Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 211239
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0639 MDT Saturday, May 21, 2016

This forecast is for Saturday, May 21, 2016:

If the trigger temperature of 75.5 F/24.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1009 ft/min (5.1 m/s)
   Maximum height of thermals.................. 16638 ft MSL (11353 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1130 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................. 14249 ft MSL (8963 ft AGL)
Thermal soaring outlook for Sunday 05/22....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Poor - no change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 14613 ft MSL (9328 ft AGL)
Wave soaring outlook for Sunday 05/22.......... Poor

Remarks... Strong upper ridge over the western great plains and a large deep
           upper trough over the pacific northwest and northern great basin were
           producing a very warm and dry south-southwest flow aloft over
           colorado.

Sunrise/Sunset.................... 05:39:37 / 20:12:28 MDT
Total possible sunshine........... 14 hr 32 min 51 sec (872 min 51 sec)
Altitude of sun at 12:56:14 MDT... 70.60 degrees

Upper air data from rawinsonde observation taken on 05/21/2016 at 0600 MDT

Freezing level.................. 13940 ft MSL (8655 ft AGL)
Convective condensation level... 18057 ft MSL (12772 ft AGL)
Lifted condensation level....... 17539 ft MSL (12254 ft AGL)
Lifted index.................... -2.2
K index......................... +11.4

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -61.0 -77.8   255   39   20   4.4   2.4   95.8 204.4    38.2      M    M
 45000  -64.9 -84.8   245   49   25 -15.3  -8.4   64.9 148.8    21.8      M    M
 40000  -63.5 -82.3   225   13    7   6.6   3.6   42.8 109.0     8.9      M    M
 38000  -58.7 -73.7   200   22   11   8.5   4.7   41.3 106.3     8.1      M    M
 36000  -53.6 -64.5   210   25   13   9.0   5.0   40.3 104.5     7.6      M    M
 34000  -48.3 -54.9   220   28   14   8.5   4.7   39.5 103.1     7.2      M    M
 32000  -43.7 -46.7   215   28   14   1.7   0.9   37.8 100.0     6.2      M    M
 30000  -39.1 -38.4   205   21   11   9.4   5.2   36.2  97.2     5.1      M    M
 29000  -36.3 -33.3   210   20   10   9.3   5.1   36.1  97.0     5.1      M    M
 28000  -33.5 -28.3   210   20   10   9.4   5.1   35.9  96.5     5.0      M    M
 27000  -30.1 -22.2   205   20   11   8.0   4.4   35.5  95.9     4.8      M    M
 26000  -27.6 -17.7   200   21   11   8.1   4.5   34.9  94.7     4.3      M    M
 25000  -25.2 -13.4   200   21   11   8.1   4.5   34.3  93.8     3.9      M    M
 24000  -22.7  -8.9   195   22   12   8.7   4.8   33.8  92.8     3.5      M    M
 23000  -20.1  -4.2   190   23   12   8.7   4.8   33.5  92.2     3.3      M    M
 22000  -17.5   0.5   190   24   12   8.7   4.8   33.2  91.8     3.1      M    M
 21000  -14.9   5.2   195   25   13   8.7   4.8   32.8  91.0     2.8      M    M
 20000  -12.3   9.9   200   26   13   8.7   4.8   32.5  90.4     2.5      M    M
 19500  -11.0  12.2   200   27   14   8.7   4.8   32.2  90.0     2.4      M    M
