Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 231245
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0645 MDT Monday, October 23, 2017

This forecast is for Monday, October 23, 2017:

If the trigger temperature of 67.7 F/19.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 151 ft/min (0.8 m/s)
   Maximum height of thermals.................. 8628 ft MSL (3789 ft AGL)

Forecast maximum temperature................... 67.0 F/19.9 C
Time of trigger temperature.................... 1500 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6868 ft MSL (2029 ft AGL)
Thermal soaring outlook for Tuesday 10/24...... Poor

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

Remarks...

Sunrise/Sunset.................... 07:32:27 / 18:25:18 MDT
Total possible sunshine........... 10 hr 52 min 51 sec (652 min 51 sec)
Altitude of sun at 12:58:29 MDT... 39.24 degrees

Upper air data from rawinsonde observation taken on 10/23/2017 at 0600 MDT

Freezing level.................. 11644 ft MSL (6805 ft AGL)
Convective condensation level... 22485 ft MSL (17646 ft AGL)
Lifted condensation level....... 15727 ft MSL (10888 ft AGL)
Lifted index.................... +12.1
K index......................... +7.1

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  -64.1 -83.4   290   72   37   3.0   1.6   91.2 196.1    41.2      M    M
 45000  -65.3 -85.5   295   71   37   2.9   1.6   64.6 148.2    27.8      M    M
 40000  -60.8 -77.4   330   69   35   5.9   3.3   48.4 119.2    19.1      M    M
 38000  -56.1 -69.0   330   65   34   8.8   4.9   46.5 115.7    18.4      M    M
 36000  -50.8 -59.4   330   62   32   8.8   4.9   45.9 114.6    18.4      M    M
 34000  -44.9 -48.8   320   65   34   9.3   5.1   44.9 112.9    18.3      M    M
 32000  -39.3 -38.7   315   68   35   9.4   5.1   44.6 112.4    18.5      M    M
 30000  -33.6 -28.5   315   70   36   9.6   5.3   44.6 112.3    18.9      M    M
 29000  -30.7 -23.3   310   67   35   7.1   3.9   44.5 112.1    19.1      M    M
 28000  -29.2 -20.6   305   65   33   6.1   3.3   42.6 108.6    17.8      M    M
 27000  -26.6 -15.9   305   65   33   9.3   5.1   42.1 107.8    17.7      M    M
 26000  -23.8 -10.8   305   64   33   9.3   5.1   41.9 107.5    17.8      M    M
 25000  -21.3  -6.3   305   64   33   4.9   2.7   41.5 106.7    17.6      M    M
 24000  -19.4  -2.9   305   64   33   6.9   3.8   40.3 104.5    16.8      M    M
 23000  -17.3   0.9   310   65   33   7.0   3.8   39.3 102.8    16.2      M    M
 22000  -15.3   4.5   310   62   32   7.0   3.8   38.3 100.9    15.5      M    M
 21000  -13.2   8.2   310   59   31   7.0   3.8   37.2  99.0    14.7      M    M
 20000  -11.1  12.0   310   56   29   5.7   3.1   36.3  97.3    14.1      M    M
 19500  -10.9  12.4   310   55   28   3.6   2.0   34.9  94.8    12.9      M    M
 19000   -9.7  14.5   310   54   28   7.9   4.3   34.7  94.4    12.8      M    M
 18500   -8.1  17.4   310   52   27   6.9   3.8   33.9  93.0    12.2      M    M
 18000   -7.1  19.2   315   52   27   6.9   3.8   33.4  92.1    11.8      M    M
