Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 241243
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0643 MDT Friday, October 24, 2014

This forecast is for Friday, October 24, 2014:

If the trigger temperature of 72.4 F/22.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 416 ft/min (2.1 m/s)
   Maximum height of thermals.................. 10457 ft MSL (5618 ft AGL)

Forecast maximum temperature................... 75.0 F/24.3 C
Time of trigger temperature.................... 1345 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................. 6767 ft MSL (1928 ft AGL)
Thermal soaring outlook for Saturday 10/25..... Good

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

Remarks... Generally light surface winds today. Breezy southerly surface winds
           on Saturday.

Sunrise/Sunset.................... 07:33:13 / 18:24:20 MDT
Total possible sunshine........... 10 hr 51 min 8 sec (651 min 8 sec)
Altitude of sun at 12:58:23 MDT... 38.99 degrees

Upper air data from rawinsonde observation taken on 10/24/2014 at 0600 MDT

Freezing level.................. 15934 ft MSL (11095 ft AGL)
Convective condensation level... 19729 ft MSL (14890 ft AGL)
Lifted condensation level....... 15392 ft MSL (10552 ft AGL)
Lifted index.................... +5.9
K index......................... -11.4

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  -69.5 -93.1   300   42   22   7.2   4.0   80.5 176.8    32.6      M    M
 45000  -65.3 -85.5   270   37   19   9.0   4.9   62.9 145.2    24.1      M    M
 40000  -56.5 -69.7   290   46   24   7.0   3.9   53.5 128.3    19.6      M    M
 38000  -52.2 -62.0   285   50   26   7.5   4.1   51.3 124.3    18.7      M    M
 36000  -47.7 -53.9   290   43   22   8.6   4.7   49.3 120.7    17.8      M    M
 34000  -42.4 -44.3   280   33   17   9.0   5.0   47.5 117.5    17.0      M    M
 32000  -37.0 -34.6   275   35   18   7.0   3.8   46.9 116.3    16.9      M    M
 30000  -31.9 -25.4   275   38   20   8.5   4.6   45.9 114.6    16.6      M    M
 29000  -29.4 -20.9   275   40   21   8.5   4.6   45.4 113.7    16.5      M    M
 28000  -26.9 -16.4   275   36   18   8.5   4.7   44.9 112.7    16.2      M    M
 27000  -24.4 -11.9   280   32   16   7.7   4.3   44.2 111.6    15.9      M    M
 26000  -22.7  -8.9   270   31   16   3.4   1.9   42.8 109.0    15.0      M    M
 25000  -21.5  -6.7   260   31   16   5.9   3.2   40.6 105.1    13.3      M    M
 24000  -19.9  -3.8   260   35   18   5.7   3.1   39.0 102.3    12.2      M    M
 23000  -17.6   0.3   260   33   17   8.3   4.5   38.3 100.9    11.7      M    M
 22000  -14.9   5.2   260   31   16   8.8   4.8   38.0 100.4    11.6      M    M
 21000  -12.8   9.0   260   29   15   8.0   4.4   37.1  98.7    10.9      M    M
 20000  -10.5  13.1   260   27   14   7.9   4.3   36.4  97.6    10.4      M    M
 19500   -9.3  15.3   265   27   14   7.7   4.2   36.1  97.0    10.2      M    M
 19000   -8.1  17.4   265   27   14   8.8   4.8   35.8  96.4    10.0      M    M
 18500   -6.1  21.0   270   27   14   8.9   4.9   35.6  96.0     9.8      M    M
