Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 151248
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0647 MDT Sunday, October 15, 2017

This forecast is for Sunday, October 15, 2017:

If the trigger temperature of 55.4 F/13.0 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 243 ft/min (1.2 m/s)
   Maximum height of thermals.................. 9798 ft MSL (4959 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... 1145 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................. 9316 ft MSL (4476 ft AGL)
Thermal soaring outlook for Monday 10/16....... Excellent

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

Remarks...

Sunrise/Sunset.................... 07:24:10 / 18:36:26 MDT
Total possible sunshine........... 11 hr 12 min 17 sec (672 min 17 sec)
Altitude of sun at 12:59:52 MDT... 42.10 degrees

Upper air data from rawinsonde observation taken on 10/15/2017 at 0600 MDT

Freezing level.................. 13213 ft MSL (8374 ft AGL)
Convective condensation level... 24033 ft MSL (19194 ft AGL)
Lifted condensation level....... 18013 ft MSL (13173 ft AGL)
Lifted index.................... +11.7
K index......................... -26.3

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  -64.5 -84.1   270   54   28   2.4   1.3   92.3 198.1    42.5      M    M
 45000  -59.3 -74.7   280   69   35   0.6   0.3   75.1 167.1    35.2      M    M
 40000  -58.8 -73.8   280   62   32   5.8   3.2   52.9 127.2    23.1      M    M
 38000  -55.2 -67.4   285   54   28   6.1   3.3   49.6 121.2    21.5      M    M
 36000  -52.3 -62.1   290   45   23   4.1   2.2   45.3 113.6    19.1      M    M
 34000  -48.1 -54.6   295   46   24   7.4   4.1   42.8 109.1    17.8      M    M
 32000  -43.9 -47.0   295   45   23   8.0   4.4   40.8 105.4    16.8      M    M
 30000  -38.5 -37.3   300   46   24   7.9   4.4   39.2 102.6    16.1      M    M
 29000  -36.1 -33.0   300   46   23   7.9   4.4   38.4 101.1    15.7      M    M
 28000  -33.8 -28.8   300   45   23   7.0   3.9   37.7  99.8    15.3      M    M
 27000  -31.7 -25.1   300   45   23   7.4   4.0   36.6  97.8    14.6      M    M
 26000  -29.2 -20.6   300   44   23   8.6   4.7   36.0  96.8    14.4      M    M
 25000  -26.6 -15.9   300   44   23   8.6   4.7   35.6  96.2    14.2      M    M
 24000  -24.0 -11.2   305   46   24   8.7   4.8   35.2  95.4    14.1      M    M
 23000  -21.6  -6.9   305   43   22   6.5   3.5   34.6  94.2    13.7      M    M
 22000  -19.7  -3.5   300   40   21   6.5   3.6   33.4  92.2    12.9      M    M
 21000  -17.8  -0.0   300   37   19   6.3   3.5   32.2  89.9    12.0      M    M
 20000  -15.9   3.4   295   34   18   6.4   3.5   31.0  87.9    11.1      M    M
 19500  -15.0   5.0   295   33   17   7.0   3.8   30.5  86.8    10.6      M    M
 19000  -13.8   7.2   295   32   16   8.2   4.5   30.1  86.1    10.4      M    M
 18500  -12.6   9.3   295   31   16   8.5   4.7   29.8  85.7    10.2      M    M
 18000  -11.3  11.7   300   30   15   8.5   4.7   29.6  85.3    10.1      M    M
