Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 221238
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0638 MDT Monday, May 22, 2017

This forecast is for Monday, May 22, 2017:

If the trigger temperature of 54.9 F/12.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 714 ft/min (3.6 m/s)
   Maximum height of thermals.................. 14503 ft MSL (9218 ft AGL)

Forecast maximum temperature................... 67.0 F/19.9 C
Time of trigger temperature.................... 1000 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13589 ft MSL (8304 ft AGL)
Thermal soaring outlook for Tuesday 05/23...... Fair

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... Becoming poor by 1500
Height of stable layer (12-18K ft MSL)......... 14128 ft MSL (8843 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 15111 ft MSL (9826 ft AGL)
Wave soaring outlook for Tuesday 05/23......... Poor

Remarks... Cold front with gusty north winds and numerous showers late this
           afternoon and evening

Sunrise/Sunset.................... 05:38:42 / 20:13:41 MDT
Total possible sunshine........... 14 hr 35 min 0 sec (875 min 0 sec)
Altitude of sun at 12:56:11 MDT... 70.74 degrees

Upper air data from rawinsonde observation taken on 05/22/2017 at 0600 MDT

Freezing level.................. 9577 ft MSL (4292 ft AGL)
Convective condensation level... 10547 ft MSL (5262 ft AGL)
Lifted condensation level....... 13013 ft MSL (7727 ft AGL)
Lifted index.................... -1.5
K index......................... +14.6

