Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 170211
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
2011 MDT Monday, April 16, 2018

This forecast is for Tuesday, April 17, 2018:

If the trigger temperature of 66.5 F/19.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 91 ft/min (0.5 m/s)
   Maximum height of thermals.................. 7014 ft MSL (1665 ft AGL)

Forecast maximum temperature................... 61.0 F/16.6 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 5832 ft MSL (483 ft AGL)
Thermal soaring outlook for Wednesday 04/18.... 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)................ Neither
Potential height of wave....................... 24071 ft MSL (18722 ft AGL)
Wave soaring outlook for Wednesday 04/18....... Poor

Remarks... None

Sunrise/Sunset.................... 06:18:28 / 19:39:30 MDT
Total possible sunshine........... 13 hr 21 min 2 sec (801 min 2 sec)
Altitude of sun at 12:58:59 MDT... 60.89 degrees

Upper air data from numerical model forecast valid on 04/17/2018 at 0600 MDT

Freezing level.................. 13015 ft MSL (7666 ft AGL)
Convective condensation level... 20683 ft MSL (15334 ft AGL)
Lifted condensation level....... 16640 ft MSL (11291 ft AGL)
Lifted index.................... +7.4
K index......................... -5.9

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  -60.3 -76.5   235   36   19   1.4   0.8      M     M       M      M    M
 45000  -58.2 -72.8   235   37   19   1.5   0.8      M     M       M      M    M
 40000  -55.9 -68.6   235   41   21   1.5   0.8      M     M       M      M    M
 38000  -54.6 -66.3   235   42   22   2.9   1.6      M     M       M      M    M
 36000  -52.6 -62.7   235   43   22   2.9   1.6      M     M       M      M    M
 34000  -50.3 -58.5   235   43   22   6.5   3.6      M     M       M      M    M
 32000  -46.3 -51.3   230   41   21   6.6   3.6      M     M       M      M    M
 30000  -42.0 -43.6   230   38   20   8.2   4.5   33.0  91.5    12.8      M    M
 29000  -39.6 -39.3   230   37   19   8.2   4.5   32.3  90.2    12.4      M    M
 28000  -37.1 -34.8   230   36   18   8.2   4.5   31.8  89.2    12.1      M    M
 27000  -34.6 -30.3   230   35   18   8.1   4.4   31.3  88.4    11.9      M    M
 26000  -32.2 -26.0   230   34   17   8.0   4.4   30.5  87.0    11.4      M    M
 25000  -29.8 -21.6   230   33   17   8.0   4.4   29.9  85.8    11.0      M    M
 24000  -27.4 -17.3   230   32   16   8.0   4.4   29.3  84.8    10.7      M    M
 23000  -25.1 -13.2   225   31   16   7.8   4.3   28.6  83.4    10.2      M    M
 22000  -22.7  -8.9   225   29   15   7.8   4.3   27.9  82.2     9.7      M    M
 21000  -20.4  -4.7   220   28   15   8.3   4.6   27.3  81.1     9.4      M    M
 20000  -17.1   1.2   220   27   14   8.9   4.9   26.8  80.2     9.1      M    M
 19500  -15.8   3.6   215   27   14   8.9   4.9   26.7  80.0     9.0      M    M
 19000  -14.4   6.1   215   26   14   8.9   4.9   26.5  79.8     8.9      M    M
 18500  -13.1   8.4   215   26   13   8.8   4.9   26.4  79.6     8.9      M    M
 18000  -11.8  10.8   210   25   13   8.8   4.8   26.3  79.3     8.8      M    M
 17500  -10.5  13.1   210   24   13   8.8   4.8   26.1  79.0     8.7      M    M
 17000   -9.2  15.4   205   24   12   8.8   4.8   25.9  78.7     8.6      M    M
 16500   -7.8  18.0   200   23   12   8.9   4.9   25.8  78.4     8.5      M    M
 16000   -6.6  20.1   200   22   11   8.0   4.4   25.6  78.1     8.3      M    M
 15500   -5.4  22.3   200   21   11   7.9   4.3   25.3  77.5     8.1      M    M
 15000   -4.2  24.4   195   21   11   7.5   4.1   25.0  76.9     7.9      M    M
 14500   -3.1  26.4   200   20   10   7.1   3.9   24.5  76.1     7.5      M    M
 14000   -2.1  28.2   200   20   10   7.1   3.9   24.1  75.4     7.1      M    M
 13500   -1.0  30.2   200   20   10   7.3   4.0   23.7  74.6     6.8      M    M
 13000    0.1  32.2   200   20   10   7.3   4.0   23.3  73.9     6.4      M    M
 12500    1.1  34.0   205   20   10   7.0   3.8   22.8  73.1     6.0      M    M
 12000    2.2  36.0   210   20   10   7.1   3.9   22.4  72.3     5.7      M    M
 11500    3.1  37.6   210   20   10   6.0   3.3   21.9  71.4     5.2      M    M
 11000    4.0  39.2   215   21   11   6.1   3.4   21.3  70.3     4.6      M    M
 10500    4.9  40.8   220   21   11   5.3   2.9   20.7  69.2     4.1      M    M
 10250    5.3  41.5   220   21   11   5.8   3.2   20.3  68.6     3.7      M    M
 10000    5.7  42.3   220   20   11   6.2   3.4   20.0  68.1     3.5      M    M
  9750    6.2  43.2   225   20   10   6.9   3.8   19.8  67.6     3.2      M    M
  9500    6.7  44.1   225   20   10   7.5   4.1   19.6  67.2     3.0      M    M
  9250    7.3  45.1   225   20   10   7.5   4.1   19.4  66.9     2.9      M    M
  9000    7.8  46.0   225   19   10   6.8   3.7   19.2  66.6     2.7      M    M
  8750    8.3  46.9   225   19   10   6.7   3.7   19.0  66.1     2.5      M    M
  8500    8.9  48.0   230   19   10   7.1   3.9   18.7  65.7     2.3      M    M
  8250    9.4  48.9   230   19   10   7.4   4.1   18.5  65.4     2.1      M    M
  8000    9.9  49.8   230   19   10   5.6   3.1   18.3  65.0     1.9      M    M
  7750   10.2  50.4   230   19   10   3.6   2.0   17.9  64.2     1.4      M    M
  7500   10.5  50.9   230   18    9   4.0   2.2   17.4  63.4     1.0      M    M
  7250   10.8  51.4   230   18    9   3.9   2.2   17.0  62.6     0.6      M    M
  7000   11.1  52.0   230   18    9   3.9   2.1   16.6  61.8     0.1      M    M
  6750   11.3  52.3   230   16    8   2.7   1.5   16.1  60.9    -0.4     80  0.4
  6500   11.5  52.7   225   15    8   2.0   1.1   15.5  59.9    -1.0     69  0.3
  6250   11.6  52.9   225   13    7   1.9   1.1   14.9  58.8    -1.6     57  0.3
  6000   11.7  53.1   220   12    6   1.9   1.0   14.3  57.8    -2.2     46  0.2
  5750   11.7  53.1   215   10    5  -3.8  -2.1   13.6  56.5    -2.9     39  0.2
  5500   11.0  51.8   205    7    3 -13.9  -7.7   12.1  53.9    -4.4     54  0.3

