Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 231219
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0619 MDT Saturday, August 23, 2014

This forecast is for Saturday, August 23, 2014:

If the trigger temperature of 68.1 F/20.0 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 379 ft/min (1.9 m/s)
   Maximum height of thermals.................. 12923 ft MSL (8084 ft AGL)

Forecast maximum temperature................... 79.0 F/26.6 C
Time of trigger temperature.................... 0845 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10806 ft MSL (5967 ft AGL)
Thermal soaring outlook for Sunday 08/24....... Fair

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

Remarks...

Sunrise/Sunset.................... 06:34:41 / 19:59:19 MDT
Total possible sunshine........... 13 hr 24 min 39 sec (804 min 39 sec)
Altitude of sun at 13:16:37 MDT... 62.14 degrees

Upper air data from rawinsonde observation taken on 08/23/2014 at 0600 MDT

Freezing level.................. 13909 ft MSL (9070 ft AGL)
Convective condensation level... 8628 ft MSL (3789 ft AGL)
Lifted condensation level....... 11227 ft MSL (6388 ft AGL)
Lifted index.................... -4.1
K index......................... +31.2

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  -61.4 -78.5   220   32   16   0.2   0.1   93.5 200.3    39.0      M    M
 45000  -57.4 -71.3   225   35   18   4.0   2.2   74.7 166.4    30.1      M    M
 40000  -48.9 -56.0   250   31   16   7.5   4.1   64.9 148.8    25.7      M    M
 38000  -46.8 -52.2   255   41   21 -16.5  -9.0   59.4 138.9    22.7      M    M
 36000  -47.0 -52.6   260   40   21   8.7   4.8   50.4 122.8    17.0      M    M
 34000  -43.0 -45.4   280   53   27   6.7   3.7   48.0 118.4    15.7      M    M
 32000  -37.8 -36.0   250   40   21   6.8   3.7   46.1 114.9    14.7      M    M
 30000  -32.5 -26.5   245   37   19   8.3   4.6   45.4 113.7    14.5      M    M
 29000  -30.1 -22.2   240   36   18   8.4   4.6   44.9 112.7    14.3      M    M
 28000  -27.8 -18.0   240   34   18   7.3   4.0   44.0 111.2    13.8      M    M
 27000  -25.5 -13.9   240   33   17   6.9   3.8   43.3 109.9    13.3      M    M
 26000  -23.5 -10.3   235   31   16   7.8   4.3   42.1 107.7    12.5      M    M
 25000  -21.2  -6.2   235   30   15   7.8   4.3   41.4 106.5    12.1      M    M
 24000  -19.6  -3.3   235   29   15   3.2   1.8   39.9 103.8    10.9      M    M
 23000  -17.4   0.7   235   28   14   8.5   4.7   39.0 102.1    10.3      M    M
 22000  -15.9   3.4   235   27   14   7.2   3.9   37.2  98.9     8.9      M    M
 21000  -13.9   7.0   240   25   13   6.7   3.7   36.1  97.0     8.1      M    M
 20000  -11.7  10.9   240   24   12   5.5   3.0   35.3  95.5     7.4      M    M
 19500  -11.0  12.2   240   27   14   6.3   3.5   34.4  94.0     6.7      M    M
 19000   -9.9  14.2   235   31   16   8.1   4.5   34.0  93.2     6.4      M    M
 18500   -8.7  16.3   235   32   16   7.6   4.2   33.7  92.7     6.1      M    M
 18000   -7.8  18.0   235   31   16   4.9   2.7   33.1  91.7     5.7      M    M
