Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 081302
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0702 MDT Monday, September 8, 2014

This forecast is for Monday, September 8, 2014:

If the trigger temperature of 80.2 F/26.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1023 ft/min (5.2 m/s)
   Maximum height of thermals.................. 17002 ft MSL (11717 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ 1600 MDT
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7330 ft MSL (2045 ft AGL)
Thermal soaring outlook for Tuesday 09/09...... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 14383 ft MSL (9098 ft AGL)
Wave soaring outlook for Tuesday 09/09......... Excellent

Remarks... Moderate westerlies aloft with gradually increasing moisture today.

Sunrise/Sunset.................... 06:34:01 / 19:20:56 MDT
Total possible sunshine........... 12 hr 46 min 55 sec (766 min 55 sec)
Altitude of sun at 12:57:01 MDT... 55.74 degrees

Upper air data from rawinsonde observation taken on 09/08/2014 at 0600 MDT

Freezing level.................. 14879 ft MSL (9594 ft AGL)
Convective condensation level... 15967 ft MSL (10682 ft AGL)
Lifted condensation level....... 16244 ft MSL (10959 ft AGL)
Lifted index.................... -0.5
K index......................... +18.5

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  -66.1 -87.0   270   44   23   6.7   3.7   82.9 181.1    31.1      M    M
 45000  -58.7 -73.7   295   87   45   2.9   1.6   70.9 159.7    25.9      M    M
 40000  -50.4 -58.7   290   94   48   6.4   3.5   60.0 140.0    20.5      M    M
 38000  -46.7 -52.1   290   91   47   4.7   2.6   56.7 134.0    18.7      M    M
 36000  -43.9 -47.0   285   81   42   4.7   2.6   52.3 126.2    16.1      M    M
 34000  -41.6 -42.9   280   69   35   4.3   2.4   47.5 117.4    13.0      M    M
 32000  -37.7 -35.9   270   56   29   8.7   4.8   45.0 112.9    11.5      M    M
 30000  -32.5 -26.5   265   59   30   8.0   4.4   44.1 111.3    11.0      M    M
 29000  -29.1 -20.4   260   53   27   8.8   4.8   43.8 110.8    10.9      M    M
 28000  -27.4 -17.3   270   49   25   5.2   2.9   42.2 107.9     9.8      M    M
 27000  -25.5 -13.9   280   46   24  12.0   6.6   40.9 105.6     9.0      M    M
 26000  -22.6  -8.7   275   46   24   9.6   5.2   40.8 105.4     8.9      M    M
 25000  -20.1  -4.2   275   46   24   4.1   2.3   40.3 104.6     8.7      M    M
 24000  -18.3  -0.9   275   45   23   6.1   3.3   38.8 101.9     7.7      M    M
 23000  -17.2   1.0   275   41   21   3.8   2.1   36.5  97.8     5.9      M    M
 22000  -15.3   4.5   275   37   19   7.1   3.9   35.4  95.6     4.9      M    M
 21000  -13.1   8.4   270   33   17   8.3   4.6   34.5  94.1     4.2      M    M
 20000  -10.8  12.6   270   29   15   4.1   2.3   33.9  92.9     3.7      M    M
 19500  -10.1  13.8   270   25   13   5.3   2.9   33.0  91.3     3.0      M    M
 19000   -9.0  15.8   270   21   11   8.8   4.8   32.6  90.7     2.7      M    M
 18500   -7.7  18.1   270   19   10   8.0   4.4   32.4  90.2     2.5      M    M
 18000   -6.9  19.6   265   16    8   4.2   2.3   31.6  89.0     1.8      M    M
 17500   -6.3  20.7   260   14    7   4.6   2.5   30.7  87.3     1.0      M    M
 17000   -5.7  21.7   255   11    6   4.4   2.4   29.9  85.8     0.1      M    M
 16500   -4.7  23.5   270   10    5   9.3   5.1   29.4  84.9    -0.4   1087  5.5
 16000   -3.4  25.9   290   10    5   9.2   5.1   29.3  84.8    -0.5   1031  5.2
 15500   -2.0  28.4   300   11    6   9.2   5.0   29.2  84.6    -0.6    976  5.0
 15000   -0.7  30.7   310   12    6   9.2   5.0   29.1  84.4    -0.7    920  4.7
 14500    1.2  34.2   300   14    7   7.5   4.1   28.8  83.9    -1.1    843  4.3
 14000    2.2  36.0   295   16    8   7.7   4.2   28.5  83.3    -1.5    796  4.0
 13500    3.4  38.1   295   17    9   9.2   5.0   28.2  82.8    -1.8    748  3.8
 13000    4.8  40.6   295   18    9   9.4   5.2   28.2  82.7    -1.9    691  3.5
 12500    6.1  43.0   295   19   10   9.4   5.2   28.2  82.7    -2.0    635  3.2
 12000    7.5  45.5   295   20   10   9.4   5.2   28.1  82.6    -2.0    579  2.9
 11500    8.9  48.0   290   21   11   9.4   5.2   28.1  82.5    -2.1    522  2.7
 11000   10.3  50.5   290   21   11   9.4   5.2   28.0  82.4    -2.2    466  2.4
 10500   11.7  53.1   285   18    9   9.4   5.1   27.9  82.3    -2.3    410  2.1
 10250   12.4  54.3   285   16    8   9.2   5.0   27.9  82.2    -2.3    382  1.9
 10000   13.0  55.4   285   16    8   9.1   5.0   27.9  82.1    -2.4    354  1.8
  9750   13.7  56.7   290   15    8   9.1   5.0   27.8  82.1    -2.5    326  1.7
  9500   14.4  57.9   290   14    7   9.1   5.0   27.8  82.0    -2.5    299  1.5
  9250   15.1  59.2   295   13    7   9.1   5.0   27.7  81.9    -2.5    271  1.4
  9000   15.8  60.4   295   12    6   9.1   5.0   27.7  81.9    -2.6    243  1.2
  8750   16.4  61.5   295   12    6   9.1   5.0   27.7  81.8    -2.7    216  1.1
  8500   17.1  62.8   290   13    6   9.1   5.0   27.6  81.7    -2.7    188  1.0
  8250   17.8  64.0   290   13    7   9.1   5.0   27.6  81.6    -2.8    161  0.8
  8000   18.5  65.3   290   13    7   9.1   5.0   27.5  81.5    -2.8    133  0.7
  7750   19.1  66.4   285   13    7   9.1   5.0   27.5  81.4    -2.9    105  0.5
  7500   19.8  67.6   285   14    7   9.0   4.9   27.4  81.3    -3.0     78  0.4
  7250   20.5  68.9   280   14    7   9.5   5.2   27.3  81.2    -3.0     50  0.3
  7000   21.2  70.2   280   15    8   7.6   4.2   27.3  81.1    -3.1     22  0.1
  6750   21.6  70.9   275   14    7   5.6   3.1   27.0  80.6    -3.4      2  0.0
  6500   21.6  70.9   270   13    7 -10.2  -5.6   26.3  79.4    -4.1      M    M
  6250   20.3  68.5   265   13    7 -11.3  -6.2   24.4  75.9    -6.1     24  0.1
  6000   19.9  67.8   260   12    6  -6.6  -3.6   23.3  73.9    -7.3     30  0.2
  5750   18.7  65.7   260    8    4 -22.7 -12.5   21.4  70.5    -9.3     60  0.3
  5500   16.8  62.2   260    4    2 -19.3 -10.6   18.9  66.0   -11.9    108  0.6

