Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 291241
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0640 MDT Monday, September 29, 2014

This forecast is for Monday, September 29, 2014:

If the trigger temperature of 65.2 F/18.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7504 ft MSL (2665 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... 1415 MDT
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................. 6995 ft MSL (2156 ft AGL)
Thermal soaring outlook for Tuesday 09/30...... Good

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

Remarks...

Sunrise/Sunset.................... 07:08:19 / 19:01:23 MDT
Total possible sunshine........... 11 hr 53 min 4 sec (713 min 4 sec)
Altitude of sun at 13:04:22 MDT... 48.29 degrees

Upper air data from rawinsonde observation taken on 09/29/2014 at 0600 MDT

Freezing level.................. 11561 ft MSL (6722 ft AGL)
Convective condensation level... 10809 ft MSL (5970 ft AGL)
Lifted condensation level....... 10097 ft MSL (5258 ft AGL)
Lifted index.................... -0.4
K index......................... +6.6

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  -60.3 -76.5   220   31   16   4.2   2.3   98.1 208.7    46.1      M    M
 45000  -56.6 -69.9   220   65   34  -0.4  -0.2   78.5 173.3    37.4      M    M
 40000  -51.6 -60.9   225   65   33   5.1   2.8   63.3 145.9    30.0      M    M
 38000  -49.9 -57.8   225   88   46 -10.3  -5.6   57.2 134.9    26.6      M    M
 36000  -48.5 -55.3   220   89   46   4.7   2.6   50.5 122.9    22.7      M    M
 34000  -46.2 -51.2   215   90   46   7.6   4.2   45.5 113.9    19.8      M    M
 32000  -41.6 -42.9   215   92   47   9.1   5.0   42.9 109.1    18.4      M    M
 30000  -37.0 -34.6   220   90   46   5.9   3.3   41.3 106.3    17.6      M    M
 29000  -35.4 -31.7   220   85   44   1.0   0.6   39.5 103.2    16.5      M    M
 28000  -33.4 -28.1   215   81   42   7.4   4.1   38.3 101.0    15.8      M    M
 27000  -31.2 -24.2   215   77   39   6.5   3.6   37.4  99.4    15.3      M    M
 26000  -30.4 -22.7   215   68   35   1.9   1.0   34.7  94.5    13.3      M    M
 25000  -28.2 -18.8   215   59   30   9.3   5.1   33.9  93.0    12.8      M    M
 24000  -25.5 -13.9   215   58   30   6.3   3.4   33.6  92.5    12.7      M    M
 23000  -24.1 -11.4   215   56   29   1.4   0.8   31.7  89.0    11.3      M    M
 22000  -22.0  -7.6   210   54   28   7.6   4.2   30.6  87.1    10.5      M    M
 21000  -19.4  -2.9   210   51   26   9.2   5.0   30.2  86.4    10.4      M    M
 20000  -17.3   0.9   205   49   25   6.0   3.3   29.3  84.7     9.7      M    M
 19500  -16.4   2.5   205   46   24   6.1   3.4   28.6  83.4     9.1      M    M
 19000  -15.5   4.1   205   43   22   5.4   3.0   27.9  82.1     8.6      M    M
 18500  -14.8   5.4   205   41   21   3.9   2.1   27.0  80.5     7.9      M    M
 18000  -13.9   7.0   205   41   21   8.7   4.8   26.4  79.4     7.4      M    M
