Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 021241
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0640 MDT Tuesday, June 2, 2015

This forecast is for Tuesday, June 2, 2015:

If the trigger temperature of 81.2 F/27.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 1303 ft/min (6.6 m/s)
   Maximum height of thermals.................. 18787 ft MSL (13958 ft AGL)

Forecast maximum temperature................... 91.0 F/33.2 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 14781 ft MSL (9951 ft AGL)
Thermal soaring outlook for Wednesday 06/03.... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:49:55 / 20:34:10 MDT
Total possible sunshine........... 14 hr 44 min 14 sec (884 min 14 sec)
Altitude of sun at 13:12:13 MDT... 73.08 degrees

Upper air data from rawinsonde observation taken on 06/02/2015 at 0600 MDT

Freezing level.................. 14656 ft MSL (9827 ft AGL)
Convective condensation level... 20558 ft MSL (15729 ft AGL)
Lifted condensation level....... 19999 ft MSL (15170 ft AGL)
Lifted index.................... +1.0
K index......................... +9.7

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  -61.5 -78.7   295   19   10   3.9   2.2   94.1 201.4    35.3      M    M
 45000  -60.7 -77.3   285   30   15   9.5   5.2   70.9 159.6    23.5      M    M
 40000  -56.6 -69.9   270   51   26  -4.1  -2.3   53.5 128.3    13.7      M    M
 38000  -54.3 -65.7   260   50   26   8.7   4.8   48.2 118.7    10.5      M    M
 36000  -50.6 -59.1   260   48   25   9.3   5.1   45.1 113.1     8.6      M    M
 34000  -45.0 -49.0   260   46   24   9.4   5.1   44.7 112.5     8.6      M    M
 32000  -39.4 -38.9   260   45   23   9.2   5.1   44.4 112.0     8.6      M    M
 30000  -34.4 -29.9   265   45   23   8.2   4.5   43.3 110.0     8.0      M    M
 29000  -31.7 -25.1   260   42   21   6.6   3.6   42.1 107.9     7.2      M    M
 28000  -29.7 -21.5   250   39   20   6.0   3.3   41.0 105.7     6.4      M    M
 27000  -28.7 -19.7   245   38   19   8.0   4.4   38.5 101.4     4.5      M    M
 26000  -26.0 -14.8   235   37   19   9.1   5.0   38.3 101.0     4.3      M    M
 25000  -23.3  -9.9   245   35   18   9.3   5.1   38.1 100.6     4.2      M    M
 24000  -20.7  -5.3   245   36   19   9.6   5.3   37.6  99.6     3.8      M    M
 23000  -17.9  -0.2   250   35   18   9.1   5.0   37.4  99.4     3.8      M    M
 22000  -15.7   3.7   250   34   18   6.9   3.8   36.5  97.7     3.1      M    M
 21000  -13.7   7.3   255   33   17   6.9   3.8   35.6  96.0     2.3      M    M
 20000  -11.6  11.1   240   32   16   6.9   3.8   34.5  94.1     1.5      M    M
 19500  -10.6  12.9   235   34   17   7.1   3.9   34.0  93.2     1.0      M    M
 19000   -9.7  14.5   235   37   19   4.4   2.4   33.3  92.0     0.5      M    M
