Soaring Guidance
Issued by NWS Denver/Boulder, CO

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249
UXUS97 KBOU 270040
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1839 MDT Thursday, May 26, 2016

This forecast is for Friday, May 27, 2016:

If the trigger temperature of 56.2 F/13.4 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 225 ft/min (1.1 m/s)
   Maximum height of thermals.................. 11175 ft MSL (5868 ft AGL)

Forecast maximum temperature................... 61.0 F/16.6 C
Time of trigger temperature.................... 1300 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8806 ft MSL (3499 ft AGL)
Thermal soaring outlook for Saturday 05/28..... 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....................... 14397 ft MSL (9090 ft AGL)
Wave soaring outlook for Saturday 05/28........ Poor

Remarks... None

Sunrise/Sunset.................... 05:35:46 / 20:17:30 MDT
Total possible sunshine........... 14 hr 41 min 43 sec (881 min 43 sec)
Altitude of sun at 12:56:50 MDT... 71.67 degrees

Upper air data from numerical model forecast valid on 05/27/2016 at 0600 MDT

Freezing level.................. 10098 ft MSL (4791 ft AGL)
Convective condensation level... 9374 ft MSL (4067 ft AGL)
Lifted condensation level....... 10426 ft MSL (5119 ft AGL)
Lifted index.................... -0.2
K index......................... +25.7

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  -53.9 -65.0   200   25   13   0.9   0.5      M     M       M      M    M
 45000  -52.6 -62.7   210   23   12  -0.6  -0.4      M     M       M      M    M
 40000  -55.0 -67.0   185   17    9  -1.5  -0.8      M     M       M      M    M
 38000  -54.5 -66.1   175   16    8   2.4   1.3      M     M       M      M    M
 36000  -53.1 -63.6   175   15    8   2.4   1.3      M     M       M      M    M
 34000  -51.2 -60.2   170   12    6   6.6   3.6      M     M       M      M    M
 32000  -47.4 -53.3   105    6    3   6.4   3.5      M     M       M      M    M
 30000  -43.1 -45.6   050   11    6  10.2   5.6   32.9  91.2    12.6      M    M
 29000  -39.4 -38.9   050   13    7  10.1   5.5   33.0  91.3    12.8      M    M
 28000  -36.3 -33.3   055   15    8  10.1   5.5   33.1  91.7    13.1      M    M
 27000  -33.4 -28.1   050   17    9   7.6   4.2   33.3  91.9    13.4      M    M
 26000  -31.4 -24.5   030   16    8   6.9   3.8   32.0  89.7    12.6      M    M
 25000  -29.4 -20.9   010   17    9   6.9   3.8   31.0  87.7    11.8      M    M
 24000  -27.3 -17.1   355   19   10   7.3   4.0   30.0  86.0    11.2      M    M
 23000  -24.9 -12.8   005   22   11   8.2   4.5   29.3  84.8    10.7      M    M
 22000  -22.4  -8.3   015   25   13   8.2   4.5   28.8  83.8    10.4      M    M
 21000  -20.0  -4.0   025   29   15   6.9   3.8   28.3  82.9    10.1      M    M
 20000  -18.2  -0.8   025   29   15   6.2   3.4   26.9  80.5     9.0      M    M
 19500  -17.3   0.9   020   29   15   6.2   3.4   26.3  79.4     8.5      M    M
 19000  -16.4   2.5   020   29   15   6.3   3.4   25.7  78.3     8.1      M    M
 18500  -15.5   4.1   020   28   15   6.2   3.4   25.2  77.4     7.6      M    M
 18000  -14.6   5.7   020   28   15   6.0   3.3   24.5  76.2     7.1      M    M
 17500  -13.7   7.3   015   28   15   6.0   3.3   23.9  75.0     6.5      M    M
 17000  -12.8   9.0   010   28   15   6.3   3.5   23.3  73.9     6.0      M    M
 16500  -11.9  10.6   010   29   15   6.4   3.5   22.7  72.9     5.5      M    M
 16000  -11.0  12.2   005   29   15   6.9   3.8   22.2  71.9     5.0      M    M
 15500   -9.4  15.1   010   30   15   7.4   4.1   21.5  70.8     4.4      M    M
 15000   -8.4  16.9   010   30   16   7.1   3.9   21.1  70.0     4.0      M    M
 14500   -7.3  18.9   010   31   16   7.0   3.9   20.7  69.2     3.6      M    M
 14000   -6.3  20.7   015   32   16   6.9   3.8   20.2  68.4     3.1      M    M
 13500   -5.4  22.3   010   33   17   6.8   3.7   19.7  67.5     2.7      M    M
 13000   -4.4  24.1   010   35   18   6.8   3.7   19.3  66.7     2.2      M    M
 12500   -3.4  25.9   010   36   18   6.8   3.7   18.8  65.8     1.7      M    M
 12000   -2.4  27.7   010   37   19   6.2   3.4   18.3  65.0     1.3      M    M
 11500   -1.8  28.8   010   37   19   4.0   2.2   17.5  63.5     0.5      M    M
 11000   -1.2  29.8   010   37   19   4.2   2.3   16.6  61.9    -0.4    411  2.1
 10500   -0.5  31.1   010   36   19   4.3   2.4   15.8  60.4    -1.2    377  1.9
 10250   -0.2  31.6   005   36   18   5.0   2.8   15.3  59.6    -1.6    360  1.8
 10000    0.2  32.4   005   35   18   6.9   3.8   15.1  59.1    -1.9    340  1.7
  9750    0.7  33.3   005   35   18   7.2   3.9   14.9  58.7    -2.1    317  1.6
  9500    1.2  34.2   005   34   18   6.8   3.7   14.6  58.3    -2.4    295  1.5
  9250    1.7  35.1   005   34   17   6.7   3.6   14.4  57.9    -2.6    273  1.4
  9000    2.2  36.0   005   33   17   7.6   4.2   14.2  57.5    -2.9    251  1.3
  8750    2.8  37.0   005   32   16   7.4   4.1   14.0  57.3    -3.0    226  1.2
  8500    3.2  37.8   360   31   16   6.2   3.4   13.8  56.8    -3.3    205  1.0
  8250    3.7  38.7   360   30   16   6.8   3.7   13.5  56.4    -3.6    183  0.9
  8000    4.3  39.7   360   29   15   8.7   4.8   13.4  56.1    -3.7    159  0.8
  7750    4.9  40.8   360   29   15   8.5   4.7   13.3  56.0    -3.8    132  0.7
  7500    5.5  41.9   360   28   15   6.9   3.8   13.1  55.6    -4.0    108  0.5
  7250    6.1  43.0   360   28   14   8.0   4.4   13.0  55.3    -4.2     84  0.4
  7000    6.7  44.1   360   27   14   9.3   5.1   12.9  55.2    -4.3     57  0.3
  6750    7.4  45.3   360   27   14   8.2   4.5   12.8  55.1    -4.3     29  0.1
  6500    7.9  46.2   355   26   13   7.2   4.0   12.6  54.8    -4.5      5  0.0
  6250    8.5  47.3   355   25   13   5.8   3.2   12.4  54.4    -4.7      M    M
  6000    8.8  47.8   350   22   11   4.3   2.4   12.1  53.7    -5.1      M    M
  5750    9.1  48.4   345   19   10   5.4   2.9   11.7  53.0    -5.6      M    M
  5500    9.5  49.1   335   14    7   5.7   3.1   11.4  52.5    -5.9      M    M

