Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 220122
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1922 MDT Thursday, August 21, 2014

This forecast is for Friday, August 22, 2014:

If the trigger temperature of 76.7 F/24.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 921 ft/min (4.7 m/s)
   Maximum height of thermals.................. 13579 ft MSL (8292 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8778 ft MSL (3491 ft AGL)
Thermal soaring outlook for Saturday 08/23..... 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 PVA
Potential height of wave....................... 41036 ft MSL (35749 ft AGL)
Wave soaring outlook for Saturday 08/23........ Good

Remarks... Upper trough moving over the state...producing afternoon showers over
           the foothills and adjacent plains.

Sunrise/Sunset.................... 06:18:08 / 19:47:05 MDT
Total possible sunshine........... 13 hr 28 min 56 sec (808 min 56 sec)
Altitude of sun at 13:02:13 MDT... 61.83 degrees

Upper air data from numerical model forecast valid on 08/22/2014 at 0600 MDT

Freezing level.................. 14905 ft MSL (9618 ft AGL)
Convective condensation level... 12441 ft MSL (7154 ft AGL)
Lifted condensation level....... 12790 ft MSL (7502 ft AGL)
Lifted index.................... -1.4
K index......................... +26.8

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  -64.7 -84.5   225   46   24   1.0   0.5      M     M       M      M    M
 45000  -61.3 -78.3   225   65   33   5.2   2.9      M     M       M      M    M
 40000  -53.1 -63.6   225   72   37   7.4   4.0      M     M       M      M    M
 38000  -48.6 -55.5   220   67   35   7.4   4.1      M     M       M      M    M
 36000  -44.2 -47.6   215   62   32   7.3   4.0      M     M       M      M    M
 34000  -38.4 -37.1   210   56   29   8.7   4.7      M     M       M      M    M
 32000  -33.2 -27.8   210   51   26   9.5   5.2      M     M       M      M    M
 30000  -28.6 -19.5   210   46   24   7.6   4.2   47.8 118.0    15.6      M    M
 29000  -26.4 -15.5   215   44   22   7.6   4.2   47.0 116.6    15.1      M    M
 28000  -24.1 -11.4   215   41   21   7.2   3.9   46.3 115.3    14.7      M    M
 27000  -22.0  -7.6   215   40   20   7.0   3.9   45.1 113.2    13.9      M    M
 26000  -20.0  -4.0   220   38   20   7.1   3.9   44.1 111.4    13.2      M    M
 25000  -17.9  -0.2   220   37   19   7.1   3.9   43.2 109.8    12.6      M    M
 24000  -16.0   3.2   225   37   19   6.4   3.5   41.9 107.5    11.7      M    M
 23000  -14.1   6.6   225   38   20   6.4   3.5   40.7 105.3    10.8      M    M
 22000  -12.2  10.0   225   39   20   6.4   3.5   39.6 103.3     9.9      M    M
 21000  -10.5  13.1   220   38   20   5.7   3.1   38.1 100.6     8.7      M    M
 20000   -8.8  16.2   215   37   19   5.7   3.2   36.7  98.1     7.6      M    M
 19500   -8.0  17.6   210   37   19   5.8   3.2   36.0  96.9     7.0      M    M
 19000   -7.2  19.0   210   36   18   5.6   3.1   35.4  95.7     6.4      M    M
 18500   -6.4  20.5   210   34   17   5.6   3.1   34.6  94.3     5.8      M    M
 18000   -5.6  21.9   215   31   16   5.7   3.1   33.9  93.1     5.2      M    M
 17500   -4.7  23.5   215   28   15   6.3   3.5   33.3  91.9     4.6      M    M
 17000   -3.8  25.2   220   25   13   6.3   3.5   32.7  90.8     4.0      M    M
 16500   -2.6  27.3   220   20   10   5.6   3.1   31.7  89.1     3.1      M    M
 16000   -1.8  28.8   220   18    9   5.6   3.0   31.0  87.9     2.5      M    M
 15500   -0.9  30.4   220   16    8   6.5   3.6   30.4  86.7     1.9      M    M
 15000    0.0  32.0   225   14    7   6.5   3.6   29.9  85.7     1.3      M    M
 14500    0.9  33.6   230   12    6   6.5   3.6   29.3  84.8     0.8      M    M
 14000    1.9  35.4   235   10    5   6.6   3.6   28.8  83.8     0.3      M    M
 13500    2.9  37.2   240    8    4   6.8   3.7   28.3  82.9    -0.2    707  3.6
 13000    4.0  39.2   255    6    3   7.2   4.0   27.9  82.1    -0.5    658  3.3
 12500    5.1  41.2   275    4    2   7.8   4.3   27.5  81.4    -0.8    609  3.1
 12000    6.5  43.7   295    4    2   9.3   5.1   27.3  81.2    -0.9    553  2.8
 11500    8.0  46.4   310    4    2   9.1   5.0   27.3  81.1    -0.9    495  2.5
 11000    9.3  48.7   320    4    2   8.3   4.6   27.1  80.8    -1.0    440  2.2
 10500   10.6  51.1   325    4    2   5.7   3.1   26.9  80.4    -1.2    387  2.0
 10250   10.9  51.6   325    4    2   5.5   3.0   26.5  79.6    -1.6    370  1.9
 10000   11.4  52.5   320    4    2   9.5   5.2   26.3  79.4    -1.8    346  1.8
  9750   12.1  53.8   320    4    2   9.4   5.2   26.3  79.3    -1.9    320  1.6
  9500   12.7  54.9   315    4    2   8.0   4.4   26.3  79.3    -2.0    294  1.5
  9250   13.1  55.6   315    3    2   5.2   2.8   26.0  78.8    -2.4    274  1.4
  9000   13.4  56.1   315    3    1   6.1   3.3   25.6  78.2    -2.8    257  1.3
  8750   13.9  57.0   310    2    1   7.3   4.0   25.4  77.8    -3.0    236  1.2
  8500   14.3  57.7   305    2    1   6.8   3.8   25.2  77.4    -3.3    215  1.1
  8250   14.8  58.6   300    1    1   6.9   3.8   25.0  77.0    -3.6    194  1.0
  8000   15.2  59.4   305    1    0   6.4   3.5   24.8  76.6    -3.9    173  0.9
  7750   15.7  60.3   000    0    0   5.7   3.2   24.5  76.1    -4.2    153  0.8
  7500   16.1  61.0   095    1    0   6.0   3.3   24.2  75.5    -4.6    134  0.7
  7250   16.5  61.7   115    1    1   6.3   3.4   23.9  75.0    -4.9    113  0.6
  7000   16.9  62.4   120    2    1   6.2   3.4   23.6  74.5    -5.2     92  0.5
  6750   17.4  63.3   120    2    1   5.3   2.9   23.3  74.0    -5.5     73  0.4
  6500   17.7  63.9   135    3    1   4.2   2.3   23.0  73.3    -5.9     56  0.3
  6250   17.9  64.2   155    2    1   3.8   2.1   22.5  72.5    -6.4     41  0.2
  6000   18.2  64.8   175    3    1   4.6   2.5   22.1  71.7    -6.9     26  0.1
  5750   18.6  65.5   195    4    2   2.8   1.5   21.7  71.0    -7.2      6  0.0
  5500   18.3  64.9   200    3    1  -2.1  -1.1   21.0  69.8    -8.3      9  0.0