 18500   -9.0  15.8   230   37   19   4.4   2.4   32.4  90.3    -0.4   1289  6.5
 18000   -8.4  16.9   225   35   18   4.6   2.5   31.5  88.7    -1.2   1255  6.4
 17500   -7.6  18.3   225   34   17   8.6   4.7   30.9  87.5    -1.8   1216  6.2
 17000   -6.2  20.8   220   33   17   9.3   5.1   30.8  87.4    -1.9   1159  5.9
 16500   -4.8  23.4   220   31   16   9.5   5.2   30.7  87.3    -2.0   1102  5.6
 16000   -3.5  25.7   215   30   16   7.9   4.3   30.6  87.0    -2.1   1049  5.3
 15500   -1.8  28.8   215   29   15   8.2   4.5   30.1  86.2    -2.6    975  5.0
 15000   -0.6  30.9   215   28   14   8.3   4.5   29.9  85.8    -2.9    925  4.7
 14500    0.6  33.1   215   27   14   8.3   4.5   29.6  85.4    -3.2    874  4.4
 14000    1.9  35.4   215   26   13   8.3   4.5   29.4  85.0    -3.4    822  4.2
 13500    3.1  37.6   225   24   12   8.3   4.5   29.1  84.5    -3.7    771  3.9
 13000    4.3  39.7   230   23   12   8.3   4.5   28.9  84.0    -4.0    719  3.7
 12500    5.5  41.9   240   22   11   8.3   4.5   28.7  83.6    -4.2    668  3.4
 12000    6.8  44.2   245   22   11   8.2   4.5   28.4  83.2    -4.4    616  3.1
 11500    8.0  46.4   250   21   11   9.3   5.1   28.2  82.8    -4.7    563  2.9
 11000    9.4  48.9   250   20   10   9.4   5.2   28.2  82.7    -4.8    507  2.6
 10500   10.8  51.4   255   19   10   9.4   5.2   28.1  82.6    -4.9    451  2.3
 10250   11.5  52.7   255   19   10   9.3   5.1   28.1  82.6    -4.9    423  2.2
 10000   12.2  54.0   255   19   10   9.1   5.0   28.1  82.5    -5.0    396  2.0
  9750   12.8  55.0   260   20   10   9.2   5.0   28.0  82.4    -5.0    368  1.9
  9500   13.5  56.3   260   20   10   9.2   5.0   28.0  82.4    -5.1    340  1.7
  9250   14.2  57.6   265   21   11   9.2   5.0   27.9  82.3    -5.1    312  1.6
  9000   14.9  58.8   265   21   11   9.2   5.0   27.9  82.2    -5.2    284  1.4
  8750   15.6  60.1   265   21   11   9.0   5.0   27.8  82.1    -5.3    257  1.3
  8500   16.2  61.2   265   21   11   9.7   5.3   27.8  82.0    -5.3    229  1.2
  8250   16.9  62.4   260   21   11   7.3   4.0   27.8  82.0    -5.4    201  1.0
  8000   17.3  63.1   260   21   11   2.4   1.3   27.4  81.2    -5.8    184  0.9
  7750   17.4  63.3   260   18    9   1.5   0.8   26.7  80.1    -6.4    173  0.9
  7500   17.5  63.5   255   15    8   0.6   0.3   26.1  78.9    -7.1    162  0.8
  7250   17.6  63.7   255   12    6   5.8   3.2   25.5  77.9    -7.7    151  0.8
  7000   18.4  65.1   250    9    5  10.9   6.0   25.5  77.9    -7.7    121  0.6
  6750   19.1  66.4   245    7    4   9.5   5.2   25.5  77.9    -7.7     92  0.5
  6500   19.8  67.6   235    6    3  10.0   5.5   25.5  77.9    -7.7     63  0.3