 17500   -6.1  21.0   315   51   26   4.8   2.6   32.9  91.3    11.5      M    M
 17000   -5.7  21.7   315   48   25   3.1   1.7   31.8  89.2    10.5      M    M
 16500   -5.2  22.6   315   40   21   3.0   1.6   30.6  87.1     9.5      M    M
 16000   -4.8  23.4   315   32   17   4.6   2.5   29.5  85.2     8.6      M    M
 15500   -4.0  24.8   320   27   14   5.1   2.8   28.8  83.8     7.9      M    M
 15000   -3.2  26.2   330   23   12   5.1   2.8   28.0  82.4     7.2      M    M
 14500   -2.5  27.5   325   20   10   5.0   2.8   27.2  81.0     6.6      M    M
 14000   -1.7  28.9   320   18    9   4.3   2.4   26.4  79.6     5.9      M    M
 13500   -1.1  30.0   310   21   11  -9.8  -5.4   25.6  78.0     5.1      M    M
 13000   -2.7  27.1   305   24   12   4.8   2.6   22.3  72.1     2.0      M    M
 12500   -1.9  28.6   305   27   14   6.5   3.6   21.6  70.9     1.4      M    M
 12000   -1.0  30.2   300   30   15   7.7   4.2   21.1  69.9     0.9      M    M
 11500    0.5  32.9   300   28   14   9.7   5.3   21.0  69.8     0.8      M    M
 11000    2.0  35.6   295   26   13   9.7   5.3   21.0  69.8     0.9      M    M
 10500    3.4  38.1   295   24   12   9.2   5.1   21.0  69.8     0.9      M    M
 10250    4.1  39.4   295   24   12   8.7   4.8   20.9  69.6     0.8      M    M
 10000    4.8  40.6   295   24   12   8.8   4.9   20.8  69.5     0.8      M    M
  9750    5.5  41.9   295   24   12   8.9   4.9   20.8  69.4     0.7      M    M
  9500    6.1  43.0   295   23   12   8.7   4.8   20.7  69.2     0.7      M    M
  9250    6.8  44.2   295   23   12   9.4   5.2   20.6  69.1     0.6      M    M
  9000    7.5  45.5   295   23   12   6.8   3.7   20.6  69.0     0.6      M    M
  8750    7.9  46.2   295   18    9   5.3   2.9   20.2  68.4     0.3      M    M
  8500    8.2  46.8   290   12    6  -2.0  -1.1   19.7  67.5    -0.2    245  1.2
  8250    7.8  46.0   285    7    4  -3.7  -2.0   18.5  65.3    -1.3    250  1.3
  8000    7.9  46.2   240    2    1   5.8   3.2   17.9  64.3    -1.9    237  1.2
  7750    8.4  47.1   210    2    1   7.0   3.8   17.7  63.8    -2.1    215  1.1
  7500    8.9  48.0   190    2    1   6.7   3.7   17.5  63.4    -2.4    192  1.0
  7250    9.4  48.9   175    2    1   6.8   3.7   17.2  63.0    -2.6    170  0.9
  7000    9.9  49.8   160    2    1   6.8   3.8   17.0  62.6    -2.8    148  0.7
  6750   10.4  50.7   160    4    2   6.5   3.6   16.8  62.2    -3.1    125  0.6
  6500   10.9  51.6   165    5    3   7.8   4.3   16.6  61.8    -3.3    103  0.5
  6250   11.4  52.5   165    7    4   2.9   1.6   16.3  61.4    -3.5     80  0.4
  6000   11.3  52.3   165    9    5  -5.4  -3.0   15.4  59.8    -4.4     78  0.4
  5750   10.8  51.4   160   10    5  -7.4  -4.1   14.2  57.5    -5.7     85  0.4
  5500   10.3  50.5   145   10    5  -4.5  -2.5   12.9  55.3    -6.9     93  0.5
  5250    9.6  49.3   140   11    6 -19.8 -10.9   11.6  52.8    -8.3    105  0.5
  5000    7.2  45.0   135    8    4 -38.4 -21.0    8.4  47.2   -11.5    169  0.9