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

           05/27/2016 at 0900 MDT          |       05/27/2016 at 1200 MDT
                                           |
K index... +25.3  LI... -0.4               | K index... +22.6  LI... -0.2
CAPE... +80.0  CIN... -1.9                 | CAPE... +85.8  CIN... -10.0
                                           |
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 -54.1 -65.4  200  23 12   1.0   0.6 | -54.5 -66.1  195  21 11   0.9   0.5
 45000 -52.6 -62.7  210  20 10  -0.9  -0.5 | -53.4 -64.1  210  16  8  -1.5  -0.8
 40000 -55.6 -68.1  180  13  7  -1.9  -1.1 | -55.4 -67.7  195  14  7  -1.4  -0.7
 38000 -55.2 -67.4  165  10  5   2.4   1.3 | -55.0 -67.0  180  11  6   1.9   1.1
 36000 -53.7 -64.7  140   7  4   2.4   1.3 | -53.9 -65.0  160   9  4   1.9   1.1
 34000 -51.7 -61.1  090   7  3   7.4   4.1 | -52.0 -61.6  125   7  4   7.3   4.0
 32000 -47.4 -53.3  045  13  6   7.2   4.0 | -47.7 -53.9  080   8  4   7.3   4.0
 30000 -42.8 -45.0  035  20 10   9.3   5.1 | -42.4 -44.3  055  13  7   9.5   5.2
 29000 -39.3 -38.7  040  21 11   9.3   5.1 | -39.5 -39.1  045  15  8   9.5   5.2
 28000 -36.5 -33.7  040  22 11   9.3   5.1 | -36.7 -34.1  035  18  9   9.5   5.2
 27000 -33.8 -28.8  045  23 12   7.9   4.3 | -34.0 -29.2  030  21 11   7.9   4.4
 26000 -31.5 -24.7  035  24 12   7.6   4.2 | -31.7 -25.1  025  22 11   7.8   4.3
 25000 -29.3 -20.7  030  25 13   7.6   4.2 | -29.3 -20.7  020  23 12   7.8   4.3
 24000 -27.0 -16.6  025  27 14   7.4   4.1 | -27.0 -16.6  010  25 13   7.8   4.3
 23000 -24.9 -12.8  025  27 14   7.1   3.9 | -24.7 -12.5  010  27 14   7.8   4.3
 22000 -22.8  -9.0  020  28 14   7.1   3.9 | -22.4  -8.3  010  28 15   7.8   4.3
 21000 -20.7  -5.3  020  28 15   7.3   4.0 | -20.2  -4.4  010  30 15   7.5   4.1
 20000 -18.5  -1.3  020  30 15   7.4   4.1 | -18.0  -0.4  010  31 16   7.4   4.1
 19500 -17.5   0.5  020  30 16   7.4   4.1 | -16.9   1.6  010  32 16   7.4   4.1
 19000 -16.4   2.5  015  31 16   7.4   4.1 | -15.8   3.6  015  32 17   7.4   4.1
 18500 -15.3   4.5  015  31 16   7.1   3.9 | -14.7   5.5  015  33 17   7.4   4.1
 18000 -14.3   6.3  015  32 17   6.6   3.6 | -13.7   7.3  010  33 17   7.4   4.1
 17500 -13.4   7.9  015  33 17   6.5   3.6 | -12.6   9.3  010  33 17   7.6   4.2
 17000 -12.4   9.7  015  34 17   7.2   3.9 | -11.6  11.1  010  34 17   5.7   3.1
 16500 -11.3  11.7  015  34 18   7.1   3.9 | -10.7  12.7  005  34 18   5.9   3.2
 16000 -10.3  13.5  015  35 18   6.5   3.6 |  -9.9  14.2  005  34 18   5.3   2.9
