Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 261250
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0650 MDT Tuesday, August 26, 2014

This forecast is for Tuesday, August 26, 2014:

If the trigger temperature of 79.7 F/26.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7725 ft MSL (2886 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 1300 MDT
Time of overdevelopment........................ 1000 MDT
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................. 6259 ft MSL (1420 ft AGL)
Thermal soaring outlook for Wednesday 08/27.... Poor

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

Remarks...

Sunrise/Sunset.................... 06:37:25 / 19:54:59 MDT
Total possible sunshine........... 13 hr 17 min 35 sec (797 min 35 sec)
Altitude of sun at 13:15:47 MDT... 61.11 degrees

Upper air data from rawinsonde observation taken on 08/26/2014 at 0600 MDT

Freezing level.................. 14543 ft MSL (9704 ft AGL)
Convective condensation level... 14595 ft MSL (9756 ft AGL)
Lifted condensation level....... 13252 ft MSL (8412 ft AGL)
Lifted index.................... -0.1
K index......................... +25.8

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  -63.7 -82.7   225   38   19  -2.1  -1.1   89.7 193.5    37.1      M    M
 45000  -61.0 -77.8   230   68   35   4.9   2.7   68.5 155.4    26.7      M    M
 40000  -55.4 -67.7   240   71   37   9.9   5.5   54.7 130.4    19.4      M    M
 38000  -51.0 -59.8   235   67   35   7.1   3.9   52.5 126.4    18.4      M    M
 36000  -46.1 -51.0   230   64   33   9.4   5.2   51.1 123.9    17.9      M    M
 34000  -40.7 -41.3   230   59   30   8.5   4.7   50.4 122.7    17.8      M    M
 32000  -36.0 -32.8   225   54   28   6.1   3.3   49.0 120.2    17.2      M    M
 30000  -31.6 -24.9   230   48   25   8.2   4.5   46.1 114.9    15.5      M    M
 29000  -29.3 -20.7   230   45   23   7.7   4.2   45.3 113.5    15.1      M    M
 28000  -27.1 -16.8   225   43   22   5.7   3.1   44.3 111.8    14.5      M    M
 27000  -25.5 -13.9   225   41   21   6.2   3.4   42.7 108.9    13.4      M    M
 26000  -23.6 -10.5   220   38   20   6.1   3.4   41.4 106.5    12.5      M    M
 25000  -21.3  -6.3   220   36   18   7.2   3.9   40.6 105.2    11.9      M    M
 24000  -20.0  -4.0   220   34   17   9.2   5.0   38.7 101.6    10.5      M    M
 23000  -18.0  -0.4   220   33   17   6.1   3.4   37.6  99.8     9.7      M    M
 22000  -16.2   2.8   225   33   17   7.4   4.0   36.3  97.3     8.6      M    M
 21000  -14.8   5.4   225   32   17  -4.4  -2.4   34.5  94.1     7.2      M    M
 20000  -12.2  10.0   225   32   16  11.6   6.4   34.3  93.8     7.0      M    M
 19500  -11.0  12.2   225   33   17   7.0   3.8   34.0  93.2     6.7      M    M
 19000  -10.1  13.8   225   33   17   5.8   3.2   33.4  92.2     6.3      M    M
 18500   -9.2  15.4   225   32   17   5.7   3.1   32.7  90.9     5.7      M    M
 18000   -8.4  16.9   225   32   16   7.0   3.8   32.0  89.6     5.1      M    M
