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
0648 MDT Wednesday, October 15, 2014

This forecast is for Wednesday, October 15, 2014:

If the trigger temperature of 72.4 F/22.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 122 ft/min (0.6 m/s)
   Maximum height of thermals.................. 9526 ft MSL (4687 ft AGL)

Forecast maximum temperature................... 74.0 F/23.8 C
Time of trigger temperature.................... 1400 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7007 ft MSL (2167 ft AGL)
Thermal soaring outlook for Thursday 10/16..... Fair

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

Remarks...

Sunrise/Sunset.................... 07:23:53 / 18:36:50 MDT
Total possible sunshine........... 11 hr 12 min 58 sec (672 min 58 sec)
Altitude of sun at 12:59:55 MDT... 42.21 degrees

Upper air data from rawinsonde observation taken on 10/15/2014 at 0600 MDT

Freezing level.................. 15759 ft MSL (10920 ft AGL)
Convective condensation level... 20311 ft MSL (15472 ft AGL)
Lifted condensation level....... 15812 ft MSL (10973 ft AGL)
Lifted index.................... +7.5
K index......................... -19.0

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  -69.2 -92.6   235   51   26   2.7   1.5   80.7 177.3    33.1      M    M
 45000  -62.0 -79.6   235   52   27   6.5   3.6   68.2 154.8    27.8      M    M
 40000  -58.5 -73.3   250   66   34   4.5   2.4   50.9 123.6    18.2      M    M
 38000  -53.1 -63.6   250   55   29   9.0   4.9   49.8 121.7    18.0      M    M
 36000  -47.7 -53.9   250   45   23   8.9   4.9   49.4 120.9    18.2      M    M
 34000  -41.6 -42.9   240   38   20   8.8   4.8   48.8 119.9    18.3      M    M
 32000  -37.1 -34.8   230   40   21   5.3   2.9   47.0 116.6    17.4      M    M
 30000  -33.5 -28.3   240   49   25   8.5   4.7   44.0 111.2    15.6      M    M
 29000  -30.9 -23.6   240   48   25   8.6   4.7   43.4 110.1    15.3      M    M
 28000  -28.3 -18.9   240   47   24   8.6   4.7   42.9 109.2    15.1      M    M
 27000  -25.8 -14.4   235   47   24   8.6   4.7   42.5 108.5    15.0      M    M
 26000  -23.7 -10.7   235   46   24   5.9   3.2   41.5 106.7    14.4      M    M
 25000  -21.6  -6.9   235   45   23   9.0   4.9   40.5 105.0    13.8      M    M
 24000  -19.1  -2.4   235   44   23   8.0   4.4   40.0 104.0    13.5      M    M
 23000  -17.2   1.0   230   43   22   5.5   3.0   38.7 101.7    12.6      M    M
 22000  -15.6   3.9   230   43   22   5.5   3.0   37.2  98.9    11.4      M    M
 21000  -13.6   7.5   225   42   22   9.2   5.0   36.1  97.0    10.7      M    M
 20000  -10.9  12.4   225   41   21   9.0   4.9   35.9  96.6    10.6      M    M
 19500   -9.5  14.9   225   40   21   9.0   4.9   35.7  96.3    10.5      M    M
 19000   -8.2  17.2   230   40   21   8.7   4.7   35.6  96.0    10.4      M    M
 18500   -6.3  20.7   230   40   21   8.5   4.6   35.2  95.3    10.2      M    M
 18000   -5.0  23.0   225   40   21   8.5   4.6   34.9  94.9    10.0      M    M
