Soaring Guidance
Issued by NWS Denver/Boulder, CO

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415
UXUS97 KBOU 030132
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1932 MDT Monday, May 2, 2016

This forecast is for Tuesday, May 3, 2016:

If the trigger temperature of 53.4 F/11.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 769 ft/min (3.9 m/s)
   Maximum height of thermals.................. 14910 ft MSL (9603 ft AGL)

Forecast maximum temperature................... 65.0 F/18.8 C
Time of trigger temperature.................... 1000 MDT
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................. 13127 ft MSL (7820 ft AGL)
Thermal soaring outlook for Wednesday 05/04.... Excellent

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....................... 26416 ft MSL (21109 ft AGL)
Wave soaring outlook for Wednesday 05/04....... Poor

Remarks...

Sunrise/Sunset.................... 05:57:01 / 19:55:22 MDT
Total possible sunshine........... 13 hr 58 min 22 sec (838 min 22 sec)
Altitude of sun at 12:56:22 MDT... 66.19 degrees

Upper air data from numerical model forecast valid on 05/03/2016 at 0600 MDT

Freezing level.................. 9316 ft MSL (4009 ft AGL)
Convective condensation level... 11111 ft MSL (5804 ft AGL)
Lifted condensation level....... 13240 ft MSL (7933 ft AGL)
Lifted index.................... +0.2
K index......................... +5.0

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  -58.0 -72.4   300   29   15   0.4   0.2      M     M       M      M    M
 45000  -57.3 -71.1   305   33   17  -0.2  -0.1      M     M       M      M    M
 40000  -59.0 -74.2   340   28   14  -1.1  -0.6      M     M       M      M    M
 38000  -58.2 -72.8   005   31   16   3.3   1.8      M     M       M      M    M
 36000  -56.2 -69.2   025   41   21   3.3   1.8      M     M       M      M    M
 34000  -53.7 -64.7   035   51   26   7.3   4.0      M     M       M      M    M
 32000  -49.3 -56.7   030   55   28   7.4   4.0      M     M       M      M    M
 30000  -44.7 -48.5   030   57   30   8.2   4.5   31.4  88.5     9.8      M    M
 29000  -42.3 -44.1   025   56   29   8.2   4.5   30.7  87.2     9.4      M    M
 28000  -39.2 -38.6   025   55   28   8.2   4.5   30.0  86.0     9.0      M    M
 27000  -36.7 -34.1   025   54   28   8.5   4.7   29.5  85.1     8.7      M    M
 26000  -34.2 -29.6   020   54   28   8.5   4.7   28.9  84.1     8.4      M    M
 25000  -31.7 -25.1   020   54   28   8.5   4.7   28.5  83.3     8.1      M    M
 24000  -29.1 -20.4   020   54   28   8.9   4.9   28.1  82.6     7.9      M    M
 23000  -26.4 -15.5   015   53   27   9.0   4.9   27.8  82.0     7.7      M    M
 22000  -23.7 -10.7   015   53   27   9.0   5.0   27.5  81.5     7.6      M    M
 21000  -21.2  -6.2   015   52   27   6.2   3.4   27.1  80.7     7.3      M    M
 20000  -19.3  -2.7   015   49   25   6.5   3.6   25.9  78.6     6.4      M    M
 19500  -18.3  -0.9   015   48   25   6.5   3.6   25.3  77.6     5.9      M    M
 19000  -17.3   0.9   015   46   24   6.7   3.6   24.8  76.6     5.5      M    M
 18500  -16.5   2.3   015   44   23   4.8   2.6   24.2  75.5     5.0      M    M
 18000  -15.8   3.6   010   41   21   4.6   2.5   23.3  73.9     4.2      M    M
 17500  -15.1   4.8   005   38   20   5.0   2.8   22.4  72.3     3.5      M    M
 17000  -14.2   6.4   360   37   19   6.1   3.4   21.7  71.1     2.9      M    M
 16500  -13.3   8.1   360   36   18   6.2   3.4   21.1  70.0     2.4      M    M
 16000  -12.5   9.5   355   34   18   5.2   2.9   20.4  68.7     1.8      M    M
 15500  -11.7  10.9   355   34   17   5.3   2.9   19.7  67.4     1.1      M    M
 15000  -10.7  12.7   350   32   16   4.0   2.2   18.4  65.1    -0.1    767  3.9
 14500  -10.1  13.8   350   30   15   4.0   2.2   17.5  63.5    -0.9    734  3.7
 14000   -9.4  15.1   350   28   15   4.6   2.5   16.6  61.8    -1.7    700  3.6
 13500   -8.8  16.2   350   27   14   4.4   2.4   15.7  60.3    -2.6    666  3.4
 13000   -8.0  17.6   355   26   13   6.3   3.4   15.0  59.0    -3.3    629  3.2
 12500   -7.1  19.2   355   25   13   6.2   3.4   14.4  58.0    -3.9    588  3.0
 12000   -6.2  20.8   355   25   13   8.0   4.4   14.0  57.2    -4.4    544  2.8
 11500   -5.0  23.0   355   25   13   8.1   4.4   13.7  56.7    -4.7    494  2.5
 11000   -3.8  25.2   355   25   13   8.4   4.6   13.5  56.3    -5.0    444  2.3
 10500   -2.6  27.3   355   26   13   9.6   5.2   13.2  55.8    -5.3    394  2.0
 10250   -2.0  28.4   355   26   13   3.8   2.1   13.1  55.7    -5.5    369  1.9
 10000   -1.9  28.6   355   26   13   5.0   2.8   12.5  54.5    -6.1    358  1.8
  9750   -1.2  29.8   355   26   13  11.6   6.4   12.5  54.6    -6.1    328  1.7
  9500   -0.4  31.3   355   26   13   9.9   5.4   12.6  54.6    -6.1    299  1.5
  9250    0.2  32.4   355   26   13   7.7   4.2   12.5  54.6    -6.2    271  1.4
  9000    0.7  33.3   360   26   13   6.3   3.5   12.3  54.1    -6.5    250  1.3
  8750    1.2  34.2   360   26   13   8.2   4.5   12.1  53.8    -6.7    227  1.2
  8500    1.8  35.2   360   26   14   8.4   4.6   12.0  53.6    -6.8    202  1.0
  8250    2.4  36.3   360   26   14   8.4   4.6   11.9  53.4    -7.0    176  0.9
  8000    3.0  37.4   360   26   13   8.4   4.6   11.8  53.2    -7.1    151  0.8
  7750    3.6  38.5   005   26   13   9.3   5.1   11.7  53.1    -7.2    125  0.6
  7500    4.3  39.7   005   26   13   9.4   5.1   11.7  53.1    -7.3     96  0.5
  7250    5.0  41.0   005   26   13   8.6   4.7   11.6  52.9    -7.4     69  0.4
  7000    5.6  42.1   005   26   13   9.0   5.0   11.5  52.8    -7.5     42  0.2
  6750    6.3  43.3   005   25   13   8.3   4.6   11.5  52.7    -7.6     15  0.1
  6500    6.8  44.2   360   24   13   5.1   2.8   11.3  52.3    -7.8      M    M
  6250    7.2  45.0   360   23   12   4.6   2.5   10.8  51.5    -8.2      M    M
  6000    7.5  45.5   355   22   11   1.7   0.9   10.4  50.8    -8.6      M    M
  5750    7.2  45.0   350   18    9 -11.8  -6.5    9.4  48.9    -9.7      M    M
  5500    5.8  42.4   335   11    5 -23.5 -12.9    7.3  45.1   -11.8      M    M

