Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 211230
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0630 MDT Thursday, August 21, 2014

This forecast is for Thursday, August 21, 2014:

If the trigger temperature of 74.0 F/23.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 703 ft/min (3.6 m/s)
   Maximum height of thermals.................. 15639 ft MSL (10800 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1000 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................. 12110 ft MSL (7271 ft AGL)
Thermal soaring outlook for Friday 08/22....... Good

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

Remarks...

Sunrise/Sunset.................... 06:32:51 / 20:02:09 MDT
Total possible sunshine........... 13 hr 29 min 18 sec (809 min 18 sec)
Altitude of sun at 13:17:07 MDT... 62.82 degrees

Upper air data from rawinsonde observation taken on 08/21/2014 at 0600 MDT

Freezing level.................. 13801 ft MSL (8962 ft AGL)
Convective condensation level... 13449 ft MSL (8610 ft AGL)
Lifted condensation level....... 14525 ft MSL (9686 ft AGL)
Lifted index.................... +0.9
K index......................... +19.3

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  -66.2 -87.2   220   31   16  -0.8  -0.5   83.7 182.7    31.5      M    M
 45000  -59.2 -74.6   220   55   28   7.5   4.1   70.9 159.7    25.8      M    M
 40000  -51.4 -60.5   215   74   38   8.6   4.7   60.5 140.9    20.7      M    M
 38000  -46.2 -51.2   215   65   34   8.7   4.8   59.6 139.3    20.6      M    M
 36000  -44.4 -47.9   235   70   36   6.5   3.5   53.7 128.7    17.0      M    M
 34000  -40.1 -40.2   230   71   36   8.2   4.5   50.6 123.1    15.2      M    M
 32000  -34.6 -30.3   225   71   37   9.4   5.1   50.0 122.0    15.1      M    M
 30000  -30.2 -22.4   225   64   33   5.9   3.2   48.3 118.9    14.1      M    M
 29000  -29.0 -20.2   225   54   28   5.4   3.0   45.9 114.7    12.5      M    M
 28000  -26.8 -16.2   230   44   23   7.4   4.1   45.1 113.1    12.0      M    M
 27000  -24.3 -11.7   235   43   22   8.3   4.5   44.4 111.9    11.6      M    M
 26000  -21.8  -7.2   240   43   22   8.3   4.5   43.9 111.0    11.4      M    M
 25000  -19.3  -2.7   230   38   20   8.3   4.5   43.3 110.0    11.1      M    M
 24000  -16.9   1.6   225   37   19   8.1   4.4   42.7 108.8    10.7      M    M
 23000  -14.4   6.1   230   37   19   6.6   3.6   42.0 107.6    10.3      M    M
 22000  -12.9   8.8   230   37   19   3.2   1.7   40.4 104.7     9.1      M    M
 21000  -11.7  10.9   235   37   19   2.3   1.3   38.4 101.1     7.4      M    M
 20000  -11.4  11.5   250   33   17   7.7   4.2   35.5  95.9     4.9      M    M
 19500  -10.8  12.6   250   32   16  -0.8  -0.5   34.4  93.9     3.9      M    M
 19000   -9.9  14.2   245   29   15   7.0   3.9   33.0  91.4     2.7      M    M
 18500   -9.1  15.6   240   28   14   7.2   4.0   32.1  89.8     2.0      M    M
 18000   -8.0  17.6   235   27   14   7.6   4.2   31.8  89.2     1.7      M    M