 17500   -3.7  25.3   225   40   21   8.4   4.6   34.7  94.5     9.9      M    M
 17000   -2.5  27.5   225   40   21   8.3   4.5   34.5  94.2     9.8      M    M
 16500   -1.4  29.5   220   40   21   6.8   3.8   34.2  93.5     9.5      M    M
 16000   -0.3  31.5   220   40   21   6.9   3.8   33.7  92.6     9.1      M    M
 15500    0.7  33.3   220   40   21   6.9   3.8   33.2  91.8     8.8      M    M
 15000    1.7  35.1   220   40   21   6.8   3.7   32.7  90.9     8.4      M    M
 14500    2.8  37.0   225   39   20   5.4   3.0   32.3  90.1     8.0      M    M
 14000    3.3  37.9   225   38   19   3.8   2.1   31.3  88.3     7.1      M    M
 13500    3.9  39.0   220   35   18   3.4   1.9   30.3  86.5     6.2      M    M
 13000    4.6  40.3   220   33   17   7.0   3.9   29.5  85.0     5.5      M    M
 12500    5.7  42.3   215   30   16   7.2   4.0   29.1  84.3     5.1      M    M
 12000    6.8  44.2   210   28   14   7.2   4.0   28.7  83.6     4.8      M    M
 11500    7.8  46.0   210   26   13   7.0   3.9   28.2  82.8     4.4      M    M
 11000    8.9  48.0   215   24   12   4.3   2.4   27.8  82.1     4.1      M    M
 10500    9.0  48.2   215   22   11   0.7   0.4   26.4  79.6     2.7      M    M
 10250    9.0  48.2   215   21   11   0.9   0.5   25.7  78.3     2.0      M    M
 10000    9.1  48.4   215   18    9   1.3   0.7   25.0  77.0     1.3      M    M
  9750    9.1  48.4   215   16    8   0.8   0.4   24.3  75.8     0.6      M    M
  9500    9.2  48.6   215   14    7   2.7   1.5   23.7  74.6    -0.0    321  1.6
  9250    9.5  49.1   215   11    6   6.3   3.4   23.3  73.9    -0.4    304  1.5
  9000   10.0  50.0   215    9    5   7.0   3.9   23.1  73.5    -0.7    282  1.4
  8750   10.5  50.9   200   10    5   6.9   3.8   22.8  73.1    -0.9    260  1.3
  8500   11.0  51.8   185   13    7   6.9   3.8   22.6  72.7    -1.1    237  1.2
  8250   11.5  52.7   175   16    8   6.9   3.8   22.4  72.3    -1.4    215  1.1
  8000   12.0  53.6   170   19   10   6.9   3.8   22.2  71.9    -1.6    193  1.0
  7750   12.5  54.5   165   20   10   7.2   3.9   22.0  71.5    -1.9    171  0.9
  7500   13.0  55.4   165   22   11   6.2   3.4   21.7  71.1    -2.1    149  0.8
  7250   13.5  56.3   160   23   12  10.0   5.5   21.5  70.7    -2.4    126  0.6
  7000   13.9  57.0   160   25   13  -4.0  -2.2   21.3  70.4    -2.6    104  0.5
  6750   12.6  54.7   160   26   13 -25.4 -14.0   19.2  66.6    -4.7    137  0.7
  6500   11.1  52.0   160   27   14  -7.8  -4.3   16.9  62.5    -7.0    176  0.9
  6250   11.2  52.2   165   28   15   1.9   1.0   16.3  61.4    -7.6    166  0.8
  6000   10.9  51.6   165   30   15  -5.6  -3.1   15.3  59.5    -8.7    167  0.9
  5750   10.6  51.1   165   25   13  -3.5  -1.9   14.2  57.6    -9.7    169  0.9
  5500   10.2  50.4   160   19   10  -4.2  -2.3   13.2  55.7   -10.8    171  0.9
  5250    9.9  49.8   150   12    6  -3.6  -2.0   12.2  53.9   -11.9    173  0.9
  5000    9.6  49.3   130    7    3  -5.2  -2.9   11.1  52.0   -12.9    175  0.9