 17500   -7.1  19.2   225   32   16   7.3   4.0   31.8  89.3     5.0      M    M
 17000   -5.9  21.4   225   31   16   8.6   4.7   31.4  88.6     4.7      M    M
 16500   -4.2  24.4   225   30   16   7.9   4.4   31.0  87.8     4.3      M    M
 16000   -3.0  26.6   225   30   15   8.0   4.4   30.7  87.3     4.0      M    M
 15500   -1.9  28.6   225   28   15   8.0   4.4   30.4  86.7     3.7      M    M
 15000   -0.8  30.6   225   27   14   7.4   4.1   30.1  86.2     3.4      M    M
 14500    0.3  32.5   220   26   13   6.8   3.7   29.7  85.4     3.0      M    M
 14000    1.5  34.7   220   25   13   8.9   4.9   29.4  84.9     2.8      M    M
 13500    2.7  36.9   215   23   12   7.9   4.3   29.1  84.4     2.6      M    M
 13000    3.8  38.8   215   22   11   8.0   4.4   28.8  83.9     2.3      M    M
 12500    5.0  41.0   225   20   10   8.0   4.4   28.5  83.4     2.0      M    M
 12000    6.2  43.2   235   19   10   8.4   4.6   28.3  82.9     1.7      M    M
 11500    7.4  45.3   245   16    8   8.5   4.7   28.1  82.6     1.5      M    M
 11000    8.7  47.7   255   13    7   8.5   4.7   27.9  82.2     1.3      M    M
 10500    9.9  49.8   240   13    7   8.7   4.8   27.7  81.9     1.1      M    M
 10250   10.6  51.1   235   14    7   9.3   5.1   27.6  81.8     1.1      M    M
 10000   11.3  52.3   230   15    8   9.4   5.2   27.6  81.7     1.1      M    M
  9750   12.0  53.6   230   15    8   9.4   5.2   27.6  81.7     1.0      M    M
  9500   12.7  54.9   235   15    8   9.4   5.2   27.6  81.6     1.0      M    M
  9250   13.4  56.1   235   15    8   9.4   5.2   27.6  81.6     1.0      M    M
  9000   14.1  57.4   240   15    8   9.4   5.2   27.5  81.6     0.9      M    M
  8750   14.7  58.5   240   14    7   9.5   5.2   27.5  81.5     0.9      M    M
  8500   15.4  59.7   235   13    6   9.2   5.0   27.5  81.4     0.9      M    M
  8250   16.1  61.0   230   11    6  10.3   5.6   27.4  81.4     0.8      M    M
  8000   16.8  62.2   225   10    5   5.6   3.1   27.4  81.3     0.8      M    M
  7750   16.9  62.4   205    8    4   1.1   0.6   26.8  80.2     0.2      M    M
  7500   17.0  62.6   175    7    4   2.3   1.3   26.2  79.2    -0.5    152  0.8
  7250   17.1  62.8   150    9    4   2.2   1.2   25.6  78.1    -1.1    141  0.7
  7000   17.3  63.1   135   11    6   1.8   1.0   25.0  77.1    -1.7    130  0.7
  6750   17.4  63.3   125   12    6   3.6   2.0   24.5  76.0    -2.3    119  0.6
  6500   17.7  63.9   125   11    6   6.2   3.4   24.1  75.4    -2.7    101  0.5
  6250   18.2  64.8   120   11    6   6.3   3.4   23.9  75.0    -2.9     80  0.4
  6000   18.7  65.7   115   11    6   6.3   3.4   23.6  74.5    -3.2     59  0.3
  5750   19.1  66.4   115   10    5   6.1   3.4   23.3  74.0    -3.5     38  0.2
  5500   19.6  67.3   110    8    4   6.7   3.7   23.1  73.5    -3.8     17  0.1
  5250   20.0  68.0   105    6    3   4.3   2.3   22.8  73.1    -4.1      M    M
  5000   19.8  67.6   100    5    2  -6.8  -3.7   22.0  71.7    -5.0      M    M

