Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 221244
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0644 MDT Thursday, September 22, 2016

This forecast is for Thursday, September 22, 2016:

If the trigger temperature of 78.1 F/25.6 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 540 ft/min (2.7 m/s)
   Maximum height of thermals.................. 13354 ft MSL (8515 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 1300 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 8167 ft MSL (3328 ft AGL)
Thermal soaring outlook for Friday 09/23....... Fair

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

Remarks...

Sunrise/Sunset.................... 07:02:19 / 19:11:47 MDT
Total possible sunshine........... 12 hr 9 min 29 sec (729 min 29 sec)
Altitude of sun at 13:06:34 MDT... 50.81 degrees

Upper air data from rawinsonde observation taken on 09/22/2016 at 0600 MDT

Freezing level.................. 14254 ft MSL (9415 ft AGL)
Convective condensation level... 12685 ft MSL (7846 ft AGL)
Lifted condensation level....... 12845 ft MSL (8006 ft AGL)
Lifted index.................... -0.2
K index......................... +29.0

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  -66.6 -87.9   250   42   22  -3.4  -1.9   83.7 182.7    32.4      M    M
 45000  -60.2 -76.4   240   53   27   7.6   4.2   69.6 157.3    26.0      M    M
 40000  -52.1 -61.8   255   71   37  -2.6  -1.4   58.6 137.5    20.6      M    M
 38000  -50.0 -58.0   240   57   29   9.0   4.9   53.1 127.6    17.3      M    M
 36000  -44.8 -48.6   235   55   28   8.5   4.7   52.2 125.9    17.1      M    M
 34000  -39.4 -38.9   235   49   25   9.1   5.0   51.5 124.8    17.1      M    M
 32000  -34.6 -30.3   230   44   22   7.1   3.9   50.2 122.3    16.5      M    M
 30000  -29.8 -21.6   225   47   24   8.3   4.5   48.0 118.3    15.3      M    M
 29000  -27.6 -17.7   225   50   26   6.3   3.4   46.9 116.5    14.7      M    M
 28000  -25.5 -13.9   225   52   27   7.1   3.9   45.8 114.5    14.0      M    M
 27000  -23.4 -10.1   225   49   25   8.0   4.4   44.8 112.7    13.4      M    M
 26000  -20.9  -5.6   225   46   24   8.3   4.6   44.3 111.7    13.1      M    M
 25000  -18.5  -1.3   225   43   22   8.0   4.4   43.6 110.5    12.7      M    M
 24000  -16.5   2.3   220   41   21   8.3   4.5   42.4 108.4    11.9      M    M
 23000  -14.1   6.6   225   38   20   8.1   4.4   41.8 107.2    11.5      M    M
 22000  -11.7  10.9   225   35   18   7.4   4.1   41.2 106.2    11.2      M    M
 21000   -9.9  14.2   230   35   18   6.0   3.3   39.9 103.9    10.2      M    M
 20000   -8.4  16.9   220   36   18   3.4   1.9   38.4 101.2     8.9      M    M
 19500   -8.1  17.4   210   38   20   2.3   1.3   37.2  98.9     7.8      M    M
 19000   -7.3  18.9   205   41   21  10.0   5.5   36.6  97.9     7.2      M    M
 18500   -5.9  21.4   205   40   21  13.0   7.1   36.5  97.7     7.2      M    M
 18000   -6.4  20.5   210   40   20  -8.6  -4.7   34.4  93.9     5.2      M    M
