Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 201233
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0533 MST Monday, February 20, 2017

This forecast is for Monday, February 20, 2017:

If the trigger temperature of 49.4 F/9.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1220 ft/min (6.2 m/s)
   Maximum height of thermals.................. 19103 ft MSL (13769 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... 0945 MST
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................. 14284 ft MSL (8951 ft AGL)
Thermal soaring outlook for Tuesday 02/21...... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 15200 ft MSL (9866 ft AGL)
Wave soaring outlook for Tuesday 02/21......... Fair

Remarks...

Sunrise/Sunset.................... 06:44:40 / 17:41:37 MST
Total possible sunshine........... 10 hr 56 min 57 sec (656 min 57 sec)
Altitude of sun at 12:13:09 MST... 39.50 degrees

Upper air data from numerical model forecast valid on 02/20/2017 at 0500 MST

Freezing level.................. 8216 ft MSL (2882 ft AGL)
Convective condensation level... 15646 ft MSL (10312 ft AGL)
Lifted condensation level....... 16761 ft MSL (11427 ft AGL)
Lifted index.................... -0.2
K index......................... -10.2

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  -59.0 -74.2   275   17    9   3.8   2.1      M     M       M      M    M
 45000  -53.2 -63.8   290   22   11   4.9   2.7      M     M       M      M    M
 40000  -45.9 -50.6   305   25   13   4.8   2.6      M     M       M      M    M
 38000  -43.3 -45.9   310   27   14   3.1   1.7      M     M       M      M    M
 36000  -41.5 -42.7   310   28   15   3.1   1.7      M     M       M      M    M
 34000  -39.8 -39.6   310   30   15   0.8   0.4      M     M       M      M    M
 32000  -39.1 -38.4   310   29   15   1.1   0.6      M     M       M      M    M
 30000  -38.5 -37.3   305   29   15   1.2   0.7   40.4 104.8    16.9      M    M
 29000  -38.1 -36.6   305   27   14   1.2   0.7   36.8  98.3    14.4      M    M
 28000  -37.8 -36.0   300   25   13   1.2   0.7   33.4  92.1    12.0      M    M
 27000  -37.4 -35.3   300   24   12   1.1   0.6   30.2  86.4     9.7      M    M
 26000  -36.6 -33.9   300   22   11   3.6   2.0   27.5  81.4     7.6      M    M
 25000  -35.5 -31.9   295   20   10   3.7   2.0   25.1  77.2     5.8      M    M
 24000  -34.4 -29.9   295   18    9   3.8   2.1   22.9  73.2     4.1      M    M
 23000  -32.8 -27.0   300   17    9   7.1   3.9   21.3  70.3     2.9      M    M
 22000  -30.6 -23.1   300   16    8   7.2   3.9   20.3  68.6     2.1      M    M
 21000  -28.5 -19.3   305   16    8   7.1   3.9   19.5  67.0     1.4      M    M
 20000  -25.7 -14.3   310   17    9   7.6   4.2   18.4  65.1     0.5      M    M
 19500  -24.5 -12.1   315   17    9   7.6   4.2   18.0  64.4     0.2      M    M
 19000  -23.4 -10.1   315   17    9   7.6   4.2   17.7  63.8    -0.1   1200  6.1
 18500  -22.2  -8.0   320   18    9   7.6   4.1   17.3  63.2    -0.4   1151  5.8
 18000  -21.1  -6.0   320   18    9   7.5   4.1   16.9  62.5    -0.8   1102  5.6
 17500  -20.0  -4.0   320   19   10   7.5   4.1   16.6  61.8    -1.1   1053  5.4
 17000  -18.8  -1.8   325   19   10   8.0   4.4   16.2  61.2    -1.4   1004  5.1
 16500  -17.6   0.3   325   20   10   7.9   4.4   15.9  60.6    -1.7    953  4.8
 16000  -16.4   2.5   325   20   10   7.9   4.3   15.6  60.1    -2.0    903  4.6
 15500  -15.3   4.5   325   21   11   7.9   4.3   15.3  59.5    -2.3    853  4.3
 15000  -14.1   6.6   325   21   11   7.9   4.3   15.0  58.9    -2.6    803  4.1
 14500  -12.9   8.8   325   22   11   7.8   4.3   14.6  58.3    -2.9    752  3.8
 14000  -11.7  10.9   325   22   11   7.8   4.3   14.3  57.8    -3.2    702  3.6
 13500  -10.6  12.9   325   22   11   7.5   4.1   14.0  57.1    -3.6    654  3.3
 13000   -9.5  14.9   325   22   12   7.4   4.1   13.6  56.5    -3.9    605  3.1
 12500   -8.4  16.9   325   23   12   6.9   3.8   13.2  55.7    -4.4    559  2.8
 12000   -7.4  18.7   325   22   12   6.9   3.8   12.7  54.9    -4.8    513  2.6
 11500   -6.4  20.5   325   22   11   6.5   3.6   12.2  54.0    -5.3    469  2.4
 11000   -5.5  22.1   325   21   11   6.5   3.6   11.7  53.1    -5.8    425  2.2
 10500   -4.5  23.9   325   20   10   6.3   3.4   11.2  52.1    -6.4    382  1.9
 10250   -4.1  24.6   325   20   10   6.2   3.4   10.9  51.6    -6.7    361  1.8
 10000   -3.6  25.5   325   19   10   6.5   3.6   10.6  51.1    -7.0    340  1.7
  9750   -3.1  26.4   320   18    9   6.5   3.6   10.4  50.7    -7.3    318  1.6
  9500   -2.7  27.1   320   17    9   6.4   3.5   10.1  50.2    -7.6    297  1.5
  9250   -2.2  28.0   320   17    9   6.3   3.4    9.8  49.7    -7.9    275  1.4
  9000   -1.7  28.9   320   16    8   7.2   3.9    9.6  49.3    -8.1    254  1.3
  8750   -1.2  29.8   320   14    7   7.4   4.1    9.4  49.0    -8.3    230  1.2
  8500   -0.7  30.7   320   13    7   6.7   3.7    9.2  48.6    -8.6    208  1.1
  8250   -0.2  31.6   315   13    7   7.0   3.8    9.0  48.2    -8.8    185  0.9
  8000    0.4  32.7   315   12    6   8.1   4.4    8.8  47.8    -9.1    162  0.8
  7750    1.0  33.8   315   10    5   8.3   4.6    8.7  47.7    -9.2    135  0.7
  7500    1.6  34.9   315   10    5   7.7   4.2    8.5  47.4    -9.4    111  0.6
  7250    2.2  36.0   315    9    5   8.2   4.5    8.4  47.1    -9.6     86  0.4
  7000    2.8  37.0   310    8    4   9.0   4.9    8.3  47.0    -9.7     59  0.3
  6750    3.5  38.3   310    7    4   8.3   4.5    8.3  46.9    -9.8     32  0.2
  6500    4.0  39.2   310    7    3   7.3   4.0    8.1  46.6   -10.0      8  0.0
  6250    4.5  40.1   305    6    3   6.6   3.6    7.9  46.2   -10.2      M    M
  6000    5.0  41.0   305    5    3   6.1   3.4    7.6  45.7   -10.5      M    M
  5750    5.4  41.7   300    4    2   5.8   3.2    7.3  45.2   -10.8      M    M
  5500    5.5  41.9   290    4    2  -5.7  -3.1    6.7  44.1   -11.5      M    M