 17500  -12.5   9.5   205   40   21   9.3   5.1   26.3  79.3     7.4      M    M
 17000  -10.4  13.3   205   40   20   6.7   3.7   26.1  79.0     7.3      M    M
 16500   -9.7  14.5   205   39   20   5.1   2.8   25.3  77.6     6.6      M    M
 16000   -9.0  15.8   205   39   20   5.0   2.7   24.5  76.1     5.9      M    M
 15500   -8.3  17.1   205   37   19   5.0   2.7   23.7  74.6     5.2      M    M
 15000   -7.5  18.5   210   36   19   5.1   2.8   22.9  73.2     4.5      M    M
 14500   -6.8  19.8   210   35   18   6.3   3.5   22.1  71.8     3.8      M    M
 14000   -5.6  21.9   210   34   17   8.8   4.8   21.9  71.4     3.6      M    M
 13500   -4.3  24.3   205   33   17   8.7   4.8   21.7  71.1     3.5      M    M
 13000   -3.0  26.6   200   32   17   8.7   4.8   21.5  70.8     3.3      M    M
 12500   -1.7  28.9   200   31   16   6.8   3.7   21.4  70.5     3.2      M    M
 12000   -1.1  30.0   195   31   16   7.1   3.9   20.7  69.3     2.4      M    M
 11500    0.3  32.5   195   28   14   9.6   5.3   20.7  69.2     2.2      M    M
 11000    1.4  34.5   195   24   13   7.1   3.9   20.2  68.4     1.9      M    M
 10500    2.4  36.3   190   21   11   6.3   3.5   19.9  67.7     1.4      M    M
 10250    2.8  37.0   190   20   10   8.1   4.4   19.6  67.3     1.1      M    M
 10000    3.4  38.1   185   18    9   8.7   4.8   19.6  67.2     1.0      M    M
  9750    4.0  39.2   180   17    9   8.7   4.8   19.4  67.0     0.9      M    M
  9500    4.5  40.1   175   17    9   9.8   5.4   19.4  67.0     0.7      M    M
  9250    5.2  41.4   170   16    8   9.6   5.3   19.4  66.9     0.7      M    M
  9000    5.9  42.6   160   16    8   9.7   5.3   19.4  66.9     0.7      M    M
  8750    6.6  43.9   160   16    8   9.7   5.3   19.4  66.9     0.6      M    M
  8500    7.3  45.1   160   16    8   9.6   5.3   19.4  66.9     0.6      M    M
  8250    8.0  46.4   165   15    8   9.9   5.4   19.4  66.9     0.6      M    M
  8000    8.7  47.7   165   15    8   8.9   4.9   19.4  66.9     0.5      M    M
  7750    9.4  48.9   165   15    8  12.6   6.9   19.4  66.9     0.5      M    M
  7500   10.0  50.0   165   15    8  -6.0  -3.3   19.2  66.6     0.4      M    M
  7250    8.5  47.3   160   15    8 -14.5  -8.0   17.2  63.0    -1.8    156  0.8
  7000    8.2  46.8   160   15    8   1.8   1.0   16.2  61.1    -2.9    158  0.8
  6750    8.5  47.3   155   14    7   3.4   1.9   15.6  60.1    -3.3    143  0.7
  6500    8.9  48.0   145   13    6   6.7   3.7   15.2  59.4    -3.7    123  0.6
  6250    9.5  49.1   135   12    6   8.9   4.9   15.1  59.2    -3.8     98  0.5
  6000   10.1  50.2   125   11    6   8.1   4.5   15.0  59.0    -4.0     73  0.4
  5750   10.7  51.3   120   10    5   8.9   4.9   14.9  58.9    -4.1     47  0.2
  5500   11.3  52.3   115    9    5   6.5   3.6   14.8  58.7    -4.2     22  0.1
  5250   11.5  52.7   115    8    4   2.1   1.2   14.4  57.9    -4.7      7  0.0
  5000   11.4  52.5   110    7    4  -6.6  -3.6   13.6  56.4    -5.6      4  0.0