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

           04/17/2018 at 0900 MDT          |       04/17/2018 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +7.1        | CAPE...     0.0    LI...       +5.3
CINH...    -0.0    K Index... -18.5        | CINH...    -0.2    K Index...  -0.5
                                           |
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 -59.8 -75.6  240  37 19  -0.2  -0.1 | -57.4 -71.3  245  35 18  -0.8  -0.4
 45000 -60.1 -76.2  235  38 20   1.2   0.6 | -58.5 -73.3  235  43 22   0.6   0.3
 40000 -57.2 -71.0  230  39 20   1.9   1.0 | -55.6 -68.1  225  41 21   2.0   1.1
 38000 -55.3 -67.5  230  39 20   4.5   2.5 | -53.7 -64.7  225  41 21   4.6   2.5
 36000 -52.6 -62.7  225  39 20   4.5   2.5 | -50.9 -59.6  225  41 21   4.6   2.5
 34000 -49.1 -56.4  225  39 20   6.7   3.7 | -47.6 -53.7  225  41 21   6.2   3.4
 32000 -45.1 -49.2  225  39 20   6.8   3.7 | -43.9 -47.0  225  43 22   6.1   3.4
 30000 -40.8 -41.4  225  39 20   7.8   4.3 | -40.2 -40.4  225  44 22   6.8   3.7
 29000 -38.5 -37.3  225  39 20   7.8   4.3 | -38.2 -36.8  225  44 23   6.8   3.7
 28000 -36.1 -33.0  225  39 20   7.8   4.3 | -36.1 -33.0  225  44 23   6.8   3.7
 27000 -33.8 -28.8  225  38 20   8.0   4.4 | -34.1 -29.4  225  45 23   6.7   3.7
 26000 -31.3 -24.3  225  38 20   8.3   4.5 | -31.9 -25.4  225  46 23   7.6   4.2
 25000 -28.9 -20.0  225  38 20   8.3   4.5 | -29.6 -21.3  225  46 24   7.6   4.2
 24000 -26.4 -15.5  225  38 19   8.3   4.5 | -27.3 -17.1  225  47 24   7.6   4.2
 23000 -24.0 -11.2  225  37 19   7.9   4.3 | -25.1 -13.2  225  47 24   7.1   3.9
 22000 -21.6  -6.9  225  37 19   7.9   4.3 | -23.0  -9.4  225  47 24   7.1   3.9
 21000 -19.2  -2.6  225  37 19   7.8   4.3 | -20.8  -5.4  230  47 24   7.4   4.1
 20000 -17.0   1.4  225  37 19   7.5   4.1 | -19.2  -2.6  230  45 23   4.9   2.7
 19500 -15.9   3.4  225  36 19   7.5   4.1 | -18.5  -1.3  230  44 23   4.9   2.7
 19000 -14.2   6.4  225  36 19   7.5   4.1 | -17.8  -0.0  230  43 22   4.9   2.7
 18500 -13.1   8.4  225  36 19   7.2   3.9 | -17.0   1.4  230  43 22   5.0   2.7
 18000 -12.0  10.4  225  36 18   6.9   3.8 | -16.1   3.0  230  40 21   3.3   1.8
 17500 -11.0  12.2  225  36 18   6.9   3.8 | -15.6   3.9  230  39 20   3.3   1.8
 17000 -10.0  14.0  225  35 18   6.3   3.5 | -15.1   4.8  230  37 19   3.8   2.1
 16500  -9.1  15.6  225  35 18   6.4   3.5 | -14.5   5.9  230  34 18   3.9   2.1
 16000  -8.2  17.2  225  34 18   5.8   3.2 | -14.0   6.8  235  32 16   4.5   2.4