 17500   -7.2  19.0   235   31   16   3.1   1.7   32.1  89.9     4.8      M    M
 17000   -6.5  20.3   240   30   15   4.4   2.4   30.6  87.1     3.4      M    M
 16500   -5.9  21.4   240   29   15   5.4   2.9   29.7  85.4     2.5      M    M
 16000   -4.6  23.7   240   29   15   9.7   5.3   29.6  85.3     2.4      M    M
 15500   -3.6  25.5   240   29   15   7.5   4.1   29.2  84.6     2.0      M    M
 15000   -2.5  27.5   235   29   15   7.7   4.2   28.8  83.9     1.6      M    M
 14500   -1.3  29.7   235   29   15   8.6   4.7   28.6  83.5     1.3      M    M
 14000   -0.1  31.8   235   29   15   8.8   4.8   28.4  83.1     1.1      M    M
 13500    1.0  33.8   240   33   17   5.7   3.1   28.1  82.5     0.8      M    M
 13000    1.7  35.1   240   36   18   5.4   3.0   27.3  81.2     0.0      M    M
 12500    2.5  36.5   240   33   17   5.4   3.0   26.6  79.9    -0.7    544  2.8
 12000    3.2  37.8   240   30   15   5.5   3.0   26.0  78.7    -1.4    506  2.6
 11500    4.0  39.2   240   28   14   5.5   3.0   25.3  77.5    -2.1    468  2.4
 11000    4.8  40.6   235   26   13   5.5   3.0   24.6  76.3    -2.7    430  2.2
 10500    5.6  42.1   215   23   12   5.5   3.0   23.9  75.1    -3.4    392  2.0
 10250    6.0  42.8   205   23   12   5.5   3.0   23.6  74.5    -3.8    373  1.9
 10000    6.3  43.3   200   21   11   5.4   3.0   23.3  73.9    -4.1    354  1.8
  9750    6.7  44.1   200   19   10   5.4   3.0   22.9  73.2    -4.5    336  1.7
  9500    7.1  44.8   200   16    8   5.4   3.0   22.6  72.6    -4.9    317  1.6
  9250    7.5  45.5   200   14    7   5.4   3.0   22.2  72.0    -5.2    298  1.5
  9000    7.9  46.2   200   11    6   5.4   3.0   21.9  71.4    -5.6    279  1.4
  8750    8.3  46.9   200    9    5   5.3   2.9   21.6  70.8    -5.9    260  1.3
  8500    8.6  47.5   200    7    3   5.8   3.2   21.2  70.2    -6.3    241  1.2
  8250    9.1  48.4   200    5    2   6.7   3.7   20.9  69.7    -6.6    220  1.1
  8000    9.6  49.3   200    2    1   6.9   3.8   20.7  69.3    -6.8    198  1.0
  7750   10.1  50.2   200    2    1   6.8   3.7   20.5  68.9    -7.1    176  0.9
  7500   10.6  51.1   200    1    1   6.8   3.8   20.3  68.5    -7.3    154  0.8
  7250   11.0  51.8   200    1    0   6.8   3.8   20.1  68.1    -7.6    132  0.7
  7000   11.5  52.7   000    0    0   6.9   3.8   19.8  67.7    -7.8    111  0.6
  6750   12.0  53.6   095    1    1   6.7   3.7   19.6  67.3    -8.1     89  0.4
  6500   12.5  54.5   095    3    1   7.3   4.0   19.4  66.9    -8.4     67  0.3
  6250   13.0  55.4   095    4    2   5.4   3.0   19.2  66.5    -8.6     45  0.2
  6000   13.2  55.8   095    6    3   1.5   0.8   18.7  65.6    -9.2     31  0.2
  5750   13.2  55.8   095    5    3  -0.5  -0.3   18.0  64.4    -9.9     23  0.1
  5500   13.2  55.8   090    3    2   2.8   1.5   17.3  63.1   -10.7     16  0.1
  5250   13.6  56.5   085    2    1   6.4   3.5   16.9  62.5   -11.1      M    M
  5000   13.9  57.0   035    1    0   4.0   2.2   16.6  61.9   -11.4      M    M