 17500   -5.3  22.5   210   39   20  10.6   5.8   34.0  93.2     4.8      M    M
 17000   -4.8  23.4   215   38   20   2.0   1.1   33.0  91.4     3.9      M    M
 16500   -3.6  25.5   220   37   19   3.4   1.9   31.7  89.0     3.0      M    M
 16000   -3.8  25.2   220   37   19  -0.3  -0.2   29.9  85.9     1.3      M    M
 15500   -3.1  26.4   220   39   20   7.1   3.9   29.3  84.7     0.6      M    M
 15000   -1.8  28.8   220   41   21   9.5   5.2   29.1  84.5     0.4      M    M
 14500   -0.4  31.3   220   43   22   9.5   5.2   29.1  84.4     0.3      M    M
 14000    0.9  33.6   220   44   23   9.3   5.1   29.1  84.3     0.2      M    M
 13500    2.2  36.0   220   44   23   8.4   4.6   28.9  84.0     0.0      M    M
 13000    3.4  38.1   220   44   23   8.5   4.6   28.7  83.7    -0.2    697  3.5
 12500    4.7  40.5   220   42   22   8.5   4.6   28.5  83.3    -0.4    645  3.3
 12000    5.9  42.6   220   40   21   8.5   4.6   28.3  83.0    -0.6    593  3.0
 11500    7.1  44.8   220   38   20   8.5   4.6   28.1  82.6    -0.8    541  2.7
 11000    8.4  47.1   220   37   19   8.5   4.7   27.9  82.2    -1.0    489  2.5
 10500    9.6  49.3   220   37   19   8.6   4.7   27.7  81.8    -1.3    437  2.2
 10250   10.3  50.5   220   37   19   9.4   5.1   27.6  81.7    -1.4    410  2.1
 10000   10.9  51.6   215   35   18   8.8   4.8   27.6  81.6    -1.4    383  1.9
  9750   11.5  52.7   210   34   17   8.1   4.5   27.4  81.4    -1.6    358  1.8
  9500   12.1  53.8   205   33   17   8.3   4.6   27.3  81.2    -1.7    333  1.7
  9250   12.7  54.9   200   32   16   8.3   4.6   27.2  81.0    -1.9    308  1.6
  9000   13.3  55.9   195   31   16   8.2   4.5   27.1  80.8    -2.0    283  1.4
  8750   13.9  57.0   195   31   16   8.9   4.9   27.0  80.6    -2.1    258  1.3
  8500   14.5  58.1   195   30   15   6.2   3.4   26.9  80.4    -2.3    233  1.2
  8250   14.7  58.5   190   30   15   2.3   1.3   26.4  79.6    -2.7    218  1.1
  8000   14.9  58.8   190   29   15   2.1   1.1   25.8  78.5    -3.3    205  1.0
  7750   15.1  59.2   185   27   14   6.0   3.3   25.3  77.6    -3.8    191  1.0
  7500   15.7  60.3   180   25   13   8.9   4.9   25.2  77.4    -3.9    165  0.8
  7250   16.3  61.3   175   24   12   8.1   4.4   25.1  77.2    -4.0    139  0.7
  7000   17.0  62.6   170   22   11   8.4   4.6   25.0  77.0    -4.2    113  0.6
  6750   17.6  63.7   170   23   12   8.0   4.4   24.9  76.8    -4.3     88  0.4
  6500   18.2  64.8   170   24   12   9.0   4.9   24.8  76.6    -4.4     62  0.3
  6250   18.8  65.8   170   25   13   5.5   3.0   24.7  76.4    -4.5     36  0.2
  6000   18.9  66.0   170   26   13  -0.8  -0.4   24.1  75.3    -5.2     26  0.1
  5750   18.7  65.7   165   22   11  -1.2  -0.7   23.2  73.8    -6.1     23  0.1
  5500   18.5  65.3   160   17    9  -5.9  -3.2   22.3  72.2    -7.0     23  0.1
  5250   17.8  64.0   145   13    7  -8.2  -4.5   20.9  69.7    -8.5     36  0.2
  5000   17.5  63.5   125   10    5   2.1   1.1   19.9  67.9    -9.5     37  0.2

