Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 290124
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1924 MDT Sunday, September 28, 2014

This forecast is for Monday, September 29, 2014:

If the trigger temperature of 71.3 F/21.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 188 ft/min (1.0 m/s)
   Maximum height of thermals.................. 10442 ft MSL (5155 ft AGL)

Forecast maximum temperature................... 73.0 F/23.2 C
Time of trigger temperature.................... 1400 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7258 ft MSL (1970 ft AGL)
Thermal soaring outlook for Tuesday 09/30...... 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....................... 45700 ft MSL (40413 ft AGL)
Wave soaring outlook for Tuesday 09/30......... Poor

Remarks... Afternoon thunderstorms likely

Sunrise/Sunset.................... 06:53:49 / 18:46:37 MDT
Total possible sunshine........... 11 hr 52 min 49 sec (712 min 49 sec)
Altitude of sun at 12:49:43 MDT... 47.64 degrees

Upper air data from numerical model forecast valid on 09/29/2014 at 0600 MDT

Freezing level.................. 13924 ft MSL (8637 ft AGL)
Convective condensation level... 13259 ft MSL (7972 ft AGL)
Lifted condensation level....... 12309 ft MSL (7022 ft AGL)
Lifted index.................... -0.7
K index......................... +22.6

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  -63.0 -81.4   240   33   17   0.9   0.5      M     M       M      M    M
 45000  -60.6 -77.1   235   60   31   4.1   2.3      M     M       M      M    M
 40000  -54.4 -65.9   230   63   32   4.7   2.6      M     M       M      M    M
 38000  -51.2 -60.2   225   63   33   5.3   2.9      M     M       M      M    M
 36000  -48.0 -54.4   225   64   33   5.3   2.9      M     M       M      M    M
 34000  -44.1 -47.4   220   62   32   7.3   4.0      M     M       M      M    M
 32000  -39.2 -38.6   220   58   30   7.3   4.0      M     M       M      M    M
 30000  -34.4 -29.9   215   55   28   8.4   4.6   41.4 106.5    14.1      M    M
 29000  -31.9 -25.4   215   53   27   8.4   4.6   40.9 105.6    13.9      M    M
 28000  -29.3 -20.7   215   52   27   8.5   4.7   40.5 104.8    13.8      M    M
 27000  -27.1 -16.8   210   50   26   6.9   3.8   39.5 103.1    13.1      M    M
 26000  -25.1 -13.2   210   47   24   7.0   3.8   38.4 101.1    12.4      M    M
 25000  -23.0  -9.4   205   45   23   7.1   3.9   37.5  99.4    11.7      M    M
 24000  -21.0  -5.8   205   43   22   6.7   3.7   36.4  97.6    11.0      M    M
 23000  -19.0  -2.2   205   42   21   6.7   3.7   35.3  95.5    10.1      M    M
 22000  -16.9   1.6   200   41   21   6.7   3.7   34.2  93.6     9.4      M    M
 21000  -14.9   5.2   200   39   20   7.0   3.8   33.2  91.8     8.6      M    M
 20000  -12.8   9.0   200   38   20   7.0   3.9   32.2  90.0     7.8      M    M
 19500  -11.8  10.8   200   38   20   7.0   3.9   31.8  89.2     7.4      M    M
 19000  -10.8  12.6   200   37   19   7.0   3.9   31.3  88.4     7.1      M    M
 18500   -9.7  14.5   200   37   19   7.0   3.9   30.8  87.5     6.7      M    M
 18000   -8.8  16.2   205   36   18   7.1   3.9   30.4  86.7     6.2      M    M
 17500   -7.7  18.1   205   34   18   7.1   3.9   29.9  85.9     5.8      M    M
 17000   -6.7  19.9   205   33   17   7.1   3.9   29.5  85.1     5.4      M    M
 16500   -5.6  21.9   205   31   16   7.1   3.9   29.0  84.3     5.1      M    M
 16000   -4.1  24.6   205   30   15   7.1   3.9   28.4  83.1     4.4      M    M
 15500   -3.1  26.4   210   29   15   6.9   3.8   27.9  82.3     4.0      M    M
 15000   -2.0  28.4   210   27   14   6.6   3.6   27.4  81.3     3.6      M    M
 14500   -1.0  30.2   210   25   13   6.6   3.6   26.9  80.4     3.2      M    M
 14000    0.0  32.0   215   22   11   6.7   3.7   26.4  79.5     2.8      M    M
 13500    1.1  34.0   215   19   10   6.7   3.7   25.9  78.6     2.4      M    M
 13000    2.2  36.0   220   16    8   7.7   4.2   25.5  77.9     2.1      M    M
 12500    3.3  37.9   220   13    6   7.5   4.1   25.1  77.2     1.7      M    M
 12000    4.5  40.1   225   10    5   8.4   4.6   24.8  76.7     1.5      M    M
 11500    5.7  42.3   235    9    5   8.6   4.7   24.6  76.3     1.2      M    M
 11000    6.7  44.1   245    8    4   6.1   3.3   24.2  75.6     0.8      M    M
 10500    7.4  45.3   265    5    3   7.1   3.9   23.7  74.6     0.0      M    M
 10250    7.8  46.0   280    5    2   4.2   2.3   23.4  74.1    -0.3    371  1.9
 10000    8.1  46.6   285    5    3   6.3   3.5   22.9  73.2    -0.8    356  1.8
  9750    8.8  47.8   300    6    3  10.6   5.8   22.9  73.2    -0.8    328  1.7
  9500    9.4  48.9   310    6    3  10.2   5.6   22.9  73.3    -0.9    300  1.5
  9250   10.1  50.2   320    7    4   7.8   4.3   22.9  73.3    -0.9    272  1.4
  9000   10.6  51.1   320    9    4   6.2   3.4   22.7  72.8    -1.2    251  1.3
  8750   11.2  52.2   320   10    5   7.8   4.3   22.5  72.5    -1.4    226  1.2
  8500   11.7  53.1   320   11    6   7.4   4.0   22.3  72.1    -1.5    202  1.0
  8250   12.3  54.1   320   13    6   6.8   3.7   22.1  71.8    -1.7    179  0.9
  8000   12.7  54.9   320   14    7   6.1   3.3   21.8  71.3    -2.0    157  0.8
  7750   13.2  55.8   320   14    7   6.1   3.4   21.6  70.8    -2.3    137  0.7
  7500   13.6  56.5   320   14    7   5.7   3.1   21.3  70.3    -2.6    117  0.6
  7250   13.9  57.0   320   14    7   5.1   2.8   20.9  69.7    -3.0     99  0.5
  7000   14.2  57.6   320   13    7   4.7   2.6   20.6  69.0    -3.4     82  0.4
  6750   14.5  58.1   325   12    6   4.5   2.4   20.2  68.3    -3.9     67  0.3
  6500   14.7  58.5   325   10    5   2.3   1.3   19.7  67.5    -4.4     53  0.3
  6250   14.7  58.5   325    8    4   0.1   0.1   19.0  66.3    -5.2     46  0.2
  6000   14.7  58.5   320    7    3   2.4   1.3   18.4  65.0    -5.9     38  0.2
  5750   14.8  58.6   315    5    3  -1.5  -0.8   17.8  64.0    -6.6     29  0.1
  5500   14.0  57.2   290    3    2 -18.2 -10.0   16.4  61.5    -8.1     44  0.2

