Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 021240
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0640 MDT Tuesday, September 2, 2014

This forecast is for Tuesday, September 2, 2014:

If the trigger temperature of 81.5 F/27.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1004 ft/min (5.1 m/s)
   Maximum height of thermals.................. 16021 ft MSL (11182 ft AGL)

Forecast maximum temperature................... 89.0 F/32.1 C
Time of trigger temperature.................... 1115 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................. 11000 ft MSL (6161 ft AGL)
Thermal soaring outlook for Wednesday 09/03.... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:43:45 / 19:44:28 MDT
Total possible sunshine........... 13 hr 0 min 43 sec (780 min 43 sec)
Altitude of sun at 13:13:40 MDT... 58.61 degrees

Upper air data from rawinsonde observation taken on 09/02/2014 at 0600 MDT

Freezing level.................. 15080 ft MSL (10241 ft AGL)
Additional freezing levels...... 16350 ft MSL (11511 ft AGL)
                                 16467 ft MSL (11628 ft AGL)
Convective condensation level... 18615 ft MSL (13776 ft AGL)
Lifted condensation level....... 17135 ft MSL (12296 ft AGL)
Lifted index.................... +1.6
K index......................... +16.1

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  -67.0 -88.6   290   32   16   3.8   2.1   83.6 182.4    30.0      M    M
 45000  -62.0 -79.6   270   42   22   5.1   2.8   67.6 153.7    22.3      M    M
 40000  -53.8 -64.8   275   43   22   5.7   3.1   56.4 133.4    16.4      M    M
 38000  -52.2 -62.0   285   48   25   6.3   3.4   50.1 122.2    12.6      M    M
 36000  -47.5 -53.5   285   48   25   8.6   4.7   48.4 119.2    11.8      M    M
 34000  -42.6 -44.7   280   45   23   8.2   4.5   47.1 116.7    11.1      M    M
 32000  -37.2 -35.0   275   42   22   9.8   5.4   46.5 115.7    11.0      M    M
 30000  -31.3 -24.3   275   42   21   8.5   4.7   45.8 114.4    10.7      M    M
 29000  -28.7 -19.7   280   39   20   8.5   4.7   45.1 113.2    10.3      M    M
 28000  -26.2 -15.2   280   36   19   8.5   4.7   44.6 112.2    10.0      M    M
 27000  -23.7 -10.7   285   33   17   8.5   4.7   44.2 111.5     9.8      M    M
 26000  -21.1  -6.0   290   31   16   8.5   4.7   43.8 110.9     9.7      M    M
 25000  -18.6  -1.5   285   26   13   8.2   4.5   43.3 109.9     9.3      M    M
 24000  -16.5   2.3   285   24   12   5.8   3.2   42.2 107.9     8.5      M    M
 23000  -14.8   5.4   280   21   11   5.8   3.2   40.7 105.3     7.4      M    M
 22000  -12.8   9.0   275   19   10   8.6   4.7   39.7 103.5     6.7      M    M
 21000  -10.2  13.6   280   20   10   8.5   4.7   39.3 102.7     6.4      M    M
