Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 261307
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0707 MDT Friday, June 26, 2015

This forecast is for Friday, June 26, 2015:

If the trigger temperature of 72.0 F/22.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 456 ft/min (2.3 m/s)
   Maximum height of thermals.................. 11850 ft MSL (6565 ft AGL)

Forecast maximum temperature................... 80.0 F/27.1 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10131 ft MSL (4846 ft AGL)
Thermal soaring outlook for Saturday 06/27..... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 12895 ft MSL (7610 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 19523 ft MSL (14238 ft AGL)
Wave soaring outlook for Saturday 06/27........ Poor

Remarks... None

Sunrise/Sunset.................... 05:33:08 / 20:31:28 MDT
Total possible sunshine........... 14 hr 58 min 20 sec (898 min 20 sec)
Altitude of sun at 13:02:22 MDT... 73.55 degrees

Upper air data from rawinsonde observation taken on 06/26/2015 at 0600 MDT

Freezing level.................. 15436 ft MSL (10151 ft AGL)
Convective condensation level... 11605 ft MSL (6320 ft AGL)
Lifted condensation level....... 11792 ft MSL (6507 ft AGL)
Lifted index.................... -2.2
K index......................... +25.1

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  -66.2 -87.2   330   39   20 -12.3  -6.7   82.7 180.9    32.6      M    M
 45000  -65.8 -86.4   310   26   13  -3.6  -2.0   59.2 138.6    20.3      M    M
 40000  -53.2 -63.8   320   24   12   7.8   4.3   54.9 130.8    18.9      M    M
 38000  -48.6 -55.5   320   28   14   7.8   4.3   53.1 127.6    18.2      M    M
 36000  -43.9 -47.0   325   34   17   7.7   4.2   51.4 124.5    17.5      M    M
 34000  -38.9 -38.0   320   35   18   9.0   4.9   50.3 122.5    17.1      M    M
 32000  -33.5 -28.3   325   37   19   9.0   4.9   49.8 121.6    17.2      M    M
 30000  -28.6 -19.5   325   39   20   8.1   4.4   48.6 119.5    16.7      M    M
 29000  -26.2 -15.2   330   41   21   8.1   4.4   47.8 118.1    16.3      M    M
 28000  -23.8 -10.8   335   43   22   8.1   4.4   47.1 116.8    15.9      M    M
 27000  -21.3  -6.3   340   46   24   3.0   1.6   45.7 114.3    15.1      M    M
 26000  -19.3  -2.7   340   45   23   7.7   4.2   44.6 112.2    14.3      M    M
 25000  -17.0   1.4   345   44   23   6.4   3.5   43.8 110.8    13.8      M    M
 24000  -15.4   4.3   340   40   21   5.5   3.0   42.2 108.0    12.7      M    M
 23000  -13.4   7.9   335   37   19   8.6   4.7   41.1 106.0    11.9      M    M
 22000  -11.3  11.7   330   34   18   2.3   1.3   40.1 104.2    11.2      M    M
 21000  -10.8  12.6   325   32   16  -6.0  -3.3   37.3  99.2     8.9      M    M
 20000  -10.3  13.5   315   30   15   4.7   2.6   34.6  94.3     6.5      M    M
 19500   -9.4  15.1   305   33   17   8.6   4.7   34.0  93.2     6.0      M    M
 19000   -8.2  17.2   305   33   17   8.5   4.7   33.8  92.9     5.8      M    M
 18500   -6.9  19.6   305   31   16   9.0   4.9   33.6  92.5     5.7      M    M
 18000   -5.6  21.9   310   29   15   9.2   5.0   33.5  92.3     5.6      M    M
 17500   -4.4  24.1   310   27   14   5.3   2.9   33.2  91.8     5.3      M    M
 17000   -3.5  25.7   310   26   13   8.6   4.7   32.7  90.8     4.8      M    M
 16500   -2.3  27.9   315   24   12   8.3   4.6   32.4  90.3     4.6      M    M
 16000   -1.1  30.0   315   22   11   6.7   3.7   32.1  89.8     4.3      M    M
 15500   -0.3  31.5   315   21   11   6.7   3.7   31.5  88.7     3.7      M    M
 15000    0.8  33.4   310   20   10   8.9   4.9   31.2  88.2     3.4      M    M
 14500    2.1  35.8   310   19   10   8.8   4.8   31.1  87.9     3.2      M    M
 14000    3.4  38.1   305   18    9   8.8   4.8   30.9  87.7     3.1      M    M
 13500    5.3  41.5   315   16    8   7.7   4.2   30.7  87.3     2.8      M    M
 13000    5.8  42.4   325   15    8   2.8   1.5   29.8  85.7     1.9      M    M
 12500    6.2  43.2   340   14    7   4.0   2.2   28.8  83.8     0.8      M    M
 12000    6.9  44.4   350   13    7   5.6   3.1   28.0  82.5     0.1      M    M
 11500    7.7  45.9   360   11    5   5.2   2.9   27.4  81.3    -0.6    422  2.1
 11000    8.2  46.8   020    8    4   4.7   2.6   26.6  79.8    -1.5    391  2.0
 10500    9.1  48.4   040    7    4   5.8   3.2   26.0  78.8    -2.1    350  1.8
 10250    9.2  48.6   040    6    3  -4.0  -2.2   25.4  77.7    -2.7    340  1.7
 10000    8.8  47.8   045    5    3   0.8   0.4   24.2  75.6    -3.8    344  1.7
  9750    9.4  48.9   045    4    2   9.7   5.3   24.1  75.4    -4.0    320  1.6
  9500   10.0  50.0   050    3    2   7.3   4.0   23.9  75.1    -4.2    296  1.5
  9250   10.5  50.9   055    3    1   8.0   4.4   23.8  74.9    -4.3    271  1.4
  9000   11.1  52.0   055    2    1   7.8   4.3   23.7  74.6    -4.5    247  1.3
  8750   11.7  53.1   355    2    1   7.9   4.3   23.5  74.3    -4.7    223  1.1
  8500   12.2  54.0   330    4    2   7.8   4.3   23.4  74.1    -4.8    198  1.0
  8250   12.8  55.0   320    5    3   8.2   4.5   23.2  73.8    -5.0    174  0.9
  8000   13.4  56.1   315    7    4   6.5   3.6   23.1  73.6    -5.2    150  0.8
  7750   13.7  56.7   315    8    4   2.5   1.4   22.7  72.8    -5.6    133  0.7
  7500   13.8  56.8   315    8    4   1.6   0.9   22.1  71.7    -6.2    122  0.6
  7250   13.9  57.0   315    9    4   1.3   0.7   21.4  70.6    -6.9    112  0.6
  7000   14.0  57.2   315    9    5   3.4   1.9   20.8  69.5    -7.5    101  0.5
  6750   14.3  57.7   315    8    4   5.8   3.2   20.5  68.9    -7.9     84  0.4
  6500   14.7  58.5   310    6    3   5.3   2.9   20.2  68.3    -8.3     66  0.3
  6250   15.0  59.0   305    5    3   5.5   3.0   19.9  67.7    -8.7     48  0.2
  6000   15.4  59.7   295    4    2   5.4   3.0   19.5  67.2    -9.1     31  0.2
  5750   15.7  60.3   295    3    1   5.8   3.2   19.2  66.6    -9.5     13  0.1
  5500   16.0  60.8   295    1    1   4.6   2.5   18.9  66.0    -9.9      M    M