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

           09/29/2014 at 0900 MDT          |       09/29/2014 at 1200 MDT
                                           |
K index... +21.5  LI... -1.0               | K index... +11.6  LI... -2.8
CAPE... +49.9  CIN... -150.4               | CAPE... +390.3  CIN... -36.0
                                           |
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 -62.6 -80.7  230  29 15   1.6   0.9 | -61.4 -78.5  215  32 16   1.8   1.0
 45000 -59.4 -74.9  225  55 28   3.8   2.1 | -58.1 -72.6  215  52 27   3.8   2.1
 40000 -53.6 -64.5  225  63 32   4.2   2.3 | -52.4 -62.3  220  62 32   3.8   2.1
 38000 -50.8 -59.4  220  64 33   4.8   2.6 | -50.2 -58.4  220  65 33   3.6   2.0
 36000 -47.9 -54.2  220  65 33   4.8   2.6 | -48.0 -54.4  215  67 34   3.6   2.0
 34000 -44.4 -47.9  220  63 33   6.8   3.8 | -44.5 -48.1  215  64 33   6.5   3.6
 32000 -39.8 -39.6  215  59 30   6.8   3.8 | -40.6 -41.1  215  57 29   6.5   3.6
 30000 -34.9 -30.8  210  55 28   8.9   4.9 | -35.8 -32.4  210  51 26   9.1   5.0
 29000 -32.2 -26.0  210  53 27   8.9   4.9 | -33.0 -27.4  205  48 25   9.1   5.0
 28000 -29.6 -21.3  205  51 26   9.0   5.0 | -30.3 -22.5  205  45 23   9.2   5.0
 27000 -27.4 -17.3  205  50 26   6.5   3.6 | -28.0 -18.4  205  46 24   6.8   3.8
 26000 -25.5 -13.9  210  50 25   6.5   3.5 | -26.0 -14.8  205  49 25   6.8   3.7
 25000 -23.5 -10.3  210  49 25   6.5   3.5 | -23.9 -11.0  210  52 27   6.8   3.7
 24000 -21.7  -7.1  210  48 25   6.1   3.3 | -21.9  -7.4  210  53 27   6.5   3.5
 23000 -19.9  -3.8  210  46 24   6.1   3.4 | -20.0  -4.0  205  51 26   6.5   3.6
 22000 -18.1  -0.6  205  44 23   6.2   3.4 | -18.1  -0.6  205  49 25   6.6   3.6
 21000 -16.2   2.8  200  41 21   6.9   3.8 | -16.1   3.0  200  46 24   6.7   3.7
 20000 -14.1   6.6  200  38 19   6.9   3.8 | -14.2   6.4  200  42 22   6.7   3.7
 19500 -13.1   8.4  200  36 19   7.0   3.8 | -13.2   8.2  200  40 20   6.7   3.7
 19000 -12.1  10.2  200  34 18   7.0   3.9 | -12.2  10.0  200  37 19   6.7   3.7
 18500 -11.1  12.0  195  32 17   7.1   3.9 | -11.2  11.8  200  35 18   6.1   3.3
 18000 -10.0  14.0  195  31 16   7.1   3.9 | -10.3  13.5  195  33 17   6.1   3.4
 17500  -9.0  15.8  195  29 15   7.4   4.1 |  -9.4  15.1  195  31 16   7.1   3.9
 17000  -7.9  17.8  195  29 15   7.5   4.1 |  -8.2  17.2  195  31 16   7.5   4.1
 16500  -6.8  19.8  195  29 15   7.5   4.1 |  -6.5  20.3  200  30 15   7.5   4.1
 16000  -5.2  22.6  195  28 14   7.4   4.0 |  -5.4  22.3  200  30 15   7.4   4.1
