Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 251239
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0639 MDT Saturday, October 25, 2014

This forecast is for Saturday, October 25, 2014:

If the trigger temperature of 75.5 F/24.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 222 ft/min (1.1 m/s)
   Maximum height of thermals.................. 8415 ft MSL (3576 ft AGL)

Forecast maximum temperature................... 75.0 F/24.3 C
Time of trigger temperature.................... 1445 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7147 ft MSL (2308 ft AGL)
Thermal soaring outlook for Sunday 10/26....... Good

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

Remarks...

Sunrise/Sunset.................... 07:34:17 / 18:23:02 MDT
Total possible sunshine........... 10 hr 48 min 45 sec (648 min 45 sec)
Altitude of sun at 12:58:17 MDT... 38.64 degrees

Upper air data from rawinsonde observation taken on 10/25/2014 at 0600 MDT

Freezing level.................. 14325 ft MSL (9486 ft AGL)
Convective condensation level... 22429 ft MSL (17590 ft AGL)
Lifted condensation level....... 16775 ft MSL (11936 ft AGL)
Lifted index.................... +9.5
K index......................... -10.3

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -69.6 -93.3   250   43   22   5.4   3.0   80.3 176.6    32.5      M    M
 45000  -62.5 -80.5   250   41   21   1.4   0.7   67.8 154.0    27.1      M    M
 40000  -56.3 -69.3   230   45   23   5.9   3.2   53.4 128.2    19.6      M    M
 38000  -52.0 -61.6   225   46   24   7.9   4.3   51.0 123.8    18.5      M    M
 36000  -47.5 -53.5   220   48   25   5.3   2.9   49.2 120.6    17.7      M    M
 34000  -43.1 -45.6   220   47   24   7.9   4.3   47.2 116.9    16.7      M    M
 32000  -38.3 -36.9   210   44   23   7.9   4.4   45.7 114.3    16.1      M    M
 30000  -32.6 -26.7   215   43   22   8.6   4.7   44.8 112.6    15.8      M    M
 29000  -30.0 -22.0   215   39   20   8.6   4.7   44.2 111.5    15.6      M    M
 28000  -27.4 -17.3   220   36   18   8.6   4.7   43.7 110.7    15.4      M    M
 27000  -24.8 -12.6   220   32   17   8.6   4.7   43.3 110.0    15.3      M    M
 26000  -22.3  -8.1   225   29   15   8.6   4.7   43.1 109.5    15.2      M    M
 25000  -19.7  -3.5   220   27   14   8.4   4.6   42.6 108.6    15.0      M    M
 24000  -17.5   0.5   210   23   12   6.8   3.8   41.5 106.7    14.3      M    M
 23000  -15.5   4.1   205   20   10   6.9   3.8   40.4 104.8    13.6      M    M
 22000  -13.4   7.9   195   17    9   6.9   3.8   39.5 103.1    13.0      M    M
 21000  -11.4  11.5   190   18    9   6.9   3.8   38.4 101.2    12.2      M    M
 20000   -9.1  15.6   190   20   10   8.1   4.5   37.7  99.9    11.7      M    M
 19500   -7.9  17.8   200   21   11   8.1   4.4   37.4  99.4    11.5      M    M
 19000   -6.6  20.1   210   22   11   9.7   5.3   37.2  99.0    11.5      M    M
 18500   -5.3  22.5   220   22   12   2.9   1.6   37.0  98.6    11.3      M    M
 18000   -5.5  22.1   230   24   12   1.8   1.0   35.1  95.3     9.8      M    M
