Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 121300
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0600 MST Thursday, January 12, 2017

This forecast is for Thursday, January 12, 2017:

If the trigger temperature of 46.7 F/8.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7704 ft MSL (2875 ft AGL)

Forecast maximum temperature................... 43.0 F/6.6 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
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................. 4961 ft MSL (131 ft AGL)
Thermal soaring outlook for Friday 01/13....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:32:26 / 17:12:00 MST
Total possible sunshine........... 9 hr 39 min 34 sec (579 min 34 sec)
Altitude of sun at 12:22:35 MST... 29.43 degrees

Upper air data from rawinsonde observation taken on 01/12/2017 at 0500 MST

Freezing level.................. 6267 ft MSL (1438 ft AGL)
Convective condensation level... 10005 ft MSL (5176 ft AGL)
Lifted condensation level....... 8902 ft MSL (4073 ft AGL)
Lifted index.................... +7.7
K index......................... +10.9

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  -61.3 -78.3   255   63   32   5.1   2.8  103.9 218.9    54.9      M    M
 45000  -58.6 -73.5   255   79   41   0.8   0.5   82.1 179.7    45.9      M    M
 40000  -60.8 -77.4   260  101   52   3.7   2.1   55.4 131.7    31.9      M    M
 38000  -61.6 -78.9   260   94   48  -6.0  -3.3   45.2 113.3    25.9      M    M
 36000  -62.5 -80.5   260  121   62   8.2   4.5   35.0  95.1    19.8      M    M
 34000  -57.5 -71.5   255  117   60   8.3   4.6   33.9  93.0    19.5      M    M
 32000  -52.6 -62.7   255  107   55   6.3   3.5   32.7  90.8    19.2      M    M
 30000  -48.2 -54.8   250   95   49   7.8   4.3   29.8  85.7    17.6      M    M
 29000  -45.6 -50.1   250   92   47   9.2   5.0   29.3  84.7    17.4      M    M
 28000  -42.9 -45.2   250   89   46   8.9   4.9   29.0  84.3    17.5      M    M
 27000  -40.3 -40.5   255   86   44   8.6   4.7   28.6  83.4    17.3      M    M
 26000  -38.0 -36.4   255   83   43   7.0   3.8   27.8  82.0    16.9      M    M
 25000  -35.9 -32.6   255   80   41   6.9   3.8   26.8  80.2    16.3      M    M
 24000  -33.9 -29.0   255   77   40   6.9   3.8   25.6  78.2    15.6      M    M
 23000  -32.1 -25.8   255   76   39   4.8   2.7   24.3  75.7    14.7      M    M
 22000  -30.6 -23.1   255   66   34   4.8   2.7   22.3  72.2    13.3      M    M
 21000  -29.2 -20.6   255   56   29   4.8   2.7   20.5  69.0    11.9      M    M
 20000  -27.7 -17.9   255   46   24   4.7   2.6   18.9  66.0    10.7      M    M
 19500  -27.0 -16.6   255   41   21   3.1   1.7   18.0  64.4    10.0      M    M