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

           05/03/2016 at 0900 MDT          |       05/03/2016 at 1200 MDT
                                           |
K index... -9.5  LI... +4.9                | K index... -22.1  LI... +3.7
CAPE... +1.1  CIN... -2.8                  | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -58.5 -73.3  300  29 15   0.8   0.4 | -58.8 -73.8  300  27 14   0.6   0.4
 45000 -57.3 -71.1  310  32 16  -0.3  -0.1 | -57.8 -72.0  310  28 15  -0.8  -0.4
 40000 -59.7 -75.5  010  25 13  -1.6  -0.9 | -61.3 -78.3  030  25 13  -2.2  -1.2
 38000 -58.6 -73.5  030  31 16   4.2   2.3 | -59.6 -75.3  045  29 15   5.5   3.0
 36000 -56.1 -69.0  040  39 20   4.2   2.3 | -56.3 -69.3  045  32 17   5.5   3.0
 34000 -53.1 -63.6  045  45 23   7.1   3.9 | -52.6 -62.7  050  33 17   7.5   4.1
 32000 -48.8 -55.8  040  43 22   7.2   3.9 | -48.1 -54.6  040  32 16   7.6   4.2
 30000 -44.4 -47.9  035  42 22   8.2   4.5 | -43.0 -45.4  035  30 16   7.4   4.0
 29000 -41.3 -42.3  035  41 21   8.3   4.5 | -40.8 -41.4  035  30 15   7.4   4.0
 28000 -38.8 -37.8  030  40 21   8.3   4.5 | -38.6 -37.5  035  30 15   7.4   4.1
 27000 -36.3 -33.3  030  40 21   8.4   4.6 | -36.2 -33.2  030  29 15   8.8   4.9
 26000 -33.8 -28.8  030  40 21   8.4   4.6 | -33.6 -28.5  030  29 15   8.8   4.8
 25000 -31.3 -24.3  030  40 21   8.4   4.6 | -31.0 -23.8  025  28 14   8.8   4.8
 24000 -28.8 -19.8  030  40 21   8.6   4.7 | -28.4 -19.1  020  28 14   7.9   4.3
 23000 -26.2 -15.2  030  41 21   8.7   4.8 | -26.0 -14.8  025  29 15   8.0   4.4
 22000 -23.6 -10.5  030  42 22   8.7   4.8 | -23.7 -10.7  030  31 16   8.0   4.4
 21000 -21.0  -5.8  030  43 22   8.1   4.4 | -21.2  -6.2  030  32 16   8.8   4.8
 20000 -18.6  -1.5  030  41 21   8.2   4.5 | -18.6  -1.5  035  32 16   8.7   4.8
 19500 -17.4   0.7  030  41 21   8.2   4.5 | -17.3   0.9  035  32 16   8.8   4.8
 19000 -16.2   2.8  035  40 21   8.4   4.6 | -16.0   3.2  035  32 16   8.9   4.9
 18500 -15.1   4.8  035  39 20   5.2   2.8 | -14.8   5.4  035  31 16   6.9   3.8
 18000 -14.3   6.3  035  36 19   5.2   2.9 | -13.7   7.3  035  29 15   7.1   3.9
 17500 -13.5   7.7  035  34 17   4.9   2.7 | -12.7   9.1  035  28 14   5.9   3.3
 17000 -12.9   8.8  030  32 16   4.4   2.4 | -11.9  10.6  030  25 13   5.2   2.8
 16500 -12.2  10.0  030  30 15   4.5   2.4 | -11.1  12.0  025  23 12   5.2   2.8
 16000 -11.6  11.1  025  29 15   3.2   1.7 | -10.3  13.5  025  22 11   5.8   3.2