 15500  -7.3  18.9  225  33 17   5.5   3.0 | -13.2   8.2  235  29 15   5.2   2.9
 15000  -6.5  20.3  225  32 16   5.5   3.0 | -12.5   9.5  235  27 14   5.6   3.0
 14500  -5.7  21.7  225  30 16   5.7   3.2 | -11.4  11.5  235  25 13   8.1   4.5
 14000  -4.9  23.2  225  29 15   5.8   3.2 | -10.2  13.6  235  23 12   7.8   4.3
 13500  -3.9  25.0  225  27 14   7.0   3.8 |  -8.9  16.0  235  22 11   9.6   5.3
 13000  -2.9  26.8  225  26 14   6.9   3.8 |  -7.5  18.5  235  21 11   9.5   5.2
 12500  -1.9  28.6  225  26 13   7.2   4.0 |  -6.1  21.0  235  21 11   9.7   5.3
 12000  -0.8  30.6  225  25 13   7.2   4.0 |  -4.6  23.7  240  20 10   9.6   5.3
 11500   0.3  32.5  225  25 13   6.9   3.8 |  -3.2  26.2  240  20 10   9.8   5.4
 11000   1.3  34.3  225  25 13   6.9   3.8 |  -1.7  28.9  240  19 10   9.9   5.4
 10500   2.3  36.1  230  25 13   5.6   3.1 |  -0.3  31.5  240  19 10   8.6   4.7
 10250   2.7  36.9  230  25 13   6.8   3.7 |   0.4  32.7  240  19 10   9.5   5.2
 10000   3.3  37.9  230  25 13   8.8   4.8 |   1.1  34.0  240  19 10  11.2   6.1
  9750   4.0  39.2  230  24 12   8.7   4.8 |   2.0  35.6  240  19 10  11.2   6.1
  9500   4.6  40.3  230  24 12   8.2   4.5 |   2.8  37.0  240  18  9  10.5   5.8
  9250   5.2  41.4  230  24 12   8.4   4.6 |   3.6  38.5  240  18  9  11.1   6.1
  9000   5.8  42.4  230  24 12   7.3   4.0 |   4.4  39.9  240  18  9   8.4   4.6
  8750   6.3  43.3  230  24 12   6.7   3.7 |   4.9  40.8  240  18  9   8.0   4.4
  8500   6.8  44.2  230  23 12   7.4   4.1 |   5.7  42.3  240  18  9  10.2   5.6
  8250   7.4  45.3  230  23 12   7.0   3.8 |   6.4  43.5  240  18  9   9.5   5.2
  8000   7.9  46.2  230  22 11   7.9   4.3 |   7.1  44.8  240  17  9  10.3   5.6
  7750   8.5  47.3  230  21 11   8.6   4.7 |   7.9  46.2  240  17  9  10.4   5.7
  7500   9.2  48.6  230  20 10   8.1   4.5 |   8.7  47.7  240  17  9   9.9   5.4
  7250   9.8  49.6  225  19 10   8.5   4.7 |   9.4  48.9  240  16  8  10.4   5.7
  7000  10.4  50.7  225  18  9   7.5   4.1 |  10.2  50.4  240  16  8   8.9   4.9
  6750  10.9  51.6  225  18  9   8.7   4.8 |  10.8  51.4  240  16  8   9.7   5.3
  6500  11.7  53.1  225  17  9  10.6   5.8 |  11.6  52.9  240  16  8  11.6   6.4
  6250  12.5  54.5  225  15  8  10.1   5.6 |  12.5  54.5  240  15  8  11.3   6.2
  6000  13.2  55.8  225  14  7  10.0   5.5 |  13.3  55.9  240  15  8  10.0   5.5
  5750  14.0  57.2  220  13  7  11.6   6.4 |  14.2  57.6  240  14  7  16.1   8.8
  5500  15.0  59.0  220  11  6  15.2   8.3 |  15.9  60.6  240  12  6  30.1  16.5