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

           08/22/2014 at 0900 MDT          |       08/22/2014 at 1200 MDT
                                           |
K index... +23.2  LI... +2.0               | K index... +29.4  LI... -0.7
CAPE... 0.0  CIN... -1.9                   | CAPE... +36.3  CIN... -15.8
                                           |
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 -65.1 -85.2  225  44 22   0.9   0.5 | -64.7 -84.5  220  40 21   0.7   0.4
 45000 -61.6 -78.9  220  64 33   5.6   3.0 | -61.5 -78.7  215  63 32   5.4   3.0
 40000 -53.0 -63.4  220  70 36   7.1   3.9 | -53.0 -63.4  215  68 35   7.4   4.1
 38000 -48.7 -55.7  220  68 35   7.2   3.9 | -48.5 -55.3  215  65 33   7.4   4.1
 36000 -44.4 -47.9  215  65 33   7.0   3.8 | -44.0 -47.2  210  62 32   7.3   4.0
 34000 -39.3 -38.7  215  59 31   8.7   4.8 | -38.0 -36.4  210  56 29   9.1   5.0
 32000 -33.4 -28.1  215  53 27   9.5   5.2 | -32.6 -26.7  205  50 26  10.0   5.5
 30000 -28.6 -19.5  210  49 25   7.9   4.3 | -27.9 -18.2  205  46 24   7.7   4.2
 29000 -26.3 -15.3  210  47 24   7.9   4.3 | -25.6 -14.1  205  44 22   7.7   4.2
 28000 -24.0 -11.2  210  45 23   7.0   3.8 | -23.3  -9.9  205  41 21   7.4   4.0
 27000 -22.0  -7.6  210  42 22   6.8   3.7 | -21.2  -6.2  210  39 20   7.2   4.0
 26000 -20.0  -4.0  215  39 20   6.8   3.7 | -19.1  -2.4  210  37 19   7.3   4.0
 25000 -18.0  -0.4  215  37 19   6.8   3.7 | -16.9   1.6  215  34 18   7.3   4.0
 24000 -16.0   3.2  220  35 18   7.0   3.8 | -15.2   4.6  215  32 17   5.7   3.2
 23000 -13.9   7.0  220  33 17   7.0   3.9 | -13.5   7.7  215  30 16   5.8   3.2
 22000 -11.9  10.6  225  32 17   6.9   3.8 | -11.8  10.8  215  28 15   5.8   3.2
 21000 -10.2  13.6  225  32 17   5.6   3.1 | -10.1  13.8  215  27 14   5.8   3.2
 20000  -8.5  16.7  220  33 17   5.6   3.1 |  -8.4  16.9  215  26 14   5.8   3.2
 19500  -7.7  18.1  220  33 17   5.7   3.1 |  -7.6  18.3  220  26 13   5.8   3.2
 19000  -6.9  19.6  220  33 17   5.1   2.8 |  -6.7  19.9  220  25 13   6.2   3.4
 18500  -6.2  20.8  220  34 17   5.0   2.7 |  -5.8  21.6  220  25 13   6.3   3.4
 18000  -5.4  22.3  215  34 18   5.2   2.8 |  -4.9  23.2  220  24 13   6.2   3.4
 17500  -4.6  23.7  215  34 17   6.4   3.5 |  -4.1  24.6  225  24 12   5.2   2.9
 17000  -3.6  25.5  215  32 17   6.2   3.4 |  -3.0  26.6  225  24 12   5.3   2.9
 16500  -2.7  27.1  215  31 16   6.8   3.8 |  -2.2  28.0  220  23 12   5.2   2.8
 16000  -1.2  29.8  215  26 13   7.2   4.0 |  -1.5  29.3  215  23 12   5.2   2.9