 17500   -4.8  23.4   230   24   12   7.2   4.0   34.3  93.8     9.1      M    M
 17000   -4.0  24.8   230   23   12   0.7   0.4   33.5  92.2     8.4      M    M
 16500   -3.3  26.1   230   22   12   5.5   3.0   31.8  89.3     7.0      M    M
 16000   -2.5  27.5   230   22   12   5.4   2.9   31.1  88.0     6.4      M    M
 15500   -1.7  28.9   235   24   13   5.4   2.9   30.3  86.6     5.7      M    M
 15000   -0.9  30.4   235   26   13   5.4   3.0   29.6  85.3     5.1      M    M
 14500   -0.2  31.6   240   23   12   5.3   2.9   28.9  84.0     4.4      M    M
 14000    0.8  33.4   245   21   11   7.8   4.3   28.4  83.1     3.9      M    M
 13500    1.9  35.4   240   19   10   7.5   4.1   28.0  82.4     3.6      M    M
 13000    3.0  37.4   230   17    9   7.5   4.1   27.6  81.7     3.3      M    M
 12500    4.1  39.4   225   15    8   7.5   4.1   27.3  81.1     2.9      M    M
 12000    5.3  41.5   215   14    7   7.6   4.1   26.9  80.5     2.6      M    M
 11500    6.4  43.5   220   15    8   7.6   4.1   26.6  79.8     2.3      M    M
 11000    7.5  45.5   220   15    8   7.5   4.1   26.2  79.2     1.9      M    M
 10500    8.7  47.7   225   16    8   9.7   5.3   26.0  78.8     1.7      M    M
 10250    9.4  48.9   225   15    8   8.8   4.8   26.0  78.7     1.7      M    M
 10000    9.8  49.6   230   15    8   4.3   2.4   25.7  78.3     1.4      M    M
  9750   10.0  50.0   235   14    7   5.4   3.0   25.3  77.5     0.8      M    M
  9500   10.6  51.1   235   13    7   8.2   4.5   25.1  77.2     0.7      M    M
  9250   11.1  52.0   240   13    6   7.5   4.1   24.9  76.9     0.5      M    M
  9000   11.7  53.1   245   12    6   7.7   4.2   24.8  76.6     0.4      M    M
  8750   12.3  54.1   240   11    6   7.7   4.2   24.6  76.3     0.2      M    M
  8500   12.9  55.2   230   10    5   7.4   4.1   24.4  76.0     0.1      M    M
  8250   13.5  56.3   225    9    4   8.4   4.6   24.3  75.7    -0.1    209  1.1
  8000   14.0  57.2   210    8    4   3.5   1.9   24.1  75.3    -0.3    185  0.9
  7750   14.0  57.2   195    9    4  -1.1  -0.6   23.3  73.9    -1.0    178  0.9
  7500   13.9  57.0   180   10    5   0.1   0.1   22.5  72.6    -1.8    172  0.9
  7250   13.9  57.0   170   12    6  -0.2  -0.1   21.8  71.2    -2.5    165  0.8
  7000   13.9  57.0   160   14    7  -0.2  -0.1   21.0  69.8    -3.3    158  0.8
  6750   13.9  57.0   155   14    7  -0.1  -0.0   20.3  68.5    -4.1    152  0.8
  6500   13.8  56.8   150   15    8  -0.4  -0.2   19.5  67.1    -4.8    145  0.7
  6250   13.8  56.8   140   16    8   0.9   0.5   18.8  65.8    -5.6    139  0.7
  6000   14.0  57.2   135   17    9   5.3   2.9   18.3  64.9    -6.1    125  0.6
  5750   14.5  58.1   135   16    8   4.8   2.6   18.0  64.3    -6.4    105  0.5
  5500   14.9  58.8   130   14    7  11.6   6.4   17.7  63.8    -6.7     84  0.4
  5250   15.3  59.5   125   12    6 -15.2  -8.3   17.4  63.3    -7.1     64  0.3
  5000   11.6  52.9   120   10    5 -76.9 -42.2   13.1  55.5   -11.6    169  0.9