 17500  -10.0  14.0   300   29   15   8.2   4.5   29.4  85.0    10.0      M    M
 17000   -8.9  16.0   305   28   15   7.1   3.9   29.1  84.3     9.7      M    M
 16500   -7.2  19.0   300   29   15   7.1   3.9   28.4  83.1     9.3      M    M
 16000   -6.2  20.8   300   29   15   7.1   3.9   28.0  82.3     8.9      M    M
 15500   -5.1  22.8   295   28   15   7.3   4.0   27.5  81.5     8.5      M    M
 15000   -4.0  24.8   290   28   14   7.6   4.1   27.2  80.9     8.3      M    M
 14500   -2.8  27.0   295   26   14   7.6   4.2   26.8  80.2     8.0      M    M
 14000   -1.7  28.9   295   25   13   7.6   4.2   26.5  79.6     7.8      M    M
 13500   -0.5  31.1   285   22   11   7.7   4.2   26.1  79.0     7.5      M    M
 13000    0.6  33.1   280   20   10   8.6   4.7   25.7  78.3     7.2      M    M
 12500    1.2  34.2   290   15    8  -0.7  -0.4   24.8  76.6     6.4      M    M
 12000    1.2  34.2   305   12    6   0.4   0.2   23.3  73.9     4.9      M    M
 11500    1.6  34.9   305   11    5   5.2   2.8   22.2  71.9     3.9      M    M
 11000    2.4  36.3   300    9    5   4.8   2.7   21.4  70.5     3.2      M    M
 10500    3.0  37.4   300    8    4   2.3   1.3   20.5  68.9     2.4      M    M
 10250    3.3  37.9   300    4    2   4.8   2.6   19.9  67.9     2.0      M    M
 10000    3.5  38.3   000    0    0  -5.1  -2.8   19.4  66.9     1.5      M    M
  9750    2.4  36.3   120    1    1 -19.6 -10.8   17.5  63.4    -0.3    248  1.3
  9500    1.2  34.2   120    2    1  -8.0  -4.4   15.4  59.8    -2.3    278  1.4
  9250    1.0  33.8   120    4    2   0.3   0.1   14.6  58.2    -3.2    275  1.4
  9000    0.9  33.6   120    5    3  -1.2  -0.7   13.7  56.7    -4.1    272  1.4
  8750    0.9  33.6   120    5    3   3.9   2.2   13.0  55.4    -4.8    263  1.3
  8500    1.4  34.5   120    5    3   6.4   3.5   12.7  54.9    -5.1    242  1.2
  8250    1.8  35.2   115    5    3   5.8   3.2   12.4  54.4    -5.4    222  1.1
  8000    2.3  36.1   115    5    3   5.6   3.1   12.1  53.8    -5.7    201  1.0
  7750    2.7  36.9   115    6    3   6.9   3.8   11.8  53.3    -6.0    181  0.9
  7500    3.1  37.6   115    8    4   2.0   1.1   11.5  52.7    -6.3    160  0.8
  7250    2.9  37.2   115    9    5  -4.8  -2.6   10.6  51.0    -7.2    159  0.8
  7000    2.6  36.7   115   11    6  -3.2  -1.8    9.5  49.1    -8.3    161  0.8
  6750    2.6  36.7   115   11    6   6.1   3.4    8.8  47.8    -9.0    153  0.8
  6500    3.2  37.8   115   11    5   3.1   1.7    8.6  47.5    -9.2    129  0.7
  6250    3.1  37.6   110   10    5  -1.1  -0.6    7.7  45.9   -10.1    126  0.6
  6000    3.3  37.9   110   10    5   7.3   4.0    7.3  45.1   -10.6    109  0.6
  5750    3.9  39.0   110   10    5   7.6   4.1    7.2  44.9   -10.8     84  0.4
  5500    4.5  40.1   105    9    5  10.4   5.7    7.0  44.7   -10.9     59  0.3
  5250    5.0  41.0   105    9    5  -7.4  -4.1    6.7  44.1   -11.2     39  0.2
  5000    2.9  37.2   105    7    4 -44.7 -24.6    3.9  39.1   -14.1     94  0.5

