Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 240040
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1840 MDT Thursday, October 23, 2014

This forecast is for Friday, October 24, 2014:

If the trigger temperature of 77.9 F/25.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 833 ft/min (4.2 m/s)
   Maximum height of thermals.................. 14725 ft MSL (9438 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1330 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................. 10276 ft MSL (4988 ft AGL)
Thermal soaring outlook for Saturday 10/25..... 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....................... 45812 ft MSL (40525 ft AGL)
Wave soaring outlook for Saturday 10/25........ Poor

Remarks...

Sunrise/Sunset.................... 07:19:26 / 18:08:50 MDT
Total possible sunshine........... 10 hr 49 min 24 sec (649 min 24 sec)
Altitude of sun at 12:43:44 MDT... 38.34 degrees

Upper air data from numerical model forecast valid on 10/24/2014 at 0600 MDT

Freezing level.................. 15031 ft MSL (9744 ft AGL)
Convective condensation level... 21086 ft MSL (15799 ft AGL)
Lifted condensation level....... 19186 ft MSL (13898 ft AGL)
Lifted index.................... +3.2
K index......................... -6.0

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  -69.5 -93.1   300   38   20   0.8   0.5      M     M       M      M    M
 45000  -66.8 -88.2   305   56   29   5.9   3.2      M     M       M      M    M
 40000  -57.4 -71.3   310   58   30   7.4   4.1      M     M       M      M    M
 38000  -53.0 -63.4   310   57   30   7.3   4.0      M     M       M      M    M
 36000  -48.6 -55.5   315   57   29   7.3   4.0      M     M       M      M    M
 34000  -43.9 -47.0   310   51   26   8.1   4.4      M     M       M      M    M
 32000  -39.0 -38.2   300   44   23   8.1   4.4      M     M       M      M    M
 30000  -34.0 -29.2   290   40   21   8.6   4.7   42.0 107.6     9.9      M    M
 29000  -31.4 -24.5   280   40   21   8.6   4.7   41.6 106.8     9.7      M    M
 28000  -28.3 -18.9   275   40   21   7.8   4.3   41.2 106.1     9.5      M    M
 27000  -26.1 -15.0   280   38   20   7.4   4.0   40.1 104.2     8.8      M    M
 26000  -23.9 -11.0   285   37   19   7.4   4.1   39.2 102.6     8.1      M    M
 25000  -21.7  -7.1   295   37   19   7.4   4.1   38.4 101.2     7.5      M    M
 24000  -19.6  -3.3   295   35   18   7.3   4.0   37.5  99.4     6.8      M    M
 23000  -17.4   0.7   300   33   17   7.3   4.0   36.6  97.8     6.1      M    M
 22000  -15.3   4.5   305   31   16   7.3   4.0   35.8  96.4     5.5      M    M
 21000  -13.2   8.2   310   30   16   7.1   3.9   34.8  94.6     4.6      M    M
 20000  -11.1  12.0   310   30   15   7.1   3.9   33.8  92.9     3.9      M    M
 19500  -10.0  14.0   315   30   15   7.0   3.8   33.4  92.1     3.5      M    M
 19000   -8.9  16.0   315   29   15   8.2   4.5   33.0  91.5     3.2      M    M
 18500   -7.7  18.1   315   28   14   8.2   4.5   32.8  91.0     3.0      M    M
 18000   -6.4  20.5   310   27   14   7.8   4.3   32.5  90.5     2.8      M    M
 17500   -5.4  22.3   310   25   13   6.8   3.7   32.0  89.6     2.4      M    M
 17000   -4.3  24.3   310   23   12   6.8   3.7   31.5  88.8     2.0      M    M
 16500   -3.3  26.1   310   22   11   7.1   3.9   31.1  87.9     1.7      M    M
 16000   -2.2  28.0   310   20   10   7.1   3.9   30.6  87.1     1.3      M    M
 15500   -1.1  30.0   305   18    9   6.6   3.6   30.2  86.3     0.9      M    M
 15000   -0.2  31.6   305   17    9   6.1   3.4   29.6  85.2     0.4      M    M
 14500    0.8  33.4   300   15    8   6.1   3.4   29.0  84.2    -0.1    824  4.2
 14000    2.2  36.0   290   13    6   6.1   3.4   28.1  82.5    -0.9    760  3.9
 13500    3.1  37.6   285   11    6   7.3   4.0   27.5  81.5    -1.4    717  3.6
 13000    4.3  39.7   280   10    5   8.0   4.4   27.2  81.0    -1.7    667  3.4
 12500    5.5  41.9   275    9    5   8.4   4.6   27.1  80.5    -2.0    616  3.1
 12000    6.8  44.2   275    9    5   8.9   4.9   26.8  80.2    -2.2    562  2.9
 11500    8.1  46.6   275    9    5   8.9   4.9   26.7  80.0    -2.3    507  2.6
 11000    9.4  48.9   280    9    5   8.6   4.7   26.5  79.8    -2.5    453  2.3
 10500   10.8  51.4   290    9    5   4.5   2.5   26.4  79.5    -2.6    399  2.0
 10250   10.9  51.6   290    9    5   5.0   2.7   25.8  78.5    -3.2    387  2.0
 10000   11.6  52.9   295   10    5  11.5   6.3   25.8  78.5    -3.2    358  1.8
  9750   12.4  54.3   295   11    6  11.1   6.1   25.9  78.6    -3.1    327  1.7
  9500   13.2  55.8   295   13    6   9.2   5.0   26.0  78.8    -3.1    295  1.5
  9250   13.8  56.8   295   14    7   6.5   3.6   25.8  78.4    -3.3    272  1.4
  9000   14.3  57.7   295   15    8   8.1   4.4   25.6  78.1    -3.5    249  1.3
  8750   14.9  58.8   295   16    8   9.3   5.1   25.5  78.0    -3.6    222  1.1
  8500   15.6  60.1   295   17    9   7.6   4.2   25.5  77.8    -3.7    196  1.0
  8250   16.0  60.8   290   17    9   6.4   3.5   25.2  77.4    -4.0    174  0.9
  8000   16.5  61.7   290   17    9   6.3   3.5   25.0  77.0    -4.2    153  0.8
  7750   16.9  62.4   290   17    9   5.4   3.0   24.7  76.4    -4.6    133  0.7
  7500   17.2  63.0   290   17    9   4.3   2.4   24.3  75.7    -5.0    116  0.6
  7250   17.5  63.5   285   16    8   3.6   2.0   23.8  74.9    -5.5    101  0.5
  7000   17.7  63.9   285   16    8   4.2   2.3   23.4  74.1    -6.0     87  0.4
  6750   17.9  64.2   285   15    8   1.0   0.6   22.9  73.3    -6.5     73  0.4
  6500   17.7  63.9   280   13    7  -4.3  -2.4   22.0  71.6    -7.5     71  0.4
  6250   17.4  63.3   275   12    6  -1.1  -0.6   21.0  69.8    -8.5     73  0.4
  6000   17.1  62.8   270   10    5 -13.9  -7.6   20.0  68.0    -9.6     76  0.4
  5750   14.9  58.8   250    9    4 -37.7 -20.7   17.2  62.9   -12.5    133  0.7
  5500   11.8  53.2   225    7    3 -38.5 -21.1   13.5  56.2   -16.3    219  1.1

