Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 261243
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0643 MDT Sunday, July 26, 2015

This forecast is for Sunday, July 26, 2015:

If the trigger temperature of 87.7 F/31.0 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 561 ft/min (2.8 m/s)
   Maximum height of thermals.................. 11501 ft MSL (6662 ft AGL)

Forecast maximum temperature................... 89.0 F/32.1 C
Time of trigger temperature.................... 1415 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................. 7362 ft MSL (2523 ft AGL)
Thermal soaring outlook for Monday 07/27....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:09:15 / 20:32:18 MDT
Total possible sunshine........... 14 hr 23 min 3 sec (863 min 3 sec)
Altitude of sun at 13:20:36 MDT... 70.23 degrees

Upper air data from rawinsonde observation taken on 07/26/2015 at 0600 MDT

Freezing level.................. 15574 ft MSL (10735 ft AGL)
Convective condensation level... 18544 ft MSL (13705 ft AGL)
Lifted condensation level....... 16811 ft MSL (11971 ft AGL)
Lifted index.................... +1.8
K index......................... +16.9

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  -70.1 -94.2   230   43   22   4.3   2.4   76.3 169.4    26.0      M    M
 45000  -61.9 -79.4   235   55   28   5.7   3.1   65.5 149.9    21.1      M    M
 40000  -50.9 -59.6   225   56   29   6.0   3.3   60.0 139.9    18.9      M    M
 38000  -47.2 -53.0   225   55   28   6.1   3.4   56.6 133.9    17.1      M    M
 36000  -41.8 -43.2   225   54   28   8.9   4.9   55.0 131.0    16.4      M    M
 34000  -36.8 -34.2   225   51   26   8.4   4.6   53.7 128.7    16.0      M    M
 32000  -31.6 -24.9   225   47   24   8.9   4.9   53.0 127.3    15.8      M    M
 30000  -27.0 -16.6   225   47   24   5.3   2.9   51.3 124.4    14.9      M    M
 29000  -25.6 -14.1   225   44   22   1.6   0.9   49.3 120.7    13.5      M    M
 28000  -24.9 -12.8   225   40   21   6.7   3.7   46.4 115.6    11.5      M    M
 27000  -24.0 -11.2   225   37   19   4.3   2.4   43.9 111.1     9.6      M    M
 26000  -21.1  -6.0   220   33   17   9.5   5.2   43.9 111.0     9.6      M    M
 25000  -18.3  -0.9   220   30   16   9.1   5.0   43.7 110.7     9.6      M    M
 24000  -15.8   3.6   220   29   15   8.1   4.4   43.2 109.7     9.3      M    M
 23000  -14.1   6.6   220   28   14  -0.8  -0.5   41.7 107.0     8.2      M    M
 22000  -13.3   8.1   220   27   14   9.1   5.0   39.2 102.5     6.1      M    M
 21000  -10.8  12.6   220   25   13   9.0   5.0   38.8 101.8     5.7      M    M
 20000   -8.1  17.4   220   24   12   6.4   3.5   38.2 100.8     5.6      M    M
 19500   -6.6  20.1   240   18    9   6.8   3.7   37.4  99.3     4.9      M    M
 19000   -5.5  22.1   250   18    9   7.2   4.0   36.9  98.5     4.5      M    M
 18500   -4.5  23.9   250   16    8   7.2   3.9   36.5  97.7     4.2      M    M
 18000   -3.4  25.9   250   14    7   6.4   3.5   36.1  96.9     3.8      M    M
 17500   -2.8  27.0   250   12    6  -2.9  -1.6   35.2  95.3     3.0      M    M
 17000   -3.5  25.7   250   10    5   4.2   2.3   32.9  91.3     0.8      M    M
 16500   -2.5  27.5   255    8    4   9.6   5.3   32.6  90.6     0.3      M    M
