Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 220124
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1923 MDT Tuesday, October 21, 2014

This forecast is for Wednesday, October 22, 2014:

If the trigger temperature of 65.5 F/18.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 462 ft/min (2.3 m/s)
   Maximum height of thermals.................. 12981 ft MSL (7694 ft AGL)

Forecast maximum temperature................... 69.0 F/21.0 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ 1500 MDT
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................. 8190 ft MSL (2902 ft AGL)
Thermal soaring outlook for Thursday 10/23..... Fair

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....................... 40021 ft MSL (34734 ft AGL)
Wave soaring outlook for Thursday 10/23........ Poor

Remarks...

Sunrise/Sunset.................... 07:17:16 / 18:11:34 MDT
Total possible sunshine........... 10 hr 54 min 17 sec (654 min 17 sec)
Altitude of sun at 12:44:00 MDT... 39.04 degrees

Upper air data from numerical model forecast valid on 10/22/2014 at 0600 MDT

Freezing level.................. 12046 ft MSL (6759 ft AGL)
Convective condensation level... 12343 ft MSL (7056 ft AGL)
Lifted condensation level....... 12486 ft MSL (7199 ft AGL)
Lifted index.................... -1.6
K index......................... +23.7

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  -61.3 -78.3   230   37   19   4.1   2.2      M     M       M      M    M
 45000  -55.6 -68.1   230   43   22   0.7   0.4      M     M       M      M    M
 40000  -54.6 -66.3   230   49   25   0.7   0.4      M     M       M      M    M
 38000  -53.2 -63.8   230   49   25   2.7   1.5      M     M       M      M    M
 36000  -51.6 -60.9   230   49   25   2.7   1.5      M     M       M      M    M
 34000  -49.2 -56.6   235   47   24   6.3   3.5      M     M       M      M    M
 32000  -44.9 -48.8   235   43   22   6.3   3.5      M     M       M      M    M
 30000  -40.7 -41.3   240   40   20   7.8   4.3   34.6  94.4    10.6      M    M
 29000  -38.3 -36.9   240   38   20   7.8   4.3   33.8  92.9    10.2      M    M
 28000  -36.0 -32.8   245   37   19   7.9   4.3   33.2  91.7     9.8      M    M
 27000  -33.6 -28.5   250   36   19   8.5   4.6   32.6  90.7     9.4      M    M
 26000  -31.0 -23.8   250   35   18   8.5   4.6   32.0  89.6     9.0      M    M
 25000  -28.5 -19.3   255   34   18   8.5   4.6   31.6  88.8     8.8      M    M
 24000  -26.0 -14.8   255   33   17   7.7   4.2   31.1  87.9     8.5      M    M
 23000  -23.7 -10.7   255   31   16   7.8   4.3   30.3  86.5     7.9      M    M
 22000  -21.4  -6.5   260   29   15   7.8   4.3   29.6  85.3     7.4      M    M
 21000  -19.2  -2.6   260   27   14   7.1   3.9   28.8  83.9     6.8      M    M
 20000  -17.1   1.2   255   24   13   7.1   3.9   27.8  82.1     6.0      M    M
 19500  -16.0   3.2   255   23   12   7.1   3.9   27.4  81.3     5.6      M    M
 19000  -15.0   5.0   250   22   11   7.2   3.9   27.0  80.5     5.3      M    M
 18500  -14.0   6.8   250   20   10   6.3   3.4   26.4  79.6     4.9      M    M
 18000  -13.1   8.4   250   19   10   6.4   3.5   25.9  78.5     4.3      M    M
 17500  -12.1  10.2   255   18    9   6.6   3.6   25.3  77.5     3.8      M    M
 17000  -11.2  11.8   255   17    9   6.7   3.7   24.8  76.6     3.4      M    M
 16500  -10.2  13.6   255   17    9   6.7   3.7   24.3  75.7     2.9      M    M
 16000   -8.7  16.3   255   15    8   6.7   3.7   23.5  74.3     2.2      M    M
 15500   -7.7  18.1   255   13    7   7.0   3.8   23.0  73.4     1.7      M    M
 15000   -6.7  19.9   255   12    6   7.6   4.1   22.6  72.6     1.3      M    M
 14500   -5.6  21.9   255   11    6   7.6   4.2   22.2  72.0     1.0      M    M
 14000   -4.5  23.9   260   10    5   7.5   4.1   21.9  71.3     0.6      M    M
 13500   -3.4  25.9   260    9    5   7.5   4.1   21.5  70.7     0.3      M    M
 13000   -2.2  28.0   265    8    4   8.3   4.6   21.2  70.2    -0.0    656  3.3
 12500   -1.0  30.2   275    8    4   8.2   4.5   21.0  69.7    -0.3    605  3.1
 12000    0.3  32.5   285    8    4   9.1   5.0   20.8  69.4    -0.5    552  2.8
 11500    1.6  34.9   295    8    4   9.1   5.0   20.7  69.2    -0.6    497  2.5
 11000    2.9  37.2   300   10    5   8.6   4.7   20.5  68.9    -0.7    443  2.3
 10500    4.2  39.6   305   11    6   9.5   5.2   20.3  68.6    -1.0    390  2.0
 10250    4.8  40.6   305   12    6   4.8   2.6   20.2  68.4    -1.0    364  1.8
 10000    5.0  41.0   305   12    6   4.9   2.7   19.7  67.4    -1.6    351  1.8
  9750    5.7  42.3   305   13    7   9.6   5.2   19.6  67.3    -1.7    324  1.6
  9500    6.3  43.3   305   14    7   8.8   4.9   19.5  67.1    -1.8    298  1.5
  9250    6.9  44.4   310   15    8   6.0   3.3   19.4  66.9    -1.9    273  1.4
  9000    7.2  45.0   310   15    8   5.4   3.0   19.0  66.2    -2.3    256  1.3
  8750    7.7  45.9   310   15    8   8.2   4.5   18.8  65.8    -2.5    232  1.2
  8500    8.3  46.9   310   15    8   7.4   4.0   18.6  65.6    -2.7    208  1.1
  8250    8.8  47.8   310   15    8   6.9   3.8   18.4  65.2    -2.9    185  0.9
  8000    9.3  48.7   315   14    7   6.5   3.6   18.2  64.8    -3.2    164  0.8
  7750    9.7  49.5   315   14    7   6.5   3.6   18.0  64.3    -3.5    142  0.7
  7500   10.2  50.4   315   13    7   6.6   3.6   17.7  63.9    -3.7    120  0.6
  7250   10.7  51.3   315   12    6   6.7   3.7   17.5  63.4    -4.0     99  0.5
  7000   11.2  52.2   320   10    5   6.7   3.7   17.2  63.0    -4.2     77  0.4
  6750   11.7  53.1   320    9    5   6.4   3.5   17.0  62.6    -4.5     55  0.3
  6500   12.1  53.8   320    7    4   5.4   3.0   16.7  62.1    -4.8     35  0.2
  6250   12.3  54.1   320    5    3   4.2   2.3   16.3  61.4    -5.3     20  0.1
  6000   12.6  54.7   315    4    2   6.3   3.5   16.0  60.7    -5.8      5  0.0
  5750   13.0  55.4   305    2    1   2.9   1.6   15.7  60.2    -6.2      M    M
  5500   12.6  54.7   255    1    1  -9.6  -5.3   14.7  58.5    -7.3      M    M