 19000  -27.1 -16.8   255   36   18  -0.1  -0.0   16.2  61.2     8.5      M    M
 18500  -26.4 -15.5   250   36   19   6.7   3.7   15.3  59.5     7.8      M    M
 18000  -25.5 -13.9   250   37   19   5.4   3.0   14.7  58.4     7.3      M    M
 17500  -24.4 -11.9   250   36   19   9.5   5.2   14.1  57.5     6.9      M    M
 17000  -22.9  -9.2   250   36   19   9.9   5.4   14.2  57.5     6.9      M    M
 16500  -20.7  -5.3   245   35   18  10.1   5.5   14.2  57.6     7.1      M    M
 16000  -19.3  -2.7   245   34   18   7.2   3.9   14.2  57.5     7.0      M    M
 15500  -18.4  -1.1   245   31   16   6.4   3.5   13.6  56.4     6.5      M    M
 15000  -17.5   0.5   240   27   14   6.4   3.5   13.0  55.4     6.0      M    M
 14500  -16.6   2.1   240   24   12   6.7   3.7   12.4  54.3     5.5      M    M
 14000  -15.5   4.1   235   21   11   8.4   4.6   12.1  53.8     5.2      M    M
 13500  -14.2   6.4   235   21   11   8.2   4.5   11.9  53.4     5.0      M    M
 13000  -13.0   8.6   240   20   11   8.0   4.4   11.6  52.9     4.8      M    M
 12500  -11.8  10.8   240   20   10   8.0   4.4   11.3  52.3     4.5      M    M
 12000  -10.7  12.7   240   20   10   8.1   4.5   11.0  51.9     4.3      M    M
 11500   -9.6  14.7   240   21   11   6.5   3.6   10.6  51.1     3.9      M    M
 11000   -8.6  16.5   235   23   12   6.7   3.7   10.1  50.2     3.4      M    M
 10500   -7.7  18.1   235   24   12   7.1   3.9    9.7  49.4     2.9      M    M
 10250   -7.1  19.2   235   24   13   8.0   4.4    9.5  49.1     2.8      M    M
 10000   -6.5  20.3   235   25   13   8.4   4.6    9.4  48.9     2.7      M    M
  9750   -5.9  21.4   230   22   11   8.7   4.8    9.3  48.7     2.6      M    M
  9500   -5.2  22.6   230   19   10   8.9   4.9    9.2  48.6     2.5      M    M
  9250   -4.6  23.7   225   16    8   8.6   4.7    9.2  48.5     2.4      M    M
  9000   -4.0  24.8   225   13    7   5.7   3.1    9.0  48.2     2.3      M    M
  8750   -3.7  25.3   220   11    6   3.7   2.0    8.5  47.4     1.8      M    M
  8500   -3.4  25.9   215    9    5   4.2   2.3    8.1  46.6     1.4      M    M
  8250   -3.1  26.4   205    7    4   4.1   2.2    7.7  45.8     1.0      M    M
  8000   -2.8  27.0   185    6    3   4.2   2.3    7.2  45.0     0.6      M    M
  7750   -2.5  27.5   180    5    2   4.0   2.2    6.8  44.2     0.1      M    M
  7500   -2.2  28.0   170    3    2   6.6   3.6    6.4  43.6    -0.3    178  0.9
  7250   -1.6  29.1   145    2    1   9.6   5.3    6.3  43.4    -0.4    151  0.8
  7000   -0.9  30.4   105    2    1   6.2   3.4    6.2  43.2    -0.4    125  0.6
  6750   -0.6  30.9   050    1    1   3.7   2.0    5.8  42.5    -0.9    109  0.6
  6500   -0.4  31.3   360    2    1   3.5   1.9    5.4  41.7    -1.4     93  0.5
