Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 231224
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0624 MDT Thursday, July 23, 2015

This forecast is for Thursday, July 23, 2015:

If the trigger temperature of 83.0 F/28.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1303 ft/min (6.6 m/s)
   Maximum height of thermals.................. 18594 ft MSL (13755 ft AGL)

Forecast maximum temperature................... 91.0 F/33.2 C
Time of trigger temperature.................... 1200 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................. 10772 ft MSL (5933 ft AGL)
Thermal soaring outlook for Friday 07/24....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:06:44 / 20:34:42 MDT
Total possible sunshine........... 14 hr 27 min 58 sec (867 min 58 sec)
Altitude of sun at 13:20:34 MDT... 70.87 degrees

Upper air data from rawinsonde observation taken on 07/23/2015 at 0600 MDT

Freezing level.................. 15036 ft MSL (10197 ft AGL)
Convective condensation level... 15502 ft MSL (10663 ft AGL)
Lifted condensation level....... 16423 ft MSL (11583 ft AGL)
Lifted index.................... -0.2
K index......................... +23.3

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  -69.1 -92.4   250   32   17  -0.6  -0.3   78.1 172.6    26.4      M    M
 45000  -60.6 -77.1   230   44   23   5.0   2.8   67.6 153.7    21.7      M    M
 40000  -50.2 -58.4   240   53   27   8.7   4.8   61.1 142.0    18.9      M    M
 38000  -46.9 -52.4   245   51   26   7.7   4.2   57.4 135.3    16.8      M    M
 36000  -40.8 -41.4   245   50   26   9.1   5.0   56.7 134.1    16.9      M    M
 34000  -36.4 -33.5   245   47   24   7.8   4.3   54.6 130.2    15.8      M    M
 32000  -31.7 -25.1   250   44   23   8.3   4.5   53.1 127.5    15.0      M    M
 30000  -28.2 -18.8   245   40   21   7.6   4.2   50.0 122.0    13.1      M    M
 29000  -25.8 -14.4   245   39   20   7.9   4.4   49.2 120.5    12.6      M    M
 28000  -23.4 -10.1   250   38   20   7.9   4.3   48.5 119.3    12.2      M    M
 27000  -21.2  -6.2   250   37   19   6.0   3.3   47.6 117.6    11.6      M    M
 26000  -19.4  -2.9   255   37   19   6.0   3.3   46.2 115.1    10.6      M    M
 25000  -18.1  -0.6   255   36   19   4.6   2.5   44.1 111.4     9.1      M    M
 24000  -15.8   3.6   260   37   19   7.9   4.4   43.4 110.1     8.6      M    M
 23000  -14.4   6.1   255   34   18  -1.0  -0.5   41.5 106.8     7.2      M    M
 22000  -14.1   6.6   250   32   17   6.3   3.5   38.3 101.0     4.6      M    M
 21000  -12.3   9.9   240   30   16   6.1   3.3   37.0  98.6     3.5      M    M
 20000  -10.3  13.5   230   29   15   6.6   3.6   35.9  96.6     2.6      M    M
 19500   -9.5  14.9   220   35   18   0.8   0.5   34.3  93.7     1.3      M    M
 19000   -9.0  15.8   210   35   18   6.0   3.3   33.3  91.9     0.3      M    M
 18500   -8.0  17.6   215   35   18   7.8   4.3   32.8  91.1    -0.1   1283  6.5
 18000   -6.8  19.8   215   36   19   7.6   4.2   32.5  90.5    -0.5   1235  6.3