  6250   20.5  68.9   220    4    2   9.6   5.3   25.5  77.9    -7.7     34  0.2
  6000   21.3  70.3   190    3    2  10.7   5.8   25.5  77.9    -7.7      4  0.0
  5750   22.0  71.6   150    3    1   6.8   3.7   25.5  77.9    -7.8      M    M
  5500   22.0  71.6   120    3    2  -7.1  -3.9   24.8  76.7    -8.5      M    M
  5250   20.9  69.6   100    5    2 -17.8  -9.8   23.1  73.5   -10.4      M    M
  5000   19.5  67.1   090    6    3 -17.5  -9.6   20.9  69.7   -12.6     29  0.1

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

           06/02/2015 at 0900 MDT          |       06/02/2015 at 1200 MDT
                                           |
K index... -1.9  LI... +278.6              | K index... -1.2  LI... +277.6
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.3
                                           |
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 -61.8 -79.2  275  19 10   0.8   0.4 | -62.5 -80.5  260  17  9   0.7   0.4
 45000 -60.1 -76.2  275  31 16   2.6   1.4 | -60.9 -77.6  260  29 15   2.7   1.5
 40000 -55.8 -68.4  275  44 23   5.2   2.8 | -56.5 -69.7  270  42 22   6.4   3.5
 38000 -52.5 -62.5  265  41 21   5.6   3.1 | -52.5 -62.5  260  40 21   6.6   3.6
 36000 -49.2 -56.6  255  39 20   5.6   3.1 | -48.6 -55.5  250  39 20   6.6   3.6
 34000 -44.4 -47.9  255  37 19   9.1   5.0 | -43.7 -46.7  250  39 20   8.9   4.9
 32000 -38.9 -38.0  255  35 18   9.1   5.0 | -38.4 -37.1  255  40 20   8.9   4.9
 30000 -34.1 -29.4  260  34 18   7.6   4.2 | -33.7 -28.7  255  39 20   7.1   3.9
 29000 -31.8 -25.2  260  34 18   7.6   4.2 | -31.6 -24.9  255  38 20   7.1   3.9
 28000 -28.9 -20.0  265  34 17   7.5   4.1 | -28.9 -20.0  260  37 19   7.0   3.8
 27000 -26.8 -16.2  260  35 18   6.9   3.8 | -26.9 -16.4  260  36 19   6.6   3.6
 26000 -24.8 -12.6  260  36 18   6.9   3.8 | -24.9 -12.8  260  36 18   6.6   3.6
 25000 -22.7  -8.9  260  37 19   6.9   3.8 | -23.0  -9.4  260  35 18   6.5   3.6
 24000 -20.5  -4.9  255  37 19   7.6   4.2 | -20.8  -5.4  260  35 18   7.6   4.2
 23000 -18.2  -0.8  255  36 18   7.6   4.2 | -18.5  -1.3  260  35 18   7.6   4.2
 22000 -16.0   3.2  255  35 18   7.6   4.2 | -16.2   2.8  260  35 18   7.5   4.1
 21000 -13.8   7.2  255  34 17   7.2   3.9 | -13.7   7.3  260  35 18   8.5   4.7
 20000 -11.6  11.1  250  33 17   7.2   3.9 | -11.2  11.8  260  34 17   8.5   4.7
 19500 -10.5  13.1  250  33 17   7.2   3.9 |  -9.9  14.2  260  33 17   8.5   4.7
 19000  -9.5  14.9  245  33 17   6.6   3.6 |  -8.6  16.5  260  33 17   8.2   4.5
 18500  -8.5  16.7  245  34 17   6.3   3.5 |  -7.4  18.7  260  33 17   8.0   4.4
 18000  -7.6  18.3  240  34 18   6.3   3.4 |  -6.2  20.8  260  32 17   8.1   4.4
 17500  -6.7  19.9  240  35 18   6.6   3.6 |  -5.2  22.6  255  32 17   6.3   3.4
