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694
UXUS97 KGJT 301230
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0630 MDT Tuesday, September 30, 2014

This forecast is for Tuesday, September 30, 2014:

If the trigger temperature of 61.2 F/16.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 608 ft/min (3.1 m/s)
   Maximum height of thermals.................. 14036 ft MSL (9197 ft AGL)

Forecast maximum temperature................... 66.0 F/19.3 C
Time of trigger temperature.................... 1145 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................. 8285 ft MSL (3446 ft AGL)
Thermal soaring outlook for Wednesday 10/01.... Good

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

Remarks...

Sunrise/Sunset.................... 07:09:16 / 18:59:48 MDT
Total possible sunshine........... 11 hr 50 min 32 sec (710 min 32 sec)
Altitude of sun at 13:04:03 MDT... 47.90 degrees

Upper air data from rawinsonde observation taken on 09/30/2014 at 0600 MDT

Freezing level.................. 10575 ft MSL (5736 ft AGL)
Convective condensation level... 11214 ft MSL (6375 ft AGL)
Lifted condensation level....... 11837 ft MSL (6998 ft AGL)
Lifted index.................... +4.4
K index......................... +18.0

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  -59.9 -75.8   265   41   21   5.5   3.0   98.6 209.5    45.7      M    M
 45000  -54.2 -65.6   270   40   20   7.8   4.3   82.3 180.2    39.1      M    M
 40000  -53.9 -65.0   285   59   30   1.7   0.9   60.0 140.0    27.1      M    M
 38000  -54.8 -66.6   290   62   32   2.4   1.3   50.0 122.0    21.0      M    M
 36000  -51.4 -60.5   295   64   33   8.1   4.5   46.2 115.2    19.0      M    M
 34000  -46.6 -51.9   300   67   34   7.9   4.3   44.9 112.8    18.5      M    M
 32000  -41.8 -43.2   300   63   32   8.3   4.6   42.6 108.6    17.3      M    M
 30000  -36.2 -33.2   300   61   31   8.6   4.7   42.2 107.9    17.5      M    M
 29000  -34.1 -29.4   300   60   31   6.0   3.3   41.2 106.1    16.9      M    M
 28000  -31.8 -25.2   295   58   30   8.2   4.5   40.3 104.5    16.5      M    M
 27000  -29.3 -20.7   295   57   29   8.5   4.7   39.8 103.6    16.2      M    M
 26000  -26.9 -16.4   290   56   29   7.6   4.2   39.0 102.3    15.9      M    M
 25000  -24.6 -12.3   290   55   28   7.6   4.2   38.3 100.9    15.4      M    M
 24000  -22.6  -8.7   290   53   27   5.1   2.8   37.1  98.7    14.7      M    M
 23000  -21.0  -5.8   290   51   26   5.2   2.8   35.5  95.9    13.6      M    M
 22000  -18.5  -1.3   290   50   26   9.8   5.4   34.9  94.9    13.2      M    M
 21000  -16.3   2.7   295   47   24   7.7   4.2   34.1  93.3    12.7      M    M
 20000  -14.0   6.8   300   44   23   7.4   4.1   33.3  91.9    12.2      M    M
 19500  -12.9   8.8   305   41   21   5.5   3.0   32.9  91.2    11.9      M    M
 19000  -12.7   9.1   310   37   19   0.2   0.1   31.4  88.6    10.7      M    M
 18500  -12.4   9.7   310   37   19   5.3   2.9   30.2  86.4     9.6      M    M