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

           09/22/2016 at 0900 MDT          |       09/22/2016 at 1200 MDT
                                           |
K index... +29.8  LI... +270.6             | K index... +14.0  LI... +270.5
CAPE... +317.7  CIN... -13.5               | CAPE... +527.4  CIN... M
                                           |
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 -66.6 -87.9  235  38 20   2.5   1.3 | -66.1 -87.0  230  43 22   2.2   1.2
 45000 -61.3 -78.3  240  57 29   5.8   3.2 | -61.0 -77.8  240  56 29   6.0   3.3
 40000 -52.3 -62.1  245  65 33   7.1   3.9 | -51.8 -61.2  240  70 36   7.0   3.8
 38000 -48.1 -54.6  240  61 31   7.1   3.9 | -47.6 -53.7  235  68 35   7.0   3.8
 36000 -43.8 -46.8  240  57 30   7.1   3.9 | -43.4 -46.1  230  66 34   7.0   3.8
 34000 -39.4 -38.9  235  56 29   7.4   4.0 | -39.1 -38.4  225  65 34   7.1   3.9
 32000 -34.4 -29.9  230  54 28   7.3   4.0 | -34.3 -29.7  225  64 33   7.1   3.9
 30000 -30.0 -22.0  235  54 28   7.4   4.1 | -30.2 -22.4  220  62 32   6.8   3.7
 29000 -27.8 -18.0  235  54 28   7.4   4.1 | -28.2 -18.8  220  60 31   6.8   3.7
 28000 -25.5 -13.9  235  54 28   7.5   4.1 | -26.1 -15.0  220  59 30   7.2   4.0
 27000 -23.2  -9.8  235  53 27   7.7   4.2 | -23.7 -10.7  215  56 29   8.3   4.5
 26000 -20.9  -5.6  230  52 27   7.7   4.2 | -21.2  -6.2  210  53 27   8.3   4.5
 25000 -18.6  -1.5  230  50 26   7.7   4.2 | -18.7  -1.7  210  51 26   8.3   4.6
 24000 -16.3   2.7  225  48 25   7.7   4.2 | -16.2   2.8  205  47 24   8.2   4.5
 23000 -14.0   6.8  225  45 23   7.8   4.3 | -13.8   7.2  200  42 22   8.2   4.5
 22000 -11.7  10.9  220  42 22   8.2   4.5 | -11.3  11.7  195  37 19   8.6   4.7
 21000 -10.2  13.6  220  38 19   4.4   2.4 |  -9.7  14.5  195  37 19   4.3   2.4
 20000  -9.0  15.8  215  32 17   4.6   2.5 |  -8.5  16.7  200  39 20   4.5   2.5
 19500  -8.4  16.9  210  30 15   4.8   2.7 |  -7.9  17.8  205  40 20   4.7   2.6
 19000  -7.8  18.0  210  28 14   5.6   3.1 |  -7.3  18.9  205  41 21   5.2   2.8
 18500  -6.9  19.6  210  28 15   6.3   3.4 |  -6.5  20.3  205  40 21   5.7   3.1
 18000  -6.0  21.2  215  29 15   6.5   3.5 |  -5.7  21.7  205  40 21   5.7   3.1
 17500  -5.1  22.8  215  30 16   4.9   2.7 |  -4.8  23.4  205  40 20   6.5   3.5
 17000  -4.4  24.1  215  31 16   5.0   2.8 |  -3.8  25.2  210  40 20   6.4   3.5
 16500  -3.7  25.3  215  31 16   5.3   2.9 |  -2.8  27.0  210  40 20   5.3   2.9
 16000  -2.9  26.8  215  31 16   5.6   3.1 |  -2.1  28.2  210  40 20   4.1   2.2
 15500  -2.1  28.2  220  31 16   5.8   3.2 |  -1.3  29.7  210  40 21   4.2   2.3
 15000  -0.6  30.9  220  32 16   7.0   3.8 |  -0.2  31.6  210  40 21   5.5   3.0
 14500   0.4  32.7  220  32 17   7.0   3.8 |   0.7  33.3  210  40 21   5.6   3.0
 14000   1.5  34.7  220  33 17   7.0   3.9 |   1.4  34.5  210  40 21   5.7   3.1
 13500   2.5  36.5  220  35 18   7.0   3.8 |   2.2  36.0  210  40 21   6.0   3.3
 13000   3.5  38.3  220  36 18   6.9   3.8 |   3.1  37.6  210  40 20   7.8   4.3
 12500   4.4  39.9  220  37 19   6.9   3.8 |   4.1  39.4  210  39 20   8.0   4.4
 12000   5.5  41.9  220  37 19   7.7   4.2 |   5.0  41.0  210  38 19   7.5   4.1
 11500   6.5  43.7  215  36 18   7.7   4.2 |   5.9  42.6  205  35 18   8.1   4.4
 11000   7.6  45.7  215  36 18   6.9   3.8 |   6.9  44.4  205  33 17   7.8   4.3
 10500   8.5  47.3  210  36 19   9.6   5.3 |   8.0  46.4  205  30 16   9.5   5.2
