Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 131257
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0657 MDT Friday, October 13, 2017

This forecast is for Friday, October 13, 2017:

If the trigger temperature of 64.6 F/18.1 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 609 ft/min (3.1 m/s)
   Maximum height of thermals.................. 12576 ft MSL (7737 ft AGL)

Forecast maximum temperature................... 71.0 F/22.1 C
Time of trigger temperature.................... 1200 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................. 9867 ft MSL (5027 ft AGL)
Thermal soaring outlook for Saturday 10/14..... Good

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

Remarks...

Sunrise/Sunset.................... 07:22:08 / 18:39:22 MDT
Total possible sunshine........... 11 hr 17 min 13 sec (677 min 13 sec)
Altitude of sun at 13:00:18 MDT... 42.84 degrees

Upper air data from rawinsonde observation taken on 10/13/2017 at 0600 MDT

Freezing level.................. 11998 ft MSL (7159 ft AGL)
Convective condensation level... 20919 ft MSL (16080 ft AGL)
Lifted condensation level....... 17627 ft MSL (12788 ft AGL)
Lifted index.................... +7.8
K index......................... -1.9

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  -63.5 -82.3   240   93   48   3.6   2.0   92.3 198.2    40.5      M    M
 45000  -59.3 -74.7   250  111   57   1.4   0.7   73.7 164.7    32.1      M    M
 40000  -55.1 -67.2   250  126   65   6.5   3.5   57.3 135.1    23.5      M    M
 38000  -51.4 -60.5   250  127   66   6.8   3.8   54.1 129.3    22.0      M    M
 36000  -47.2 -53.0   250  120   62   7.3   4.0   51.7 125.0    20.9      M    M
 34000  -42.8 -45.0   250  113   58   5.0   2.8   49.7 121.4    20.0      M    M
 32000  -40.2 -40.4   250  105   54   6.5   3.6   45.3 113.6    17.3      M    M
 30000  -34.7 -30.5   250  100   51   8.9   4.9   43.8 110.9    16.7      M    M
 29000  -32.7 -26.9   250   98   50   4.4   2.4   42.6 108.6    15.9      M    M
 28000  -31.0 -23.8   245   95   49   7.1   3.9   41.0 105.7    14.8      M    M
 27000  -28.9 -20.0   245   93   48   7.3   4.0   40.0 104.0    14.3      M    M
 26000  -26.7 -16.1   245   91   47   8.6   4.7   39.0 102.2    13.7      M    M
 25000  -25.4 -13.7   240   89   46  -1.9  -1.0   37.0  98.6    12.2      M    M
 24000  -23.4 -10.1   240   83   43   6.8   3.7   35.9  96.6    11.4      M    M
 23000  -21.3  -6.3   240   76   39   5.6   3.1   34.8  94.7    10.7      M    M
 22000  -20.5  -4.9   240   70   36   2.5   1.4   32.3  90.2     8.8      M    M
 21000  -18.2  -0.8   245   64   33   6.3   3.5   31.6  88.9     8.3      M    M
 20000  -16.3   2.7   245   57   30   6.6   3.6   30.3  86.5     7.3      M    M
 19500  -15.3   4.5   245   54   28   6.6   3.6   29.7  85.5     6.8      M    M
 19000  -14.3   6.3   245   52   27   6.6   3.6   29.1  84.5     6.4      M    M
 18500  -13.7   7.3   245   50   26   2.3   1.2   28.2  82.8     5.6      M    M
 18000  -13.5   7.7   245   48   25   5.6   3.0   26.9  80.4     4.4      M    M