 18000  -11.6  11.1   310   34   17   5.7   3.1   29.5  85.1     9.0      M    M
 17500  -10.4  13.3   305   29   15   2.7   1.5   28.3  82.9     8.0      M    M
 17000  -10.1  13.8   305   25   13   2.2   1.2   27.0  80.6     6.9      M    M
 16500   -9.7  14.5   290   22   11   5.3   2.9   25.8  78.5     5.9      M    M
 16000   -8.8  16.2   280   20   10   9.5   5.2   25.2  77.4     5.4      M    M
 15500  -12.0  10.4   265   23   12 -20.7 -11.4   20.1  68.2     0.7      M    M
 15000  -10.7  12.7   260   25   13   6.9   3.8   20.0  68.0     0.6      M    M
 14500   -9.4  15.1   265   26   13   8.5   4.6   19.9  67.7     0.5      M    M
 14000   -8.5  16.7   265   26   13   6.5   3.6   19.2  66.6    -0.2    802  4.1
 13500   -7.3  18.9   270   23   12   8.5   4.7   19.1  66.3    -0.4    749  3.8
 13000   -6.0  21.2   275   20   10   8.7   4.8   18.9  66.0    -0.6    697  3.5
 12500   -4.8  23.4   270   19   10   8.4   4.6   18.7  65.7    -0.8    644  3.3
 12000   -3.5  25.7   270   18    9   8.3   4.6   18.5  65.3    -1.0    593  3.0
 11500   -2.3  27.9   270   17    9   8.3   4.6   18.2  64.8    -1.2    541  2.7
 11000   -1.0  30.2   265   17    9   8.3   4.5   18.0  64.3    -1.5    489  2.5
 10500    0.2  32.4   260   16    8   8.2   4.5   17.7  63.9    -1.7    437  2.2
 10250    0.8  33.4   260   16    8   8.5   4.7   17.6  63.8    -1.8    411  2.1
 10000    1.5  34.7   260   16    8   9.3   5.1   17.6  63.7    -1.9    383  1.9
  9750    2.2  36.0   260   16    8   8.6   4.7   17.5  63.6    -1.9    356  1.8
  9500    2.7  36.9   260   15    8   7.8   4.3   17.4  63.3    -2.1    332  1.7
  9250    3.3  37.9   260   15    8   8.1   4.4   17.3  63.1    -2.3    308  1.6
  9000    3.8  38.8   260   15    8   8.1   4.5   17.1  62.8    -2.5    284  1.4
  8750    4.4  39.9   260   14    7   8.6   4.7   17.0  62.6    -2.6    258  1.3
  8500    5.0  41.0   260   13    7   7.2   3.9   16.9  62.4    -2.7    233  1.2
  8250    5.5  41.9   255   12    6   6.0   3.3   16.6  61.9    -3.0    212  1.1
  8000    5.9  42.6   255   11    6   6.3   3.5   16.4  61.5    -3.3    191  1.0
  7750    6.4  43.5   235    9    5   6.2   3.4   16.1  60.9    -3.6    169  0.9
  7500    6.9  44.4   210    9    5   6.2   3.4   15.8  60.5    -3.9    148  0.8
  7250    7.3  45.1   185   10    5   6.5   3.5   15.5  60.0    -4.1    127  0.6
  7000    7.8  46.0   170   13    7   5.5   3.0   15.3  59.5    -4.4    106  0.5
  6750    8.1  46.6   160   15    8   2.6   1.5   14.8  58.7    -4.9     90  0.5
  6500    8.2  46.8   155   16    8   1.6   0.9   14.2  57.6    -5.5     80  0.4
  6250    8.3  46.9   155   18    9   1.9   1.1   13.6  56.5    -6.1     69  0.3
  6000    8.4  47.1   150   20   10   1.7   1.0   13.0  55.5    -6.8     58  0.3
  5750    8.5  47.3   150   18    9   2.2   1.2   12.4  54.4    -7.4     47  0.2
  5500    8.5  47.3   145   15    7  -3.6  -2.0   11.7  53.1    -8.1     40  0.2
  5250    8.0  46.4   140   11    6  -5.3  -2.9   10.5  50.9    -9.4     47  0.2
  5000    8.0  46.4   135    8    4   7.7   4.2    9.8  49.7   -10.1     39  0.2