 15500 -11.1  12.0  025  29 15   3.2   1.7 |  -9.0  15.8  020  21 11   5.1   2.8
 15000 -10.2  13.6  020  28 15   5.0   2.8 |  -8.4  16.9  020  21 11   4.1   2.3
 14500  -9.5  14.9  015  28 14   5.0   2.7 |  -7.7  18.1  015  21 11   4.3   2.3
 14000  -8.7  16.3  015  27 14   5.0   2.7 |  -7.0  19.4  015  21 11   5.0   2.8
 13500  -8.0  17.6  010  27 14   5.1   2.8 |  -6.3  20.7  015  21 11   5.0   2.7
 13000  -7.3  18.9  010  26 13   5.1   2.8 |  -5.5  22.1  015  21 11   5.9   3.2
 12500  -6.6  20.1  005  24 13   5.2   2.9 |  -4.6  23.7  015  20 10   5.8   3.2
 12000  -5.8  21.6  360  23 12   6.4   3.5 |  -3.8  25.2  010  20 10   5.5   3.0
 11500  -4.9  23.2  355  21 11   6.5   3.5 |  -3.0  26.6  010  20 10   5.6   3.1
 11000  -4.0  24.8  355  21 11   7.9   4.3 |  -2.2  28.0  005  20 10   4.8   2.6
 10500  -2.9  26.8  360  20 10   8.6   4.7 |  -1.6  29.1  005  19 10   5.4   2.9
 10250  -2.4  27.7  360  20 10   3.8   2.1 |  -1.3  29.7  360  19 10   2.1   1.2
 10000  -2.3  27.9  360  20 10   5.6   3.1 |  -1.2  29.8  360  19 10   5.1   2.8
  9750  -1.5  29.3  360  20 10  11.7   6.4 |  -0.6  30.9  360  17  9  10.3   5.7
  9500  -0.8  30.6  360  20 10   9.7   5.3 |   0.0  32.0  355  16  8   8.5   4.7
  9250  -0.2  31.6  005  20 10   6.6   3.6 |   0.5  32.9  350  14  7   6.2   3.4
  9000   0.2  32.4  360  20 10   5.8   3.2 |   0.9  33.6  350  14  7   6.8   3.7
  8750   0.8  33.4  360  20 10   9.2   5.0 |   1.5  34.7  350  13  7  10.8   5.9
  8500   1.5  34.7  360  20 10   9.3   5.1 |   2.3  36.1  350  12  6  10.2   5.6
  8250   2.1  35.8  360  21 11   8.1   4.4 |   2.9  37.2  345  12  6   8.3   4.6
  8000   2.8  37.0  360  21 11   8.1   4.4 |   3.5  38.3  345  12  6   8.7   4.7
  7750   3.4  38.1  360  21 11   9.2   5.1 |   4.2  39.6  345  12  6   9.8   5.4
  7500   4.1  39.4  360  22 11   9.3   5.1 |   4.9  40.8  345  11  6  10.3   5.7
  7250   4.8  40.6  360  22 11   8.5   4.7 |   5.7  42.3  345  11  6  10.0   5.5
  7000   5.4  41.7  355  21 11   9.0   5.0 |   6.4  43.5  345  11  6  10.0   5.5
  6750   6.1  43.0  355  21 11   9.2   5.0 |   7.1  44.8  345  11  6   9.9   5.5
  6500   6.8  44.2  355  20 10   6.5   3.6 |   7.9  46.2  345  11  6  10.2   5.6
  6250   7.1  44.8  350  17  9   4.6   2.5 |   8.6  47.5  345  11  5  10.0   5.5
  6000   7.5  45.5  345  15  8   5.5   3.0 |   9.4  48.9  345  10  5  10.9   6.0
  5750   7.9  46.2  340  12  6   6.3   3.5 |  10.3  50.5  340  10  5  15.1   8.3
  5500   8.3  46.9  335   9  5   7.2   3.9 |  11.6  52.9  340  10  5  19.0  10.4