 17500  -12.1  10.2   240   46   24   9.1   5.0   26.7  80.1     4.4      M    M
 17000  -10.9  12.4   240   45   23   5.5   3.0   26.4  79.6     4.1      M    M
 16500   -9.7  14.5   235   42   22   5.2   2.8   25.2  77.4     3.1      M    M
 16000   -8.9  16.0   235   41   21   7.0   3.8   24.6  76.3     2.5      M    M
 15500   -7.9  17.8   230   42   21   7.2   3.9   24.2  75.5     2.1      M    M
 15000   -6.8  19.8   230   42   22   7.2   4.0   23.8  74.8     1.7      M    M
 14500   -5.8  21.6   235   42   22   7.3   4.0   23.3  74.0     1.3      M    M
 14000   -4.7  23.5   235   42   22   7.3   4.0   22.9  73.3     0.9      M    M
 13500   -3.7  25.3   240   40   21   7.2   4.0   22.5  72.5     0.5      M    M
 13000   -2.6  27.3   240   38   20   7.6   4.1   22.1  71.8     0.1      M    M
 12500   -1.3  29.7   240   32   17   9.3   5.1   21.9  71.5    -0.0    595  3.0
 12000    0.1  32.2   245   26   14   7.4   4.1   21.9  71.4    -0.1    540  2.7
 11500    0.4  32.7   250   19   10   1.6   0.9   20.6  69.1    -1.3    516  2.6
 11000    1.4  34.5   265   13    7   8.0   4.4   20.1  68.1    -1.8    472  2.4
 10500    2.5  36.5   260   12    6   7.7   4.2   19.7  67.4    -2.1    425  2.2
 10250    3.0  37.4   260   12    6   4.4   2.4   19.5  67.0    -2.4    403  2.0
 10000    3.2  37.8   260   12    6   4.6   2.5   18.9  66.1    -2.9    389  2.0
  9750    3.7  38.7   260   11    6   8.9   4.9   18.8  65.8    -3.1    364  1.9
  9500    4.4  39.9   260   11    6   8.6   4.7   18.7  65.6    -3.2    338  1.7
  9250    5.0  41.0   260   10    5   8.7   4.8   18.6  65.5    -3.3    311  1.6
  9000    5.7  42.3   260   10    5   8.7   4.8   18.5  65.3    -3.3    284  1.4
  8750    6.3  43.3   260    9    5   8.7   4.8   18.4  65.2    -3.5    258  1.3
  8500    7.0  44.6   260    9    4   8.8   4.8   18.4  65.0    -3.6    231  1.2
  8250    7.6  45.7   260    8    4   8.4   4.6   18.3  64.9    -3.6    204  1.0
  8000    8.2  46.8   260    7    4   6.4   3.5   18.1  64.6    -3.8    180  0.9
  7750    8.6  47.5   260    6    3   5.4   3.0   17.8  64.0    -4.1    160  0.8
  7500    9.0  48.2   265    4    2   5.7   3.1   17.5  63.4    -4.5    140  0.7
  7250    9.4  48.9   270    3    1   5.6   3.1   17.2  62.9    -4.8    120  0.6
  7000    9.8  49.6   295    1    1   5.6   3.1   16.9  62.3    -5.1    100  0.5
  6750   10.3  50.5   340    1    1   5.6   3.1   16.5  61.8    -5.4     80  0.4
  6500   10.7  51.3   005    2    1   5.6   3.1   16.2  61.2    -5.7     60  0.3
  6250   11.1  52.0   015    2    1   5.6   3.1   15.9  60.6    -6.1     40  0.2
  6000   11.5  52.7   025    3    1   5.6   3.0   15.6  60.1    -6.4     20  0.1
  5750   12.0  53.6   035    3    2   5.9   3.2   15.3  59.5    -6.7      M    M
  5500   12.4  54.3   050    3    2   4.7   2.6   15.0  58.9    -7.0      M    M
  5250   12.8  55.0   065    3    2   9.3   5.1   14.6  58.4    -7.4      M    M
  5000   13.1  55.6   075    4    2 -11.6  -6.3   14.2  57.6    -7.8      M    M