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

           10/25/2014 at 0900 MDT          |       10/25/2014 at 1200 MDT
                                           |
K index... +0.1  LI... +3.8                | K index... +8.8  LI... +2.7
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.4
                                           |
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 -69.2 -92.6  250  41 21   4.0   2.2 | -68.8 -91.8  240  48 25   3.4   1.9
 45000 -63.0 -81.4  240  46 24   4.5   2.5 | -63.2 -81.8  235  52 27   4.9   2.7
 40000 -56.0 -68.8  225  50 26   7.4   4.0 | -55.7 -68.3  220  59 30   7.0   3.8
 38000 -51.7 -61.1  220  49 25   7.1   3.9 | -51.6 -60.9  220  58 30   6.8   3.7
 36000 -47.0 -52.6  215  49 25   7.0   3.9 | -47.6 -53.7  215  56 29   6.8   3.7
 34000 -42.5 -44.5  215  46 24   7.4   4.1 | -42.6 -44.7  215  54 28   7.6   4.2
 32000 -38.1 -36.6  210  43 22   7.3   4.0 | -38.0 -36.4  215  53 27   7.6   4.2
 30000 -33.1 -27.6  215  38 20   8.6   4.7 | -33.3 -27.9  215  47 24   7.8   4.3
 29000 -30.5 -22.9  215  36 18   8.6   4.7 | -31.0 -23.8  215  44 23   7.8   4.3
 28000 -27.9 -18.2  220  33 17   8.1   4.5 | -28.6 -19.5  215  41 21   7.8   4.3
 27000 -25.6 -14.1  210  33 17   7.6   4.2 | -26.3 -15.3  215  40 21   7.8   4.3
 26000 -23.3  -9.9  205  32 17   7.6   4.2 | -24.0 -11.2  215  39 20   7.8   4.3
 25000 -21.0  -5.8  200  32 17   7.6   4.2 | -21.6  -6.9  215  39 20   7.8   4.3
 24000 -18.8  -1.8  200  32 16   7.5   4.1 | -19.4  -2.9  215  38 19   7.6   4.2
 23000 -16.5   2.3  200  31 16   7.6   4.2 | -17.1   1.2  215  36 19   7.6   4.2
 22000 -14.3   6.3  205  30 15   7.6   4.2 | -14.8   5.4  215  35 18   7.7   4.2
 21000 -12.2  10.0  210  29 15   6.7   3.7 | -12.9   8.8  215  33 17   6.1   3.3
 20000  -9.7  14.5  215  29 15   6.7   3.7 | -10.6  12.9  215  32 16   6.1   3.3
 19500  -8.7  16.3  220  28 15   6.7   3.7 |  -9.7  14.5  215  31 16   6.1   3.3
 19000  -7.7  18.1  220  28 14   6.6   3.6 |  -8.8  16.2  215  30 15   6.0   3.3
 18500  -6.7  19.9  220  27 14   6.7   3.7 |  -7.9  17.8  215  29 15   6.1   3.3
 18000  -5.7  21.7  225  26 13   6.2   3.4 |  -7.0  19.4  215  27 14   6.2   3.4
 17500  -4.8  23.4  225  25 13   6.0   3.3 |  -6.1  21.0  215  26 14   6.2   3.4
 17000  -3.9  25.0  230  25 13   5.9   3.2 |  -5.2  22.6  220  25 13   6.2   3.4
 16500  -3.1  26.4  230  24 12   5.6   3.1 |  -4.3  24.3  220  25 13   6.2   3.4
 16000  -2.2  28.0  235  23 12   5.6   3.0 |  -3.3  26.1  225  24 12   6.2   3.4
 15500  -1.4  29.5  235  22 11   6.0   3.3 |  -2.4  27.7  225  23 12   6.6   3.6
 15000  -0.5  31.1  235  21 11   6.0   3.3 |  -1.5  29.3  225  22 11   6.6   3.6
 14500   0.4  32.7  235  20 10   6.4   3.5 |  -0.5  31.1  225  21 11   7.3   4.0
 14000   1.3  34.3  235  19 10   6.7   3.7 |   0.6  33.1  225  20 10   7.6   4.2
 13500   2.3  36.1  230  18  9   6.7   3.7 |   1.6  34.9  225  19 10   7.7   4.2
 13000   3.2  37.8  230  17  9   6.7   3.7 |   2.7  36.9  225  18  9   7.8   4.3
 12500   4.1  39.4  225  16  8   7.1   3.9 |   3.7  38.7  220  18  9   8.2   4.5
 12000   5.1  41.2  225  15  8   7.7   4.2 |   5.0  41.0  220  17  9   9.1   5.0
 11500   6.2  43.2  225  13  7   7.8   4.3 |   6.4  43.5  220  16  8   8.9   4.9
 11000   7.3  45.1  220  12  6   8.1   4.5 |   7.7  45.9  220  16  8   8.2   4.5
 10500   8.6  47.5  215  10  5   7.4   4.1 |   8.9  48.0  220  16  8   5.8   3.2
 10250   9.1  48.4  215  10  5   6.7   3.7 |   9.2  48.6  220  16  8   4.8   2.6
 10000   9.6  49.3  210   9  5   8.0   4.4 |   9.8  49.6  220  15  8   9.5   5.2
  9750  10.3  50.5  205   8  4   8.8   4.8 |  10.6  51.1  220  15  8  10.9   6.0
  9500  10.9  51.6  200   8  4   7.9   4.3 |  11.3  52.3  220  15  8   9.0   4.9
  9250  11.5  52.7  195   7  4   6.4   3.5 |  11.9  53.4  215  15  8   6.0   3.3
  9000  12.0  53.6  190   7  4   7.2   3.9 |  12.3  54.1  215  15  8   7.2   3.9
  8750  12.6  54.7  190   8  4   8.6   4.7 |  13.0  55.4  215  14  7   9.2   5.0
  8500  13.2  55.8  185   8  4   7.0   3.9 |  13.6  56.5  210  14  7   7.1   3.9
  8250  13.6  56.5  180   9  4   5.6   3.1 |  14.1  57.4  205  14  7   5.5   3.0
  8000  14.1  57.4  180   9  5   5.8   3.2 |  14.5  58.1  200  13  7   5.3   2.9
  7750  14.5  58.1  175  10  5   5.5   3.0 |  14.8  58.6  195  13  7   4.4   2.4
  7500  14.9  58.8  170  11  6   2.5   1.4 |  15.1  59.2  185  13  7   3.3   1.8
  7250  14.9  58.8  165  12  6   0.2   0.1 |  15.4  59.7  180  12  6   2.7   1.5
  7000  15.0  59.0  165  12  6   1.4   0.8 |  15.6  60.1  175  11  6   2.4   1.3
  6750  15.1  59.2  160  13  7  -0.7  -0.4 |  15.8  60.4  165  10  5   4.8   2.6
  6500  14.9  58.8  155  12  6  -4.9  -2.7 |  16.4  61.5  165   8  4   8.8   4.8
  6250  14.5  58.1  145  11  6  -4.1  -2.3 |  17.1  62.8  165   8  4   9.6   5.3
  6000  14.1  57.4  140  10  5  -9.6  -5.3 |  17.8  64.0  165   7  4   9.0   4.9
  5750  12.9  55.2  130   9  5 -20.6 -11.3 |  18.5  65.3  165   7  3  13.5   7.4
  5500  11.2  52.2  115   7  4 -21.5 -11.8 |  19.9  67.8  165   6  3  21.8  11.9
  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

