Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 121229
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0629 MDT Sunday, April 12, 2015

This forecast is for Sunday, April 12, 2015:

If the trigger temperature of 64.0 F/17.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 873 ft/min (4.4 m/s)
   Maximum height of thermals.................. 14926 ft MSL (9641 ft AGL)

Forecast maximum temperature................... 69.0 F/21.0 C
Time of trigger temperature.................... 1130 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................. 6737 ft MSL (1451 ft AGL)
Thermal soaring outlook for Monday 04/13....... 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)................ Weak NVA
Potential height of wave....................... 15370 ft MSL (10085 ft AGL)
Wave soaring outlook for Monday 04/13.......... Poor

Remarks...

Sunrise/Sunset.................... 06:26:47 / 19:33:29 MDT
Total possible sunshine........... 13 hr 6 min 43 sec (786 min 43 sec)
Altitude of sun at 13:00:17 MDT... 59.01 degrees

Upper air data from rawinsonde observation taken on 04/12/2015 at 0600 MDT

Freezing level.................. 11404 ft MSL (6119 ft AGL)
Convective condensation level... 18914 ft MSL (13629 ft AGL)
Lifted condensation level....... 18648 ft MSL (13362 ft AGL)
Lifted index.................... +3.4
K index......................... -6.6

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  -60.9 -77.6   255   18    9   3.8   2.1   98.2 208.8    44.4      M    M
 45000  -59.8 -75.6   275   27   14   0.8   0.5   74.2 165.5    32.9      M    M
 40000  -57.9 -72.2   255   42   21  -7.3  -4.0   54.3 129.7    22.2      M    M
 38000  -59.6 -75.3   270   31   16   3.1   1.7   43.0 109.3    15.1      M    M
 36000  -55.4 -67.7   250   32   16   8.2   4.5   40.6 105.1    13.9      M    M
 34000  -52.2 -62.0   245   30   16   8.3   4.6   36.8  98.3    11.6      M    M
 32000  -48.6 -55.5   260   24   12   6.7   3.7   33.6  92.6     9.6      M    M
 30000  -43.4 -46.1   250   20   10   8.7   4.8   31.8  89.3     8.5      M    M
 29000  -40.8 -41.4   250   19   10   8.8   4.8   31.4  88.6     8.3      M    M
 28000  -38.1 -36.6   250   19   10   9.2   5.1   31.0  87.9     8.1      M    M
 27000  -35.4 -31.7   250   19   10   9.2   5.1   30.8  87.4     8.0      M    M
 26000  -32.6 -26.7   250   19   10   9.2   5.1   30.6  87.0     7.9      M    M
 25000  -29.8 -21.6   250   19   10   8.2   4.5   30.5  86.9     8.0      M    M
 24000  -28.1 -18.6   265   25   13   4.8   2.6   29.0  84.3     6.9      M    M
 23000  -26.8 -16.2   265   34   17   7.4   4.1   27.1  80.8     5.3      M    M
 22000  -24.7 -12.5   265   31   16   4.1   2.3   26.1  79.0     4.6      M    M
 21000  -23.2  -9.8   270   28   14   8.5   4.7   24.3  75.8     3.2      M    M
 20000  -21.1  -6.0   270   25   13   2.4   1.3   23.4  74.1     2.4      M    M
 19500  -20.6  -5.1   260   21   11   2.6   1.4   22.2  72.0     1.4      M    M
 19000  -19.8  -3.6   245   16    8   9.9   5.4   21.5  70.8     0.8      M    M