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

           08/26/2014 at 0900 MDT          |       08/26/2014 at 1200 MDT
                                           |
K index... +28.9  LI... -2.9               | K index... +23.8  LI... -3.4
CAPE... +399.7  CIN... -6.6                | CAPE... +458.1  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 -62.9 -81.2  240  35 18   0.6   0.3 | -61.9 -79.4  230  34 17   0.4   0.2
 45000 -60.5 -76.9  240  58 30   4.2   2.3 | -59.5 -75.1  230  58 30   4.5   2.5
 40000 -53.9 -65.0  225  65 33   6.8   3.7 | -52.7 -62.9  225  64 33   5.2   2.9
 38000 -49.9 -57.8  230  60 31   6.7   3.7 | -49.6 -57.3  225  62 32   5.2   2.8
 36000 -45.9 -50.6  230  56 29   6.7   3.7 | -46.5 -51.7  220  60 31   5.2   2.9
 34000 -41.6 -42.9  230  52 27   7.3   4.0 | -41.5 -42.7  225  55 28   8.0   4.4
 32000 -36.7 -34.1  230  48 25   7.2   3.9 | -36.7 -34.1  225  50 26   7.9   4.3
 30000 -32.4 -26.3  225  45 23   7.2   3.9 | -32.4 -26.3  225  43 22   7.2   4.0
 29000 -30.3 -22.5  225  43 22   7.2   3.9 | -30.2 -22.4  220  40 21   7.2   4.0
 28000 -28.1 -18.6  225  42 22   7.3   4.0 | -28.1 -18.6  220  37 19   7.2   4.0
 27000 -26.0 -14.8  225  39 20   7.3   4.0 | -26.0 -14.8  220  36 18   7.2   4.0
 26000 -23.8 -10.8  225  37 19   7.4   4.0 | -23.8 -10.8  220  34 18   7.2   4.0
 25000 -21.6  -6.9  225  35 18   7.5   4.1 | -21.7  -7.1  220  33 17   7.3   4.0
 24000 -19.6  -3.3  225  33 17   6.7   3.6 | -19.6  -3.3  220  31 16   6.8   3.7
 23000 -17.6   0.3  230  33 17   6.7   3.7 | -17.6   0.3  220  29 15   6.8   3.7
 22000 -15.7   3.7  230  32 16   6.7   3.7 | -15.6   3.9  220  27 14   6.8   3.7
 21000 -13.7   7.3  230  31 16   6.6   3.6 | -13.8   7.2  225  26 13   6.1   3.4
 20000 -11.8  10.8  230  30 16   6.6   3.6 | -12.0  10.4  230  25 13   6.1   3.4
 19500 -10.8  12.6  230  30 15   6.6   3.6 | -11.1  12.0  230  24 12   6.1   3.3
 19000  -9.8  14.4  230  30 15   6.9   3.8 |  -9.6  14.7  235  23 12   7.2   3.9
 18500  -8.8  16.2  230  30 15   7.0   3.8 |  -8.6  16.5  235  23 12   7.2   3.9
 18000  -7.2  19.0  230  29 15   7.2   3.9 |  -7.5  18.5  235  23 12   7.3   4.0
 17500  -6.2  20.8  230  29 15   7.2   4.0 |  -6.4  20.5  235  23 12   7.4   4.0
 17000  -5.1  22.8  230  28 14   7.2   4.0 |  -5.3  22.5  235  22 11   7.6   4.2
 16500  -4.1  24.6  230  27 14   7.3   4.0 |  -4.1  24.6  235  22 11   8.4   4.6
 16000  -3.1  26.4  230  27 14   7.4   4.1 |  -2.9  26.8  235  21 11   8.4   4.6
 15500  -2.1  28.2  230  26 13   7.2   4.0 |  -1.7  28.9  235  21 11   7.5   4.1
 15000  -1.1  30.0  225  25 13   7.3   4.0 |  -0.6  30.9  235  20 10   7.6   4.2
 14500  -0.0  32.0  225  23 12   7.7   4.2 |   0.5  32.9  235  19 10   7.4   4.1
 14000   1.0  33.8  225  21 11   7.8   4.3 |   1.6  34.9  235  19 10   7.3   4.0
 13500   2.1  35.8  225  20 10   7.4   4.1 |   2.7  36.9  235  19 10   7.5   4.1
 13000   3.1  37.6  225  18  9   7.2   3.9 |   3.8  38.8  230  19 10   7.7   4.2
 12500   4.1  39.4  225  16  8   7.7   4.2 |   4.9  40.8  230  19 10   7.2   4.0
 12000   5.3  41.5  225  15  8   8.7   4.8 |   5.9  42.6  225  18  9   6.4   3.5
 11500   6.5  43.7  220  13  7   8.4   4.6 |   6.8  44.2  225  16  8   6.6   3.6
 11000   7.7  45.9  220  12  6   7.4   4.1 |   7.8  46.0  220  14  7   7.0   3.8
 10500   8.8  47.8  220  10  5   4.9   2.7 |   8.7  47.7  215  11  6   4.2   2.3
 10250   9.0  48.2  220  10  5   4.8   2.7 |   8.9  48.0  215  10  5   4.8   2.7