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

           10/24/2014 at 0900 MDT          |       10/24/2014 at 1200 MDT
                                           |
K index... -12.4  LI... +6.3               | K index... -11.4  LI... +6.3
CAPE... 0.0  CIN... -0.9                   | CAPE... 0.0  CIN... -0.6
                                           |
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 -70.2 -94.4  305  39 20   1.7   0.9 | -70.5 -94.9  295  36 18   2.0   1.1
 45000 -66.0 -86.8  310  51 26   6.0   3.3 | -65.7 -86.3  300  44 23   6.4   3.5
 40000 -56.9 -70.4  305  58 30   7.5   4.1 | -55.9 -68.6  305  48 25   7.6   4.2
 38000 -52.4 -62.3  305  54 28   7.4   4.0 | -51.3 -60.3  300  48 25   7.6   4.1
 36000 -48.0 -54.4  305  50 26   7.4   4.1 | -46.8 -52.2  300  48 25   7.6   4.1
 34000 -43.2 -45.8  300  44 22   8.2   4.5 | -42.2 -44.0  295  46 24   7.7   4.2
 32000 -38.3 -36.9  285  37 19   8.2   4.5 | -37.0 -34.6  290  45 23   7.6   4.2
 30000 -32.9 -27.2  285  36 19   7.9   4.3 | -32.4 -26.3  290  39 20   7.8   4.3
 29000 -30.5 -22.9  285  36 19   7.9   4.3 | -30.0 -22.0  285  37 19   7.9   4.3
 28000 -28.2 -18.8  285  36 19   7.1   3.9 | -27.7 -17.9  285  34 17   7.0   3.8
 27000 -26.2 -15.2  285  35 18   6.7   3.7 | -25.8 -14.4  280  33 17   6.4   3.5
 26000 -24.2 -11.6  285  33 17   6.7   3.7 | -23.9 -11.0  280  31 16   6.4   3.5
 25000 -22.2  -8.0  285  31 16   6.8   3.7 | -22.0  -7.6  275  30 15   6.5   3.6
 24000 -20.0  -4.0  290  31 16   7.9   4.3 | -19.7  -3.5  275  30 15   7.7   4.2
 23000 -17.6   0.3  290  32 16   7.9   4.3 | -17.4   0.7  280  29 15   7.7   4.2
 22000 -15.2   4.6  290  32 17   8.0   4.4 | -15.1   4.8  280  29 15   7.8   4.3
 21000 -12.8   9.0  290  31 16   8.3   4.6 | -12.7   9.1  280  29 15   8.1   4.4
 20000 -10.3  13.5  290  30 15   8.3   4.6 | -10.3  13.5  280  28 14   8.1   4.4
 19500  -9.0  15.8  290  29 15   8.5   4.7 |  -9.1  15.6  285  28 14   8.2   4.5
 19000  -7.9  17.8  290  28 14   6.4   3.5 |  -7.9  17.8  285  27 14   7.3   4.0
 18500  -6.9  19.6  290  26 13   6.4   3.5 |  -6.8  19.8  285  26 13   7.3   4.0
 18000  -5.9  21.4  290  24 12   6.6   3.6 |  -5.6  21.9  285  25 13   7.1   3.9
 17500  -4.9  23.2  290  23 12   6.8   3.8 |  -4.6  23.7  285  23 12   6.7   3.7
 17000  -3.9  25.0  290  22 11   6.8   3.7 |  -3.6  25.5  280  22 11   6.7   3.7
 16500  -2.8  27.0  295  21 11   7.1   3.9 |  -2.7  27.1  280  20 10   6.2   3.4
 16000  -1.7  28.9  290  20 10   7.1   3.9 |  -1.7  28.9  280  19 10   6.2   3.4