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

           10/22/2014 at 0900 MDT          |       10/22/2014 at 1200 MDT
                                           |
K index... +21.5  LI... -1.2               | K index... +19.6  LI... -1.5
CAPE... +96.3  CIN... -95.2                | CAPE... +87.7  CIN... -66.6
                                           |
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 -61.1 -78.0  240  34 18   3.5   1.9 | -60.9 -77.6  250  33 17   3.5   1.9
 45000 -56.1 -69.0  245  40 20   0.9   0.5 | -56.0 -68.8  250  34 18   1.5   0.8
 40000 -54.7 -66.5  250  40 21   0.9   0.5 | -53.9 -65.0  265  34 18   1.5   0.8
 38000 -53.3 -63.9  255  38 20   2.9   1.6 | -52.8 -63.0  270  35 18   2.0   1.1
 36000 -51.5 -60.7  260  35 18   2.9   1.6 | -51.6 -60.9  280  37 19   2.0   1.1
 34000 -49.2 -56.6  265  34 18   5.6   3.1 | -49.5 -57.1  285  39 20   6.1   3.4
 32000 -45.4 -49.7  270  36 19   5.6   3.1 | -45.4 -49.7  290  40 21   6.1   3.3
 30000 -41.5 -42.7  275  38 20   7.6   4.2 | -41.1 -42.0  290  40 20   8.2   4.5
 29000 -39.2 -38.6  275  39 20   7.6   4.2 | -38.6 -37.5  285  39 20   8.2   4.5
 28000 -36.9 -34.4  275  40 21   7.7   4.2 | -36.1 -33.0  280  38 19   8.3   4.5
 27000 -34.4 -29.9  275  40 21   9.2   5.1 | -33.6 -28.5  275  37 19   8.7   4.8
 26000 -31.6 -24.9  270  39 20   9.3   5.1 | -31.0 -23.8  270  35 18   8.8   4.8
 25000 -28.9 -20.0  265  37 19   9.3   5.1 | -28.4 -19.1  270  33 17   8.8   4.8
 24000 -26.3 -15.3  260  36 19   7.4   4.0 | -25.8 -14.4  265  32 16   7.8   4.3
 23000 -24.0 -11.2  260  33 17   7.6   4.2 | -23.5 -10.3  270  32 16   7.9   4.3
 22000 -21.8  -7.2  260  31 16   7.6   4.2 | -21.1  -6.0  270  32 16   7.9   4.3
 21000 -19.6  -3.3  260  29 15   6.6   3.6 | -19.0  -2.2  270  31 16   5.8   3.2
 20000 -17.7   0.1  265  28 14   6.7   3.7 | -17.3   0.9  265  29 15   5.9   3.2
 19500 -16.7   1.9  265  27 14   6.7   3.7 | -16.5   2.3  260  28 14   5.9   3.2
 19000 -15.7   3.7  265  27 14   6.7   3.7 | -15.6   3.9  260  27 14   6.0   3.3
 18500 -14.8   5.4  265  26 13   6.3   3.4 | -14.7   5.5  255  27 14   6.6   3.6
 18000 -13.8   7.2  265  25 13   6.3   3.5 | -13.7   7.3  250  26 14   6.5   3.6
 17500 -12.9   8.8  265  24 12   6.8   3.7 | -12.7   9.1  245  26 13   7.4   4.1
 17000 -11.9  10.6  265  22 12   7.0   3.8 | -11.6  11.1  245  24 12   7.7   4.2
 16500 -10.9  12.4  265  21 11   7.4   4.1 | -10.4  13.3  245  23 12   8.0   4.4
 16000  -9.6  14.7  270  21 11   8.9   4.9 |  -8.5  16.7  250  21 11   8.9   4.9