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

           10/13/2017 at 0900 MDT          |       10/13/2017 at 1200 MDT
                                           |
K index... -7.2  LI... +6.7                | K index... -16.6  LI... +6.9
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 -64.2 -83.6  250  88 45   1.9   1.1 | -63.8 -82.8  250  88 45   1.7   1.0
 45000 -60.9 -77.6  250 110 56   3.6   2.0 | -60.8 -77.4  250 111 57   3.6   2.0
 40000 -55.2 -67.4  255 122 63   5.1   2.8 | -55.2 -67.4  250 120 62   5.1   2.8
 38000 -51.1 -60.0  255 119 61   7.0   3.8 | -51.0 -59.8  250 117 60   7.1   3.9
 36000 -46.9 -52.4  255 117 60   7.0   3.8 | -46.7 -52.1  250 114 59   7.1   3.9
 34000 -42.8 -45.0  255 111 57   6.6   3.6 | -42.5 -44.5  250 110 57   6.9   3.8
 32000 -38.9 -38.0  255 103 53   6.6   3.6 | -38.4 -37.1  250 104 54   6.9   3.8
 30000 -34.9 -30.8  250  97 50   6.5   3.6 | -34.4 -29.9  250  98 51   6.3   3.5
 29000 -33.0 -27.4  250  94 48   6.5   3.6 | -32.5 -26.5  250  95 49   6.4   3.5
 28000 -31.1 -24.0  250  91 47   6.5   3.6 | -30.1 -22.2  250  91 47   6.4   3.5
 27000 -28.6 -19.5  250  88 45   6.4   3.5 | -28.2 -18.8  250  89 46   6.3   3.4
 26000 -26.7 -16.1  250  85 44   6.4   3.5 | -26.4 -15.5  250  86 44   6.3   3.4
 25000 -24.8 -12.6  250  83 43   6.4   3.5 | -24.5 -12.1  250  84 43   6.3   3.4
 24000 -22.9  -9.2  250  79 41   5.4   2.9 | -22.7  -8.9  250  80 41   5.6   3.0
 23000 -21.3  -6.3  250  74 38   5.4   3.0 | -21.0  -5.8  250  76 39   5.6   3.1
 22000 -19.7  -3.5  255  68 35   5.5   3.0 | -19.3  -2.7  250  71 36   5.6   3.1
 21000 -17.9  -0.2  255  64 33   6.7   3.7 | -17.5   0.5  250  66 34   6.4   3.5
 20000 -15.9   3.4  255  61 31   6.8   3.7 | -15.6   3.9  250  63 32   6.4   3.5
 19500 -14.9   5.2  255  59 30   6.7   3.7 | -14.6   5.7  250  61 31   6.4   3.5
 19000 -13.9   7.0  255  57 29   6.6   3.6 | -13.7   7.3  250  59 30   6.3   3.5
 18500 -13.0   8.6  255  55 28   5.0   2.7 | -12.9   8.8  250  56 29   4.9   2.7
 18000 -12.2  10.0  255  52 27   5.1   2.8 | -12.1  10.2  250  53 27   5.0   2.7
 17500 -11.4  11.5  255  50 26   5.4   3.0 | -11.3  11.7  250  50 26   5.4   3.0
 17000 -10.6  12.9  250  47 24   5.5   3.0 | -10.5  13.1  250  47 24   5.5   3.0
 16500  -9.8  14.4  250  45 23   5.7   3.1 |  -9.7  14.5  250  44 23   5.6   3.1
 16000  -8.9  16.0  250  43 22   6.1   3.4 |  -8.8  16.2  250  42 22   5.6   3.1
 15500  -8.0  17.6  250  41 21   6.1   3.4 |  -8.0  17.6  250  39 20   5.6   3.0
 15000  -7.1  19.2  250  39 20   6.4   3.5 |  -7.1  19.2  250  37 19   6.4   3.5
 14500  -6.2  20.8  245  36 19   6.4   3.5 |  -6.2  20.8  250  35 18   6.3   3.5
 14000  -5.2  22.6  245  34 18   6.3   3.5 |  -5.2  22.6  245  33 17   6.5   3.6
 13500  -4.3  24.3  245  32 17   6.3   3.5 |  -3.8  25.2  245  31 16   6.7   3.7
 13000  -2.9  26.8  245  29 15   7.1   3.9 |  -2.8  27.0  245  30 15   7.4   4.1
 12500  -1.9  28.6  240  26 14   7.1   3.9 |  -1.7  28.9  240  28 15   7.4   4.1
 12000  -1.0  30.2  240  23 12   6.0   3.3 |  -0.6  30.9  240  27 14   8.0   4.4
 11500  -0.1  31.8  240  19 10   6.0   3.3 |   0.5  32.9  240  25 13   8.0   4.4
 11000   0.9  33.6  240  16  8   7.7   4.2 |   1.6  34.9  240  22 12   6.8   3.7
 10500   2.1  35.8  235  14  7   7.1   3.9 |   2.7  36.9  235  19 10   6.2   3.4
 10250   2.5  36.5  235  12  6   5.3   2.9 |   3.0  37.4  235  18  9   4.5   2.5