 18000   -4.8  23.4   275   27   14   8.9   4.9   35.4  95.8     9.8      M    M
 17500   -3.5  25.7   275   28   14   8.4   4.6   35.3  95.6     9.7      M    M
 17000   -2.2  28.0   280   28   14   7.4   4.0   35.0  94.9     9.5      M    M
 16500   -1.1  30.0   275   27   14   7.2   3.9   34.5  94.1     9.3      M    M
 16000    0.0  32.0   270   27   14   7.2   4.0   34.1  93.4     9.0      M    M
 15500    1.2  34.2   265   27   14   6.0   3.3   33.7  92.7     8.7      M    M
 15000    1.6  34.9   265   26   14   1.7   0.9   32.6  90.6     7.7      M    M
 14500    1.9  35.4   270   23   12   1.9   1.1   31.2  88.2     6.5      M    M
 14000    2.1  35.8   275   20   10   2.1   1.2   30.0  85.9     5.4      M    M
 13500    2.4  36.3   265   19   10   3.3   1.8   28.7  83.6     4.2      M    M
 13000    3.2  37.8   255   18    9   7.3   4.0   28.1  82.5     3.6      M    M
 12500    4.0  39.2   245   18    9   3.3   1.8   27.3  81.2     2.9      M    M
 12000    4.8  40.6   235   19   10   7.3   4.0   26.7  80.0     2.2      M    M
 11500    5.8  42.4   235   19   10   6.8   3.7   26.2  79.1     1.8      M    M
 11000    6.8  44.2   240   18    9   5.0   2.7   25.7  78.3     1.4      M    M
 10500    7.0  44.6   240   18    9   1.2   0.6   24.4  76.0     0.1      M    M
 10250    7.1  44.8   240   18    9   2.7   1.5   23.8  74.9    -0.5    407  2.1
 10000    7.4  45.3   240   17    9   6.7   3.7   23.4  74.1    -1.0    392  2.0
  9750    8.0  46.4   240   17    9   9.2   5.0   23.3  73.9    -1.1    365  1.9
  9500    8.7  47.7   240   16    8   8.5   4.7   23.2  73.8    -1.2    339  1.7
  9250    9.3  48.7   240   16    8   8.7   4.8   23.2  73.7    -1.2    312  1.6
  9000    9.9  49.8   240   15    8   8.7   4.8   23.1  73.6    -1.3    285  1.4
  8750   10.6  51.1   240   14    7   8.7   4.8   23.0  73.4    -1.4    258  1.3
  8500   11.2  52.2   240   13    7   8.7   4.8   22.9  73.2    -1.5    232  1.2
  8250   11.9  53.4   240   11    6   8.7   4.8   22.8  73.1    -1.6    205  1.0
  8000   12.5  54.5   240   10    5   8.7   4.8   22.8  73.0    -1.7    178  0.9
  7750   13.2  55.8   225    9    5   8.7   4.8   22.7  72.8    -1.8    152  0.8
  7500   13.8  56.8   205    9    4   8.5   4.7   22.6  72.6    -1.9    125  0.6
  7250   14.4  57.9   185   10    5   9.2   5.1   22.5  72.5    -2.0     98  0.5
  7000   15.1  59.2   170   11    6   6.6   3.6   22.4  72.3    -2.1     72  0.4
  6750   15.2  59.4   160   13    7  -5.0  -2.8   21.8  71.2    -2.7     62  0.3
  6500   14.3  57.7   155   15    8 -14.1  -7.7   20.2  68.4    -4.4     81  0.4
  6250   13.2  55.8   155   17    9 -10.2  -5.6   18.5  65.2    -6.1    105  0.5
  6000   12.8  55.0   150   18   10   1.1   0.6   17.4  63.2    -7.3    109  0.6
  5750   13.1  55.6   145   17    9   3.8   2.1   16.9  62.5    -7.8     94  0.5
  5500   13.4  56.1   140   14    7   8.3   4.5   16.5  61.7    -8.3     79  0.4
  5250   13.3  55.9   135   11    5 -25.7 -14.1   15.7  60.3    -9.1     74  0.4
  5000    9.0  48.2   120    8    4 -77.8 -42.7   10.7  51.3   -14.1    195  1.0