 18500  -18.2  -0.8   250   17    9  10.1   5.6   21.7  71.0     0.9      M    M
 18000  -16.7   1.9   260   16    8   9.9   5.4   21.6  70.9     0.9      M    M
 17500  -15.2   4.6   270   16    8   9.8   5.4   21.6  70.9     0.9      M    M
 17000  -13.8   7.2   285   16    8   9.8   5.4   21.6  71.0     0.9      M    M
 16500  -12.3   9.9   295   17    9   9.8   5.4   21.7  71.0     0.9      M    M
 16000  -10.8  12.6   305   19   10   9.8   5.4   21.7  71.1     1.0      M    M
 15500   -9.4  15.1   300   20   10   7.0   3.8   21.7  71.0     0.9      M    M
 15000   -8.2  17.2   290   21   11   5.4   2.9   20.6  69.1    -0.1    869  4.4
 14500   -7.4  18.7   295   19   10   5.3   2.9   19.9  67.8    -0.7    831  4.2
 14000   -6.4  20.5   295   18    9   8.8   4.8   19.4  67.0    -1.2    785  4.0
 13500   -5.2  22.6   300   21   11   8.4   4.6   19.2  66.5    -1.4    732  3.7
 13000   -3.9  25.0   300   23   12   8.4   4.6   19.0  66.1    -1.6    680  3.5
 12500   -2.7  27.1   305   26   14   8.5   4.6   18.8  65.8    -1.9    628  3.2
 12000   -1.4  29.5   305   29   15   8.6   4.7   18.6  65.4    -2.0    576  2.9
 11500   -0.1  31.8   295   26   13   8.9   4.9   18.4  65.2    -2.2    521  2.6
 11000    1.3  34.3   290   24   12   8.9   4.9   18.3  64.9    -2.4    466  2.4
 10500    2.6  36.7   280   22   11   9.0   4.9   18.2  64.7    -2.5    412  2.1
 10250    3.2  37.8   275   21   11   8.9   4.9   18.1  64.6    -2.6    384  2.0
 10000    3.9  39.0   270   19   10   9.2   5.0   18.1  64.5    -2.6    357  1.8
  9750    4.6  40.3   270   19   10   9.6   5.3   18.0  64.5    -2.6    328  1.7
  9500    5.3  41.5   265   19   10   9.5   5.2   18.0  64.5    -2.7    300  1.5
  9250    6.0  42.8   265   20   10   9.6   5.2   18.0  64.5    -2.7    271  1.4
  9000    6.8  44.2   265   21   11   9.6   5.2   18.0  64.5    -2.7    242  1.2
  8750    7.5  45.5   260   20   11   9.6   5.2   18.0  64.4    -2.7    214  1.1
  8500    8.2  46.8   260   20   10   9.6   5.2   18.0  64.4    -2.7    185  0.9
  8250    8.9  48.0   260   19   10   9.6   5.2   18.0  64.4    -2.8    156  0.8
  8000    9.6  49.3   255   19   10   9.6   5.2   18.0  64.4    -2.8    127  0.6
  7750   10.3  50.5   250   21   11   9.5   5.2   18.0  64.3    -2.8     99  0.5
  7500   11.0  51.8   245   22   11   9.7   5.3   17.9  64.3    -2.8     70  0.4
  7250   11.7  53.1   240   24   12   9.2   5.1   17.9  64.3    -2.9     41  0.2
  7000   12.4  54.3   235   26   13  10.8   5.9   17.9  64.3    -2.9     13  0.1
  6750   13.2  55.8   235   25   13   4.8   2.6   17.9  64.2    -2.9      M    M
  6500   13.2  55.8   235   24   12   0.8   0.5   17.2  63.0    -3.6      M    M
  6250   13.2  55.8   235   23   12  -5.6  -3.1   16.5  61.7    -4.4      M    M
  6000   11.9  53.4   235   22   11 -28.0 -15.4   14.5  58.1    -6.4      M    M
  5750    9.6  49.3   240   15    8 -25.7 -14.1   11.4  52.5    -9.5     62  0.3
  5500    8.6  47.5   250    7    4   1.1   0.6    9.8  49.6   -11.2     82  0.4