 20000   -7.7  18.1   265   21   11   6.5   3.5   38.8 101.9     6.1      M    M
 19500   -7.3  18.9   270   23   12   1.8   1.0   37.7  99.8     5.1      M    M
 19000   -6.8  19.8   270   24   12   6.3   3.4   36.5  97.8     4.1      M    M
 18500   -5.6  21.9   275   25   13   8.8   4.8   36.2  97.2     3.8      M    M
 18000   -4.3  24.3   275   26   13   8.7   4.8   36.0  96.8     3.7      M    M
 17500   -3.0  26.6   280   26   14   8.7   4.8   35.8  96.5     3.6      M    M
 17000   -1.7  28.9   280   27   14   9.0   4.9   35.7  96.2     3.4      M    M
 16500    0.2  32.4   285   28   15  -8.4  -4.6   35.4  95.7     3.2      M    M
 16000   -2.3  27.9   285   29   15   4.2   2.3   31.3  88.4    -0.8   1011  5.1
 15500   -0.9  30.4   285   30   15   9.2   5.1   31.3  88.3    -0.9    954  4.8
 15000    0.5  32.9   285   30   15   9.6   5.3   31.3  88.3    -0.9    898  4.6
 14500    1.9  35.4   285   31   16   9.6   5.3   31.3  88.3    -0.9    841  4.3
 14000    3.3  37.9   285   31   16   9.6   5.3   31.3  88.3    -1.0    784  4.0
 13500    4.7  40.5   285   30   15   9.6   5.3   31.2  88.2    -1.1    727  3.7
 13000    6.1  43.0   285   28   15   9.6   5.3   31.2  88.1    -1.2    670  3.4
 12500    7.5  45.5   280   27   14   9.6   5.3   31.2  88.1    -1.2    613  3.1
 12000    8.9  48.0   280   26   13   5.9   3.2   31.1  87.9    -1.3    559  2.8
 11500    9.5  49.1   290   20   10   3.8   2.1   30.1  86.1    -2.2    526  2.7
 11000   10.1  50.2   300   16    8   4.9   2.7   29.1  84.4    -3.0    493  2.5
 10500   11.3  52.3   295   12    6   9.2   5.0   28.8  83.8    -3.3    442  2.2
 10250   11.9  53.4   295   10    5   8.8   4.8   28.7  83.7    -3.4    415  2.1
 10000   12.5  54.5   290    9    5   8.8   4.8   28.7  83.6    -3.5    389  2.0
  9750   13.2  55.8   285    8    4   8.8   4.8   28.6  83.4    -3.6    363  1.8
  9500   13.8  56.8   280    6    3   8.8   4.8   28.5  83.3    -3.7    336  1.7
  9250   14.4  57.9   275    5    3   8.9   4.9   28.5  83.2    -3.8    310  1.6
  9000   15.1  59.2   260    4    2   8.9   4.9   28.4  83.1    -3.9    284  1.4
  8750   15.7  60.3   235    4    2   9.0   4.9   28.3  83.0    -4.0    257  1.3
  8500   16.3  61.3   205    4    2   8.6   4.7   28.3  82.9    -4.1    231  1.2
  8250   16.8  62.2   185    5    3   3.6   2.0   28.0  82.4    -4.4    209  1.1
  8000   16.9  62.4   175    7    3   0.3   0.1   27.3  81.2    -5.1    200  1.0
  7750   17.0  62.6   165    8    4   1.1   0.6   26.7  80.0    -5.7    190  1.0
  7500   17.0  62.6   160   10    5   1.1   0.6   26.0  78.8    -6.4    180  0.9
  7250   17.1  62.8   155   11    6   0.3   0.2   25.3  77.6    -7.1    171  0.9
  7000   17.2  63.0   150   13    7   3.5   1.9   24.7  76.4    -7.7    161  0.8