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

           09/30/2014 at 0900 MDT          |       09/30/2014 at 1200 MDT
                                           |
K index... +15.9  LI... +4.6               | K index... +14.7  LI... +2.1
CAPE... +20.0  CIN... -4.5                 | CAPE... +40.8  CIN... -4.2
                                           |
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 -60.1 -76.2  270  24 12   2.4   1.3 | -60.4 -76.7  265  25 13   2.4   1.3
 45000 -56.4 -69.5  275  34 17   1.8   1.0 | -56.7 -70.1  275  34 18   2.4   1.3
 40000 -53.8 -64.8  275  45 23   1.6   0.9 | -52.9 -63.2  270  48 25   2.4   1.3
 38000 -51.7 -61.1  275  51 26   3.7   2.1 | -51.3 -60.3  270  54 28   2.8   1.5
 36000 -49.5 -57.1  275  57 29   3.7   2.1 | -49.6 -57.3  275  60 31   2.8   1.5
 34000 -46.3 -51.3  275  59 30   7.4   4.0 | -46.6 -51.9  275  61 31   7.8   4.3
 32000 -41.9 -43.4  275  55 29   7.3   4.0 | -42.0 -43.6  275  56 29   7.7   4.2
 30000 -36.5 -33.7  275  52 27   8.8   4.8 | -37.2 -35.0  270  52 27   8.4   4.6
 29000 -33.8 -28.8  275  50 26   8.8   4.8 | -34.0 -29.2  270  51 26   8.5   4.6
 28000 -31.2 -24.2  280  49 25   8.8   4.8 | -31.5 -24.7  270  50 26   8.4   4.6
 27000 -28.8 -19.8  280  47 24   7.5   4.1 | -29.1 -20.4  270  48 25   7.6   4.2
 26000 -26.6 -15.9  280  46 24   7.5   4.1 | -26.8 -16.2  270  46 24   7.6   4.2
 25000 -24.3 -11.7  280  45 23   7.5   4.1 | -24.6 -12.3  270  44 23   7.6   4.2
 24000 -22.2  -8.0  280  43 22   6.1   3.4 | -22.4  -8.3  275  42 22   6.0   3.3
 23000 -20.3  -4.5  285  41 21   6.3   3.4 | -20.6  -5.1  275  40 20   6.2   3.4
 22000 -18.4  -1.1  285  39 20   6.3   3.4 | -18.8  -1.8  275  37 19   6.2   3.4
 21000 -16.5   2.3  285  37 19   7.3   4.0 | -17.0   1.4  275  35 18   5.8   3.2
 20000 -14.3   6.3  290  35 18   7.2   4.0 | -15.3   4.5  275  32 17   5.8   3.2
 19500 -13.2   8.2  290  35 18   7.2   4.0 | -14.4   6.1  275  31 16   5.8   3.2
 19000 -12.2  10.0  290  34 18   7.4   4.0 | -13.5   7.7  275  30 16   5.8   3.2
 18500 -11.2  11.8  290  33 17   5.5   3.0 | -12.7   9.1  275  29 15   6.0   3.3
 18000 -10.4  13.3  290  32 16   5.4   3.0 | -11.9  10.6  275  28 15   6.2   3.4
 17500  -9.6  14.7  290  30 16   5.2   2.8 | -11.0  12.2  275  28 14   6.6   3.6
 17000  -8.9  16.0  290  29 15   4.6   2.5 |  -9.9  14.2  280  27 14   7.3   4.0
 16500  -8.2  17.2  290  27 14   5.0   2.7 |  -8.8  16.2  280  26 13   7.8   4.3
 16000  -7.7  18.1  285  25 13   0.9   0.5 |  -8.0  17.6  280  25 13   2.8   1.5
 15500  -7.6  18.3  280  24 12   1.1   0.6 |  -7.5  18.5  280  24 12   3.2   1.8
