Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 191230
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0530 MST Sunday, February 19, 2017

This forecast is for Sunday, February 19, 2017:

If the trigger temperature of 57.2 F/14.0 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6459 ft MSL (1620 ft AGL)

Forecast maximum temperature................... 52.0 F/11.6 C
Time of trigger temperature.................... 1430 MST
Time of overdevelopment........................ 0800 MST
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5700 ft MSL (861 ft AGL)
Thermal soaring outlook for Monday 02/20....... Fair

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

Remarks...

Sunrise/Sunset.................... 06:59:58 / 17:55:02 MST
Total possible sunshine........... 10 hr 55 min 4 sec (655 min 4 sec)
Altitude of sun at 12:27:47 MST... 39.92 degrees

Upper air data from rawinsonde observation taken on 02/19/2017 at 0500 MST

Freezing level.................. 9667 ft MSL (4828 ft AGL)
Convective condensation level... 11740 ft MSL (6901 ft AGL)
Lifted condensation level....... 10018 ft MSL (5178 ft AGL)
Lifted index.................... +4.7
K index......................... +19.8

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -56.7 -70.1   220   41   21   6.7   3.7  106.1 222.9    54.2      M    M
 45000  -51.3 -60.3   215   51   26   5.0   2.8   89.2 192.5    47.8      M    M
 40000  -47.2 -53.0   220   42   22  -6.1  -3.3   72.7 162.8    40.2      M    M
 38000  -49.6 -57.3   215   36   19  -8.2  -4.5   60.2 140.4    33.0      M    M
 36000  -46.4 -51.5   200   53   27   7.0   3.8   56.3 133.3    31.1      M    M
 34000  -48.4 -55.1   185   58   30 -10.4  -5.7   45.2 113.4    24.1      M    M
 32000  -51.3 -60.3   190   44   23  -5.7  -3.1   32.0  89.5    15.2      M    M
 30000  -47.9 -54.2   195   41   21   9.2   5.1   28.5  83.3    13.0      M    M
 29000  -45.1 -49.2   195   41   21   9.4   5.2   28.2  82.7    12.9      M    M
 28000  -42.3 -44.1   195   41   21   9.4   5.2   28.0  82.4    12.9      M    M
 27000  -39.5 -39.1   195   42   21   9.4   5.2   27.9  82.2    13.0      M    M
 26000  -36.7 -34.1   195   42   22   9.5   5.2   27.9  82.2    13.2      M    M
 25000  -34.1 -29.4   195   42   22   8.4   4.6   27.6  81.7    13.1      M    M
 24000  -31.6 -24.9   200   46   24   8.6   4.7   27.1  80.7    12.8      M    M
 23000  -28.9 -20.0   205   42   22   8.6   4.7   26.8  80.2    12.7      M    M
 22000  -26.3 -15.3   210   41   21   9.0   4.9   26.4  79.5    12.6      M    M
 21000  -24.2 -11.6   215   41   21   2.3   1.3   25.5  77.8    11.9      M    M
 20000  -22.8  -9.0   200   34   17   8.3   4.6   23.8  74.8    10.5      M    M
 19500  -21.5  -6.7   200   31   16   8.5   4.7   23.6  74.4    10.4      M    M
 19000  -20.2  -4.4   195   28   15   7.7   4.2   23.4  74.1    10.3      M    M
 18500  -19.3  -2.7   195   28   14   6.4   3.5   22.8  73.0     9.8      M    M
 18000  -18.4  -1.1   195   27   14   5.0   2.8   22.1  71.8     9.3      M    M
