Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 170143
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1842 MST Thursday, February 16, 2017

This forecast is for Friday, February 17, 2017:

If the trigger temperature of 61.8 F/16.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 403 ft/min (2.0 m/s)
   Maximum height of thermals.................. 10773 ft MSL (5466 ft AGL)

Forecast maximum temperature................... 65.0 F/18.8 C
Time of trigger temperature.................... 1230 MST
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................. 7963 ft MSL (2657 ft AGL)
Thermal soaring outlook for Saturday 02/18..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 34363 ft MSL (29056 ft AGL)
Wave soaring outlook for Saturday 02/18........ Poor

Remarks...

Sunrise/Sunset.................... 06:48:47 / 17:37:13 MST
Total possible sunshine........... 10 hr 48 min 26 sec (648 min 26 sec)
Altitude of sun at 12:13:18 MST... 38.56 degrees

Upper air data from numerical model forecast valid on 02/17/2017 at 0500 MST

Freezing level.................. 12839 ft MSL (7532 ft AGL)
Convective condensation level... 21748 ft MSL (16441 ft AGL)
Lifted condensation level....... 17477 ft MSL (12170 ft AGL)
Lifted index.................... +7.6
K index......................... -25.4

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  -61.4 -78.5   220   12    6   3.1   1.7      M     M       M      M    M
 45000  -56.5 -69.7   225   12    6   3.2   1.7      M     M       M      M    M
 40000  -51.7 -61.1   280   18    9   3.2   1.8      M     M       M      M    M
 38000  -51.1 -60.0   265   18    9  -0.2  -0.1      M     M       M      M    M
 36000  -51.2 -60.2   240   18    9  -0.2  -0.1      M     M       M      M    M
 34000  -50.4 -58.7   220   22   11   7.5   4.1      M     M       M      M    M
 32000  -45.5 -49.9   210   23   12   7.3   4.0      M     M       M      M    M
 30000  -40.8 -41.4   205   25   13   8.8   4.8   34.5  94.2    12.2      M    M
 29000  -38.2 -36.8   205   25   13   8.8   4.8   34.1  93.3    12.0      M    M
 28000  -35.5 -31.9   205   25   13   8.8   4.8   33.8  92.8    11.9      M    M
 27000  -32.9 -27.2   205   25   13   8.1   4.4   33.5  92.2    11.9      M    M
 26000  -30.6 -23.1   210   25   13   7.9   4.3   32.6  90.8    11.4      M    M
 25000  -28.2 -18.8   215   25   13   7.9   4.3   32.0  89.5    10.9      M    M
 24000  -25.8 -14.4   220   25   13   8.2   4.5   31.4  88.5    10.6      M    M
 23000  -23.2  -9.8   225   25   13   8.7   4.8   30.9  87.6    10.3      M    M
 22000  -20.6  -5.1   235   25   13   8.7   4.8   30.5  86.9    10.1      M    M
 21000  -18.0  -0.4   240   25   13   8.5   4.6   30.2  86.4    10.0      M    M
 20000  -15.5   4.1   245   25   13   8.3   4.6   29.6  85.3     9.6      M    M
 19500  -14.3   6.3   245   25   13   8.3   4.6   29.4  84.9     9.4      M    M
 19000  -13.0   8.6   250   25   13   8.3   4.6   29.2  84.5     9.3      M    M
 18500  -11.8  10.8   250   26   13   8.0   4.4   29.0  84.1     9.2      M    M
 18000  -10.7  12.7   250   26   13   6.7   3.7   28.5  83.3     8.8      M    M
 17500   -9.7  14.5   255   26   13   6.8   3.7   28.0  82.3     8.4      M    M
 17000   -8.2  17.2   255   25   13   6.4   3.5   27.1  80.9     7.7      M    M
 16500   -7.3  18.9   255   24   12   6.3   3.5   26.6  79.8     7.3      M    M
 16000   -6.3  20.7   250   23   12   6.8   3.7   26.0  78.9     6.8      M    M
 15500   -5.3  22.5   245   21   11   6.8   3.7   25.5  77.9     6.4      M    M
 15000   -4.3  24.3   240   20   10   7.2   3.9   25.0  77.1     6.0      M    M
 14500   -3.2  26.2   235   19   10   7.4   4.1   24.7  76.4     5.7      M    M
 14000   -2.0  28.4   230   18    9   7.1   3.9   24.3  75.7     5.4      M    M
 13500   -1.1  30.0   225   17    9   6.1   3.3   23.7  74.7     4.9      M    M
 13000   -0.2  31.6   220   16    8   6.0   3.3   23.1  73.6     4.4      M    M
 12500    0.5  32.9   220   14    7   4.0   2.2   22.3  72.2     3.6      M    M
 12000    1.2  34.2   215   13    7   4.4   2.4   21.4  70.6     2.8      M    M
 11500    1.5  34.7   210   11    6   1.2   0.7   20.3  68.5     1.7      M    M
 11000    1.7  35.1   205    9    5   1.2   0.7   19.0  66.2     0.5      M    M
 10500    2.2  36.0   200    7    4   5.5   3.0   18.0  64.4    -0.5    382  1.9
 10250    2.6  36.7   200    6    3   5.2   2.8   17.6  63.7    -0.8    364  1.8
 10000    3.0  37.4   195    4    2   6.1   3.4   17.3  63.1    -1.1    344  1.7
  9750    3.5  38.3   185    3    1   7.2   3.9   17.0  62.7    -1.4    321  1.6
  9500    4.1  39.4   145    2    1   7.6   4.2   16.9  62.4    -1.6    297  1.5
  9250    4.6  40.3   105    3    1   7.8   4.3   16.7  62.0    -1.8    273  1.4
  9000    5.2  41.4   090    4    2   6.7   3.7   16.5  61.7    -1.9    249  1.3
  8750    5.6  42.1   085    5    3   6.3   3.5   16.2  61.2    -2.2    229  1.2
  8500    6.2  43.2   060    5    2   7.1   3.9   16.0  60.8    -2.5    206  1.0
  8250    6.7  44.1   040    5    3   7.1   3.9   15.8  60.4    -2.7    183  0.9
  8000    7.2  45.0   025    6    3   6.3   3.4   15.6  60.0    -2.9    160  0.8
  7750    7.5  45.5   360    6    3   1.7   0.9   15.2  59.3    -3.4    144  0.7
  7500    7.4  45.3   340    7    4  -1.1  -0.6   14.4  57.9    -4.2    139  0.7
  7250    7.4  45.3   330    8    4   0.6   0.3   13.6  56.5    -5.0    133  0.7
  7000    7.3  45.1   320   10    5  -4.8  -2.6   12.8  55.0    -5.8    128  0.7
  6750    6.6  43.9   310   11    6  -8.0  -4.4   11.4  52.6    -7.2    141  0.7
  6500    6.1  43.0   305   10    5  -4.9  -2.7   10.2  50.4    -8.4    148  0.7
  6250    5.7  42.3   300   10    5  -7.4  -4.1    9.1  48.3    -9.7    155  0.8
  6000    5.0  41.0   290    8    4  -7.2  -4.0    7.7  45.9   -11.0    166  0.8
  5750    4.3  39.7   265    6    3 -17.8  -9.8    6.2  43.2   -12.6    181  0.9
  5500    2.0  35.6   215    4    2 -39.5 -21.7    3.3  37.9   -15.6    242  1.2