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

           10/15/2014 at 0900 MDT          |       10/15/2014 at 1200 MDT
                                           |
K index... -6.1  LI... +6.2                | K index... +1.7  LI... +5.4
CAPE... 0.0  CIN... -1.0                   | CAPE... 0.0  CIN... -0.0
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -68.9 -92.0  240  47 24   2.9   1.6 | -68.7 -91.7  240  53 27   3.1   1.7
 45000 -64.1 -83.4  245  54 28   4.6   2.5 | -63.8 -82.8  235  61 31   4.3   2.3
 40000 -56.6 -69.9  250  70 36   8.0   4.4 | -56.9 -70.4  240  85 44   7.6   4.2
 38000 -52.0 -61.6  250  66 34   7.6   4.2 | -52.5 -62.5  240  75 38   7.3   4.0
 36000 -47.5 -53.5  250  62 32   7.6   4.2 | -48.1 -54.6  240  65 33   7.4   4.0
 34000 -42.7 -44.9  245  57 30   8.0   4.4 | -43.3 -45.9  235  61 31   8.2   4.5
 32000 -37.9 -36.2  235  54 28   8.0   4.4 | -38.4 -37.1  235  60 31   8.2   4.5
 30000 -33.5 -28.3  235  51 27   6.9   3.8 | -34.0 -29.2  230  56 29   6.8   3.7
 29000 -30.9 -23.6  235  50 26   6.9   3.8 | -31.5 -24.7  230  52 27   6.8   3.7
 28000 -28.9 -20.0  240  49 25   7.5   4.1 | -29.5 -21.1  225  49 25   7.4   4.1
 27000 -26.3 -15.3  240  48 25   8.5   4.6 | -26.9 -16.4  230  49 25   8.6   4.7
 26000 -23.8 -10.8  240  46 24   8.5   4.6 | -24.3 -11.7  230  49 25   8.6   4.7
 25000 -21.3  -6.3  235  45 23   8.7   4.8 | -21.7  -7.1  230  49 25   8.8   4.8
 24000 -19.2  -2.6  235  44 23   6.3   3.5 | -19.5  -3.1  235  48 25   6.9   3.8
 23000 -17.3   0.9  235  45 23   6.3   3.5 | -17.4   0.7  235  47 24   6.9   3.8
 22000 -15.4   4.3  235  45 23   6.3   3.4 | -15.3   4.5  235  46 24   6.8   3.8
 21000 -13.3   8.1  235  42 22   7.4   4.1 | -13.1   8.4  235  45 23   7.7   4.2
 20000 -11.1  12.0  230  38 20   7.4   4.1 | -10.8  12.6  230  43 22   7.7   4.2
 19500 -10.0  14.0  230  36 19   7.4   4.0 |  -9.7  14.5  230  42 22   7.7   4.2
 19000  -8.8  16.2  230  35 18   8.4   4.6 |  -8.5  16.7  225  42 21   8.2   4.5
 18500  -7.5  18.5  230  33 17   8.7   4.8 |  -7.3  18.9  225  41 21   8.3   4.6
 18000  -6.2  20.8  230  31 16   8.7   4.7 |  -6.0  21.2  230  41 21   8.3   4.5
 17500  -5.0  23.0  230  32 17   7.5   4.1 |  -4.9  23.2  230  42 21   6.8   3.8
 17000  -3.9  25.0  230  35 18   7.6   4.2 |  -3.9  25.0  230  43 22   7.0   3.8
 16500  -2.8  27.0  230  38 19   7.3   4.0 |  -2.9  26.8  230  45 23   6.7   3.7
 16000  -1.7  28.9  230  38 20   7.2   4.0 |  -1.9  28.6  230  43 22   6.6   3.6
 15500  -0.6  30.9  230  39 20   7.0   3.9 |  -1.0  30.2  230  41 21   6.4   3.5
 15000   0.4  32.7  230  38 20   6.6   3.6 |  -0.0  32.0  230  40 21   6.1   3.4
 14500   1.3  34.3  230  37 19   6.7   3.7 |   0.9  33.6  230  39 20   6.1   3.4
 14000   2.7  36.9  225  36 18   6.0   3.3 |   2.1  35.8  230  37 19   5.6   3.1
 13500   3.6  38.5  225  35 18   5.8   3.2 |   3.0  37.4  230  35 18   5.5   3.0
 13000   4.4  39.9  225  34 17   5.5   3.0 |   3.7  38.7  230  33 17   5.2   2.8
 12500   5.2  41.4  225  33 17   5.5   3.0 |   4.4  39.9  230  31 16   5.4   3.0
 12000   6.0  42.8  225  31 16   5.7   3.1 |   5.2  41.4  230  29 15   6.0   3.3
 11500   6.8  44.2  225  30 15   5.8   3.2 |   6.0  42.8  230  27 14   6.2   3.4
 11000   7.7  45.9  220  29 15   6.1   3.4 |   7.0  44.6  230  25 13   6.6   3.6
 10500   8.6  47.5  220  28 14   3.4   1.9 |   8.0  46.4  230  24 12   4.0   2.2
 10250   8.7  47.7  220  27 14   4.2   2.3 |   8.2  46.8  230  23 12   4.5   2.4