 17500  -17.7   0.1   200   26   13   6.5   3.6   21.3  70.3     8.6      M    M
 17000  -15.9   3.4   205   25   13   8.0   4.4   20.8  69.4     8.2      M    M
 16500  -14.7   5.5   210   24   12   8.0   4.4   20.5  68.9     8.0      M    M
 16000  -13.6   7.5   215   23   12   8.0   4.4   20.2  68.4     7.8      M    M
 15500  -12.4   9.7   210   26   13   6.3   3.5   19.9  67.8     7.5      M    M
 15000  -11.6  11.1   210   28   15   5.3   2.9   19.1  66.4     6.9      M    M
 14500  -10.9  12.4   205   31   16   2.4   1.3   18.4  65.0     6.2      M    M
 14000  -10.8  12.6   205   33   17   5.8   3.2   16.9  62.5     4.9      M    M
 13500   -9.5  14.9   205   32   16   8.3   4.6   16.7  62.1     4.7      M    M
 13000   -8.3  17.1   205   31   16   8.5   4.7   16.5  61.7     4.5      M    M
 12500   -7.0  19.4   205   30   15   8.5   4.7   16.3  61.4     4.4      M    M
 12000   -5.7  21.7   205   29   15   8.6   4.7   16.2  61.1     4.2      M    M
 11500   -4.5  23.9   205   30   15   8.6   4.7   16.0  60.7     4.0      M    M
 11000   -3.2  26.2   200   30   16   8.6   4.7   15.7  60.3     3.8      M    M
 10500   -1.9  28.6   200   31   16   8.7   4.8   15.6  60.0     3.7      M    M
 10250   -1.3  29.7   200   32   16   8.0   4.4   15.5  59.9     3.6      M    M
 10000   -0.8  30.6   200   32   16   7.3   4.0   15.3  59.5     3.4      M    M
  9750   -0.2  31.6   200   27   14   7.8   4.3   15.1  59.2     3.2      M    M
  9500    0.4  32.7   200   24   12   8.0   4.4   15.0  59.0     3.1      M    M
  9250    1.0  33.8   200   21   11   7.9   4.3   14.8  58.7     3.0      M    M
  9000    1.5  34.7   200   18    9   7.9   4.4   14.7  58.5     2.8      M    M
  8750    2.1  35.8   200   16    8   7.9   4.4   14.6  58.2     2.7      M    M
  8500    2.7  36.9   205   14    7   7.9   4.4   14.4  58.0     2.6      M    M
  8250    3.3  37.9   205   12    6   7.9   4.4   14.3  57.7     2.4      M    M
  8000    3.9  39.0   210   10    5   7.9   4.4   14.2  57.5     2.3      M    M
  7750    4.5  40.1   205   10    5   8.0   4.4   14.0  57.2     2.1      M    M
  7500    5.0  41.0   205   10    5   7.9   4.3   13.8  56.9     2.0      M    M
  7250    5.6  42.1   200   11    5   8.2   4.5   13.7  56.7     1.9      M    M
  7000    6.2  43.2   195   11    6   7.0   3.9   13.6  56.4     1.7      M    M
  6750    6.7  44.1   180   12    6   6.2   3.4   13.3  55.9     1.4      M    M
  6500    6.7  44.1   170   14    7  -9.0  -4.9   12.7  54.8     0.8      M    M
  6250    5.6  42.1   160   16    8 -10.6  -5.8   10.8  51.4    -1.1     81  0.4
  6000    5.4  41.7   150   19   10   2.1   1.1    9.9  49.9    -2.0     78  0.4
  5750    5.5  41.9   145   18    9   0.7   0.4    9.3  48.7    -2.7     69  0.3
  5500    5.6  42.1   145   15    8   1.5   0.8    8.6  47.5    -3.3     60  0.3
  5250    5.5  41.9   135   12    6  -5.7  -3.2    7.8  46.0    -4.2     55  0.3
  5000    4.7  40.5   125   10    5 -13.4  -7.4    6.3  43.3    -5.7     71  0.4