 19000   -9.7  14.5   205   28   14   8.6   4.7   32.0  89.7     2.2      M    M
 18500   -8.4  16.9   205   28   15   8.7   4.8   31.8  89.2     2.0      M    M
 18000   -7.3  18.9   205   29   15   6.6   3.6   31.4  88.6     1.7      M    M
 17500   -6.3  20.7   205   29   15   6.9   3.8   30.9  87.6     1.2      M    M
 17000   -5.4  22.3   205   30   15   5.2   2.8   30.3  86.6     0.6      M    M
 16500   -4.7  23.5   210   28   14   5.1   2.8   29.5  85.1    -0.1   1004  5.1
 16000   -3.9  25.0   220   26   14   5.7   3.1   28.7  83.7    -0.8    967  4.9
 15500   -3.1  26.4   225   27   14   6.5   3.6   28.2  82.8    -1.4    926  4.7
 15000   -2.1  28.2   230   28   14   6.1   3.4   27.6  81.7    -1.9    883  4.5
 14500   -1.2  29.8   235   29   15   6.0   3.3   27.0  80.6    -2.5    842  4.3
 14000   -0.4  31.3   240   31   16   6.9   3.8   26.4  79.5    -3.2    803  4.1
 13500    1.4  34.5   240   32   17   8.8   4.8   26.1  79.0    -3.5    725  3.7
 13000    2.7  36.9   240   33   17   8.8   4.8   26.0  78.8    -3.6    671  3.4
 12500    4.0  39.2   245   31   16   8.8   4.8   25.8  78.5    -3.8    617  3.1
 12000    5.3  41.5   245   28   14   8.8   4.8   25.7  78.3    -4.0    564  2.9
 11500    6.6  43.9   245   22   11   8.8   4.8   25.5  78.0    -4.2    510  2.6
 11000    7.9  46.2   240   16    8   8.8   4.9   25.4  77.7    -4.4    456  2.3
 10500    9.2  48.6   230   13    7   8.9   4.9   25.2  77.4    -4.6    403  2.0
 10250    9.9  49.8   220   11    6   8.7   4.8   25.1  77.3    -4.7    376  1.9
 10000   10.5  50.9   215   10    5   8.5   4.7   25.1  77.1    -4.8    350  1.8
  9750   11.1  52.0   215    9    5   8.5   4.7   25.0  76.9    -4.9    323  1.6
  9500   11.8  53.2   210    8    4   8.5   4.7   24.9  76.8    -5.0    297  1.5
  9250   12.4  54.3   200    7    3   8.5   4.7   24.8  76.6    -5.1    271  1.4
  9000   13.0  55.4   195    6    3   8.5   4.7   24.7  76.5    -5.2    245  1.2
  8750   13.7  56.7   190    8    4   8.5   4.7   24.6  76.3    -5.3    218  1.1
  8500   14.3  57.7   190    9    5   8.5   4.7   24.5  76.1    -5.4    192  1.0
  8250   14.9  58.8   185   11    5   8.5   4.7   24.4  75.9    -5.5    166  0.8
  8000   15.6  60.1   185   12    6   8.6   4.7   24.3  75.8    -5.6    139  0.7
  7750   16.2  61.2   190   13    7   8.3   4.6   24.2  75.6    -5.8    113  0.6
  7500   16.8  62.2   195   15    8   9.2   5.1   24.1  75.4    -5.9     87  0.4
  7250   17.4  63.3   200   16    8   5.8   3.2   24.0  75.2    -6.0     61  0.3
  7000   17.7  63.9   205   18    9   3.6   2.0   23.5  74.4    -6.5     46  0.2
  6750   17.8  64.0   210   16    8  -4.5  -2.5   22.9  73.3    -7.1     36  0.2
  6500   16.5  61.7   210   15    8 -26.0 -14.3   21.0  69.9    -9.2     67  0.3
  6250   14.4  57.9   215   13    7 -13.5  -7.4   18.4  65.1   -12.0    123  0.6
  6000   14.3  57.7   220   12    6   3.5   1.9   17.6  63.8   -12.8    117  0.6
  5750   14.3  57.7   210    9    5  -0.6  -0.4   16.9  62.4   -13.7    111  0.6
  5500   14.2  57.6   190    6    3  -1.0  -0.6   16.2  61.1   -14.5    106  0.5