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

           08/23/2014 at 0900 MDT          |       08/23/2014 at 1200 MDT
                                           |
K index... +30.3  LI... -1.8               | K index... +24.4  LI... -1.4
CAPE... +227.4  CIN... -14.4               | CAPE... +193.1  CIN... -0.9
                                           |
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 -60.0 -76.0  225  27 14   1.7   0.9 | -58.3 -72.9  225  22 11   2.2   1.2
 45000 -57.5 -71.5  230  44 23   1.7   0.9 | -55.7 -68.3  230  38 19   0.3   0.2
 40000 -54.4 -65.9  250  66 34   7.5   4.1 | -54.8 -66.6  250  66 34   7.3   4.0
 38000 -50.1 -58.2  260  64 33   7.1   3.9 | -50.7 -59.3  250  62 32   6.8   3.7
 36000 -45.9 -50.6  265  63 33   7.1   3.9 | -46.6 -51.9  250  57 30   6.8   3.7
 34000 -41.3 -42.3  270  66 34   8.0   4.4 | -42.0 -43.6  255  57 29   8.0   4.4
 32000 -36.4 -33.5  270  70 36   8.0   4.4 | -37.2 -35.0  260  59 31   8.0   4.4
 30000 -32.0 -25.6  270  68 35   6.9   3.8 | -32.2 -26.0  265  62 32   8.8   4.8
 29000 -29.9 -21.8  270  65 34   6.9   3.8 | -29.5 -21.1  265  63 33   8.8   4.8
 28000 -27.3 -17.1  275  62 32   6.9   3.8 | -26.3 -15.3  265  65 33   8.6   4.7
 27000 -25.5 -13.9  270  56 29   6.2   3.4 | -24.3 -11.7  265  63 33   6.2   3.4
 26000 -23.6 -10.5  270  48 25   6.3   3.5 | -22.4  -8.3  270  61 32   6.3   3.4
 25000 -21.8  -7.2  265  41 21   6.4   3.5 | -20.5  -4.9  270  59 30   6.3   3.4
 24000 -19.9  -3.8  260  38 19   6.3   3.4 | -18.8  -1.8  265  54 28   5.5   3.0
 23000 -18.1  -0.6  255  37 19   6.3   3.5 | -17.2   1.0  260  48 25   5.6   3.1
 22000 -16.3   2.7  255  36 18   6.4   3.5 | -15.6   3.9  250  43 22   5.9   3.2
 21000 -14.3   6.3  250  35 18   6.9   3.8 | -13.9   7.0  245  40 21   6.1   3.4
 20000 -12.3   9.9  250  36 18   6.9   3.8 | -12.1  10.2  245  39 20   6.2   3.4
 19500 -11.3  11.7  245  36 18   6.9   3.8 | -11.2  11.8  240  39 20   6.2   3.4
 19000 -10.3  13.5  245  36 18   6.7   3.7 | -10.3  13.5  240  38 20   6.2   3.4
 18500  -9.4  15.1  245  36 18   6.1   3.3 |  -9.4  15.1  240  37 19   6.2   3.4
 18000  -8.5  16.7  245  35 18   6.1   3.4 |  -8.6  16.5  245  36 19   6.2   3.4
 17500  -7.7  18.1  245  34 18   5.8   3.2 |  -7.7  18.1  245  35 18   6.0   3.3
 17000  -6.8  19.8  245  34 17   5.8   3.2 |  -6.8  19.8  250  33 17   6.0   3.3
 16500  -6.0  21.2  245  33 17   5.6   3.1 |  -5.9  21.4  250  32 16   5.4   3.0
 16000  -5.2  22.6  245  32 17   5.4   3.0 |  -5.3  22.5  255  31 16   4.5   2.5
 15500  -4.5  23.9  245  32 16   5.4   3.0 |  -4.6  23.7  260  31 16   4.5   2.5