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

           02/19/2017 at 0800 MST          |       02/19/2017 at 1100 MST
                                           |
K index... +21.5  LI... +2.0               | K index... +21.6  LI... +1.3
CAPE... 0.0  CIN... -1.0                   | CAPE... 0.0  CIN... -0.9
                                           |
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 -57.0 -70.6  240  33 17   4.6   2.5 | -57.5 -71.5  250  27 14   4.5   2.5
 45000 -49.9 -57.8  230  37 19   2.3   1.3 | -50.5 -58.9  250  32 16   2.8   1.5
 40000 -46.7 -52.1  220  32 16   2.1   1.2 | -46.4 -51.5  240  29 15   2.7   1.5
 38000 -46.3 -51.3  215  33 17  -1.4  -0.8 | -45.7 -50.3  225  29 15  -1.2  -0.7
 36000 -47.2 -53.0  205  38 20  -1.4  -0.8 | -46.4 -51.5  205  34 18  -1.2  -0.6
 34000 -48.0 -54.4  200  44 23  -1.1  -0.6 | -47.1 -52.8  190  42 22  -0.6  -0.3
 32000 -48.2 -54.8  195  62 32  -0.2  -0.1 | -46.6 -51.9  180  60 31   0.9   0.5
 30000 -47.8 -54.0  195  80 41   9.0   5.0 | -45.7 -50.3  175  81 42   7.4   4.1
 29000 -45.1 -49.2  190  74 38   9.3   5.1 | -43.3 -45.9  175  81 42   8.2   4.5
 28000 -42.3 -44.1  190  68 35   9.3   5.1 | -40.8 -41.4  175  81 42   8.2   4.5
 27000 -39.5 -39.1  190  63 32   9.3   5.1 | -38.3 -36.9  175  81 42   8.3   4.6
 26000 -36.8 -34.2  190  57 29   9.0   4.9 | -36.1 -33.0  175  78 40   7.3   4.0
 25000 -34.1 -29.4  190  51 26   9.0   5.0 | -33.9 -29.0  175  73 38   7.3   4.0
 24000 -31.4 -24.5  190  46 23   9.1   5.0 | -31.6 -24.9  175  69 35   7.3   4.0
 23000 -29.0 -20.2  185  39 20   7.4   4.1 | -29.4 -20.9  175  64 33   7.4   4.0
 22000 -26.8 -16.2  185  33 17   7.4   4.1 | -27.2 -17.0  175  59 30   7.4   4.0
 21000 -24.6 -12.3  180  27 14   7.4   4.1 | -25.0 -13.0  175  54 28   7.5   4.1
 20000 -22.2  -8.0  185  28 14   8.4   4.6 | -23.1  -9.6  175  48 25   6.4   3.5
 19500 -20.9  -5.6  185  29 15   8.4   4.6 | -22.1  -7.8  175  45 23   6.4   3.5
 19000 -19.7  -3.5  185  30 16   8.4   4.6 | -21.2  -6.2  180  42 21   6.4   3.5
 18500 -18.5  -1.3  190  32 16   8.5   4.7 | -20.2  -4.4  180  39 20   6.3   3.5
 18000 -17.3   0.9  190  32 17   6.8   3.7 | -19.2  -2.6  185  36 18   7.2   4.0
 17500 -16.3   2.7  195  31 16   6.9   3.8 | -18.2  -0.8  185  33 17   7.3   4.0
 17000 -15.3   4.5  195  30 16   6.8   3.7 | -17.1   1.2  185  30 16   7.2   3.9
 16500 -14.3   6.3  195  30 16   6.8   3.7 | -16.1   3.0  190  29 15   6.8   3.7
 16000 -13.3   8.1  200  30 16   6.8   3.7 | -15.1   4.8  190  28 14   6.8   3.7
 15500 -12.4   9.7  200  31 16   5.7   3.1 | -14.1   6.6  195  26 14   7.4   4.1