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

           05/21/2016 at 0900 MDT          |       05/21/2016 at 1200 MDT
                                           |
K index... +20.9  LI... -0.0               | K index... -8.9  LI... -0.6
CAPE... +1.5  CIN... -46.7                 | CAPE... +123.1  CIN... -45.8
                                           |
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 -62.6 -80.7  250  30 16  -1.9  -1.1 | -62.8 -81.0  250  37 19  -1.5  -0.8
 45000 -65.1 -85.2  250  45 23   2.3   1.2 | -64.7 -84.5  250  48 25   1.6   0.9
 40000 -61.9 -79.4  250  35 18   1.3   0.7 | -62.4 -80.3  255  48 25   0.7   0.4
 38000 -57.7 -71.9  245  31 16   7.7   4.2 | -58.0 -72.4  250  42 21   8.2   4.5
 36000 -53.1 -63.6  230  29 15   7.7   4.2 | -53.0 -63.4  245  35 18   8.2   4.5
 34000 -48.4 -55.1  225  27 14   8.1   4.5 | -48.0 -54.4  240  32 16   8.5   4.7
 32000 -43.5 -46.3  220  26 13   8.1   4.5 | -42.9 -45.2  240  31 16   8.5   4.7
 30000 -38.6 -37.5  215  26 13   8.3   4.5 | -37.1 -34.8  235  29 15   8.6   4.7
 29000 -35.5 -31.9  215  26 13   8.3   4.6 | -34.5 -30.1  230  28 15   8.6   4.7
 28000 -33.0 -27.4  210  26 13   8.3   4.5 | -31.9 -25.4  225  27 14   8.6   4.7
 27000 -30.4 -22.7  205  26 14   8.9   4.9 | -29.5 -21.1  220  27 14   8.2   4.5
 26000 -27.7 -17.9  205  27 14   8.9   4.9 | -27.0 -16.6  215  28 14   8.2   4.5
 25000 -25.1 -13.2  200  28 14   8.9   4.9 | -24.5 -12.1  205  29 15   8.1   4.5
 24000 -22.5  -8.5  200  29 15   7.9   4.3 | -22.3  -8.1  205  31 16   6.7   3.7
 23000 -20.2  -4.4  200  31 16   7.9   4.3 | -20.3  -4.5  205  31 16   6.7   3.7
 22000 -17.8  -0.0  195  33 17   7.9   4.3 | -18.3  -0.9  205  32 17   6.7   3.7
 21000 -15.9   3.4  195  32 17   5.3   2.9 | -16.2   2.8  205  33 17   7.6   4.2
 20000 -14.4   6.1  195  30 15   5.4   2.9 | -13.9   7.0  210  33 17   7.6   4.2
 19500 -13.6   7.5  195  29 15   5.5   3.0 | -12.7   9.1  210  33 17   7.6   4.2
 19000 -12.9   8.8  195  28 14   6.2   3.4 | -11.6  11.1  210  33 17   7.6   4.2
 18500 -11.8  10.8  190  27 14   8.2   4.5 | -10.5  13.1  210  34 18   7.4   4.1
 18000 -10.6  12.9  190  26 13   8.1   4.5 |  -9.4  15.1  205  35 18   7.4   4.1
 17500  -9.5  14.9  185  25 13   8.7   4.8 |  -8.3  17.1  205  36 18   7.3   4.0
 17000  -8.2  17.2  185  25 13   8.8   4.8 |  -7.2  19.0  200  36 18   7.3   4.0
 16500  -6.9  19.6  185  24 12   8.8   4.8 |  -6.1  21.0  195  36 19   7.6   4.2
 16000  -5.6  21.9  185  24 12   8.6   4.7 |  -4.8  23.4  195  35 18   8.4   4.6
 15500  -3.7  25.3  190  23 12   8.9   4.9 |  -2.9  26.8  195  34 17   8.1   4.4
 15000  -2.3  27.9  195  23 12   9.2   5.0 |  -1.8  28.8  200  33 17   7.8   4.3
 14500  -0.8  30.6  200  23 12   8.9   4.9 |  -0.6  30.9  205  31 16   7.6   4.1
 14000   0.4  32.7  210  23 12   7.8   4.3 |   0.4  32.7  205  30 16   6.2   3.4
 13500   1.6  34.9  215  24 12   7.9   4.3 |   1.3  34.3  210  29 15   6.6   3.6
 13000   2.7  36.9  220  23 12   7.3   4.0 |   2.2  36.0  205  28 15   7.3   4.0
 12500   3.8  38.8  225  22 11   7.3   4.0 |   3.2  37.8  205  27 14   7.3   4.0
 12000   4.9  40.8  225  21 11   7.9   4.4 |   4.3  39.7  200  26 13   8.6   4.7
 11500   6.0  42.8  225  19 10   8.0   4.4 |   5.5  41.9  200  24 13   8.7   4.8
 11000   7.1  44.8  225  17  9   7.1   3.9 |   6.7  44.1  195  23 12   8.1   4.5
 10500   8.1  46.6  220  14  7   6.0   3.3 |   7.8  46.0  190  20 10   7.9   4.3
 10250   8.6  47.5  215  13  6  11.7   6.4 |   8.4  47.1  190  19 10  10.6   5.8
 10000   9.7  49.5  215  11  6  13.0   7.1 |   9.3  48.7  185  17  9  11.2   6.1
  9750  10.4  50.7  215  11  5   8.2   4.5 |  10.0  50.0  180  17  9   9.2   5.1
  9500  11.1  52.0  210  10  5   9.9   5.4 |  10.7  51.3  180  16  8   9.8   5.4
  9250  11.8  53.2  210   9  5   8.1   4.4 |  11.4  52.5  180  15  8   9.6   5.3
  9000  12.3  54.1  215   9  5   7.8   4.3 |  12.1  53.8  175  14  7   9.8   5.4
  8750  13.0  55.4  220   8  4   9.0   5.0 |  12.8  55.0  175  14  7  10.1   5.5
  8500  13.6  56.5  225   8  4   8.7   4.8 |  13.6  56.5  170  13  7   9.9   5.4
  8250  14.3  57.7  230   7  4   8.5   4.7 |  14.3  57.7  170  13  7  10.6   5.8
  8000  14.9  58.8  250   7  3   7.6   4.2 |  15.1  59.2  170  12  6  10.4   5.7
  7750  15.4  59.7  265   7  3   7.2   3.9 |  15.8  60.4  165  11  6   9.4   5.1
  7500  15.9  60.6  275   7  4   6.5   3.6 |  16.5  61.7  165  11  6   9.6   5.3
  7250  16.3  61.3  285   7  4   4.8   2.6 |  17.2  63.0  165  10  5  10.3   5.6
  7000  16.6  61.9  295   7  4   3.5   1.9 |  18.0  64.4  165  10  5  10.5   5.8
  6750  16.8  62.2  305   7  4   2.5   1.4 |  18.8  65.8  160   9  5   9.6   5.3
  6500  16.9  62.4  315   7  4  -0.4  -0.2 |  19.5  67.1  160   9  5   9.9   5.4
  6250  16.7  62.1  315   6  3  -2.2  -1.2 |  20.3  68.5  160   9  4  11.0   6.0
  6000  16.5  61.7  320   3  2  -2.9  -1.6 |  21.1  70.0  160   8  4  10.8   5.9
  5750  16.2  61.2  320   1  1   1.7   0.9 |  21.9  71.4  160   8  4  11.4   6.3
  5500  16.8  62.2  000   0  0  15.6   8.6 |  22.9  73.2  155   8  4  18.5  10.2