  6250   -0.1  31.8   345    4    2   6.4   3.5    4.9  40.9    -1.8     78  0.4
  6000    0.6  33.1   335    6    3   9.5   5.2    4.9  40.8    -1.9     51  0.3
  5750    1.2  34.2   340    6    3   8.8   4.8    4.8  40.6    -2.0     23  0.1
  5500    1.9  35.4   345    5    3   8.7   4.8    4.7  40.5    -2.0      M    M
  5250    2.6  36.7   355    4    2   9.7   5.3    4.7  40.4    -2.1      M    M
  5000    3.2  37.8   010    4    2   4.5   2.5    4.6  40.2    -2.2      M    M

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

           01/12/2017 at 0800 MST          |       01/12/2017 at 1100 MST
                                           |
K index... +17.1  LI... +2.1               | K index... +17.6  LI... +1.7
CAPE... +0.8  CIN... -17.4                 | CAPE... +7.3  CIN... -5.7
                                           |
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 -62.5 -80.5  255  60 31   2.1   1.2 | -62.6 -80.7  255  60 31   2.2   1.2
 45000 -59.2 -74.6  255  70 36   2.1   1.1 | -59.2 -74.6  255  73 37   2.1   1.2
 40000 -61.0 -77.8  255  92 47  -1.8  -1.0 | -60.0 -76.0  250  88 45  -0.9  -0.5
 38000 -61.5 -78.7  255 100 51   4.0   2.2 | -60.2 -76.4  250  95 49   2.3   1.3
 36000 -59.3 -74.7  250 104 53   3.7   2.0 | -58.9 -74.0  250 102 53   2.2   1.2
 34000 -57.1 -70.8  245 108 56   3.2   1.8 | -57.6 -71.7  250 110 57   1.5   0.8
 32000 -53.0 -63.4  245 101 52   7.3   4.0 | -53.2 -63.8  250 104 54   8.0   4.4
 30000 -48.0 -54.4  250  90 47   8.5   4.7 | -47.8 -54.0  250  96 49   8.6   4.7
 29000 -45.3 -49.5  250  84 43   9.0   4.9 | -45.2 -49.4  250  90 46   8.7   4.7
 28000 -42.7 -44.9  245  78 40   9.0   4.9 | -42.6 -44.7  245  84 43   8.7   4.8
 27000 -40.0 -40.0  245  72 37   9.0   5.0 | -40.0 -40.0  245  79 41   8.7   4.8
 26000 -37.6 -35.7  245  68 35   7.3   4.0 | -37.4 -35.3  245  74 38   8.6   4.7
 25000 -35.4 -31.7  245  65 33   7.3   4.0 | -34.8 -30.6  245  69 35   8.6   4.7
 24000 -33.3 -27.9  245  61 32   7.2   4.0 | -32.3 -26.1  245  64 33   8.6   4.7
 23000 -31.4 -24.5  245  58 30   5.5   3.0 | -30.3 -22.5  240  59 30   5.0   2.7
 22000 -29.8 -21.6  245  53 28   5.4   3.0 | -28.9 -20.0  240  53 27   4.9   2.7
 21000 -28.1 -18.6  250  49 25   5.3   2.9 | -27.4 -17.3  240  47 24   4.8   2.6
 20000 -26.4 -15.5  250  46 24   6.1   3.4 | -25.8 -14.4  240  43 22   5.5   3.0
 19500 -25.5 -13.9  250  45 23   6.1   3.4 | -25.0 -13.0  235  43 22   5.5   3.0
 19000 -24.6 -12.3  250  43 22   6.1   3.4 | -24.2 -11.6  235  42 21   5.5   3.0
 18500 -23.7 -10.7  250  41 21   6.2   3.4 | -23.3  -9.9  235  41 21   5.4   3.0
 18000 -22.8  -9.0  250  40 21   5.7   3.1 | -22.5  -8.5  235  40 21   6.6   3.6