 15500  -0.7  30.7  290  19 10   6.8   3.7 |  -0.4  31.3  280  17  9   6.1   3.4
 15000   0.8  33.4  285  17  9   6.7   3.7 |   0.6  33.1  280  16  8   6.1   3.3
 14500   1.8  35.2  285  16  8   6.5   3.6 |   1.5  34.7  280  15  8   6.6   3.6
 14000   2.8  37.0  280  15  8   6.5   3.6 |   2.5  36.5  275  13  7   6.6   3.6
 13500   3.8  38.8  275  14  7   7.0   3.8 |   3.5  38.3  275  12  6   7.0   3.8
 13000   4.8  40.6  275  13  7   7.3   4.0 |   4.6  40.3  270  10  5   7.2   4.0
 12500   5.9  42.6  270  11  6   7.5   4.1 |   5.6  42.1  265   9  4   7.6   4.2
 12000   7.0  44.6  270  10  5   7.7   4.2 |   6.8  44.2  260   8  4   8.0   4.4
 11500   8.2  46.8  270   9  5   8.2   4.5 |   8.0  46.4  255   7  3   8.0   4.4
 11000   9.5  49.1  275   8  4   8.7   4.8 |   9.2  48.6  245   6  3   7.7   4.2
 10500  10.9  51.6  285   7  4   4.9   2.7 |  10.3  50.5  240   5  3   4.5   2.5
 10250  11.0  51.8  285   8  4   4.7   2.6 |  10.5  50.9  235   5  3   5.3   2.9
 10000  11.7  53.1  285   8  4  10.7   5.9 |  11.2  52.2  230   5  3  10.8   5.9
  9750  12.5  54.5  290   8  4  10.9   6.0 |  12.0  53.6  225   5  3  10.7   5.9
  9500  13.2  55.8  290   9  4   8.5   4.7 |  12.8  55.0  220   5  3   8.7   4.8
  9250  13.7  56.7  290   9  5   5.6   3.1 |  13.3  55.9  220   5  3   6.4   3.5
  9000  14.2  57.6  290   9  5   8.3   4.6 |  13.8  56.8  225   5  3   8.4   4.6
  8750  14.9  58.8  290   9  5  10.0   5.5 |  14.5  58.1  225   5  3   9.4   5.1
  8500  15.6  60.1  285  10  5   7.5   4.1 |  15.1  59.2  230   5  3   8.0   4.4
  8250  16.0  60.8  285  10  5   5.7   3.1 |  15.7  60.3  235   5  3   6.9   3.8
  8000  16.4  61.5  285  10  5   6.5   3.6 |  16.2  61.2  240   5  3   7.8   4.3
  7750  16.9  62.4  285  10  5   6.1   3.4 |  16.8  62.2  240   5  3   8.0   4.4
  7500  17.2  63.0  285  10  5   4.1   2.3 |  17.3  63.1  240   5  3   6.4   3.5
  7250  17.5  63.5  285  10  5   2.9   1.6 |  17.7  63.9  230   5  3   5.6   3.1
  7000  17.7  63.9  285  10  5   4.1   2.3 |  18.1  64.6  215   5  3   6.3   3.5
  6750  17.9  64.2  280  10  5   1.2   0.7 |  18.6  65.5  205   5  3   5.5   3.0
  6500  17.7  63.9  275   9  5  -3.9  -2.1 |  18.8  65.8  200   5  3   4.4   2.4
  6250  17.5  63.5  265   8  4  -0.7  -0.4 |  19.1  66.4  190   5  3   3.8   2.1
  6000  17.2  63.0  255   8  4 -12.2  -6.7 |  19.3  66.7  185   6  3   6.9   3.8
  5750  15.4  59.7  235   8  4 -28.3 -15.5 |  20.1  68.2  180   6  3  13.2   7.3
  5500  13.3  55.9  215   6  3 -20.2 -11.1 |  21.1  70.0  180   5  3  14.8   8.1