 15500  -0.4  31.3  215  23 12   4.8   2.6 |  -0.8  30.6  215  23 12   4.7   2.6
 15000   0.3  32.5  205  19 10   4.9   2.7 |  -0.1  31.8  210  22 12   4.7   2.6
 14500   0.9  33.6  200  16  8   5.6   3.1 |   0.6  33.1  205  22 11   5.7   3.1
 14000   1.8  35.2  190  13  7   5.9   3.2 |   1.5  34.7  200  20 10   6.3   3.5
 13500   2.6  36.7  175  11  6   6.2   3.4 |   2.5  36.5  190  19 10   6.8   3.7
 13000   3.6  38.5  160   9  4   6.5   3.6 |   3.6  38.5  185  19 10   7.7   4.2
 12500   4.6  40.3  135   7  4   7.1   3.9 |   4.7  40.5  175  19 10   7.5   4.1
 12000   5.9  42.6  120   7  4   8.8   4.8 |   5.7  42.3  170  18  9   7.1   3.9
 11500   7.3  45.1  100   7  3   8.4   4.6 |   6.7  44.1  170  18  9   7.2   3.9
 11000   8.4  47.1  085   6  3   6.7   3.7 |   7.7  45.9  165  16  8   7.5   4.1
 10500   9.5  49.1  060   5  3   4.1   2.3 |   8.8  47.8  160  13  7   5.8   3.2
 10250   9.6  49.3  055   5  3   3.6   2.0 |   9.0  48.2  155  13  6   2.5   1.4
 10000  10.1  50.2  035   5  3   7.6   4.2 |   9.3  48.7  150  11  6   3.1   1.7
  9750  10.7  51.3  015   5  3   7.7   4.2 |   9.6  49.3  145   9  5   3.8   2.1
  9500  11.2  52.2  360   6  3   7.0   3.8 |   9.9  49.8  130   8  4   3.4   1.9
  9250  11.7  53.1  355   7  4   5.6   3.1 |  10.2  50.4  115   6  3   2.6   1.4
  9000  12.1  53.8  345   8  4   6.9   3.8 |  10.4  50.7  090   4  2   4.3   2.4
  8750  12.7  54.9  340   9  5   8.0   4.4 |  10.9  51.6  035   3  2   5.1   2.8
  8500  13.3  55.9  335  10  5   8.0   4.4 |  11.3  52.3  360   6  3   6.9   3.8
  8250  13.9  57.0  330  11  6   8.5   4.7 |  11.9  53.4  355   7  3  10.0   5.5
  8000  14.5  58.1  330  12  6   8.0   4.4 |  12.7  54.9  350   7  4   9.8   5.4
  7750  15.1  59.2  325  13  6   7.3   4.0 |  13.4  56.1  350   8  4   9.5   5.2
  7500  15.6  60.1  320  13  7   7.1   3.9 |  14.1  57.4  350   8  4   9.9   5.4
  7250  16.1  61.0  320  13  7   7.1   3.9 |  14.9  58.8  345   8  4  10.1   5.5
  7000  16.6  61.9  315  14  7   7.0   3.9 |  15.6  60.1  345   8  4  10.3   5.7
  6750  17.2  63.0  310  14  7   7.2   3.9 |  16.4  61.5  345   8  4  10.9   6.0
  6500  17.7  63.9  310  14  7   7.5   4.1 |  17.2  63.0  345   8  4  10.4   5.7
  6250  18.2  64.8  305  13  6   8.1   4.4 |  18.0  64.4  345   8  4  10.5   5.7
  6000  18.6  65.5  300  11  6   6.6   3.6 |  18.8  65.8  345   8  4   8.9   4.9
  5750  19.1  66.4  295  10  5   9.7   5.3 |  19.4  66.9  345   8  4  10.7   5.9
  5500  20.1  68.2  295   8  4  18.8  10.3 |  20.5  68.9  345   8  4  18.5  10.1