 16000   -1.1  30.0   255    6    3   9.7   5.3   32.6  90.6     0.3      M    M
 15500    0.4  32.7   245    5    3   9.7   5.3   32.5  90.6     0.3      M    M
 15000    1.9  35.4   235    5    3   9.7   5.3   32.5  90.5     0.3      M    M
 14500    3.3  37.9   225    5    3   9.7   5.3   32.5  90.6     0.3      M    M
 14000    4.8  40.6   215    5    3   9.7   5.3   32.6  90.6     0.3      M    M
 13500    6.2  43.2   215    4    2   9.7   5.3   32.5  90.5     0.3      M    M
 13000    7.7  45.9   215    3    2   9.7   5.3   32.5  90.4     0.3      M    M
 12500    9.1  48.4   210    3    1   9.4   5.2   32.4  90.4     0.3      M    M
 12000   10.4  50.7   210    2    1   9.4   5.2   32.4  90.3     0.1      M    M
 11500   11.8  53.2   210    3    2   9.4   5.2   32.3  90.2    -0.0    560  2.8
 11000   13.1  55.6   210    4    2   9.5   5.2   32.3  90.1    -0.1    505  2.6
 10500   14.5  58.1   210    6    3   9.5   5.2   32.2  90.0    -0.2    450  2.3
 10250   15.1  59.2   210    6    3   9.1   5.0   32.2  90.0    -0.3    423  2.1
 10000   15.8  60.4   210    5    3   9.0   4.9   32.2  89.9    -0.4    395  2.0
  9750   16.5  61.7   205    5    2   9.0   5.0   32.1  89.8    -0.4    368  1.9
  9500   17.1  62.8   205    4    2   9.0   5.0   32.0  89.7    -0.5    341  1.7
  9250   17.8  64.0   200    4    2   9.0   5.0   32.0  89.6    -0.6    313  1.6
  9000   18.5  65.3   195    3    2   9.0   5.0   32.0  89.5    -0.6    286  1.5
  8750   19.1  66.4   180    4    2   9.0   4.9   31.9  89.4    -0.7    259  1.3
  8500   19.8  67.6   175    6    3   9.3   5.1   31.8  89.3    -0.8    232  1.2
  8250   20.4  68.7   170    7    4   8.1   4.5   31.8  89.2    -0.8    204  1.0
  8000   20.9  69.6   165    9    4   5.3   2.9   31.5  88.8    -1.1    182  0.9
  7750   21.2  70.2   160    9    4   2.2   1.2   31.1  87.9    -1.5    165  0.8
  7500   21.3  70.3   155    8    4  -2.1  -1.1   30.3  86.6    -2.2    158  0.8
  7250   21.0  69.8   150    8    4  -3.4  -1.9   29.3  84.8    -3.2    159  0.8
  7000   20.7  69.3   145    7    4  -4.5  -2.5   28.3  83.0    -4.3    160  0.8
  6750   20.4  68.7   140    6    3   1.2   0.6   27.3  81.2    -5.3    161  0.8
  6500   20.8  69.4   130    6    3   7.1   3.9   27.0  80.6    -5.6    141  0.7
  6250   21.3  70.3   115    5    3   6.0   3.3   26.7  80.1    -5.9    120  0.6
  6000   21.7  71.1   100    5    3   5.4   2.9   26.5  79.6    -6.2     99  0.5
  5750   22.0  71.6   095    5    3   1.4   0.7   26.0  78.8    -6.7     84  0.4
  5500   22.0  71.6   095    5    3  -0.5  -0.3   25.2  77.4    -7.4     76  0.4
  5250   21.7  71.1   100    5    3 -10.7  -5.9   24.2  75.6    -8.4     77  0.4
  5000   20.2  68.4   100    5    3 -29.5 -16.2   21.9  71.5   -10.8    117  0.6

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

           07/26/2015 at 0900 MDT          |       07/26/2015 at 1200 MDT
                                           |
K index... +22.0  LI... +273.6             | K index... +17.9  LI... +272.6
CAPE... 0.0  CIN... -7.1                   | CAPE... +20.8  CIN... -94.6
                                           |
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 -66.3 -87.3  245  41 21   1.8   1.0 | -66.1 -87.0  240  41 21   1.8   1.0