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

           10/15/2017 at 0900 MDT          |       10/15/2017 at 1200 MDT
                                           |
K index... -9.8  LI... +7.2                | K index... -12.6  LI... +6.4
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 -63.3 -81.9  285  54 28   2.1   1.1 | -63.8 -82.8  290  53 27   1.8   1.0
 45000 -60.3 -76.5  290  59 31   1.2   0.7 | -61.2 -78.2  295  56 29   1.1   0.6
 40000 -58.5 -73.3  300  55 28   3.1   1.7 | -59.6 -75.3  300  50 26   3.8   2.1
 38000 -54.9 -66.8  305  53 28   6.1   3.4 | -55.6 -68.1  300  49 25   6.7   3.7
 36000 -51.3 -60.3  310  52 27   6.1   3.3 | -51.5 -60.7  305  47 24   6.7   3.7
 34000 -47.2 -53.0  310  51 26   7.3   4.0 | -47.1 -52.8  305  45 23   7.8   4.3
 32000 -42.3 -44.1  310  48 25   7.3   4.0 | -41.8 -43.2  305  44 23   7.8   4.3
 30000 -37.9 -36.2  305  46 24   7.4   4.0 | -37.4 -35.3  305  42 22   7.3   4.0
 29000 -35.7 -32.3  305  45 23   7.4   4.0 | -35.2 -31.4  305  41 21   7.3   4.0
 28000 -33.5 -28.3  305  44 23   7.4   4.1 | -33.0 -27.4  305  40 20   7.5   4.1
 27000 -31.1 -24.0  305  43 22   8.1   4.4 | -30.6 -23.1  305  40 21   8.2   4.5
 26000 -28.7 -19.7  305  43 22   8.1   4.4 | -28.1 -18.6  305  40 21   8.2   4.5
 25000 -26.2 -15.2  305  42 22   8.1   4.5 | -25.7 -14.3  305  41 21   8.2   4.5
 24000 -24.0 -11.2  305  42 21   7.3   4.0 | -23.4 -10.1  305  41 21   7.3   4.0
 23000 -21.8  -7.2  305  41 21   7.3   4.0 | -21.2  -6.2  305  41 21   7.3   4.0
 22000 -19.6  -3.3  305  41 21   7.3   4.0 | -19.0  -2.2  305  41 21   7.3   4.0
 21000 -17.5   0.5  305  39 20   7.4   4.0 | -17.0   1.4  305  39 20   6.9   3.8
 20000 -15.3   4.5  305  38 19   7.4   4.1 | -14.9   5.2  305  36 19   6.9   3.8
 19500 -14.2   6.4  305  37 19   7.4   4.1 | -13.9   7.0  300  35 18   6.9   3.8
 19000 -13.1   8.4  305  36 18   7.5   4.1 | -12.9   8.8  300  34 17   7.6   4.2
 18500 -11.9  10.6  305  34 17   7.5   4.1 | -11.1  12.0  300  32 16   7.7   4.2
 18000 -10.3  13.5  300  31 16   7.4   4.0 | -10.0  14.0  300  30 16   7.3   4.0
 17500  -9.2  15.4  300  30 15   7.3   4.0 |  -8.9  16.0  295  29 15   7.2   4.0
 17000  -8.1  17.4  300  28 14   7.3   4.0 |  -7.8  18.0  295  28 14   7.2   4.0
 16500  -7.0  19.4  300  27 14   7.4   4.0 |  -6.8  19.8  295  26 14   7.2   4.0
 16000  -5.9  21.4  300  25 13   7.4   4.0 |  -5.7  21.7  295  25 13   7.3   4.0
 15500  -4.8  23.4  300  24 12   7.4   4.1 |  -4.6  23.7  295  23 12   6.9   3.8