  6750   17.7  63.9   145   12    6   9.5   5.2   24.4  76.0    -8.0    139  0.7
  6500   18.2  64.8   140   11    6   1.7   0.9   24.3  75.7    -8.2    116  0.6
  6250   18.0  64.4   130   10    5  -1.7  -0.9   23.3  74.0    -9.2    115  0.6
  6000   18.2  64.8   125    9    5   6.8   3.7   22.8  73.1    -9.7    101  0.5
  5750   18.9  66.0   120    8    4  10.2   5.6   22.8  73.0    -9.8     74  0.4
  5500   19.5  67.1   120    8    4   5.1   2.8   22.7  72.8    -9.9     47  0.2
  5250   19.6  67.3   115    7    4   0.6   0.3   22.1  71.7   -10.6     37  0.2
  5000   19.3  66.7   115    6    3 -14.4  -7.9   21.0  69.9   -11.7     40  0.2

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

           09/02/2014 at 0900 MDT          |       09/02/2014 at 1200 MDT
                                           |
K index... +13.9  LI... +3.4               | K index... +15.4  LI... +3.2
CAPE... 0.0  CIN... -0.2                   | CAPE... 0.0  CIN... -0.4
                                           |
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 -66.0 -86.8  290  33 17   2.4   1.3 | -66.1 -87.0  300  29 15   2.1   1.1
 45000 -61.5 -78.7  290  37 19   4.8   2.6 | -61.7 -79.1  290  31 16   5.2   2.8
 40000 -53.9 -65.0  290  37 19   5.6   3.1 | -53.5 -64.3  280  35 18   5.2   2.9
 38000 -50.5 -58.9  285  38 20   5.6   3.1 | -50.4 -58.7  280  36 19   5.3   2.9
 36000 -47.2 -53.0  285  39 20   5.2   2.8 | -47.2 -53.0  275  37 19   4.8   2.6
 34000 -42.1 -43.8  285  37 19   8.9   4.9 | -42.0 -43.6  280  36 19   9.1   5.0
 32000 -36.8 -34.2  285  36 18   8.9   4.9 | -36.6 -33.9  280  36 18   9.1   5.0
 30000 -31.7 -25.1  285  34 17   8.5   4.7 | -31.4 -24.5  280  33 17   8.5   4.7
 29000 -29.2 -20.6  285  33 17   8.5   4.7 | -28.9 -20.0  280  32 16   8.5   4.7
 28000 -26.6 -15.9  285  32 16   8.4   4.6 | -26.3 -15.3  280  30 16   8.3   4.6
 27000 -24.2 -11.6  285  31 16   8.2   4.5 | -23.3  -9.9  280  29 15   8.1   4.5
 26000 -21.1  -6.0  285  30 15   8.2   4.5 | -20.8  -5.4  280  29 15   8.1   4.5
 25000 -18.7  -1.7  285  29 15   7.6   4.2 | -18.4  -1.1  280  28 14   7.5   4.1
 24000 -16.7   1.9  285  29 15   6.5   3.6 | -16.4   2.5  280  27 14   6.4   3.5
 23000 -14.7   5.5  285  28 14   6.5   3.6 | -14.5   5.9  285  25 13   6.4   3.5
 22000 -12.8   9.0  285  27 14   6.8   3.7 | -12.6   9.3  285  24 12   6.7   3.7
 21000 -10.7  12.7  285  26 13   7.2   4.0 | -10.5  13.1  280  23 12   7.1   3.9
 20000  -8.5  16.7  285  24 12   7.2   4.0 |  -8.4  16.9  280  22 11   7.1   3.9
 19500  -7.4  18.7  285  23 12   7.2   4.0 |  -7.3  18.9  280  22 11   7.2   3.9
 19000  -6.4  20.5  280  23 12   7.2   3.9 |  -6.3  20.7  275  22 11   6.4   3.5
 18500  -5.3  22.5  280  22 11   7.1   3.9 |  -5.4  22.3  275  22 11   6.5   3.5