 15000  -7.5  18.5  280  23 12   2.1   1.1 |  -7.0  19.4  280  23 12   2.4   1.3
 14500  -6.9  19.6  275  23 12   2.3   1.3 |  -6.7  19.9  275  23 12   2.2   1.2
 14000  -6.4  20.5  275  22 12   5.6   3.1 |  -6.1  21.0  270  23 12   5.7   3.1
 13500  -5.6  21.9  270  22 11   5.6   3.1 |  -5.3  22.5  270  22 11   5.4   3.0
 13000  -4.8  23.4  270  21 11   6.1   3.3 |  -4.5  23.9  265  21 11   6.4   3.5
 12500  -4.0  24.8  270  20 10   6.1   3.4 |  -3.6  25.5  265  20 10   6.5   3.6
 12000  -3.1  26.4  275  19 10   6.7   3.7 |  -2.6  27.3  260  19 10   7.1   3.9
 11500  -2.1  28.2  275  18  9   6.8   3.7 |  -1.6  29.1  260  18  9   7.3   4.0
 11000  -1.2  29.8  275  17  9   6.5   3.6 |  -0.6  30.9  260  17  9   6.4   3.5
 10500  -0.2  31.6  270  16  8   5.9   3.2 |   0.3  32.5  260  17  9   5.5   3.0
 10250   0.2  32.4  270  16  8   8.7   4.8 |   0.8  33.4  260  17  9   9.3   5.1
 10000   1.0  33.8  270  15  8   9.4   5.2 |   1.6  34.9  255  17  9   9.8   5.4
  9750   1.5  34.7  265  15  8   7.0   3.9 |   2.1  35.8  255  16  8   6.4   3.5
  9500   2.0  35.6  265  14  7   7.9   4.3 |   2.6  36.7  255  16  8   7.4   4.1
  9250   2.6  36.7  265  14  7   7.0   3.8 |   3.1  37.6  255  16  8   6.9   3.8
  9000   3.1  37.6  260  13  7   7.2   3.9 |   3.6  38.5  255  14  7   6.7   3.7
  8750   3.6  38.5  260  12  6   7.9   4.3 |   4.0  39.2  255  13  7   6.8   3.7
  8500   4.2  39.6  255  11  6   7.8   4.3 |   4.5  40.1  255  11  6   6.8   3.7
  8250   4.8  40.6  255  10  5   7.0   3.8 |   5.0  41.0  250   9  5   7.3   4.0
  8000   5.2  41.4  250   9  5   6.0   3.3 |   5.5  41.9  250   8  4   7.7   4.2
  7750   5.7  42.3  240   8  4   6.1   3.3 |   6.1  43.0  245   7  3   7.3   4.0
  7500   6.1  43.0  225   7  4   5.8   3.2 |   6.6  43.9  240   6  3   8.2   4.5
  7250   6.6  43.9  210   7  4   5.5   3.0 |   7.3  45.1  235   5  3  10.3   5.6
  7000   7.0  44.6  200   8  4   5.0   2.7 |   8.1  46.6  235   5  3  10.4   5.7
  6750   7.3  45.1  190   8  4   3.9   2.2 |   8.8  47.8  235   5  2   9.0   4.9
  6500   7.5  45.5  180   9  5   3.0   1.7 |   9.5  49.1  235   5  2  10.0   5.5
  6250   7.7  45.9  175   9  4   2.9   1.6 |  10.3  50.5  235   5  2  11.5   6.3
  6000   7.9  46.2  170   8  4   2.4   1.3 |  11.1  52.0  235   5  2  10.6   5.8
  5750   8.1  46.6  165   7  4   3.9   2.1 |  11.9  53.4  235   4  2  11.2   6.2
  5500   8.5  47.3  160   6  3   7.0   3.8 |  12.8  55.0  235   4  2  13.1   7.2
  5250   9.1  48.4  160   5  3   7.1   3.9 |  13.8  56.8  240   4  2  13.6   7.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/30/2014 at 1500 MDT          |       09/30/2014 at 1800 MDT
                                           |
