Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 020104
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1904 MDT Monday, June 1, 2015

This forecast is for Tuesday, June 2, 2015:

If the trigger temperature of 82.1 F/27.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1321 ft/min (6.7 m/s)
   Maximum height of thermals.................. 18804 ft MSL (13497 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 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................. 10749 ft MSL (5443 ft AGL)
Thermal soaring outlook for Wednesday 06/03.... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 22316 ft MSL (17009 ft AGL)
Wave soaring outlook for Wednesday 06/03....... Poor

Remarks... None

Sunrise/Sunset.................... 05:33:19 / 20:21:26 MDT
Total possible sunshine........... 14 hr 48 min 7 sec (888 min 7 sec)
Altitude of sun at 12:57:34 MDT... 72.42 degrees

Upper air data from numerical model forecast valid on 06/02/2015 at 0600 MDT

Freezing level.................. 15042 ft MSL (9735 ft AGL)
Convective condensation level... 18830 ft MSL (13523 ft AGL)
Lifted condensation level....... 18938 ft MSL (13632 ft AGL)
Lifted index.................... +0.7
K index......................... +11.3

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  -62.9 -81.2   310   16    8   1.1   0.6      M     M       M      M    M
 45000  -61.0 -77.8   295   20   11   1.7   0.9      M     M       M      M    M
 40000  -58.4 -73.1   275   27   14   4.8   2.6      M     M       M      M    M
 38000  -54.2 -65.6   265   28   14   7.0   3.8      M     M       M      M    M
 36000  -50.0 -58.0   255   30   15   7.0   3.8      M     M       M      M    M
 34000  -44.4 -47.9   250   31   16   8.9   4.9      M     M       M      M    M
 32000  -39.1 -38.4   250   32   16   8.9   4.9      M     M       M      M    M
 30000  -34.0 -29.2   245   28   14   8.2   4.5   41.2 106.2     7.7      M    M
 29000  -31.6 -24.9   245   25   13   8.2   4.5   40.6 105.1     7.3      M    M
 28000  -29.1 -20.4   240   22   11   8.2   4.5   40.2 104.3     7.0      M    M
 27000  -26.7 -16.1   250   22   11   8.3   4.5   39.5 103.1     6.6      M    M
 26000  -24.2 -11.6   255   22   11   8.3   4.5   38.9 102.0     6.2      M    M
 25000  -21.7  -7.1   265   22   11   8.3   4.6   38.4 101.2     5.9      M    M
 24000  -19.4  -2.9   270   23   12   7.0   3.8   37.6  99.6     5.2      M    M
 23000  -17.3   0.9   270   24   13   7.0   3.8   36.5  97.7     4.5      M    M
 22000  -15.2   4.6   275   25   13   7.1   3.9   35.6  96.1     3.7      M    M
 21000  -13.4   7.9   270   25   13   5.8   3.2   34.3  93.7     2.7      M    M
 20000  -11.7  10.9   265   23   12   5.9   3.2   32.9  91.2     1.5      M    M
 19500  -10.8  12.6   260   22   11   5.9   3.3   32.2  90.0     0.9      M    M
 19000   -9.9  14.2   260   21   11   6.3   3.5   31.6  88.9     0.3      M    M
 18500   -9.0  15.8   255   20   10   6.7   3.7   31.1  87.9    -0.2   1304  6.6
 18000   -7.5  18.5   245   17    9   7.8   4.3   30.3  86.6    -0.9   1239  6.3
 17500   -6.2  20.8   240   16    8   8.6   4.7   30.1  86.2    -1.2   1186  6.0
 17000   -5.0  23.0   235   14    7   8.7   4.8   30.0  85.9    -1.3   1133  5.8
 16500   -3.7  25.3   240   13    7   9.0   5.0   29.8  85.7    -1.5   1079  5.5
 16000   -2.3  27.9   245   12    6   9.0   5.0   29.7  85.4    -1.6   1024  5.2
 15500   -1.0  30.2   250   12    6   9.0   4.9   29.6  85.2    -1.8    969  4.9
 15000    0.3  32.5   250   11    6   9.0   5.0   29.4  85.0    -1.9    915  4.6
 14500    1.6  34.9   255   10    5   9.2   5.0   29.3  84.8    -2.1    860  4.4
 14000    3.0  37.4   260   11    6   9.3   5.1   29.2  84.6    -2.2    804  4.1
 13500    4.4  39.9   265   11    6   9.3   5.1   29.2  84.5    -2.2    747  3.8
 13000    5.8  42.4   270   12    6   9.3   5.1   29.1  84.4    -2.3    690  3.5
 12500    7.2  45.0   275   13    7   9.3   5.1   29.0  84.3    -2.4    633  3.2
 12000    8.6  47.5   280   12    6   8.9   4.9   28.9  84.0    -2.5    578  2.9
 11500    9.9  49.8   280   11    6   9.1   5.0   28.8  83.8    -2.7    523  2.7
 11000   11.2  52.2   285   11    6   8.1   4.5   28.6  83.5    -2.9    471  2.4
 10500   12.4  54.3   290   12    6  11.3   6.2   28.3  83.0    -3.1    419  2.1
 10250   13.4  56.1   290   13    7  11.9   6.5   28.6  83.5    -2.9    381  1.9
 10000   14.1  57.4   290   14    7   8.2   4.5   28.5  83.4    -2.9    354  1.8
  9750   14.7  58.5   290   15    7   9.1   5.0   28.5  83.2    -3.0    327  1.7
  9500   15.4  59.7   290   15    8   9.0   4.9   28.4  83.1    -3.1    300  1.5
  9250   16.0  60.8   290   16    8   7.7   4.2   28.3  83.0    -3.2    273  1.4
  9000   16.6  61.9   290   16    8   8.0   4.4   28.1  82.6    -3.4    249  1.3
  8750   17.3  63.1   290   17    9   9.4   5.2   28.1  82.5    -3.4    222  1.1
  8500   17.9  64.2   290   18    9   9.0   5.0   28.0  82.5    -3.5    194  1.0
  8250   18.6  65.5   290   18    9   9.3   5.1   28.0  82.4    -3.6    167  0.8
  8000   19.3  66.7   290   18    9   9.0   4.9   28.0  82.3    -3.7    139  0.7
  7750   19.9  67.8   290   17    9   8.6   4.7   27.9  82.2    -3.8    113  0.6
  7500   20.5  68.9   295   17    9   8.4   4.6   27.8  82.0    -3.9     87  0.4
  7250   21.1  70.0   295   16    8   8.2   4.5   27.7  81.8    -4.0     61  0.3
  7000   21.7  71.1   295   16    8   6.9   3.8   27.5  81.5    -4.2     37  0.2
  6750   22.2  72.0   295   15    8   8.0   4.4   27.3  81.1    -4.4     15  0.1
  6500   22.6  72.7   295   15    8  -3.3  -1.8   26.9  80.5    -4.8      M    M
  6250   21.5  70.7   285   14    7 -16.1  -8.8   25.3  77.5    -6.6     19  0.1
  6000   20.3  68.5   275   13    7 -13.2  -7.2   23.4  74.1    -8.5     48  0.2
  5750   19.0  66.2   265   13    6 -22.9 -12.6   21.5  70.7   -10.6     81  0.4
  5500   16.2  61.2   240   12    6 -46.4 -25.4   18.2  64.7   -14.2    159  0.8