 15000  -3.6  25.5  245  31 16   6.4   3.5 |  -3.8  25.2  260  30 15   5.6   3.1
 14500  -2.7  27.1  240  30 15   6.3   3.5 |  -3.0  26.6  265  30 15   5.5   3.0
 14000  -1.7  28.9  240  29 15   6.7   3.7 |  -2.2  28.0  265  29 15   5.6   3.1
 13500  -0.3  31.5  240  27 14   6.7   3.7 |  -1.0  30.2  265  28 14   5.7   3.1
 13000   0.6  33.1  240  27 14   6.1   3.3 |  -0.1  31.8  265  26 14   6.4   3.5
 12500   1.5  34.7  245  26 14   6.1   3.4 |   0.8  33.4  270  25 13   6.3   3.5
 12000   2.4  36.3  245  25 13   6.6   3.6 |   1.8  35.2  270  24 12   7.2   3.9
 11500   3.3  37.9  245  23 12   6.5   3.6 |   2.8  37.0  270  23 12   7.2   3.9
 11000   4.3  39.7  245  21 11   7.0   3.9 |   3.8  38.8  270  22 11   6.3   3.4
 10500   5.3  41.5  250  20 10   4.0   2.2 |   4.7  40.5  270  21 11   4.2   2.3
 10250   5.5  41.9  250  20 10   5.3   2.9 |   4.9  40.8  275  21 11   4.0   2.2
 10000   6.1  43.0  255  19 10  10.3   5.7 |   5.4  41.7  275  20 10   8.1   4.4
  9750   6.8  44.2  255  18  9   9.0   5.0 |   6.0  42.8  275  20 10   8.5   4.7
  9500   7.5  45.5  255  18  9   9.2   5.1 |   6.6  43.9  275  19 10   8.1   4.5
  9250   8.0  46.4  260  17  9   6.8   3.7 |   7.1  44.8  275  19 10   6.3   3.4
  9000   8.5  47.3  260  17  9   6.1   3.3 |   7.5  45.5  275  18  9   6.0   3.3
  8750   9.0  48.2  260  17  9   7.0   3.8 |   8.0  46.4  275  17  9   6.9   3.8
  8500   9.4  48.9  260  17  9   6.9   3.8 |   8.4  47.1  280  16  8   6.5   3.6
  8250  10.0  50.0  265  16  8   8.0   4.4 |   8.9  48.0  280  15  8   6.1   3.4
  8000  10.5  50.9  265  16  8   7.0   3.9 |   9.3  48.7  280  14  7   6.0   3.3
  7750  11.0  51.8  265  15  8   5.5   3.0 |   9.7  49.5  280  12  6   5.8   3.2
  7500  11.4  52.5  260  15  7   6.2   3.4 |  10.1  50.2  285  11  6   6.8   3.7
  7250  11.9  53.4  260  13  7   6.8   3.8 |  10.6  51.1  285  10  5   8.0   4.4
  7000  12.4  54.3  255  12  6   6.3   3.5 |  11.1  52.0  285   9  5   7.4   4.1
  6750  12.8  55.0  250  11  5   5.7   3.2 |  11.6  52.9  285   8  4   7.8   4.3
  6500  13.2  55.8  245   9  5   7.9   4.3 |  12.2  54.0  285   7  4  10.0   5.5
  6250  13.9  57.0  240   8  4   9.4   5.2 |  13.0  55.4  285   7  4  11.4   6.3
  6000  14.5  58.1  235   7  4   8.9   4.9 |  13.8  56.8  285   7  4  10.0   5.5
  5750  15.2  59.4  230   6  3   9.2   5.0 |  14.5  58.1  285   7  4  11.0   6.0
  5500  15.8  60.4  230   6  3   9.5   5.2 |  15.4  59.7  285   7  4  13.3   7.3
  5250  16.5  61.7  230   6  3   9.4   5.2 |  16.3  61.3  285   7  4  11.7   6.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/23/2014 at 1500 MDT          |       08/23/2014 at 1800 MDT
                                           |