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

           10/24/2014 at 0900 MDT          |       10/24/2014 at 1200 MDT
                                           |
K index... +1.5  LI... +6.4                | K index... -2.2  LI... +6.3
CAPE... 0.0  CIN... -1.3                   | CAPE... 0.0  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 -69.7 -93.5  295  42 22   2.2   1.2 | -70.1 -94.2  280  38 20   2.0   1.1
 45000 -65.0 -85.0  295  45 23   6.0   3.3 | -65.4 -85.7  280  40 20   6.4   3.5
 40000 -55.9 -68.6  280  44 22   7.6   4.2 | -55.6 -68.1  270  40 21   7.1   3.9
 38000 -51.4 -60.5  285  44 23   7.5   4.1 | -51.4 -60.5  275  41 21   7.1   3.9
 36000 -46.9 -52.4  285  44 23   7.5   4.1 | -46.6 -51.9  285  43 22   7.1   3.9
 34000 -41.6 -42.9  285  44 23   7.9   4.3 | -41.7 -43.1  285  44 23   8.2   4.5
 32000 -36.8 -34.2  285  44 23   7.8   4.3 | -36.8 -34.2  280  45 23   8.2   4.5
 30000 -31.9 -25.4  290  43 22   8.4   4.6 | -31.7 -25.1  280  43 22   8.5   4.7
 29000 -29.4 -20.9  290  43 22   8.4   4.6 | -29.2 -20.6  280  42 21   8.5   4.7
 28000 -26.9 -16.4  290  43 22   8.0   4.4 | -26.6 -15.9  280  41 21   8.5   4.7
 27000 -24.5 -12.1  285  40 20   7.8   4.3 | -24.0 -11.2  280  39 20   8.6   4.7
 26000 -22.2  -8.0  280  37 19   7.8   4.3 | -21.4  -6.5  280  38 19   8.6   4.7
 25000 -19.9  -3.8  275  34 18   8.0   4.4 | -18.9  -2.0  275  36 19   8.6   4.7
 24000 -18.0  -0.4  270  32 16   5.9   3.3 | -17.0   1.4  270  34 17   5.8   3.2
 23000 -16.2   2.8  260  29 15   6.0   3.3 | -15.2   4.6  260  32 17   5.8   3.2
 22000 -14.4   6.1  250  27 14   6.1   3.3 | -13.5   7.7  250  32 16   5.9   3.2
 21000 -12.2  10.0  250  27 14   7.6   4.2 | -11.5  11.3  245  32 16   6.6   3.6
 20000  -9.4  15.1  250  27 14   7.6   4.2 |  -9.1  15.6  240  32 16   6.6   3.6
 19500  -8.3  17.1  250  27 14   7.7   4.2 |  -8.1  17.4  240  32 17   6.7   3.7
 19000  -7.2  19.0  250  27 14   7.7   4.2 |  -7.1  19.2  240  32 16   6.7   3.7
 18500  -6.0  21.2  250  27 14   7.8   4.3 |  -6.1  21.0  240  31 16   6.7   3.7
 18000  -4.9  23.2  250  27 14   7.0   3.9 |  -5.2  22.6  240  31 16   6.1   3.3
 17500  -3.8  25.2  250  26 13   6.8   3.7 |  -4.3  24.3  245  29 15   5.9   3.2
 17000  -2.8  27.0  250  25 13   6.4   3.5 |  -3.4  25.9  245  28 15   5.7   3.1
 16500  -2.0  28.4  250  23 12   4.8   2.6 |  -2.6  27.3  245  27 14   5.1   2.8
 16000  -1.3  29.7  255  22 11   5.0   2.7 |  -1.8  28.8  250  25 13   5.2   2.9
 15500  -0.6  30.9  255  20 11   4.3   2.4 |  -1.1  30.0  250  23 12   4.8   2.6