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  -56.0 -68.8   295   30   15   1.1   0.6  106.2 223.1    49.7      M    M
 45000  -54.1 -65.4   280   33   17  -0.3  -0.2   84.5 184.2    39.9      M    M
 40000  -55.4 -67.7   290   35   18  -0.8  -0.4   58.4 137.0    25.6      M    M
 38000  -56.0 -68.8   290   23   12  -2.3  -1.3   48.8 119.8    19.8      M    M
 36000  -57.3 -71.1   320   29   15  -3.5  -1.9   38.2 100.7    13.0      M    M
 34000  -53.9 -65.0   290   23   12   6.4   3.5   34.8  94.6    10.9      M    M
 32000  -50.0 -58.0   280   26   14   6.4   3.5   31.9  89.5     9.1      M    M
 30000  -45.7 -50.3   275   30   15  10.6   5.8   30.0  86.1     8.0      M    M
 29000  -42.7 -44.9   270   29   15  10.1   5.6   30.2  86.3     8.2      M    M
 28000  -39.2 -38.6   265   29   15   8.7   4.8   30.0  86.1     8.2      M    M
 27000  -36.6 -33.9   270   29   15   8.7   4.8   29.5  85.1     7.9      M    M
 26000  -34.0 -29.2   270   28   15   8.7   4.8   29.1  84.4     7.6      M    M
 25000  -31.4 -24.5   275   28   14   8.7   4.8   28.8  83.9     7.5      M    M
 24000  -28.8 -19.8   280   29   15   8.4   4.6   28.3  83.0     7.2      M    M
 23000  -26.3 -15.3   285   28   14   8.4   4.6   27.7  81.9     6.7      M    M
 22000  -23.8 -10.8   285   27   14   8.4   4.6   27.2  81.0     6.4      M    M
 21000  -21.3  -6.3   290   26   13   8.6   4.7   26.9  80.4     6.1      M    M
 20000  -19.1  -2.4   295   25   13   6.9   3.8   26.1  78.9     5.5      M    M
 19500  -18.0  -0.4   295   25   13   7.6   4.2   25.6  78.1     5.2      M    M
 19000  -16.8   1.8   295   24   12   8.8   4.8   25.4  77.6     5.0      M    M
 18500  -15.7   3.7   295   23   12   7.3   4.0   25.0  77.0     4.7      M    M
 18000  -15.0   5.0   295   22   11   2.8   1.6   24.2  75.5     3.9      M    M
 17500  -13.8   7.2   300   22   11   8.0   4.4   23.8  74.8     3.6      M    M
 17000  -13.1   8.4   300   22   11   5.4   3.0   23.0  73.4     2.9      M    M
 16500  -12.3   9.9   305   23   12   6.8   3.7   22.3  72.2     2.3      M    M
 16000  -11.2  11.8   310   23   12   7.4   4.1   21.9  71.4     2.0      M    M
 15500  -10.1  13.8   315   24   12   5.5   3.0   21.4  70.6     1.6      M    M
 15000   -9.4  15.1   325   26   13   4.9   2.7   20.6  69.1     0.8      M    M
 14500   -8.5  16.7   325   25   13   4.9   2.7   20.0  68.0     0.3      M    M
 14000   -8.6  16.5   325   24   12  -0.2  -0.1   17.6  63.7    -2.1    701  3.6
 13500   -8.7  16.3   325   23   12   2.7   1.5   16.0  60.8    -3.6    688  3.5
 13000   -7.6  18.3   320   22   11   8.5   4.7   15.6  60.1    -4.0    641  3.3
 12500   -6.4  20.5   320   21   11   8.4   4.6   15.4  59.7    -4.2    589  3.0
 12000   -5.1  22.8   320   20   10   8.6   4.7   15.2  59.3    -4.4    536  2.7
 11500   -4.0  24.8   335   17    9   6.5   3.6   14.8  58.7    -4.8    489  2.5
 11000   -3.1  26.4   345   16    8   6.7   3.7   14.3  57.8    -5.4    445  2.3
 10500   -2.1  28.2   350   12    6   6.2   3.4   13.9  56.9    -5.9    402  2.0
 10250   -1.7  28.9   350   11    6   6.8   3.7   13.6  56.4    -6.2    383  1.9
 10000   -1.1  30.0   350   11    5   9.3   5.1   13.4  56.2    -6.4    357  1.8
  9750   -0.4  31.3   355   10    5   9.7   5.3   13.4  56.2    -6.4    328  1.7
  9500    0.3  32.5   355   10    5   9.6   5.3   13.4  56.2    -6.4    299  1.5
  9250    1.1  34.0   360    9    5   9.6   5.3   13.4  56.2    -6.5    270  1.4
  9000    1.8  35.2   360    9    5   9.7   5.3   13.4  56.2    -6.5    241  1.2
  8750    2.5  36.5   360    9    5   9.5   5.2   13.4  56.1    -6.5    212  1.1
  8500    3.2  37.8   005   10    5   8.2   4.5   13.4  56.1    -6.6    185  0.9
  8250    3.7  38.7   005   10    5   7.4   4.1   13.2  55.8    -6.8    161  0.8
  8000    4.3  39.7   005   10    5   7.7   4.2   13.0  55.5    -7.0    138  0.7
  7750    4.8  40.6   005    9    5   7.6   4.2   12.9  55.2    -7.2    114  0.6
  7500    5.3  41.5   005    8    4   7.6   4.2   12.7  54.9    -7.4     90  0.5
  7250    5.9  42.6   360    8    4   7.6   4.2   12.6  54.6    -7.6     66  0.3
  7000    6.4  43.5   360    7    4   7.7   4.2   12.4  54.3    -7.8     43  0.2
  6750    7.0  44.6   350    6    3   7.6   4.1   12.2  54.0    -8.0     19  0.1
  6500    7.4  45.3   340    6    3   3.5   1.9   12.0  53.6    -8.3      M    M
  6250    7.4  45.3   330    6    3   0.6   0.3   11.3  52.4    -9.0      M    M
  6000    7.5  45.5   320    6    3   1.4   0.8   10.7  51.2    -9.7      M    M
  5750    7.5  45.5   310    4    2   1.2   0.7   10.1  50.1   -10.4      M    M
  5500    7.6  45.7   280    2    1   1.5   0.8    9.4  49.0   -11.1      M    M