 17500   -5.7  21.7   220   37   19   9.0   4.9   32.2  90.0    -0.8   1186  6.0
 17000   -4.4  24.1   220   37   19   8.9   4.9   32.1  89.7    -1.0   1134  5.8
 16500   -3.2  26.2   215   34   18   8.9   4.9   31.9  89.5    -1.2   1080  5.5
 16000   -1.9  28.6   215   32   16   7.7   4.2   31.8  89.3    -1.4   1027  5.2
 15500   -1.1  30.0   220   30   15   7.8   4.3   31.2  88.2    -2.1    989  5.0
 15000    0.3  32.5   220   28   14   8.9   4.9   31.1  88.0    -2.2    934  4.7
 14500    1.6  34.9   225   26   14   9.1   5.0   31.0  87.8    -2.3    878  4.5
 14000    3.0  37.4   230   25   13   9.2   5.0   30.9  87.6    -2.5    823  4.2
 13500    4.3  39.7   235   23   12   9.2   5.0   30.8  87.4    -2.6    768  3.9
 13000    5.6  42.1   235   22   11   9.2   5.0   30.7  87.2    -2.7    713  3.6
 12500    7.0  44.6   240   20   10   9.5   5.2   30.6  87.1    -2.8    656  3.3
 12000    8.5  47.3   245   19   10   9.5   5.2   30.6  87.1    -2.8    598  3.0
 11500   10.0  50.0   250   18    9   9.5   5.2   30.6  87.0    -2.8    539  2.7
 11000   11.4  52.5   255   18    9   8.9   4.9   30.5  87.0    -2.8    481  2.4
 10500   12.5  54.5   260   17    9   6.5   3.6   30.3  86.6    -3.2    433  2.2
 10250   12.9  55.2   260   17    9   6.6   3.6   30.0  86.0    -3.6    414  2.1
 10000   13.5  56.3   260   18    9   8.8   4.8   29.9  85.8    -3.7    388  2.0
  9750   14.1  57.4   260   18    9   8.2   4.5   29.8  85.6    -3.8    362  1.8
  9500   14.7  58.5   255   19   10   8.4   4.6   29.7  85.4    -3.9    337  1.7
  9250   15.3  59.5   255   19   10   8.3   4.6   29.6  85.2    -4.1    311  1.6
  9000   16.0  60.8   255   20   10   8.3   4.6   29.5  85.0    -4.2    285  1.4
  8750   16.6  61.9   255   18    9   8.3   4.6   29.4  84.8    -4.3    259  1.3
  8500   17.2  63.0   250   17    9   8.3   4.6   29.2  84.6    -4.4    234  1.2
  8250   17.8  64.0   245   15    8   8.3   4.6   29.1  84.4    -4.6    208  1.1
  8000   18.4  65.1   240   13    7   8.3   4.6   29.0  84.3    -4.7    182  0.9
  7750   19.0  66.2   240   12    6   8.3   4.6   28.9  84.0    -4.8    156  0.8
  7500   19.6  67.3   240   10    5   8.4   4.6   28.8  83.8    -5.0    130  0.7
  7250   20.2  68.4   240    8    4   8.2   4.5   28.7  83.6    -5.1    105  0.5
  7000   20.9  69.6   240    6    3   8.8   4.8   28.6  83.4    -5.2     79  0.4
  6750   21.5  70.7   220    5    3   6.7   3.7   28.5  83.2    -5.4     53  0.3
  6500   21.7  71.1   190    6    3   0.1   0.1   28.0  82.4    -5.8     38  0.2
  6250   21.5  70.7   165    7    4  -3.1  -1.7   27.1  80.7    -6.8     36  0.2
  6000   21.5  70.7   155    9    5   3.9   2.1   26.3  79.3    -7.6     30  0.2
  5750   22.0  71.6   150    9    5   8.9   4.9   26.1  79.0    -7.8      7  0.0
  5500   22.6  72.7   145    7    4   6.8   3.7   26.0  78.8    -8.0      M    M
  5250   22.5  72.5   145    6    3 -13.5  -7.4   25.2  77.4    -8.8      M    M
  5000   20.2  68.4   140    4    2 -37.9 -20.8   22.4  72.3   -11.8     38  0.2