 15000  -0.0  32.0  255  19 10   4.3   2.4 |  -0.4  31.3  255  21 11   4.8   2.6
 14500   0.6  33.1  260  19 10   5.0   2.7 |   0.3  32.5  255  20 10   5.7   3.1
 14000   1.4  34.5  260  18  9   5.2   2.9 |   1.2  34.2  255  19 10   6.0   3.3
 13500   2.2  36.0  260  18  9   5.7   3.1 |   2.1  35.8  260  17  9   6.4   3.5
 13000   3.1  37.6  260  18  9   6.3   3.5 |   3.1  37.6  260  17  9   6.8   3.7
 12500   4.0  39.2  260  18  9   6.6   3.6 |   4.1  39.4  260  16  8   7.0   3.8
 12000   5.0  41.0  255  17  9   7.1   3.9 |   5.1  41.2  255  15  8   7.2   4.0
 11500   6.0  42.8  255  17  9   7.0   3.9 |   6.2  43.2  255  15  8   7.1   3.9
 11000   7.0  44.6  250  17  9   6.9   3.8 |   7.1  44.8  255  14  7   6.8   3.7
 10500   8.0  46.4  250  16  8   6.4   3.5 |   8.1  46.6  250  14  7   6.3   3.4
 10250   8.4  47.1  245  16  8   5.5   3.0 |   8.5  47.3  250  14  7   5.9   3.2
 10000   8.8  47.8  245  16  8   6.1   3.3 |   9.0  48.2  250  14  7   7.0   3.8
  9750   9.2  48.6  245  16  8   6.6   3.6 |   9.5  49.1  250  14  7   7.7   4.2
  9500   9.7  49.5  245  15  8   6.1   3.3 |  10.0  50.0  250  14  7   6.7   3.7
  9250  10.1  50.2  245  15  7   5.1   2.8 |  10.4  50.7  245  14  7   5.3   2.9
  9000  10.5  50.9  240  14  7   5.9   3.2 |  10.8  51.4  245  13  7   6.4   3.5
  8750  11.0  51.8  240  12  6   7.2   3.9 |  11.3  52.3  245  12  6   7.7   4.2
  8500  11.5  52.7  235  10  5   6.2   3.4 |  11.8  53.2  240  11  5   6.1   3.3
  8250  11.9  53.4  225   9  5   5.2   2.9 |  12.2  54.0  235   9  5   4.6   2.5
  8000  12.3  54.1  220   8  4   5.6   3.1 |  12.6  54.7  230   8  4   5.6   3.0
  7750  12.7  54.9  205   8  4   5.6   3.1 |  13.0  55.4  220   7  3   6.4   3.5
  7500  13.1  55.6  195   8  4   3.7   2.0 |  13.5  56.3  205   6  3   5.4   3.0
  7250  13.3  55.9  190   9  5   2.4   1.3 |  13.8  56.8  200   6  3   4.8   2.6
  7000  13.5  56.3  180  11  5   3.1   1.7 |  14.2  57.6  195   6  3   4.2   2.3
  6750  13.6  56.5  175  12  6   1.1   0.6 |  14.5  58.1  185   6  3   6.2   3.4
  6500  13.6  56.5  170  11  6  -1.8  -1.0 |  15.1  59.2  185   6  3   9.1   5.0
  6250  13.5  56.3  160  10  5   0.2   0.1 |  15.7  60.3  185   5  3   9.1   5.0
  6000  13.4  56.1  150   9  5  -6.8  -3.7 |  16.4  61.5  185   5  2   8.9   4.9
  5750  12.3  54.1  150   9  5 -19.8 -10.8 |  17.2  63.0  185   5  2  13.8   7.6
  5500  10.7  51.3  130   6  3 -20.3 -11.1 |  18.5  65.3  190   4  2  22.7  12.4
  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

