Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 041244
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0643 MDT Friday, September 4, 2015

This forecast is for Friday, September 4, 2015:

If the trigger temperature of 79.2 F/26.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9700 ft MSL (4861 ft AGL)

Forecast maximum temperature................... 80.0 F/27.1 C
Time of trigger temperature.................... 1345 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................. 6187 ft MSL (1348 ft AGL)
Thermal soaring outlook for Saturday 09/05..... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:45:20 / 19:41:44 MDT
Total possible sunshine........... 12 hr 56 min 24 sec (776 min 24 sec)
Altitude of sun at 13:13:05 MDT... 57.96 degrees

Upper air data from rawinsonde observation taken on 09/04/2015 at 0600 MDT

Freezing level.................. 14490 ft MSL (9651 ft AGL)
Convective condensation level... 14702 ft MSL (9863 ft AGL)
Lifted condensation level....... 13875 ft MSL (9036 ft AGL)
Lifted index.................... +1.5
K index......................... +23.4

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  -62.9 -81.2   235   26   13  -2.4  -1.3   90.6 195.1    37.0      M    M
 45000  -59.5 -75.1   235   52   27  -0.5  -0.3   71.9 161.4    28.0      M    M
 40000  -53.7 -64.7   240   65   34   6.5   3.5   57.1 134.8    20.2      M    M
 38000  -50.1 -58.2   240   67   34   4.4   2.4   53.7 128.7    18.5      M    M
 36000  -46.8 -52.2   235   61   31   6.9   3.8   50.0 122.0    16.4      M    M
 34000  -42.5 -44.5   235   56   29   7.2   3.9   47.9 118.2    15.2      M    M
 32000  -38.4 -37.1   230   51   26   7.2   4.0   45.5 114.0    13.9      M    M
 30000  -32.1 -25.8   230   45   23   9.1   5.0   45.1 113.3    14.0      M    M
 29000  -29.5 -21.1   225   44   22   7.0   3.9   44.8 112.6    13.9      M    M
 28000  -27.5 -17.5   220   43   22   6.5   3.6   43.6 110.4    13.1      M    M
 27000  -25.0 -13.0   210   42   22   8.7   4.8   43.0 109.4    12.8      M    M
 26000  -22.4  -8.3   205   42   22   9.0   5.0   42.7 108.8    12.7      M    M
 25000  -19.7  -3.5   200   43   22   8.6   4.7   42.5 108.4    12.6      M    M
 24000  -18.3  -0.9   200   40   21   8.4   4.6   40.7 105.2    11.2      M    M
 23000  -16.0   3.2   205   38   19   8.1   4.4   40.0 104.0    10.7      M    M
 22000  -14.3   6.3   205   35   18   1.8   1.0   38.5 101.4     9.6      M    M
 21000  -14.1   6.6   210   32   17   0.7   0.4   35.3  95.5     7.0      M    M
 20000  -12.6   9.3   215   30   16  18.5  10.2   33.7  92.6     5.6      M    M
 19500  -11.0  12.2   210   29   15   7.3   4.0   34.0  93.1     5.8      M    M
 19000   -9.9  14.2   200   28   14   8.2   4.5   33.7  92.6     5.5      M    M
 18500   -8.7  16.3   200   26   13   8.5   4.7   33.4  92.2     5.3      M    M
 18000   -7.6  18.3   200   24   13   4.4   2.4   33.0  91.4     4.9      M    M
 17500   -7.1  19.2   205   23   12   3.2   1.8   31.8  89.3     3.9      M    M
 17000   -6.7  19.9   205   21   11   3.0   1.6   30.7  87.3     3.0      M    M
 16500   -5.4  22.3   210   18    9   9.9   5.4   29.8  85.6     2.1      M    M
 16000   -4.0  24.8   210   17    9   9.4   5.2   29.7  85.5     2.1      M    M