 18000  -4.2  24.4  280  22 11   6.3   3.5 |  -4.4  24.1  270  22 12   6.0   3.3
 17500  -3.5  25.7  275  22 12   5.3   2.9 |  -3.6  25.5  270  23 12   5.5   3.0
 17000  -2.7  27.1  275  23 12   5.3   2.9 |  -2.8  27.0  265  23 12   5.6   3.0
 16500  -2.0  28.4  275  23 12   5.2   2.9 |  -2.0  28.4  265  23 12   6.3   3.5
 16000  -1.2  29.8  275  23 12   5.3   2.9 |  -1.1  30.0  265  22 12   6.3   3.5
 15500  -0.5  31.1  280  23 12   6.2   3.4 |  -0.2  31.6  265  22 11   7.5   4.1
 15000   0.4  32.7  280  22 11   6.6   3.6 |   0.9  33.6  265  21 11   7.9   4.3
 14500   1.3  34.3  280  22 11   7.5   4.1 |   2.1  35.8  270  20 10   8.0   4.4
 14000   2.6  36.7  285  21 11   9.2   5.0 |   3.2  37.8  270  18  9   8.2   4.5
 13500   3.9  39.0  285  21 11   9.2   5.0 |   5.0  41.0  270  16  8   8.6   4.7
 13000   5.9  42.6  285  20 10   8.9   4.9 |   6.3  43.3  270  16  8   8.8   4.8
 12500   7.2  45.0  285  19 10   8.9   4.9 |   7.6  45.7  265  15  8   9.1   5.0
 12000   8.5  47.3  280  18  9   8.8   4.8 |   9.0  48.2  265  15  8   9.3   5.1
 11500   9.8  49.6  275  17  9   8.4   4.6 |  10.3  50.5  260  15  8   8.9   4.9
 11000  10.9  51.6  270  15  8   7.5   4.1 |  11.6  52.9  255  14  7   8.2   4.5
 10500  12.1  53.8  265  13  7   4.0   2.2 |  12.8  55.0  250  14  7   5.2   2.8
 10250  12.2  54.0  260  12  6   4.3   2.4 |  13.1  55.6  245  13  7   5.9   3.2
 10000  12.9  55.2  260  11  5   9.1   5.0 |  13.8  56.8  245  12  6  10.4   5.7
  9750  13.5  56.3  255   9  5   8.1   4.5 |  14.5  58.1  240  11  6   9.8   5.4
  9500  14.1  57.4  245   8  4   7.3   4.0 |  15.2  59.4  235  10  5   7.8   4.3
  9250  14.5  58.1  240   7  4   6.1   3.4 |  15.7  60.3  230   9  5   6.0   3.3
  9000  15.0  59.0  235   6  3   7.0   3.8 |  16.2  61.2  220   8  4   7.2   4.0
  8750  15.5  59.9  225   6  3   7.0   3.9 |  16.7  62.1  215   8  4   7.2   4.0
  8500  16.0  60.8  215   5  3   7.2   4.0 |  17.3  63.1  205   7  4   6.9   3.8
  8250  16.6  61.9  205   6  3   7.7   4.2 |  17.7  63.9  200   7  3   6.6   3.6
  8000  17.1  62.8  195   6  3   6.6   3.6 |  18.2  64.8  190   6  3   6.5   3.6
  7750  17.6  63.7  185   7  4   5.4   2.9 |  18.7  65.7  185   6  3   6.5   3.6
  7500  17.9  64.2  180   8  4   3.2   1.7 |  19.2  66.6  185   5  3   7.3   4.0
  7250  18.0  64.4  170   8  4   1.8   1.0 |  19.7  67.5  180   5  3   7.7   4.2
  7000  18.2  64.8  165   9  4   1.5   0.8 |  20.3  68.5  180   5  2   8.0   4.4
  6750  18.2  64.8  160   9  5  -1.2  -0.5 |  20.9  69.6  180   5  2   9.6   5.3
  6500  18.0  64.4  155   8  4  -2.8  -1.6 |  21.6  70.9  180   4  2  10.6   5.8
  6250  17.8  64.0  145   7  4  -2.0  -1.1 |  22.4  72.3  180   4  2  11.2   6.2
  6000  17.6  63.7  135   7  3  -5.6  -3.1 |  23.3  73.9  180   4  2   9.6   5.3