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

           06/02/2015 at 0900 MDT          |       06/02/2015 at 1200 MDT
                                           |
K index... -0.3  LI... +275.0              | K index... -1.4  LI... +274.9
CAPE... 0.0  CIN... -0.4                   | CAPE... 0.0  CIN... -1.2
                                           |
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 -62.9 -81.2  320  13  7   1.3   0.7 | -62.1 -79.8  295  15  7   1.1   0.6
 45000 -60.8 -77.4  300  17  9   1.8   1.0 | -60.3 -76.5  285  22 11   1.9   1.0
 40000 -58.1 -72.6  290  36 19   4.5   2.5 | -57.1 -70.8  280  36 18   6.8   3.7
 38000 -53.9 -65.0  280  34 18   7.0   3.9 | -52.9 -63.2  275  35 18   7.1   3.9
 36000 -49.1 -56.4  270  33 17   7.1   3.9 | -48.6 -55.5  265  35 18   7.1   3.9
 34000 -44.3 -47.7  265  32 16   8.4   4.6 | -44.1 -47.4  260  33 17   7.8   4.3
 32000 -39.2 -38.6  255  30 16   8.4   4.6 | -39.4 -38.9  255  31 16   7.9   4.3
 30000 -34.5 -30.1  250  26 14   7.6   4.2 | -35.0 -31.0  250  28 14   7.1   3.9
 29000 -32.2 -26.0  240  24 12   7.6   4.2 | -32.3 -26.1  240  25 13   7.1   3.9
 28000 -30.0 -22.0  235  22 11   7.7   4.2 | -30.2 -22.4  230  24 12   7.5   4.1
 27000 -27.4 -17.3  240  21 11   8.7   4.8 | -27.7 -17.9  235  23 12   8.3   4.6
 26000 -24.8 -12.6  250  21 11   8.7   4.8 | -25.2 -13.4  240  21 11   8.3   4.6
 25000 -22.2  -8.0  255  21 11   8.7   4.8 | -22.7  -8.9  245  20 10   8.4   4.6
 24000 -19.8  -3.6  260  21 11   7.4   4.1 | -20.3  -4.5  250  19 10   7.8   4.3
 23000 -17.6   0.3  265  22 11   7.4   4.0 | -18.0  -0.4  255  20 10   7.8   4.3
 22000 -15.4   4.3  270  23 12   7.5   4.1 | -15.6   3.9  260  20 10   7.9   4.3
 21000 -13.4   7.9  270  23 12   6.2   3.4 | -13.4   7.9  255  20 10   7.2   3.9
 20000 -11.5  11.3  265  22 11   6.2   3.4 | -11.3  11.7  255  20 10   7.2   3.9
 19500 -10.6  12.9  260  21 11   6.2   3.4 | -10.2  13.6  255  20 10   7.2   3.9
 19000  -9.7  14.5  260  21 11   6.7   3.7 |  -9.1  15.6  255  20 10   7.7   4.2
 18500  -8.1  17.4  255  20 10   7.2   4.0 |  -7.9  17.8  255  20 10   7.9   4.3
 18000  -7.0  19.4  250  20 10   7.7   4.2 |  -6.8  19.8  255  20 10   7.9   4.3
 17500  -5.8  21.6  245  19 10   8.0   4.4 |  -5.6  21.9  260  20 11   8.1   4.4
 17000  -4.6  23.7  240  18  9   8.1   4.4 |  -4.4  24.1  260  21 11   8.1   4.4
 16500  -3.4  25.9  240  17  9   8.8   4.8 |  -3.2  26.2  260  22 11   7.9   4.3
 16000  -2.1  28.2  240  16  8   8.8   4.8 |  -2.0  28.4  265  22 12   7.9   4.3