 15000 -11.6  11.1  200  31 16   5.8   3.2 | -13.0   8.6  195  26 13   7.6   4.1
 14500 -10.8  12.6  200  31 16   5.0   2.7 | -12.0  10.4  195  25 13   6.1   3.4
 14000  -9.7  14.5  195  30 16   5.0   2.7 | -10.7  12.7  195  26 13   6.0   3.3
 13500  -8.9  16.0  200  29 15   5.2   2.8 |  -9.9  14.2  195  25 13   5.5   3.0
 13000  -8.2  17.2  200  28 14   5.1   2.8 |  -9.1  15.6  195  22 12   5.3   2.9
 12500  -7.3  18.9  200  26 13   6.5   3.5 |  -8.1  17.4  195  21 11   7.7   4.2
 12000  -6.4  20.5  200  23 12   6.3   3.4 |  -7.0  19.4  195  21 11   7.7   4.2
 11500  -5.4  22.3  205  21 11   7.8   4.3 |  -6.0  21.2  195  20 10   5.8   3.2
 11000  -4.3  24.3  205  18 10   7.7   4.2 |  -5.2  22.6  200  19 10   6.0   3.3
 10500  -3.2  26.2  200  16  8   7.6   4.2 |  -4.2  24.4  200  18  9   6.8   3.7
 10250  -2.7  27.1  200  15  8   8.0   4.4 |  -3.7  25.3  200  17  9   6.9   3.8
 10000  -2.0  28.4  200  15  8   8.9   4.9 |  -3.2  26.2  205  17  8   7.3   4.0
  9750  -1.4  29.5  200  14  7   8.6   4.7 |  -2.6  27.3  205  16  8   7.6   4.2
  9500  -0.7  30.7  200  14  7   8.1   4.4 |  -2.1  28.2  205  16  8   7.6   4.2
  9250  -0.1  31.8  200  13  7   8.3   4.6 |  -1.5  29.3  210  16  8   7.8   4.3
  9000   0.5  32.9  200  13  6   7.4   4.1 |  -1.0  30.2  210  17  9   6.6   3.6
  8750   1.0  33.8  200  12  6   6.9   3.8 |  -0.5  31.1  210  16  8   6.2   3.4
  8500   1.5  34.7  200  12  6   7.3   4.0 |  -0.0  32.0  215  16  8   7.1   3.9
  8250   2.1  35.8  200  11  6   7.3   4.0 |   0.5  32.9  215  16  8   6.6   3.6
  8000   2.6  36.7  200  11  6   6.9   3.8 |   1.0  33.8  220  15  8   7.7   4.2
  7750   3.1  37.6  195  10  5   5.2   2.8 |   1.6  34.9  220  14  7   7.2   3.9
  7500   3.4  38.1  190  10  5   4.3   2.4 |   2.0  35.6  220  13  7   5.7   3.1
  7250   3.8  38.8  185  10  5   4.5   2.4 |   2.5  36.5  220  11  6   6.1   3.4
  7000   4.1  39.4  175  10  5   3.7   2.0 |   3.0  37.4  220  10  5   6.6   3.6
  6750   4.3  39.7  170  10  5   2.7   1.5 |   3.5  38.3  215   9  4   7.4   4.0
  6500   4.5  40.1  160  10  5   4.1   2.3 |   4.0  39.2  215   7  4   7.1   3.9
  6250   4.8  40.6  155   9  5  -0.9  -0.5 |   4.5  40.1  215   5  3   8.5   4.7
  6000   4.4  39.9  145   8  4  -7.0  -3.9 |   5.3  41.5  215   5  3  10.1   5.5
  5750   3.9  39.0  130   7  3  -5.1  -2.8 |   6.0  42.8  215   5  2   9.6   5.3
  5500   3.5  38.3  095   5  3  -6.7  -3.7 |   6.7  44.1  215   4  2   9.1   5.0
  5250   2.7  36.9  075   5  3 -13.0  -7.2 |   7.3  45.1  220   4  2   8.1   4.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           02/19/2017 at 1400 MST          |       02/19/2017 at 1700 MST