 17500   -6.9  19.6   235   26   13   7.8   4.3   31.4  88.6     1.3      M    M
 17000   -5.7  21.7   230   25   13   8.0   4.4   31.1  88.0     1.1      M    M
 16500   -4.5  23.9   240   22   12   8.0   4.4   30.8  87.5     0.8      M    M
 16000   -3.4  25.9   245   20   11   6.0   3.3   30.5  86.9     0.5      M    M
 15500   -2.8  27.0   250   17    9   5.4   2.9   29.7  85.4    -0.3    888  4.5
 15000   -1.9  28.6   255   14    7   5.7   3.1   29.0  84.2    -1.0    849  4.3
 14500   -1.2  29.8   255   10    5   3.1   1.7   28.2  82.8    -1.7    813  4.1
 14000   -0.5  31.1   250    7    4  10.1   5.5   27.6  81.7    -2.5    777  3.9
 13500    1.1  34.0   260    8    4  10.2   5.6   27.6  81.8    -2.3    713  3.6
 13000    2.3  36.1   265    9    5   7.2   3.9   27.4  81.3    -2.6    662  3.4
 12500    3.6  38.5   270   11    5   9.2   5.0   27.2  81.0    -2.8    609  3.1
 12000    4.7  40.5   275   12    6   7.1   3.9   27.0  80.5    -3.1    561  2.8
 11500    5.6  42.1   275   12    6   7.9   4.3   26.6  79.9    -3.7    519  2.6
 11000    6.9  44.4   280   12    6   8.0   4.4   26.3  79.4    -3.9    466  2.4
 10500    8.2  46.8   280   12    6   8.0   4.4   26.1  78.9    -4.1    412  2.1
 10250    8.8  47.8   280   12    6   7.2   3.9   25.9  78.6    -4.2    387  2.0
 10000    9.3  48.7   275   11    6   6.4   3.5   25.7  78.2    -4.5    364  1.8
  9750    9.8  49.6   275   11    5   6.2   3.4   25.4  77.7    -4.8    343  1.7
  9500   10.2  50.4   270   10    5   6.3   3.5   25.1  77.2    -5.1    323  1.6
  9250   10.6  51.1   270   10    5   6.3   3.5   24.8  76.7    -5.4    302  1.5
  9000   11.1  52.0   265    9    5   6.3   3.5   24.6  76.2    -5.7    282  1.4
  8750   11.5  52.7   260    7    4   8.3   4.5   24.4  75.8    -5.9    260  1.3
  8500   12.2  54.0   245    6    3   9.8   5.4   24.3  75.8    -6.0    232  1.2
  8250   12.9  55.2   225    4    2   9.2   5.0   24.3  75.8    -6.0    203  1.0
  8000   13.6  56.5   195    4    2  10.0   5.5   24.3  75.7    -6.1    175  0.9
  7750   14.3  57.7   185    3    2   7.3   4.0   24.3  75.7    -6.1    147  0.7
  7500   14.7  58.5   165    2    1   4.3   2.4   23.9  75.0    -6.5    129  0.7
  7250   15.0  59.0   120    1    1   4.8   2.6   23.5  74.3    -7.0    112  0.6
  7000   15.3  59.5   070    2    1   4.7   2.6   23.1  73.6    -7.4     95  0.5
  6750   15.6  60.1   070    2    1   4.7   2.6   22.7  72.9    -7.8     78  0.4
  6500   16.0  60.8   075    2    1   4.7   2.6   22.4  72.2    -8.2     61  0.3
  6250   16.3  61.3   080    3    1   4.7   2.6   22.0  71.6    -8.7     44  0.2
  6000   16.6  61.9   085    3    2   4.8   2.6   21.6  70.9    -9.1     27  0.1
  5750   16.9  62.4   090    3    2   4.7   2.6   21.2  70.2    -9.5     10  0.1
  5500   17.2  63.0   095    3    2   5.1   2.8   20.8  69.5   -10.0      M    M
  5250   17.6  63.7   100    3    2   3.6   2.0   20.5  68.8   -10.4      M    M
  5000   17.5  63.5   105    3    2  -8.1  -4.4   19.7  67.4   -11.3      M    M