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

           02/17/2017 at 0800 MST          |       02/17/2017 at 1100 MST
                                           |
K index... -14.1  LI... +9.6               | K index... +1.0  LI... +9.9
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -61.2 -78.2  235  17  9   3.3   1.8 | -60.7 -77.3  240  19 10   3.4   1.9
 45000 -55.8 -68.4  235  21 11   4.4   2.4 | -55.4 -67.7  245  23 12   5.0   2.8
 40000 -49.3 -56.7  250  16  8   4.4   2.4 | -47.9 -54.2  255  21 11   5.0   2.7
 38000 -49.5 -57.1  255  16  8  -3.7  -2.0 | -47.8 -54.0  250  20 10  -3.5  -1.9
 36000 -51.7 -61.1  260  17  9  -3.7  -2.0 | -49.9 -57.8  240  20 10  -3.5  -1.9
 34000 -52.5 -62.5  265  19 10   9.5   5.2 | -51.1 -60.0  235  20 10   7.7   4.2
 32000 -46.6 -51.9  295  24 12   8.8   4.9 | -46.6 -51.9  275  24 13   6.6   3.6
 30000 -41.2 -42.2  305  29 15   9.5   5.2 | -42.2 -44.0  285  31 16   9.0   4.9
 29000 -38.3 -36.9  305  30 16   9.4   5.2 | -39.5 -39.1  285  30 16   9.1   5.0
 28000 -35.5 -31.9  305  31 16   9.4   5.2 | -36.8 -34.2  285  30 15   9.1   5.0
 27000 -32.7 -26.9  305  32 16   8.8   4.8 | -34.1 -29.4  285  30 15   8.8   4.8
 26000 -30.1 -22.2  305  31 16   8.5   4.7 | -31.5 -24.7  285  29 15   8.6   4.7
 25000 -27.6 -17.7  305  31 16   8.5   4.7 | -29.0 -20.2  285  29 15   8.6   4.7
 24000 -25.1 -13.2  305  30 16   8.7   4.8 | -26.4 -15.5  290  29 15   8.6   4.7
 23000 -22.3  -8.1  295  25 13   9.1   5.0 | -23.8 -10.8  290  28 14   8.5   4.7
 22000 -19.6  -3.3  285  21 11   9.1   5.0 | -21.3  -6.3  290  26 13   8.5   4.7
 21000 -16.9   1.6  270  18  9   7.3   4.0 | -18.7  -1.7  290  25 13   8.2   4.5
 20000 -15.2   4.6  265  16  8   5.8   3.2 | -16.3   2.7  280  23 12   7.9   4.3
 19500 -14.4   6.1  260  16  8   5.8   3.2 | -15.2   4.6  275  22 11   7.9   4.3
 19000 -13.6   7.5  260  15  8   5.8   3.2 | -14.0   6.8  270  21 11   7.9   4.3
 18500 -12.7   9.1  255  14  7   5.6   3.1 | -12.8   9.0  260  21 11   7.4   4.1
 18000 -12.1  10.2  255  14  7   3.9   2.1 | -12.1  10.2  255  20 10   3.2   1.7
 17500 -11.5  11.3  250  14  7   3.9   2.2 | -11.6  11.1  250  18  9   3.5   1.9
 17000 -10.8  12.6  245  13  7   5.1   2.8 | -10.8  12.6  245  16  8   4.1   2.2
 16500  -9.5  14.9  245  13  7   5.3   2.9 | -10.2  13.6  240  15  8   4.1   2.2
 16000  -8.6  16.5  240  13  7   6.5   3.6 |  -9.6  14.7  235  14  7   5.0   2.8
 15500  -7.6  18.3  240  13  7   6.6   3.6 |  -8.8  16.2  240  13  7   5.1   2.8