           04/17/2018 at 1500 MDT          |       04/17/2018 at 1800 MDT
                                           |
CAPE...   +21.5    LI...       +0.6        | CAPE...    +4.9    LI...       +0.9
CINH...    -1.7    K Index...  +7.3        | CINH...    -2.4    K Index...  +2.5
                                           |
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 -54.9 -66.8  240  32 17  -0.4  -0.2 | -54.2 -65.6  240  31 16   0.9   0.5
 45000 -55.6 -68.1  240  44 23   0.3   0.2 | -52.8 -63.0  245  42 21   0.9   0.5
 40000 -51.9 -61.4  235  42 22   2.5   1.4 | -51.0 -59.8  250  39 20   1.3   0.7
 38000 -50.0 -58.0  235  42 22   4.2   2.3 | -49.5 -57.1  255  40 20   3.4   1.9
 36000 -47.2 -53.0  235  43 22   4.2   2.3 | -47.5 -53.5  255  41 21   3.4   1.9
 34000 -44.6 -48.3  240  44 23   4.4   2.4 | -45.5 -49.9  260  43 22   4.0   2.2
 32000 -42.0 -43.6  240  47 24   4.4   2.4 | -42.7 -44.9  260  44 23   4.6   2.5
 30000 -39.3 -38.7  240  50 26   5.2   2.8 | -39.9 -39.8  260  45 23   4.8   2.7
 29000 -37.6 -35.7  235  50 26   5.6   3.1 | -38.3 -36.9  265  44 23   5.4   2.9
 28000 -35.9 -32.6  235  50 26   5.6   3.1 | -36.7 -34.1  265  44 23   5.4   2.9
 27000 -34.2 -29.6  235  51 26   5.6   3.1 | -35.1 -31.2  265  44 22   5.3   2.9
 26000 -32.8 -27.0  235  49 25   4.1   2.2 | -34.1 -29.4  265  42 21  -0.3  -0.2
 25000 -31.6 -24.9  235  47 24   4.1   2.2 | -34.1 -29.4  265  37 19   0.0   0.0
 24000 -30.3 -22.5  235  44 23   4.0   2.2 | -34.1 -29.4  265  33 17  -0.0  -0.0
 23000 -29.4 -20.9  235  41 21   1.5   0.8 | -33.9 -29.0  265  28 15   2.7   1.5
 22000 -28.9 -20.0  240  35 18   1.7   0.9 | -33.2 -27.8  265  24 12   2.4   1.3
 21000 -28.4 -19.1  245  30 15   1.7   0.9 | -32.5 -26.5  265  20 10   2.6   1.4
 20000 -27.3 -17.1  245  25 13   5.5   3.0 | -30.5 -22.9  270  17  9   7.2   3.9
 19500 -26.4 -15.5  250  24 12   5.7   3.1 | -29.4 -20.9  275  17  9   7.1   3.9
 19000 -25.6 -14.1  250  22 11   5.7   3.1 | -28.4 -19.1  275  16  8   7.1   3.9
 18500 -24.3 -11.7  255  20 10   5.5   3.0 | -27.3 -17.1  280  16  8   6.9   3.8
 18000 -23.3  -9.9  255  19 10   7.7   4.2 | -26.1 -15.0  280  16  8   8.9   4.9
 17500 -22.2  -8.0  260  18  9   7.5   4.1 | -24.8 -12.6  280  16  8   8.7   4.8
 17000 -21.1  -6.0  260  18  9   7.7   4.2 | -23.5 -10.3  285  16  8   8.7   4.8
 16500 -20.0  -4.0  265  18  9   7.8   4.3 | -22.2  -8.0  285  16  8   8.7   4.7
 16000 -18.8  -1.8  265  17  9   7.8   4.3 | -20.9  -5.6  290  16  8   8.7   4.7
 15500 -17.6   0.3  265  17  9   8.0   4.4 | -19.7  -3.5  290  16  8   8.7   4.7