 10250   9.3  48.7  210  37 19  10.0   5.5 |   8.8  47.8  205  29 15  11.2   6.1
 10000   9.9  49.8  210  36 19   6.7   3.7 |   9.5  49.1  205  29 15  10.0   5.5
  9750  10.4  50.7  210  36 18   7.7   4.2 |  10.3  50.5  205  29 15  10.1   5.5
  9500  10.9  51.6  205  35 18   7.3   4.0 |  11.0  51.8  205  29 15  10.1   5.5
  9250  11.4  52.5  205  35 18   7.5   4.1 |  11.8  53.2  200  28 15   9.8   5.4
  9000  12.0  53.6  205  34 18   8.6   4.7 |  12.5  54.5  200  28 15   9.8   5.4
  8750  12.6  54.7  205  34 17   9.1   5.0 |  13.2  55.8  200  28 14  10.0   5.5
  8500  13.3  55.9  200  33 17   9.1   5.0 |  14.0  57.2  200  28 14   9.9   5.5
  8250  13.9  57.0  200  33 17   9.9   5.4 |  14.7  58.5  200  27 14  10.6   5.8
  8000  14.7  58.5  200  33 17   9.2   5.0 |  15.5  59.9  200  27 14  10.3   5.6
  7750  15.3  59.5  200  32 17   8.4   4.6 |  16.2  61.2  200  27 14   9.6   5.2
  7500  15.9  60.6  195  32 16   7.9   4.3 |  17.0  62.6  200  26 14  10.0   5.5
  7250  16.4  61.5  195  31 16   7.0   3.9 |  17.7  63.9  200  26 13  10.9   6.0
  7000  16.9  62.4  190  29 15   5.8   3.2 |  18.5  65.3  200  26 13  10.3   5.7
  6750  17.3  63.1  185  27 14   4.6   2.5 |  19.2  66.6  200  25 13   8.5   4.7
  6500  17.6  63.7  180  25 13   2.2   1.2 |  19.9  67.8  200  25 13  10.1   5.5
  6250  17.6  63.7  175  22 11   0.1   0.1 |  20.8  69.4  200  24 12  12.0   6.6
  6000  17.6  63.7  170  19 10   0.8   0.4 |  21.6  70.9  200  23 12  11.3   6.2
  5750  17.8  64.0  165  16  8   3.2   1.7 |  22.4  72.3  200  21 11  11.0   6.1
  5500  18.1  64.6  160  14  7   6.5   3.5 |  23.3  73.9  200  20 10  12.9   7.1
  5250  18.6  65.5  160  13  7   6.7   3.7 |  24.3  75.7  200  19 10  15.2   8.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/22/2016 at 1500 MDT          |       09/22/2016 at 1800 MDT
                                           |
K index... +14.5  LI... +272.0             | K index... +31.2  LI... +271.2
CAPE... +240.0  CIN... -15.3               | CAPE... +190.5  CIN... -32.3
                                           |
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  230  42 22   2.2   1.2 | -65.0 -85.0  215  44 22   1.7   0.9
 45000 -61.1 -78.0  235  63 32   6.0   3.3 | -60.6 -77.1  225  69 36   5.9   3.3
 40000 -51.9 -61.4  230  76 39   7.0   3.8 | -51.7 -61.1  225  84 43   6.4   3.5
 38000 -47.8 -54.0  225  74 38   6.9   3.8 | -47.9 -54.2  220  82 42   6.4   3.5
 36000 -43.6 -46.5  220  72 37   6.9   3.8 | -44.1 -47.4  215  81 42   6.4   3.5
 34000 -39.5 -39.1  220  70 36   6.8   3.7 | -39.9 -39.8  215  79 40   7.2   4.0
 32000 -35.4 -31.7  215  68 35   6.8   3.7 | -35.5 -31.9  210  76 39   7.2   4.0
 30000 -30.4 -22.7  215  65 33   7.6   4.2 | -31.0 -23.8  210  73 37   7.8   4.3
 29000 -28.1 -18.6  210  64 33   7.6   4.2 | -28.0 -18.4  210  70 36   7.8   4.3
 28000 -25.9 -14.6  210  62 32   7.8   4.3 | -25.7 -14.3  210  68 35   7.7   4.2
 27000 -23.4 -10.1  205  59 30   8.3   4.5 | -23.6 -10.5  210  66 34   6.9   3.8
 26000 -20.9  -5.6  205  55 28   8.3   4.5 | -21.5  -6.7  210  63 32   6.9   3.8
 25000 -18.5  -1.3  200  51 26   8.3   4.6 | -19.5  -3.1  210  60 31   6.9   3.8
 24000 -16.1   3.0  200  47 24   7.5   4.1 | -17.4   0.7  210  57 29   7.0   3.8
 23000 -13.9   7.0  200  43 22   7.5   4.1 | -15.3   4.5  210  55 28   7.0   3.9
 22000 -11.6  11.1  205  39 20   7.7   4.2 | -13.2   8.2  210  52 27   7.1   3.9
 21000  -9.9  14.2  205  40 20   5.1   2.8 | -11.5  11.3  210  50 26   5.3   2.9