 10000   9.6  49.3  220   9  5   9.6   5.3 |   9.5  49.1  215  10  5  10.4   5.7
  9750  10.4  50.7  220   9  5  10.2   5.6 |  10.2  50.4  215   9  5  10.6   5.8
  9500  11.1  52.0  220   8  4   8.4   4.6 |  10.9  51.6  215   8  4   9.4   5.2
  9250  11.6  52.9  220   8  4   5.7   3.1 |  11.4  52.5  215   8  4   7.5   4.1
  9000  12.0  53.6  215   7  4   7.3   4.0 |  12.0  53.6  215   7  4   9.0   4.9
  8750  12.7  54.9  215   7  4   9.2   5.1 |  12.7  54.9  215   7  4  10.6   5.8
  8500  13.3  55.9  210   7  3   7.5   4.1 |  13.4  56.1  215   6  3   9.0   4.9
  8250  13.8  56.8  215   6  3   6.1   3.3 |  14.0  57.2  220   6  3   7.6   4.2
  8000  14.3  57.7  215   6  3   6.6   3.6 |  14.6  58.3  220   5  3   8.3   4.5
  7750  14.8  58.6  215   6  3   6.9   3.8 |  15.2  59.4  225   5  2   8.8   4.8
  7500  15.3  59.5  215   5  3   6.6   3.6 |  15.8  60.4  230   4  2   8.8   4.8
  7250  15.8  60.4  210   5  3   6.2   3.4 |  16.5  61.7  230   4  2   8.7   4.8
  7000  16.3  61.3  205   5  3   6.5   3.6 |  17.1  62.8  235   4  2   9.0   4.9
  6750  16.8  62.2  200   6  3   5.8   3.2 |  17.8  64.0  240   4  2  10.0   5.5
  6500  17.1  62.8  195   6  3   4.5   2.4 |  18.6  65.5  240   4  2  10.5   5.7
  6250  17.5  63.5  185   5  3   4.1   2.3 |  19.3  66.7  245   4  2  10.1   5.6
  6000  17.8  64.0  175   5  3   4.4   2.4 |  20.1  68.2  245   4  2  10.6   5.8
  5750  18.1  64.6  170   6  3   8.0   4.4 |  21.0  69.8  245   4  2  16.1   8.8
  5500  18.9  66.0  165   5  2  13.5   7.4 |  22.5  72.5  250   4  2  24.0  13.2
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/26/2014 at 1500 MDT          |       08/26/2014 at 1800 MDT
                                           |
K index... +27.8  LI... -2.9               | K index... +22.9  LI... -2.1
CAPE... +455.8  CIN... -40.6               | CAPE... +216.3  CIN... -27.1
                                           |
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 -61.8 -79.2  225  36 19   0.0   0.0 | -61.8 -79.2  225  34 18   0.7   0.4
 45000 -59.9 -75.8  225  64 33   4.2   2.3 | -59.6 -75.3  225  63 33   3.0   1.7
 40000 -53.3 -63.9  220  71 37   5.9   3.2 | -54.6 -66.3  215  77 40   6.8   3.7
 38000 -49.8 -57.6  220  68 35   5.8   3.2 | -50.6 -59.1  215  73 37   6.7   3.7
 36000 -46.3 -51.3  220  66 34   5.8   3.2 | -46.6 -51.9  210  69 35   6.7   3.6
 34000 -42.0 -43.6  215  57 29   7.5   4.1 | -42.0 -43.6  210  60 31   7.9   4.3
 32000 -37.0 -34.6  215  45 23   7.3   4.0 | -37.3 -35.1  215  50 26   7.9   4.4
 30000 -32.1 -25.8  215  40 21   8.4   4.6 | -31.5 -24.7  215  46 24   8.9   4.9
 29000 -29.6 -21.3  210  39 20   8.4   4.6 | -28.8 -19.8  215  45 23   9.0   4.9
 28000 -27.1 -16.8  210  37 19   7.4   4.1 | -26.2 -15.2  215  44 22   7.7   4.2
 27000 -25.1 -13.2  210  35 18   6.9   3.8 | -24.1 -11.4  215  43 22   7.2   3.9
 26000 -23.0  -9.4  210  34 18   6.9   3.8 | -22.0  -7.6  215  43 22   7.2   4.0
 25000 -21.0  -5.8  210  33 17   7.0   3.8 | -19.8  -3.6  215  42 22   7.2   3.9
 24000 -18.9  -2.0  210  31 16   7.0   3.9 | -17.9  -0.2  215  41 21   6.2   3.4
 23000 -16.8   1.8  210  29 15   7.0   3.9 | -16.1   3.0  210  39 20   6.2   3.4
 22000 -14.8   5.4  210  27 14   6.9   3.8 | -14.3   6.3  205  37 19   6.2   3.4
 21000 -12.9   8.8  210  25 13   6.4   3.5 | -12.4   9.7  205  33 17   6.3   3.4
 20000 -11.0  12.2  215  21 11   6.4   3.5 | -10.6  12.9  205  28 15   6.3   3.4