 15500  -0.7  30.7  245  15  8   8.9   4.9 |  -0.8  30.6  270  23 12   7.9   4.3
 15000   0.6  33.1  245  15  8   9.0   4.9 |   0.9  33.6  270  22 11   8.0   4.4
 14500   2.0  35.6  245  15  8   8.8   4.8 |   2.1  35.8  270  22 11   8.0   4.4
 14000   3.2  37.8  250  15  8   8.5   4.7 |   3.3  37.9  270  20 10   8.1   4.4
 13500   4.5  40.1  250  15  8   8.6   4.7 |   4.4  39.9  270  19 10   8.4   4.6
 13000   5.8  42.4  255  15  8   9.0   4.9 |   5.7  42.3  270  18  9   9.1   5.0
 12500   7.1  44.8  255  15  8   9.0   4.9 |   7.0  44.6  265  17  9   9.0   5.0
 12000   8.5  47.3  255  14  7   9.2   5.0 |   8.3  46.9  265  15  8   8.7   4.8
 11500   9.8  49.6  250  12  6   9.3   5.1 |   9.6  49.3  265  14  7   8.8   4.8
 11000  11.0  51.8  250  11  6   7.6   4.2 |  10.8  51.4  260  12  6   7.7   4.2
 10500  12.2  54.0  255  11  6  10.2   5.6 |  11.9  53.4  260  11  6  10.1   5.6
 10250  13.1  55.6  255  11  6  11.2   6.1 |  12.8  55.0  260  10  5  11.1   6.1
 10000  13.7  56.7  255  11  6   8.6   4.7 |  13.5  56.3  260  10  5   8.7   4.8
  9750  14.4  57.9  260  11  6   9.3   5.1 |  14.1  57.4  260   9  5   9.5   5.2
  9500  15.1  59.2  260  12  6   9.2   5.0 |  14.8  58.6  260   9  5   9.1   5.0
  9250  15.7  60.3  260  12  6   7.8   4.3 |  15.4  59.7  260   8  4   8.7   4.8
  9000  16.3  61.3  265  12  6   8.0   4.4 |  16.1  61.0  260   8  4   9.6   5.3
  8750  17.0  62.6  270  13  7   9.2   5.1 |  16.8  62.2  260   7  4  10.3   5.7
  8500  17.6  63.7  275  15  7   8.8   4.8 |  17.5  63.5  260   7  3  10.1   5.6
  8250  18.2  64.8  275  16  8   8.5   4.7 |  18.3  64.9  265   6  3  10.4   5.7
  8000  18.8  65.8  275  18  9   7.5   4.1 |  19.0  66.2  265   6  3  10.0   5.5
  7750  19.4  66.9  280  19 10   6.6   3.6 |  19.8  67.6  265   6  3   9.4   5.1
  7500  19.9  67.8  280  20 10   7.1   3.9 |  20.5  68.9  265   6  3   9.8   5.4
  7250  20.4  68.7  280  20 10   8.3   4.6 |  21.2  70.2  265   6  3  10.3   5.7
  7000  21.1  70.0  280  20 10   8.2   4.5 |  22.0  71.6  265   6  3  10.3   5.7
  6750  21.7  71.1  280  20 10   9.1   5.0 |  22.7  72.9  265   6  3   9.5   5.2
  6500  22.2  72.0  280  19 10   4.1   2.3 |  23.5  74.3  265   6  3  10.1   5.6
  6250  22.2  72.0  275  16  8  -0.7  -0.4 |  24.3  75.7  265   6  3  11.3   6.2
  6000  22.0  71.6  275  13  7   0.0   0.0 |  25.1  77.2  265   6  3  10.4   5.7
  5750  21.7  71.1  265  10  5  -3.7  -2.0 |  25.9  78.6  270   6  3  11.8   6.5
  5500  21.2  70.2  250   7  3  -0.6  -0.3 |  27.0  80.6  270   6  3  19.8  10.9