 15000 -16.4   2.5  265  17  9   8.0   4.4 | -18.4  -1.1  295  16  8   8.7   4.8
 14500 -15.2   4.6  270  17  9   7.9   4.3 | -17.1   1.2  295  17  9   8.8   4.8
 14000 -14.1   6.6  270  18  9   7.8   4.3 | -15.8   3.6  300  17  9   8.8   4.8
 13500 -12.8   9.0  270  18  9   8.8   4.8 | -14.5   5.9  300  18  9   8.5   4.7
 13000 -11.5  11.3  270  18  9   8.7   4.8 | -13.2   8.2  300  18  9   8.5   4.7
 12500 -10.3  13.5  270  18 10   8.6   4.7 | -11.9  10.6  300  19 10   8.6   4.7
 12000  -9.0  15.8  270  19 10   8.5   4.7 | -10.6  12.9  300  20 10   8.7   4.8
 11500  -7.7  18.1  275  19 10   9.2   5.0 |  -9.4  15.1  300  20 10   7.9   4.4
 11000  -6.3  20.7  275  19 10   9.3   5.1 |  -8.2  17.2  300  21 11   8.1   4.4
 10500  -5.0  23.0  275  18 10   7.9   4.4 |  -7.1  19.2  300  21 11   7.0   3.8
 10250  -4.4  24.1  275  18  9   7.9   4.3 |  -6.6  20.1  300  21 11   6.4   3.5
 10000  -3.7  25.3  275  18  9  11.7   6.4 |  -6.0  21.2  300  21 11   9.2   5.1
  9750  -2.7  27.1  275  18  9  12.2   6.7 |  -5.2  22.6  295  21 11   9.8   5.4
  9500  -2.0  28.4  275  18  9   9.5   5.2 |  -4.7  23.5  295  20 10   7.2   3.9
  9250  -1.2  29.8  275  18  9  10.5   5.7 |  -4.1  24.6  295  20 10   8.1   4.5
  9000  -0.5  31.1  280  18  9   9.3   5.1 |  -3.5  25.7  295  20 10   7.0   3.8
  8750   0.2  32.4  280  18  9   9.2   5.0 |  -3.0  26.6  295  19 10   8.7   4.8
  8500   0.9  33.6  280  18  9   9.9   5.4 |  -2.2  28.0  290  19 10  10.9   6.0
  8250   1.7  35.1  280  18  9  10.0   5.5 |  -1.4  29.5  290  19 10  10.4   5.7
  8000   2.4  36.3  280  18  9   8.9   4.9 |  -0.7  30.7  290  19 10  10.2   5.6
  7750   3.0  37.4  280  17  9   9.4   5.2 |   0.1  32.2  290  18  9   9.6   5.3
  7500   3.8  38.8  280  17  9  10.8   5.9 |   0.8  33.4  290  18  9   9.4   5.1
  7250   4.6  40.3  280  17  9  10.6   5.8 |   1.5  34.7  290  18  9   9.8   5.4
  7000   5.4  41.7  280  17  9   8.7   4.7 |   2.3  36.1  290  18  9  11.2   6.1
  6750   6.0  42.8  280  17  9   9.7   5.3 |   3.1  37.6  290  17  9  10.4   5.7
  6500   6.9  44.4  280  16  8  12.3   6.8 |   3.8  38.8  290  17  9   9.2   5.0
  6250   7.8  46.0  280  16  8  11.3   6.2 |   4.6  40.3  290  17  9  10.5   5.7
  6000   8.6  47.5  280  16  8  10.9   6.0 |   5.4  41.7  290  16  8  11.5   6.3
  5750   9.4  48.9  280  15  8  10.8   5.9 |   6.2  43.2  290  15  8  10.3   5.6
  5500  10.4  50.7  280  14  7  19.2  10.5 |   7.0  44.6  290  14  7  12.8   7.0
________________________________________________________________________________

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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