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

           09/08/2014 at 0900 MDT          |       09/08/2014 at 1200 MDT
                                           |
K index... +25.3  LI... -1.6               | K index... +23.9  LI... -1.9
CAPE... +64.8  CIN... -28.9                | CAPE... +94.7  CIN... -11.4
                                           |
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 -65.7 -86.3  290  64 33   3.6   1.9 | -66.5 -87.7  290  66 34   3.3   1.8
 45000 -59.5 -75.1  295  90 46   5.8   3.2 | -60.2 -76.4  295  92 47   6.7   3.7
 40000 -50.4 -58.7  295  94 48   5.6   3.1 | -49.7 -57.5  290  95 49   5.7   3.1
 38000 -47.0 -52.6  290  86 44   5.6   3.1 | -46.3 -51.3  290  88 45   5.7   3.1
 36000 -43.6 -46.5  290  79 41   5.6   3.1 | -42.9 -45.2  285  80 41   5.7   3.1
 34000 -40.3 -40.5  285  72 37   5.5   3.0 | -39.5 -39.1  285  72 37   5.6   3.0
 32000 -37.0 -34.6  275  65 33   5.6   3.1 | -36.2 -33.2  280  64 33   5.6   3.1
 30000 -32.6 -26.7  275  58 30   8.1   4.4 | -32.1 -25.8  280  57 29   7.5   4.1
 29000 -29.6 -21.3  275  53 27   8.1   4.5 | -29.3 -20.7  280  53 27   7.6   4.2
 28000 -27.2 -17.0  270  50 26   8.3   4.5 | -27.0 -16.6  275  50 26   7.8   4.3
 27000 -24.7 -12.5  275  48 25   8.3   4.6 | -24.7 -12.5  275  46 24   7.9   4.3
 26000 -22.2  -8.0  275  47 24   8.3   4.6 | -22.3  -8.1  275  42 22   7.9   4.3
 25000 -19.7  -3.5  275  45 23   8.5   4.7 | -20.0  -4.0  270  38 20   8.0   4.4
 24000 -18.0  -0.4  280  40 21   5.2   2.9 | -18.0  -0.4  275  35 18   6.3   3.5
 23000 -16.5   2.3  280  34 17   5.3   2.9 | -16.2   2.8  275  32 16   6.4   3.5
 22000 -14.9   5.2  285  28 14   5.4   3.0 | -14.3   6.3  280  29 15   6.4   3.5
 21000 -13.3   8.1  285  23 12   5.4   3.0 | -12.7   9.1  280  23 12   5.4   2.9
 20000 -11.7  10.9  280  19 10   5.4   3.0 | -11.1  12.0  285  16  8   5.4   3.0
 19500 -10.9  12.4  275  18  9   5.3   2.9 | -10.3  13.5  285  13  7   5.3   2.9
 19000 -10.0  14.0  275  16  8   7.3   4.0 |  -9.4  15.1  285  11  6   7.1   3.9
 18500  -8.9  16.0  270  16  8   7.5   4.1 |  -8.3  17.1  280  11  6   7.3   4.0
 18000  -7.8  18.0  270  16  8   7.6   4.2 |  -7.2  19.0  270  11  6   7.3   4.0
 17500  -6.7  19.9  265  15  8   7.6   4.2 |  -6.2  20.8  265  11  6   7.1   3.9
 17000  -5.6  21.9  265  14  7   7.6   4.2 |  -5.2  22.6  255  11  6   7.2   3.9
 16500  -4.5  23.9  265  13  7   7.8   4.3 |  -4.2  24.4  250  11  5   6.8   3.7
 16000  -3.3  26.1  265  12  6   7.9   4.3 |  -3.2  26.2  245  10  5   6.8   3.7