 45000 -61.3 -78.3  240  54 28   6.4   3.5 | -61.2 -78.2  235  55 28   6.2   3.4
 40000 -50.9 -59.6  235  60 31   7.5   4.1 | -51.1 -60.0  230  62 32   7.4   4.1
 38000 -46.5 -51.7  230  57 30   7.4   4.1 | -46.7 -52.1  230  61 31   7.4   4.1
 36000 -42.0 -43.6  230  55 28   7.7   4.2 | -42.2 -44.0  230  59 30   7.6   4.2
 34000 -37.1 -34.8  230  53 27   8.2   4.5 | -37.4 -35.3  230  57 29   8.1   4.4
 32000 -32.2 -26.0  230  51 26   8.3   4.6 | -32.6 -26.7  230  54 28   8.2   4.5
 30000 -28.3 -18.9  230  46 23   6.3   3.4 | -28.5 -19.3  230  48 25   6.6   3.6
 29000 -26.5 -15.7  230  43 22   6.3   3.4 | -26.5 -15.7  230  45 23   6.6   3.6
 28000 -24.6 -12.3  230  39 20   5.9   3.2 | -24.6 -12.3  230  42 22   5.9   3.2
 27000 -22.9  -9.2  230  37 19   5.7   3.1 | -22.6  -8.7  230  38 19   5.5   3.0
 26000 -20.8  -5.4  230  33 17   5.7   3.1 | -21.0  -5.8  230  35 18   5.6   3.1
 25000 -19.2  -2.6  230  30 15   6.4   3.5 | -19.3  -2.7  230  31 16   6.3   3.5
 24000 -17.1   1.2  230  27 14   7.2   3.9 | -17.3   0.9  230  29 15   6.9   3.8
 23000 -15.0   5.0  230  25 13   7.3   4.0 | -15.3   4.5  235  28 14   7.0   3.8
 22000 -13.0   8.6  230  22 11   6.5   3.6 | -13.2   8.2  235  26 13   6.9   3.8
 21000 -11.1  12.0  230  21 11   6.0   3.3 | -11.2  11.8  235  23 12   6.9   3.8
 20000  -9.1  15.6  235  19 10   6.1   3.4 |  -9.2  15.4  240  21 11   7.0   3.8
 19500  -8.2  17.2  235  18 10   6.2   3.4 |  -8.2  17.2  240  20 10   7.0   3.8
 19000  -7.2  19.0  235  18  9   7.3   4.0 |  -7.2  19.0  245  19 10   7.1   3.9
 18500  -6.1  21.0  240  17  9   7.3   4.0 |  -6.1  21.0  245  18  9   7.2   3.9
 18000  -5.1  22.8  240  17  9   7.4   4.0 |  -5.1  22.8  250  17  9   7.2   4.0
 17500  -4.0  24.8  240  16  8   7.5   4.1 |  -4.0  24.8  250  17  9   7.2   4.0
 17000  -3.0  26.6  240  15  8   7.6   4.2 |  -3.0  26.6  250  16  8   7.3   4.0
 16500  -1.8  28.8  240  14  7   8.5   4.7 |  -1.7  28.9  250  15  8   8.6   4.7
 16000  -0.7  30.7  235  13  7   8.6   4.7 |  -0.4  31.3  245  14  7   8.6   4.7
 15500   0.5  32.9  235  11  6   8.9   4.9 |   0.9  33.6  245  13  7   8.7   4.8
 15000   1.9  35.4  235  10  5   8.9   4.9 |   2.2  36.0  240  13  6   8.8   4.8
 14500   3.2  37.8  230   9  5   8.8   4.8 |   3.5  38.3  240  12  6   8.8   4.8
 14000   4.5  40.1  230   8  4   8.6   4.7 |   4.8  40.6  235  11  6   8.9   4.9
 13500   5.8  42.4  225   7  4   8.7   4.8 |   6.1  43.0  230  10  5   8.8   4.9
 13000   7.7  45.9  220   6  3   9.0   4.9 |   8.0  46.4  225   9  4   8.7   4.8
 12500   9.1  48.4  220   6  3   8.8   4.8 |   9.3  48.7  220   8  4   8.9   4.9
 12000  10.3  50.5  220   5  3   8.7   4.8 |  10.6  51.1  215   7  4   8.9   4.9
 11500  11.6  52.9  220   5  2   8.6   4.7 |  11.9  53.4  210   7  3   8.9   4.9
 11000  12.8  55.0  215   4  2   8.3   4.5 |  13.2  55.8  210   6  3   8.6   4.7
 10500  14.1  57.4  215   4  2   5.0   2.8 |  14.5  58.1  205   6  3   5.0   2.7
 10250  14.3  57.7  215   4  2   5.8   3.2 |  14.7  58.5  205   6  3   5.9   3.3
 10000  15.0  59.0  210   4  2  10.5   5.8 |  15.5  59.9  205   5  3  11.3   6.2
  9750  15.7  60.3  205   4  2   9.8   5.4 |  16.2  61.2  200   5  3  10.4   5.7
  9500  16.4  61.5  205   4  2   7.9   4.3 |  17.0  62.6  200   5  3   8.2   4.5
  9250  16.9  62.4  195   4  2   6.7   3.6 |  17.5  63.5  200   5  3   7.0   3.8