K index... +24.2  LI... -0.8               | K index... +21.2  LI... -0.9
CAPE... +40.0  CIN... -12.8                | CAPE... +60.0  CIN... -60.1
                                           |
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 -59.0 -74.2  235  20 11   1.7   0.9 | -59.4 -74.9  240  23 12   1.2   0.7
 45000 -56.5 -69.7  240  36 18   1.8   1.0 | -57.0 -70.6  245  38 19   3.1   1.7
 40000 -53.5 -64.3  255  64 33   5.0   2.7 | -52.1 -61.8  260  60 31   3.3   1.8
 38000 -50.6 -59.1  255  62 32   4.9   2.7 | -50.2 -58.4  260  60 31   3.3   1.8
 36000 -47.6 -53.7  255  61 31   4.9   2.7 | -48.2 -54.8  265  60 31   3.3   1.8
 34000 -43.2 -45.8  255  61 31   8.6   4.7 | -44.1 -47.4  265  61 31   8.5   4.7
 32000 -38.0 -36.4  260  62 32   8.6   4.7 | -39.0 -38.2  265  61 31   8.5   4.7
 30000 -32.7 -26.9  260  62 32   9.0   4.9 | -33.7 -28.7  265  61 31   9.0   4.9
 29000 -29.4 -20.9  265  61 31   9.0   4.9 | -31.0 -23.8  265  61 31   9.0   4.9
 28000 -26.7 -16.1  265  61 31   8.8   4.8 | -27.7 -17.9  270  61 31   8.9   4.9
 27000 -24.3 -11.7  265  61 31   7.8   4.3 | -25.1 -13.2  270  61 31   8.6   4.7
 26000 -22.0  -7.6  270  61 32   7.8   4.3 | -22.5  -8.5  270  61 31   8.6   4.7
 25000 -19.6  -3.3  270  62 32   7.9   4.4 | -19.9  -3.8  270  61 31   8.7   4.8
 24000 -18.0  -0.4  265  59 31   4.0   2.2 | -17.9  -0.2  265  59 30   5.8   3.2
 23000 -16.9   1.6  260  54 28   4.1   2.2 | -16.2   2.8  265  56 29   5.8   3.2
 22000 -15.7   3.7  255  50 26   4.2   2.3 | -14.4   6.1  265  53 27   5.9   3.2
 21000 -14.1   6.6  250  47 24   6.3   3.5 | -13.1   8.4  260  51 26   4.2   2.3
 20000 -12.3   9.9  250  45 23   6.4   3.5 | -11.9  10.6  255  49 25   4.5   2.5
 19500 -11.4  11.5  245  44 23   6.4   3.5 | -11.3  11.7  250  48 25   4.8   2.6
 19000 -10.5  13.1  245  43 22   6.4   3.5 | -10.7  12.7  250  48 25   5.3   2.9
 18500  -9.6  14.7  245  42 22   6.2   3.4 |  -9.9  14.2  250  46 24   5.6   3.1
 18000  -8.7  16.3  245  41 21   6.2   3.4 |  -9.1  15.6  255  45 23   5.7   3.1
 17500  -7.8  18.0  245  39 20   7.0   3.8 |  -8.3  17.1  255  43 22   5.0   2.8
 17000  -6.8  19.8  250  39 20   6.9   3.8 |  -7.5  18.5  260  41 21   5.1   2.8
 16500  -5.8  21.6  250  38 19   5.5   3.0 |  -6.8  19.8  260  39 20   5.9   3.2
 16000  -5.2  22.6  255  37 19   4.2   2.3 |  -5.8  21.6  265  38 20   6.6   3.6
 15500  -4.5  23.9  255  37 19   4.3   2.3 |  -4.8  23.4  265  37 19   6.8   3.7
 15000  -3.7  25.3  255  37 19   6.5   3.6 |  -3.6  25.5  265  36 18   8.1   4.5
 14500  -2.8  27.0  255  36 18   6.3   3.5 |  -2.5  27.5  265  34 17   8.1   4.4