           08/22/2014 at 1500 MDT          |       08/22/2014 at 1800 MDT
                                           |
K index... +30.0  LI... -0.3               | K index... +30.2  LI... -0.6
CAPE... +36.5  CIN... -24.1                | CAPE... +20.0  CIN... -31.7
                                           |
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 -64.8 -84.6  210  38 20   0.5   0.3 | -64.6 -84.3  205  36 19   0.9   0.5
 45000 -61.6 -78.9  210  61 32   5.7   3.1 | -61.3 -78.3  205  56 29   5.1   2.8
 40000 -52.2 -62.0  205  64 33   7.8   4.3 | -52.5 -62.5  195  66 34   8.5   4.6
 38000 -47.6 -53.7  205  59 30   7.8   4.3 | -47.5 -53.5  195  62 32   8.4   4.6
 36000 -42.9 -45.2  205  54 28   8.1   4.4 | -42.4 -44.3  195  58 30   8.4   4.6
 34000 -37.4 -35.3  205  54 28   9.4   5.2 | -37.4 -35.3  195  54 28   8.5   4.6
 32000 -31.7 -25.1  205  53 27   9.3   5.1 | -32.3 -26.1  195  49 25   8.3   4.5
 30000 -27.2 -17.0  210  50 26   7.2   3.9 | -27.5 -17.5  195  45 23   7.9   4.3
 29000 -25.1 -13.2  210  48 25   7.2   3.9 | -25.2 -13.4  195  44 22   7.9   4.4
 28000 -23.0  -9.4  210  46 23   7.1   3.9 | -22.9  -9.2  195  42 22   7.6   4.2
 27000 -20.5  -4.9  210  44 23   6.9   3.8 | -20.3  -4.5  200  40 21   6.9   3.8
 26000 -18.5  -1.3  210  42 22   6.9   3.8 | -18.3  -0.9  200  39 20   6.9   3.8
 25000 -16.5   2.3  210  41 21   6.8   3.7 | -16.3   2.7  200  37 19   6.8   3.7
 24000 -14.6   5.7  210  40 21   6.3   3.5 | -14.5   5.9  200  35 18   6.2   3.4
 23000 -12.7   9.1  210  39 20   6.4   3.5 | -12.7   9.1  200  34 17   6.2   3.4
 22000 -10.9  12.4  210  38 19   6.2   3.4 | -10.9  12.4  200  32 16   6.2   3.4
 21000  -9.3  15.3  210  36 19   5.6   3.1 |  -9.2  15.4  195  30 16   5.9   3.2
 20000  -7.6  18.3  210  34 18   5.7   3.1 |  -7.5  18.5  195  29 15   5.9   3.3
 19500  -6.8  19.8  210  34 17   5.7   3.1 |  -6.6  20.1  195  29 15   6.0   3.3
 19000  -6.0  21.2  210  33 17   5.2   2.8 |  -5.8  21.6  190  28 14   5.4   3.0
 18500  -5.3  22.5  210  32 17   5.1   2.8 |  -5.0  23.0  190  27 14   5.3   2.9
 18000  -4.6  23.7  210  32 16   5.1   2.8 |  -4.3  24.3  190  27 14   5.4   2.9
 17500  -3.8  25.2  210  30 16   4.9   2.7 |  -3.5  25.7  190  26 14   5.6   3.1
 17000  -3.1  26.4  210  28 15   4.9   2.7 |  -2.7  27.1  190  26 13   5.6   3.1
 16500  -2.4  27.7  210  27 14   5.2   2.9 |  -1.9  28.6  185  26 13   5.1   2.8
 16000  -1.7  28.9  210  27 14   5.3   2.9 |  -1.2  29.8  190  25 13   5.0   2.7
 15500  -0.9  30.4  210  27 14   5.1   2.8 |  -0.5  31.1  190  24 12   5.2   2.9