 15500  -9.0  15.8  015  36 19   6.0   3.3 |  -8.8  16.2  360  34 18   4.8   2.7
 15000  -8.2  17.2  015  37 19   5.7   3.2 |  -8.0  17.6  360  34 18   5.6   3.1
 14500  -7.3  18.9  015  37 19   5.7   3.1 |  -7.2  19.0  360  35 18   5.7   3.1
 14000  -6.5  20.3  010  38 20   5.8   3.2 |  -6.4  20.5  355  35 18   5.8   3.2
 13500  -5.7  21.7  010  38 20   5.8   3.2 |  -5.5  22.1  355  35 18   5.9   3.2
 13000  -4.8  23.4  010  38 20   5.8   3.2 |  -4.7  23.5  355  36 18   5.9   3.2
 12500  -4.0  24.8  010  38 20   5.7   3.1 |  -3.8  25.2  360  36 18   5.8   3.2
 12000  -3.2  26.2  010  38 20   5.8   3.2 |  -3.0  26.6  360  36 18   6.0   3.3
 11500  -2.3  27.9  010  38 19   6.0   3.3 |  -2.1  28.2  360  36 19   6.1   3.4
 11000  -1.5  29.3  010  37 19   5.9   3.3 |  -1.2  29.8  360  36 19   5.8   3.2
 10500  -0.6  30.9  010  37 19   5.5   3.0 |  -0.4  31.3  005  36 19   5.1   2.8
 10250  -0.2  31.6  010  37 19   6.7   3.7 |  -0.1  31.8  005  36 18   5.8   3.2
 10000   0.3  32.5  010  36 19   9.1   5.0 |   0.4  32.7  005  36 18   7.5   4.1
  9750   1.0  33.8  010  36 18   9.3   5.1 |   1.0  33.8  005  35 18   8.1   4.4
  9500   1.7  35.1  010  35 18   8.9   4.9 |   1.6  34.9  005  34 17   7.9   4.3
  9250   2.3  36.1  005  34 18   9.2   5.0 |   2.1  35.8  010  33 17   7.9   4.3
  9000   3.0  37.4  005  34 17   8.5   4.7 |   2.7  36.9  010  31 16   8.3   4.5
  8750   3.5  38.3  005  33 17   7.7   4.2 |   3.3  37.9  010  29 15   8.7   4.8
  8500   4.1  39.4  005  33 17   7.6   4.2 |   3.9  39.0  005  28 14   8.6   4.7
  8250   4.6  40.3  005  32 17   7.9   4.4 |   4.5  40.1  005  26 14   9.0   4.9
  8000   5.2  41.4  005  32 16   8.6   4.7 |   5.2  41.4  005  25 13   9.7   5.3
  7750   5.8  42.4  005  32 16   7.4   4.1 |   5.9  42.6  005  24 13   9.5   5.2
  7500   6.3  43.3  005  32 16   6.5   3.6 |   6.5  43.7  005  24 12   8.9   4.9
  7250   6.8  44.2  005  32 16   6.6   3.6 |   7.2  45.0  005  23 12  10.1   5.5
  7000   7.3  45.1  360  30 16   6.3   3.4 |   8.0  46.4  005  23 12  11.4   6.3
  6750   7.7  45.9  355  29 15   5.2   2.8 |   8.8  47.8  005  22 12   9.8   5.4
  6500   8.1  46.6  355  26 13   4.5   2.4 |   9.5  49.1  005  22 11   9.1   5.0
  6250   8.5  47.3  350  23 12   7.9   4.3 |  10.2  50.4  005  21 11  10.6   5.8
  6000   9.2  48.6  345  20 10  10.2   5.6 |  11.1  52.0  005  20 11  11.7   6.4
  5750   9.9  49.8  345  17  9   9.3   5.1 |  11.9  53.4  010  19 10   9.8   5.4
  5500  10.6  51.1  345  15  8  11.3   6.2 |  12.6  54.7  010  18  9  12.0   6.6