 15500  -4.1  24.6  200  27 14   7.5   4.1 |  -4.2  24.4  200  29 15   7.2   3.9
 15000  -3.0  26.6  205  26 13   7.6   4.2 |  -3.2  26.2  200  28 15   6.8   3.7
 14500  -1.8  28.8  210  25 13   7.5   4.1 |  -2.2  28.0  205  27 14   6.9   3.8
 14000  -0.8  30.6  210  25 13   7.0   3.8 |  -1.1  30.0  205  26 14   7.7   4.2
 13500   0.2  32.4  215  24 12   7.0   3.8 |  -0.1  31.8  205  26 13   7.8   4.3
 13000   1.3  34.3  215  23 12   7.0   3.8 |   1.0  33.8  210  24 13   6.8   3.7
 12500   2.3  36.1  215  21 11   7.0   3.9 |   1.9  35.4  210  23 12   7.0   3.8
 12000   3.3  37.9  215  19 10   6.9   3.8 |   2.9  37.2  210  21 11   7.7   4.2
 11500   4.3  39.7  205  16  8   6.8   3.7 |   4.0  39.2  210  20 10   7.9   4.3
 11000   5.4  41.7  195  13  7   8.0   4.4 |   5.0  41.0  205  19 10   6.9   3.8
 10500   6.6  43.9  180  11  6   8.7   4.8 |   6.0  42.8  200  17  9   5.9   3.2
 10250   7.2  45.0  170  10  5   4.9   2.7 |   6.5  43.7  195  17  9  10.9   6.0
 10000   7.4  45.3  170   9  5   5.9   3.3 |   7.5  45.5  185  16  8  12.4   6.8
  9750   8.1  46.6  165   8  4  10.1   5.6 |   8.3  46.9  185  15  8   8.3   4.5
  9500   8.7  47.7  155   6  3  10.1   5.6 |   9.0  48.2  180  15  8   9.9   5.4
  9250   9.4  48.9  140   5  2   5.7   3.1 |   9.7  49.5  175  14  7   7.6   4.1
  9000   9.6  49.3  135   2  1   2.7   1.5 |  10.1  50.2  170  13  7   5.5   3.0
  8750   9.9  49.8  060   1  0   5.2   2.9 |  10.5  50.9  165  11  6   6.0   3.3
  8500  10.3  50.5  350   3  1   4.6   2.5 |  10.9  51.6  155  10  5   6.1   3.3
  8250  10.6  51.1  345   5  2   5.2   2.8 |  11.3  52.3  145   9  4   4.5   2.5
  8000  11.0  51.8  340   6  3   5.4   2.9 |  11.4  52.5  135   6  3   4.6   2.5
  7750  11.3  52.3  340   7  3   5.2   2.9 |  11.7  53.1  125   5  2   6.3   3.5
  7500  11.6  52.9  345   7  4   5.3   2.9 |  12.1  53.8  110   4  2   7.3   4.0
  7250  12.0  53.6  345   7  4   5.5   3.0 |  12.7  54.9  100   3  2   9.4   5.2
  7000  12.3  54.1  350   8  4   5.5   3.0 |  13.4  56.1  100   3  2  10.1   5.5
  6750  12.7  54.9  355   8  4   5.0   2.8 |  14.1  57.4  100   3  2   9.5   5.2
  6500  12.9  55.2  360   8  4   4.7   2.6 |  14.9  58.8  100   3  2   9.9   5.4
  6250  13.3  55.9  355   6  3   5.0   2.7 |  15.6  60.1  095   3  2  10.7   5.9
  6000  13.6  56.5  350   5  3   4.1   2.2 |  16.4  61.5  095   3  2   9.9   5.4
  5750  13.9  57.0  340   4  2   5.7   3.2 |  17.2  63.0  095   3  2  12.7   6.9
  5500  14.5  58.1  315   3  1  13.0   7.1 |  18.4  65.1  095   3  1  21.7  11.9