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

           05/22/2017 at 0900 MDT          |       05/22/2017 at 1200 MDT
                                           |
CAPE...    +1.1    LI...       +2.7        | CAPE...    +7.8    LI...       +2.6
CINH...    -3.6    K Index...  +1.2        | CINH...    -5.7    K Index... +10.1
                                           |
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 -55.8 -68.4  295  12  6   0.6   0.3 | -55.5 -67.9  300  12  6   0.5   0.3
 45000 -55.0 -67.0  295  16  8  -0.9  -0.5 | -54.8 -66.6  305  16  8  -1.5  -0.8
 40000 -56.6 -69.9  315  18  9  -1.1  -0.6 | -57.5 -71.5  320  21 11  -1.8  -1.0
 38000 -56.4 -69.5  325  19 10   1.7   0.9 | -57.1 -70.8  325  23 12   2.7   1.5
 36000 -55.2 -67.4  335  20 10   1.7   0.9 | -55.3 -67.5  330  24 13   2.7   1.5
 34000 -53.2 -63.8  340  20 11   7.0   3.9 | -52.8 -63.0  335  25 13   7.4   4.1
 32000 -48.9 -56.0  335  19 10   7.1   3.9 | -48.3 -54.9  330  24 12   7.5   4.1
 30000 -44.4 -47.9  335  17  9   8.5   4.6 | -43.7 -46.7  330  22 11   8.1   4.5
 29000 -41.9 -43.4  330  16  8   8.5   4.6 | -41.3 -42.3  325  21 11   8.1   4.5
 28000 -39.3 -38.7  325  15  8   8.5   4.6 | -38.8 -37.8  325  20 10   8.1   4.5
 27000 -36.8 -34.2  325  14  7   8.4   4.6 | -36.4 -33.5  320  19 10   8.0   4.4
 26000 -34.3 -29.7  320  14  7   8.4   4.6 | -34.0 -29.2  315  19 10   8.0   4.4
 25000 -31.8 -25.2  320  15  7   8.4   4.6 | -31.6 -24.9  315  19 10   8.0   4.4
 24000 -29.3 -20.7  320  15  8   8.1   4.4 | -29.3 -20.7  315  19 10   7.9   4.4
 23000 -26.9 -16.4  320  15  7   7.9   4.3 | -26.9 -16.4  315  19 10   7.9   4.3
 22000 -24.5 -12.1  320  14  7   7.9   4.3 | -24.5 -12.1  315  19 10   7.9   4.3
 21000 -22.2  -8.0  325  14  7   7.1   3.9 | -22.2  -8.0  315  18  9   7.3   4.0
 20000 -19.6  -3.3  325  14  7   7.2   3.9 | -20.0  -4.0  315  17  9   7.3   4.0
 19500 -18.5  -1.3  325  14  7   7.2   3.9 | -18.4  -1.1  315  16  8   7.3   4.0
 19000 -17.4   0.7  325  14  7   7.1   3.9 | -17.3   0.9  315  16  8   7.2   3.9
 18500 -16.4   2.5  325  13  7   6.6   3.6 | -16.3   2.7  320  16  8   6.2   3.4
 18000 -15.4   4.3  325  13  7   6.7   3.7 | -15.4   4.3  320  16  8   6.2   3.4
 17500 -14.4   6.1  330  13  7   6.5   3.6 | -14.4   6.1  320  15  8   6.0   3.3
 17000 -13.5   7.7  330  13  7   6.5   3.6 | -13.6   7.5  320  15  8   5.9   3.3
 16500 -12.5   9.5  330  13  7   6.5   3.5 | -12.7   9.1  320  14  7   6.0   3.3
 16000 -11.5  11.3  330  13  7   6.4   3.5 | -11.8  10.8  320  14  7   6.0   3.3