 20000  -8.4  16.9  210  44 23   5.3   2.9 | -10.0  14.0  210  48 25   5.4   2.9
 19500  -7.7  18.1  210  46 24   5.5   3.0 |  -9.3  15.3  210  47 24   5.4   3.0
 19000  -6.9  19.6  215  48 25   5.4   2.9 |  -8.5  16.7  210  46 24   5.4   2.9
 18500  -6.3  20.7  215  48 25   4.7   2.6 |  -7.9  17.8  205  46 24   4.8   2.6
 18000  -5.6  21.9  215  48 25   4.8   2.6 |  -7.2  19.0  205  46 24   4.8   2.6
 17500  -4.8  23.4  215  48 25   4.4   2.4 |  -6.5  20.3  205  46 23   6.5   3.5
 17000  -4.0  24.8  210  48 25   4.7   2.6 |  -5.5  22.1  200  46 24   6.7   3.7
 16500  -3.2  26.2  210  47 24   4.6   2.5 |  -4.5  23.9  200  47 24   6.6   3.6
 16000  -2.6  27.3  210  47 24   4.1   2.2 |  -3.6  25.5  200  47 24   6.3   3.4
 15500  -2.0  28.4  210  47 24   4.0   2.2 |  -2.7  27.1  195  47 24   6.2   3.4
 15000  -1.2  29.8  210  46 24   6.5   3.6 |  -1.8  28.8  195  46 24   6.7   3.7
 14500   0.0  32.0  210  44 23   6.9   3.8 |  -0.9  30.4  195  44 23   6.6   3.6
 14000   1.0  33.8  205  42 22   7.6   4.2 |   0.8  33.4  195  41 21   9.0   4.9
 13500   1.9  35.4  205  39 20   8.1   4.4 |   2.0  35.6  200  39 20   8.8   4.8
 13000   3.0  37.4  200  37 19   8.7   4.8 |   3.4  38.1  200  37 19   9.3   5.1
 12500   4.1  39.4  200  34 18   8.7   4.8 |   4.7  40.5  200  36 18   9.2   5.0
 12000   5.4  41.7  200  33 17   9.9   5.4 |   6.1  43.0  200  35 18   9.8   5.4
 11500   6.8  44.2  200  32 16   9.9   5.4 |   7.6  45.7  200  34 17   9.9   5.4
 11000   8.2  46.8  195  31 16   8.7   4.8 |   9.0  48.2  200  33 17   8.8   4.8
 10500   9.5  49.1  195  30 16  10.0   5.5 |  10.2  50.4  205  32 16   9.6   5.2
 10250  10.3  50.5  195  30 16  11.4   6.2 |  11.0  51.8  205  31 16  10.7   5.9
 10000  11.1  52.0  195  30 16  10.2   5.6 |  11.8  53.2  205  30 16   9.5   5.2
  9750  11.9  53.4  195  30 15  10.0   5.5 |  12.4  54.3  210  30 15   8.9   4.9
  9500  12.6  54.7  195  30 15  10.2   5.6 |  13.1  55.6  210  29 15   9.3   5.1
  9250  13.4  56.1  195  30 15   9.8   5.4 |  13.8  56.8  210  28 14   8.3   4.5
  9000  14.1  57.4  195  29 15   9.7   5.3 |  14.3  57.7  215  27 14   7.5   4.1
  8750  14.8  58.6  195  29 15  10.0   5.5 |  14.9  58.8  215  26 14   8.0   4.4
  8500  15.6  60.1  195  29 15   9.7   5.3 |  15.4  59.7  220  25 13   7.7   4.2
  8250  16.3  61.3  195  29 15  11.4   6.2 |  16.0  60.8  225  25 13   8.7   4.8
  8000  17.2  63.0  195  28 15  10.7   5.9 |  16.7  62.1  225  24 12   8.5   4.7
  7750  17.9  64.2  195  28 14   8.7   4.8 |  17.2  63.0  230  23 12   7.4   4.1
  7500  18.6  65.5  195  28 14   9.4   5.1 |  17.8  64.0  230  23 12   7.7   4.2
  7250  19.3  66.7  195  28 14  10.7   5.9 |  18.3  64.9  235  22 11   8.0   4.4
  7000  20.1  68.2  195  27 14  10.8   5.9 |  18.9  66.0  235  22 11   8.8   4.8
  6750  20.9  69.6  195  27 14   9.4   5.2 |  19.6  67.3  240  21 11   9.2   5.0
  6500  21.6  70.9  195  26 14  10.2   5.6 |  20.3  68.5  240  20 10   9.2   5.1
  6250  22.4  72.3  195  26 13  11.2   6.2 |  21.0  69.8  245  20 10   9.4   5.2
  6000  23.2  73.8  195  25 13  11.6   6.4 |  21.7  71.1  245  18 10   9.5   5.2
  5750  24.1  75.4  195  23 12  11.8   6.5 |  22.4  72.3  245  17  9  10.5   5.7
  5500  25.0  77.0  195  21 11  13.2   7.2 |  23.2  73.8  250  15  8   8.4   4.6
  5250  26.1  79.0  195  21 11  15.2   8.4 |  23.6  74.5  245  15  8   2.7   1.5
  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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