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

           02/20/2017 at 0800 MST          |       02/20/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +4.0        | CAPE...     0.0    LI...       +4.6
CINH...     0.0    K Index...  -7.7        | CINH...    -0.3    K Index...  -1.0
                                           |
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 -60.2 -76.4  280  19 10   4.9   2.7 | -61.3 -78.3  270  20 10   4.5   2.4
 45000 -52.5 -62.5  290  27 14   5.0   2.8 | -54.2 -65.6  280  30 16   5.0   2.7
 40000 -44.9 -48.8  305  34 17   5.1   2.8 | -46.7 -52.1  295  36 18   5.0   2.7
 38000 -43.1 -45.6  305  36 18   2.0   1.1 | -44.4 -47.9  300  37 19   3.3   1.8
 36000 -41.9 -43.4  310  37 19   2.0   1.1 | -42.4 -44.3  305  38 20   3.3   1.8
 34000 -40.8 -41.4  310  39 20   1.1   0.6 | -40.7 -41.3  315  40 20   1.0   0.5
 32000 -40.1 -40.2  315  38 19   1.2   0.6 | -39.9 -39.8  315  40 21   1.1   0.6
 30000 -39.1 -38.4  315  36 19   3.4   1.9 | -38.9 -38.0  320  40 21   3.6   2.0
 29000 -38.1 -36.6  315  35 18   3.3   1.8 | -37.8 -36.0  320  40 21   3.7   2.0
 28000 -37.1 -34.8  315  34 17   3.3   1.8 | -36.7 -34.1  320  40 21   3.7   2.0
 27000 -36.1 -33.0  315  32 17   3.2   1.8 | -35.6 -32.1  325  40 21   4.3   2.3
 26000 -34.9 -30.8  315  30 16   4.4   2.4 | -33.9 -29.0  325  39 20   5.7   3.1
 25000 -33.6 -28.5  315  28 14   4.3   2.4 | -32.2 -26.0  325  37 19   5.7   3.1
 24000 -32.3 -26.1  315  26 13   4.3   2.3 | -30.5 -22.9  325  36 19   5.7   3.1
 23000 -30.8 -23.4  320  24 13   5.3   2.9 | -28.7 -19.7  325  33 17   6.0   3.3
 22000 -29.2 -20.6  320  23 12   5.3   2.9 | -26.9 -16.4  325  30 16   6.0   3.3
 21000 -27.7 -17.9  320  22 11   5.5   3.0 | -25.1 -13.2  325  27 14   6.0   3.3
 20000 -25.7 -14.3  320  22 11   6.8   3.7 | -23.4 -10.1  320  24 12   6.0   3.3
 19500 -24.7 -12.5  320  21 11   6.8   3.7 | -22.5  -8.5  320  23 12   6.0   3.3
 19000 -23.7 -10.7  320  21 11   6.8   3.7 | -21.6  -6.9  320  21 11   6.0   3.3
 18500 -22.7  -8.9  320  21 11   6.8   3.7 | -20.7  -5.3  320  20 10   6.0   3.3
 18000 -21.6  -6.9  320  20 11   7.7   4.2 | -19.8  -3.6  315  19 10   5.8   3.2
 17500 -20.4  -4.7  320  20 10   7.6   4.2 | -18.5  -1.3  315  17  9   6.2   3.4
 17000 -18.7  -1.7  320  19 10   7.9   4.3 | -17.5   0.5  315  17  9   7.0   3.9
 16500 -17.5   0.5  320  19 10   7.9   4.3 | -16.4   2.5  320  17  9   7.0   3.9
 16000 -16.3   2.7  320  19 10   8.1   4.4 | -15.4   4.3  320  17  9   7.3   4.0