 15500  -2.2  28.0  265  11  6   8.2   4.5 |  -2.2  28.0  235  10  5   7.0   3.9
 15000  -1.0  30.2  265  10  5   8.4   4.6 |  -1.1  30.0  230  10  5   7.3   4.0
 14500   0.8  33.4  265   8  4   8.7   4.8 |   0.5  32.9  225   9  4   7.6   4.1
 14000   2.1  35.8  270   8  4   8.8   4.8 |   1.6  34.9  220   8  4   7.7   4.2
 13500   3.4  38.1  280   7  3   9.1   5.0 |   2.7  36.9  215   7  4   9.1   5.0
 13000   4.8  40.6  290   7  3   9.4   5.2 |   4.2  39.6  215   5  3  10.4   5.7
 12500   6.2  43.2  300   7  4   9.2   5.1 |   5.8  42.4  215   4  2  10.0   5.5
 12000   7.5  45.5  305   8  4   8.8   4.8 |   7.1  44.8  225   2  1   9.0   5.0
 11500   8.7  47.7  310   8  4   8.9   4.9 |   8.5  47.3  270   1  0   9.0   5.0
 11000  10.1  50.2  315  10  5   8.8   4.8 |   9.8  49.6  340   1  1   8.8   4.8
 10500  11.4  52.5  320  11  6   5.2   2.9 |  11.2  52.2  355   2  1   5.2   2.9
 10250  11.6  52.9  320  11  6   6.2   3.4 |  11.4  52.5  360   3  1   6.2   3.4
 10000  12.4  54.3  320  12  6  11.7   6.4 |  12.2  54.0  355   3  2  11.7   6.4
  9750  13.2  55.8  315  12  6  10.7   5.8 |  13.0  55.4  350   3  2  10.5   5.8
  9500  14.0  57.2  315  13  7   9.3   5.1 |  13.8  56.8  350   4  2   9.6   5.3
  9250  14.6  58.3  315  13  7   7.3   4.0 |  14.4  57.9  345   4  2   8.0   4.4
  9000  15.2  59.4  315  14  7   9.0   5.0 |  15.0  59.0  335   4  2   9.2   5.0
  8750  15.9  60.6  315  14  7  10.2   5.6 |  15.7  60.3  325   4  2   9.9   5.4
  8500  16.6  61.9  315  15  8   9.5   5.2 |  16.3  61.3  315   4  2   9.6   5.3
  8250  17.3  63.1  310  15  8   9.0   5.0 |  17.0  62.6  315   4  2   9.5   5.2
  8000  17.9  64.2  310  15  8   8.9   4.9 |  17.7  63.9  310   4  2   9.5   5.2
  7750  18.6  65.5  310  16  8   8.7   4.8 |  18.4  65.1  310   4  2   9.4   5.1
  7500  19.2  66.6  310  16  8   8.4   4.6 |  19.1  66.4  310   4  2   9.9   5.4
  7250  19.8  67.6  305  16  8   8.1   4.4 |  19.9  67.8  310   4  2  10.3   5.7
  7000  20.5  68.9  305  17  9   8.2   4.5 |  20.6  69.1  305   4  2  10.3   5.6
  6750  21.0  69.8  300  17  9   5.6   3.1 |  21.4  70.5  305   4  2  10.6   5.8
  6500  21.2  70.2  300  16  8   0.5   0.3 |  22.2  72.0  305   4  2  10.6   5.8
  6250  21.1  70.0  295  14  7  -1.8  -1.0 |  23.0  73.4  305   4  2  10.9   6.0
  6000  21.0  69.8  285  12  6  -0.2  -0.1 |  23.8  74.8  305   4  2   9.6   5.3
  5750  21.0  69.8  280  11  6  -1.0  -0.6 |  24.5  76.1  305   4  2  13.2   7.2
  5500  20.6  69.1  265   8  4  -5.4  -2.9 |  25.9  78.6  305   4  2  23.6  12.9

