Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 011248
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0648 MDT Monday, June 1, 2015

This forecast is for Monday, June 1, 2015:

If the trigger temperature of 80.7 F/27.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1236 ft/min (6.3 m/s)
   Maximum height of thermals.................. 19866 ft MSL (15027 ft AGL)

Forecast maximum temperature................... 90.0 F/32.7 C
Time of trigger temperature.................... 1045 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................. 12916 ft MSL (8077 ft AGL)
Thermal soaring outlook for Tuesday 06/02...... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:50:19 / 20:33:28 MDT
Total possible sunshine........... 14 hr 43 min 9 sec (883 min 9 sec)
Altitude of sun at 13:12:04 MDT... 72.95 degrees

Upper air data from rawinsonde observation taken on 06/01/2015 at 0600 MDT

Freezing level.................. 14733 ft MSL (9894 ft AGL)
Convective condensation level... 16146 ft MSL (11307 ft AGL)
Lifted condensation level....... 17073 ft MSL (12234 ft AGL)
Lifted index.................... -3.4
K index......................... +23.3

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  -67.4 -89.3   295   33   17  -0.6  -0.3   85.6 186.1    30.6      M    M
 45000  -64.8 -84.6   270   24   12  -1.9  -1.0   64.2 147.5    19.7      M    M
 40000  -58.4 -73.1   250   23   12   7.3   4.0   51.1 124.0    12.5      M    M
 38000  -54.1 -65.4   260   25   13   7.2   4.0   48.8 119.8    11.3      M    M
 36000  -49.8 -57.6   260   27   14   7.0   3.8   46.7 116.0    10.1      M    M
 34000  -44.5 -48.1   245   22   11   8.8   4.8   45.8 114.4     9.7      M    M
 32000  -40.1 -40.2   270   23   12  11.4   6.3   42.9 109.3     7.9      M    M
 30000  -34.1 -29.4   265   20   10   9.9   5.4   43.2 109.7     8.3      M    M
 29000  -31.2 -24.2   250   17    9   8.3   4.6   43.1 109.7     8.3      M    M
 28000  -28.9 -20.0   245   20   10   7.8   4.3   42.3 108.1     7.8      M    M
 27000  -27.0 -16.6   245   23   12   5.7   3.1   40.9 105.6     6.8      M    M
 26000  -25.3 -13.5   240   26   13   7.4   4.1   39.4 103.0     5.7      M    M
 25000  -23.8 -10.8   240   29   15   7.4   4.1   37.8 100.0     4.3      M    M
 24000  -21.8  -7.2   245   25   13   7.9   4.4   36.7  98.1     3.5      M    M
 23000  -19.4  -2.9   250   23   12   7.8   4.3   36.0  96.8     2.9      M    M
 22000  -17.2   1.0   255   22   11   5.5   3.0   35.1  95.1     2.2      M    M
 21000  -15.7   3.7   235   19   10   6.5   3.6   33.5  92.3     0.8      M    M
 20000  -13.4   7.9   250   16    8   7.3   4.0   32.8  91.1     0.2      M    M
 19500  -12.4   9.7   255   17    9   7.8   4.3   32.4  90.3    -0.2   1411  7.2