 15500 -10.6  12.9  335  13  7   6.4   3.5 | -10.9  12.4  320  13  7   6.1   3.3
 15000  -9.6  14.7  335  13  7   6.3   3.5 | -10.0  14.0  325  13  7   6.6   3.6
 14500  -8.7  16.3  335  13  7   6.3   3.4 |  -9.0  15.8  325  12  6   6.5   3.6
 14000  -7.8  18.0  340  13  6   6.6   3.6 |  -8.0  17.6  325  12  6   6.7   3.7
 13500  -6.8  19.8  340  12  6   6.6   3.6 |  -7.0  19.4  325  11  6   6.6   3.6
 13000  -5.8  21.6  340  12  6   6.7   3.7 |  -6.0  21.2  325  10  5   7.5   4.1
 12500  -4.8  23.4  340  12  6   6.7   3.7 |  -4.9  23.2  325   9  5   7.5   4.1
 12000  -3.8  25.2  345  12  6   6.9   3.8 |  -3.8  25.2  330   9  4   8.2   4.5
 11500  -2.8  27.0  345  11  6   6.9   3.8 |  -2.5  27.5  330   8  4   8.3   4.5
 11000  -1.7  28.9  345  11  6   7.2   4.0 |  -1.3  29.7  330   8  4   8.8   4.8
 10500  -0.6  30.9  340  11  6   7.0   3.8 |   0.0  32.0  330   7  4   8.7   4.8
 10250  -0.1  31.8  340  11  5   8.5   4.7 |   0.7  33.3  330   7  4   9.3   5.1
 10000   0.6  33.1  340  10  5   8.3   4.6 |   1.4  34.5  330   7  3   9.3   5.1
  9750   1.1  34.0  340  10  5   6.7   3.7 |   2.0  35.6  330   6  3   8.7   4.8
  9500   1.6  34.9  340  10  5   7.1   3.9 |   2.7  36.9  330   6  3   9.0   5.0
  9250   2.1  35.8  340   9  5   7.2   3.9 |   3.3  37.9  330   6  3   8.3   4.5
  9000   2.6  36.7  340   9  4   7.6   4.2 |   3.9  39.0  325   5  3   8.5   4.7
  8750   3.2  37.8  335   8  4   8.0   4.4 |   4.6  40.3  325   5  2   9.7   5.3
  8500   3.8  38.8  330   7  4   8.1   4.5 |   5.3  41.5  325   4  2   9.7   5.3
  8250   4.3  39.7  330   7  3   7.9   4.4 |   6.0  42.8  320   4  2   9.5   5.2
  8000   4.9  40.8  325   6  3   7.8   4.3 |   6.7  44.1  320   4  2   9.5   5.2
  7750   5.4  41.7  320   5  3   6.3   3.4 |   7.4  45.3  320   3  2   9.9   5.4
  7500   5.8  42.4  315   5  2   6.2   3.4 |   8.2  46.8  320   3  2  10.0   5.5
  7250   6.3  43.3  305   4  2   7.4   4.1 |   8.9  48.0  320   3  2   9.9   5.5
  7000   6.8  44.2  295   4  2   7.4   4.1 |   9.6  49.3  320   3  1   9.9   5.5
  6750   7.3  45.1  285   3  2   7.1   3.9 |  10.4  50.7  320   3  1  10.0   5.5
  6500   7.8  46.0  280   3  2   6.3   3.5 |  11.1  52.0  320   3  1  10.1   5.5
  6250   8.2  46.8  275   3  2   6.3   3.5 |  11.9  53.4  320   3  1  10.6   5.8
  6000   8.6  47.5  265   3  1   5.4   3.0 |  12.7  54.9  320   2  1   9.2   5.1
  5750   9.0  48.2  255   3  1   9.3   5.1 |  13.4  56.1  325   2  1  14.3   7.9
  5500  10.0  50.0  255   3  1  17.7   9.7 |  14.9  58.8  320   2  1  27.7  15.2