 15000  -0.2  31.6  205  26 14   4.9   2.7 |   0.3  32.5  190  23 12   5.7   3.1
 14500   0.5  32.9  205  26 13   4.9   2.7 |   1.1  34.0  190  23 12   5.7   3.1
 14000   1.6  34.9  200  25 13   5.6   3.1 |   2.6  36.7  190  22 12   7.3   4.0
 13500   2.5  36.5  200  24 12   6.7   3.7 |   3.7  38.7  195  22 12   7.1   3.9
 13000   3.6  38.5  195  23 12   8.2   4.5 |   4.6  40.3  195  22 11   6.6   3.6
 12500   4.8  40.6  195  22 11   8.0   4.4 |   5.5  41.9  200  21 11   6.6   3.6
 12000   5.8  42.4  185  21 11   7.2   3.9 |   6.5  43.7  200  20 10   6.6   3.6
 11500   6.8  44.2  180  20 11   7.1   3.9 |   7.4  45.3  205  20 10   6.5   3.6
 11000   7.8  46.0  170  20 10   6.3   3.5 |   8.2  46.8  205  19 10   5.7   3.1
 10500   8.7  47.7  165  19 10   4.7   2.6 |   9.1  48.4  205  17  9   4.5   2.5
 10250   8.9  48.0  165  19 10   3.5   1.9 |   9.3  48.7  205  17  9   4.2   2.3
 10000   9.2  48.6  165  17  9   6.3   3.4 |   9.7  49.5  205  16  8   6.5   3.5
  9750   9.7  49.5  165  15  8   7.2   3.9 |  10.2  50.4  200  15  7   6.9   3.8
  9500  10.2  50.4  170  13  7   5.9   3.3 |  10.6  51.1  200  13  7   6.2   3.4
  9250  10.5  50.9  170  11  6   3.7   2.0 |  11.0  51.8  200  12  6   3.5   1.9
  9000  10.7  51.3  175   9  5   1.2   0.6 |  11.2  52.2  195  11  6   3.4   1.9
  8750  10.7  51.3  175   6  3  -0.2  -0.1 |  11.5  52.7  195  10  5   4.8   2.6
  8500  10.8  51.4  175   4  2   0.6   0.3 |  11.8  53.2  190   8  4   4.1   2.3
  8250  10.8  51.4  175   2  1   0.8   0.4 |  12.1  53.8  185   7  4   3.5   1.9
  8000  10.9  51.6  170   1  0   1.7   0.9 |  12.3  54.1  190   6  3   3.2   1.8
  7750  11.1  52.0  000   0  0   2.5   1.4 |  12.5  54.5  190   5  3   3.4   1.9
  7500  11.4  52.5  000   0  0   5.6   3.1 |  12.8  55.0  200   4  2   2.6   1.4
  7250  11.9  53.4  000   0  0   8.0   4.4 |  12.9  55.2  205   4  2   1.9   1.0
  7000  12.5  54.5  245   1  0   7.6   4.2 |  13.1  55.6  220   3  2   1.6   0.9
  6750  13.1  55.6  240   1  1   9.1   5.0 |  13.2  55.8  230   3  1   1.8   1.0
  6500  13.8  56.8  235   1  1   9.9   5.5 |  13.5  56.3  240   2  1   7.1   3.9
  6250  14.5  58.1  235   1  1  10.1   5.5 |  14.2  57.6  235   2  1  10.7   5.9
  6000  15.2  59.4  235   2  1   9.1   5.0 |  14.9  58.8  230   1  1   8.7   4.8
  5750  15.9  60.6  230   2  1  11.5   6.3 |  15.5  59.9  220   1  0  10.9   6.0
  5500  17.0  62.6  230   2  1  18.5  10.2 |  16.6  61.9  210   1  0  17.4   9.6
________________________________________________________________________________

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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