 17500 -21.9  -7.4  250  39 20   5.7   3.1 | -21.5  -6.7  230  39 20   6.6   3.6
 17000 -21.1  -6.0  250  38 20   5.8   3.2 | -20.5  -4.9  230  39 20   6.3   3.4
 16500 -20.2  -4.4  245  37 19   6.1   3.3 | -19.6  -3.3  230  37 19   5.9   3.3
 16000 -19.3  -2.7  245  35 18   6.1   3.3 | -18.8  -1.8  230  36 18   5.9   3.2
 15500 -18.4  -1.1  245  33 17   5.6   3.1 | -17.9  -0.2  225  34 17   5.7   3.1
 15000 -17.6   0.3  245  31 16   5.6   3.0 | -17.1   1.2  225  31 16   5.7   3.1
 14500 -16.7   1.9  240  29 15   6.7   3.7 | -15.7   3.7  220  27 14   6.4   3.5
 14000 -15.2   4.6  240  26 14   6.9   3.8 | -14.7   5.5  215  25 13   6.9   3.8
 13500 -14.1   6.6  235  26 13   7.6   4.2 | -13.6   7.5  215  22 11   8.1   4.5
 13000 -13.0   8.6  235  25 13   7.8   4.3 | -12.4   9.7  210  19 10   8.1   4.4
 12500 -11.7  10.9  235  24 12   8.9   4.9 | -11.3  11.7  205  18  9   8.0   4.4
 12000 -10.4  13.3  230  23 12   8.8   4.8 | -10.1  13.8  205  18  9   7.8   4.3
 11500  -9.2  15.4  230  21 11   8.5   4.6 |  -9.0  15.8  200  18  9   7.0   3.9
 11000  -8.0  17.6  230  20 10   7.7   4.2 |  -8.0  17.6  200  18  9   6.9   3.8
 10500  -7.2  19.0  230  17  9   4.9   2.7 |  -7.0  19.4  195  18  9   6.3   3.5
 10250  -6.8  19.8  230  16  8   5.1   2.8 |  -6.5  20.3  195  18  9   7.0   3.8
 10000  -6.4  20.5  230  15  7   7.3   4.0 |  -6.0  21.2  190  18  9   8.4   4.6
  9750  -5.8  21.6  225  13  7   7.5   4.1 |  -5.4  22.3  190  17  9   7.5   4.1
  9500  -5.4  22.3  225  12  6   6.1   3.3 |  -4.9  23.2  190  17  9   6.6   3.6
  9250  -4.9  23.2  225  11  5   6.4   3.5 |  -4.4  24.1  185  16  8   6.7   3.7
  9000  -4.5  23.9  225   9  5   5.4   3.0 |  -3.9  25.0  185  16  8   6.0   3.3
  8750  -4.1  24.6  220   8  4   5.4   2.9 |  -3.5  25.7  185  15  8   6.1   3.3
  8500  -3.7  25.3  215   8  4   5.9   3.3 |  -3.0  26.6  185  15  8   6.3   3.5
  8250  -3.2  26.2  210   7  4   5.6   3.1 |  -2.6  27.3  180  14  7   6.7   3.7
  8000  -2.9  26.8  205   6  3   5.1   2.8 |  -2.0  28.4  180  14  7   7.2   4.0
  7750  -2.5  27.5  195   6  3   4.8   2.7 |  -1.5  29.3  180  14  7   6.5   3.6
  7500  -2.1  28.2  185   6  3   4.9   2.7 |  -1.1  30.0  175  13  7   6.2   3.4
  7250  -1.8  28.8  180   6  3   4.4   2.4 |  -0.6  30.9  175  13  7   5.4   2.9
  7000  -1.5  29.3  170   6  3   4.0   2.2 |  -0.3  31.5  170  13  6   4.4   2.4
  6750  -1.2  29.8  165   6  3   3.9   2.2 |   0.0  32.0  160  12  6   3.2   1.7
  6500  -0.9  30.4  155   6  3   4.0   2.2 |   0.2  32.4  155  11  5   3.8   2.1
  6250  -0.6  30.9  150   6  3   4.0   2.2 |   0.6  33.1  150   9  5   6.2   3.4
  6000  -0.3  31.5  150   6  3   4.6   2.5 |   1.0  33.8  140   8  4   6.3   3.5