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

           07/23/2015 at 0900 MDT          |       07/23/2015 at 1200 MDT
                                           |
K index... +15.8  LI... +273.4             | K index... +17.6  LI... +272.9
CAPE... +0.8  CIN... -2.6                  | CAPE... 0.0  CIN... -0.4
                                           |
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  240  29 15   1.6   0.9 | -66.1 -87.0  235  27 14   0.9   0.5
 45000 -61.1 -78.0  245  44 22   7.4   4.0 | -61.5 -78.7  245  43 22   7.5   4.1
 40000 -49.7 -57.5  250  51 26   6.6   3.6 | -49.9 -57.8  245  51 26   6.6   3.6
 38000 -45.8 -50.4  250  49 25   6.6   3.6 | -45.9 -50.6  245  49 25   6.6   3.6
 36000 -41.8 -43.2  250  46 24   7.0   3.8 | -42.0 -43.6  245  47 24   7.0   3.9
 34000 -37.1 -34.8  250  44 22   7.9   4.3 | -37.3 -35.1  245  46 23   7.9   4.3
 32000 -32.4 -26.3  250  41 21   8.0   4.4 | -32.5 -26.5  245  44 22   8.0   4.4
 30000 -28.3 -18.9  255  38 20   6.7   3.7 | -28.4 -19.1  250  40 21   6.7   3.7
 29000 -26.3 -15.3  255  37 19   6.7   3.7 | -26.4 -15.5  255  38 20   6.7   3.7
 28000 -24.3 -11.7  255  36 18   7.0   3.8 | -23.8 -10.8  255  36 19   7.5   4.1
 27000 -22.1  -7.8  255  36 18   7.2   4.0 | -21.6  -6.9  255  36 19   7.4   4.1
 26000 -19.4  -2.9  250  36 19   7.2   4.0 | -19.4  -2.9  255  36 19   7.4   4.1
 25000 -17.3   0.9  250  36 19   6.6   3.6 | -17.2   1.0  255  36 19   6.9   3.8
 24000 -15.6   3.9  250  35 18   5.5   3.0 | -15.3   4.5  255  34 17   6.3   3.5
 23000 -13.9   7.0  250  33 17   5.5   3.0 | -13.4   7.9  250  32 16   6.3   3.5
 22000 -12.3   9.9  250  31 16   5.2   2.9 | -11.5  11.3  250  29 15   5.6   3.1
 21000 -10.8  12.6  250  30 16   4.9   2.7 | -10.0  14.0  250  28 14   4.9   2.7
 20000  -9.4  15.1  245  29 15   4.9   2.7 |  -8.6  16.5  250  27 14   4.9   2.7
 19500  -8.7  16.3  245  29 15   4.8   2.6 |  -7.8  18.0  250  26 13   4.9   2.7
 19000  -7.9  17.8  245  28 15   5.9   3.2 |  -7.0  19.4  245  26 13   6.4   3.5
 18500  -7.0  19.4  245  28 15   5.8   3.2 |  -6.1  21.0  245  26 13   6.2   3.4
 18000  -6.2  20.8  240  28 15   6.0   3.3 |  -5.1  22.8  245  26 14   6.1   3.3
 17500  -5.3  22.5  240  29 15   6.2   3.4 |  -4.3  24.3  245  28 14   6.0   3.3
 17000  -4.4  24.1  235  29 15   6.2   3.4 |  -3.4  25.9  240  29 15   6.0   3.3
 16500  -3.3  26.1  235  29 15   8.7   4.8 |  -2.4  27.7  240  30 15   7.6   4.1
 16000  -2.1  28.2  235  29 15   8.6   4.7 |  -1.4  29.5  235  31 16   7.6   4.2
 15500  -0.9  30.4  235  29 15   8.9   4.9 |  -0.3  31.5  235  31 16   7.7   4.2
 15000   0.4  32.7  235  29 15   9.0   4.9 |   0.7  33.3  235  31 16   7.8   4.3