 19000  -11.5  11.3   260   19   10   6.4   3.5   31.7  89.1    -0.8   1370  7.0
 18500  -10.1  13.8   265   20   10   9.4   5.2   31.6  88.9    -0.9   1314  6.7
 18000   -8.7  16.3   265   21   11   9.5   5.2   31.6  88.9    -0.9   1256  6.4
 17500   -6.7  19.9   260   20   10   7.9   4.3   31.4  88.6    -1.1   1173  6.0
 17000   -5.5  22.1   260   18    9   7.9   4.3   31.1  88.0    -1.5   1125  5.7
 16500   -4.4  24.1   240   13    7   8.4   4.6   30.8  87.5    -1.8   1076  5.5
 16000   -3.1  26.4   220   11    6   8.7   4.8   30.7  87.2    -1.9   1022  5.2
 15500   -1.8  28.8   220   10    5   8.8   4.8   30.5  86.9    -2.1    968  4.9
 15000   -0.5  31.1   220    9    5   8.8   4.8   30.4  86.7    -2.2    915  4.6
 14500    0.8  33.4   225   11    6   8.8   4.8   30.2  86.4    -2.4    861  4.4
 14000    2.1  35.8   230   13    7   8.8   4.8   30.1  86.1    -2.6    807  4.1
 13500    3.4  38.1   220   15    8   8.8   4.8   29.9  85.7    -2.8    753  3.8
 13000    4.7  40.5   215   17    9   8.7   4.8   29.7  85.4    -3.0    700  3.6
 12500    6.0  42.8   215   19   10   9.3   5.1   29.6  85.2    -3.1    645  3.3
 12000    7.4  45.3   210   21   11   9.4   5.2   29.5  85.1    -3.2    589  3.0
 11500    8.8  47.8   210   19   10   9.4   5.2   29.5  85.0    -3.3    532  2.7
 11000   10.2  50.4   215   17    9   9.5   5.2   29.4  85.0    -3.4    476  2.4
 10500   11.6  52.9   210   17    9  10.9   6.0   29.3  84.8    -3.5    419  2.1
 10250   12.4  54.3   205   17    9   8.9   4.9   29.5  85.0    -3.3    386  2.0
 10000   12.9  55.2   200   17    9   5.7   3.1   29.2  84.5    -3.6    365  1.9
  9750   13.4  56.1   190   17    9   6.6   3.6   28.9  84.0    -3.9    344  1.7
  9500   13.8  56.8   185   17    9   6.4   3.5   28.7  83.6    -4.2    323  1.6
  9250   14.3  57.7   175   18    9   6.4   3.5   28.4  83.1    -4.5    302  1.5
  9000   14.7  58.5   170   19   10   6.3   3.5   28.1  82.6    -4.7    281  1.4
  8750   15.2  59.4   170   19   10   6.3   3.5   27.9  82.2    -5.0    260  1.3
  8500   15.6  60.1   170   19   10   6.5   3.5   27.6  81.7    -5.3    239  1.2
  8250   16.0  60.8   165   18    9   3.0   1.6   27.3  81.1    -5.7    220  1.1
  8000   16.1  61.0   165   18    9   0.3   0.2   26.6  79.8    -6.4    211  1.1
  7750   16.1  61.0   165   19   10   0.9   0.5   25.9  78.6    -7.1    202  1.0
  7500   16.2  61.2   165   19   10   1.3   0.7   25.2  77.4    -7.8    193  1.0
  7250   16.4  61.5   170   20   10   5.3   2.9   24.7  76.4    -8.3    179  0.9
  7000   16.9  62.4   170   21   11   7.8   4.3   24.5  76.1    -8.5    156  0.8
  6750   17.4  63.3   170   22   11   6.6   3.6   24.3  75.7    -8.8    133  0.7