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

           08/21/2014 at 0900 MDT          |       08/21/2014 at 1200 MDT
                                           |
K index... +19.5  LI... -1.2               | K index... +16.0  LI... -2.1
CAPE... +59.5  CIN... -35.1                | CAPE... +185.7  CIN... -24.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.1 -81.6  220  35 18   1.1   0.6 | -62.3 -80.1  225  33 17   2.3   1.3
 45000 -59.7 -75.5  220  57 29   4.9   2.7 | -58.5 -73.3  225  55 28   3.2   1.7
 40000 -52.1 -61.8  220  73 37   6.7   3.7 | -53.1 -63.6  220  81 42   7.6   4.2
 38000 -48.0 -54.4  220  75 38   6.8   3.7 | -48.6 -55.5  220  81 42   7.6   4.2
 36000 -43.9 -47.0  225  77 40   6.7   3.7 | -44.0 -47.2  225  82 42   7.6   4.2
 34000 -39.5 -39.1  225  73 38   7.6   4.2 | -39.6 -39.3  225  74 38   7.3   4.0
 32000 -34.4 -29.9  230  68 35   7.5   4.1 | -34.7 -30.5  230  64 33   7.1   3.9
 30000 -30.3 -22.5  230  56 29   6.6   3.6 | -30.8 -23.4  225  53 27   6.3   3.5
 29000 -28.4 -19.1  230  49 25   6.6   3.6 | -28.9 -20.0  225  47 24   6.4   3.5
 28000 -26.4 -15.5  230  42 22   6.8   3.7 | -27.0 -16.6  225  42 21   7.0   3.8
 27000 -24.3 -11.7  230  39 20   6.9   3.8 | -24.7 -12.5  225  38 20   7.7   4.2
 26000 -22.2  -8.0  230  36 19   6.9   3.8 | -22.4  -8.3  225  35 18   7.7   4.2
 25000 -20.1  -4.2  230  34 17   7.0   3.9 | -20.1  -4.2  225  32 16   7.8   4.3
 24000 -18.2  -0.8  235  32 16   6.2   3.4 | -18.2  -0.8  225  29 15   6.0   3.3
 23000 -16.4   2.5  240  30 16   6.2   3.4 | -16.4   2.5  230  27 14   6.1   3.3
 22000 -14.6   5.7  245  29 15   6.2   3.4 | -14.6   5.7  240  26 13   6.0   3.3
 21000 -12.8   9.0  245  26 13   5.8   3.2 | -12.8   9.0  245  24 12   5.9   3.2
 20000 -11.1  12.0  250  23 12   5.8   3.2 | -11.1  12.0  250  22 11   5.9   3.2
 19500 -10.3  13.5  250  22 11   5.8   3.2 | -10.2  13.6  250  22 11   5.8   3.2
 19000  -9.4  15.1  255  21 11   6.4   3.5 |  -9.3  15.3  255  21 11   6.8   3.7
 18500  -8.4  16.9  255  21 11   6.6   3.6 |  -8.2  17.2  255  21 11   6.9   3.8
 18000  -7.4  18.7  255  21 11   6.6   3.6 |  -7.2  19.0  255  20 11   6.9   3.8
 17500  -6.4  20.5  260  20 11   6.9   3.8 |  -6.2  20.8  255  21 11   7.0   3.9
 17000  -5.4  22.3  260  20 11   7.0   3.8 |  -5.1  22.8  260  21 11   7.0   3.9
 16500  -4.4  24.1  260  20 11   6.5   3.6 |  -4.1  24.6  260  21 11   6.6   3.6
 16000  -3.4  25.9  260  21 11   6.5   3.6 |  -3.1  26.4  260  21 11   6.6   3.6
 15500  -2.5  27.5  260  21 11   6.5   3.5 |  -1.7  28.9  265  20 11   6.8   3.7
 15000  -1.1  30.0  265  20 10   6.5   3.5 |  -0.6  30.9  265  20 10   6.8   3.7
 14500  -0.2  31.6  265  20 10   6.9   3.8 |   0.4  32.7  265  19 10   6.9   3.8
 14000   0.8  33.4  260  18  9   7.1   3.9 |   1.4  34.5  265  19 10   7.0   3.8
 13500   1.8  35.2  260  17  9   7.4   4.1 |   2.4  36.3  260  18  9   7.3   4.0
 13000   2.8  37.0  260  15  8   7.7   4.2 |   3.5  38.3  260  18  9   7.6   4.2
 12500   3.9  39.0  260  13  7   7.8   4.3 |   4.5  40.1  255  17  9   7.8   4.3
 12000   5.0  41.0  255  12  6   7.7   4.2 |   5.6  42.1  255  16  8   8.2   4.5
 11500   6.1  43.0  255  11  6   7.7   4.2 |   6.8  44.2  250  14  7   8.4   4.6
 11000   7.2  45.0  250   9  5   7.5   4.1 |   7.9  46.2  250  12  6   8.4   4.6
 10500   8.3  46.9  250   7  3   4.0   2.2 |   9.1  48.4  245  11  6   5.2   2.9
 10250   8.4  47.1  245   6  3   5.5   3.0 |   9.4  48.9  240  10  5   6.0   3.3