 10000   2.9  37.2  230  12  6   6.9   3.8 |   3.4  38.1  235  16  8   6.4   3.5
  9750   3.6  38.5  230  11  6   8.9   4.9 |   4.0  39.2  235  15  8   8.2   4.5
  9500   4.2  39.6  225  10  5   7.8   4.3 |   4.5  40.1  235  14  7   7.4   4.1
  9250   4.7  40.5  220   9  5   5.4   2.9 |   5.1  41.2  230  12  6   6.0   3.3
  9000   5.1  41.2  215   9  5   5.1   2.8 |   5.5  41.9  230  11  6   6.4   3.5
  8750   5.5  41.9  205   8  4   6.4   3.5 |   6.0  42.8  225  10  5   7.7   4.2
  8500   6.0  42.8  200   8  4   5.8   3.2 |   6.6  43.9  225   9  5   6.8   3.7
  8250   6.4  43.5  195   7  4   5.5   3.0 |   7.0  44.6  220   8  4   5.7   3.1
  8000   6.8  44.2  190   7  4   5.3   2.9 |   7.4  45.3  215   7  4   6.1   3.3
  7750   7.2  45.0  185   6  3   5.1   2.8 |   7.9  46.2  210   7  3   6.6   3.6
  7500   7.6  45.7  180   6  3   5.3   2.9 |   8.4  47.1  200   6  3   7.8   4.3
  7250   8.0  46.4  175   6  3   5.3   2.9 |   9.1  48.4  200   6  3   9.0   4.9
  7000   8.4  47.1  170   6  3   5.8   3.2 |   9.7  49.5  200   6  3   8.7   4.8
  6750   8.8  47.8  170   6  3   3.2   1.7 |  10.4  50.7  200   5  3   9.8   5.4
  6500   8.8  47.8  165   6  3  -1.1  -0.6 |  11.2  52.2  200   5  3  11.1   6.1
  6250   8.6  47.5  160   6  3  -3.1  -1.7 |  12.0  53.6  200   5  3  11.6   6.4
  6000   8.5  47.3  155   7  3   1.1   0.6 |  12.9  55.2  205   5  3  10.6   5.8
  5750   8.7  47.7  145   6  3   0.9   0.5 |  13.7  56.7  205   5  2  11.4   6.3
  5500   8.4  47.1  135   6  3  -4.2  -2.3 |  14.6  58.3  205   5  2  13.3   7.3
  5250   8.2  46.8  125   5  2  -0.0  -0.0 |  15.6  60.1  210   5  2  11.8   6.5
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           10/13/2017 at 1500 MDT          |       10/13/2017 at 1800 MDT
                                           |
K index... -5.6  LI... +5.7                | K index... -4.3  LI... +4.6
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 -63.7 -82.7  255  88 45   1.6   0.9 | -63.8 -82.8  255  89 46   1.6   0.9
 45000 -60.9 -77.6  250 112 58   3.7   2.0 | -61.0 -77.8  255 114 58   3.9   2.1
 40000 -55.1 -67.2  245 120 62   5.0   2.7 | -54.9 -66.8  250 122 63   4.9   2.7
 38000 -50.9 -59.6  250 117 60   7.0   3.9 | -51.0 -59.8  250 118 61   6.7   3.7
 36000 -46.7 -52.1  250 114 58   7.0   3.9 | -46.9 -52.4  250 115 59   6.7   3.7
 34000 -42.5 -44.5  250 110 56   7.0   3.9 | -42.8 -45.0  250 110 57   7.0   3.8
 32000 -38.3 -36.9  245 105 54   7.0   3.9 | -38.7 -37.7  245 106 55   7.0   3.8
 30000 -34.3 -29.7  245 100 51   6.4   3.5 | -34.7 -30.5  245 101 52   6.3   3.5
 29000 -32.4 -26.3  250  97 50   6.4   3.5 | -32.8 -27.0  250  99 51   6.3   3.5
 28000 -30.0 -22.0  250  94 48   6.4   3.5 | -30.9 -23.6  250  97 50   6.3   3.5
 27000 -28.1 -18.6  250  91 47   6.1   3.4 | -28.6 -19.5  250  93 48   6.1   3.3
 26000 -26.3 -15.3  250  88 45   6.1   3.4 | -26.8 -16.2  250  89 46   6.1   3.3
 25000 -24.4 -11.9  250  85 44   6.2   3.4 | -24.9 -12.8  250  85 44   6.1   3.3
 24000 -22.6  -8.7  250  82 42   5.7   3.1 | -23.1  -9.6  250  81 42   5.9   3.2
 23000 -20.9  -5.6  250  78 40   5.8   3.2 | -21.4  -6.5  250  78 40   5.9   3.2
 22000 -19.2  -2.6  250  74 38   5.8   3.2 | -19.6  -3.3  250  74 38   5.9   3.2
 21000 -17.3   0.9  250  71 36   6.4   3.5 | -17.9  -0.2  250  70 36   5.9   3.2
 20000 -15.4   4.3  250  67 35   6.4   3.5 | -16.1   3.0  255  66 34   5.9   3.2