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

           09/29/2014 at 0900 MDT          |       09/29/2014 at 1200 MDT
                                           |
K index... +13.4  LI... -1.6               | K index... +22.6  LI... -2.6
CAPE... +238.4  CIN... -47.2               | CAPE... +388.4  CIN... -2.3
                                           |
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 -58.2 -72.8  230  34 18   2.9   1.6 | -57.8 -72.0  230  29 15   3.1   1.7
 45000 -53.7 -64.7  230  53 27   2.8   1.6 | -52.8 -63.0  230  45 23   3.7   2.0
 40000 -49.4 -56.9  230  71 37   2.9   1.6 | -47.3 -53.1  220  61 31   3.6   2.0
 38000 -48.4 -55.1  225  78 40   1.3   0.7 | -46.8 -52.2  215  68 35  -0.1  -0.0
 36000 -47.6 -53.7  220  84 43   1.3   0.7 | -46.8 -52.2  210  75 39  -0.1  -0.0
 34000 -46.0 -50.8  220  88 45   5.3   2.9 | -46.1 -51.0  205  79 41   3.8   2.1
 32000 -42.8 -45.0  215  85 44   5.3   2.9 | -43.6 -46.5  205  76 39   3.8   2.1
 30000 -38.6 -37.5  215  80 41   7.8   4.3 | -40.3 -40.5  205  71 36   7.9   4.3
 29000 -36.3 -33.3  215  76 39   7.8   4.3 | -37.9 -36.2  205  66 34   7.9   4.3
 28000 -33.9 -29.0  215  71 37   7.8   4.3 | -35.5 -31.9  205  62 32   7.9   4.3
 27000 -31.7 -25.1  215  67 35   6.2   3.4 | -33.2 -27.8  205  58 30   7.9   4.3
 26000 -29.9 -21.8  215  63 32   6.3   3.5 | -30.8 -23.4  205  56 29   7.9   4.4
 25000 -28.0 -18.4  215  58 30   6.3   3.5 | -28.5 -19.3  205  54 28   8.0   4.4
 24000 -26.1 -15.0  215  54 28   6.0   3.3 | -26.2 -15.2  205  52 27   6.0   3.3
 23000 -24.3 -11.7  210  51 26   5.9   3.2 | -24.5 -12.1  205  50 26   5.5   3.0
 22000 -22.5  -8.5  210  48 25   5.9   3.2 | -22.9  -9.2  205  48 25   5.5   3.0
 21000 -20.6  -5.1  210  45 23   7.7   4.2 | -21.1  -6.0  205  46 24   7.7   4.2
 20000 -18.3  -0.9  210  43 22   7.6   4.2 | -18.8  -1.8  200  44 22   7.5   4.1
 19500 -17.2   1.0  210  42 22   7.6   4.2 | -17.6   0.3  200  42 22   7.6   4.1
 19000 -16.0   3.2  210  41 21   7.7   4.2 | -16.5   2.3  200  41 21   7.7   4.2
 18500 -15.0   5.0  210  40 20   5.7   3.1 | -15.4   4.3  200  40 21   5.5   3.0
 18000 -14.2   6.4  210  38 20   5.5   3.0 | -14.7   5.5  205  40 20   5.2   2.9
 17500 -13.3   8.1  205  37 19   5.8   3.2 | -13.9   7.0  205  39 20   5.3   2.9
 17000 -12.4   9.7  205  37 19   6.3   3.4 | -13.1   8.4  205  38 20   5.4   3.0
 16500 -11.5  11.3  210  36 19   6.3   3.5 | -12.3   9.9  205  36 19   5.3   2.9
 16000 -10.6  12.9  210  35 18   6.2   3.4 | -11.4  11.5  205  34 18   6.8   3.7
 15500  -9.7  14.5  210  33 17   6.2   3.4 | -10.5  13.1  210  32 16   6.8   3.7
 15000  -8.3  17.1  210  31 16   6.7   3.7 |  -9.0  15.8  210  29 15   7.5   4.1
 14500  -7.3  18.9  210  29 15   6.7   3.7 |  -7.9  17.8  210  27 14   7.5   4.1
 14000  -6.3  20.7  210  28 14   7.8   4.3 |  -6.8  19.8  210  25 13   9.2   5.1
 13500  -5.2  22.6  210  27 14   7.7   4.2 |  -5.5  22.1  210  24 13   9.2   5.0
 13000  -4.0  24.8  210  25 13   8.6   4.7 |  -4.2  24.4  210  23 12   9.1   5.0
 12500  -2.7  27.1  210  25 13   8.7   4.7 |  -2.9  26.8  210  22 12   9.2   5.0
 12000  -1.4  29.5  205  24 12   8.7   4.8 |  -1.7  28.9  205  21 11   8.4   4.6
 11500  -0.2  31.6  205  23 12   8.8   4.8 |  -0.5  31.1  205  20 10   8.3   4.6
 11000   1.0  33.8  205  22 12   8.1   4.4 |   0.7  33.3  205  18  9   7.6   4.2
 10500   2.2  36.0  200  22 11   7.4   4.1 |   1.8  35.2  205  17  9   6.8   3.7