 10000   9.2  48.6  245   5  3  11.2   6.1 |  10.1  50.2  240   9  5  10.9   6.0
  9750   9.9  49.8  235   5  2  10.3   5.6 |  10.8  51.4  235   9  4  10.2   5.6
  9500  10.6  51.1  230   4  2   8.4   4.6 |  11.5  52.7  230   8  4   8.2   4.5
  9250  11.1  52.0  220   4  2   6.0   3.3 |  11.9  53.4  230   7  4   6.2   3.4
  9000  11.6  52.9  215   4  2   7.7   4.2 |  12.4  54.3  230   7  3   7.9   4.4
  8750  12.2  54.0  205   4  2   8.6   4.7 |  13.0  55.4  225   6  3   8.3   4.6
  8500  12.7  54.9  200   4  2   7.4   4.1 |  13.6  56.5  225   5  3   7.5   4.1
  8250  13.2  55.8  190   4  2   6.5   3.5 |  14.1  57.4  225   5  3   6.5   3.6
  8000  13.7  56.7  185   5  2   7.1   3.9 |  14.6  58.3  225   5  2   8.1   4.5
  7750  14.2  57.6  185   5  3   7.2   3.9 |  15.2  59.4  225   4  2   9.7   5.3
  7500  14.7  58.5  180   5  3   6.1   3.3 |  15.9  60.6  225   4  2   9.8   5.4
  7250  15.1  59.2  180   6  3   5.8   3.2 |  16.7  62.1  225   4  2  10.4   5.7
  7000  15.6  60.1  175   6  3   5.1   2.8 |  17.5  63.5  230   4  2   9.4   5.1
  6750  15.9  60.6  170   7  3   3.9   2.1 |  18.1  64.6  230   4  2   9.6   5.3
  6500  16.2  61.2  170   6  3   3.9   2.1 |  18.9  66.0  230   4  2  11.0   6.1
  6250  16.5  61.7  165   6  3   4.0   2.2 |  19.8  67.6  230   4  2  11.2   6.2
  6000  16.8  62.2  165   5  3   3.9   2.1 |  20.6  69.1  235   4  2  10.4   5.7
  5750  17.1  62.8  155   4  2   6.8   3.7 |  21.4  70.5  235   4  2  12.3   6.8
  5500  17.7  63.9  155   4  2   9.5   5.2 |  22.4  72.3  235   4  2  15.0   8.3
  5250  18.4  65.1  155   4  2   7.5   4.1 |  23.4  74.1  240   4  2  12.9   7.1
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/21/2014 at 1500 MDT          |       08/21/2014 at 1800 MDT
                                           |
K index... +19.9  LI... -1.7               | K index... +14.4  LI... +0.8
CAPE... +107.9  CIN... -43.2               | CAPE... 0.0  CIN... -0.1
                                           |
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 -62.7 -80.9  215  34 18   2.6   1.4 | -63.4 -82.1  215  39 20   1.7   0.9
 45000 -58.5 -73.3  220  56 29   3.1   1.7 | -59.7 -75.5  215  61 31   4.3   2.4
 40000 -52.8 -63.0  215  84 43   7.7   4.2 | -52.7 -62.9  220  80 41   7.3   4.0
 38000 -48.1 -54.6  220  83 43   7.7   4.2 | -48.3 -54.9  220  80 41   7.4   4.1
 36000 -43.5 -46.3  225  82 42   7.8   4.3 | -43.8 -46.8  225  81 42   7.4   4.1
 34000 -39.1 -38.4  225  74 38   7.3   4.0 | -39.6 -39.3  230  72 37   6.9   3.8
 32000 -34.7 -30.5  230  65 33   7.1   3.9 | -34.9 -30.8  230  59 30   6.6   3.6
 30000 -30.4 -22.7  230  55 28   7.3   4.0 | -30.3 -22.5  225  53 27   7.9   4.3
 29000 -28.3 -18.9  225  50 26   7.3   4.0 | -28.0 -18.4  225  51 26   7.9   4.3
 28000 -26.1 -15.0  225  46 23   7.0   3.8 | -25.6 -14.1  220  48 25   6.8   3.7
 27000 -24.3 -11.7  225  42 22   6.0   3.3 | -23.8 -10.8  225  44 23   6.2   3.4
 26000 -22.1  -7.8  220  38 19   6.0   3.3 | -22.0  -7.6  225  40 21   6.2   3.4
 25000 -20.3  -4.5  220  34 18   6.1   3.3 | -20.1  -4.2  230  36 18   6.2   3.4
 24000 -18.4  -1.1  220  30 15   6.5   3.6 | -18.2  -0.8  230  32 17   6.7   3.7
 23000 -16.5   2.3  225  26 13   6.5   3.6 | -16.2   2.8  230  29 15   6.7   3.7
 22000 -14.5   5.9  230  22 11   6.3   3.5 | -14.2   6.4  225  26 13   6.6   3.6
 21000 -12.7   9.1  235  21 11   5.9   3.2 | -12.4   9.7  225  22 11   6.1   3.4