 15500   -2.6  27.3   205   16    8   9.4   5.2   29.7  85.4     2.1      M    M
 15000   -1.2  29.8   205   16    8   9.4   5.2   29.6  85.3     2.0      M    M
 14500    0.2  32.4   210   16    8   9.4   5.2   29.6  85.2     2.0      M    M
 14000    1.6  34.9   215   16    8   9.5   5.2   29.5  85.1     1.9      M    M
 13500    3.0  37.4   220   16    8   8.5   4.6   29.4  84.9     1.8      M    M
 13000    4.2  39.6   225   16    8   8.3   4.6   29.1  84.4     1.5      M    M
 12500    5.4  41.7   230   17    9   8.3   4.6   28.9  84.1     1.3      M    M
 12000    6.6  43.9   235   17    9   8.4   4.6   28.7  83.7     1.1      M    M
 11500    7.8  46.0   240   18    9   8.4   4.6   28.5  83.3     0.9      M    M
 11000    9.0  48.2   245   19   10   8.4   4.6   28.3  82.9     0.6      M    M
 10500   10.2  50.4   240   22   11   8.4   4.6   28.0  82.5     0.4      M    M
 10250   10.9  51.6   240   23   12   8.3   4.6   27.9  82.3     0.3      M    M
 10000   11.5  52.7   240   22   11   8.2   4.5   27.8  82.1     0.1      M    M
  9750   12.1  53.8   240   19   10   8.2   4.5   27.7  81.8     0.0      M    M
  9500   12.7  54.9   240   17    9   8.2   4.5   27.6  81.6    -0.1    334  1.7
  9250   13.3  55.9   240   15    8   8.2   4.5   27.5  81.4    -0.2    309  1.6
  9000   13.9  57.0   240   12    6   8.2   4.5   27.4  81.2    -0.3    283  1.4
  8750   14.5  58.1   240    9    5   8.2   4.5   27.2  81.0    -0.5    258  1.3
  8500   15.1  59.2   235    7    3   8.2   4.5   27.1  80.8    -0.6    232  1.2
  8250   15.7  60.3   225    4    2   8.2   4.5   27.0  80.6    -0.7    207  1.1
  8000   16.3  61.3   190    2    1   8.3   4.5   26.9  80.4    -0.8    181  0.9
  7750   16.9  62.4   160    5    3   8.2   4.5   26.8  80.2    -1.0    156  0.8
  7500   17.5  63.5   155    9    5   8.5   4.7   26.6  80.0    -1.1    130  0.7
  7250   18.0  64.4   150   13    7   3.3   1.8   26.4  79.6    -1.3    108  0.5
  7000   18.0  64.4   150   17    9   0.6   0.3   25.7  78.3    -2.1    100  0.5
  6750   18.2  64.8   150   20   10   6.3   3.4   25.2  77.4    -2.6     86  0.4
  6500   18.8  65.8   145   22   11   8.1   4.4   25.1  77.1    -2.7     62  0.3
  6250   19.3  66.7   145   24   12   7.8   4.3   24.9  76.9    -2.9     38  0.2
  6000   19.9  67.8   145   26   14   7.2   4.0   24.8  76.6    -3.1     14  0.1
  5750   20.5  68.9   145   24   12   9.7   5.3   24.6  76.3    -3.3      M    M
  5500   21.0  69.8   140   19   10  -0.6  -0.4   24.5  76.0    -3.5      M    M
  5250   20.2  68.4   135   15    8 -13.0  -7.1   23.0  73.4    -5.0      M    M
  5000   19.4  66.9   125   11    6  -3.3  -1.8   21.6  70.8    -6.5      M    M

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

           09/04/2015 at 0900 MDT          |       09/04/2015 at 1200 MDT
                                           |
K index... +26.7  LI... +274.6             | K index... +26.8  LI... +273.3
CAPE... 0.0  CIN... -0.6                   | CAPE... +0.8  CIN... -0.6
                                           |
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 -62.3 -80.1  240  42 22  -0.4  -0.2 | -62.3 -80.1  240  44 23   0.0   0.0
 45000 -60.8 -77.4  245  56 29   5.1   2.8 | -60.4 -76.7  240  57 29   5.0   2.8