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

           06/26/2015 at 0900 MDT          |       06/26/2015 at 1200 MDT
                                           |
K index... +26.7  LI... -2.3               | K index... +24.0  LI... -4.0
CAPE... +370.7  CIN... -14.0               | CAPE... +1098.8  CIN... -0.6
                                           |
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 -65.3 -85.5  325  20 10   0.3   0.2 | -65.3 -85.5  310  23 12  -0.1  -0.1
 45000 -62.5 -80.5  325  31 16   5.4   3.0 | -62.8 -81.0  315  35 18   5.7   3.1
 40000 -53.2 -63.8  335  38 20   8.3   4.6 | -53.2 -63.8  330  37 19   8.1   4.5
 38000 -48.3 -54.9  330  36 19   8.3   4.5 | -48.4 -55.1  335  36 19   8.1   4.5
 36000 -43.3 -45.9  330  34 17   8.3   4.5 | -43.5 -46.3  335  35 18   8.2   4.5
 34000 -38.4 -37.1  330  34 17   8.2   4.5 | -38.6 -37.5  335  34 17   8.2   4.5
 32000 -33.5 -28.3  335  34 18   8.2   4.5 | -33.7 -28.7  335  33 17   8.4   4.6
 30000 -28.9 -20.0  335  37 19   7.6   4.2 | -29.1 -20.4  335  35 18   7.5   4.1
 29000 -26.1 -15.0  340  39 20   7.6   4.2 | -26.3 -15.3  340  36 18   7.5   4.1
 28000 -23.8 -10.8  340  41 21   7.0   3.8 | -24.1 -11.4  340  36 19   7.5   4.1
 27000 -21.7  -7.1  340  41 21   7.1   3.9 | -21.8  -7.2  340  36 19   7.5   4.1
 26000 -19.6  -3.3  340  42 21   7.1   3.9 | -19.6  -3.3  345  36 18   7.5   4.1
 25000 -17.5   0.5  345  42 22   6.8   3.8 | -17.4   0.7  345  35 18   7.0   3.8
 24000 -15.5   4.1  340  40 21   6.7   3.7 | -15.4   4.3  340  34 17   6.7   3.7
 23000 -13.6   7.5  340  38 20   6.7   3.7 | -13.4   7.9  340  32 17   6.7   3.7
 22000 -11.6  11.1  335  37 19   6.0   3.3 | -11.4  11.5  335  31 16   5.9   3.2
 21000  -9.9  14.2  330  34 17   5.6   3.1 |  -9.8  14.4  330  30 15   5.5   3.0
 20000  -8.3  17.1  325  31 16   5.6   3.1 |  -8.1  17.4  325  29 15   5.5   3.0
 19500  -7.5  18.5  320  30 15   5.6   3.1 |  -7.3  18.9  325  29 15   5.6   3.0
 19000  -6.7  19.9  315  29 15   5.5   3.0 |  -6.5  20.3  320  28 15   6.0   3.3
 18500  -5.9  21.4  310  28 14   5.6   3.1 |  -5.6  21.9  320  28 15   6.0   3.3
 18000  -5.1  22.8  305  27 14   6.0   3.3 |  -4.7  23.5  315  28 14   6.2   3.4
 17500  -4.2  24.4  300  26 13   6.3   3.5 |  -3.8  25.2  310  28 14   6.5   3.5
 17000  -3.3  26.1  300  25 13   6.5   3.6 |  -2.9  26.8  310  28 15   6.6   3.6
 16500  -2.4  27.7  300  23 12   7.4   4.1 |  -2.0  28.4  305  28 14   6.8   3.7
 16000  -1.4  29.5  300  21 11   7.5   4.1 |  -1.1  30.0  305  26 14   6.9   3.8