 19500 -10.1  13.8  215  20 10   6.5   3.6 |  -9.7  14.5  205  26 13   6.3   3.4
 19000  -9.2  15.4  220  18  9   5.7   3.1 |  -8.8  16.2  205  24 12   6.5   3.6
 18500  -8.3  17.1  225  17  9   5.7   3.1 |  -7.8  18.0  205  21 11   6.6   3.6
 18000  -7.5  18.5  230  16  8   5.7   3.1 |  -6.8  19.8  205  18  9   6.5   3.5
 17500  -6.7  19.9  235  15  8   5.8   3.2 |  -5.9  21.4  205  15  8   6.2   3.4
 17000  -5.8  21.6  240  14  7   5.7   3.1 |  -5.0  23.0  205  12  6   6.2   3.4
 16500  -4.9  23.2  250  13  7   7.4   4.0 |  -4.1  24.6  205  10  5   6.7   3.7
 16000  -3.8  25.2  255  13  7   7.3   4.0 |  -3.1  26.4  210   9  4   6.7   3.7
 15500  -2.7  27.1  260  13  7   8.0   4.4 |  -2.2  28.0  220   7  4   6.9   3.8
 15000  -0.9  30.4  260  13  7   8.3   4.5 |  -1.1  30.0  230   6  3   7.0   3.8
 14500   0.4  32.7  260  13  7   9.1   5.0 |   0.4  32.7  250   5  3   7.3   4.0
 14000   1.8  35.2  255  14  7   9.2   5.0 |   1.5  34.7  260   5  3   7.3   4.0
 13500   3.1  37.6  255  14  7   8.9   4.9 |   2.7  36.9  270   6  3   7.9   4.3
 13000   4.4  39.9  250  14  7   8.7   4.8 |   3.9  39.0  275   6  3   8.2   4.5
 12500   5.6  42.1  250  14  7   8.1   4.5 |   5.2  41.4  275   6  3   8.6   4.7
 12000   6.7  44.1  250  13  7   7.7   4.2 |   6.5  43.7  275   7  3   9.1   5.0
 11500   7.8  46.0  245  12  6   7.6   4.2 |   7.9  46.2  270   7  4   9.0   4.9
 11000   8.9  48.0  240  11  6   7.4   4.0 |   9.2  48.6  270   9  4   8.6   4.7
 10500  10.0  50.0  240  10  5   3.8   2.1 |  10.6  51.1  265  10  5   5.0   2.7
 10250  10.2  50.4  240   9  5   5.5   3.0 |  10.8  51.4  265  10  5   5.8   3.2
 10000  10.9  51.6  240   9  5  11.4   6.3 |  11.5  52.7  265  11  6  11.2   6.2
  9750  11.6  52.9  240   8  4  10.3   5.7 |  12.3  54.1  265  11  6  10.3   5.6
  9500  12.4  54.3  240   8  4   8.5   4.7 |  13.0  55.4  265  12  6   8.7   4.8
  9250  12.9  55.2  245   8  4   7.2   3.9 |  13.5  56.3  265  12  6   7.6   4.2
  9000  13.5  56.3  245   7  4   9.3   5.1 |  14.1  57.4  265  12  6   9.5   5.2
  8750  14.2  57.6  250   7  3   9.5   5.2 |  14.8  58.6  265  12  6   9.7   5.3
  8500  14.8  58.6  255   6  3   8.1   4.5 |  15.4  59.7  265  11  6   9.4   5.1
  8250  15.3  59.5  265   6  3   7.3   4.0 |  16.1  61.0  265  11  6   9.1   5.0
  8000  15.9  60.6  270   5  3   7.2   3.9 |  16.7  62.1  270  10  5   8.9   4.9
  7750  16.4  61.5  280   5  3   7.4   4.0 |  17.4  63.3  270   9  5   8.5   4.6
  7500  17.0  62.6  285   5  3   8.6   4.7 |  17.9  64.2  275   9  5   7.9   4.4
  7250  17.6  63.7  285   5  3   8.7   4.8 |  18.5  65.3  275   8  4   7.7   4.2
  7000  18.2  64.8  285   5  3   9.3   5.1 |  19.0  66.2  280   8  4   7.7   4.2
  6750  18.9  66.0  285   5  3  10.5   5.7 |  19.5  67.1  285   7  4   8.6   4.7
  6500  19.7  67.5  285   5  3  10.5   5.8 |  20.2  68.4  285   7  4   9.4   5.2
  6250  20.5  68.9  285   5  3  10.6   5.8 |  20.8  69.4  285   7  4   9.7   5.3
  6000  21.3  70.3  285   5  3  10.2   5.6 |  21.5  70.7  285   7  4   8.9   4.9
  5750  22.0  71.6  285   5  3  10.7   5.9 |  22.1  71.8  285   7  3   8.4   4.6
  5500  22.9  73.2  285   5  3  11.9   6.5 |  22.7  72.9  285   7  3   8.9   4.9
  5250  23.7  74.7  290   5  3  11.0   6.0 |  23.4  74.1  285   7  3   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 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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