 15000  -6.6  20.1  240  13  7   6.4   3.5 |  -8.0  17.6  240  12  6   5.1   2.8
 14500  -5.7  21.7  240  13  7   6.1   3.3 |  -7.2  19.0  240  11  6   5.0   2.8
 14000  -4.7  23.5  240  14  7   5.6   3.1 |  -6.5  20.3  240  10  5   5.0   2.7
 13500  -4.1  24.6  240  14  7   4.2   2.3 |  -5.7  21.7  240   9  5   4.8   2.6
 13000  -3.4  25.9  240  13  7   4.3   2.4 |  -5.0  23.0  240   9  5   4.8   2.6
 12500  -2.8  27.0  240  12  6   4.9   2.7 |  -4.3  24.3  230   8  4   4.8   2.6
 12000  -2.1  28.2  240  11  6   4.9   2.7 |  -3.6  25.5  220   8  4   4.9   2.7
 11500  -1.4  29.5  235   9  5   5.1   2.8 |  -2.6  27.3  205   8  4   7.9   4.3
 11000  -0.6  30.9  240   8  4   5.1   2.8 |  -1.4  29.5  190   8  4   7.7   4.2
 10500   0.3  32.5  230   6  3   6.8   3.7 |  -0.3  31.5  180  10  5   7.7   4.2
 10250   0.8  33.4  225   5  2   6.9   3.8 |   0.3  32.5  175  11  6   8.2   4.5
 10000   1.4  34.5  205   4  2   8.3   4.5 |   1.0  33.8  175  12  6   9.4   5.1
  9750   2.0  35.6  190   4  2   7.7   4.2 |   1.6  34.9  175  13  7   8.1   4.5
  9500   2.5  36.5  190   3  2   6.6   3.6 |   2.1  35.8  175  12  6   6.7   3.7
  9250   3.0  37.4  190   3  2   7.0   3.8 |   2.7  36.9  180  11  6   7.4   4.1
  9000   3.5  38.3  190   3  1   6.5   3.6 |   3.2  37.8  185  10  5   6.0   3.3
  8750   3.9  39.0  210   2  1   5.9   3.2 |   3.6  38.5  190   9  5   5.9   3.2
  8500   4.4  39.9  260   2  1   5.9   3.2 |   4.1  39.4  195   7  4   7.3   4.0
  8250   4.8  40.6  290   4  2   5.6   3.1 |   4.6  40.3  205   6  3   6.4   3.5
  8000   5.2  41.4  300   5  3   6.9   3.8 |   5.1  41.2  220   4  2   8.5   4.6
  7750   5.7  42.3  300   8  4   6.8   3.7 |   5.8  42.4  250   4  2   8.2   4.5
  7500   6.2  43.2  305   9  5   5.4   3.0 |   6.2  43.2  265   5  3   6.2   3.4
  7250   6.6  43.9  305  10  5   5.5   3.0 |   6.7  44.1  275   6  3   6.5   3.6
  7000   6.9  44.4  300  12  6   4.8   2.6 |   7.1  44.8  280   7  4   5.3   2.9
  6750   7.1  44.8  300  15  8   0.1   0.1 |   7.4  45.3  275   7  4   3.8   2.1
  6500   7.0  44.6  295  17  9  -0.5  -0.3 |   7.6  45.7  265   6  3   2.4   1.3
  6250   6.8  44.2  290  19 10  -7.3  -4.0 |   7.8  46.0  260   6  3   5.0   2.7
  6000   5.8  42.4  285  16  8 -16.3  -8.9 |   8.3  46.9  255   5  2   7.6   4.2
  5750   4.5  40.1  275  12  6 -19.7 -10.8 |   8.9  48.0  250   3  2   7.8   4.3
  5500   2.6  36.7  255   8  4 -29.0 -15.9 |   9.6  49.3  250   3  1  13.9   7.7