                                           |
K index... +23.7  LI... +1.3               | K index... +24.6  LI... +1.2
CAPE... +0.8  CIN... -0.2                  | CAPE... +0.8  CIN... -0.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -57.4 -71.3  245  28 15   4.6   2.5 | -58.1 -72.6  260  24 12   4.1   2.2
 45000 -50.3 -58.5  250  30 16   3.2   1.8 | -51.7 -61.1  295  26 14   4.2   2.3
 40000 -45.5 -49.9  260  30 15   3.2   1.7 | -45.4 -49.7  300  36 18   4.2   2.3
 38000 -44.1 -47.4  260  28 14   1.3   0.7 | -43.7 -46.7  300  37 19   1.4   0.8
 36000 -43.3 -45.9  250  25 13   1.3   0.7 | -42.9 -45.2  300  36 19   1.4   0.8
 34000 -42.5 -44.5  240  22 11   1.0   0.5 | -42.1 -43.8  300  35 18   1.1   0.6
 32000 -42.9 -45.2  230  25 13  -0.6  -0.4 | -41.7 -43.1  300  34 18   0.5   0.3
 30000 -43.2 -45.8  225  28 14   0.6   0.3 | -41.3 -42.3  295  33 17  -0.1  -0.0
 29000 -42.8 -45.0  225  27 14   1.6   0.9 | -41.5 -42.7  295  29 15  -0.5  -0.3
 28000 -42.3 -44.1  225  26 13   1.6   0.9 | -41.7 -43.1  295  25 13  -0.5  -0.3
 27000 -41.8 -43.2  225  24 13   1.5   0.8 | -41.8 -43.2  295  22 11  -0.7  -0.4
 26000 -40.0 -40.0  225  22 11   9.1   5.0 | -40.3 -40.5  290  19 10   8.8   4.8
 25000 -37.2 -35.0  225  19 10   9.3   5.1 | -37.7 -35.9  280  17  9   9.0   4.9
 24000 -34.4 -29.9  220  16  8   9.3   5.1 | -35.0 -31.0  270  16  8   9.0   4.9
 23000 -31.8 -25.2  210  15  8   8.3   4.6 | -32.3 -26.1  265  16  8   8.7   4.8
 22000 -29.4 -20.9  205  17  9   8.3   4.5 | -29.7 -21.5  260  17  9   8.7   4.8
 21000 -26.9 -16.4  195  19 10   8.3   4.6 | -27.1 -16.8  260  18  9   8.9   4.9
 20000 -24.5 -12.1  195  21 11   8.0   4.4 | -24.8 -12.6  265  18  9   7.5   4.1
 19500 -23.3  -9.9  195  21 11   8.0   4.4 | -23.7 -10.7  265  18  9   7.5   4.1
 19000 -22.1  -7.8  195  22 11   8.0   4.4 | -22.6  -8.7  270  18  9   7.5   4.1
 18500 -20.9  -5.6  190  22 11   8.1   4.4 | -21.5  -6.7  270  18  9   7.6   4.2
 18000 -19.8  -3.6  190  23 12   7.3   4.0 | -20.4  -4.7  275  19 10   6.9   3.8
 17500 -18.7  -1.7  195  22 11   7.2   4.0 | -19.4  -2.9  280  19 10   6.9   3.8
 17000 -17.6   0.3  195  22 11   7.1   3.9 | -18.4  -1.1  280  20 10   6.9   3.8
 16500 -16.6   2.1  200  22 11   6.9   3.8 | -17.3   0.9  285  20 11   7.0   3.9
 16000 -15.6   3.9  205  21 11   6.9   3.8 | -16.3   2.7  285  21 11   7.0   3.9
 15500 -14.6   5.7  205  21 11   6.5   3.6 | -15.2   4.6  285  21 11   7.2   3.9
 15000 -13.2   8.2  210  20 10   6.6   3.6 | -13.7   7.3  285  21 11   7.0   3.9