           05/22/2017 at 1500 MDT          |       05/22/2017 at 1800 MDT
                                           |
CAPE...  +148.4    LI...       -0.6        | CAPE...   +97.6    LI...       -0.7
CINH...    -2.8    K Index... +21.6        | CINH...    -7.7    K Index... +27.4
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -55.9 -68.6  305  13  6   0.3   0.1 | -55.5 -67.9  320  13  7   0.5   0.3
 45000 -55.5 -67.9  310  16  8  -0.4  -0.2 | -54.8 -66.6  320  17  9   0.3   0.2
 40000 -56.2 -69.2  315  26 13  -0.4  -0.2 | -54.3 -65.7  320  25 13   0.3   0.2
 38000 -55.9 -68.6  315  28 14   1.3   0.7 | -54.2 -65.6  320  26 14  -0.1  -0.0
 36000 -55.0 -67.0  315  29 15   1.3   0.7 | -54.3 -65.7  315  27 14  -0.1  -0.0
 34000 -53.1 -63.6  315  29 15   7.2   4.0 | -53.4 -64.1  310  28 14   5.5   3.0
 32000 -48.7 -55.7  315  28 14   7.3   4.0 | -50.0 -58.0  310  27 14   5.7   3.1
 30000 -44.1 -47.4  315  27 14   8.4   4.6 | -46.0 -50.8  310  26 13   8.8   4.8
 29000 -41.6 -42.9  315  26 13   8.4   4.6 | -43.4 -46.1  310  26 13   8.8   4.9
 28000 -39.1 -38.4  310  25 13   8.4   4.6 | -40.7 -41.3  310  25 13   8.8   4.9
 27000 -36.6 -33.9  310  24 12   7.9   4.3 | -38.1 -36.6  310  24 12   8.9   4.9
 26000 -34.3 -29.7  310  23 12   7.9   4.3 | -35.4 -31.7  310  24 12   8.9   4.9
 25000 -31.9 -25.4  305  22 12   7.9   4.3 | -32.8 -27.0  310  24 12   8.9   4.9
 24000 -29.6 -21.3  305  22 11   7.6   4.2 | -30.1 -22.2  310  23 12   8.5   4.7
 23000 -27.3 -17.1  305  21 11   7.5   4.1 | -27.7 -17.9  310  23 12   8.3   4.5
 22000 -25.1 -13.2  310  20 10   7.5   4.1 | -25.2 -13.4  310  22 11   8.3   4.5
 21000 -22.9  -9.2  310  19 10   6.9   3.8 | -22.8  -9.0  310  21 11   7.7   4.2
 20000 -20.8  -5.4  310  18  9   6.9   3.8 | -20.5  -4.9  310  20 10   7.7   4.2
 19500 -19.8  -3.6  310  17  9   6.9   3.8 | -18.8  -1.8  310  19 10   7.7   4.2
 19000 -18.3  -0.9  310  16  8   6.9   3.8 | -17.7   0.1  310  19 10   7.7   4.2
 18500 -17.2   1.0  315  16  8   6.8   3.8 | -16.6   2.1  305  19 10   7.1   3.9
 18000 -16.2   2.8  315  15  8   6.8   3.8 | -15.5   4.1  305  18  9   7.2   3.9
 17500 -15.2   4.6  315  15  8   7.0   3.8 | -14.5   5.9  305  18  9   7.2   3.9
 17000 -14.2   6.4  315  14  7   7.0   3.8 | -13.4   7.9  305  17  9   7.2   3.9
 16500 -13.1   8.4  315  14  7   6.9   3.8 | -12.4   9.7  305  17  9   7.1   3.9
 16000 -12.1  10.2  315  13  7   6.9   3.8 | -11.3  11.7  305  16  8   7.0   3.9
 15500 -11.1  12.0  315  12  6   7.0   3.8 | -10.3  13.5  300  16  8   7.1   3.9
 15000 -10.0  14.0  310  12  6   7.9   4.3 |  -9.3  15.3  300  16  8   7.2   3.9