           09/08/2014 at 1500 MDT          |       09/08/2014 at 1800 MDT
                                           |
K index... +24.2  LI... -1.5               | K index... +29.7  LI... -0.1
CAPE... +24.8  CIN... -43.5                | CAPE... +20.2  CIN... -1.5
                                           |
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 -66.6 -87.9  285  63 32   3.4   1.9 | -66.5 -87.7  290  65 33   3.4   1.9
 45000 -59.5 -75.1  290  87 45   6.8   3.7 | -59.8 -75.6  290  90 46   5.9   3.3
 40000 -49.4 -56.9  290  95 49   5.8   3.2 | -50.9 -59.6  285  95 49   6.0   3.3
 38000 -46.0 -50.8  285  91 47   5.8   3.2 | -47.3 -53.1  285  89 46   6.0   3.3
 36000 -42.5 -44.5  285  87 45   5.8   3.2 | -43.7 -46.7  280  83 43   5.9   3.3
 34000 -39.0 -38.2  280  78 40   5.8   3.2 | -39.3 -38.7  275  72 37   7.5   4.1
 32000 -35.6 -32.1  275  67 35   5.9   3.2 | -34.8 -30.6  270  60 31   7.6   4.2
 30000 -30.5 -22.9  270  60 31   8.1   4.4 | -29.4 -20.9  265  48 25   8.3   4.5
 29000 -28.1 -18.6  265  57 30   8.1   4.5 | -27.0 -16.6  260  43 22   8.3   4.5
 28000 -25.7 -14.3  265  55 28   7.4   4.0 | -24.5 -12.1  260  37 19   7.4   4.1
 27000 -23.7 -10.7  265  49 25   6.9   3.8 | -22.5  -8.5  255  32 17   6.9   3.8
 26000 -21.7  -7.1  270  44 23   6.9   3.8 | -20.5  -4.9  250  28 14   6.9   3.8
 25000 -19.6  -3.3  275  39 20   6.9   3.8 | -18.4  -1.1  240  23 12   7.0   3.8
 24000 -17.7   0.1  275  34 18   6.7   3.7 | -16.5   2.3  235  21 11   6.3   3.5
 23000 -15.7   3.7  275  30 16   6.7   3.7 | -14.7   5.5  230  20 10   6.3   3.5
 22000 -13.7   7.3  280  26 14   6.7   3.7 | -12.9   8.8  220  18  9   6.3   3.5
 21000 -12.2  10.0  275  20 10   5.0   2.7 | -11.1  12.0  215  16  8   6.0   3.3
 20000 -10.7  12.7  270  14  7   5.0   2.7 |  -9.4  15.1  215  13  7   6.0   3.3
 19500 -10.0  14.0  265  10  5   4.9   2.7 |  -8.5  16.7  210  12  6   6.0   3.3
 19000  -9.1  15.6  260   8  4   7.8   4.3 |  -7.6  18.3  210  11  5   5.6   3.1
 18500  -7.8  18.0  260   9  5   8.5   4.7 |  -6.8  19.8  210  10  5   5.5   3.0
 18000  -6.6  20.1  265  10  5   8.4   4.6 |  -6.1  21.0  210   9  5   5.5   3.0
 17500  -5.5  22.1  255  10  5   7.0   3.9 |  -5.3  22.5  215   8  4   4.9   2.7
 17000  -4.4  24.1  245   9  4   7.1   3.9 |  -4.6  23.7  215   7  3   5.0   2.7
 16500  -3.3  26.1  240   8  4   7.9   4.3 |  -3.9  25.0  215   5  3   5.2   2.9
 16000  -2.2  28.0  235   9  4   8.0   4.4 |  -3.1  26.4  210   4  2   5.3   2.9
 15500  -1.0  30.2  230   9  5   7.9   4.3 |  -2.4  27.7  205   3  1   5.4   3.0