  9000  17.5  63.5  190   4  2   8.4   4.6 |  18.1  64.6  195   5  2   8.8   4.8
  8750  18.1  64.6  185   5  2   8.3   4.6 |  18.7  65.7  195   5  2   8.5   4.6
  8500  18.7  65.7  180   5  3   7.9   4.3 |  19.3  66.7  195   5  2   8.1   4.5
  8250  19.3  66.7  180   6  3   7.5   4.1 |  19.9  67.8  195   5  2   7.8   4.3
  8000  19.8  67.6  175   6  3   6.2   3.4 |  20.5  68.9  190   5  2   7.5   4.1
  7750  20.2  68.4  170   7  4   4.8   2.7 |  21.0  69.8  190   5  2   7.5   4.1
  7500  20.6  69.1  170   8  4   3.6   2.0 |  21.6  70.9  190   5  2   8.3   4.5
  7250  20.8  69.4  165   8  4   2.9   1.6 |  22.2  72.0  190   5  2   8.5   4.7
  7000  21.0  69.8  160   9  5   2.5   1.4 |  22.8  73.0  190   5  3   9.0   4.9
  6750  21.1  70.0  160   9  5   0.9   0.5 |  23.4  74.1  190   5  2  10.3   5.7
  6500  21.1  70.0  155   8  4  -0.3  -0.2 |  24.2  75.6  190   5  2  10.9   6.0
  6250  21.0  69.8  150   7  4   0.5   0.3 |  25.0  77.0  190   5  2  11.4   6.3
  6000  21.0  69.8  145   6  3  -2.6  -1.4 |  25.8  78.4  195   5  2   9.6   5.3
  5750  20.8  69.4  130   5  2   3.2   1.8 |  26.5  79.7  195   4  2  11.6   6.4
  5500  21.4  70.5  130   4  2  12.4   6.8 |  27.6  81.7  195   4  2  15.5   8.5
  5250  22.1  71.8  125   4  2   5.2   2.9 |  28.6  83.5  195   4  2  12.4   6.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/26/2015 at 1500 MDT          |       07/26/2015 at 1800 MDT
                                           |
K index... +24.0  LI... +273.3             | K index... +28.2  LI... +273.1
CAPE... 0.0  CIN... -1.1                   | CAPE... +13.2  CIN... -43.8
                                           |
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 -65.9 -86.6  240  39 20   2.1   1.1 | -66.0 -86.8  235  38 20   1.6   0.9
 45000 -60.7 -77.3  235  56 29   6.3   3.5 | -61.0 -77.8  235  56 29   7.0   3.8
 40000 -50.6 -59.1  230  64 33   7.0   3.8 | -50.0 -58.0  230  59 31   6.7   3.7
 38000 -46.4 -51.5  230  63 32   7.0   3.8 | -46.0 -50.8  230  60 31   6.7   3.7
 36000 -42.2 -44.0  230  61 32   7.3   4.0 | -42.0 -43.6  225  60 31   7.1   3.9
 34000 -37.5 -35.5  230  58 30   7.8   4.3 | -37.3 -35.1  225  57 29   7.9   4.3
 32000 -32.8 -27.0  225  55 28   7.8   4.3 | -32.6 -26.7  225  55 28   7.9   4.3
 30000 -28.5 -19.3  225  50 26   7.2   3.9 | -28.1 -18.6  225  52 27   7.4   4.0
 29000 -26.4 -15.5  225  48 25   7.2   3.9 | -25.9 -14.6  225  51 26   7.4   4.0
 28000 -23.8 -10.8  225  45 23   5.9   3.3 | -23.3  -9.9  225  49 25   6.1   3.3
 27000 -22.0  -7.6  225  42 22   6.1   3.3 | -21.5  -6.7  225  46 24   6.3   3.4
 26000 -20.2  -4.4  225  40 20   6.1   3.4 | -19.7  -3.5  225  44 23   6.4   3.5
 25000 -18.4  -1.1  230  37 19   6.7   3.7 | -17.8  -0.0  225  42 21   6.2   3.4
 24000 -16.4   2.5  230  34 18   7.1   3.9 | -16.1   3.0  230  35 18   6.0   3.3
 23000 -14.3   6.3  235  31 16   7.1   3.9 | -14.3   6.3  235  29 15   6.1   3.3
 22000 -12.2  10.0  235  29 15   6.8   3.7 | -12.6   9.3  240  23 12   6.9   3.8
 21000 -10.3  13.5  240  25 13   6.5   3.6 | -10.4  13.3  240  19 10   7.5   4.1
 20000  -8.4  16.9  240  22 11   6.6   3.6 |  -8.3  17.1  240  14  7   7.5   4.1
 19500  -7.4  18.7  245  20 10   6.6   3.6 |  -7.2  19.0  240  12  6   7.5   4.1