 14000  -1.8  28.8  260  35 18   7.3   4.0 |  -1.4  29.5  265  32 17   7.5   4.1
 13500  -0.2  31.6  260  35 18   7.1   3.9 |   0.2  32.4  265  30 15   7.7   4.2
 13000   0.7  33.3  260  34 17   6.1   3.3 |   1.4  34.5  260  28 15   8.2   4.5
 12500   1.7  35.1  260  32 17   6.1   3.4 |   2.6  36.7  260  27 14   8.2   4.5
 12000   2.6  36.7  260  30 16   6.6   3.6 |   3.8  38.8  260  26 14   8.1   4.5
 11500   3.6  38.5  260  28 14   6.5   3.6 |   5.0  41.0  255  25 13   8.1   4.4
 11000   4.6  40.3  260  26 13   6.6   3.6 |   6.2  43.2  255  24 13   8.0   4.4
 10500   5.5  41.9  260  23 12   4.3   2.4 |   7.4  45.3  255  23 12   4.9   2.7
 10250   5.8  42.4  255  22 11   5.4   3.0 |   7.6  45.7  255  23 12   5.4   3.0
 10000   6.4  43.5  260  20 11   9.3   5.1 |   8.3  46.9  260  22 11   9.9   5.4
  9750   7.0  44.6  260  19 10   8.4   4.6 |   8.9  48.0  260  21 11   8.8   4.8
  9500   7.6  45.7  260  18  9   8.2   4.5 |   9.5  49.1  260  20 11   8.7   4.8
  9250   8.1  46.6  260  16  8   7.1   3.9 |  10.1  50.2  260  20 10   6.1   3.4
  9000   8.6  47.5  260  15  8   7.7   4.2 |  10.5  50.9  260  18  9   5.5   3.0
  8750   9.2  48.6  260  13  7   8.4   4.6 |  10.9  51.6  265  16  8   6.3   3.5
  8500   9.8  49.6  260  12  6   8.3   4.6 |  11.3  52.3  265  15  8   6.1   3.3
  8250  10.4  50.7  265  11  6   8.4   4.6 |  11.7  53.1  270  13  7   6.0   3.3
  8000  11.0  51.8  265  10  5   8.8   4.8 |  12.2  54.0  275  10  5   6.0   3.3
  7750  11.6  52.9  265  10  5   9.0   4.9 |  12.5  54.5  280   8  4   5.5   3.0
  7500  12.3  54.1  270   9  5   9.6   5.3 |  12.9  55.2  285   6  3   7.6   4.2
  7250  13.0  55.4  270   9  5  10.3   5.6 |  13.6  56.5  290   6  3  10.3   5.6
  7000  13.7  56.7  270   9  5  10.1   5.6 |  14.3  57.7  290   6  3   9.5   5.2
  6750  14.5  58.1  270   9  5  10.4   5.7 |  15.0  59.0  290   6  3   8.9   4.9
  6500  15.3  59.5  270   9  5  10.7   5.9 |  15.7  60.3  290   5  3   9.8   5.4
  6250  16.1  61.0  270   9  4  11.2   6.2 |  16.5  61.7  290   5  3  10.4   5.7
  6000  16.9  62.4  270   9  4   9.8   5.4 |  17.2  63.0  290   5  3  10.5   5.7
  5750  17.6  63.7  270   8  4  10.7   5.8 |  18.0  64.4  290   5  3  10.2   5.6
  5500  18.5  65.3  270   8  4  13.4   7.3 |  18.7  65.7  290   5  3   9.4   5.2
  5250  19.4  66.9  270   8  4  11.8   6.5 |  19.4  66.9  290   5  3   9.6   5.3
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

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

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

                   North Latitude:  39 deg 07 min 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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