 15500  -7.6  18.3  275  20 10   8.7   4.8 |  -7.1  19.2  255  21 11   8.8   4.8
 15000  -6.4  20.5  275  20 10   8.5   4.7 |  -5.9  21.4  265  22 11   8.7   4.8
 14500  -5.1  22.8  280  21 11   8.4   4.6 |  -4.6  23.7  270  23 12   8.5   4.7
 14000  -3.9  25.0  280  21 11   8.0   4.4 |  -3.4  25.9  270  23 12   7.8   4.3
 13500  -2.7  27.1  280  21 11   8.0   4.4 |  -2.3  27.9  275  24 12   7.8   4.3
 13000  -1.6  29.1  280  21 11   7.3   4.0 |  -1.2  29.8  275  23 12   7.1   3.9
 12500  -0.6  30.9  280  20 11   7.4   4.1 |  -0.2  31.6  280  22 11   7.2   3.9
 12000   0.5  32.9  280  19 10   6.9   3.8 |   0.8  33.4  280  20 10   6.3   3.5
 11500   1.5  34.7  280  18  9   7.0   3.8 |   1.7  35.1  280  17  9   6.4   3.5
 11000   2.5  36.5  280  16  8   6.4   3.5 |   2.6  36.7  275  14  7   6.7   3.7
 10500   3.4  38.1  280  14  7   6.5   3.6 |   3.6  38.5  270  11  6   6.5   3.5
 10250   3.8  38.8  280  13  7   3.5   1.9 |   4.0  39.2  265  10  5   3.9   2.1
 10000   4.0  39.2  280  13  7   5.7   3.1 |   4.3  39.7  260   9  5   6.2   3.4
  9750   4.6  40.3  280  11  6   9.6   5.3 |   5.0  41.0  250   8  4   9.5   5.2
  9500   5.3  41.5  280  10  5   8.4   4.6 |   5.6  42.1  235   8  4   8.4   4.6
  9250   5.8  42.4  280   8  4   5.4   3.0 |   6.2  43.2  225   7  4   5.9   3.2
  9000   6.1  43.0  280   7  4   5.6   3.1 |   6.5  43.7  215   7  4   6.3   3.5
  8750   6.7  44.1  285   6  3   8.3   4.6 |   7.1  44.8  205   7  3   8.6   4.7
  8500   7.2  45.0  290   5  3   7.6   4.2 |   7.7  45.9  195   6  3   8.0   4.4
  8250   7.8  46.0  295   4  2   7.1   3.9 |   8.3  46.9  180   6  3   7.8   4.3
  8000   8.3  46.9  305   4  2   7.1   3.9 |   8.8  47.8  160   5  3   7.9   4.3
  7750   8.8  47.8  315   3  2   7.3   4.0 |   9.3  48.7  145   5  3   7.6   4.1
  7500   9.4  48.9  320   3  2   7.5   4.1 |   9.9  49.8  130   5  3   9.1   5.0
  7250   9.9  49.8  320   3  2   7.5   4.1 |  10.6  51.1  130   5  3  10.7   5.9
  7000  10.5  50.9  325   3  1   7.6   4.2 |  11.4  52.5  125   5  3  10.1   5.6
  6750  11.0  51.8  325   3  1   7.3   4.0 |  12.1  53.8  125   5  3   9.9   5.4
  6500  11.5  52.7  315   3  1   6.4   3.5 |  12.9  55.2  125   5  2  10.2   5.6
  6250  11.9  53.4  300   2  1   5.3   2.9 |  13.7  56.7  125   5  2  11.2   6.2
  6000  12.2  54.0  275   2  1   8.1   4.4 |  14.5  58.1  120   5  2   8.9   4.9
  5750  12.8  55.0  265   2  1   6.9   3.8 |  15.2  59.4  120   5  2  12.5   6.9
  5500  12.9  55.2  240   2  1  -2.5  -1.4 |  16.5  61.7  120   5  2  25.0  13.7