           05/03/2016 at 1500 MDT          |       05/03/2016 at 1800 MDT
                                           |
K index... -15.6  LI... +2.4               | K index... -9.3  LI... +1.5
CAPE... 0.0  CIN... -0.2                   | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -58.9 -74.0  300  28 14   0.5   0.3 | -60.0 -76.0  305  28 15   0.2   0.1
 45000 -58.3 -72.9  310  27 14  -2.5  -1.4 | -59.9 -75.8  315  24 13  -1.4  -0.8
 40000 -61.6 -78.9  035  21 11  -2.2  -1.2 | -61.8 -79.2  030  18  9  -1.1  -0.6
 38000 -59.6 -75.3  040  24 12   6.2   3.4 | -59.3 -74.7  035  21 11   6.5   3.6
 36000 -55.9 -68.6  045  24 13   6.2   3.4 | -55.4 -67.7  035  22 11   6.5   3.6
 34000 -52.0 -61.6  040  24 12   7.4   4.1 | -51.2 -60.2  030  22 11   7.7   4.2
 32000 -47.5 -53.5  035  23 12   7.4   4.1 | -46.6 -51.9  020  20 10   7.7   4.2
 30000 -42.6 -44.7  030  23 12   7.2   4.0 | -41.6 -42.9  015  20 10   7.1   3.9
 29000 -40.4 -40.7  025  23 12   7.2   4.0 | -39.5 -39.1  015  20 11   7.1   3.9
 28000 -38.2 -36.8  025  23 12   7.3   4.0 | -37.4 -35.3  015  21 11   7.1   3.9
 27000 -36.0 -32.8  020  24 12   8.1   4.5 | -35.2 -31.4  015  22 11   7.5   4.1
 26000 -33.5 -28.3  020  24 13   8.1   4.5 | -32.9 -27.2  015  23 12   7.5   4.1
 25000 -31.1 -24.0  020  25 13   8.1   4.5 | -30.7 -23.3  015  24 12   7.5   4.1
 24000 -28.7 -19.7  025  25 13   8.0   4.4 | -28.4 -19.1  020  24 13   8.3   4.6
 23000 -26.3 -15.3  025  26 13   8.0   4.4 | -25.9 -14.6  015  23 12   8.3   4.5
 22000 -23.9 -11.0  030  26 14   8.0   4.4 | -23.5 -10.3  015  22 12   8.3   4.5
 21000 -21.4  -6.5  030  26 13   8.9   4.9 | -21.0  -5.8  015  21 11   8.3   4.6
 20000 -18.8  -1.8  030  25 13   8.9   4.9 | -18.5  -1.3  015  19 10   8.4   4.6
 19500 -17.5   0.5  030  24 12   8.9   4.9 | -17.3   0.9  015  18  9   8.4   4.6
 19000 -16.1   3.0  030  24 12   8.8   4.8 | -16.0   3.2  015  17  9   8.4   4.6
 18500 -14.9   5.2  035  23 12   8.5   4.6 | -14.7   5.5  015  17  9   8.5   4.7
 18000 -13.6   7.5  035  24 12   8.5   4.7 | -13.5   7.7  015  16  8   8.5   4.7
 17500 -12.4   9.7  035  24 12   8.1   4.4 | -12.2  10.0  015  16  8   7.7   4.2
 17000 -11.2  11.8  035  24 12   7.9   4.3 | -11.1  12.0  015  16  8   7.6   4.2
 16500 -10.0  14.0  035  24 12   7.4   4.1 |  -9.5  14.9  010  15  8   7.8   4.3
 16000  -8.5  16.7  030  23 12   5.9   3.2 |  -8.3  17.1  010  15  8   7.9   4.3
 15500  -7.6  18.3  030  23 12   5.5   3.0 |  -7.2  19.0  010  16  8   7.6   4.2
 15000  -6.8  19.8  025  23 12   5.1   2.8 |  -6.0  21.2  010  16  8   7.4   4.0