           10/25/2014 at 1500 MDT          |       10/25/2014 at 1800 MDT
                                           |
K index... +12.9  LI... +2.2               | K index... +12.7  LI... +1.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -31.6
                                           |
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 -67.7 -89.9  240  51 26   3.1   1.7 | -68.4 -91.1  245  52 27   3.5   1.9
 45000 -62.3 -80.1  235  53 27   5.3   2.9 | -62.0 -79.6  240  54 28   5.8   3.2
 40000 -54.2 -65.6  230  50 26   5.7   3.1 | -53.3 -63.9  235  50 26   5.8   3.2
 38000 -50.8 -59.4  225  55 28   5.7   3.1 | -49.8 -57.6  240  48 25   5.8   3.2
 36000 -47.4 -53.3  220  60 31   5.7   3.1 | -46.3 -51.3  245  46 24   5.8   3.2
 34000 -43.4 -46.1  215  62 32   7.1   3.9 | -42.7 -44.9  245  46 24   6.0   3.3
 32000 -38.6 -37.5  215  61 31   7.1   3.9 | -39.1 -38.4  240  47 24   6.0   3.3
 30000 -34.2 -29.6  215  55 28   7.5   4.1 | -35.2 -31.4  235  48 25   5.8   3.2
 29000 -31.9 -25.4  215  52 27   7.5   4.1 | -33.4 -28.1  235  49 25   5.8   3.2
 28000 -29.7 -21.5  220  48 25   7.6   4.1 | -31.7 -25.1  230  49 25   6.3   3.5
 27000 -27.4 -17.3  220  45 23   7.7   4.2 | -29.1 -20.4  230  43 22   9.1   5.0
 26000 -25.1 -13.2  225  41 21   7.7   4.2 | -26.4 -15.5  225  36 19   9.1   5.0
 25000 -22.8  -9.0  230  38 19   7.7   4.2 | -23.7 -10.7  220  29 15   9.2   5.1
 24000 -20.4  -4.7  230  36 18   7.7   4.2 | -21.3  -6.3  220  29 15   7.4   4.1
 23000 -18.1  -0.6  235  34 17   7.7   4.2 | -19.1  -2.4  225  33 17   7.4   4.1
 22000 -15.8   3.6  235  32 16   7.8   4.3 | -16.8   1.8  230  37 19   7.4   4.1
 21000 -13.8   7.2  240  31 16   6.6   3.6 | -14.7   5.5  235  36 19   7.1   3.9
 20000 -11.8  10.8  240  30 15   6.6   3.6 | -12.5   9.5  235  34 18   7.1   3.9
 19500 -10.8  12.6  240  29 15   6.6   3.6 | -11.4  11.5  240  33 17   7.2   3.9
 19000  -9.8  14.4  240  29 15   6.4   3.5 | -10.4  13.3  240  33 17   6.8   3.7
 18500  -8.9  16.0  235  29 15   6.4   3.5 |  -9.4  15.1  240  32 17   6.7   3.7
 18000  -7.9  17.8  235  29 15   6.4   3.5 |  -8.4  16.9  240  32 16   6.7   3.7
 17500  -6.9  19.6  235  29 15   6.9   3.8 |  -7.3  18.9  240  32 16   7.3   4.0
 17000  -5.9  21.4  230  30 15   6.9   3.8 |  -6.3  20.7  240  31 16   7.3   4.0
 16500  -4.9  23.2  230  30 15   7.2   4.0 |  -5.2  22.6  240  31 16   7.5   4.1
 16000  -3.8  25.2  225  30 15   7.3   4.0 |  -4.1  24.6  240  30 16   7.6   4.2
 15500  -2.3  27.9  225  30 15   7.2   3.9 |  -3.0  26.6  240  30 15   7.4   4.1
 15000  -1.2  29.8  225  29 15   7.3   4.0 |  -1.9  28.6  235  29 15   7.1   3.9