 10250   2.8  37.0  200  22 11  10.8   5.9 |   2.4  36.3  205  16  8  10.6   5.8
 10000   3.6  38.5  200  21 11  11.5   6.3 |   3.3  37.9  205  15  8  11.4   6.3
  9750   4.3  39.7  200  21 11   8.6   4.7 |   4.0  39.2  205  14  7   8.1   4.5
  9500   5.0  41.0  200  21 11   9.6   5.3 |   4.6  40.3  205  13  7   9.2   5.0
  9250   5.6  42.1  200  21 11   8.6   4.7 |   5.3  41.5  205  13  7   8.4   4.6
  9000   6.2  43.2  195  21 11   8.9   4.9 |   5.9  42.6  205  12  6   9.1   5.0
  8750   7.0  44.6  195  20 11   9.9   5.4 |   6.6  43.9  205  11  6  10.1   5.5
  8500   7.7  45.9  195  20 10   9.5   5.2 |   7.3  45.1  205  10  5   9.8   5.4
  8250   8.4  47.1  195  20 10   9.8   5.4 |   8.1  46.6  205   9  5  10.2   5.6
  8000   9.0  48.2  195  20 10   8.6   4.7 |   8.8  47.8  205   9  5   9.9   5.4
  7750   9.6  49.3  190  19 10   7.2   4.0 |   9.5  49.1  205   9  5   9.1   5.0
  7500  10.1  50.2  190  19 10   6.9   3.8 |  10.2  50.4  210   9  5   9.7   5.3
  7250  10.6  51.1  185  19 10   6.2   3.4 |  11.0  51.8  210   9  5  10.8   5.9
  7000  11.0  51.8  180  18  9   5.7   3.1 |  11.8  53.2  210   9  4  10.5   5.7
  6750  11.3  52.3  175  17  9   5.6   3.1 |  12.5  54.5  210   8  4   8.9   4.9
  6500  11.7  53.1  170  16  8   3.5   1.9 |  13.2  55.8  210   8  4   9.8   5.4
  6250  11.8  53.2  165  14  7   1.9   1.0 |  14.0  57.2  210   8  4  11.1   6.1
  6000  11.9  53.4  160  11  6   1.8   1.0 |  14.8  58.6  210   8  4  10.4   5.7
  5750  12.0  53.6  150   9  4   3.3   1.8 |  15.5  59.9  215   7  4  10.6   5.8
  5500  12.3  54.1  145   7  4   6.8   3.7 |  16.4  61.5  215   7  4  12.1   6.7
  5250  12.8  55.0  145   7  4   7.3   4.0 |  17.3  63.1  215   7  4  12.9   7.1
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/29/2014 at 1500 MDT          |       09/29/2014 at 1800 MDT
                                           |
K index... +19.8  LI... -2.3               | K index... +24.5  LI... -0.0
CAPE... +365.7  CIN... -3.6                | CAPE... +44.5  CIN... -34.9
                                           |
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 -56.7 -70.1  235  31 16   4.0   2.2 | -57.2 -71.0  250  33 17   3.6   2.0
 45000 -50.9 -59.6  235  38 19   3.0   1.7 | -51.8 -61.2  260  36 19   2.5   1.4
 40000 -46.3 -51.3  230  40 21   3.0   1.6 | -48.0 -54.4  265  34 17   2.5   1.4
 38000 -45.5 -49.9  220  41 21   0.7   0.4 | -46.5 -51.7  260  32 16   2.4   1.3
 36000 -45.1 -49.2  210  42 22   0.7   0.4 | -45.1 -49.2  255  29 15   2.4   1.3
 34000 -44.8 -48.6  205  44 22   0.5   0.3 | -44.0 -47.2  240  27 14  -0.3  -0.2
 32000 -44.4 -47.9  195  46 23   0.5   0.3 | -44.3 -47.7  220  25 13  -0.4  -0.2
 30000 -42.8 -45.0  190  44 23   6.8   3.7 | -43.0 -45.4  210  24 12   7.3   4.0
 29000 -40.8 -41.4  190  41 21   6.8   3.7 | -40.8 -41.4  210  22 11   7.3   4.0
 28000 -38.7 -37.7  190  37 19   6.8   3.7 | -38.6 -37.5  215  20 10   7.3   4.0
 27000 -36.5 -33.7  195  33 17   9.6   5.2 | -36.4 -33.5  220  18  9   8.4   4.6
 26000 -33.7 -28.7  195  31 16   9.6   5.2 | -33.9 -29.0  230  17  9   8.4   4.6
 25000 -30.8 -23.4  200  30 15   9.6   5.3 | -31.4 -24.5  240  16  8   8.4   4.6
 24000 -28.0 -18.4  205  28 15   8.2   4.5 | -28.9 -20.0  250  16  8   8.3   4.6
 23000 -25.8 -14.4  205  32 16   7.5   4.1 | -26.4 -15.5  255  17  9   8.3   4.5
 22000 -23.5 -10.3  205  35 18   7.5   4.1 | -23.9 -11.0  255  18  9   8.3   4.5
 21000 -21.4  -6.5  205  37 19   6.6   3.6 | -21.5  -6.7  255  19 10   7.3   4.0