           10/24/2014 at 1500 MDT          |       10/24/2014 at 1800 MDT
                                           |
K index... -6.6  LI... +5.2                | K index... -1.0  LI... +4.8
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... -0.2
                                           |
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 -71.2 -96.2  285  31 16   2.5   1.4 | -71.7 -97.1  280  37 19   3.3   1.8
 45000 -65.6 -86.1  285  29 15   6.6   3.6 | -65.1 -85.2  265  30 15   6.7   3.7
 40000 -55.5 -67.9  290  46 24   7.4   4.1 | -54.9 -66.8  280  38 20   7.0   3.9
 38000 -51.1 -60.0  290  47 24   7.4   4.1 | -50.7 -59.3  285  42 22   7.0   3.9
 36000 -46.6 -51.9  290  48 25   7.4   4.1 | -46.5 -51.7  290  46 24   7.0   3.8
 34000 -42.0 -43.6  295  48 25   7.8   4.3 | -41.8 -43.2  295  48 25   8.0   4.4
 32000 -37.3 -35.1  295  48 25   7.8   4.3 | -37.0 -34.6  300  50 26   8.1   4.4
 30000 -31.6 -24.9  295  47 24   8.7   4.8 | -31.5 -24.7  300  47 24   8.2   4.5
 29000 -29.0 -20.2  300  46 24   8.7   4.8 | -29.0 -20.2  300  46 24   8.2   4.5
 28000 -26.4 -15.5  300  45 23   7.3   4.0 | -26.6 -15.9  300  44 23   7.6   4.1
 27000 -24.4 -11.9  295  41 21   6.7   3.7 | -24.4 -11.9  300  42 22   7.4   4.1
 26000 -22.4  -8.3  290  38 20   6.7   3.7 | -22.1  -7.8  295  40 20   7.4   4.1
 25000 -20.4  -4.7  285  35 18   6.6   3.6 | -19.9  -3.8  290  38 19   7.4   4.0
 24000 -18.6  -1.5  280  34 17   5.7   3.1 | -17.7   0.1  290  36 19   7.3   4.0
 23000 -16.9   1.6  275  33 17   5.8   3.2 | -15.5   4.1  285  35 18   7.3   4.0
 22000 -15.2   4.6  270  32 16   6.4   3.5 | -13.3   8.1  285  34 18   7.1   3.9
 21000 -12.9   8.8  270  31 16   8.0   4.4 | -11.4  11.5  280  33 17   6.5   3.6
 20000 -10.5  13.1  270  31 16   8.0   4.4 |  -9.5  14.9  275  33 17   6.5   3.6
 19500  -9.3  15.3  265  31 16   8.1   4.4 |  -8.5  16.7  270  33 17   6.5   3.6
 19000  -8.1  17.4  265  30 15   7.3   4.0 |  -7.5  18.5  270  33 17   7.4   4.0
 18500  -7.0  19.4  265  29 15   7.3   4.0 |  -6.4  20.5  270  33 17   7.3   4.0
 18000  -5.9  21.4  265  28 15   7.1   3.9 |  -5.3  22.5  265  33 17   7.1   3.9
 17500  -4.9  23.2  265  27 14   6.7   3.7 |  -4.3  24.3  265  32 16   6.7   3.7
 17000  -3.9  25.0  265  26 13   6.7   3.7 |  -3.3  26.1  270  30 16   6.8   3.7
 16500  -2.9  26.8  270  24 13   6.7   3.7 |  -2.4  27.7  270  29 15   5.6   3.1
 16000  -1.9  28.6  270  23 12   6.7   3.7 |  -1.5  29.3  270  28 14   5.7   3.1
 15500  -0.4  31.3  270  21 11   6.9   3.8 |  -0.3  31.5  270  26 13   5.6   3.1
 15000   0.6  33.1  270  19 10   6.9   3.8 |   0.5  32.9  270  25 13   5.6   3.1