 10000   9.3  48.7  220  26 14   8.8   4.8 |   8.7  47.7  225  23 12   8.3   4.5
  9750   9.9  49.8  220  26 13   8.1   4.5 |   9.3  48.7  225  23 12   7.5   4.1
  9500  10.5  50.9  220  25 13   7.3   4.0 |   9.8  49.6  225  22 11   6.9   3.8
  9250  10.9  51.6  220  25 13   5.1   2.8 |  10.3  50.5  225  22 11   5.3   2.9
  9000  11.3  52.3  215  24 12   5.7   3.1 |  10.7  51.3  220  22 11   5.9   3.2
  8750  11.8  53.2  215  24 12   6.9   3.8 |  11.2  52.2  220  21 11   6.8   3.7
  8500  12.3  54.1  215  23 12   5.8   3.2 |  11.7  53.1  215  21 11   5.9   3.2
  8250  12.6  54.7  210  22 11   5.0   2.7 |  12.1  53.8  215  19 10   5.2   2.9
  8000  13.0  55.4  210  21 11   4.0   2.2 |  12.4  54.3  210  17  9   4.6   2.5
  7750  13.2  55.8  205  20 10   3.2   1.7 |  12.7  54.9  210  14  7   3.8   2.1
  7500  13.5  56.3  200  19 10   1.9   1.0 |  13.1  55.6  205  12  6   5.7   3.1
  7250  13.5  56.3  195  18  9   0.6   0.3 |  13.6  56.5  200  11  5   7.0   3.9
  7000  13.6  56.5  190  17  9   1.3   0.7 |  14.1  57.4  200   9  5   6.9   3.8
  6750  13.6  56.5  180  16  8  -1.5  -0.8 |  14.6  58.3  200   8  4   8.6   4.7
  6500  13.3  55.9  175  15  7  -6.1  -3.4 |  15.3  59.5  200   8  4  10.1   5.5
  6250  12.7  54.9  170  13  7  -9.2  -5.0 |  16.1  61.0  200   7  4  11.0   6.0
  6000  12.1  53.8  160  11  6  -2.8  -1.5 |  16.9  62.4  205   7  4   9.3   5.1
  5750  12.0  53.6  135   8  4  -5.3  -2.9 |  17.6  63.7  205   6  3   9.7   5.3
  5500  11.1  52.0  130   7  4 -15.0  -8.2 |  18.4  65.1  205   6  3  11.9   6.5
  5250  10.1  50.2  115   6  3  -7.2  -3.9 |  19.2  66.6  205   6  3  10.1   5.6
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           10/15/2014 at 1500 MDT          |       10/15/2014 at 1800 MDT
                                           |
K index... +6.3  LI... +4.7                | K index... +5.5  LI... +3.6
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... M
                                           |
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 -67.5 -89.5  250  59 30   2.6   1.4 | -68.4 -91.1  250  60 31   3.1   1.7
 45000 -63.4 -82.1  245  74 38   3.7   2.0 | -63.5 -82.3  250  75 39   4.5   2.5
 40000 -57.4 -71.3  240  87 45   7.6   4.2 | -56.2 -69.2  250  87 45   6.5   3.6
 38000 -52.7 -62.9  240  80 41   7.8   4.3 | -52.2 -62.0  245  84 43   6.7   3.7
 36000 -48.0 -54.4  235  74 38   7.9   4.3 | -48.2 -54.8  245  82 42   6.7   3.7
 34000 -43.1 -45.6  235  69 35   8.3   4.6 | -43.5 -46.3  245  76 39   8.4   4.6
 32000 -38.1 -36.6  240  64 33   8.4   4.6 | -38.5 -37.3  245  69 35   8.4   4.6
 30000 -34.0 -29.2  235  60 31   5.9   3.2 | -33.9 -29.0  245  64 33   7.3   4.0
 29000 -31.8 -25.2  235  58 30   5.9   3.2 | -31.7 -25.1  250  63 32   7.3   4.0
 28000 -30.0 -22.0  230  57 29   6.4   3.5 | -28.9 -20.0  250  61 32   7.3   4.0
 27000 -27.6 -17.7  230  55 28   8.2   4.5 | -26.8 -16.2  245  55 29   7.1   3.9
 26000 -25.2 -13.4  235  53 27   8.2   4.5 | -24.7 -12.5  240  49 25   7.1   3.9
 25000 -22.7  -8.9  240  51 26   8.3   4.5 | -22.5  -8.5  235  43 22   7.1   3.9
 24000 -20.3  -4.5  240  50 26   7.7   4.2 | -20.4  -4.7  235  43 22   7.0   3.8
 23000 -18.0  -0.4  240  50 26   7.7   4.2 | -18.3  -0.9  240  47 24   7.0   3.8
 22000 -15.7   3.7  240  50 26   7.7   4.2 | -16.2   2.8  245  52 27   6.9   3.8
 21000 -13.4   7.9  240  49 25   7.8   4.3 | -14.1   6.6  250  52 27   7.4   4.1
 20000 -11.1  12.0  240  49 25   7.8   4.3 | -11.9  10.6  250  50 26   7.4   4.1