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

           04/12/2015 at 0900 MDT          |       04/12/2015 at 1200 MDT
                                           |
K index... +3.2  LI... +274.9              | K index... +11.6  LI... +274.2
CAPE... 0.0  CIN... -0.7                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -58.4 -73.1  260  17  9   0.5   0.3 | -57.8 -72.0  250  18  9   0.3   0.1
 45000 -57.6 -71.7  255  16  8  -0.1  -0.1 | -57.4 -71.3  260  26 13  -0.1  -0.0
 40000 -58.4 -73.1  240  26 13  -0.5  -0.3 | -57.9 -72.2  250  31 16  -0.3  -0.2
 38000 -57.2 -71.0  245  30 15   4.5   2.5 | -56.7 -70.1  245  35 18   4.5   2.5
 36000 -54.5 -66.1  245  34 17   4.5   2.5 | -54.0 -65.2  245  42 22   4.5   2.5
 34000 -51.7 -61.1  245  37 19   6.8   3.7 | -51.3 -60.3  245  48 25   5.7   3.1
 32000 -47.8 -54.0  245  36 19   6.5   3.6 | -47.5 -53.5  240  50 26   5.6   3.1
 30000 -43.2 -45.8  245  35 18   7.5   4.1 | -43.8 -46.8  240  51 26   7.5   4.1
 29000 -41.0 -41.8  245  35 18   7.5   4.1 | -41.6 -42.9  235  50 26   7.6   4.2
 28000 -38.7 -37.7  245  34 18   7.5   4.1 | -39.3 -38.7  235  49 25   7.6   4.2
 27000 -36.5 -33.7  240  34 17   7.6   4.2 | -37.0 -34.6  235  48 25   7.8   4.3
 26000 -34.2 -29.6  245  33 17   7.7   4.2 | -34.6 -30.3  235  46 24   8.0   4.4
 25000 -31.9 -25.4  245  32 16   7.7   4.3 | -32.2 -26.0  235  44 23   8.0   4.4
 24000 -29.5 -21.1  245  31 16   7.7   4.2 | -29.8 -21.6  235  42 22   7.7   4.2
 23000 -27.3 -17.1  245  30 16   7.6   4.2 | -28.1 -18.6  240  38 20   5.4   3.0
 22000 -25.0 -13.0  245  29 15   7.6   4.2 | -26.5 -15.7  240  34 18   5.4   3.0
 21000 -22.7  -8.9  245  28 14   6.1   3.3 | -24.8 -12.6  240  31 16   6.3   3.4
 20000 -21.3  -6.3  245  24 12   5.0   2.7 | -22.8  -9.0  235  28 14   6.9   3.8
 19500 -20.5  -4.9  240  22 11   5.0   2.7 | -21.7  -7.1  235  26 14   6.9   3.8
 19000 -19.8  -3.6  240  20 10   5.1   2.8 | -20.7  -5.3  230  25 13   7.0   3.8
 18500 -19.0  -2.2  240  18  9   5.9   3.2 | -19.7  -3.5  225  24 12   7.4   4.1
 18000 -18.0  -0.4  235  17  9   7.6   4.2 | -18.4  -1.1  225  22 11   8.3   4.6
 17500 -16.8   1.8  235  16  8   7.5   4.1 | -17.2   1.0  225  20 10   8.3   4.6
 17000 -15.6   3.9  235  14  7   9.5   5.2 | -15.3   4.5  225  18  9   8.7   4.8
 16500 -14.2   6.4  235  13  7   9.4   5.2 | -14.0   6.8  230  17  9   8.8   4.8
 16000 -12.0  10.4  250  12  6   9.7   5.3 | -12.7   9.1  235  17  9   9.2   5.1