K index... +20.5  LI... -1.0               | K index... +19.5  LI... -0.7
CAPE... +45.4  CIN... -15.2                | CAPE... +12.7  CIN... -51.4
                                           |
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 -60.2 -76.4  260  28 14   2.2   1.2 | -58.7 -73.7  255  33 17   2.8   1.5
 45000 -56.7 -70.1  265  38 19   2.9   1.6 | -54.6 -66.3  255  41 21   2.1   1.2
 40000 -52.1 -61.8  260  50 26   2.9   1.6 | -51.3 -60.3  260  52 27   2.1   1.1
 38000 -50.2 -58.4  260  54 28   3.3   1.8 | -49.9 -57.8  265  50 26   2.4   1.3
 36000 -48.2 -54.8  260  58 30   3.3   1.8 | -48.4 -55.1  275  48 25   2.4   1.3
 34000 -45.7 -50.3  260  59 31   5.5   3.0 | -46.1 -51.0  280  48 25   6.0   3.3
 32000 -42.4 -44.3  255  56 29   5.5   3.0 | -42.6 -44.7  280  48 25   6.0   3.3
 30000 -38.5 -37.3  255  52 27   8.5   4.7 | -38.8 -37.8  280  46 24   6.8   3.8
 29000 -35.3 -31.5  260  50 26   8.5   4.7 | -36.8 -34.2  280  43 22   6.9   3.8
 28000 -32.7 -26.9  260  48 25   8.5   4.7 | -34.2 -29.6  280  40 20   6.9   3.8
 27000 -30.3 -22.5  260  46 24   7.9   4.3 | -32.1 -25.8  280  37 19   7.4   4.1
 26000 -27.9 -18.2  265  44 23   7.9   4.3 | -29.9 -21.8  280  36 18   7.4   4.1
 25000 -25.6 -14.1  265  42 21   7.9   4.3 | -27.7 -17.9  280  34 18   7.4   4.1
 24000 -23.4 -10.1  265  40 20   5.5   3.0 | -25.5 -13.9  285  32 17   7.1   3.9
 23000 -21.8  -7.2  265  39 20   5.4   3.0 | -23.4 -10.1  285  30 16   7.1   3.9
 22000 -20.2  -4.4  270  38 20   5.4   3.0 | -21.3  -6.3  290  28 15   7.2   4.0
 21000 -18.6  -1.5  270  37 19   4.9   2.7 | -19.3  -2.7  290  27 14   5.6   3.0
 20000 -17.1   1.2  270  36 18   5.0   2.7 | -17.6   0.3  290  27 14   5.7   3.1
 19500 -16.4   2.5  275  35 18   4.9   2.7 | -16.8   1.8  290  27 14   5.7   3.1
 19000 -15.7   3.7  275  34 17   4.7   2.6 | -15.9   3.4  290  26 14   5.7   3.1
 18500 -14.7   5.5  275  33 17   8.4   4.6 | -15.0   5.0  290  26 14   6.5   3.6
 18000 -13.4   7.9  275  32 17   8.7   4.7 | -14.0   6.8  290  27 14   6.6   3.6
 17500 -12.1  10.2  280  31 16   8.6   4.7 | -13.1   8.4  285  27 14   7.2   3.9
 17000 -10.9  12.4  280  30 16   8.5   4.7 | -11.8  10.8  285  27 14   8.5   4.7
 16500  -9.6  14.7  280  29 15   8.9   4.9 | -10.5  13.1  285  27 14   8.7   4.8
 16000  -8.6  16.5  280  28 15   4.9   2.7 |  -9.4  15.1  285  26 14   7.2   3.9
 15500  -7.9  17.8  280  27 14   5.2   2.8 |  -8.3  17.1  285  26 14   7.4   4.1
 15000  -7.2  19.0  280  26 13   5.1   2.8 |  -7.3  18.9  285  26 13   6.4   3.5
 14500  -6.4  20.5  275  24 12   5.0   2.8 |  -6.4  20.5  285  25 13   6.1   3.4
 14000  -5.2  22.6  270  21 11   6.6   3.6 |  -5.6  21.9  285  24 13   6.5   3.6