 14500   1.7  35.1  230  29 15   8.9   4.9 |   1.8  35.2  235  31 16   8.1   4.5
 14000   3.0  37.4  230  28 15   8.8   4.8 |   3.0  37.4  235  30 15   8.4   4.6
 13500   4.2  39.6  230  28 14   8.9   4.9 |   4.7  40.5  235  27 14   7.9   4.3
 13000   6.2  43.2  235  26 13   9.0   4.9 |   5.8  42.4  235  24 13   7.8   4.3
 12500   7.5  45.5  235  25 13   8.8   4.8 |   6.9  44.4  235  22 11   7.5   4.1
 12000   8.7  47.7  235  23 12   8.6   4.7 |   8.0  46.4  235  19 10   7.3   4.0
 11500  10.0  50.0  240  21 11   7.9   4.3 |   9.1  48.4  235  16  8   7.7   4.2
 11000  11.0  51.8  240  19 10   7.0   3.8 |  10.2  50.4  240  14  7   7.8   4.3
 10500  12.1  53.8  245  17  9   4.5   2.5 |  11.4  52.5  240  12  6   4.2   2.3
 10250  12.3  54.1  245  17  9   6.5   3.6 |  11.6  52.9  245  12  6   6.1   3.4
 10000  13.1  55.6  245  16  8  11.0   6.0 |  12.4  54.3  245  11  6  11.5   6.3
  9750  13.8  56.8  245  15  8  10.7   5.9 |  13.1  55.6  245  11  6  10.5   5.8
  9500  14.6  58.3  245  14  7   7.4   4.0 |  13.8  56.8  245  10  5   8.0   4.4
  9250  14.9  58.8  240  13  6   5.3   2.9 |  14.3  57.7  245  10  5   7.0   3.8
  9000  15.5  59.9  235  11  6   8.4   4.6 |  15.0  59.0  245   9  5   9.5   5.2
  8750  16.1  61.0  230  10  5   8.4   4.6 |  15.7  60.3  245   8  4   9.5   5.2
  8500  16.7  62.1  225   9  5   7.2   3.9 |  16.4  61.5  245   8  4   8.9   4.9
  8250  17.1  62.8  220   8  4   6.1   3.4 |  16.9  62.4  245   7  4   8.5   4.7
  8000  17.6  63.7  215   7  4   6.3   3.5 |  17.5  63.5  250   6  3   8.4   4.6
  7750  18.0  64.4  210   7  4   5.8   3.2 |  18.1  64.6  250   6  3   8.7   4.8
  7500  18.4  65.1  205   7  4   4.9   2.7 |  18.8  65.8  250   6  3   9.9   5.4
  7250  18.7  65.7  200   7  4   4.1   2.3 |  19.5  67.1  250   6  3  10.3   5.7
  7000  19.0  66.2  195   8  4   5.2   2.9 |  20.3  68.5  250   6  3  10.0   5.5
  6750  19.4  66.9  190   9  4   5.1   2.8 |  21.0  69.8  250   6  3  10.4   5.7
  6500  19.7  67.5  185   9  4   3.6   2.0 |  21.8  71.2  250   6  3  11.0   6.0
  6250  19.9  67.8  180   8  4   4.1   2.3 |  22.6  72.7  250   6  3  11.1   6.1
  6000  20.1  68.2  175   8  4   2.4   1.3 |  23.4  74.1  250   6  3  10.3   5.6
  5750  20.1  68.2  170   7  4   5.4   3.0 |  24.2  75.6  250   5  3  12.1   6.6
  5500  20.7  69.3  170   7  3  10.4   5.7 |  25.2  77.4  250   6  3  14.7   8.1
  5250  21.3  70.3  170   6  3   6.5   3.6 |  26.2  79.2  250   6  3  12.7   6.9
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/23/2015 at 1500 MDT          |       07/23/2015 at 1800 MDT
                                           |
K index... +22.6  LI... +273.6             | K index... +23.0  LI... +273.7