           09/29/2014 at 1500 MDT          |       09/29/2014 at 1800 MDT
                                           |
K index... +27.4  LI... -3.6               | K index... +31.2  LI... -1.8
CAPE... +538.1  CIN... -1.9                | CAPE... +305.7  CIN... -23.8
                                           |
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 -60.2 -76.4  225  31 16   2.3   1.3 | -57.9 -72.2  235  27 14   2.6   1.4
 45000 -56.4 -69.5  220  48 25   2.9   1.6 | -54.0 -65.2  220  38 19   1.9   1.0
 40000 -52.0 -61.6  220  76 39   3.0   1.7 | -51.2 -60.2  210  57 29   2.0   1.1
 38000 -50.6 -59.1  220  77 40   2.1   1.2 | -50.6 -59.1  205  62 32   0.6   0.4
 36000 -49.4 -56.9  215  77 40   2.1   1.2 | -50.3 -58.5  200  68 35   0.6   0.4
 34000 -46.7 -52.1  215  74 38   7.3   4.0 | -48.2 -54.8  195  68 35   7.7   4.2
 32000 -41.8 -43.2  210  66 34   7.3   4.0 | -43.1 -45.6  195  61 31   7.6   4.2
 30000 -36.6 -33.9  205  59 30   9.6   5.3 | -38.1 -36.6  195  50 26   9.1   5.0
 29000 -33.7 -28.7  200  56 29   9.6   5.3 | -35.3 -31.5  195  43 22   9.1   5.0
 28000 -30.9 -23.6  195  53 27   9.6   5.3 | -32.6 -26.7  195  36 18   9.1   5.0
 27000 -28.3 -18.9  195  53 27   7.7   4.2 | -30.1 -22.2  195  32 17   7.9   4.4
 26000 -26.1 -15.0  200  54 28   7.6   4.2 | -27.7 -17.9  195  33 17   7.9   4.4
 25000 -23.8 -10.8  205  55 28   7.6   4.2 | -25.4 -13.7  200  33 17   8.0   4.4
 24000 -21.7  -7.1  205  55 28   5.1   2.8 | -23.1  -9.6  200  34 17   7.1   3.9
 23000 -20.2  -4.4  210  53 27   5.3   2.9 | -20.9  -5.6  200  34 17   7.2   4.0
 22000 -18.6  -1.5  210  50 26   5.3   2.9 | -18.8  -1.8  200  34 17   7.2   4.0
 21000 -16.9   1.6  210  48 25   6.4   3.5 | -16.7   1.9  200  34 17   7.0   3.8
 20000 -15.0   5.0  210  46 24   6.4   3.5 | -14.7   5.5  200  33 17   7.0   3.8
 19500 -14.0   6.8  205  45 23   6.4   3.5 | -13.6   7.5  200  33 17   7.0   3.9
 19000 -13.0   8.6  205  44 23   6.3   3.4 | -12.6   9.3  195  33 17   7.1   3.9
 18500 -12.0  10.4  205  44 22   8.1   4.4 | -11.6  11.1  195  32 17   6.6   3.6
 18000 -10.8  12.6  205  43 22   7.9   4.3 | -10.7  12.7  190  31 16   6.6   3.6
 17500  -9.7  14.5  205  42 22   7.5   4.1 |  -9.7  14.5  190  30 15   6.5   3.5
 17000  -8.6  16.5  205  40 21   7.1   3.9 |  -8.8  16.2  185  30 15   6.2   3.4
 16500  -7.6  18.3  205  39 20   7.2   3.9 |  -7.9  17.8  185  30 15   6.2   3.4
 16000  -6.1  21.0  200  35 18   7.3   4.0 |  -7.0  19.4  180  30 16   6.1   3.4
 15500  -5.0  23.0  200  32 16   7.5   4.1 |  -5.7  21.7  175  31 16   6.2   3.4