           02/17/2017 at 1400 MST          |       02/17/2017 at 1700 MST
                                           |
K index... +6.2  LI... +7.7                | K index... +5.4  LI... +5.9
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... M
                                           |
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 -61.5 -78.7  255  19 10   3.4   1.9 | -61.3 -78.3  255  23 12   3.1   1.7
 45000 -55.9 -68.6  275  23 12   5.3   2.9 | -56.2 -69.2  270  28 14   5.3   2.9
 40000 -48.0 -54.4  260  22 11   5.3   2.9 | -48.4 -55.1  270  37 19   5.2   2.9
 38000 -47.8 -54.0  255  23 12  -3.2  -1.8 | -48.1 -54.6  265  35 18  -3.0  -1.7
 36000 -49.7 -57.5  240  25 13  -3.2  -1.8 | -49.9 -57.8  255  28 14  -3.1  -1.7
 34000 -50.9 -59.6  235  27 14   7.5   4.1 | -50.9 -59.6  245  23 12   8.0   4.4
 32000 -46.6 -51.9  250  28 15   6.4   3.5 | -46.8 -52.2  260  26 13   6.8   3.8
 30000 -42.4 -44.3  265  31 16   8.9   4.9 | -41.8 -43.2  275  29 15   9.2   5.0
 29000 -39.7 -39.5  265  33 17   8.9   4.9 | -39.0 -38.2  275  28 15   9.3   5.1
 28000 -37.0 -34.6  270  35 18   9.0   4.9 | -36.2 -33.2  275  27 14   9.3   5.1
 27000 -34.3 -29.7  275  36 19   8.8   4.8 | -33.5 -28.3  275  26 13   8.7   4.8
 26000 -31.7 -25.1  270  36 19   8.7   4.8 | -31.0 -23.8  270  23 12   8.1   4.4
 25000 -29.1 -20.4  265  36 18   8.7   4.8 | -28.6 -19.5  260  21 11   8.1   4.5
 24000 -26.5 -15.7  265  36 18   8.6   4.7 | -26.2 -15.2  255  19 10   8.1   4.5
 23000 -24.1 -11.4  260  35 18   7.9   4.3 | -23.8 -10.8  245  21 11   8.2   4.5
 22000 -21.8  -7.2  260  33 17   7.9   4.4 | -21.3  -6.3  245  25 13   8.2   4.5
 21000 -19.4  -2.9  260  32 16   7.7   4.2 | -18.9  -2.0  240  28 14   7.4   4.1
 20000 -17.2   1.0  260  29 15   7.4   4.1 | -17.2   1.0  240  27 14   5.7   3.1
 19500 -16.1   3.0  260  27 14   7.4   4.1 | -16.3   2.7  240  26 14   5.7   3.1
 19000 -15.0   5.0  265  25 13   7.4   4.1 | -15.5   4.1  240  26 13   5.7   3.1
 18500 -13.8   7.2  265  23 12   7.3   4.0 | -14.7   5.5  240  25 13   5.7   3.1
 18000 -12.9   8.8  260  22 11   5.6   3.0 | -13.6   7.5  240  24 12   7.6   4.1
 17500 -12.0  10.4  260  21 11   5.7   3.1 | -12.5   9.5  240  23 12   7.4   4.1
 17000 -11.2  11.8  255  19 10   4.2   2.3 | -11.4  11.5  245  22 11   5.4   2.9
 16500 -10.5  13.1  250  17  9   3.6   1.9 | -10.5  13.1  250  20 11   4.2   2.3
 16000  -9.9  14.2  250  16  8   4.6   2.5 |  -9.9  14.2  250  20 10   3.5   1.9
 15500  -9.2  15.4  250  15  7   4.7   2.6 |  -9.4  15.1  250  19 10   3.4   1.8
 15000  -8.6  16.5  245  13  7   4.3   2.4 |  -8.9  16.0  250  18  9   3.3   1.8