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

           10/23/2017 at 0900 MDT          |       10/23/2017 at 1200 MDT
                                           |
K index... +7.4  LI... +7.4                | K index... +1.2  LI... +7.9
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -65.8 -86.4  315  48 25  -0.1  -0.1 | -66.5 -87.7  320  50 26  -0.1  -0.1
 45000 -65.2 -85.4  320  60 31   2.3   1.3 | -65.8 -86.4  330  62 32   2.8   1.5
 40000 -61.4 -78.5  330  67 35   7.9   4.3 | -61.3 -78.3  335  65 34   9.5   5.2
 38000 -56.2 -69.2  330  66 34   8.7   4.8 | -55.8 -68.4  330  65 34   9.1   5.0
 36000 -51.0 -59.8  325  64 33   8.7   4.8 | -50.4 -58.7  325  66 34   9.1   5.0
 34000 -44.8 -48.6  325  65 33   9.4   5.2 | -44.0 -47.2  320  67 35   9.4   5.2
 32000 -39.1 -38.4  325  66 34   9.4   5.1 | -38.4 -37.1  325  68 35   9.4   5.2
 30000 -33.6 -28.5  325  65 33   9.2   5.1 | -32.9 -27.2  325  67 35   9.0   4.9
 29000 -30.8 -23.4  325  64 33   9.2   5.1 | -30.2 -22.4  325  67 34   9.0   4.9
 28000 -28.0 -18.4  325  63 32   8.4   4.6 | -27.6 -17.7  325  66 34   8.2   4.5
 27000 -25.9 -14.6  325  62 32   7.1   3.9 | -25.3 -13.5  325  64 33   7.5   4.1
 26000 -23.8 -10.8  325  60 31   7.2   3.9 | -23.1  -9.6  330  63 32   7.5   4.1
 25000 -21.6  -6.9  325  59 31   7.2   3.9 | -20.8  -5.4  330  61 31   7.7   4.2
 24000 -19.6  -3.3  325  57 30   7.0   3.8 | -19.0  -2.2  330  59 30   5.8   3.2
 23000 -17.5   0.5  325  55 28   7.0   3.8 | -17.2   1.0  330  56 29   5.8   3.2
 22000 -15.4   4.3  325  53 27   7.0   3.8 | -15.5   4.1  330  53 27   5.9   3.3
 21000 -13.5   7.7  325  51 26   6.6   3.6 | -13.4   7.9  330  51 26   7.2   4.0
 20000 -11.5  11.3  325  49 25   6.6   3.6 | -11.3  11.7  325  49 25   7.2   4.0
 19500 -10.1  13.8  325  47 24   6.5   3.6 | -10.2  13.6  325  48 25   7.3   4.0
 19000  -9.2  15.4  325  46 23   5.8   3.2 |  -8.7  16.3  325  47 24   6.1   3.3
 18500  -8.3  17.1  325  44 23   5.9   3.2 |  -7.8  18.0  325  46 23   6.1   3.3
 18000  -7.4  18.7  325  43 22   5.7   3.1 |  -6.9  19.6  325  44 23   6.1   3.3
 17500  -6.6  20.1  325  41 21   5.7   3.1 |  -6.0  21.2  325  43 22   6.1   3.3
 17000  -5.8  21.6  325  40 20   5.7   3.1 |  -5.1  22.8  330  42 22   5.8   3.2
 16500  -4.9  23.2  325  38 20   5.9   3.3 |  -4.4  24.1  330  40 21   4.9   2.7
 16000  -4.0  24.8  320  37 19   6.1   3.3 |  -3.7  25.3  330  39 20   4.9   2.7
 15500  -3.2  26.2  320  35 18   4.4   2.4 |  -2.9  26.8  330  37 19   5.3   2.9
 15000  -2.6  27.3  320  33 17   4.5   2.5 |  -2.1  28.2  335  35 18   5.3   2.9
 14500  -2.0  28.4  320  31 16   2.8   1.6 |  -1.3  29.7  335  34 17   5.2   2.9
 14000  -1.7  28.9  320  28 14   2.3   1.2 |  -0.5  31.1  335  32 16   5.2   2.9
 13500  -1.4  29.5  320  25 13   1.7   0.9 |   0.2  32.4  335  30 15   4.3   2.3
 13000  -1.3  29.7  320  21 11   1.2   0.7 |   0.8  33.4  335  28 14   3.6   2.0
 12500  -1.2  29.8  320  17  9   1.8   1.0 |   1.3  34.3  335  25 13   2.4   1.3
 12000  -0.8  30.6  325  14  7   2.8   1.5 |   1.3  34.3  335  21 11   1.0   0.6
 11500  -0.5  31.1  325  11  6   4.1   2.2 |   1.4  34.5  330  17  9   1.2   0.6
 11000   0.4  32.7  330  10  5   6.0   3.3 |   1.5  34.7  335  13  6   1.5   0.8
 10500   1.2  34.2  340  10  5   7.0   3.8 |   1.6  34.9  340   9  4   3.1   1.7
 10250   1.8  35.2  340  10  5   8.6   4.7 |   1.9  35.4  345   8  4   5.3   2.9
 10000   2.4  36.3  340  10  5   7.6   4.2 |   2.3  36.1  350   7  3   4.6   2.5
  9750   3.0  37.4  340  10  5   7.0   3.9 |   2.6  36.7  360   6  3   4.6   2.5
  9500   3.5  38.3  340  11  6   6.9   3.8 |   3.0  37.4  010   6  3   5.8   3.2
  9250   4.0  39.2  340  11  6   6.6   3.6 |   3.5  38.3  020   6  3   6.7   3.7
  9000   4.5  40.1  340  12  6   6.9   3.8 |   4.0  39.2  025   6  3   6.5   3.5
  8750   5.0  41.0  340  12  6   6.8   3.7 |   4.5  40.1  035   6  3   6.2   3.4
  8500   5.5  41.9  340  12  6   5.4   3.0 |   4.9  40.8  040   6  3   5.7   3.1
  8250   5.9  42.6  340  11  6   4.7   2.6 |   5.3  41.5  045   6  3   5.2   2.8
  8000   6.3  43.3  340  10  5   5.3   2.9 |   5.8  42.4  050   6  3   6.4   3.5
  7750   6.7  44.1  340   9  5   3.3   1.8 |   6.3  43.3  055   5  3   6.9   3.8
  7500   6.9  44.4  340   7  4   1.5   0.8 |   6.8  44.2  055   5  2   5.8   3.2
  7250   7.0  44.6  340   5  3   1.6   0.9 |   7.2  45.0  055   4  2   5.7   3.1
  7000   7.2  45.0  340   4  2   2.4   1.3 |   7.7  45.9  055   4  2   6.5   3.6
  6750   7.5  45.5  340   2  1   3.9   2.1 |   8.3  46.9  050   3  2   9.0   4.9
  6500   7.8  46.0  340   1  1   3.6   2.0 |   9.0  48.2  050   3  1  10.0   5.5
  6250   8.1  46.6  000   0  0   4.7   2.6 |   9.8  49.6  050   3  1   9.7   5.3
  6000   8.4  47.1  170   1  0  -0.5  -0.3 |  10.5  50.9  050   2  1  10.8   5.9
  5750   8.0  46.4  125   2  1  -6.3  -3.5 |  11.5  52.7  050   2  1  16.5   9.0
  5500   7.7  45.9  110   2  1  -1.6  -0.9 |  13.0  55.4  040   2  1  23.3  12.8
  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