 14500   1.7  35.1  275  17  9   7.1   3.9 |   1.4  34.5  270  23 12   7.2   3.9
 14000   2.8  37.0  275  16  8   7.1   3.9 |   2.4  36.3  270  22 11   7.4   4.0
 13500   3.8  38.8  275  14  7   7.4   4.0 |   3.5  38.3  270  20 10   7.9   4.4
 13000   4.9  40.8  275  13  7   7.5   4.1 |   4.6  40.3  265  18  9   8.2   4.5
 12500   6.0  42.8  275  11  6   7.6   4.2 |   5.8  42.4  265  16  8   8.4   4.6
 12000   7.2  45.0  280  10  5   7.8   4.3 |   7.1  44.8  265  14  7   8.5   4.7
 11500   8.3  46.9  280   8  4   7.7   4.2 |   8.4  47.1  265  11  6   8.2   4.5
 11000   9.5  49.1  275   6  3   7.4   4.0 |   9.6  49.3  265   9  4   7.5   4.1
 10500  10.6  51.1  270   4  2   3.8   2.1 |  10.8  51.4  260   6  3   3.7   2.0
 10250  10.7  51.3  270   4  2   5.3   2.9 |  10.9  51.6  260   6  3   5.5   3.0
 10000  11.5  52.7  250   3  2  11.1   6.1 |  11.8  53.2  255   5  3  12.0   6.6
  9750  12.2  54.0  220   3  1  10.2   5.6 |  12.6  54.7  245   5  2  10.8   5.9
  9500  13.0  55.4  190   3  1   8.5   4.7 |  13.4  56.1  235   4  2   8.9   4.9
  9250  13.5  56.3  180   3  2   6.6   3.6 |  13.9  57.0  230   4  2   6.7   3.7
  9000  14.1  57.4  170   4  2   9.2   5.1 |  14.5  58.1  225   4  2   9.0   4.9
  8750  14.8  58.6  165   4  2  10.4   5.7 |  15.3  59.5  220   3  2   9.9   5.4
  8500  15.5  59.9  160   5  2   9.0   4.9 |  16.0  60.8  215   3  2   8.9   4.9
  8250  16.1  61.0  155   5  2   8.1   4.4 |  16.6  61.9  215   3  1   8.2   4.5
  8000  16.7  62.1  150   5  3   8.6   4.7 |  17.2  63.0  210   2  1   8.7   4.8
  7750  17.3  63.1  150   5  2   9.1   5.0 |  17.9  64.2  210   2  1   9.1   5.0
  7500  18.0  64.4  150   4  2   9.7   5.3 |  18.5  65.3  210   2  1   8.8   4.8
  7250  18.7  65.7  150   4  2  10.1   5.6 |  19.1  66.4  215   1  1   8.7   4.8
  7000  19.4  66.9  150   4  2   9.6   5.3 |  19.8  67.6  225   1  0   8.7   4.8
  6750  20.1  68.2  150   4  2   9.4   5.2 |  20.4  68.7  260   1  0   8.7   4.7
  6500  20.8  69.4  150   4  2  10.1   5.5 |  21.0  69.8  290   1  0   8.7   4.8
  6250  21.6  70.9  150   4  2  10.1   5.5 |  21.7  71.1  310   1  1   8.7   4.8
  6000  22.3  72.1  155   4  2  10.3   5.6 |  22.3  72.1  320   2  1   8.9   4.9
  5750  23.2  73.8  155   3  2  12.4   6.8 |  22.8  73.0  320   2  1   5.3   2.9
  5500  24.2  75.6  155   3  2  15.1   8.3 |  22.9  73.2  315   2  1  -1.1  -0.6
________________________________________________________________________________

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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