Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 280019
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1819 MDT Friday, March 27, 2015

This forecast is for Saturday, March 28, 2015:

If the trigger temperature of 66.5 F/19.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1315 ft/min (6.7 m/s)
   Maximum height of thermals.................. 19584 ft MSL (14277 ft AGL)

Forecast maximum temperature................... 79.0 F/26.6 C
Time of trigger temperature.................... 1100 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................. 16874 ft MSL (11567 ft AGL)
Thermal soaring outlook for Sunday 03/29....... 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....................... 18091 ft MSL (12784 ft AGL)
Wave soaring outlook for Sunday 03/29.......... Poor

Remarks...

Sunrise/Sunset.................... 06:50:19 / 19:18:24 MDT
Total possible sunshine........... 12 hr 28 min 6 sec (748 min 6 sec)
Altitude of sun at 13:04:31 MDT... 53.33 degrees

Upper air data from numerical model forecast valid on 03/28/2015 at 0600 MDT

Freezing level.................. 12138 ft MSL (6831 ft AGL)
Convective condensation level... 14330 ft MSL (9023 ft AGL)
Lifted condensation level....... 16441 ft MSL (11134 ft AGL)
Lifted index.................... -3.3
K index......................... +9.6

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  -60.8 -77.4   330   29   15   3.9   2.1      M     M       M      M    M
 45000  -54.4 -65.9   335   41   21   4.9   2.7      M     M       M      M    M
 40000  -47.1 -52.8   335   53   27   5.2   2.9      M     M       M      M    M
 38000  -46.6 -51.9   335   54   28  -0.0  -0.0      M     M       M      M    M
 36000  -46.6 -51.9   335   54   28  -0.0  -0.0      M     M       M      M    M
 34000  -46.2 -51.2   335   54   28   2.0   1.1      M     M       M      M    M
 32000  -45.0 -49.0   330   53   27   2.0   1.1      M     M       M      M    M
 30000  -42.1 -43.8   330   52   27   7.7   4.2   32.9  91.1     5.1      M    M
 29000  -39.8 -39.6   330   52   27   7.7   4.2   32.0  89.6     4.5      M    M
 28000  -37.5 -35.5   330   52   27   7.7   4.2   31.3  88.3     4.0      M    M
 27000  -35.1 -31.2   330   51   26   9.1   5.0   30.7  87.3     3.6      M    M
 26000  -32.3 -26.1   330   51   26   9.1   5.0   30.4  86.8     3.4      M    M
 25000  -29.6 -21.3   330   50   26   9.1   5.0   30.2  86.4     3.3      M    M
 24000  -26.9 -16.4   330   48   25   8.1   4.5   30.0  85.9     3.1      M    M
 23000  -24.5 -12.1   325   41   21   8.2   4.5   29.3  84.8     2.6      M    M
 22000  -22.0  -7.6   320   34   17   8.2   4.5   28.8  83.9     2.2      M    M
 21000  -19.8  -3.6   320   29   15   6.2   3.4   28.0  82.4     1.6      M    M
 20000  -17.9  -0.2   320   28   14   6.3   3.4   26.7  80.1     0.5      M    M
 19500  -17.0   1.4   320   27   14   6.3   3.5   26.1  79.0    -0.0   1314  6.7
 19000  -16.1   3.0   325   26   13   6.3   3.5   25.6  78.0    -0.5   1271  6.5
 18500  -15.2   4.6   325   26   14   5.8   3.2   25.0  76.9    -1.1   1229  6.2
 18000  -14.3   6.3   325   27   14   5.9   3.2   24.3  75.7    -1.7   1189  6.0
 17500  -13.4   7.9   325   28   14   6.4   3.5   23.7  74.6    -2.3   1147  5.8
 17000  -12.4   9.7   325   27   14   6.7   3.7   23.1  73.6    -2.8   1103  5.6
 16500  -11.5  11.3   325   26   13   6.9   3.8   22.6  72.7    -3.3   1059  5.4
 16000   -9.8  14.4   325   24   13   7.7   4.2   22.0  71.7    -3.8    987  5.0
 15500   -8.7  16.3   325   24   12   8.0   4.4   21.7  71.1    -4.2    938  4.8
 15000   -7.4  18.7   325   23   12   8.3   4.6   21.5  70.6    -4.4    887  4.5
 14500   -6.2  20.8   325   22   11   8.5   4.7   21.2  70.2    -4.7    835  4.2
 14000   -4.9  23.2   330   21   11   9.3   5.1   21.1  70.0    -4.8    780  4.0
 13500   -3.5  25.7   330   21   11   9.2   5.1   21.0  69.8    -4.9    724  3.7
 13000   -2.1  28.2   330   21   11   8.9   4.9   20.9  69.6    -5.1    669  3.4
 12500   -0.8  30.6   330   21   11   8.9   4.9   20.8  69.4    -5.2    614  3.1
 12000    0.5  32.9   330   21   11   9.5   5.2   20.7  69.2    -5.4    559  2.8
 11500    2.4  36.3   330   21   11   9.6   5.3   20.6  69.2    -5.5    502  2.5
 11000    3.3  37.9   330   20   10   8.4   4.6   20.5  68.9    -5.6    448  2.3
 10500    4.5  40.1   330   20   10   8.9   4.9   20.3  68.6    -5.9    396  2.0
 10250    5.1  41.2   330   20   10   4.6   2.5   20.2  68.3    -6.1    372  1.9
 10000    5.3  41.5   325   19   10   6.3   3.5   19.7  67.4    -6.6    357  1.8
  9750    6.0  42.8   325   19   10  11.2   6.1   19.7  67.4    -6.6    328  1.7
  9500    6.7  44.1   325   18    9  10.0   5.5   19.7  67.5    -6.6    299  1.5
  9250    7.4  45.3   325   18    9   7.3   4.0   19.7  67.4    -6.7    272  1.4
  9000    7.9  46.2   325   18    9   7.7   4.2   19.4  67.0    -7.0    251  1.3
  8750    8.6  47.5   325   18    9  10.8   5.9   19.4  67.0    -7.0    222  1.1
  8500    9.3  48.7   320   18    9   9.7   5.3   19.5  67.1    -7.0    193  1.0
  8250   10.0  50.0   320   18    9   8.4   4.6   19.4  67.0    -7.1    166  0.8
  8000   10.5  50.9   320   19   10   7.9   4.3   19.3  66.7    -7.3    142  0.7
  7750   11.1  52.0   315   20   10   8.4   4.6   19.2  66.5    -7.5    117  0.6
  7500   11.7  53.1   315   21   11   7.6   4.2   19.1  66.3    -7.7     92  0.5
  7250   12.2  54.0   310   22   11   6.5   3.6   18.8  65.9    -7.9     70  0.4
  7000   12.6  54.7   305   23   12   6.9   3.8   18.6  65.5    -8.2     48  0.2
  6750   13.1  55.6   300   24   12   5.5   3.0   18.4  65.1    -8.5     27  0.1
  6500   13.3  55.9   300   23   12  -2.9  -1.6   17.8  64.0    -9.1     15  0.1
  6250   12.7  54.9   295   21   11  -9.4  -5.1   16.5  61.7   -10.4     23  0.1
  6000   12.2  54.0   290   19   10  -2.9  -1.6   15.2  59.4   -11.7     32  0.2
  5750   11.8  53.2   280   17    9 -14.6  -8.0   14.1  57.5   -12.8     35  0.2
  5500    9.2  48.6   270   12    6 -54.9 -30.1   10.9  51.5   -16.1    106  0.5