           05/27/2016 at 1500 MDT          |       05/27/2016 at 1800 MDT
                                           |
K index... +18.1  LI... -0.9               | K index... +25.4  LI... -1.1
CAPE... +203.9  CIN... -5.9                | CAPE... +208.4  CIN... M
                                           |
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 -54.7 -66.5  190  27 14   1.0   0.5 | -54.4 -65.9  205  25 13  -0.2  -0.1
 45000 -53.4 -64.1  200  17  9  -0.7  -0.4 | -54.8 -66.6  205  16  8  -1.2  -0.7
 40000 -54.3 -65.7  225  17  9  -0.6  -0.3 | -56.5 -69.7  255  12  6  -1.2  -0.6
 38000 -54.2 -65.6  230  14  7   0.6   0.3 | -56.1 -69.0  270  13  7   2.0   1.1
 36000 -53.9 -65.0  240   9  5   0.6   0.3 | -54.8 -66.6  280  14  7   2.0   1.1
 34000 -52.5 -62.5  260   5  3   7.6   4.2 | -52.6 -62.7  290  16  8   8.3   4.6
 32000 -47.9 -54.2  285   6  3   7.7   4.2 | -47.5 -53.5  300  17  9   8.5   4.7
 30000 -42.3 -44.1  310   7  4   9.9   5.4 | -41.6 -42.9  310  18  9   9.3   5.1
 29000 -39.4 -38.9  330   7  4   9.9   5.4 | -38.8 -37.8  305  16  8   9.3   5.1
 28000 -36.4 -33.5  345   8  4   9.9   5.4 | -36.1 -33.0  305  15  8   9.3   5.1
 27000 -33.6 -28.5  360  10  5   7.8   4.3 | -33.4 -28.1  305  14  7   8.3   4.5
 26000 -31.2 -24.2  005  11  6   7.8   4.3 | -30.9 -23.6  305  15  8   8.4   4.6
 25000 -28.9 -20.0  010  13  7   7.9   4.3 | -28.4 -19.1  305  15  8   8.4   4.6
 24000 -26.6 -15.9  015  15  8   7.8   4.3 | -25.9 -14.6  305  16  8   7.7   4.2
 23000 -24.3 -11.7  005  16  8   7.8   4.3 | -23.7 -10.7  310  17  9   7.5   4.1
 22000 -21.9  -7.4  360  16  8   7.8   4.3 | -21.5  -6.7  310  19 10   7.5   4.1
 21000 -19.6  -3.3  355  17  9   7.3   4.0 | -19.3  -2.7  310  20 10   7.2   4.0
 20000 -17.5   0.5  350  19 10   7.3   4.0 | -17.1   1.2  320  21 11   7.3   4.0
 19500 -16.4   2.5  345  20 10   7.3   4.0 | -16.1   3.0  320  21 11   7.3   4.0
 19000 -15.4   4.3  345  21 11   7.3   4.0 | -15.0   5.0  325  21 11   7.3   4.0
 18500 -14.3   6.3  345  22 11   7.0   3.8 | -14.0   6.8  325  22 11   7.0   3.8
 18000 -13.3   8.1  345  23 12   6.7   3.7 | -13.0   8.6  330  22 12   6.8   3.8
 17500 -12.4   9.7  345  24 12   6.7   3.7 | -12.0  10.4  335  23 12   6.9   3.8
 17000 -11.4  11.5  340  25 13   6.2   3.4 | -11.0  12.2  335  23 12   7.2   4.0
 16500 -10.4  13.3  340  26 14   6.3   3.5 |  -9.9  14.2  340  24 12   7.3   4.0
 16000  -9.0  15.8  340  28 14   5.8   3.2 |  -8.5  16.7  345  25 13   5.5   3.0
 15500  -8.1  17.4  345  29 15   5.8   3.2 |  -7.7  18.1  350  26 13   5.6   3.1