CAPE... 0.0  CIN... -2.8                   | CAPE... 0.0  CIN... -1.6
                                           |
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 -66.2 -87.2  235  32 16   1.3   0.7 | -66.2 -87.2  230  38 19   1.3   0.7
 45000 -61.5 -78.7  240  46 24   7.0   3.9 | -61.4 -78.5  235  51 26   7.0   3.8
 40000 -50.5 -58.9  240  53 27   6.8   3.7 | -50.5 -58.9  245  55 28   7.0   3.9
 38000 -46.4 -51.5  240  51 26   6.8   3.7 | -46.2 -51.2  245  53 27   7.0   3.9
 36000 -42.3 -44.1  245  50 26   7.2   4.0 | -42.0 -43.6  245  51 26   7.3   4.0
 34000 -37.6 -35.7  245  47 24   7.9   4.3 | -37.4 -35.3  245  47 24   7.7   4.2
 32000 -32.9 -27.2  245  43 22   8.0   4.4 | -32.8 -27.0  245  43 22   7.8   4.3
 30000 -28.7 -19.7  245  38 20   6.9   3.8 | -28.5 -19.3  245  38 20   7.2   3.9
 29000 -26.6 -15.9  250  36 18   6.9   3.8 | -26.4 -15.5  245  36 18   7.2   3.9
 28000 -24.0 -11.2  250  33 17   8.0   4.4 | -23.6 -10.5  245  32 16   8.1   4.4
 27000 -21.6  -6.9  250  31 16   7.9   4.4 | -21.2  -6.2  235  27 14   8.0   4.4
 26000 -19.2  -2.6  250  29 15   7.9   4.4 | -18.8  -1.8  225  23 12   8.0   4.4
 25000 -16.8   1.8  250  26 14   7.4   4.0 | -16.4   2.5  210  20 10   7.2   4.0
 24000 -14.7   5.5  250  26 13   7.0   3.8 | -14.4   6.1  220  20 10   6.7   3.7
 23000 -12.7   9.1  245  25 13   7.0   3.8 | -12.4   9.7  230  20 10   6.7   3.7
 22000 -10.6  12.9  245  24 12   5.6   3.1 | -10.4  13.3  240  21 11   5.5   3.0
 21000  -9.1  15.6  240  24 12   4.9   2.7 |  -8.9  16.0  240  23 12   4.8   2.7
 20000  -7.7  18.1  240  24 12   4.9   2.7 |  -7.5  18.5  245  24 12   4.8   2.7
 19500  -7.0  19.4  240  23 12   5.0   2.7 |  -6.8  19.8  245  25 13   4.9   2.7
 19000  -6.2  20.8  240  24 12   5.7   3.1 |  -5.9  21.4  245  25 13   6.1   3.3
 18500  -5.3  22.5  240  25 13   5.7   3.1 |  -5.0  23.0  245  25 13   6.1   3.3
 18000  -4.5  23.9  240  26 13   5.5   3.0 |  -4.2  24.4  245  25 13   5.8   3.2
 17500  -3.7  25.3  240  27 14   5.6   3.1 |  -3.4  25.9  245  26 13   6.0   3.3
 17000  -2.9  26.8  240  29 15   6.0   3.3 |  -2.6  27.3  240  26 14   6.5   3.5
 16500  -2.0  28.4  240  30 15   7.9   4.4 |  -1.5  29.3  240  26 13   8.7   4.8
 16000  -0.9  30.4  240  30 15   8.1   4.4 |  -0.4  31.3  240  25 13   8.8   4.8
 15500   0.2  32.4  240  29 15   8.3   4.5 |   0.8  33.4  240  23 12   8.9   4.9
 15000   1.3  34.3  235  27 14   8.4   4.6 |   2.1  35.8  240  21 11   8.9   4.9
 14500   2.4  36.3  235  26 13   8.6   4.7 |   3.3  37.9  235  19 10   9.1   5.0
 14000   3.7  38.7  235  24 12   8.8   4.8 |   4.6  40.3  235  18  9   9.2   5.0
 13500   5.6  42.1  235  21 11   8.6   4.7 |   6.6  43.9  235  15  8   8.7   4.8