  5750  17.1  62.8  115   6  3  -0.4  -0.2 |  24.0  75.2  185   4  2  11.1   6.1
  5500  17.6  63.7  115   5  3   8.9   4.9 |  24.9  76.8  185   4  2  14.3   7.8
  5250  18.0  64.4  110   5  3   1.5   0.9 |  25.9  78.6  185   4  2  11.7   6.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/02/2014 at 1500 MDT          |       09/02/2014 at 1800 MDT
                                           |
K index... +21.7  LI... +1.3               | K index... +20.6  LI... +1.1
CAPE... 0.0  CIN... -1.4                   | CAPE... 0.0  CIN... -29.5
                                           |
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 -65.3 -85.5  305  22 12   2.3   1.3 | -65.2 -85.4  305  20 10   2.6   1.4
 45000 -61.0 -77.8  300  26 14   4.5   2.5 | -60.4 -76.7  310  25 13   4.8   2.6
 40000 -53.7 -64.7  280  35 18   5.5   3.0 | -52.8 -63.0  290  30 15   5.1   2.8
 38000 -50.4 -58.7  275  33 17   5.5   3.0 | -49.7 -57.5  280  29 15   5.1   2.8
 36000 -47.1 -52.8  275  31 16   5.1   2.8 | -46.6 -51.9  275  29 15   4.8   2.7
 34000 -42.1 -43.8  270  32 17   8.7   4.8 | -42.1 -43.8  270  29 15   8.1   4.4
 32000 -36.9 -34.4  270  34 17   8.7   4.7 | -37.2 -35.0  270  29 15   8.0   4.4
 30000 -31.6 -24.9  270  32 16   8.9   4.9 | -32.0 -25.6  270  28 15   9.0   4.9
 29000 -29.0 -20.2  275  30 15   8.9   4.9 | -29.3 -20.7  270  28 14   9.0   4.9
 28000 -25.7 -14.3  275  28 15   8.2   4.5 | -26.0 -14.8  275  27 14   8.5   4.7
 27000 -23.2  -9.8  275  27 14   8.2   4.5 | -23.4 -10.1  275  26 13   8.5   4.7
 26000 -20.7  -5.3  275  26 14   8.2   4.5 | -20.9  -5.6  275  25 13   8.5   4.7
 25000 -18.3  -0.9  275  25 13   7.6   4.1 | -18.3  -0.9  275  24 13   7.9   4.3
 24000 -16.4   2.5  275  24 12   6.2   3.4 | -16.4   2.5  275  24 12   6.2   3.4
 23000 -14.5   5.9  275  23 12   6.3   3.4 | -14.5   5.9  275  23 12   6.3   3.4
 22000 -12.6   9.3  275  22 11   6.5   3.6 | -12.7   9.1  270  22 11   6.5   3.5
 21000 -10.6  12.9  270  22 11   6.9   3.8 | -10.7  12.7  265  23 12   6.8   3.7
 20000  -8.6  16.5  270  22 11   6.9   3.8 |  -8.7  16.3  260  23 12   6.8   3.7
 19500  -7.5  18.5  265  22 11   7.0   3.8 |  -7.7  18.1  260  23 12   6.7   3.7
 19000  -6.6  20.1  265  22 12   6.2   3.4 |  -6.6  20.1  255  24 12   7.5   4.1
 18500  -5.7  21.7  260  23 12   6.3   3.5 |  -5.5  22.1  255  24 12   7.5   4.1
 18000  -4.7  23.5  255  24 12   6.4   3.5 |  -4.5  23.9  250  25 13   7.5   4.1
 17500  -3.8  25.2  255  24 13   6.5   3.6 |  -3.4  25.9  245  25 13   7.5   4.1
 17000  -2.9  26.8  250  25 13   6.6   3.6 |  -2.4  27.7  245  25 13   7.6   4.2
 16500  -1.9  28.6  250  25 13   7.9   4.3 |  -1.3  29.7  245  25 13   8.3   4.6