 15500 -10.6  12.9  260  13  7   9.7   5.3 | -11.3  11.7  245  18  9   9.2   5.0
 15000  -9.2  15.4  270  14  7   9.0   4.9 |  -9.9  14.2  255  19 10   9.3   5.1
 14500  -7.9  17.8  275  16  8   8.9   4.9 |  -8.5  16.7  265  21 11   9.3   5.1
 14000  -6.5  20.3  280  18  9   8.8   4.8 |  -7.2  19.0  270  23 12   8.2   4.5
 13500  -5.3  22.5  285  20 10   8.7   4.8 |  -6.0  21.2  275  25 13   7.8   4.3
 13000  -4.0  24.8  285  22 11   8.4   4.6 |  -4.9  23.2  280  27 14   7.8   4.3
 12500  -2.8  27.0  285  23 12   8.0   4.4 |  -3.7  25.3  280  27 14   7.9   4.3
 12000  -1.6  29.1  290  23 12   8.1   4.4 |  -2.5  27.5  285  28 14   7.2   4.0
 11500  -0.4  31.3  290  23 12   8.2   4.5 |  -1.6  29.1  285  27 14   6.4   3.5
 11000   0.8  33.4  295  22 11   7.9   4.3 |  -0.7  30.7  290  27 14   5.9   3.2
 10500   1.9  35.4  295  22 11   7.1   3.9 |   0.1  32.2  295  25 13   4.8   2.6
 10250   2.5  36.5  300  22 11   9.2   5.1 |   0.5  32.9  295  24 12   7.5   4.1
 10000   3.3  37.9  300  22 11   9.7   5.3 |   1.2  34.2  300  22 11   8.5   4.7
  9750   3.9  39.0  300  23 12   7.5   4.1 |   1.7  35.1  305  20 10   6.5   3.6
  9500   4.4  39.9  300  24 12   7.5   4.1 |   2.2  36.0  310  18  9   7.2   4.0
  9250   5.0  41.0  300  25 13   7.7   4.2 |   2.7  36.9  315  16  8   6.5   3.6
  9000   5.6  42.1  305  26 13   7.1   3.9 |   3.2  37.8  320  14  7   8.0   4.4
  8750   6.1  43.0  300  26 14   6.5   3.6 |   3.9  39.0  320  14  7  10.1   5.6
  8500   6.6  43.9  300  27 14   6.4   3.5 |   4.6  40.3  320  14  7   9.8   5.4
  8250   7.0  44.6  300  28 14   7.0   3.8 |   5.4  41.7  325  14  7  10.4   5.7
  8000   7.6  45.7  300  28 14   8.4   4.6 |   6.2  43.2  325  13  7  10.8   5.9
  7750   8.2  46.8  300  27 14   7.8   4.3 |   6.9  44.4  325  13  7   9.7   5.3
  7500   8.8  47.8  300  26 13   6.7   3.7 |   7.6  45.7  325  13  7   8.9   4.9
  7250   9.3  48.7  305  24 13   7.7   4.2 |   8.3  46.9  325  13  7  10.0   5.5
  7000   9.9  49.8  305  23 12   8.6   4.7 |   9.1  48.4  325  13  7  11.0   6.0
  6750  10.5  50.9  305  21 11   7.2   3.9 |   9.9  49.8  325  13  7  10.1   5.6
  6500  10.9  51.6  305  19 10   6.0   3.3 |  10.6  51.1  325  13  7  10.0   5.5
  6250  11.3  52.3  305  17  9   2.2   1.2 |  11.4  52.5  325  13  7  10.7   5.9
  6000  11.2  52.2  310  14  7  -0.1  -0.0 |  12.2  54.0  325  13  6  11.0   6.1
  5750  11.2  52.2  305  11  6  -1.8  -1.0 |  13.1  55.6  325  12  6  10.3   5.6
  5500  10.8  51.4  300   6  3  -3.1  -1.7 |  13.9  57.0  325  12  6  15.2   8.4