 13500  -4.3  24.3  270  20 10   6.5   3.5 |  -4.1  24.6  280  22 11   6.9   3.8
 13000  -3.3  26.1  265  20 10   6.8   3.7 |  -3.0  26.6  280  21 11   7.9   4.4
 12500  -2.3  27.9  260  20 10   6.8   3.7 |  -1.9  28.6  270  20 10   8.0   4.4
 12000  -1.3  29.7  255  20 10   7.2   4.0 |  -0.7  30.7  265  20 10   8.5   4.7
 11500  -0.2  31.6  255  21 11   7.4   4.1 |   0.6  33.1  265  20 10   8.6   4.7
 11000   0.8  33.4  250  21 11   6.8   3.7 |   1.8  35.2  260  20 10   7.8   4.3
 10500   1.7  35.1  250  20 10   6.2   3.4 |   3.0  37.4  260  20 10   7.2   4.0
 10250   2.2  36.0  250  20 10   8.8   4.8 |   3.5  38.3  260  20 10   9.2   5.1
 10000   2.9  37.2  245  19 10   9.3   5.1 |   4.3  39.7  260  19 10   9.5   5.2
  9750   3.5  38.3  245  17  9   7.1   3.9 |   4.9  40.8  260  18 10   7.6   4.2
  9500   4.0  39.2  245  16  8   7.9   4.3 |   5.4  41.7  260  18  9   8.2   4.5
  9250   4.5  40.1  245  14  7   6.9   3.8 |   6.0  42.8  260  17  9   7.8   4.3
  9000   5.0  41.0  245  13  6   7.1   3.9 |   6.6  43.9  260  16  8   7.2   4.0
  8750   5.5  41.9  245  11  6   8.3   4.5 |   7.1  44.8  260  15  8   7.0   3.8
  8500   6.1  43.0  250  10  5   7.5   4.1 |   7.6  45.7  260  13  7   7.0   3.8
  8250   6.7  44.1  250   9  5   9.7   5.3 |   8.1  46.6  265  12  6   7.3   4.0
  8000   7.5  45.5  250   9  4  10.7   5.9 |   8.6  47.5  265  10  5   7.3   4.0
  7750   8.2  46.8  250   9  4   9.1   5.0 |   9.1  48.4  270   9  5   6.9   3.8
  7500   8.9  48.0  255   8  4   9.5   5.2 |   9.6  49.3  275   8  4   7.2   4.0
  7250   9.6  49.3  255   8  4  10.3   5.7 |  10.2  50.4  280   7  4   8.6   4.7
  7000  10.4  50.7  255   8  4  10.6   5.8 |  10.9  51.6  280   7  4   9.5   5.2
  6750  11.2  52.2  255   8  4   9.8   5.4 |  11.5  52.7  280   7  3   9.2   5.0
  6500  11.9  53.4  255   8  4  10.3   5.6 |  12.2  54.0  285   7  3   9.8   5.3
  6250  12.7  54.9  255   8  4  11.0   6.1 |  13.0  55.4  285   6  3  10.5   5.7
  6000  13.5  56.3  255   8  4  10.6   5.8 |  13.7  56.7  285   6  3  10.3   5.6
  5750  14.3  57.7  255   7  4  10.7   5.9 |  14.5  58.1  285   6  3   9.1   5.0
  5500  15.1  59.2  255   7  4  12.3   6.7 |  15.1  59.2  290   6  3   7.3   4.0
  5250  16.1  61.0  260   7  4  13.9   7.6 |  15.6  60.1  290   6  3   6.4   3.5
  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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NOAA National Weather Service
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Silver Spring, MD 20910
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Page last modified: May 16, 2007
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