 15500 -15.1   4.8  325  19 10   8.1   4.4 | -14.3   6.3  320  17  9   7.3   4.0
 15000 -13.9   7.0  325  19 10   7.7   4.2 | -13.2   8.2  320  17  9   7.4   4.1
 14500 -12.8   9.0  325  19 10   7.6   4.2 | -12.1  10.2  325  17  9   7.4   4.1
 14000 -11.7  10.9  330  19 10   7.5   4.1 | -11.0  12.2  325  17  9   7.5   4.1
 13500 -10.6  12.9  330  19 10   7.5   4.1 |  -9.9  14.2  325  17  8   7.6   4.2
 13000  -9.4  15.1  330  19 10   7.5   4.1 |  -8.8  16.2  325  16  8   7.5   4.1
 12500  -8.3  17.1  330  19 10   7.6   4.1 |  -7.7  18.1  325  16  8   7.4   4.1
 12000  -7.2  19.0  330  20 10   7.5   4.1 |  -6.5  20.3  325  15  8   7.3   4.0
 11500  -6.1  21.0  330  19 10   7.4   4.1 |  -5.5  22.1  325  15  8   7.3   4.0
 11000  -5.0  23.0  335  19 10   7.3   4.0 |  -4.4  24.1  325  14  7   7.1   3.9
 10500  -3.9  25.0  330  18  9   7.1   3.9 |  -3.4  25.9  320  13  7   7.0   3.8
 10250  -3.4  25.9  330  18  9   7.4   4.0 |  -2.9  26.8  320  13  7   7.0   3.9
 10000  -2.9  26.8  330  18  9   6.5   3.6 |  -2.3  27.9  320  12  6   7.1   3.9
  9750  -2.4  27.7  330  17  9   6.3   3.4 |  -1.8  28.8  320  12  6   7.1   3.9
  9500  -1.9  28.6  330  17  9   7.0   3.8 |  -1.3  29.7  320  11  6   7.2   3.9
  9250  -1.4  29.5  325  16  8   6.8   3.7 |  -0.8  30.6  320  11  6   6.9   3.8
  9000  -1.0  30.2  325  16  8   6.3   3.4 |  -0.3  31.5  320  10  5   6.7   3.7
  8750  -0.5  31.1  325  15  8   5.4   3.0 |   0.2  32.4  320   9  5   7.1   3.9
  8500  -0.2  31.6  320  15  8   5.5   3.0 |   0.8  33.4  315   9  5   7.4   4.1
  8250   0.2  32.4  315  14  7   5.1   2.8 |   1.3  34.3  315   8  4   7.1   3.9
  8000   0.6  33.1  315  13  7   4.4   2.4 |   1.8  35.2  315   7  4   6.8   3.7
  7750   0.9  33.6  310  13  7   5.1   2.8 |   2.3  36.1  315   7  3   7.1   3.9
  7500   1.3  34.3  310  12  6   5.7   3.2 |   2.8  37.0  310   6  3   7.5   4.1
  7250   1.7  35.1  305  11  6   5.8   3.2 |   3.4  38.1  310   5  3   8.7   4.8
  7000   2.1  35.8  300  10  5   5.8   3.2 |   4.1  39.4  310   4  2   9.2   5.0
  6750   2.6  36.7  300   9  5   6.4   3.5 |   4.8  40.6  310   4  2   9.9   5.5
  6500   3.0  37.4  295   8  4   6.0   3.3 |   5.6  42.1  305   4  2  10.3   5.7
  6250   3.4  38.1  290   7  4   4.3   2.4 |   6.3  43.3  305   3  2   9.9   5.5
  6000   3.7  38.7  285   6  3   4.5   2.5 |   7.0  44.6  305   3  2   9.3   5.1
  5750   4.0  39.2  270   5  2   3.3   1.8 |   7.8  46.0  305   3  1  12.1   6.6
  5500   4.1  39.4  260   4  2  -1.8  -1.0 |   9.0  48.2  305   3  1  20.9  11.4