           10/23/2017 at 1500 MDT          |       10/23/2017 at 1800 MDT
                                           |
K index... +3.3  LI... +7.6                | K index... +1.3  LI... +6.2
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -68.0 -90.4  325  52 27  -1.4  -0.8 | -67.9 -90.2  335  54 28  -1.4  -0.7
 45000 -68.1 -90.6  330  63 33   5.1   2.8 | -68.0 -90.4  335  65 33   5.0   2.8
 40000 -60.2 -76.4  330  65 34   9.4   5.1 | -60.1 -76.2  325  64 33   9.5   5.2
 38000 -54.9 -66.8  325  66 34   8.9   4.9 | -54.7 -66.5  325  65 34   9.0   5.0
 36000 -49.6 -57.3  325  66 34   8.9   4.9 | -49.3 -56.7  330  67 34   9.0   5.0
 34000 -44.2 -47.6  320  66 34   9.0   5.0 | -43.3 -45.9  330  67 35   8.9   4.9
 32000 -38.1 -36.6  320  65 33   9.0   4.9 | -37.9 -36.2  330  67 35   8.9   4.9
 30000 -32.9 -27.2  325  62 32   8.7   4.8 | -32.9 -27.2  330  64 33   8.2   4.5
 29000 -30.3 -22.5  325  61 31   8.7   4.8 | -30.5 -22.9  330  62 32   8.2   4.5
 28000 -27.7 -17.9  325  60 31   8.1   4.4 | -28.0 -18.4  330  60 31   7.9   4.3
 27000 -25.4 -13.7  330  58 30   7.6   4.2 | -25.8 -14.4  330  57 29   7.6   4.2
 26000 -23.1  -9.6  330  56 29   7.7   4.2 | -23.5 -10.3  335  53 27   7.6   4.2
 25000 -20.8  -5.4  330  55 28   7.8   4.3 | -21.2  -6.2  335  49 25   7.8   4.3
 24000 -19.1  -2.4  330  52 27   5.4   2.9 | -19.3  -2.7  335  46 24   6.1   3.3
 23000 -17.5   0.5  335  49 25   5.4   3.0 | -17.5   0.5  340  43 22   6.1   3.4
 22000 -15.9   3.4  335  46 24   5.6   3.0 | -15.7   3.7  340  41 21   6.1   3.3
 21000 -14.0   6.8  335  45 23   6.7   3.7 | -13.9   7.0  345  40 20   5.8   3.2
 20000 -12.0  10.4  335  45 23   6.7   3.7 | -12.2  10.0  345  39 20   5.8   3.2
 19500 -11.0  12.2  335  45 23   6.6   3.6 | -11.3  11.7  350  39 20   5.7   3.1
 19000  -9.4  15.1  335  44 23   7.7   4.2 |  -9.7  14.5  350  39 20   8.3   4.6
 18500  -8.2  17.2  335  44 23   7.7   4.2 |  -8.4  16.9  350  39 20   8.4   4.6
 18000  -7.1  19.2  335  44 23   6.9   3.8 |  -7.2  19.0  350  40 20   7.2   4.0
 17500  -6.1  21.0  335  44 22   6.8   3.7 |  -6.2  20.8  350  40 21   7.1   3.9
 17000  -5.1  22.8  335  43 22   6.3   3.4 |  -5.1  22.8  350  41 21   6.6   3.6
 16500  -4.3  24.3  340  42 22   5.4   3.0 |  -4.2  24.4  350  41 21   5.8   3.2
 16000  -3.5  25.7  340  41 21   5.5   3.0 |  -3.3  26.1  350  41 21   6.0   3.3
 15500  -2.8  27.0  340  40 21   4.8   2.6 |  -2.7  27.1  350  41 21   3.6   2.0
 15000  -2.1  28.2  340  38 20   4.9   2.7 |  -2.2  28.0  350  40 20   4.0   2.2
 14500  -1.4  29.5  340  37 19   4.9   2.7 |  -1.6  29.1  350  39 20   3.6   2.0