 14500 -12.2  10.0  215  20 10   6.9   3.8 | -12.7   9.1  285  21 11   6.7   3.7
 14000 -11.2  11.8  215  19 10   6.9   3.8 | -11.7  10.9  285  21 11   6.7   3.7
 13500 -10.2  13.6  215  19 10   6.5   3.5 | -10.7  12.7  280  20 11   6.6   3.6
 13000  -9.3  15.3  220  19 10   6.5   3.6 |  -9.7  14.5  280  20 10   6.6   3.6
 12500  -8.3  17.1  220  19 10   6.4   3.5 |  -8.8  16.2  280  20 10   6.0   3.3
 12000  -7.4  18.7  220  19 10   6.4   3.5 |  -7.9  17.8  275  20 10   6.1   3.3
 11500  -6.5  20.3  220  19 10   6.2   3.4 |  -7.0  19.4  275  20 10   6.6   3.6
 11000  -5.6  21.9  220  18  9   6.3   3.4 |  -6.1  21.0  275  20 10   6.6   3.6
 10500  -4.7  23.5  220  18  9   5.6   3.1 |  -5.2  22.6  270  20 10   5.4   3.0
 10250  -4.3  24.3  220  17  9   6.1   3.3 |  -4.8  23.4  270  20 10   5.9   3.2
 10000  -3.8  25.2  215  17  9   7.2   4.0 |  -4.3  24.3  265  20 10   7.2   4.0
  9750  -3.3  26.1  215  17  9   6.6   3.6 |  -3.8  25.2  265  20 10   6.8   3.8
  9500  -2.9  26.8  215  17  9   5.4   3.0 |  -3.3  26.1  265  19 10   5.8   3.2
  9250  -2.5  27.5  215  17  9   5.9   3.3 |  -2.9  26.8  265  19 10   6.2   3.4
  9000  -2.1  28.2  215  16  8   5.1   2.8 |  -2.5  27.5  260  19 10   5.6   3.1
  8750  -1.7  28.9  215  16  8   4.8   2.6 |  -2.1  28.2  260  18  9   5.0   2.7
  8500  -1.4  29.5  215  16  8   5.3   2.9 |  -1.7  28.9  260  18  9   5.0   2.8
  8250  -1.0  30.2  210  16  8   5.1   2.8 |  -1.4  29.5  260  17  9   5.1   2.8
  8000  -0.6  30.9  210  16  8   5.2   2.9 |  -1.0  30.2  260  17  9   4.9   2.7
  7750  -0.2  31.6  205  15  8   5.6   3.1 |  -0.7  30.7  265  16  8   3.7   2.1
  7500   0.2  32.4  200  14  7   5.7   3.1 |  -0.4  31.3  265  15  8   3.1   1.7
  7250   0.6  33.1  200  13  7   6.4   3.5 |  -0.2  31.6  270  14  7   3.6   2.0
  7000   1.2  34.2  195  13  7   9.3   5.1 |   0.1  32.2  270  13  7   5.1   2.8
  6750   1.9  35.4  195  12  6  10.3   5.6 |   0.5  32.9  270  12  6   7.3   4.0
  6500   2.7  36.9  195  12  6   9.6   5.3 |   1.1  34.0  275  11  6   8.1   4.5
  6250   3.4  38.1  195  12  6  10.2   5.6 |   1.7  35.1  275  10  5   9.5   5.2
  6000   4.2  39.6  195  11  6  10.3   5.6 |   2.5  36.5  275   9  5  10.6   5.8
  5750   4.9  40.8  190  10  5   9.6   5.2 |   3.2  37.8  275   8  4  10.4   5.7
  5500   5.6  42.1  190   9  5   8.7   4.8 |   3.9  39.0  280   7  4   8.4   4.6
  5250   6.2  43.2  195   9  5   7.7   4.2 |   4.4  39.9  275   7  4   3.6   2.0
  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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