 20000 -19.4  -2.9  205  38 19   6.7   3.7 | -19.3  -2.7  255  19 10   7.4   4.0
 19500 -18.4  -1.1  205  38 20   6.7   3.7 | -18.2  -0.8  255  20 10   7.4   4.1
 19000 -17.4   0.7  205  38 20   6.7   3.7 | -17.2   1.0  255  20 10   7.4   4.1
 18500 -16.4   2.5  205  38 20   6.9   3.8 | -16.1   3.0  255  21 11   6.8   3.7
 18000 -15.3   4.5  205  39 20   6.9   3.8 | -15.1   4.8  250  21 11   6.6   3.6
 17500 -14.3   6.3  205  39 20   7.0   3.8 | -14.2   6.4  250  21 11   6.6   3.6
 17000 -13.2   8.2  205  38 20   7.2   3.9 | -13.2   8.2  250  21 11   6.3   3.5
 16500 -12.1  10.2  205  38 19   7.2   4.0 | -12.3   9.9  250  22 11   6.3   3.4
 16000 -11.1  12.0  205  36 19   6.6   3.6 | -11.3  11.7  250  22 11   6.9   3.8
 15500 -10.1  13.8  205  35 18   6.7   3.7 | -10.3  13.5  255  22 11   6.9   3.8
 15000  -8.6  16.5  200  32 17   7.1   3.9 |  -9.3  15.3  255  22 11   6.9   3.8
 14500  -7.6  18.3  200  31 16   7.1   3.9 |  -7.8  18.0  255  22 11   6.9   3.8
 14000  -6.6  20.1  200  30 15   7.7   4.2 |  -6.8  19.8  255  22 11   6.9   3.8
 13500  -5.5  22.1  200  28 14   7.8   4.3 |  -5.8  21.6  250  22 11   6.9   3.8
 13000  -4.4  24.1  200  27 14   7.5   4.1 |  -4.8  23.4  250  22 11   7.1   3.9
 12500  -3.4  25.9  200  24 13   7.5   4.1 |  -3.7  25.3  250  21 11   7.1   3.9
 12000  -2.4  27.7  200  22 11   7.1   3.9 |  -2.7  27.1  250  21 11   7.2   4.0
 11500  -1.4  29.5  205  20 10   7.1   3.9 |  -1.6  29.1  250  20 10   7.3   4.0
 11000  -0.4  31.3  210  17  9   5.9   3.2 |  -0.7  30.7  245  19 10   5.9   3.3
 10500   0.4  32.7  215  15  8   4.9   2.7 |   0.2  32.4  245  17  9   5.0   2.7
 10250   0.8  33.4  215  14  7   8.8   4.8 |   0.6  33.1  240  16  8   8.6   4.7
 10000   1.6  34.9  220  13  7   9.7   5.3 |   1.3  34.3  240  15  8  10.0   5.5
  9750   2.2  36.0  225  12  6   6.3   3.5 |   1.9  35.4  240  14  7   7.3   4.0
  9500   2.7  36.9  230  11  6   7.3   4.0 |   2.5  36.5  235  14  7   8.2   4.5
  9250   3.2  37.8  240  10  5   6.6   3.6 |   3.1  37.6  235  13  7   7.4   4.0
  9000   3.6  38.5  245  10  5   6.7   3.7 |   3.6  38.5  230  12  6   8.2   4.5
  8750   4.2  39.6  255  10  5   7.4   4.1 |   4.3  39.7  230  12  6   9.3   5.1
  8500   4.7  40.5  265  10  5   7.1   3.9 |   4.9  40.8  230  11  6   9.0   5.0
  8250   5.2  41.4  275  10  5   8.4   4.6 |   5.6  42.1  230  10  5   8.6   4.7
  8000   5.9  42.6  280  11  5   9.0   4.9 |   6.2  43.2  225  10  5   7.3   4.0
  7750   6.5  43.7  285  11  6   8.0   4.4 |   6.7  44.1  225   9  4   6.6   3.6
  7500   7.0  44.6  290  12  6   8.6   4.7 |   7.1  44.8  220   8  4   6.1   3.3
  7250   7.7  45.9  290  12  6   9.8   5.4 |   7.5  45.5  215   6  3   5.2   2.9
  7000   8.4  47.1  295  13  7  10.0   5.5 |   7.9  46.2  210   5  2   4.8   2.6
  6750   9.1  48.4  295  13  7   9.3   5.1 |   8.2  46.8  195   3  2   3.8   2.1
  6500   9.8  49.6  295  13  7  10.2   5.6 |   8.5  47.3  170   2  1   5.8   3.2
  6250  10.6  51.1  295  13  7  11.4   6.3 |   9.0  48.2  155   2  1   8.0   4.4
  6000  11.4  52.5  295  13  6  10.1   5.6 |   9.5  49.1  135   2  1   7.5   4.1
  5750  12.2  54.0  295  12  6   9.4   5.1 |  10.0  50.0  125   2  1   7.8   4.3
  5500  12.9  55.2  295  12  6  10.9   6.0 |  10.6  51.1  125   2  1   7.7   4.2
  5250  13.7  56.7  295  12  6  12.1   6.6 |  11.2  52.2  120   1  1   7.7   4.2
  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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