  5750   0.1  32.2  140   6  3   4.4   2.4 |   1.5  34.7  130   6  3   5.8   3.2
  5500   0.3  32.5  130   5  2   0.7   0.4 |   1.9  35.4  125   5  2   4.9   2.7
  5250   0.1  32.2  130   4  2  -3.0  -1.6 |   2.2  36.0  120   5  2   4.5   2.5
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/12/2017 at 1400 MST          |       01/12/2017 at 1700 MST
                                           |
K index... +17.9  LI... +1.7               | K index... +17.0  LI... +2.3
CAPE... 0.0  CIN... -16.1                  | CAPE... +28.6  CIN... -7.0
                                           |
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 -63.2 -81.8  255  65 33   2.1   1.1 | -62.2 -80.0  255  63 32   1.4   0.7
 45000 -59.9 -75.8  255  77 40   2.0   1.1 | -60.2 -76.4  255  75 38   1.3   0.7
 40000 -61.4 -78.5  250  95 49  -1.4  -0.8 | -62.3 -80.1  250  96 50  -1.8  -1.0
 38000 -61.7 -79.1  250 102 53   3.5   1.9 | -62.5 -80.5  245 105 54   4.7   2.6
 36000 -59.6 -75.3  245 106 55   3.5   1.9 | -59.7 -75.5  245 108 55   4.7   2.6
 34000 -57.5 -71.5  245 111 57   3.8   2.1 | -56.9 -70.4  240 111 57   5.0   2.8
 32000 -52.3 -62.1  240 104 54   9.2   5.0 | -51.2 -60.2  240 104 54   8.7   4.8
 30000 -46.1 -51.0  240  96 49   8.5   4.7 | -46.0 -50.8  240  98 50   8.4   4.6
 29000 -43.6 -46.5  240  93 48   8.2   4.5 | -43.5 -46.3  240  94 48   8.2   4.5
 28000 -41.2 -42.2  240  91 47   8.2   4.5 | -41.0 -41.8  240  91 47   8.2   4.5
 27000 -38.7 -37.7  240  88 45   8.3   4.5 | -38.6 -37.5  240  87 45   8.3   4.6
 26000 -36.4 -33.5  240  83 42   7.6   4.2 | -36.3 -33.3  240  82 42   7.2   4.0
 25000 -34.1 -29.4  240  76 39   7.6   4.2 | -34.2 -29.6  240  76 39   7.2   4.0
 24000 -31.9 -25.4  240  69 35   7.6   4.2 | -32.0 -25.6  240  70 36   7.3   4.0
 23000 -29.8 -21.6  240  64 33   6.5   3.5 | -30.0 -22.0  240  65 33   6.2   3.4
 22000 -27.9 -18.2  240  60 31   6.4   3.5 | -28.2 -18.8  240  59 30   6.2   3.4
 21000 -26.0 -14.8  240  57 29   6.8   3.7 | -26.3 -15.3  240  54 28   6.2   3.4
 20000 -24.5 -12.1  240  50 26   4.2   2.3 | -24.6 -12.3  240  49 25   5.7   3.1
 19500 -23.9 -11.0  240  47 24   4.2   2.3 | -23.8 -10.8  240  46 24   5.7   3.1
 19000 -23.3  -9.9  240  43 22   4.2   2.3 | -22.9  -9.2  240  44 23   5.7   3.1
 18500 -22.6  -8.7  235  39 20   4.2   2.3 | -22.1  -7.8  240  41 21   5.7   3.1
 18000 -22.0  -7.6  235  36 19   4.9   2.7 | -21.2  -6.2  240  39 20   5.7   3.1
 17500 -21.3  -6.3  235  34 17   4.9   2.7 | -20.4  -4.7  240  38 20   5.7   3.1
 17000 -20.5  -4.9  240  32 16   5.7   3.1 | -19.5  -3.1  240  36 19   5.3   2.9
 16500 -19.6  -3.3  240  30 15   6.6   3.6 | -18.8  -1.8  240  36 18   5.0   2.7
 16000 -18.6  -1.5  240  28 15   6.7   3.7 | -18.1  -0.6  240  35 18   5.1   2.8