  6500   17.9  64.2   165   22   11   8.8   4.8   24.1  75.4    -9.0    110  0.6
  6250   18.5  65.3   165   23   12   1.2   0.6   23.9  75.0    -9.2     87  0.4
  6000   18.1  64.6   160   24   12  -5.7  -3.1   22.8  73.1   -10.3     90  0.5
  5750   18.0  64.4   155   21   11   2.2   1.2   21.9  71.5   -11.2     87  0.4
  5500   18.3  64.9   150   18    9   5.6   3.1   21.5  70.8   -11.6     70  0.4
  5250   18.7  65.7   145   15    8   4.2   2.3   21.2  70.1   -12.1     52  0.3
  5000   19.0  66.2   130   12    6   6.4   3.5   20.8  69.4   -12.5     35  0.2

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

           06/01/2015 at 0900 MDT          |       06/01/2015 at 1200 MDT
                                           |
K index... +24.6  LI... +272.0             | K index... +27.4  LI... +269.6
CAPE... +123.7  CIN... -219.3              | CAPE... +672.0  CIN... -34.3
                                           |
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 -63.7 -82.7  280  17  9  -0.1  -0.1 | -63.4 -82.1  270  14  7   0.6   0.3
 45000 -63.0 -81.4  265  27 14   2.9   1.6 | -62.0 -79.6  255  21 11   2.2   1.2
 40000 -58.5 -73.3  255  32 17   6.7   3.7 | -58.5 -73.3  245  32 16   6.0   3.3
 38000 -53.8 -64.8  255  30 15   7.8   4.3 | -54.1 -65.4  240  31 16   7.4   4.1
 36000 -49.1 -56.4  250  28 14   7.8   4.3 | -49.6 -57.3  240  30 16   7.4   4.1
 34000 -44.3 -47.7  250  25 13   8.0   4.4 | -44.1 -47.4  240  29 15   8.3   4.6
 32000 -38.9 -38.0  250  22 11   8.0   4.4 | -39.2 -38.6  240  28 14   8.3   4.6
 30000 -34.0 -29.2  245  19 10   8.2   4.5 | -34.2 -29.6  235  26 13   8.2   4.5
 29000 -31.5 -24.7  240  18  9   8.2   4.5 | -31.8 -25.2  235  24 13   8.2   4.5
 28000 -29.1 -20.4  235  17  9   7.7   4.2 | -29.3 -20.7  230  23 12   7.7   4.2
 27000 -27.2 -17.0  245  17  9   6.0   3.3 | -27.5 -17.5  235  23 12   5.9   3.3
 26000 -25.4 -13.7  250  17  9   6.0   3.3 | -25.7 -14.3  240  22 12   6.0   3.3
 25000 -23.6 -10.5  255  18  9   6.0   3.3 | -23.9 -11.0  245  22 11   5.9   3.2
 24000 -21.8  -7.2  255  18  9   6.1   3.3 | -21.9  -7.4  245  21 11   7.2   4.0
 23000 -20.0  -4.0  255  18  9   6.2   3.4 | -19.7  -3.5  245  20 10   7.3   4.0
 22000 -18.2  -0.8  250  19 10   6.1   3.4 | -17.5   0.5  245  19 10   7.3   4.0
 21000 -15.8   3.6  250  19 10   8.7   4.8 | -15.3   4.5  240  20 10   7.7   4.3
 20000 -13.3   8.1  250  20 10   8.7   4.8 | -13.0   8.6  235  21 11   7.8   4.3
 19500 -12.0  10.4  250  20 10   8.8   4.8 | -11.9  10.6  230  22 11   7.8   4.3
 19000 -10.8  12.6  250  20 10   8.3   4.5 | -10.7  12.7  230  23 12   8.6   4.7
 18500  -9.6  14.7  250  21 11   8.2   4.5 |  -9.4  15.1  230  24 12   8.8   4.8
 18000  -8.4  16.9  250  22 11   8.2   4.5 |  -8.2  17.2  230  25 13   8.8   4.8