           06/02/2015 at 1500 MDT          |       06/02/2015 at 1800 MDT
                                           |
K index... +16.2  LI... +274.2             | K index... +15.5  LI... +273.5
CAPE... 0.0  CIN... -17.0                  | CAPE... +24.9  CIN... -53.8
                                           |
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 -62.9 -81.2  280  15  8   1.1   0.6 | -62.7 -80.9  275  14  7   1.2   0.7
 45000 -60.6 -77.1  270  24 12   3.1   1.7 | -60.4 -76.7  270  27 14   2.9   1.6
 40000 -55.6 -68.1  275  38 19   5.4   3.0 | -55.8 -68.4  275  43 22   5.6   3.1
 38000 -52.3 -62.1  270  40 20   5.5   3.0 | -52.3 -62.1  270  41 21   5.8   3.2
 36000 -49.0 -56.2  270  42 21   5.6   3.1 | -48.9 -56.0  260  40 20   5.8   3.2
 34000 -44.7 -48.5  265  40 20   7.9   4.4 | -44.5 -48.1  260  38 19   8.0   4.4
 32000 -39.9 -39.8  260  36 19   7.9   4.4 | -39.7 -39.5  260  35 18   8.0   4.4
 30000 -35.2 -31.4  255  33 17   7.8   4.3 | -35.0 -31.0  260  34 17   7.9   4.3
 29000 -32.3 -26.1  250  32 16   7.8   4.3 | -32.1 -25.8  255  33 17   7.9   4.3
 28000 -30.0 -22.0  250  31 16   7.8   4.3 | -29.7 -21.5  255  33 17   7.7   4.2
 27000 -27.6 -17.7  245  28 15   7.9   4.4 | -27.6 -17.7  255  32 16   7.2   3.9
 26000 -25.2 -13.4  235  27 14   7.9   4.4 | -25.4 -13.7  255  31 16   7.2   3.9
 25000 -22.9  -9.2  230  25 13   7.9   4.4 | -23.3  -9.9  255  30 15   7.1   3.9
 24000 -20.4  -4.7  235  23 12   8.2   4.5 | -21.0  -5.8  250  29 15   7.9   4.3
 23000 -18.0  -0.4  245  22 11   8.2   4.5 | -18.7  -1.7  255  27 14   7.9   4.3
 22000 -15.5   4.1  255  21 11   8.4   4.6 | -16.3   2.7  255  26 13   7.9   4.3
 21000 -13.4   7.9  260  22 11   6.9   3.8 | -14.0   6.8  255  24 13   7.8   4.3
 20000 -11.3  11.7  260  23 12   7.0   3.8 | -11.8  10.8  250  22 12   7.9   4.3
 19500 -10.3  13.5  260  23 12   7.0   3.8 | -10.6  12.9  250  21 11   7.9   4.3
 19000  -9.3  15.3  260  24 12   7.3   4.0 |  -9.4  15.1  250  20 11   8.5   4.7
 18500  -8.2  17.2  255  23 12   7.6   4.1 |  -8.2  17.2  250  19 10   8.8   4.8
 18000  -7.1  19.2  255  23 12   7.7   4.2 |  -6.9  19.6  245  18  9   8.8   4.8
 17500  -5.9  21.4  255  22 11   8.7   4.7 |  -5.5  22.1  245  16  8   9.0   5.0
 17000  -4.7  23.5  255  21 11   8.6   4.7 |  -4.2  24.4  240  15  8   9.0   4.9
 16500  -3.4  25.9  255  20 10   9.0   4.9 |  -2.9  26.8  240  14  7   9.1   5.0
 16000  -2.1  28.2  255  19 10   9.1   5.0 |  -1.5  29.3  235  13  6   9.2   5.0
 15500  -0.7  30.7  255  19 10   9.2   5.0 |  -0.1  31.8  235  12  6   9.1   5.0
 15000   1.3  34.3  250  17  9   9.2   5.0 |   1.9  35.4  225  11  5   9.0   4.9