 14500  -0.2  31.6  225  29 15   7.1   3.9 |  -0.4  31.3  230  28 14   7.2   3.9
 14000   0.7  33.3  220  28 14   7.1   3.9 |   0.5  32.9  230  27 14   7.3   4.0
 13500   1.7  35.1  220  27 14   7.6   4.2 |   1.5  34.7  225  26 13   8.1   4.5
 13000   2.9  37.2  220  24 13   8.1   4.4 |   2.8  37.0  220  25 13   9.1   5.0
 12500   4.0  39.2  220  22 11   8.5   4.7 |   4.1  39.4  220  25 13   9.1   5.0
 12000   5.4  41.7  215  21 11   9.2   5.1 |   5.5  41.9  215  24 13   9.0   4.9
 11500   6.8  44.2  215  20 10   9.1   5.0 |   6.8  44.2  215  24 12   8.9   4.9
 11000   8.1  46.6  215  18 10   8.7   4.8 |   8.0  46.4  215  23 12   8.4   4.6
 10500   9.5  49.1  210  17  9   5.1   2.8 |   9.3  48.7  210  22 11   4.8   2.6
 10250   9.7  49.5  210  17  9   5.8   3.2 |   9.5  49.1  210  21 11   5.7   3.1
 10000  10.5  50.9  210  16  8  11.0   6.0 |  10.3  50.5  210  21 11  11.1   6.1
  9750  11.2  52.2  210  15  8  10.1   5.5 |  11.0  51.8  210  20 10  10.1   5.6
  9500  11.9  53.4  205  15  8   8.4   4.6 |  11.8  53.2  210  19 10   8.5   4.7
  9250  12.4  54.3  205  14  7   6.5   3.6 |  12.3  54.1  210  18  9   6.4   3.5
  9000  13.0  55.4  205  13  7   8.0   4.4 |  12.8  55.0  210  17  9   8.1   4.5
  8750  13.6  56.5  200  12  6   8.4   4.6 |  13.5  56.3  210  16  8   9.1   5.0
  8500  14.2  57.6  200  11  5   7.8   4.3 |  14.1  57.4  210  15  8   8.1   4.5
  8250  14.8  58.6  200  10  5   7.2   4.0 |  14.7  58.5  210  14  7   7.4   4.0
  8000  15.3  59.5  200   9  4   8.1   4.4 |  15.2  59.4  210  13  7   7.3   4.0
  7750  16.0  60.8  205   8  4   8.9   4.9 |  15.8  60.4  215  12  6   7.1   3.9
  7500  16.6  61.9  205   8  4   9.6   5.3 |  16.3  61.3  220  10  5   7.1   3.9
  7250  17.4  63.3  205   7  4  10.4   5.7 |  16.8  62.2  225   9  5   7.2   3.9
  7000  18.2  64.8  205   7  4   9.4   5.2 |  17.4  63.3  230   9  4   6.8   3.8
  6750  18.8  65.8  205   7  4   9.4   5.2 |  17.9  64.2  235   8  4   6.8   3.7
  6500  19.6  67.3  210   7  4  10.5   5.8 |  18.4  65.1  245   8  4   7.8   4.3
  6250  20.4  68.7  210   7  3  11.0   6.1 |  19.0  66.2  250   7  4   7.7   4.2
  6000  21.2  70.2  210   7  3   9.4   5.2 |  19.6  67.3  260   7  4   9.2   5.0
  5750  21.8  71.2  210   6  3   9.5   5.2 |  20.2  68.4  275   6  3   4.0   2.2
  5500  22.6  72.7  215   6  3  11.5   6.3 |  20.1  68.2  270   5  3  -2.5  -1.4
  5250  23.4  74.1  215   6  3   9.8   5.4 |  20.0  68.0  270   5  2   2.6   1.4
  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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