 15000  -3.7  25.3  300  22 12   7.4   4.1 |  -3.6  25.5  295  22 11   6.9   3.8
 14500  -2.6  27.3  300  21 11   7.1   3.9 |  -2.5  27.5  295  20 10   7.7   4.2
 14000  -1.6  29.1  305  20 10   7.1   3.9 |  -1.4  29.5  295  18  9   7.8   4.3
 13500  -0.5  31.1  305  19 10   6.8   3.8 |  -0.3  31.5  295  17  9   7.0   3.9
 13000   0.5  32.9  305  17  9   6.6   3.6 |   0.7  33.3  295  15  8   6.7   3.7
 12500   1.5  34.7  305  16  8   5.7   3.1 |   1.7  35.1  295  13  7   6.1   3.3
 12000   2.2  36.0  310  14  7   4.5   2.5 |   2.6  36.7  295  12  6   5.6   3.1
 11500   2.8  37.0  310  12  6   3.2   1.7 |   3.4  38.1  295  10  5   4.7   2.6
 11000   3.0  37.4  310   9  5   1.3   0.7 |   4.0  39.2  295   8  4   3.9   2.1
 10500   3.2  37.8  315   7  3   0.6   0.3 |   4.5  40.1  290   6  3   3.1   1.7
 10250   3.2  37.8  315   5  3  -0.6  -0.3 |   4.7  40.5  285   5  2   2.3   1.3
 10000   3.2  37.8  320   4  2   0.0   0.0 |   4.9  40.8  280   4  2   2.2   1.2
  9750   3.2  37.8  325   3  1   0.6   0.3 |   5.0  41.0  270   3  1   1.8   1.0
  9500   3.2  37.8  345   2  1   0.5   0.3 |   5.1  41.2  255   2  1   1.4   0.8
  9250   3.2  37.8  025   1  1   0.2   0.1 |   5.2  41.4  230   1  1   1.1   0.6
  9000   3.2  37.8  065   1  1   0.5   0.3 |   5.3  41.5  180   1  1   1.2   0.7
  8750   3.3  37.9  085   2  1   2.0   1.1 |   5.4  41.7  155   1  1   1.5   0.8
  8500   3.5  38.3  090   2  1   2.2   1.2 |   5.5  41.9  145   2  1   1.8   1.0
  8250   3.6  38.5  090   3  1   1.5   0.8 |   5.6  42.1  135   2  1   1.7   0.9
  8000   3.7  38.7  095   3  2   1.9   1.0 |   5.8  42.4  130   2  1   2.3   1.3
  7750   3.9  39.0  095   3  2   2.1   1.2 |   6.0  42.8  125   3  1   2.5   1.4
  7500   4.0  39.2  100   3  2   1.3   0.7 |   6.1  43.0  125   3  1   2.0   1.1
  7250   4.1  39.4  105   4  2   0.8   0.5 |   6.3  43.3  120   2  1   1.8   1.0
  7000   4.2  39.6  110   4  2   0.5   0.3 |   6.4  43.5  115   2  1   2.6   1.4
  6750   4.2  39.6  115   4  2  -1.0  -0.6 |   6.7  44.1  110   2  1   6.7   3.7
  6500   4.0  39.2  115   5  2  -1.7  -0.9 |   7.3  45.1  110   1  1   8.9   4.9
  6250   3.9  39.0  115   5  3  -1.0  -0.5 |   8.0  46.4  110   1  1   8.4   4.6
  6000   3.8  38.8  115   5  3  -5.9  -3.2 |   8.6  47.5  105   1  0   8.8   4.8
  5750   3.2  37.8  105   5  3  -5.4  -2.9 |   9.4  48.9  110   1  0  15.2   8.3
  5500   3.3  37.9  100   5  2   7.9   4.3 |  11.0  51.8  110   1  0  25.8  14.1
  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