 17500  -7.2  19.0  250  23 12   8.6   4.7 |  -6.9  19.6  230  25 13   8.6   4.7
 17000  -5.9  21.4  245  23 12   8.6   4.7 |  -5.7  21.7  230  25 13   8.6   4.7
 16500  -4.6  23.7  245  23 12   8.7   4.8 |  -4.4  24.1  230  24 13   9.1   5.0
 16000  -3.3  26.1  245  23 12   8.8   4.8 |  -3.1  26.4  230  23 12   9.2   5.0
 15500  -1.3  29.7  240  21 11   9.4   5.1 |  -1.0  30.2  230  22 11   8.9   4.9
 15000   0.1  32.2  240  20 10   9.3   5.1 |   0.3  32.5  230  20 10   8.9   4.9
 14500   1.4  34.5  240  19 10   9.3   5.1 |   1.6  34.9  230  19 10   8.7   4.8
 14000   2.8  37.0  240  18  9   9.3   5.1 |   2.9  37.2  230  18  9   8.7   4.8
 13500   4.2  39.6  235  17  9   9.3   5.1 |   4.2  39.6  230  17  9   8.9   4.9
 13000   5.6  42.1  235  16  8   9.4   5.1 |   5.5  41.9  225  16  8   9.1   5.0
 12500   7.0  44.6  235  15  8   9.3   5.1 |   6.9  44.4  225  15  8   9.1   5.0
 12000   8.4  47.1  235  15  8   9.2   5.1 |   8.2  46.8  225  15  8   9.2   5.1
 11500   9.7  49.5  235  14  7   9.2   5.0 |   9.6  49.3  230  14  7   9.1   5.0
 11000  11.1  52.0  235  13  7   8.7   4.8 |  10.9  51.6  230  14  7   8.5   4.7
 10500  12.4  54.3  235  13  7   5.6   3.0 |  12.2  54.0  230  13  7   5.5   3.0
 10250  12.7  54.9  235  12  6   6.1   3.3 |  12.4  54.3  225  13  7   6.2   3.4
 10000  13.4  56.1  230  12  6  10.7   5.9 |  13.1  55.6  230  12  6  10.7   5.8
  9750  14.1  57.4  230  12  6   9.7   5.3 |  13.9  57.0  230  12  6   9.9   5.4
  9500  14.8  58.6  230  12  6   9.0   4.9 |  14.6  58.3  230  11  6   8.5   4.6
  9250  15.4  59.7  225  12  6   7.2   4.0 |  15.1  59.2  225  11  5   6.8   3.7
  9000  15.9  60.6  225  12  6   7.2   4.0 |  15.6  60.1  225   9  5   7.9   4.3
  8750  16.5  61.7  220  13  6   7.6   4.2 |  16.2  61.2  225   8  4   8.0   4.4
  8500  17.0  62.6  215  13  7   6.8   3.7 |  16.8  62.2  225   7  4   8.2   4.5
  8250  17.4  63.3  210  13  7   6.0   3.3 |  17.4  63.3  220   7  3   8.5   4.7
  8000  17.9  64.2  205  13  7   5.1   2.8 |  18.0  64.4  220   6  3   9.1   5.0
  7750  18.2  64.8  195  13  7   4.5   2.5 |  18.7  65.7  220   6  3   9.5   5.2
  7500  18.5  65.3  185  13  7   3.4   1.9 |  19.3  66.7  220   6  3   9.7   5.3
  7250  18.7  65.7  180  14  7   2.2   1.2 |  20.1  68.2  220   6  3  10.1   5.5
  7000  18.8  65.8  175  14  7   2.3   1.3 |  20.8  69.4  220   6  3  10.0   5.5
  6750  19.0  66.2  170  15  8   2.1   1.1 |  21.6  70.9  220   6  3  10.2   5.6
  6500  19.1  66.4  170  14  7   2.4   1.3 |  22.3  72.1  220   6  3  10.6   5.8
  6250  19.2  66.6  165  11  6   2.9   1.6 |  23.2  73.8  225   6  3  11.2   6.1
  6000  19.3  66.7  160   9  5   2.1   1.2 |  24.0  75.2  225   6  3   9.5   5.2
  5750  19.4  66.9  155   7  4   6.0   3.3 |  24.6  76.3  225   5  3  11.1   6.1