 17000  -5.7  21.7  235  35 18   6.6   3.6 |  -4.2  24.4  255  33 17   6.4   3.5
 16500  -4.7  23.5  235  36 18   7.2   4.0 |  -3.3  26.1  250  33 17   5.6   3.1
 16000  -3.6  25.5  230  35 18   7.5   4.1 |  -2.5  27.5  250  34 17   5.3   2.9
 15500  -2.5  27.5  230  35 18   7.5   4.1 |  -1.7  28.9  245  35 18   5.2   2.9
 15000  -1.4  29.5  230  35 18   7.3   4.0 |  -1.0  30.2  245  34 18   5.2   2.9
 14500  -0.3  31.5  230  34 18   7.3   4.0 |  -0.2  31.6  240  34 17   5.4   3.0
 14000   0.8  33.4  225  33 17   6.9   3.8 |   0.5  32.9  240  32 16   5.1   2.8
 13500   2.3  36.1  225  31 16   6.7   3.7 |   1.6  34.9  235  28 14   6.0   3.3
 13000   3.2  37.8  225  28 14   6.1   3.4 |   2.5  36.5  230  24 12   7.4   4.1
 12500   4.1  39.4  225  25 13   6.3   3.5 |   3.6  38.5  225  21 11   7.7   4.2
 12000   5.1  41.2  225  23 12   7.5   4.1 |   4.8  40.6  225  18  9   8.9   4.9
 11500   6.2  43.2  230  22 11   7.6   4.2 |   6.1  43.0  220  16  8   8.8   4.8
 11000   7.4  45.3  235  20 10   8.2   4.5 |   7.4  45.3  220  15  8   7.9   4.3
 10500   8.6  47.5  240  18  9   5.1   2.8 |   8.6  47.5  220  13  7   5.1   2.8
 10250   8.8  47.8  240  18  9   6.3   3.5 |   8.9  48.0  220  12  6   5.9   3.2
 10000   9.6  49.3  240  17  9  11.3   6.2 |   9.5  49.1  220  11  6  10.3   5.6
  9750  10.3  50.5  240  16  8  10.2   5.6 |  10.2  50.4  220  10  5   9.2   5.1
  9500  11.1  52.0  245  15  8   9.5   5.2 |  10.9  51.6  220   9  5   9.0   4.9
  9250  11.7  53.1  245  15  8   6.9   3.8 |  11.5  52.7  220   8  4   8.4   4.6
  9000  12.2  54.0  240  14  7   6.9   3.8 |  12.2  54.0  220   7  4   9.2   5.0
  8750  12.7  54.9  240  13  6   7.9   4.3 |  12.9  55.2  220   7  4   9.5   5.2
  8500  13.3  55.9  235  12  6   7.1   3.9 |  13.6  56.5  220   6  3   9.6   5.3
  8250  13.8  56.8  230  10  5   6.1   3.3 |  14.3  57.7  225   6  3   9.9   5.4
  8000  14.2  57.6  225   9  5   5.5   3.0 |  15.0  59.0  225   6  3  10.0   5.5
  7750  14.6  58.3  220   8  4   5.0   2.7 |  15.8  60.4  225   6  3  10.0   5.5
  7500  15.0  59.0  210   7  3   5.4   3.0 |  16.5  61.7  225   6  3  10.1   5.5
  7250  15.4  59.7  205   6  3   5.8   3.2 |  17.3  63.1  225   6  3  10.2   5.6
  7000  15.8  60.4  195   6  3   5.8   3.2 |  18.0  64.4  230   6  3   9.9   5.4
  6750  16.2  61.2  190   6  3   6.0   3.3 |  18.7  65.7  230   6  3   9.8   5.4
  6500  16.6  61.9  180   7  3   5.9   3.2 |  19.5  67.1  230   6  3  10.7   5.9
  6250  17.0  62.6  180   6  3   6.2   3.4 |  20.3  68.5  230   5  3  11.7   6.4
  6000  17.4  63.3  175   6  3   5.2   2.9 |  21.2  70.2  230   5  3   9.7   5.3
  5750  17.7  63.9  170   6  3   7.2   4.0 |  21.9  71.4  235   5  3  11.3   6.2
  5500  18.4  65.1  170   6  3  10.8   6.0 |  22.9  73.2  235   5  3  15.7   8.6