 20000 -11.0  12.2  240  20 11   5.9   3.2 | -10.6  12.9  225  18 10   6.1   3.4
 19500 -10.1  13.8  245  20 10   5.7   3.2 |  -9.6  14.7  225  17  9   6.1   3.3
 19000  -9.1  15.6  245  20 10   7.3   4.0 |  -8.7  16.3  230  15  8   6.9   3.8
 18500  -8.1  17.4  250  21 11   7.2   4.0 |  -7.6  18.3  235  15  8   7.0   3.8
 18000  -7.0  19.4  250  21 11   7.4   4.1 |  -6.6  20.1  235  15  8   7.0   3.9
 17500  -5.9  21.4  250  21 11   7.7   4.2 |  -5.5  22.1  240  15  8   7.2   3.9
 17000  -4.7  23.5  250  21 11   7.7   4.2 |  -4.4  24.1  245  15  8   7.1   3.9
 16500  -3.6  25.5  255  21 11   7.4   4.1 |  -3.3  26.1  250  15  8   7.6   4.2
 16000  -2.5  27.5  255  20 11   7.5   4.1 |  -2.2  28.0  250  16  8   7.6   4.2
 15500  -1.4  29.5  255  20 10   7.5   4.1 |  -0.5  31.1  255  16  8   8.2   4.5
 15000  -0.4  31.3  250  20 10   7.6   4.2 |   0.7  33.3  255  16  8   8.2   4.5
 14500   0.7  33.3  250  20 10   7.7   4.2 |   1.9  35.4  255  16  8   8.4   4.6
 14000   1.8  35.2  250  19 10   7.9   4.3 |   3.2  37.8  255  16  8   8.4   4.6
 13500   2.9  37.2  250  18  9   7.9   4.3 |   4.4  39.9  255  16  8   8.7   4.8
 13000   4.7  40.5  250  17  9   8.2   4.5 |   5.7  42.3  255  15  8   8.9   4.9
 12500   5.8  42.4  250  16  8   8.7   4.8 |   7.0  44.6  250  15  8   9.0   4.9
 12000   7.1  44.8  250  16  8   9.0   5.0 |   8.3  46.9  250  14  7   9.1   5.0
 11500   8.4  47.1  250  15  8   8.6   4.7 |   9.6  49.3  250  13  7   8.9   4.9
 11000   9.6  49.3  250  14  7   7.9   4.3 |  10.9  51.6  250  12  6   8.4   4.6
 10500  10.8  51.4  250  13  6   5.0   2.7 |  12.2  54.0  255  12  6   5.1   2.8
 10250  11.0  51.8  250  12  6   5.7   3.2 |  12.5  54.5  255  11  6   5.6   3.1
 10000  11.7  53.1  250  12  6  10.1   5.5 |  13.2  55.8  255  11  5  10.4   5.7
  9750  12.4  54.3  250  11  6   9.6   5.3 |  13.9  57.0  255  10  5   9.6   5.3
  9500  13.1  55.6  255  11  5   7.2   4.0 |  14.6  58.3  260  10  5   8.1   4.5
  9250  13.5  56.3  255  10  5   5.4   3.0 |  15.1  59.2  260   9  5   6.5   3.6
  9000  14.0  57.2  260   9  4   7.3   4.0 |  15.6  60.1  260   9  5   7.7   4.2
  8750  14.5  58.1  265   8  4   7.2   4.0 |  16.2  61.2  265   8  4   7.9   4.4
  8500  15.1  59.2  270   7  4   7.7   4.2 |  16.8  62.2  265   8  4   7.4   4.1
  8250  15.6  60.1  275   7  3   8.1   4.4 |  17.3  63.1  270   7  3   6.9   3.8
  8000  16.1  61.0  280   6  3   9.2   5.1 |  17.8  64.0  275   6  3   6.5   3.6
  7750  16.8  62.2  280   6  3  10.2   5.6 |  18.2  64.8  280   5  2   6.0   3.3
  7500  17.6  63.7  280   6  3   9.9   5.4 |  18.7  65.7  285   4  2   8.1   4.5
  7250  18.3  64.9  280   6  3  10.0   5.5 |  19.3  66.7  285   4  2   9.7   5.3
  7000  19.1  66.4  280   6  3   9.9   5.4 |  20.0  68.0  285   3  2   9.0   5.0
  6750  19.8  67.6  280   6  3  10.4   5.7 |  20.6  69.1  285   3  2   9.3   5.1
  6500  20.6  69.1  280   6  3  10.8   5.9 |  21.3  70.3  285   3  2  10.1   5.6
  6250  21.4  70.5  280   6  3  11.0   6.1 |  22.1  71.8  285   3  2  10.6   5.8
  6000  22.2  72.0  280   6  3  10.3   5.6 |  22.9  73.2  285   3  2   9.9   5.4
  5750  23.0  73.4  280   6  3  12.3   6.8 |  23.6  74.5  285   3  2   9.5   5.2
  5500  24.0  75.2  280   6  3  15.1   8.3 |  24.3  75.7  285   3  2   9.8   5.4
  5250  25.0  77.0  280   6  3  13.0   7.1 |  25.0  77.0  285   3  2   9.5   5.2
  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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