 19500 -14.5   5.9  250  66 34   6.4   3.5 | -15.2   4.6  255  63 33   5.9   3.2
 19000 -13.5   7.7  250  64 33   6.4   3.5 | -14.3   6.3  255  61 31   5.9   3.2
 18500 -12.7   9.1  250  62 32   5.4   3.0 | -13.5   7.7  255  58 30   5.6   3.1
 18000 -11.8  10.8  250  59 30   5.5   3.0 | -12.6   9.3  255  55 28   5.6   3.1
 17500 -11.0  12.2  250  56 29   5.1   2.8 | -11.8  10.8  255  52 27   6.0   3.3
 17000 -10.3  13.5  250  53 27   4.9   2.7 | -10.9  12.4  250  49 25   6.2   3.4
 16500  -9.6  14.7  250  50 26   4.8   2.6 |  -9.9  14.2  250  47 24   6.2   3.4
 16000  -8.9  16.0  245  47 24   4.7   2.6 |  -9.0  15.8  250  44 23   6.4   3.5
 15500  -8.2  17.2  245  44 23   4.5   2.5 |  -8.0  17.6  245  42 22   6.3   3.5
 15000  -7.4  18.7  245  41 21   6.8   3.7 |  -7.0  19.4  240  40 21   7.6   4.1
 14500  -6.4  20.5  240  38 20   6.7   3.7 |  -5.9  21.4  240  38 20   7.5   4.1
 14000  -5.4  22.3  235  35 18   7.5   4.1 |  -4.8  23.4  235  36 18   8.5   4.7
 13500  -3.7  25.3  235  31 16   7.8   4.3 |  -3.5  25.7  235  34 17   8.8   4.8
 13000  -2.5  27.5  230  29 15   9.1   5.0 |  -1.6  29.1  230  30 16   9.3   5.1
 12500  -1.2  29.8  230  27 14   9.0   4.9 |  -0.2  31.6  230  28 15   9.3   5.1
 12000   0.1  32.2  230  25 13   8.5   4.7 |   1.1  34.0  230  27 14   8.9   4.9
 11500   1.4  34.5  230  23 12   8.7   4.8 |   2.5  36.5  230  25 13   9.1   5.0
 11000   2.6  36.7  230  21 11   7.6   4.1 |   3.7  38.7  230  23 12   7.7   4.2
 10500   3.8  38.8  230  19 10   7.3   4.0 |   4.9  40.8  230  21 11   8.3   4.6
 10250   4.2  39.6  230  18  9   5.3   2.9 |   5.4  41.7  230  21 11   5.5   3.0
 10000   4.6  40.3  230  17  9   6.8   3.7 |   5.8  42.4  230  19 10   5.9   3.2
  9750   5.2  41.4  230  16  8   8.8   4.8 |   6.4  43.5  235  18  9   8.9   4.9
  9500   5.9  42.6  230  14  7   8.2   4.5 |   7.0  44.6  235  17  9   8.2   4.5
  9250   6.4  43.5  235  13  7   6.7   3.7 |   7.6  45.7  235  16  8   6.8   3.7
  9000   6.9  44.4  235  11  6   5.9   3.3 |   8.0  46.4  235  15  8   5.9   3.2
  8750   7.3  45.1  240   9  5   6.5   3.6 |   8.5  47.3  235  14  7   6.6   3.6
  8500   7.8  46.0  245   8  4   6.7   3.7 |   9.0  48.2  240  13  7   6.4   3.5
  8250   8.3  46.9  255   7  3   7.3   4.0 |   9.4  48.9  240  11  6   6.4   3.5
  8000   8.9  48.0  260   6  3   8.6   4.7 |   9.9  49.8  245  10  5   6.0   3.3
  7750   9.6  49.3  265   6  3   9.5   5.2 |  10.3  50.5  250   8  4   5.4   2.9
  7500  10.3  50.5  265   6  3   9.8   5.4 |  10.7  51.3  255   6  3   6.2   3.4
  7250  11.1  52.0  265   6  3  10.5   5.7 |  11.2  52.2  265   5  3   7.1   3.9
  7000  11.9  53.4  270   6  3  10.2   5.6 |  11.8  53.2  275   5  3   7.1   3.9
  6750  12.6  54.7  270   6  3  10.1   5.5 |  12.3  54.1  285   5  2   7.3   4.0
  6500  13.4  56.1  270   6  3  10.6   5.8 |  12.9  55.2  290   5  2   8.8   4.8
  6250  14.2  57.6  270   6  3  11.3   6.2 |  13.6  56.5  290   5  2   9.7   5.3
  6000  15.0  59.0  270   6  3   9.8   5.4 |  14.3  57.7  295   5  2   9.8   5.4
  5750  15.7  60.3  275   6  3  10.6   5.8 |  15.0  59.0  300   5  2   6.6   3.6
  5500  16.6  61.9  275   6  3  13.3   7.3 |  15.2  59.4  300   4  2   2.3   1.2
  5250  17.6  63.7  270   6  3  12.1   6.6 |  15.4  59.7  300   4  2   3.7   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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