 40000 -53.1 -63.6  240  69 36   5.8   3.2 | -52.4 -62.3  235  72 37   5.8   3.2
 38000 -49.6 -57.3  235  68 35   5.8   3.2 | -49.0 -56.2  230  71 37   5.8   3.2
 36000 -46.1 -51.0  235  67 34   5.8   3.2 | -45.5 -49.9  225  71 37   5.8   3.2
 34000 -41.5 -42.7  230  62 32   7.1   3.9 | -41.3 -42.3  225  67 35   7.3   4.0
 32000 -37.2 -35.0  225  57 29   7.1   3.9 | -36.9 -34.4  225  62 32   7.4   4.0
 30000 -32.6 -26.7  220  51 26   8.0   4.4 | -32.3 -26.1  220  55 28   8.0   4.4
 29000 -30.2 -22.4  220  48 25   8.0   4.4 | -29.9 -21.8  215  51 26   8.0   4.4
 28000 -27.7 -17.9  215  45 23   7.8   4.3 | -27.4 -17.3  210  47 24   8.1   4.4
 27000 -25.6 -14.1  210  45 23   7.1   3.9 | -24.7 -12.5  210  45 23   7.3   4.0
 26000 -23.6 -10.5  210  44 23   7.1   3.9 | -22.5  -8.5  210  44 23   7.3   4.0
 25000 -21.5  -6.7  205  44 23   7.3   4.0 | -20.4  -4.7  210  43 22   7.4   4.0
 24000 -19.4  -2.9  210  43 22   7.3   4.0 | -18.3  -0.9  205  41 21   7.0   3.8
 23000 -17.2   1.0  210  40 21   7.3   4.0 | -16.3   2.7  205  39 20   7.1   3.9
 22000 -15.1   4.8  215  38 20   7.4   4.1 | -14.2   6.4  205  36 19   7.2   3.9
 21000 -13.1   8.4  215  35 18   6.5   3.6 | -12.4   9.7  205  33 17   6.3   3.4
 20000 -11.2  11.8  220  32 16   6.6   3.6 | -10.6  12.9  210  30 16   6.3   3.5
 19500 -10.2  13.6  220  30 15   6.6   3.6 |  -9.7  14.5  215  29 15   6.3   3.5
 19000  -9.3  15.3  225  28 15   6.3   3.4 |  -8.8  16.2  220  28 14   6.6   3.6
 18500  -8.4  16.9  225  27 14   6.1   3.3 |  -7.8  18.0  220  27 14   6.7   3.7
 18000  -7.5  18.5  225  26 13   6.1   3.3 |  -6.9  19.6  220  25 13   6.7   3.7
 17500  -6.7  19.9  225  24 13   5.6   3.1 |  -5.9  21.4  220  24 12   6.2   3.4
 17000  -5.9  21.4  225  23 12   5.7   3.1 |  -5.0  23.0  225  22 11   6.3   3.5
 16500  -5.1  22.8  225  21 11   5.9   3.2 |  -4.2  24.4  225  21 11   5.8   3.2
 16000  -4.2  24.4  220  19 10   6.1   3.3 |  -3.3  26.1  225  20 10   5.7   3.1
 15500  -2.8  27.0  215  17  9   7.1   3.9 |  -2.5  27.5  225  18  9   6.1   3.3
 15000  -1.8  28.8  215  17  9   7.4   4.0 |  -1.6  29.1  225  17  9   6.9   3.8
 14500  -0.7  30.7  215  16  8   8.3   4.5 |  -0.6  30.9  225  16  8   6.9   3.8
 14000   0.7  33.3  215  15  8   9.0   5.0 |   0.4  32.7  225  15  8   6.4   3.5
 13500   2.0  35.6  215  15  8   9.0   4.9 |   1.3  34.3  225  14  7   6.5   3.5
 13000   3.4  38.1  215  14  7   8.7   4.8 |   2.7  36.9  225  12  6   5.9   3.2
 12500   4.7  40.5  210  13  7   8.6   4.7 |   3.5  38.3  225  11  6   6.1   3.4
 12000   6.0  42.8  210  12  6   8.0   4.4 |   4.5  40.1  220   9  5   7.1   3.9
 11500   7.2  45.0  215  11  6   8.0   4.4 |   5.6  42.1  210   8  4   7.0   3.9
 11000   8.4  47.1  220  10  5   7.6   4.2 |   6.6  43.9  200   7  4   6.7   3.7
 10500   9.6  49.3  225  10  5   5.3   2.9 |   7.6  45.7  190   7  3   4.6   2.5
 10250   9.9  49.8  225   9  5   6.1   3.3 |   7.9  46.2  180   7  3   5.4   3.0
 10000  10.5  50.9  220   9  5   9.9   5.4 |   8.5  47.3  175   6  3   8.8   4.8
  9750  11.2  52.2  220   9  4   9.0   5.0 |   9.1  48.4  170   6  3   8.0   4.4
  9500  11.9  53.4  215   8  4   8.5   4.7 |   9.7  49.5  165   6  3   7.8   4.3
  9250  12.5  54.5  210   8  4   6.7   3.7 |  10.3  50.5  160   6  3   7.1   3.9