           02/20/2017 at 1400 MST          |       02/20/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +4.6        | CAPE...     0.0    LI...       +4.4
CINH...     0.0    K Index...  +2.0        | CINH...    -0.1    K Index...  +0.2
                                           |
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  270  21 11   4.2   2.3 | -63.3 -81.9  275  22 12   3.5   1.9
 45000 -55.5 -67.9  280  32 16   4.8   2.6 | -57.5 -71.5  280  33 17   5.5   3.0
 40000 -48.3 -54.9  290  40 20   4.7   2.6 | -49.3 -56.7  295  42 22   5.5   3.0
 38000 -45.9 -50.6  295  40 21   3.8   2.1 | -46.3 -51.3  295  45 23   4.8   2.6
 36000 -43.6 -46.5  305  40 21   3.8   2.1 | -43.4 -46.1  300  47 24   4.8   2.6
 34000 -41.5 -42.7  310  40 21   2.6   1.4 | -40.8 -41.4  305  46 24   2.3   1.3
 32000 -39.7 -39.5  315  41 21   2.6   1.4 | -39.4 -38.9  310  42 22   2.3   1.3
 30000 -38.0 -36.4  320  41 21   3.4   1.9 | -37.8 -36.0  315  39 20   3.5   1.9
 29000 -37.0 -34.6  320  41 21   3.4   1.9 | -36.7 -34.1  315  37 19   3.5   1.9
 28000 -36.0 -32.8  320  41 21   3.4   1.9 | -35.7 -32.3  315  34 18   3.5   1.9
 27000 -35.0 -31.0  320  41 21   4.9   2.7 | -34.5 -30.1  315  33 17   5.5   3.0
 26000 -33.2 -27.8  325  40 21   6.1   3.3 | -32.7 -26.9  315  32 16   6.1   3.3
 25000 -31.3 -24.3  325  39 20   6.1   3.4 | -30.9 -23.6  310  31 16   6.1   3.3
 24000 -29.5 -21.1  325  39 20   6.3   3.4 | -29.1 -20.4  310  30 15   6.6   3.6
 23000 -27.5 -17.5  325  37 19   6.8   3.7 | -27.0 -16.6  310  28 15   7.3   4.0
 22000 -25.5 -13.9  330  35 18   6.8   3.7 | -24.8 -12.6  310  27 14   7.3   4.0
 21000 -23.4 -10.1  330  33 17   6.5   3.6 | -22.7  -8.9  315  25 13   6.6   3.6
 20000 -21.5  -6.7  330  28 14   6.3   3.4 | -20.7  -5.3  320  23 12   6.4   3.5
 19500 -20.6  -5.1  330  25 13   6.3   3.4 | -19.8  -3.6  320  23 12   6.4   3.5
 19000 -19.6  -3.3  325  23 12   6.3   3.4 | -18.3  -0.9  325  21 11   6.4   3.5
 18500 -18.7  -1.7  325  20 10   6.0   3.3 | -17.3   0.9  330  20 10   7.4   4.0
 18000 -17.5   0.5  325  18  9   5.6   3.0 | -16.2   2.8  330  19 10   7.3   4.0
 17500 -16.6   2.1  320  17  9   5.7   3.1 | -15.1   4.8  330  17  9   7.0   3.9
 17000 -15.8   3.6  320  16  8   5.9   3.2 | -14.1   6.6  325  15  8   6.9   3.8
 16500 -14.9   5.2  320  15  8   6.0   3.3 | -13.0   8.6  320  14  7   6.7   3.7
 16000 -13.9   7.0  315  14  7   6.7   3.7 | -12.1  10.2  320  12  6   6.1   3.4
 15500 -13.0   8.6  315  14  7   6.6   3.6 | -11.2  11.8  320  11  6   6.1   3.3
 15000 -11.9  10.6  315  13  7   7.3   4.0 | -10.2  13.6  315  10  5   6.9   3.8