           10/22/2014 at 1500 MDT          |       10/22/2014 at 1800 MDT
                                           |
K index... +24.8  LI... -1.8               | K index... +26.3  LI... -1.5
CAPE... +164.9  CIN... -7.5                | CAPE... +101.7  CIN... -25.0
                                           |
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 -61.6 -78.9  270  29 15   3.4   1.9 | -61.5 -78.7  290  28 14   3.2   1.8
 45000 -56.7 -70.1  275  30 16   0.7   0.4 | -57.3 -71.1  295  34 18   0.1   0.1
 40000 -55.7 -68.3  285  37 19   0.7   0.4 | -57.2 -71.0  315  47 24  -0.1  -0.0
 38000 -54.3 -65.7  290  40 21   2.9   1.6 | -55.1 -67.2  315  50 26   4.3   2.3
 36000 -52.5 -62.5  295  45 23   2.9   1.6 | -52.6 -62.7  310  51 26   4.3   2.3
 34000 -49.6 -57.3  295  46 24   7.5   4.1 | -49.0 -56.2  310  49 25   8.1   4.4
 32000 -44.6 -48.3  295  42 22   7.4   4.1 | -43.6 -46.5  305  43 22   8.1   4.4
 30000 -39.9 -39.8  290  40 21   8.1   4.4 | -38.9 -38.0  305  40 21   7.6   4.2
 29000 -37.5 -35.5  290  39 20   8.1   4.4 | -36.6 -33.9  300  39 20   7.6   4.2
 28000 -35.1 -31.2  290  39 20   8.1   4.4 | -34.3 -29.7  300  39 20   7.6   4.2
 27000 -32.6 -26.7  285  38 20   8.7   4.8 | -31.8 -25.2  300  38 20   8.8   4.8
 26000 -30.0 -22.0  285  38 20   8.7   4.8 | -29.2 -20.6  295  37 19   8.9   4.9
 25000 -27.4 -17.3  280  38 20   8.7   4.8 | -26.6 -15.9  295  36 19   8.9   4.9
 24000 -25.0 -13.0  275  37 19   7.1   3.9 | -24.2 -11.6  290  35 18   6.4   3.5
 23000 -22.9  -9.2  275  34 18   7.2   3.9 | -22.3  -8.1  290  34 18   6.5   3.6
 22000 -20.7  -5.3  270  31 16   7.2   3.9 | -20.3  -4.5  285  33 17   6.6   3.6
 21000 -18.7  -1.7  270  29 15   6.6   3.6 | -18.4  -1.1  280  32 16   6.4   3.5
 20000 -16.7   1.9  270  28 14   6.7   3.7 | -16.5   2.3  280  31 16   6.4   3.5
 19500 -15.7   3.7  265  27 14   6.7   3.7 | -15.6   3.9  275  31 16   6.4   3.5
 19000 -14.8   5.4  265  27 14   6.7   3.7 | -14.6   5.7  275  30 16   6.4   3.5
 18500 -13.7   7.3  265  27 14   7.6   4.2 | -13.7   7.3  270  30 15   6.5   3.6
 18000 -12.6   9.3  265  28 14   7.6   4.2 | -12.7   9.1  270  30 15   6.5   3.6
 17500 -11.5  11.3  265  28 15   7.4   4.1 | -11.8  10.8  270  29 15   7.0   3.8
 17000 -10.4  13.3  265  26 14   7.4   4.1 | -10.7  12.7  270  28 15   7.1   3.9
 16500  -9.3  15.3  265  25 13   7.3   4.0 |  -9.2  15.4  265  26 14   7.1   3.9
 16000  -7.7  18.1  265  24 12   7.0   3.9 |  -8.2  17.2  265  24 12   7.2   3.9
 15500  -6.7  19.9  270  23 12   6.8   3.8 |  -7.1  19.2  265  22 11   7.6   4.2