           10/24/2014 at 1500 MDT          |       10/24/2014 at 1800 MDT
                                           |
K index... -5.3  LI... +6.2                | K index... -2.2  LI... +5.7
CAPE... 0.0  CIN... -0.9                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -70.2 -94.4  280  35 18   2.7   1.5 | -70.6 -95.1  265  36 18   3.6   2.0
 45000 -64.8 -84.6  270  36 19   6.0   3.3 | -64.6 -84.3  265  40 21   5.3   2.9
 40000 -55.7 -68.3  260  41 21   7.0   3.9 | -56.4 -69.5  270  44 23   7.5   4.1
 38000 -51.5 -60.7  270  40 21   7.0   3.8 | -51.9 -61.4  265  42 22   7.5   4.1
 36000 -46.8 -52.2  275  40 21   7.0   3.9 | -46.9 -52.4  265  40 20   7.5   4.1
 34000 -41.9 -43.4  280  39 20   8.3   4.5 | -41.9 -43.4  265  37 19   8.5   4.7
 32000 -36.9 -34.4  280  38 20   8.2   4.5 | -36.8 -34.2  265  34 17   8.5   4.6
 30000 -31.7 -25.1  280  36 19   8.7   4.8 | -31.8 -25.2  270  31 16   8.3   4.6
 29000 -29.1 -20.4  280  35 18   8.7   4.8 | -29.3 -20.7  270  29 15   8.3   4.6
 28000 -26.5 -15.7  280  34 18   8.5   4.7 | -26.8 -16.2  275  28 14   8.5   4.7
 27000 -24.0 -11.2  275  34 17   8.4   4.6 | -24.2 -11.6  270  29 15   8.6   4.7
 26000 -21.5  -6.7  275  34 17   8.4   4.6 | -21.6  -6.9  265  29 15   8.6   4.7
 25000 -19.0  -2.2  270  33 17   8.4   4.6 | -19.0  -2.2  265  30 16   8.6   4.7
 24000 -16.8   1.8  270  33 17   6.9   3.8 | -16.6   2.1  265  31 16   7.7   4.2
 23000 -14.7   5.5  265  33 17   6.9   3.8 | -14.3   6.3  270  32 17   7.7   4.2
 22000 -12.6   9.3  260  33 17   6.9   3.8 | -12.0  10.4  270  34 17   7.6   4.2
 21000 -10.1  13.8  255  33 17   6.8   3.7 | -10.0  14.0  270  34 17   6.5   3.6
 20000  -8.0  17.6  250  32 17   6.8   3.7 |  -7.5  18.5  260  34 17   6.5   3.6
 19500  -7.0  19.4  245  32 17   6.5   3.6 |  -6.5  20.3  260  34 17   6.1   3.4
 19000  -6.2  20.8  245  32 17   5.2   2.8 |  -5.8  21.6  260  33 17   4.5   2.5
 18500  -5.4  22.3  245  32 17   5.3   2.9 |  -5.1  22.8  260  32 17   4.6   2.5
 18000  -4.6  23.7  245  32 17   4.7   2.6 |  -4.4  24.1  260  32 16   4.4   2.4
 17500  -3.9  25.0  245  31 16   4.5   2.5 |  -3.8  25.2  260  30 16   4.4   2.4
 17000  -3.3  26.1  245  30 15   4.4   2.4 |  -3.1  26.4  260  29 15   4.3   2.3
 16500  -2.7  27.1  250  28 15   3.8   2.1 |  -2.5  27.5  260  28 14   3.9   2.1
 16000  -2.1  28.2  250  26 13   3.6   2.0 |  -2.0  28.4  260  26 13   3.8   2.1
 15500  -1.4  29.5  250  24 12   5.5   3.0 |  -1.3  29.7  260  24 13   5.5   3.0
 15000  -0.6  30.9  255  22 12   5.5   3.0 |  -0.5  31.1  260  23 12   5.5   3.0
 14500   0.2  32.4  255  21 11   6.2   3.4 |   0.3  32.5  265  21 11   6.5   3.6
 14000   1.1  34.0  255  20 10   6.5   3.6 |   1.4  34.5  260  20 10   6.9   3.8
 13500   2.1  35.8  255  18  9   7.0   3.8 |   2.4  36.3  260  18  9   7.3   4.0
 13000   3.2  37.8  255  18  9   7.5   4.1 |   3.5  38.3  255  18  9   7.8   4.3
 12500   4.3  39.7  255  17  9   7.7   4.2 |   4.5  40.1  250  17  9   8.2   4.5
 12000   5.4  41.7  250  16  8   8.0   4.4 |   5.7  42.3  245  16  8   8.8   4.8
 11500   6.6  43.9  250  16  8   8.1   4.5 |   6.9  44.4  240  15  8   8.8   4.9
 11000   7.7  45.9  245  15  8   8.3   4.6 |   8.2  46.8  235  13  7   8.4   4.6
 10500   8.9  48.0  245  14  7   7.4   4.1 |   9.4  48.9  230  12  6   5.5   3.0
 10250   9.3  48.7  245  14  7   6.5   3.5 |   9.7  49.5  230  11  6   4.4   2.4
 10000   9.8  49.6  240  14  7   7.8   4.3 |  10.2  50.4  230  11  5   9.4   5.2
  9750  10.4  50.7  240  13  7   8.4   4.6 |  11.0  51.8  225  10  5  10.8   5.9
  9500  11.0  51.8  240  12  6   7.6   4.2 |  11.7  53.1  220   9  5   8.5   4.7
  9250  11.5  52.7  240  12  6   6.7   3.6 |  12.2  54.0  220   9  4   5.0   2.7
  9000  12.0  53.6  235  11  6   6.6   3.6 |  12.6  54.7  215   8  4   6.6   3.6
  8750  12.4  54.3  235  10  5   6.9   3.8 |  13.2  55.8  210   7  4   8.8   4.8
  8500  12.9  55.2  230   8  4   5.8   3.2 |  13.8  56.8  205   7  4   7.1   3.9
  8250  13.3  55.9  230   7  4   4.6   2.5 |  14.2  57.6  200   6  3   5.9   3.2
  8000  13.7  56.7  230   6  3   5.1   2.8 |  14.7  58.5  195   6  3   6.0   3.3
  7750  14.0  57.2  225   4  2   5.9   3.2 |  15.1  59.2  185   5  3   5.7   3.1
  7500  14.5  58.1  225   3  1   7.6   4.2 |  15.5  59.9  180   5  2   5.3   2.9
  7250  15.1  59.2  230   3  1   8.4   4.6 |  15.9  60.6  170   4  2   5.2   2.9
  7000  15.7  60.3  240   2  1   8.4   4.6 |  16.3  61.3  160   3  2   4.8   2.6
  6750  16.4  61.5  245   2  1   9.8   5.4 |  16.6  61.9  140   2  1   5.6   3.1
  6500  17.2  63.0  245   2  1  10.6   5.8 |  17.1  62.8  125   2  1   7.9   4.3
  6250  18.0  64.4  250   2  1  10.4   5.7 |  17.7  63.9  115   1  1   8.4   4.6
  6000  18.7  65.7  255   2  1  10.2   5.6 |  18.4  65.1  000   0  0   8.8   4.8
  5750  19.6  67.3  255   2  1  14.2   7.8 |  19.0  66.2  000   0  0   7.7   4.2
  5500  20.9  69.6  260   3  1  21.7  11.9 |  19.4  66.9  355   1  0   4.1   2.3
  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
________________________________________________________________________________

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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