 14500  -8.0  17.6  245  12  6   3.8   2.1 |  -8.5  16.7  240  17  9   3.2   1.8
 14000  -7.4  18.7  240  10  5   4.1   2.2 |  -8.0  17.6  235  16  8   3.4   1.9
 13500  -6.7  19.9  230   9  5   4.9   2.7 |  -7.5  18.5  220  15  8   4.2   2.3
 13000  -6.0  21.2  220   9  5   4.9   2.7 |  -6.9  19.6  210  15  8   4.2   2.3
 12500  -5.2  22.6  205  10  5   5.0   2.8 |  -5.9  21.4  195  15  8   8.7   4.8
 12000  -4.5  23.9  195  12  6   5.0   2.8 |  -4.7  23.5  190  15  8   8.3   4.6
 11500  -3.5  25.7  190  13  7   8.2   4.5 |  -3.4  25.9  185  13  7   9.4   5.2
 11000  -2.3  27.9  180  14  7   8.0   4.4 |  -2.0  28.4  175  12  6   9.3   5.1
 10500  -1.2  29.8  175  14  7   7.3   4.0 |  -0.6  30.9  170  10  5   8.8   4.8
 10250  -0.7  30.7  170  13  7   8.3   4.5 |   0.1  32.2  165  10  5   9.4   5.2
 10000   0.0  32.0  165  13  6  10.5   5.7 |   0.8  33.4  160   9  5  10.5   5.8
  9750   0.8  33.4  165  12  6  10.4   5.7 |   1.6  34.9  155   9  5  10.3   5.6
  9500   1.5  34.7  160  11  6   9.5   5.2 |   2.3  36.1  150   9  5   9.6   5.3
  9250   2.3  36.1  155  10  5  10.0   5.5 |   3.1  37.6  145   9  5  10.2   5.6
  9000   3.0  37.4  155   9  5   8.9   4.9 |   3.8  38.8  135   9  5   8.4   4.6
  8750   3.6  38.5  150   8  4   8.6   4.7 |   4.4  39.9  130   9  5   8.2   4.5
  8500   4.3  39.7  145   8  4   9.6   5.3 |   5.1  41.2  125   9  5  10.0   5.5
  8250   5.0  41.0  145   7  4   8.6   4.7 |   5.8  42.4  120   9  5   9.1   5.0
  8000   5.7  42.3  140   7  4  11.6   6.3 |   6.5  43.7  115  10  5  11.0   6.0
  7750   6.6  43.9  140   7  3  11.5   6.3 |   7.4  45.3  110  10  5  10.4   5.7
  7500   7.3  45.1  135   6  3   8.5   4.6 |   8.0  46.4  105  10  5   8.2   4.5
  7250   8.0  46.4  135   6  3   9.3   5.1 |   8.6  47.5  105  10  5   8.8   4.8
  7000   8.7  47.7  135   6  3   9.3   5.1 |   9.3  48.7  100  11  5   9.2   5.0
  6750   9.4  48.9  135   6  3   9.7   5.3 |  10.0  50.0  100  11  6   9.7   5.3
  6500  10.1  50.2  130   6  3   9.8   5.4 |  10.7  51.3  095  11  6   9.7   5.3
  6250  10.9  51.6  130   5  3  10.2   5.6 |  11.5  52.7  095  11  6   9.3   5.1
  6000  11.7  53.1  130   5  3  11.1   6.1 |  12.1  53.8  090  11  6   8.3   4.6
  5750  12.5  54.5  125   5  3  10.7   5.9 |  12.7  54.9  090  10  5   8.6   4.7
  5500  13.4  56.1  125   5  2  14.2   7.8 |  13.4  56.1  085   9  5   8.6   4.7
________________________________________________________________________________

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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