           05/21/2016 at 1500 MDT          |       05/21/2016 at 1800 MDT
                                           |
K index... +8.6  LI... +1.2                | K index... +13.6  LI... +0.6
CAPE... 0.0  CIN... -0.7                   | CAPE... +20.4  CIN... -89.3
                                           |
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 -62.2 -80.0  250  30 15  -1.7  -0.9 | -61.0 -77.8  255  20 10  -1.8  -1.0
 45000 -64.4 -83.9  250  35 18   0.6   0.4 | -63.5 -82.3  245  23 12   0.0   0.0
 40000 -63.4 -82.1  255  53 27  -0.1  -0.0 | -63.4 -82.1  250  49 25  -1.0  -0.6
 38000 -58.5 -73.3  255  47 24   9.1   5.0 | -58.5 -73.3  245  50 26   9.3   5.1
 36000 -53.0 -63.4  255  39 20   9.1   5.0 | -52.9 -63.2  245  48 25   9.3   5.1
 34000 -47.7 -53.9  250  35 18   8.9   4.9 | -47.6 -53.7  240  48 24   8.6   4.7
 32000 -42.3 -44.1  240  36 18   8.9   4.9 | -42.5 -44.5  240  47 24   8.6   4.7
 30000 -36.4 -33.5  235  37 19   8.6   4.7 | -36.7 -34.1  240  44 23   8.6   4.7
 29000 -33.8 -28.8  240  38 20   8.6   4.7 | -34.1 -29.4  235  42 22   8.6   4.7
 28000 -31.2 -24.2  240  39 20   8.6   4.7 | -31.5 -24.7  235  40 21   8.6   4.7
 27000 -28.7 -19.7  240  37 19   8.3   4.5 | -28.9 -20.0  230  35 18   8.6   4.7
 26000 -26.2 -15.2  235  33 17   8.3   4.5 | -26.4 -15.5  225  30 15   8.6   4.7
 25000 -23.8 -10.8  230  29 15   8.2   4.5 | -23.8 -10.8  215  25 13   8.5   4.7
 24000 -21.6  -6.9  225  28 14   5.9   3.2 | -21.3  -6.3  210  24 12   8.0   4.4
 23000 -19.8  -3.6  220  29 15   5.9   3.2 | -18.9  -2.0  220  27 14   8.0   4.4
 22000 -18.1  -0.6  220  30 16   5.9   3.2 | -16.5   2.3  230  31 16   8.0   4.4
 21000 -16.0   3.2  220  31 16   8.0   4.4 | -14.4   6.1  230  33 17   6.6   3.6
 20000 -13.6   7.5  220  31 16   8.1   4.4 | -12.4   9.7  230  32 17   6.6   3.6
 19500 -12.4   9.7  225  31 16   8.1   4.4 | -11.4  11.5  235  32 17   6.6   3.6
 19000 -11.2  11.8  225  31 16   8.0   4.4 | -10.4  13.3  235  32 17   6.5   3.6
 18500 -10.0  14.0  225  30 16   7.9   4.3 |  -9.5  14.9  230  32 16   6.1   3.4
 18000  -8.8  16.2  225  30 15   7.9   4.3 |  -8.6  16.5  230  31 16   6.2   3.4
 17500  -7.6  18.3  220  29 15   8.1   4.4 |  -7.6  18.3  225  30 16   7.2   4.0
 17000  -6.4  20.5  220  29 15   8.1   4.5 |  -6.5  20.3  225  31 16   7.6   4.2
 16500  -5.2  22.6  220  28 14   7.7   4.2 |  -5.4  22.3  220  31 16   7.8   4.3
 16000  -3.7  25.3  215  26 14   6.6   3.6 |  -3.6  25.5  210  31 16   8.5   4.7
 15500  -2.8  27.0  210  25 13   6.6   3.6 |  -2.4  27.7  205  31 16   8.6   4.7