           04/12/2015 at 1500 MDT          |       04/12/2015 at 1800 MDT
                                           |
K index... +4.6  LI... +273.2              | K index... +5.7  LI... +275.0
CAPE... 0.0  CIN... -30.4                  | 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  255  22 12   1.0   0.5 | -57.9 -72.2  255  20 10   1.1   0.6
 45000 -57.0 -70.6  255  26 13   1.0   0.5 | -56.4 -69.5  250  24 13   0.7   0.4
 40000 -55.6 -68.1  255  40 21   1.0   0.5 | -55.7 -68.3  255  45 23   0.4   0.2
 38000 -54.6 -66.3  255  48 25   2.2   1.2 | -54.8 -66.6  255  51 26   2.7   1.5
 36000 -53.3 -63.9  250  58 30   2.2   1.2 | -53.2 -63.8  250  56 29   2.7   1.5
 34000 -51.8 -61.2  245  67 35   5.4   3.0 | -51.0 -59.8  250  58 30   4.8   2.6
 32000 -48.1 -54.6  245  67 35   5.6   3.0 | -48.2 -54.8  255  49 25   4.8   2.6
 30000 -44.4 -47.9  240  66 34   7.9   4.3 | -45.0 -49.0  260  42 21   7.0   3.8
 29000 -42.0 -43.6  240  64 33   7.9   4.4 | -42.9 -45.2  265  39 20   7.0   3.9
 28000 -39.7 -39.5  240  62 32   7.9   4.4 | -40.8 -41.4  270  36 18   7.0   3.9
 27000 -37.3 -35.1  240  59 31   7.4   4.1 | -38.7 -37.7  275  33 17   7.3   4.0
 26000 -35.3 -31.5  245  54 28   6.7   3.7 | -36.4 -33.5  280  32 16   7.6   4.2
 25000 -33.2 -27.8  245  49 25   6.7   3.7 | -34.1 -29.4  285  30 16   7.6   4.2
 24000 -31.2 -24.2  250  43 22   6.7   3.7 | -31.8 -25.2  290  29 15   7.6   4.1
 23000 -29.3 -20.7  250  39 20   6.5   3.6 | -29.6 -21.3  290  28 14   7.3   4.0
 22000 -27.3 -17.1  255  35 18   6.5   3.6 | -27.4 -17.3  290  27 14   7.3   4.0
 21000 -25.4 -13.7  255  31 16   7.1   3.9 | -25.2 -13.4  285  26 13   7.9   4.3
 20000 -23.1  -9.6  260  29 15   7.5   4.1 | -22.8  -9.0  280  27 14   8.1   4.5
 19500 -22.0  -7.6  260  28 14   7.5   4.1 | -21.6  -6.9  280  27 14   8.1   4.5
 19000 -20.9  -5.6  260  27 14   7.5   4.1 | -20.3  -4.5  275  28 14   8.1   4.5
 18500 -19.8  -3.6  265  26 13   8.1   4.4 | -19.1  -2.4  275  29 15   7.9   4.3
 18000 -18.4  -1.1  270  26 14   8.8   4.8 | -18.0  -0.4  275  30 16   7.6   4.2
 17500 -17.1   1.2  275  27 14   9.0   4.9 | -16.3   2.7  275  32 17   8.1   4.4
 17000 -15.4   4.3  280  29 15   7.3   4.0 | -15.1   4.8  275  31 16   8.4   4.6
 16500 -14.3   6.3  280  30 15   7.4   4.0 | -13.8   7.2  280  30 16   8.4   4.6
 16000 -13.1   8.4  280  30 16   8.7   4.8 | -12.6   9.3  280  30 16   8.4   4.6
 15500 -11.8  10.8  280  31 16   8.7   4.8 | -11.3  11.7  280  31 16   8.4   4.6
 15000 -10.6  12.9  285  32 17   8.1   4.5 | -10.1  13.8  280  31 16   8.3   4.6
 14500  -9.3  15.3  285  33 17   8.1   4.5 |  -8.9  16.0  285  30 16   8.3   4.6
 14000  -8.1  17.4  285  33 17   8.0   4.4 |  -7.6  18.3  285  30 16   8.6   4.7
 13500  -7.0  19.4  285  33 17   8.0   4.4 |  -6.3  20.7  285  30 16   8.7   4.8
 13000  -5.8  21.6  290  33 17   8.2   4.5 |  -5.0  23.0  290  30 16   8.7   4.8
 12500  -4.6  23.7  290  32 16   8.3   4.6 |  -3.7  25.3  290  30 16   8.7   4.8
 12000  -3.4  25.9  290  31 16   8.6   4.7 |  -2.4  27.7  295  30 15   8.3   4.6
 11500  -2.1  28.2  290  27 14   8.8   4.8 |  -1.2  29.8  300  29 15   8.2   4.5
 11000  -0.8  30.6  290  24 12   8.2   4.5 |  -0.0  32.0  300  28 14   7.4   4.1
 10500   0.3  32.5  295  22 11   7.1   3.9 |   1.0  33.8  305  26 13   6.4   3.5
 10250   0.9  33.6  295  20 10  10.8   5.9 |   1.6  34.9  305  25 13   9.9   5.5
 10000   1.8  35.2  295  19 10  12.0   6.6 |   2.4  36.3  310  24 12  10.8   5.9
  9750   2.6  36.7  295  19 10   9.1   5.0 |   3.1  37.6  310  22 12   7.8   4.3
  9500   3.3  37.9  300  19 10  10.1   5.6 |   3.7  38.7  315  21 11   8.6   4.7
  9250   4.0  39.2  300  18  9   9.0   4.9 |   4.3  39.7  315  20 10   8.4   4.6
  9000   4.7  40.5  300  18  9   9.2   5.0 |   5.0  41.0  320  19 10   9.2   5.1
  8750   5.4  41.7  300  18  9  10.4   5.7 |   5.7  42.3  320  19 10   9.9   5.5
  8500   6.2  43.2  300  18  9  10.2   5.6 |   6.4  43.5  325  18  9   9.8   5.4
  8250   7.0  44.6  300  17  9  10.4   5.7 |   7.1  44.8  325  17  9  10.0   5.5
  8000   7.7  45.9  300  17  9  10.3   5.7 |   7.9  46.2  325  17  9  10.0   5.5
  7750   8.5  47.3  300  17  9   9.8   5.4 |   8.6  47.5  330  17  9   9.7   5.3
  7500   9.2  48.6  300  17  9   9.6   5.3 |   9.3  48.7  330  17  9   9.5   5.2
  7250   9.9  49.8  300  17  9  10.3   5.7 |  10.1  50.2  330  16  8   9.7   5.3
  7000  10.7  51.3  305  17  9  10.8   5.9 |  10.8  51.4  330  16  8   9.8   5.4
  6750  11.5  52.7  305  16  8   9.3   5.1 |  11.5  52.7  330  16  8   9.3   5.1
  6500  12.2  54.0  305  16  8   9.5   5.2 |  12.2  54.0  330  16  8   9.8   5.4
  6250  13.0  55.4  305  16  8  11.4   6.3 |  13.0  55.4  330  16  8  10.9   6.0
  6000  13.8  56.8  305  15  8  11.6   6.4 |  13.8  56.8  335  15  8  10.9   6.0
  5750  14.7  58.5  305  15  8  11.0   6.1 |  14.6  58.3  335  15  7  10.7   5.9
  5500  15.6  60.1  305  14  7  16.3   8.9 |  15.4  59.7  335  14  7  11.8   6.5
________________________________________________________________________________

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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