 15500   0.1  32.2  300  17  9   7.3   4.0 |   0.3  32.5  305  24 12   6.7   3.7
 15000   1.1  34.0  305  15  8   7.3   4.0 |   1.2  34.2  305  22 11   6.9   3.8
 14500   2.2  36.0  310  13  7   7.9   4.4 |   2.1  35.8  310  20 10   6.2   3.4
 14000   3.3  37.9  315  12  6   7.9   4.3 |   2.9  37.2  315  18  9   6.4   3.5
 13500   4.4  39.9  320  11  6   7.7   4.2 |   3.8  38.8  315  17  9   5.6   3.1
 13000   5.6  42.1  320  11  6   7.7   4.2 |   4.5  40.1  325  15  8   5.6   3.1
 12500   6.6  43.9  325  11  5   6.0   3.3 |   5.3  41.5  330  14  7   5.7   3.1
 12000   7.3  45.1  325  10  5   5.4   3.0 |   6.1  43.0  335  13  7   5.8   3.2
 11500   8.0  46.4  325   9  5   3.6   2.0 |   6.9  44.4  345  12  6   6.5   3.6
 11000   8.3  46.9  330   8  4   2.6   1.4 |   7.9  46.2  345  11  5   6.8   3.7
 10500   8.5  47.3  335   7  4   2.3   1.3 |   8.8  47.8  350  10  5   5.0   2.7
 10250   8.7  47.7  335   7  3   3.2   1.7 |   9.1  48.4  355   9  5   5.4   2.9
 10000   8.9  48.0  340   6  3   5.1   2.8 |   9.6  49.3  360   9  4   7.8   4.3
  9750   9.3  48.7  355   5  3   5.6   3.1 |  10.1  50.2  005   8  4   7.6   4.2
  9500   9.7  49.5  005   5  2   5.1   2.8 |  10.6  51.1  015   7  4   6.5   3.6
  9250  10.0  50.0  010   5  3   4.6   2.5 |  11.0  51.8  020   7  4   5.8   3.2
  9000  10.3  50.5  010   5  3   5.6   3.1 |  11.5  52.7  025   7  4   7.3   4.0
  8750  10.8  51.4  010   6  3   6.2   3.4 |  12.0  53.6  030   8  4   8.0   4.4
  8500  11.1  52.0  010   7  4   5.1   2.8 |  12.5  54.5  035   7  4   7.2   4.0
  8250  11.5  52.7  010   8  4   4.7   2.6 |  13.0  55.4  040   7  3   6.8   3.7
  8000  11.8  53.2  010   9  5   5.0   2.8 |  13.4  56.1  045   6  3   8.4   4.6
  7750  12.1  53.8  010  10  5   5.0   2.7 |  14.0  57.2  050   6  3  10.1   5.6
  7500  12.5  54.5  010  10  5   4.5   2.5 |  14.7  58.5  050   5  3   9.9   5.4
  7250  12.8  55.0  010   9  5   4.5   2.5 |  15.4  59.7  050   5  3   9.6   5.3
  7000  13.1  55.6  010   9  4   4.3   2.4 |  16.2  61.2  050   5  3  10.6   5.8
  6750  13.4  56.1  015   8  4   6.9   3.8 |  17.0  62.6  050   5  3  10.9   6.0
  6500  14.0  57.2  010   7  4   9.2   5.0 |  17.7  63.9  050   5  3  10.1   5.6
  6250  14.6  58.3  360   6  3   8.4   4.6 |  18.5  65.3  050   5  3  10.4   5.7
  6000  15.2  59.4  350   5  3   9.4   5.1 |  19.2  66.6  050   5  3  10.2   5.6
  5750  16.0  60.8  345   5  3  13.5   7.4 |  20.2  68.4  050   5  2  16.9   9.3
  5500  17.2  63.0  350   5  2  17.7   9.7 |  21.8  71.2  050   5  2  28.1  15.4

