750  21.0  69.8  025   6  3  10.0   5.5 |  21.9  71.4  055   8  4   8.2   4.5
  7500  21.7  71.1  025   6  3  10.0   5.5 |  22.6  72.7  055   8  4   9.0   4.9
  7250  22.5  72.5  025   6  3  10.1   5.5 |  23.2  73.8  055   7  4   9.4   5.2
  7000  23.2  73.8  025   6  3  10.0   5.5 |  23.9  75.0  055   7  4   9.4   5.1
  6750  24.0  75.2  025   6  3  10.3   5.7 |  24.6  76.3  060   7  3   9.8   5.4
  6500  24.7  76.5  025   6  3  10.6   5.8 |  25.4  77.7  060   6  3  10.1   5.6
  6250  25.5  77.9  025   5  3  11.0   6.0 |  26.1  79.0  060   6  3  10.3   5.7
  6000  26.3  79.3  025   5  3   9.6   5.3 |  26.9  80.4  065   6  3  10.1   5.5
  5750  27.0  80.6  025   5  3  11.2   6.2 |  27.6  81.7  065   5  3   8.0   4.4
  5500  28.0  82.4  020   5  3  14.5   8.0 |  28.1  82.6  065   5  3   6.5   3.5
  5250  29.0  84.2  020   5  3  11.9   6.5 |  28.6  83.5  060   5  3   7.6   4.2
  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 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  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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