 14500   2.7  36.9  250  16  8   8.8   4.8 |   3.2  37.8  225  10  5   9.0   4.9
 14000   4.0  39.2  245  14  7   8.4   4.6 |   4.6  40.3  215  10  5   9.0   4.9
 13500   5.2  41.4  245  13  7   8.5   4.7 |   5.9  42.6  210   9  5   9.0   4.9
 13000   6.5  43.7  235  12  6   8.9   4.9 |   7.2  45.0  205   9  4   8.9   4.9
 12500   7.8  46.0  230  10  5   8.8   4.9 |   8.6  47.5  195   8  4   8.9   4.9
 12000   9.1  48.4  220   9  5   8.3   4.5 |   9.9  49.8  185   8  4   8.9   4.9
 11500  10.3  50.5  210   8  4   8.4   4.6 |  11.2  52.2  185   7  4   9.0   4.9
 11000  11.5  52.7  200   7  3   8.0   4.4 |  12.4  54.3  175   6  3   7.9   4.3
 10500  12.6  54.7  185   5  3  11.0   6.0 |  13.5  56.3  165   5  2  11.1   6.1
 10250  13.6  56.5  180   5  2  12.4   6.8 |  14.5  58.1  160   4  2  11.9   6.5
 10000  14.3  57.7  180   5  2   9.4   5.2 |  15.1  59.2  155   3  2   8.2   4.5
  9750  15.1  59.2  180   4  2  10.2   5.6 |  15.8  60.4  150   3  1   9.2   5.1
  9500  15.8  60.4  180   4  2  10.0   5.5 |  16.4  61.5  140   2  1   8.9   4.9
  9250  16.5  61.7  180   4  2   8.7   4.7 |  17.1  62.8  125   2  1   9.2   5.1
  9000  17.2  63.0  180   4  2   9.1   5.0 |  17.8  64.0  110   1  1   9.8   5.4
  8750  17.9  64.2  180   4  2  10.4   5.7 |  18.5  65.3  095   1  1  10.0   5.5
  8500  18.7  65.7  180   4  2  10.0   5.5 |  19.3  66.7  070   1  0   9.8   5.4
  8250  19.5  67.1  180   4  2  11.5   6.3 |  20.0  68.0  040   1  1  10.8   5.9
  8000  20.3  68.5  180   4  2  10.7   5.9 |  20.8  69.4  020   1  1  10.1   5.6
  7750  21.0  69.8  180   3  2   8.9   4.9 |  21.5  70.7  010   2  1   8.8   4.8
  7500  21.7  71.1  180   3  2   9.6   5.2 |  22.2  72.0  005   2  1   9.3   5.1
  7250  22.5  72.5  180   3  2  10.3   5.6 |  22.9  73.2  360   2  1  10.4   5.7
  7000  23.2  73.8  180   3  2  10.4   5.7 |  23.7  74.7  355   2  1  10.6   5.8
  6750  24.0  75.2  185   3  2   9.3   5.1 |  24.5  76.1  355   2  1   9.5   5.2
  6500  24.7  76.5  185   3  2   9.9   5.4 |  25.2  77.4  350   3  1   9.5   5.2
  6250  25.5  77.9  185   3  1  11.2   6.2 |  25.9  78.6  350   3  1  10.1   5.5
  6000  26.3  79.3  185   3  1  11.1   6.1 |  26.7  80.1  350   3  2  10.2   5.6
  5750  27.1  80.8  185   2  1  10.9   6.0 |  27.4  81.3  345   3  2   9.7   5.3
  5500  28.1  82.6  190   2  1  17.0   9.3 |  28.1  82.6  345   3  2  11.8   6.5
________________________________________________________________________________

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 near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 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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