  9000  13.0  55.4  205   8  4   7.1   3.9 |  10.8  51.4  155   7  3   7.4   4.1
  8750  13.5  56.3  200   8  4   7.9   4.3 |  11.3  52.3  150   7  3   7.6   4.2
  8500  14.1  57.4  195   8  4   7.6   4.2 |  11.9  53.4  150   7  3   7.7   4.2
  8250  14.6  58.3  195   7  4   7.7   4.2 |  12.5  54.5  145   7  3   8.2   4.5
  8000  15.2  59.4  200   7  4   7.0   3.8 |  13.0  55.4  145   7  4   7.4   4.1
  7750  15.7  60.3  200   8  4   6.6   3.6 |  13.5  56.3  140   7  4   6.6   3.6
  7500  16.1  61.0  200   9  4   6.0   3.3 |  14.0  57.2  140   7  4   6.9   3.8
  7250  16.5  61.7  195  10  5   5.4   3.0 |  14.5  58.1  140   8  4   7.3   4.0
  7000  16.9  62.4  190  11  5   4.9   2.7 |  15.0  59.0  140   9  5   6.3   3.5
  6750  17.2  63.0  185  11  6   3.5   1.9 |  15.4  59.7  140  10  5   6.5   3.6
  6500  17.4  63.3  185  12  6   2.5   1.4 |  16.0  60.8  135  11  6   9.3   5.1
  6250  17.5  63.5  180  10  5   2.4   1.3 |  16.7  62.1  135  11  5  10.7   5.9
  6000  17.6  63.7  175   9  5   1.7   1.0 |  17.4  63.3  135  11  5   9.4   5.2
  5750  17.7  63.9  170   7  4   3.5   1.9 |  18.1  64.6  135  10  5  10.7   5.8
  5500  18.0  64.4  170   6  3   6.6   3.6 |  19.0  66.2  135  10  5  13.0   7.1
  5250  18.4  65.1  165   6  3   5.3   2.9 |  19.9  67.8  135   9  5  11.1   6.1
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/04/2015 at 1500 MDT          |       09/04/2015 at 1800 MDT
                                           |
K index... +28.1  LI... +272.2             | K index... +30.1  LI... +271.0
CAPE... +41.2  CIN... -33.8                | CAPE... +231.4  CIN... -25.5
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.2 -81.8  235  48 25   0.7   0.4 | -62.9 -81.2  230  52 27   0.9   0.5
 45000 -60.4 -76.7  235  61 32   5.2   2.8 | -60.0 -76.0  230  69 35   4.9   2.7
 40000 -52.1 -61.8  230  80 41   5.8   3.2 | -52.1 -61.8  230  97 50   6.5   3.5
 38000 -48.7 -55.7  225  78 40   5.8   3.2 | -48.2 -54.8  230  93 48   6.5   3.6
 36000 -45.2 -49.4  225  76 39   5.8   3.2 | -44.3 -47.7  230  90 46   6.5   3.6
 34000 -40.7 -41.3  220  71 37   7.8   4.3 | -40.2 -40.4  225  81 42   7.0   3.8
 32000 -36.1 -33.0  220  66 34   7.8   4.3 | -36.0 -32.8  225  70 36   7.0   3.9
 30000 -31.5 -24.7  215  58 30   7.7   4.2 | -31.5 -24.7  220  60 31   7.8   4.3
 29000 -29.2 -20.6  215  55 28   7.7   4.2 | -29.2 -20.6  220  56 29   7.8   4.3
 28000 -26.9 -16.4  210  51 26   7.7   4.2 | -26.8 -16.2  215  51 26   7.9   4.3
 27000 -24.1 -11.4  210  51 26   7.6   4.1 | -24.0 -11.2  215  48 25   7.6   4.2
 26000 -21.8  -7.2  210  51 26   7.6   4.2 | -21.8  -7.2  215  47 24   7.7   4.2
 25000 -19.6  -3.3  210  52 27   7.7   4.2 | -19.5  -3.1  215  45 23   7.8   4.3
 24000 -17.6   0.3  210  48 25   6.6   3.6 | -17.5   0.5  215  42 21   6.5   3.6
 23000 -15.7   3.7  215  43 22   6.7   3.7 | -15.6   3.9  215  37 19   6.6   3.6
 22000 -13.7   7.3  215  38 20   6.7   3.7 | -13.7   7.3  215  32 17   6.6   3.6
 21000 -12.0  10.4  215  33 17   6.0   3.3 | -11.9  10.6  215  27 14   6.0   3.3
 20000 -10.2  13.6  220  28 14   6.1   3.3 | -10.2  13.6  215  22 11   6.1   3.3
 19500  -9.3  15.3  220  25 13   6.1   3.3 |  -9.3  15.3  210  20 10   6.1   3.3