  5250  19.1  66.4  170   6  3   9.1   5.0 |  24.0  75.2  235   5  3  14.0   7.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           06/02/2015 at 1500 MDT          |       06/02/2015 at 1800 MDT
                                           |
K index... +10.1  LI... +276.7             | K index... +15.4  LI... +275.8
CAPE... 0.0  CIN... -0.5                   | 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 -62.2 -80.0  260  24 12   1.0   0.6 | -61.9 -79.4  265  24 13   1.3   0.7
 45000 -60.2 -76.4  260  38 20   2.6   1.4 | -59.6 -75.3  265  40 21   2.2   1.2
 40000 -55.9 -68.6  260  40 21   6.3   3.5 | -55.9 -68.6  250  45 23   5.9   3.2
 38000 -52.1 -61.8  260  42 22   6.4   3.5 | -52.2 -62.0  255  47 24   6.2   3.4
 36000 -48.2 -54.8  255  43 22   6.5   3.5 | -48.5 -55.3  255  49 25   6.2   3.4
 34000 -43.7 -46.7  255  43 22   8.1   4.4 | -44.3 -47.7  260  50 26   7.5   4.1
 32000 -38.8 -37.8  255  43 22   8.1   4.4 | -39.7 -39.5  260  51 26   7.5   4.1
 30000 -34.2 -29.6  255  43 22   7.6   4.2 | -35.1 -31.2  260  51 26   7.8   4.3
 29000 -31.3 -24.3  255  43 22   7.6   4.2 | -32.8 -27.0  260  50 26   7.8   4.3
 28000 -29.1 -20.4  260  43 22   7.4   4.1 | -29.8 -21.6  260  50 26   7.8   4.3
 27000 -26.9 -16.4  260  42 22   7.0   3.9 | -27.5 -17.5  260  47 24   7.7   4.2
 26000 -24.8 -12.6  260  41 21   7.0   3.9 | -25.2 -13.4  260  44 23   7.7   4.2
 25000 -22.7  -8.9  260  40 20   7.0   3.9 | -22.9  -9.2  260  41 21   7.8   4.3
 24000 -20.6  -5.1  260  39 20   7.2   3.9 | -20.7  -5.3  255  39 20   7.3   4.0
 23000 -18.5  -1.3  260  38 20   7.2   3.9 | -18.5  -1.3  255  36 19   7.3   4.0
 22000 -16.3   2.7  260  38 19   7.0   3.8 | -16.3   2.7  250  34 17   7.3   4.0
 21000 -13.9   7.0  260  36 18   8.6   4.7 | -14.0   6.8  255  32 16   7.6   4.2
 20000 -11.3  11.7  260  33 17   8.6   4.7 | -11.7  10.9  255  30 16   7.6   4.2
 19500 -10.0  14.0  260  32 16   8.6   4.7 | -10.6  12.9  255  30 15   7.6   4.2
 19000  -8.8  16.2  260  31 16   8.0   4.4 |  -9.5  14.9  255  29 15   7.6   4.2
 18500  -7.6  18.3  260  30 15   7.8   4.3 |  -8.3  17.1  255  28 14   7.6   4.2
 18000  -6.4  20.5  260  29 15   7.8   4.3 |  -7.2  19.0  255  27 14   7.6   4.2
 17500  -5.3  22.5  260  29 15   7.0   3.8 |  -6.1  21.0  255  26 13   7.0   3.8
 17000  -4.3  24.3  260  28 15   7.1   3.9 |  -5.1  22.8  250  26 13   7.2   3.9
 16500  -3.2  26.2  260  28 15   5.9   3.3 |  -4.1  24.6  250  26 13   8.1   4.4
 16000  -2.5  27.5  255  28 15   5.6   3.1 |  -2.9  26.8  245  24 13   8.5   4.7
 15500  -1.7  28.9  250  28 15   5.8   3.2 |  -1.8  28.8  240  23 12   8.8   4.8
 15000  -0.8  30.6  245  27 14   6.3   3.4 |  -0.5  31.1  240  22 11   8.9   4.9
 14500  -0.0  32.0  240  26 13   6.4   3.5 |   0.8  33.4  235  20 10   8.9   4.9