 14500 -10.9  12.4  315  13  7   7.3   4.0 |  -9.2  15.4  315   9  5   6.7   3.7
 14000  -9.8  14.4  310  13  6   7.4   4.1 |  -8.2  17.2  310   9  4   7.6   4.2
 13500  -8.7  16.3  310  12  6   7.5   4.1 |  -7.0  19.4  305   8  4   7.7   4.2
 13000  -7.6  18.3  305  12  6   7.3   4.0 |  -5.9  21.4  305   8  4   7.9   4.3
 12500  -6.5  20.3  305  12  6   7.3   4.0 |  -4.7  23.5  300   9  5   7.9   4.3
 12000  -5.4  22.3  300  12  6   7.5   4.1 |  -3.5  25.7  300   9  5   7.4   4.1
 11500  -4.3  24.3  300  11  6   7.6   4.2 |  -2.5  27.5  295  10  5   7.2   4.0
 11000  -3.2  26.2  295  11  6   7.7   4.2 |  -1.4  29.5  290  10  5   7.2   4.0
 10500  -2.0  28.4  295  10  5   8.1   4.4 |  -0.4  31.3  290   9  5   7.3   4.0
 10250  -1.5  29.3  295  10  5   6.6   3.6 |   0.1  32.2  285   9  5   6.7   3.7
 10000  -1.0  30.2  290  10  5   7.0   3.8 |   0.6  33.1  285   9  5   7.1   3.9
  9750  -0.4  31.3  290   9  5   8.8   4.8 |   1.2  34.2  285   8  4   8.0   4.4
  9500   0.2  32.4  290   8  4   8.3   4.6 |   1.8  35.2  280   8  4   7.9   4.3
  9250   0.8  33.4  290   8  4   8.4   4.6 |   2.3  36.1  280   7  4   7.5   4.1
  9000   1.5  34.7  290   7  3   8.8   4.8 |   2.9  37.2  280   7  3   7.8   4.3
  8750   2.1  35.8  290   6  3   9.5   5.2 |   3.5  38.3  280   6  3   8.7   4.8
  8500   2.9  37.2  290   6  3   9.6   5.3 |   4.2  39.6  275   6  3   8.8   4.8
  8250   3.6  38.5  295   5  3   9.5   5.2 |   4.8  40.6  275   5  3   8.7   4.8
  8000   4.3  39.7  295   5  3   9.5   5.2 |   5.4  41.7  275   5  2   8.7   4.8
  7750   5.0  41.0  295   5  2  10.1   5.5 |   6.1  43.0  275   4  2   9.1   5.0
  7500   5.8  42.4  295   5  2  10.3   5.6 |   6.8  44.2  275   4  2   9.4   5.1
  7250   6.5  43.7  295   5  2   9.8   5.4 |   7.5  45.5  275   4  2   9.6   5.3
  7000   7.3  45.1  295   4  2   9.6   5.3 |   8.2  46.8  275   4  2   9.8   5.4
  6750   8.0  46.4  295   4  2  10.0   5.5 |   9.0  48.2  275   3  2   9.6   5.3
  6500   8.7  47.7  295   4  2  10.3   5.6 |   9.7  49.5  275   3  2   9.8   5.3
  6250   9.5  49.1  295   4  2  10.5   5.7 |  10.4  50.7  275   3  2   9.9   5.4
  6000  10.3  50.5  300   4  2   9.9   5.4 |  11.2  52.2  280   3  1  10.2   5.6
  5750  11.1  52.0  300   3  2  12.0   6.6 |  11.9  53.4  280   3  1   8.9   4.9
  5500  12.2  54.0  300   3  2  19.8  10.8 |  12.4  54.3  280   2  1   5.9   3.2
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

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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