 19500  -9.9  14.2  240  48 25   7.8   4.3 | -10.8  12.6  250  49 25   7.5   4.1
 19000  -8.8  16.2  240  48 25   7.2   4.0 |  -9.7  14.5  250  48 25   7.3   4.0
 18500  -7.7  18.1  240  48 25   7.0   3.8 |  -8.6  16.5  250  47 24   7.2   4.0
 18000  -6.7  19.9  240  48 25   7.0   3.9 |  -7.5  18.5  250  46 24   7.3   4.0
 17500  -5.7  21.7  240  48 25   7.1   3.9 |  -6.4  20.5  250  45 23   7.1   3.9
 17000  -4.6  23.7  240  47 24   7.1   3.9 |  -5.4  22.3  250  44 23   7.1   3.9
 16500  -3.6  25.5  240  47 24   6.7   3.7 |  -4.4  24.1  250  44 22   6.8   3.8
 16000  -2.6  27.3  240  46 24   6.5   3.6 |  -3.4  25.9  250  43 22   6.7   3.7
 15500  -1.7  28.9  240  45 23   6.5   3.6 |  -2.4  27.7  250  42 22   6.8   3.7
 15000  -0.7  30.7  240  44 23   6.3   3.5 |  -1.3  29.7  250  41 21   7.0   3.8
 14500   0.2  32.4  240  43 22   6.4   3.5 |  -0.3  31.5  250  40 21   7.0   3.8
 14000   1.5  34.7  240  41 21   5.7   3.1 |   0.7  33.3  250  40 20   6.6   3.6
 13500   2.3  36.1  235  40 20   5.7   3.1 |   2.2  36.0  245  39 20   6.8   3.7
 13000   3.1  37.6  235  38 19   5.7   3.1 |   3.2  37.8  245  37 19   7.1   3.9
 12500   3.9  39.0  235  36 18   5.9   3.2 |   4.3  39.7  245  35 18   7.2   3.9
 12000   4.9  40.8  235  33 17   7.0   3.8 |   5.3  41.5  240  31 16   7.8   4.3
 11500   5.8  42.4  230  29 15   7.0   3.9 |   6.4  43.5  235  28 14   7.9   4.3
 11000   7.0  44.6  230  26 14   8.0   4.4 |   7.4  45.3  230  24 13   7.6   4.2
 10500   8.1  46.6  225  23 12   4.5   2.4 |   8.5  47.3  225  22 11  10.4   5.7
 10250   8.3  46.9  220  22 11   5.3   2.9 |   9.4  48.9  220  21 11  11.2   6.1
 10000   9.0  48.2  220  21 11  10.6   5.8 |  10.0  50.0  220  20 10   8.0   4.4
  9750   9.7  49.5  220  19 10   9.3   5.1 |  10.7  51.3  215  19 10   8.9   4.9
  9500  10.4  50.7  215  18  9   9.1   5.0 |  11.3  52.3  215  18  9   8.3   4.6
  9250  11.0  51.8  215  17  9   7.9   4.3 |  11.9  53.4  210  17  9   7.5   4.1
  9000  11.6  52.9  215  16  8   8.0   4.4 |  12.4  54.3  210  17  9   7.7   4.2
  8750  12.2  54.0  215  15  8   8.5   4.7 |  13.0  55.4  210  16  8   8.2   4.5
  8500  12.8  55.0  215  14  7   8.0   4.4 |  13.6  56.5  210  15  8   7.8   4.3
  8250  13.4  56.1  215  12  6   7.2   4.0 |  14.2  57.6  205  15  7   7.3   4.0
  8000  13.9  57.0  215  11  5   7.3   4.0 |  14.7  58.5  205  14  7   6.9   3.8
  7750  14.5  58.1  220   9  5   7.1   3.9 |  15.2  59.4  205  12  6   6.7   3.7
  7500  15.0  59.0  225   8  4   8.3   4.6 |  15.7  60.3  205  11  6   6.8   3.8
  7250  15.7  60.3  225   8  4   9.7   5.3 |  16.2  61.2  205  10  5   6.9   3.8
  7000  16.4  61.5  230   7  4   9.1   5.0 |  16.7  62.1  210   8  4   7.0   3.9
  6750  17.1  62.8  235   7  4   9.2   5.1 |  17.2  63.0  210   7  4   7.3   4.0
  6500  17.8  64.0  235   7  4  10.2   5.6 |  17.8  64.0  215   6  3   8.0   4.4
  6250  18.6  65.5  235   7  3  10.9   6.0 |  18.4  65.1  220   5  3   8.3   4.6
  6000  19.4  66.9  240   7  3  10.0   5.5 |  19.0  66.2  225   4  2   8.5   4.7
  5750  20.1  68.2  240   6  3  10.2   5.6 |  19.6  67.3  240   3  2   5.6   3.1
  5500  20.9  69.6  240   6  3  11.4   6.3 |  19.8  67.6  245   3  1   1.6   0.9
  5250  21.7  71.1  240   7  3  10.9   6.0 |  19.9  67.8  240   3  1   2.7   1.5
  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 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  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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