 19000  -8.4  16.9  220  23 12   5.7   3.1 |  -8.4  16.9  210  17  9   6.2   3.4
 18500  -7.6  18.3  225  21 11   5.6   3.1 |  -7.5  18.5  215  16  8   6.2   3.4
 18000  -6.8  19.8  225  20 10   5.6   3.1 |  -6.6  20.1  220  15  8   6.2   3.4
 17500  -5.9  21.4  230  19 10   6.3   3.4 |  -5.7  21.7  220  14  7   6.2   3.4
 17000  -5.0  23.0  235  18  9   6.2   3.4 |  -4.8  23.4  220  13  6   6.2   3.4
 16500  -4.1  24.6  235  17  9   6.6   3.6 |  -3.9  25.0  225  12  6   6.5   3.6
 16000  -3.1  26.4  240  17  9   6.7   3.7 |  -2.9  26.8  225  11  6   6.6   3.6
 15500  -2.2  28.0  240  16  8   6.8   3.8 |  -2.0  28.4  230  10  5   6.7   3.7
 15000  -1.2  29.8  240  15  8   7.1   3.9 |  -0.9  30.4  230   9  5   7.2   3.9
 14500  -0.1  31.8  240  14  7   7.1   3.9 |   0.1  32.2  230   9  4   7.2   3.9
 14000   0.9  33.6  235  13  7   7.2   3.9 |   1.1  34.0  230   8  4   7.3   4.0
 13500   1.9  35.4  230  12  6   7.1   3.9 |   2.7  36.9  230   7  3   7.4   4.1
 13000   3.5  38.3  225  10  5   7.4   4.1 |   3.8  38.8  225   6  3   7.8   4.3
 12500   4.6  40.3  220   9  5   7.5   4.1 |   5.0  41.0  215   6  3   7.8   4.3
 12000   5.7  42.3  210   8  4   7.8   4.3 |   6.1  43.0  205   6  3   7.6   4.2
 11500   6.8  44.2  200   8  4   7.8   4.3 |   7.2  45.0  195   6  3   7.6   4.2
 11000   8.0  46.4  195   8  4   8.2   4.5 |   8.1  46.6  185   6  3   6.5   3.5
 10500   9.2  48.6  190   8  4   5.3   2.9 |   9.1  48.4  175   7  3   9.9   5.4
 10250   9.5  49.1  185   8  4   5.9   3.2 |  10.0  50.0  170   7  4  11.7   6.4
 10000  10.2  50.4  185   8  4  10.2   5.6 |  10.6  51.1  170   7  4   8.4   4.6
  9750  10.9  51.6  180   8  4   9.4   5.1 |  11.3  52.3  170   7  4   9.4   5.2
  9500  11.6  52.9  180   8  4   8.5   4.6 |  11.9  53.4  170   7  4   8.7   4.8
  9250  12.1  53.8  175   7  4   7.1   3.9 |  12.5  54.5  170   8  4   8.5   4.7
  9000  12.7  54.9  170   7  4   8.1   4.4 |  13.2  55.8  170   8  4   9.2   5.0
  8750  13.3  55.9  165   7  4   8.4   4.6 |  13.9  57.0  170   8  4   9.5   5.2
  8500  13.9  57.0  165   7  3   8.7   4.8 |  14.6  58.3  170   8  4   9.2   5.0
  8250  14.5  58.1  165   7  3   9.3   5.1 |  15.2  59.4  165   8  4   8.4   4.6
  8000  15.2  59.4  165   6  3   9.6   5.3 |  15.8  60.4  165   9  4   7.4   4.0
  7750  15.9  60.6  160   6  3   9.7   5.3 |  16.3  61.3  165   9  4   6.5   3.6
  7500  16.7  62.1  160   6  3   9.9   5.4 |  16.8  62.2  165   9  5   7.9   4.4
  7250  17.4  63.3  165   6  3  10.3   5.7 |  17.4  63.3  165   9  5   9.6   5.2
  7000  18.2  64.8  165   6  3  10.0   5.5 |  18.1  64.6  170   9  4   9.7   5.3
  6750  18.9  66.0  165   6  3   9.9   5.4 |  18.9  66.0  170   9  4  10.0   5.5
  6500  19.7  67.5  165   6  3  10.6   5.8 |  19.6  67.3  170   9  4  10.2   5.6
  6250  20.5  68.9  165   6  3  11.6   6.3 |  20.4  68.7  170   8  4  10.5   5.7
  6000  21.3  70.3  165   6  3   9.8   5.4 |  21.1  70.0  170   8  4  10.1   5.5
  5750  22.0  71.6  165   5  3  11.2   6.2 |  21.9  71.4  170   8  4   8.9   4.9
  5500  23.0  73.4  165   5  3  15.5   8.5 |  22.5  72.5  170   8  4   8.1   4.5
  5250  24.2  75.6  165   5  3  14.5   8.0 |  23.1  73.6  170   7  4   8.4   4.6
  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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