 15000  -1.8  28.8  200  24 12   6.8   3.7 |  -1.2  29.8  205  30 16   8.7   4.8
 14500  -0.9  30.4  195  23 12   7.3   4.0 |   0.1  32.2  200  30 15   8.8   4.8
 14000   0.3  32.5  190  22 12   9.4   5.1 |   1.4  34.5  200  30 15   9.3   5.1
 13500   1.6  34.9  190  22 11   9.2   5.1 |   2.8  37.0  195  29 15   9.3   5.1
 13000   3.0  37.4  190  22 11   9.9   5.5 |   4.2  39.6  195  29 15   9.6   5.3
 12500   4.5  40.1  190  22 11   9.9   5.4 |   5.6  42.1  195  30 15   9.6   5.3
 12000   5.9  42.6  190  22 11   9.5   5.2 |   7.0  44.6  190  30 15   9.4   5.1
 11500   7.4  45.3  190  22 11   9.6   5.3 |   8.4  47.1  190  30 15   9.4   5.2
 11000   8.7  47.7  190  21 11   8.9   4.9 |   9.8  49.6  190  30 15   8.5   4.6
 10500  10.1  50.2  190  21 11   9.4   5.2 |  11.0  51.8  185  30 15   8.8   4.8
 10250  10.8  51.4  190  21 11  11.9   6.5 |  11.7  53.1  185  30 15  11.3   6.2
 10000  11.8  53.2  190  21 11  11.2   6.2 |  12.6  54.7  185  30 15  10.7   5.9
  9750  12.5  54.5  190  21 11   9.6   5.2 |  13.3  55.9  185  29 15   9.1   5.0
  9500  13.3  55.9  190  21 11  10.1   5.6 |  14.0  57.2  185  29 15   9.3   5.1
  9250  14.0  57.2  190  21 11   9.5   5.2 |  14.6  58.3  185  29 15  10.0   5.5
  9000  14.7  58.5  190  21 11   9.5   5.2 |  15.4  59.7  185  29 15  10.0   5.5
  8750  15.4  59.7  190  21 11  10.0   5.5 |  16.1  61.0  185  28 15   9.3   5.1
  8500  16.1  61.0  190  21 11   9.5   5.2 |  16.8  62.2  180  28 14   9.0   5.0
  8250  16.9  62.4  190  21 11  11.0   6.0 |  17.5  63.5  180  28 14  10.9   6.0
  8000  17.7  63.9  190  20 10  10.7   5.9 |  18.4  65.1  180  27 14  10.9   6.0
  7750  18.4  65.1  190  20 10   9.0   5.0 |  19.1  66.4  180  27 14   9.0   4.9
  7500  19.1  66.4  190  20 10   9.3   5.1 |  19.8  67.6  180  27 14   9.3   5.1
  7250  19.9  67.8  190  20 10  10.6   5.8 |  20.4  68.7  180  27 14   9.8   5.4
  7000  20.7  69.3  190  20 10  11.3   6.2 |  21.2  70.2  180  26 13  10.2   5.6
  6750  21.5  70.7  190  19 10   9.8   5.4 |  21.9  71.4  180  26 13   9.3   5.1
  6500  22.2  72.0  190  19 10   9.8   5.4 |  22.6  72.7  180  25 13   9.1   5.0
  6250  23.0  73.4  190  19 10  10.6   5.8 |  23.3  73.9  180  24 12  10.1   5.5
  6000  23.8  74.8  190  18  9  11.2   6.2 |  24.1  75.4  180  23 12  10.7   5.9
  5750  24.6  76.3  190  18  9   9.6   5.3 |  24.9  76.8  180  21 11  10.2   5.6
  5500  25.3  77.5  190  17  9  13.4   7.4 |  25.6  78.1  180  18  9  10.6   5.8
________________________________________________________________________________

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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