 16000  -0.8  30.6  250  24 12   7.9   4.3 |  -0.1  31.8  240  24 13   8.3   4.6
 15500   0.3  32.5  245  24 12   8.5   4.7 |   1.1  34.0  240  24 12   8.7   4.7
 15000   1.5  34.7  245  22 12   8.7   4.8 |   2.4  36.3  240  23 12   8.8   4.8
 14500   2.7  36.9  245  21 11   8.8   4.8 |   3.7  38.7  240  22 11   8.9   4.9
 14000   4.0  39.2  245  20 10   9.0   4.9 |   5.0  41.0  245  21 11   9.0   5.0
 13500   6.0  42.8  245  18  9   9.1   5.0 |   7.0  44.6  245  20 10   8.9   4.9
 13000   7.4  45.3  245  17  9   9.1   5.0 |   8.3  46.9  245  19 10   8.8   4.8
 12500   8.7  47.7  245  15  8   8.9   4.9 |   9.6  49.3  245  18  9   8.7   4.8
 12000  10.0  50.0  245  14  7   8.6   4.7 |  10.9  51.6  245  17  9   8.5   4.6
 11500  11.3  52.3  250  13  7   8.5   4.6 |  12.1  53.8  250  17  9   8.1   4.5
 11000  12.5  54.5  250  12  6   8.1   4.4 |  13.2  55.8  250  16  8   7.4   4.1
 10500  13.8  56.8  250  11  6   5.3   2.9 |  14.3  57.7  250  15  8  10.3   5.6
 10250  14.1  57.4  250  10  5   6.0   3.3 |  15.2  59.4  255  14  7  10.7   5.9
 10000  14.8  58.6  255  10  5  10.0   5.5 |  15.8  60.4  255  14  7   7.0   3.9
  9750  15.5  59.9  255   9  5   9.6   5.3 |  16.4  61.5  255  13  7   8.1   4.4
  9500  16.1  61.0  255   9  5   7.3   4.0 |  16.9  62.4  255  12  6   7.6   4.2
  9250  16.6  61.9  255   8  4   6.1   3.3 |  17.5  63.5  255  12  6   7.6   4.2
  9000  17.1  62.8  260   7  4   8.2   4.5 |  18.1  64.6  255  11  6   7.8   4.3
  8750  17.7  63.9  260   6  3   7.9   4.3 |  18.6  65.5  260  10  5   7.8   4.3
  8500  18.3  64.9  265   5  3   8.0   4.4 |  19.2  66.6  260   9  5   7.6   4.2
  8250  18.9  66.0  265   5  2   8.1   4.5 |  19.7  67.5  260   7  4   7.1   3.9
  8000  19.5  67.1  270   4  2   9.1   5.0 |  20.3  68.5  265   6  3   6.8   3.7
  7750  20.2  68.4  270   4  2   9.7   5.3 |  20.7  69.3  265   5  2   6.0   3.3
  7500  20.9  69.6  270   4  2   9.8   5.4 |  21.2  70.2  270   4  2   8.2   4.5
  7250  21.6  70.9  270   4  2  10.2   5.6 |  21.9  71.4  270   4  2  10.6   5.8
  7000  22.4  72.3  270   4  2  10.0   5.5 |  22.7  72.9  270   3  2   9.5   5.2
  6750  23.1  73.6  270   4  2  10.2   5.6 |  23.3  73.9  270   3  2   9.1   5.0
  6500  23.9  75.0  270   4  2  10.6   5.8 |  24.0  75.2  270   3  2   9.8   5.4
  6250  24.7  76.5  270   4  2  11.3   6.2 |  24.8  76.6  270   3  2  10.2   5.6
  6000  25.5  77.9  270   4  2   9.4   5.2 |  25.5  77.9  270   3  2  10.1   5.5
  5750  26.2  79.2  270   4  2  11.0   6.1 |  26.3  79.3  270   3  2   9.4   5.2
  5500  27.2  81.0  270   4  2  15.1   8.3 |  26.9  80.4  270   3  2   8.5   4.6
  5250  28.3  82.9  275   4  2  12.8   7.0 |  27.5  81.5  270   3  2   8.6   4.7
  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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