           06/26/2015 at 1500 MDT          |       06/26/2015 at 1800 MDT
                                           |
K index... +27.0  LI... -3.7               | K index... +31.0  LI... -2.3
CAPE... +1221.8  CIN... -3.0               | CAPE... +733.6  CIN... -5.8
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.1 -85.2  300  19 10   0.2   0.1 | -65.2 -85.4  290  16  8   0.3   0.2
 45000 -62.1 -79.8  315  28 14   5.2   2.9 | -62.0 -79.6  300  21 11   5.3   2.9
 40000 -53.5 -64.3  325  35 18   8.4   4.6 | -53.3 -63.9  320  31 16   8.1   4.4
 38000 -48.5 -55.3  330  34 18   8.4   4.6 | -48.5 -55.3  325  31 16   8.1   4.4
 36000 -43.4 -46.1  335  34 17   8.2   4.5 | -43.7 -46.7  330  31 16   8.1   4.4
 34000 -38.7 -37.7  335  33 17   8.0   4.4 | -38.8 -37.8  325  31 16   8.1   4.4
 32000 -33.9 -29.0  335  32 17   8.1   4.5 | -33.9 -29.0  325  32 16   8.6   4.7
 30000 -28.8 -19.8  335  33 17   7.5   4.1 | -28.8 -19.8  335  32 17   7.6   4.2
 29000 -26.6 -15.9  335  34 18   7.5   4.1 | -26.5 -15.7  335  33 17   7.6   4.2
 28000 -24.3 -11.7  340  34 18   7.6   4.2 | -24.2 -11.6  340  33 17   7.8   4.3
 27000 -22.0  -7.6  340  34 17   7.6   4.2 | -21.9  -7.4  340  33 17   7.8   4.3
 26000 -19.8  -3.6  340  33 17   7.6   4.2 | -19.5  -3.1  340  33 17   7.8   4.3
 25000 -17.5   0.5  340  32 16   7.3   4.0 | -17.2   1.0  340  33 17   7.3   4.0
 24000 -15.4   4.3  335  31 16   7.1   3.9 | -15.1   4.8  340  32 16   7.1   3.9
 23000 -13.3   8.1  335  31 16   7.1   3.9 | -13.0   8.6  335  31 16   7.2   3.9
 22000 -11.2  11.8  330  30 15   6.4   3.5 | -10.9  12.4  335  30 15   6.5   3.6
 21000  -9.4  15.1  330  30 15   6.1   3.3 |  -9.0  15.8  330  31 16   6.3   3.5
 20000  -7.6  18.3  325  30 15   6.1   3.4 |  -7.2  19.0  330  32 16   6.3   3.5
 19500  -6.7  19.9  325  30 15   6.1   3.4 |  -6.3  20.7  330  32 17   6.3   3.4
 19000  -5.8  21.6  325  30 15   6.2   3.4 |  -5.4  22.3  330  32 17   6.0   3.3
 18500  -4.9  23.2  320  30 15   6.3   3.5 |  -4.5  23.9  330  32 17   6.0   3.3
 18000  -4.1  24.6  320  30 15   6.6   3.6 |  -3.7  25.3  325  32 17   5.9   3.2
 17500  -3.1  26.4  315  29 15   6.7   3.7 |  -2.9  26.8  325  32 16   6.0   3.3
 17000  -2.2  28.0  315  29 15   6.7   3.7 |  -2.1  28.2  325  31 16   6.2   3.4
 16500  -1.3  29.7  310  29 15   6.3   3.5 |  -1.3  29.7  320  30 15   6.6   3.6
 16000   0.1  32.2  305  28 14   6.5   3.6 |   0.0  32.0  315  28 14   6.7   3.7
 15500   1.0  33.8  305  27 14   6.8   3.7 |   1.0  33.8  315  26 13   6.6   3.6
 15000   2.0  35.6  305  26 13   6.9   3.8 |   1.9  35.4  315  24 12   6.6   3.6