 15000  -3.9  25.0  195  29 15   7.9   4.3 |  -4.7  23.5  175  31 16   6.8   3.7
 14500  -2.8  27.0  185  26 13   7.9   4.3 |  -3.8  25.2  175  31 16   6.7   3.7
 14000  -1.7  28.9  180  24 12   8.3   4.6 |  -2.7  27.1  175  30 16   7.7   4.2
 13500  -0.5  31.1  170  22 11   8.3   4.6 |  -1.7  28.9  180  28 14   7.8   4.3
 13000   0.7  33.3  160  21 11   8.9   4.9 |  -0.6  30.9  180  26 14   7.3   4.0
 12500   1.9  35.4  155  19 10   8.9   4.9 |   0.5  32.9  185  26 13   7.1   3.9
 12000   3.3  37.9  150  18  9   9.6   5.3 |   1.6  34.9  185  25 13   8.9   4.9
 11500   4.7  40.5  150  17  9   9.8   5.4 |   3.0  37.4  190  24 13   9.6   5.3
 11000   6.1  43.0  150  17  9   8.5   4.7 |   4.3  39.7  190  24 12   8.0   4.4
 10500   7.3  45.1  150  16  8   8.1   4.4 |   5.4  41.7  195  23 12   6.7   3.7
 10250   8.0  46.4  145  15  8  11.6   6.4 |   6.0  42.8  195  23 12   9.5   5.2
 10000   8.9  48.0  145  15  8  11.6   6.4 |   6.8  44.2  200  22 11  10.2   5.6
  9750   9.6  49.3  145  15  8   9.0   5.0 |   7.4  45.3  205  22 11   7.9   4.3
  9500  10.4  50.7  145  14  7   9.5   5.2 |   8.0  46.4  205  22 11   8.6   4.7
  9250  11.1  52.0  145  14  7  10.2   5.6 |   8.6  47.5  210  22 11   7.9   4.3
  9000  11.9  53.4  145  14  7  10.4   5.7 |   9.2  48.6  210  22 11   7.6   4.2
  8750  12.6  54.7  145  13  7   9.7   5.3 |   9.8  49.6  215  22 11   8.1   4.4
  8500  13.3  55.9  145  13  7   9.8   5.4 |  10.4  50.7  220  22 11   7.6   4.1
  8250  14.0  57.2  145  13  7  10.0   5.5 |  11.0  51.8  220  22 11   9.2   5.0
  8000  14.8  58.6  145  13  6  10.0   5.5 |  11.7  53.1  225  21 11   9.4   5.2
  7750  15.5  59.9  145  12  6   9.7   5.3 |  12.3  54.1  230  22 11   7.6   4.2
  7500  16.3  61.3  145  12  6   9.7   5.3 |  12.8  55.0  230  22 11   7.0   3.8
  7250  17.0  62.6  145  12  6  10.7   5.9 |  13.4  56.1  235  22 11   8.9   4.9
  7000  17.8  64.0  145  11  6  11.0   6.0 |  14.1  57.4  235  22 11  10.4   5.7
  6750  18.6  65.5  145  11  6   9.0   5.0 |  14.8  58.6  240  22 11   8.3   4.6
  6500  19.2  66.6  145  11  6   9.2   5.0 |  15.4  59.7  240  21 11   8.3   4.5
  6250  20.0  68.0  140  10  5  10.9   6.0 |  16.1  61.0  245  21 11  10.3   5.6
  6000  20.8  69.4  140  10  5  11.7   6.4 |  16.9  62.4  245  20 10  11.2   6.1
  5750  21.6  70.9  140   9  5   9.4   5.1 |  17.7  63.9  245  19 10   9.6   5.3
  5500  22.4  72.3  140   9  5  12.0   6.6 |  18.3  64.9  250  18  9   9.5   5.2
________________________________________________________________________________

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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