  5500  20.1  68.2  150   7  3  10.7   5.9 |  25.6  78.1  225   5  3  14.9   8.2
  5250  20.8  69.4  150   6  3   7.6   4.2 |  26.7  80.1  225   6  3  12.8   7.0
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           06/01/2015 at 1500 MDT          |       06/01/2015 at 1800 MDT
                                           |
K index... +30.4  LI... +271.5             | K index... +25.5  LI... +272.1
CAPE... +353.6  CIN... -10.5               | CAPE... +139.6  CIN... -45.6
                                           |
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 -62.8 -81.0  270  18  9   0.6   0.3 | -62.7 -80.9  280  21 11  -0.1  -0.0
 45000 -61.5 -78.7  250  23 12   2.1   1.1 | -62.1 -79.8  260  30 15   2.7   1.5
 40000 -57.8 -72.0  240  36 18   8.0   4.4 | -57.5 -71.5  260  34 18   7.5   4.1
 38000 -53.4 -64.1  235  35 18   7.4   4.0 | -53.3 -63.9  260  33 17   7.1   3.9
 36000 -48.9 -56.0  230  35 18   7.4   4.1 | -49.1 -56.4  260  33 17   7.1   3.9
 34000 -44.3 -47.7  230  33 17   8.0   4.4 | -44.5 -48.1  255  32 17   8.0   4.4
 32000 -39.5 -39.1  230  31 16   8.0   4.4 | -39.7 -39.5  250  32 16   8.0   4.4
 30000 -34.7 -30.5  230  30 15   8.0   4.4 | -34.7 -30.5  250  31 16   8.4   4.6
 29000 -32.3 -26.1  235  29 15   8.0   4.4 | -32.2 -26.0  250  31 16   8.4   4.6
 28000 -29.9 -21.8  240  29 15   8.1   4.5 | -29.7 -21.5  250  30 16   8.5   4.7
 27000 -27.1 -16.8  240  29 15   7.4   4.0 | -26.9 -16.4  250  30 15   7.4   4.0
 26000 -24.9 -12.8  240  28 15   7.4   4.0 | -24.7 -12.5  250  30 15   7.4   4.1
 25000 -22.7  -8.9  240  28 15   7.4   4.0 | -22.5  -8.5  250  29 15   7.5   4.1
 24000 -20.6  -5.1  240  28 15   7.3   4.0 | -20.5  -4.9  250  30 16   6.6   3.6
 23000 -18.5  -1.3  240  28 15   7.3   4.0 | -18.5  -1.3  245  32 16   6.6   3.6
 22000 -16.3   2.7  245  28 15   7.4   4.1 | -16.5   2.3  245  33 17   6.7   3.7
 21000 -14.0   6.8  240  28 14   8.0   4.4 | -14.3   6.3  245  32 17   8.0   4.4
 20000 -11.7  10.9  230  28 14   8.0   4.4 | -12.0  10.4  240  31 16   8.1   4.5
 19500 -10.5  13.1  230  28 14   8.1   4.4 | -10.9  12.4  240  31 16   8.2   4.5
 19000  -9.4  15.1  225  28 14   7.9   4.3 |  -9.7  14.5  240  30 15   8.6   4.7
 18500  -8.2  17.2  225  27 14   7.9   4.3 |  -8.4  16.9  235  28 14   8.6   4.7
 18000  -7.1  19.2  225  26 14   7.7   4.2 |  -7.2  19.0  235  27 14   8.7   4.8
 17500  -6.0  21.2  220  25 13   7.2   3.9 |  -6.0  21.2  235  25 13   8.6   4.7
 17000  -5.0  23.0  220  24 12   7.2   4.0 |  -4.7  23.5  230  24 12   8.6   4.7
 16500  -4.0  24.8  220  23 12   7.1   3.9 |  -3.4  25.9  230  23 12   9.1   5.0
 16000  -2.9  26.8  220  22 11   7.1   3.9 |  -2.1  28.2  230  22 11   9.1   5.0