 13000   6.8  44.2  235  19 10   8.6   4.7 |   7.9  46.2  230  14  7   8.7   4.8
 12500   8.1  46.6  235  17  9   8.4   4.6 |   9.2  48.6  230  12  6   8.6   4.7
 12000   9.3  48.7  235  15  8   8.3   4.6 |  10.5  50.9  230  11  6   8.5   4.7
 11500  10.5  50.9  235  13  7   7.8   4.3 |  11.7  53.1  235  10  5   8.1   4.4
 11000  11.6  52.9  235  11  6   7.4   4.0 |  12.9  55.2  235   8  4   7.6   4.2
 10500  12.7  54.9  240  10  5   3.9   2.2 |  14.0  57.2  235   7  4   4.6   2.5
 10250  12.9  55.2  240   9  5   5.5   3.0 |  14.3  57.7  235   7  3   5.6   3.1
 10000  13.6  56.5  245   8  4   9.5   5.2 |  15.0  59.0  240   6  3  10.1   5.5
  9750  14.2  57.6  250   7  3   8.7   4.8 |  15.6  60.1  240   6  3   9.4   5.1
  9500  14.8  58.6  260   6  3   6.5   3.6 |  16.3  61.3  245   5  3   7.5   4.1
  9250  15.2  59.4  265   5  3   6.3   3.5 |  16.8  62.2  245   5  3   6.3   3.5
  9000  15.8  60.4  270   5  3   9.0   5.0 |  17.3  63.1  250   4  2   7.7   4.2
  8750  16.5  61.7  280   5  3   8.9   4.9 |  17.9  64.2  255   4  2   7.5   4.1
  8500  17.1  62.8  285   5  3   9.2   5.1 |  18.5  65.3  265   3  2   6.9   3.8
  8250  17.8  64.0  285   5  3   9.4   5.2 |  18.9  66.0  275   3  2   6.5   3.6
  8000  18.5  65.3  290   6  3  10.0   5.5 |  19.4  66.9  290   3  2   6.9   3.8
  7750  19.3  66.7  290   6  3  10.5   5.7 |  20.0  68.0  295   3  2   7.7   4.2
  7500  20.1  68.2  290   6  3  10.4   5.7 |  20.6  69.1  295   4  2   9.5   5.2
  7250  20.8  69.4  285   6  3  10.5   5.8 |  21.4  70.5  295   4  2  10.7   5.9
  7000  21.6  70.9  285   6  3  10.3   5.6 |  22.1  71.8  295   4  2   9.7   5.3
  6750  22.3  72.1  285   6  3  10.3   5.7 |  22.8  73.0  295   4  2   9.7   5.3
  6500  23.1  73.6  285   6  3  10.5   5.8 |  23.6  74.5  295   4  2  10.5   5.8
  6250  23.9  75.0  285   6  3  10.7   5.9 |  24.4  75.9  290   4  2  10.9   6.0
  6000  24.7  76.5  285   6  3   9.9   5.5 |  25.2  77.4  290   4  2   9.4   5.2
  5750  25.5  77.9  285   6  3  12.3   6.7 |  25.8  78.4  290   4  2   9.4   5.2
  5500  26.5  79.7  285   6  3  15.3   8.4 |  26.6  79.9  290   4  2  11.3   6.2
  5250  27.6  81.7  285   6  3  12.9   7.1 |  27.4  81.3  290   4  2   9.8   5.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

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

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

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

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

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

DEFINITIONS:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

042613


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