           10/15/2017 at 1500 MDT          |       10/15/2017 at 1800 MDT
                                           |
K index... -17.7  LI... +5.9               | K index... -17.5  LI... +6.1
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 -63.9 -83.0  295  54 28   1.2   0.6 | -64.1 -83.4  295  53 27   1.7   0.9
 45000 -62.2 -80.0  295  54 28   1.0   0.6 | -61.4 -78.5  300  53 27   1.7   0.9
 40000 -60.6 -77.1  290  46 24   4.4   2.4 | -58.9 -74.0  300  48 25   3.7   2.0
 38000 -56.2 -69.2  295  44 23   7.3   4.0 | -55.4 -67.7  300  46 24   5.8   3.2
 36000 -51.9 -61.4  295  42 22   7.3   4.0 | -51.9 -61.4  295  44 23   5.8   3.2
 34000 -47.1 -52.8  300  42 21   8.3   4.6 | -47.5 -53.5  295  42 22   8.3   4.5
 32000 -41.5 -42.7  300  41 21   8.3   4.6 | -41.9 -43.4  300  40 21   8.3   4.5
 30000 -36.8 -34.2  305  40 21   7.6   4.2 | -37.1 -34.8  305  38 20   8.0   4.4
 29000 -34.6 -30.3  305  39 20   7.6   4.2 | -34.7 -30.5  305  38 19   8.0   4.4
 28000 -32.3 -26.1  305  38 20   7.5   4.1 | -32.2 -26.0  305  37 19   7.9   4.3
 27000 -30.1 -22.2  305  38 19   7.4   4.1 | -30.0 -22.0  305  37 19   7.4   4.1
 26000 -27.9 -18.2  305  37 19   7.4   4.1 | -27.8 -18.0  305  36 19   7.4   4.1
 25000 -25.6 -14.1  305  37 19   7.4   4.1 | -25.6 -14.1  305  36 19   7.4   4.0
 24000 -23.3  -9.9  305  37 19   7.8   4.3 | -23.3  -9.9  305  36 19   7.8   4.3
 23000 -21.0  -5.8  305  38 20   7.8   4.3 | -21.0  -5.8  305  36 19   7.8   4.3
 22000 -18.7  -1.7  305  39 20   7.8   4.3 | -18.6  -1.5  305  36 19   7.8   4.3
 21000 -16.5   2.3  305  38 19   7.0   3.9 | -16.4   2.5  305  36 18   7.6   4.2
 20000 -14.4   6.1  305  36 18   7.1   3.9 | -14.1   6.6  305  35 18   7.6   4.2
 19500 -13.4   7.9  305  35 18   7.0   3.9 | -13.0   8.6  305  35 18   7.6   4.2
 19000 -12.3   9.9  305  34 18   7.3   4.0 | -11.9  10.6  305  34 18   7.4   4.0
 18500 -10.7  12.7  300  32 16   7.3   4.0 | -10.2  13.6  305  33 17   7.4   4.0
 18000  -9.6  14.7  300  31 16   7.5   4.1 |  -9.1  15.6  305  32 17   7.2   3.9
 17500  -8.5  16.7  295  30 15   7.5   4.1 |  -8.1  17.4  305  31 16   7.2   3.9
 17000  -7.4  18.7  295  29 15   7.6   4.1 |  -7.0  19.4  300  30 15   7.2   4.0
 16500  -6.2  20.8  295  28 14   7.7   4.2 |  -5.9  21.4  300  28 15   7.4   4.1
 16000  -5.1  22.8  295  27 14   7.8   4.3 |  -4.8  23.4  300  27 14   7.4   4.0
 15500  -4.0  24.8  290  26 13   6.7   3.7 |  -3.7  25.3  300  26 13   7.5   4.1
 15000  -3.0  26.6  290  24 12   6.8   3.7 |  -2.5  27.5  295  25 13   7.5   4.1
 14500  -1.9  28.6  290  22 11   7.1   3.9 |  -1.5  29.3  295  23 12   6.6   3.6
 14000  -0.9  30.4  290  20 10   7.2   3.9 |  -0.5  31.1  290  22 11   6.5   3.6
 13500   0.2  32.4  285  18  9   7.1   3.9 |   0.5  32.9  290  20 10   6.8   3.7
 13000   1.2  34.2  285  16  8   7.1   3.9 |   1.5  34.7  285  18  9   7.0   3.8
 12500   2.3  36.1  285  14  7   6.6   3.6 |   2.6  36.7  280  16  8   6.8   3.7
 12000   3.2  37.8  280  12  6   6.2   3.4 |   3.5  38.3  275  14  7   6.6   3.6
 11500   4.1  39.4  275  10  5   6.0   3.3 |   4.5  40.1  270  12  6   6.4   3.5
 11000   5.0  41.0  270   9  4   5.8   3.2 |   5.4  41.7  265  11  6   6.1   3.3
 10500   5.9  42.6  260   7  4   4.5   2.4 |   6.3  43.3  260  10  5   5.3   2.9
 10250   6.1  43.0  260   7  3   2.9   1.6 |   6.7  44.1  255   9  5   4.3   2.4
 10000   6.3  43.3  255   6  3   3.9   2.1 |   7.0  44.6  250   8  4   5.7   3.1
  9750   6.6  43.9  250   5  3   4.2   2.3 |   7.5  45.5  250   8  4   6.5   3.6
  9500   6.9  44.4  245   5  3   3.4   1.8 |   7.9  46.2  245   8  4   5.2   2.9
  9250   7.1  44.8  240   4  2   2.6   1.5 |   8.2  46.8  245   7  4   4.4   2.4
  9000   7.3  45.1  235   4  2   3.4   1.9 |   8.5  47.3  245   7  4   4.6   2.5
  8750   7.6  45.7  225   4  2   4.2   2.3 |   8.9  48.0  245   6  3   4.4   2.4
  8500   7.9  46.2  220   3  2   3.8   2.1 |   9.2  48.6  245   5  3   4.2   2.3
  8250   8.2  46.8  220   3  2   3.5   1.9 |   9.5  49.1  250   5  2   3.8   2.1
  8000   8.4  47.1  215   3  1   3.7   2.0 |   9.8  49.6  250   4  2   4.7   2.6
  7750   8.7  47.7  220   2  1   4.8   2.7 |  10.2  50.4  255   3  2   5.0   2.7
  7500   9.1  48.4  230   2  1   5.7   3.1 |  10.5  50.9  260   3  2   3.6   2.0
  7250   9.5  49.1  245   1  1   5.2   2.8 |  10.7  51.3  270   2  1   3.3   1.8
  7000   9.9  49.8  265   1  1   6.6   3.6 |  11.0  51.8  285   2  1   3.5   1.9
  6750  10.5  50.9  270   1  1   9.4   5.1 |  11.3  52.3  295   2  1   6.0   3.3
  6500  11.3  52.3  270   2  1  10.1   5.5 |  11.8  53.2  295   3  1   8.0   4.4
  6250  12.0  53.6  270   2  1  10.1   5.5 |  12.4  54.3  295   3  2   7.0   3.9
  6000  12.7  54.9  275   2  1   9.3   5.1 |  12.9  55.2  295   4  2   8.8   4.8
  5750  13.6  56.5  270   2  1  14.7   8.0 |  13.6  56.5  290   4  2   7.9   4.3
  5500  15.1  59.2  275   2  1  25.6  14.1 |  14.0  57.2  290   3  2   1.9   1.1
  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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