 15500  -1.9  28.6  220  21 11   7.3   4.0 |  -0.7  30.7  225  22 11   9.4   5.1
 15000  -0.8  30.6  220  20 10   7.4   4.1 |   0.7  33.3  225  21 11   9.7   5.3
 14500   0.2  32.4  220  18  9   7.8   4.3 |   2.2  36.0  225  20 10   9.6   5.3
 14000   1.6  34.9  220  17  9   9.7   5.3 |   3.6  38.5  225  19 10   9.5   5.2
 13500   3.0  37.4  220  16  8   9.6   5.3 |   5.0  41.0  225  18  9   9.6   5.2
 13000   5.1  41.2  220  15  8   9.7   5.3 |   7.0  44.6  220  16  8   8.7   4.8
 12500   6.6  43.9  220  14  7   9.7   5.3 |   8.3  46.9  220  15  8   8.7   4.8
 12000   8.0  46.4  220  14  7   9.6   5.3 |   9.6  49.3  220  14  7   8.5   4.7
 11500   9.4  48.9  220  13  7   9.3   5.1 |  10.8  51.4  220  13  7   8.3   4.6
 11000  10.7  51.3  225  12  6   8.4   4.6 |  12.0  53.6  220  12  6   7.2   3.9
 10500  11.9  53.4  225  11  6  11.6   6.3 |  13.0  55.4  215  10  5   9.6   5.3
 10250  13.0  55.4  230  10  5  12.0   6.6 |  13.8  56.8  215  10  5  10.1   5.5
 10000  13.6  56.5  235  10  5   7.9   4.4 |  14.4  57.9  215   9  4   7.2   3.9
  9750  14.3  57.7  240   9  5   9.3   5.1 |  15.0  59.0  215   8  4   8.1   4.4
  9500  14.9  58.8  245   8  4   7.9   4.4 |  15.6  60.1  215   7  4   7.4   4.1
  9250  15.5  59.9  250   8  4   7.9   4.3 |  16.1  61.0  215   6  3   7.4   4.0
  9000  16.1  61.0  255   7  4   9.1   5.0 |  16.7  62.1  215   5  3   7.9   4.3
  8750  16.8  62.2  260   7  4   8.8   4.8 |  17.2  63.0  220   4  2   7.6   4.2
  8500  17.4  63.3  265   7  4   9.8   5.4 |  17.8  64.0  220   3  2   8.5   4.7
  8250  18.2  64.8  270   7  4  10.8   5.9 |  18.5  65.3  220   2  1  10.0   5.5
  8000  18.9  66.0  270   7  4   9.7   5.3 |  19.2  66.6  225   2  1   9.3   5.1
  7750  19.6  67.3  270   7  4   8.9   4.9 |  19.8  67.6  225   2  1   8.1   4.5
  7500  20.3  68.5  275   7  4   9.8   5.4 |  20.5  68.9  225   2  1   9.4   5.2
  7250  21.1  70.0  275   7  4  10.6   5.8 |  21.2  70.2  225   2  1  11.0   6.0
  7000  21.9  71.4  275   7  4  10.1   5.5 |  22.0  71.6  225   2  1  10.2   5.6
  6750  22.6  72.7  275   7  4   9.9   5.4 |  22.8  73.0  225   2  1   9.2   5.1
  6500  23.4  74.1  275   7  4  10.4   5.7 |  23.5  74.3  225   2  1  10.0   5.5
  6250  24.1  75.4  275   7  4  10.8   5.9 |  24.2  75.6  230   2  1  10.8   5.9
  6000  24.9  76.8  275   7  4  10.2   5.6 |  25.0  77.0  235   2  1   9.9   5.5
  5750  25.7  78.3  275   7  4  11.6   6.4 |  25.7  78.3  235   2  1   9.0   5.0
  5500  26.6  79.9  275   7  4  14.0   7.7 |  26.4  79.5  235   2  1   9.5   5.2
  5250  27.7  81.9  275   7  4  13.4   7.4 |  27.1  80.8  240   2  1  10.4   5.7
  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 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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