 15000   0.7  33.3  220   8  4   7.6   4.2 |  -1.2  29.8  160   2  1   5.7   3.1
 14500   1.8  35.2  210   7  4   7.5   4.1 |  -0.3  31.5  125   2  1   7.4   4.1
 14000   2.9  37.2  200   6  3   7.4   4.1 |   0.9  33.6  120   3  1   8.6   4.7
 13500   4.0  39.2  180   5  3   7.4   4.1 |   2.2  36.0  115   3  2   9.2   5.0
 13000   5.1  41.2  165   4  2   7.5   4.1 |   3.7  38.7  125   3  1  10.2   5.6
 12500   6.1  43.0  150   4  2   7.9   4.3 |   5.2  41.4  130   3  1  10.1   5.5
 12000   7.4  45.3  140   3  2   9.1   5.0 |   6.7  44.1  140   3  1   9.6   5.3
 11500   8.7  47.7  130   3  1   9.0   5.0 |   8.1  46.6  150   3  1   9.7   5.3
 11000  10.0  50.0  125   3  1   8.9   4.9 |   9.6  49.3  160   3  1   9.6   5.3
 10500  11.3  52.3  125   2  1   5.9   3.2 |  11.0  51.8  165   3  1   5.9   3.2
 10250  11.7  53.1  125   2  1   7.4   4.0 |  11.3  52.3  170   3  1   6.9   3.8
 10000  12.5  54.5  125   2  1  12.5   6.9 |  12.2  54.0  175   3  1  12.5   6.9
  9750  13.4  56.1  125   2  1  11.5   6.3 |  13.0  55.4  185   3  1  11.2   6.1
  9500  14.2  57.6  125   2  1  10.6   5.8 |  13.9  57.0  190   3  1  10.8   5.9
  9250  14.9  58.8  130   2  1   8.5   4.7 |  14.6  58.3  195   3  1   9.0   5.0
  9000  15.6  60.1  130   2  1   9.7   5.3 |  15.3  59.5  200   3  2   9.7   5.3
  8750  16.4  61.5  125   2  1  10.7   5.8 |  16.0  60.8  205   3  2  10.5   5.8
  8500  17.1  62.8  125   2  1  10.3   5.6 |  16.8  62.2  210   3  2  10.4   5.7
  8250  17.9  64.2  125   1  1  10.2   5.6 |  17.6  63.7  215   4  2  11.3   6.2
  8000  18.6  65.5  125   1  1  10.1   5.6 |  18.4  65.1  215   4  2  10.3   5.7
  7750  19.4  66.9  130   1  1  10.2   5.6 |  19.1  66.4  220   4  2   9.0   4.9
  7500  20.2  68.4  130   1  1  10.0   5.5 |  19.8  67.6  225   4  2   9.8   5.3
  7250  20.9  69.6  130   1  1   9.8   5.4 |  20.6  69.1  230   4  2  10.4   5.7
  7000  21.7  71.1  135   1  1   9.8   5.4 |  21.4  70.5  230   5  2  10.0   5.5
  6750  22.4  72.3  135   1  1   9.6   5.3 |  22.1  71.8  230   5  2   9.2   5.0
  6500  23.1  73.6  135   1  0  10.4   5.7 |  22.8  73.0  230   5  2   9.9   5.4
  6250  23.9  75.0  140   1  0  11.4   6.3 |  23.5  74.3  235   5  3  10.9   6.0
  6000  24.8  76.6  145   1  0  10.1   5.5 |  24.3  75.7  235   5  3  10.2   5.6
  5750  25.5  77.9  160   1  0  12.6   6.9 |  25.1  77.2  235   5  3   9.7   5.3
  5500  26.8  80.2  000   0  0  21.7  11.9 |  25.8  78.4  235   5  3  11.0   6.0
________________________________________________________________________________

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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