 14000   1.7  35.1  235  23 12   8.7   4.8 |   2.1  35.8  230  18  9   8.4   4.6
 13500   3.0  37.4  230  21 11   8.7   4.8 |   4.0  39.2  225  16  8   8.5   4.7
 13000   4.2  39.6  225  19 10   8.5   4.6 |   5.3  41.5  225  14  7   8.6   4.7
 12500   5.5  41.9  220  18  9   8.4   4.6 |   6.6  43.9  220  13  7   8.5   4.7
 12000   6.7  44.1  215  16  8   7.6   4.2 |   7.8  46.0  215  12  6   8.1   4.4
 11500   7.8  46.0  215  14  7   7.6   4.2 |   9.0  48.2  210  11  6   8.0   4.4
 11000   8.8  47.8  215  12  6   6.5   3.6 |  10.1  50.2  210  10  5   6.6   3.6
 10500   9.8  49.6  215  10  5   9.5   5.2 |  11.0  51.8  205   9  4   9.0   4.9
 10250  10.6  51.1  215   9  5   9.9   5.4 |  11.8  53.2  205   8  4   9.7   5.3
 10000  11.2  52.2  215   8  4   6.3   3.4 |  12.4  54.3  200   7  4   6.9   3.8
  9750  11.7  53.1  220   6  3   7.3   4.0 |  12.9  55.2  200   6  3   7.8   4.3
  9500  12.2  54.0  230   5  3   6.9   3.8 |  13.5  56.3  200   6  3   7.0   3.9
  9250  12.7  54.9  240   4  2   8.3   4.6 |  14.0  57.2  195   5  2   6.1   3.4
  9000  13.4  56.1  240   4  2  10.0   5.5 |  14.5  58.1  195   4  2   6.5   3.5
  8750  14.2  57.6  245   4  2  10.0   5.5 |  14.9  58.8  195   3  1   6.6   3.6
  8500  14.9  58.8  250   4  2  10.1   5.5 |  15.4  59.7  200   2  1   7.3   4.0
  8250  15.7  60.3  255   4  2  10.1   5.5 |  16.0  60.8  210   1  1   9.3   5.1
  8000  16.4  61.5  255   4  2   9.9   5.4 |  16.7  62.1  225   1  1   9.4   5.2
  7750  17.2  63.0  255   4  2   9.6   5.3 |  17.4  63.3  240   1  1   8.5   4.7
  7500  17.9  64.2  255   4  2   9.9   5.4 |  18.1  64.6  255   1  1   9.5   5.2
  7250  18.6  65.5  260   4  2  10.3   5.6 |  18.8  65.8  260   1  1  10.8   5.9
  7000  19.4  66.9  260   4  2  10.1   5.6 |  19.6  67.3  265   1  1  10.2   5.6
  6750  20.1  68.2  260   4  2  10.0   5.5 |  20.3  68.5  265   1  1   9.3   5.1
  6500  20.9  69.6  265   5  2  10.6   5.8 |  21.0  69.8  270   2  1  10.1   5.5
  6250  21.7  71.1  265   5  2  11.4   6.3 |  21.8  71.2  270   2  1  11.0   6.0
  6000  22.6  72.7  265   5  2  10.0   5.5 |  22.6  72.7  270   2  1  10.2   5.6
  5750  23.3  73.9  265   4  2  11.1   6.1 |  23.4  74.1  270   2  1   9.5   5.2
  5500  24.3  75.7  265   4  2  15.2   8.3 |  24.1  75.4  270   2  1  10.0   5.5
  5250  25.4  77.7  270   5  2  15.6   8.6 |  24.8  76.6  270   2  1  10.6   5.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  Note that some elevations in numerical weather prediction models
differ from actual station elevations, which can lead to data which appear
to be below ground.  Erroneous data such as these should not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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