 15000  -5.7  21.7  270  22 11   6.7   3.7 |  -6.0  21.2  265  20 11   8.0   4.4
 14500  -4.8  23.4  270  21 11   6.7   3.7 |  -4.8  23.4  265  19 10   8.1   4.5
 14000  -3.8  25.2  270  19 10   7.0   3.9 |  -3.6  25.5  260  17  9   8.4   4.6
 13500  -2.8  27.0  265  17  9   7.0   3.9 |  -2.3  27.9  260  16  8   8.3   4.6
 13000  -1.7  28.9  260  15  8   6.9   3.8 |  -1.1  30.0  250  15  8   7.7   4.2
 12500  -0.7  30.7  255  14  7   6.9   3.8 |  -0.0  32.0  245  14  7   7.7   4.2
 12000   0.3  32.5  245  12  6   7.1   3.9 |   1.1  34.0  240  13  7   7.5   4.1
 11500   1.3  34.3  230  11  6   6.9   3.8 |   2.2  36.0  230  11  6   7.5   4.1
 11000   2.5  36.5  215  10  5   9.4   5.1 |   3.4  38.1  220  10  5   8.9   4.9
 10500   3.8  38.8  205   8  4   8.5   4.7 |   4.7  40.5  215   8  4   7.8   4.3
 10250   4.3  39.7  195   8  4   5.1   2.8 |   5.2  41.4  215   8  4   5.6   3.1
 10000   4.7  40.5  190   7  4   8.1   4.5 |   5.7  42.3  210   8  4   8.8   4.8
  9750   5.5  41.9  185   7  3  12.0   6.6 |   6.5  43.7  205   7  4  11.5   6.3
  9500   6.3  43.3  180   6  3  10.8   5.9 |   7.3  45.1  200   6  3  10.4   5.7
  9250   7.1  44.8  170   6  3   8.5   4.6 |   8.0  46.4  195   5  3   8.1   4.5
  9000   7.6  45.7  165   6  3   8.8   4.8 |   8.6  47.5  190   5  2   8.6   4.7
  8750   8.4  47.1  165   6  3  10.8   5.9 |   9.3  48.7  180   4  2  10.6   5.8
  8500   9.1  48.4  160   5  3  10.2   5.6 |  10.0  50.0  170   3  2   9.6   5.2
  8250   9.9  49.8  155   5  3  10.4   5.7 |  10.7  51.3  150   3  2   8.6   4.7
  8000  10.7  51.3  155   5  3  10.0   5.5 |  11.3  52.3  135   3  2   8.5   4.7
  7750  11.4  52.5  155   5  3   9.0   5.0 |  12.0  53.6  120   3  2   8.5   4.7
  7500  12.1  53.8  150   5  3   9.8   5.4 |  12.6  54.7  105   4  2   9.2   5.0
  7250  12.8  55.0  150   5  3  10.8   5.9 |  13.3  55.9  100   4  2   9.9   5.4
  7000  13.6  56.5  150   5  2  10.4   5.7 |  14.0  57.2  090   4  2   9.6   5.3
  6750  14.4  57.9  145   5  2  10.0   5.5 |  14.7  58.5  085   4  2   9.3   5.1
  6500  15.1  59.2  145   5  2  10.2   5.6 |  15.4  59.7  080   5  2   9.4   5.1
  6250  15.9  60.6  145   4  2  11.1   6.1 |  16.1  61.0  075   5  2   9.3   5.1
  6000  16.7  62.1  140   4  2   9.1   5.0 |  16.8  62.2  070   5  2  10.2   5.6
  5750  17.4  63.3  140   4  2  11.7   6.4 |  17.6  63.7  065   5  3   8.4   4.6
  5500  18.6  65.5  140   4  2  21.6  11.8 |  17.9  64.2  055   4  2   2.7   1.5
________________________________________________________________________________

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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