 15000  -7.2  19.0  345  30 15   6.3   3.4 |  -6.9  19.6  355  27 14   6.0   3.3
 14500  -6.3  20.7  345  31 16   6.3   3.4 |  -6.0  21.2  360  28 14   6.0   3.3
 14000  -5.4  22.3  350  32 17   6.3   3.5 |  -5.1  22.8  360  28 15   5.8   3.2
 13500  -4.5  23.9  350  33 17   6.4   3.5 |  -4.3  24.3  005  28 14   5.7   3.1
 13000  -3.6  25.5  355  34 17   6.2   3.4 |  -3.5  25.7  005  28 14   6.0   3.3
 12500  -2.7  27.1  355  34 18   6.0   3.3 |  -2.5  27.5  005  25 13   6.3   3.4
 12000  -1.9  28.6  360  35 18   5.1   2.8 |  -1.6  29.1  010  23 12   6.1   3.3
 11500  -1.4  29.5  005  32 16   4.0   2.2 |  -0.8  30.6  005  19 10   5.9   3.2
 11000  -0.9  30.4  005  28 14   5.1   2.8 |   0.0  32.0  360  15  8   6.1   3.3
 10500   0.0  32.0  010  24 12   6.2   3.4 |   0.9  33.6  360  13  7   5.8   3.2
 10250   0.5  32.9  010  22 11   8.4   4.6 |   1.4  34.5  355  13  6   8.5   4.7
 10000   1.1  34.0  010  20 10  10.1   5.5 |   2.1  35.8  355  11  6   8.8   4.8
  9750   1.8  35.2  015  19 10   9.1   5.0 |   2.6  36.7  360  10  5   6.4   3.5
  9500   2.5  36.5  015  18  9   9.4   5.1 |   3.0  37.4  360   9  4   6.8   3.7
  9250   3.1  37.6  020  17  9   9.3   5.1 |   3.5  38.3  005   7  4   7.9   4.3
  9000   3.8  38.8  020  16  8   9.6   5.3 |   4.1  39.4  015   6  3   9.5   5.2
  8750   4.5  40.1  025  16  8   9.9   5.4 |   4.8  40.6  015   6  3   9.3   5.1
  8500   5.2  41.4  025  15  8   9.7   5.3 |   5.5  41.9  020   6  3   9.0   4.9
  8250   6.0  42.8  025  15  8  10.2   5.6 |   6.2  43.2  025   6  3  10.3   5.6
  8000   6.7  44.1  030  15  8  10.7   5.9 |   7.0  44.6  030   5  3  11.5   6.3
  7750   7.5  45.5  030  15  8  10.1   5.5 |   7.8  46.0  030   6  3   9.8   5.4
  7500   8.2  46.8  030  15  8   9.5   5.2 |   8.4  47.1  030   6  3   8.7   4.8
  7250   9.0  48.2  030  15  8  10.3   5.7 |   9.1  48.4  035   6  3   9.8   5.4
  7000   9.8  49.6  030  15  7  11.0   6.1 |   9.9  49.8  035   6  3  10.6   5.8
  6750  10.6  51.1  030  14  7   9.6   5.3 |  10.7  51.3  035   6  3   9.8   5.4
  6500  11.2  52.2  030  14  7   9.1   5.0 |  11.4  52.5  040   6  3   9.6   5.3
  6250  12.0  53.6  030  14  7  10.9   6.0 |  12.1  53.8  040   6  3  10.3   5.7
  6000  12.8  55.0  035  14  7  12.2   6.7 |  12.9  55.2  040   5  3  10.9   6.0
  5750  13.7  56.7  035  13  7  10.0   5.5 |  13.7  56.7  040   5  3   9.5   5.2
  5500  14.5  58.1  035  13  7  14.7   8.1 |  14.4  57.9  045   5  3  11.1   6.1
________________________________________________________________________________

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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