 14500  -6.1  21.0  025  22 11   5.1   2.8 |  -4.9  23.2  015  16  8   7.2   3.9
 14000  -5.3  22.5  020  21 11   5.1   2.8 |  -3.9  25.0  015  16  8   6.8   3.7
 13500  -4.5  23.9  020  21 11   5.2   2.8 |  -2.8  27.0  010  17  9   6.7   3.7
 13000  -3.7  25.3  015  20 10   5.3   2.9 |  -1.9  28.6  010  17  9   6.0   3.3
 12500  -2.9  26.8  015  19 10   5.3   2.9 |  -0.9  30.4  010  17  9   6.0   3.3
 12000  -2.1  28.2  010  18  9   6.1   3.4 |  -0.0  32.0  005  16  8   6.0   3.3
 11500  -1.1  30.0  010  16  8   6.1   3.4 |   0.9  33.6  005  16  8   6.0   3.3
 11000  -0.2  31.6  005  15  8   5.8   3.2 |   1.8  35.2  360  16  8   6.1   3.4
 10500   0.6  33.1  360  14  7   5.8   3.2 |   2.8  37.0  355  15  8   5.8   3.2
 10250   0.9  33.6  355  14  7   2.8   1.5 |   3.1  37.6  355  15  8   3.2   1.8
 10000   1.1  34.0  355  13  7   5.4   3.0 |   3.4  38.1  355  15  8   5.8   3.2
  9750   1.7  35.1  355  12  6  10.0   5.5 |   4.0  39.2  355  14  7   9.6   5.3
  9500   2.3  36.1  355  11  6   8.6   4.7 |   4.6  40.3  360  13  7   7.8   4.3
  9250   2.8  37.0  355  10  5   6.5   3.5 |   5.1  41.2  360  12  6   5.3   2.9
  9000   3.2  37.8  355   9  5   6.9   3.8 |   5.4  41.7  360  11  5   5.3   2.9
  8750   3.7  38.7  350   9  5   9.7   5.3 |   5.8  42.4  360   9  5   7.5   4.1
  8500   4.3  39.7  350   8  4   9.3   5.1 |   6.2  43.2  360   8  4   7.0   3.9
  8250   4.9  40.8  350   8  4   8.3   4.6 |   6.6  43.9  360   7  3   6.1   3.3
  8000   5.5  41.9  350   8  4   8.8   4.8 |   7.0  44.6  355   6  3   6.5   3.6
  7750   6.2  43.2  345   8  4  10.3   5.6 |   7.4  45.3  345   5  3   7.7   4.2
  7500   7.0  44.6  345   8  4  10.2   5.6 |   8.0  46.4  340   5  2   9.1   5.0
  7250   7.7  45.9  345   8  4   9.4   5.1 |   8.6  47.5  335   5  2   9.4   5.2
  7000   8.4  47.1  345   8  4   9.6   5.3 |   9.3  48.7  330   4  2   9.3   5.1
  6750   9.1  48.4  340   8  4  10.0   5.5 |  10.0  50.0  325   4  2   9.7   5.3
  6500   9.9  49.8  340   7  4  10.2   5.6 |  10.7  51.3  325   4  2  10.1   5.5
  6250  10.6  51.1  340   7  4   9.8   5.4 |  11.5  52.7  320   4  2   9.8   5.4
  6000  11.4  52.5  340   7  4  10.6   5.8 |  12.2  54.0  315   4  2  10.5   5.7
  5750  12.3  54.1  340   7  4  15.0   8.2 |  13.0  55.4  315   4  2  11.5   6.3
  5500  13.5  56.3  335   7  3  19.9  10.9 |  13.8  56.8  310   4  2  11.5   6.3
________________________________________________________________________________

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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