 14000  -0.6  30.9  340  36 19   5.0   2.7 |  -1.1  30.0  350  37 19   3.6   2.0
 13500   0.2  32.4  340  35 18   4.4   2.4 |  -0.5  31.1  350  36 18   2.7   1.5
 13000   0.8  33.4  340  34 17   4.1   2.3 |  -0.1  31.8  350  34 17   2.4   1.3
 12500   1.5  34.7  345  32 17   3.5   1.9 |   0.3  32.5  355  31 16   2.6   1.4
 12000   1.9  35.4  345  28 15   2.8   1.5 |   0.7  33.3  355  28 14   2.9   1.6
 11500   2.3  36.1  345  25 13   2.1   1.1 |   1.0  33.8  355  24 12   4.1   2.2
 11000   2.4  36.3  350  19 10   1.8   1.0 |   1.7  35.1  355  19 10   5.5   3.0
 10500   2.5  36.5  360  14  7   3.2   1.8 |   2.4  36.3  355  14  7   7.5   4.1
 10250   2.8  37.0  005  12  6   4.3   2.4 |   3.0  37.4  355  13  6   9.1   5.0
 10000   3.0  37.4  010  10  5   4.9   2.7 |   3.6  38.5  360  11  6   8.0   4.4
  9750   3.4  38.1  015  10  5   5.8   3.2 |   4.1  39.4  360  10  5   7.6   4.2
  9500   3.8  38.8  020   9  5   6.3   3.4 |   4.7  40.5  005   9  5   8.0   4.4
  9250   4.3  39.7  020   8  4   6.5   3.6 |   5.3  41.5  005   9  5   7.8   4.3
  9000   4.8  40.6  020   8  4   7.2   3.9 |   5.9  42.6  010   8  4   8.6   4.7
  8750   5.4  41.7  020   7  4   8.3   4.5 |   6.6  43.9  010   8  4   8.8   4.9
  8500   6.0  42.8  020   6  3   8.2   4.5 |   7.2  45.0  010   7  4   7.6   4.2
  8250   6.6  43.9  020   6  3   7.7   4.2 |   7.7  45.9  010   6  3   6.8   3.7
  8000   7.2  45.0  020   6  3   8.9   4.9 |   8.2  46.8  010   6  3   8.5   4.6
  7750   7.9  46.2  020   5  3  10.1   5.5 |   8.9  48.0  015   5  3   8.9   4.9
  7500   8.7  47.7  020   5  3   9.8   5.4 |   9.5  49.1  010   5  2   7.5   4.1
  7250   9.4  48.9  015   5  3   9.8   5.4 |  10.1  50.2  010   4  2   8.0   4.4
  7000  10.1  50.2  015   5  2  10.1   5.5 |  10.7  51.3  005   3  2   7.3   4.0
  6750  10.9  51.6  015   4  2  10.2   5.6 |  11.2  52.2  360   3  1   8.1   4.4
  6500  11.7  53.1  015   4  2  10.0   5.5 |  11.9  53.4  360   2  1   9.2   5.1
  6250  12.4  54.3  015   4  2  10.1   5.6 |  12.6  54.7  355   1  1   8.8   4.8
  6000  13.2  55.8  015   4  2  10.1   5.6 |  13.3  55.9  345   1  0   9.3   5.1
  5750  14.1  57.4  010   3  2  15.5   8.5 |  13.9  57.0  330   1  0   7.6   4.2
  5500  15.6  60.1  010   4  2  24.4  13.4 |  14.3  57.7  340   1  0   3.5   1.9
  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
________________________________________________________________________________

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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