 15500 -17.5   0.5  235  27 14   7.5   4.1 | -17.2   1.0  240  34 17   6.5   3.6
 15000 -15.9   3.4  235  25 13   7.4   4.1 | -15.8   3.6  235  32 17   6.2   3.4
 14500 -14.8   5.4  230  24 12   7.4   4.1 | -14.9   5.2  235  31 16   5.9   3.3
 14000 -13.7   7.3  225  24 12   7.3   4.0 | -14.0   6.8  235  30 15   5.9   3.2
 13500 -12.7   9.1  220  25 13   7.0   3.8 | -13.2   8.2  235  27 14   5.8   3.2
 13000 -11.6  11.1  220  26 14   7.0   3.9 | -12.3   9.9  235  25 13   6.1   3.3
 12500 -10.6  12.9  215  29 15   7.3   4.0 | -11.3  11.7  235  26 14   7.2   3.9
 12000  -9.5  14.9  215  31 16   7.4   4.1 | -10.2  13.6  240  29 15   7.3   4.0
 11500  -8.3  17.1  210  33 17   8.2   4.5 |  -9.1  15.6  240  29 15   8.1   4.4
 11000  -7.1  19.2  210  34 18   7.8   4.3 |  -7.9  17.8  235  28 14   7.9   4.3
 10500  -6.1  21.0  205  36 19   6.0   3.3 |  -6.8  19.8  235  27 14   6.9   3.8
 10250  -5.7  21.7  205  37 19   6.9   3.8 |  -6.3  20.7  230  27 14   8.6   4.7
 10000  -5.1  22.8  205  38 19   8.6   4.7 |  -5.6  21.9  230  26 14  10.2   5.6
  9750  -4.5  23.9  205  37 19   7.7   4.2 |  -4.9  23.2  225  26 14   8.5   4.7
  9500  -4.0  24.8  200  36 18   6.7   3.6 |  -4.3  24.3  220  27 14   7.7   4.2
  9250  -3.5  25.7  200  35 18   6.9   3.8 |  -3.7  25.3  220  27 14   7.9   4.4
  9000  -3.0  26.6  200  33 17   6.5   3.6 |  -3.2  26.2  215  27 14   7.9   4.3
  8750  -2.5  27.5  200  31 16   6.8   3.7 |  -2.6  27.3  215  27 14   7.9   4.4
  8500  -2.0  28.4  195  29 15   7.2   4.0 |  -2.0  28.4  210  27 14   7.8   4.3
  8250  -1.5  29.3  195  27 14   7.0   3.8 |  -1.4  29.5  210  26 14   8.3   4.5
  8000  -1.0  30.2  190  25 13   5.9   3.3 |  -0.8  30.6  205  26 13   8.8   4.8
  7750  -0.6  30.9  190  23 12   5.0   2.7 |  -0.2  31.6  205  24 13   8.2   4.5
  7500  -0.3  31.5  185  21 11   4.7   2.6 |   0.4  32.7  200  23 12   7.8   4.3
  7250   0.0  32.0  180  20 10   5.1   2.8 |   1.0  33.8  200  22 11   8.5   4.7
  7000   0.4  32.7  175  18  9   5.7   3.1 |   1.6  34.9  195  21 11   8.6   4.7
  6750   0.9  33.6  170  16  8   6.2   3.4 |   2.2  36.0  190  20 10   6.9   3.8
  6500   1.3  34.3  165  14  7   7.2   4.0 |   2.7  36.9  185  19 10   5.1   2.8
  6250   1.9  35.4  160  12  6   8.3   4.5 |   3.0  37.4  180  17  9   3.8   2.1
  6000   2.5  36.5  160  10  5   8.5   4.7 |   3.2  37.8  175  16  8   3.5   1.9
  5750   3.1  37.6  155   9  4   7.3   4.0 |   3.4  38.1  165  13  7   1.1   0.6
  5500   3.5  38.3  155   7  4   4.8   2.6 |   3.3  37.9  160  10  5  -3.4  -1.9
  5250   3.8  38.8  150   6  3   2.9   1.6 |   2.9  37.2  155   9  4  -5.7  -3.1
  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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