 14500   2.8  37.0  305  24 12   5.7   3.1 |   2.8  37.0  320  22 11   5.9   3.2
 14000   3.6  38.5  305  22 11   5.9   3.2 |   3.6  38.5  325  21 11   6.2   3.4
 13500   4.4  39.9  310  19 10   5.6   3.1 |   4.3  39.7  330  19 10   4.0   2.2
 13000   5.2  41.4  315  17  9   5.6   3.1 |   4.9  40.8  335  16  8   3.8   2.1
 12500   6.0  42.8  325  14  7   6.0   3.3 |   5.5  41.9  345  13  7   6.1   3.4
 12000   6.8  44.2  330  11  6   6.1   3.3 |   6.4  43.5  355   9  4   6.6   3.6
 11500   7.6  45.7  340   8  4   6.6   3.6 |   7.4  45.3  020   6  3   7.7   4.2
 11000   8.5  47.3  005   6  3   6.9   3.8 |   8.5  47.3  035   5  3   8.2   4.5
 10500   9.3  48.7  035   5  3   3.5   1.9 |   9.5  49.1  045   5  3   3.1   1.7
 10250   9.5  49.1  040   5  3   6.7   3.7 |   9.7  49.5  045   5  3   7.4   4.1
 10000  10.3  50.5  045   6  3  12.7   7.0 |  10.7  51.3  045   5  3  15.2   8.4
  9750  11.1  52.0  050   6  3  11.2   6.1 |  11.7  53.1  045   5  3  12.8   7.0
  9500  11.8  53.2  055   6  3   8.4   4.6 |  12.5  54.5  045   5  3   9.1   5.0
  9250  12.3  54.1  055   6  3   6.9   3.8 |  13.1  55.6  045   5  3   7.3   4.0
  9000  12.9  55.2  055   6  3  10.9   6.0 |  13.7  56.7  045   5  3  11.2   6.2
  8750  13.8  56.8  055   6  3  12.1   6.6 |  14.6  58.3  045   5  3  12.0   6.6
  8500  14.6  58.3  055   6  3   9.9   5.5 |  15.4  59.7  045   5  3   9.6   5.3
  8250  15.3  59.5  055   6  3   9.1   5.0 |  16.1  61.0  045   5  3   8.7   4.8
  8000  16.0  60.8  055   6  3  11.1   6.1 |  16.8  62.2  045   5  3  10.7   5.9
  7750  16.9  62.4  055   6  3  11.6   6.4 |  17.6  63.7  045   5  3  11.2   6.1
  7500  17.7  63.9  050   6  3   9.6   5.3 |  18.4  65.1  045   5  3   9.4   5.2
  7250  18.4  65.1  050   6  3   9.8   5.4 |  19.1  66.4  045   5  3   9.3   5.1
  7000  19.1  66.4  050   6  3   9.8   5.4 |  19.8  67.6  040   5  3  10.4   5.7
  6750  19.9  67.8  050   6  3  10.1   5.6 |  20.6  69.1  045   5  3  10.6   5.8
  6500  20.6  69.1  050   6  3  10.5   5.7 |  21.3  70.3  045   5  3   9.6   5.3
  6250  21.4  70.5  050   6  3  10.2   5.6 |  22.1  71.8  040   5  2   9.8   5.4
  6000  22.2  72.0  050   6  3  11.0   6.0 |  22.8  73.0  040   5  2  10.1   5.5
  5750  23.1  73.6  050   6  3  17.6   9.7 |  23.6  74.5  040   5  2  12.9   7.1
  5500  24.8  76.6  050   6  3  26.1  14.3 |  24.7  76.5  045   5  2  16.2   8.9
________________________________________________________________________________

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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