 14500  -8.9  16.0  310  11  6   7.8   4.3 |  -8.2  17.2  300  15  8   7.1   3.9
 14000  -7.7  18.1  310  10  5   8.7   4.8 |  -7.2  19.0  300  15  8   7.4   4.0
 13500  -6.4  20.5  310  10  5   8.6   4.7 |  -6.1  21.0  300  14  7   7.4   4.0
 13000  -5.1  22.8  310   9  5   8.9   4.9 |  -5.0  23.0  300  13  7   7.3   4.0
 12500  -3.8  25.2  310   9  5   8.9   4.9 |  -4.0  24.8  300  12  6   7.3   4.0
 12000  -2.5  27.5  305   9  4   9.3   5.1 |  -2.9  26.8  305  11  6   7.1   3.9
 11500  -1.1  30.0  305   8  4   9.3   5.1 |  -1.9  28.6  310  11  5   7.1   3.9
 11000   0.3  32.5  305   8  4   9.3   5.1 |  -0.9  30.4  315  10  5   6.5   3.6
 10500   1.7  35.1  300   7  4   9.4   5.1 |   0.0  32.0  325  10  5   6.5   3.6
 10250   2.4  36.3  300   7  4   8.9   4.9 |   0.5  32.9  330  10  5   5.7   3.1
 10000   3.0  37.4  300   7  3   9.2   5.1 |   0.8  33.4  335  10  5   5.3   2.9
  9750   3.7  38.7  300   7  3   9.8   5.4 |   1.3  34.3  335  10  5   5.7   3.1
  9500   4.4  39.9  300   7  3  10.0   5.5 |   1.7  35.1  340  10  5   6.0   3.3
  9250   5.2  41.4  300   6  3   8.8   4.8 |   2.1  35.8  345  11  5   4.5   2.5
  9000   5.8  42.4  305   6  3   9.0   4.9 |   2.4  36.3  350  11  6   4.0   2.2
  8750   6.5  43.7  305   6  3  10.6   5.8 |   2.7  36.9  350  12  6   6.1   3.4
  8500   7.3  45.1  305   6  3  10.4   5.7 |   3.2  37.8  355  12  6   6.5   3.6
  8250   8.1  46.6  305   6  3  10.3   5.6 |   3.7  38.7  355  13  7   5.8   3.2
  8000   8.8  47.8  305   6  3  10.0   5.5 |   4.1  39.4  360  14  7   5.5   3.0
  7750   9.6  49.3  305   6  3   9.6   5.3 |   4.5  40.1  360  14  7   6.3   3.4
  7500  10.3  50.5  305   6  3   9.6   5.3 |   5.0  41.0  360  14  7   7.2   3.9
  7250  11.0  51.8  305   6  3   9.9   5.4 |   5.5  41.9  360  14  7   7.8   4.3
  7000  11.8  53.2  305   5  3   9.9   5.4 |   6.1  43.0  005  14  7   7.8   4.3
  6750  12.5  54.5  305   5  3  10.0   5.5 |   6.7  44.1  005  14  7   8.9   4.9
  6500  13.3  55.9  305   5  3  10.0   5.5 |   7.4  45.3  005  14  7   9.8   5.4
  6250  14.0  57.2  305   5  3  10.1   5.6 |   8.1  46.6  005  13  7   9.6   5.3
  6000  14.7  58.5  305   5  2   9.2   5.1 |   8.8  47.8  005  12  6   9.0   4.9
  5750  15.5  59.9  305   5  2  12.8   7.0 |   9.5  49.1  005  12  6  11.8   6.5
  5500  16.8  62.2  305   4  2  22.5  12.4 |  10.6  51.1  005  10  5  18.0   9.9
________________________________________________________________________________

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.

CINH (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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