 19000  -6.4  20.5  245  18  9   6.7   3.7 |  -6.1  21.0  240  11  5   7.7   4.2
 18500  -5.4  22.3  245  17  9   6.7   3.7 |  -5.0  23.0  240  10  5   7.7   4.2
 18000  -4.5  23.9  245  16  8   7.0   3.9 |  -3.8  25.2  240   9  5   6.7   3.7
 17500  -3.4  25.9  245  16  8   7.2   4.0 |  -3.0  26.6  235   8  4   6.0   3.3
 17000  -2.4  27.7  245  16  8   7.3   4.0 |  -2.1  28.2  225   7  4   6.0   3.3
 16500  -1.3  29.7  240  15  8   8.1   4.5 |  -1.1  30.0  220   7  4   7.4   4.1
 16000  -0.1  31.8  235  14  7   8.1   4.4 |  -0.0  32.0  215   7  4   7.2   4.0
 15500   1.1  34.0  235  13  7   8.7   4.8 |   1.1  34.0  210   7  4   8.4   4.6
 15000   2.4  36.3  230  12  6   8.8   4.8 |   2.4  36.3  205   7  4   8.7   4.8
 14500   3.7  38.7  230  12  6   9.2   5.0 |   3.6  38.5  205   7  4   9.0   4.9
 14000   5.1  41.2  225  11  6   9.6   5.3 |   5.0  41.0  205   8  4   9.4   5.2
 13500   7.3  45.1  225   9  5   9.4   5.1 |   7.1  44.8  205   8  4   9.2   5.1
 13000   8.6  47.5  225   9  4   9.3   5.1 |   8.5  47.3  205   8  4   9.2   5.0
 12500  10.0  50.0  225   8  4   9.0   4.9 |   9.9  49.8  200   8  4   9.3   5.1
 12000  11.3  52.3  225   7  4   8.8   4.8 |  11.3  52.3  205   8  4   9.4   5.2
 11500  12.6  54.7  225   6  3   8.5   4.7 |  12.7  54.9  205   8  4   8.8   4.8
 11000  13.9  57.0  230   5  3   8.1   4.5 |  13.9  57.0  205   8  4   8.2   4.5
 10500  15.1  59.2  230   4  2   5.4   2.9 |  15.1  59.2  205   8  4  11.5   6.3
 10250  15.4  59.7  230   4  2   6.2   3.4 |  16.1  61.0  205   7  4  12.0   6.6
 10000  16.1  61.0  235   4  2  10.2   5.6 |  16.8  62.2  205   7  4   7.7   4.2
  9750  16.8  62.2  235   4  2   9.9   5.4 |  17.4  63.3  205   7  4   9.2   5.1
  9500  17.5  63.5  235   3  2   7.1   3.9 |  18.1  64.6  205   7  3   7.4   4.1
  9250  18.0  64.4  240   3  2   6.8   3.8 |  18.6  65.5  205   7  3   7.5   4.1
  9000  18.7  65.7  240   3  2   9.9   5.4 |  19.2  66.6  205   6  3   8.9   4.9
  8750  19.3  66.7  245   3  2   9.0   4.9 |  19.9  67.8  205   6  3   8.5   4.7
  8500  20.0  68.0  245   3  1   9.8   5.4 |  20.5  68.9  210   6  3   8.5   4.7
  8250  20.7  69.3  250   3  2  10.4   5.7 |  21.1  70.0  210   6  3   8.3   4.5
  8000  21.5  70.7  250   3  2  10.0   5.5 |  21.8  71.2  210   6  3   8.3   4.5
  7750  22.2  72.0  250   3  2   9.9   5.4 |  22.3  72.1  210   6  3   8.1   4.4
  7500  23.0  73.4  250   3  2  10.0   5.5 |  22.9  73.2  215   6  3   9.2   5.0
  7250  23.7  74.7  250   3  2  10.3   5.6 |  23.7  74.7  215   6  3  10.2   5.6
  7000  24.5  76.1  250   3  2   9.5   5.2 |  24.4  75.9  215   6  3   9.5   5.2
  6750  25.2  77.4  250   3  2   9.4   5.2 |  25.1  77.2  215   6  3   9.4   5.1
  6500  25.9  78.6  250   3  2  10.9   6.0 |  25.9  78.6  215   6  3  10.1   5.6
  6250  26.8  80.2  250   3  2  11.7   6.4 |  26.6  79.9  215   6  3  10.7   5.9
  6000  27.6  81.7  250   4  2  10.0   5.5 |  27.4  81.3  215   6  3   9.8   5.4
  5750  28.3  82.9  250   3  2  11.9   6.5 |  28.1  82.6  215   6  3   9.2   5.0
  5500  29.4  84.9  255   4  2  15.9   8.7 |  28.8  83.8  220   6  3   9.8   5.4
  5250  30.5  86.9  255   4  2  13.4   7.4 |  29.5  85.1  220   5  3   9.9   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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