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

           03/28/2015 at 0900 MDT          |       03/28/2015 at 1200 MDT
                                           |
K index... +8.2  LI... +275.5              | K index... +0.4  LI... +274.3
CAPE... 0.0  CIN... -0.6                   | CAPE... 0.0  CIN... -0.6
                                           |
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 -61.2 -78.2  325  28 14   3.7   2.0 | -61.2 -78.2  315  26 13   3.1   1.7
 45000 -55.1 -67.2  330  39 20   4.9   2.7 | -55.7 -68.3  325  37 19   5.4   2.9
 40000 -47.7 -53.9  330  48 25   5.3   2.9 | -47.6 -53.7  320  48 25   5.8   3.2
 38000 -46.5 -51.7  330  50 26   1.5   0.8 | -46.1 -51.0  315  49 25   2.1   1.1
 36000 -45.6 -50.1  325  51 26   1.5   0.8 | -44.9 -48.8  315  50 26   2.1   1.1
 34000 -44.9 -48.8  325  52 27   0.9   0.5 | -44.1 -47.4  315  50 26  -0.2  -0.1
 32000 -44.3 -47.7  325  50 26   0.9   0.5 | -44.3 -47.7  310  49 25  -0.2  -0.1
 30000 -41.8 -43.2  325  49 25   7.9   4.3 | -41.9 -43.4  310  47 24   8.4   4.6
 29000 -39.4 -38.9  325  48 24   7.9   4.3 | -39.4 -38.9  315  45 23   8.4   4.6
 28000 -37.1 -34.8  325  46 24   7.9   4.3 | -36.9 -34.4  315  43 22   8.4   4.6
 27000 -34.7 -30.5  325  45 23   8.2   4.5 | -34.3 -29.7  315  41 21   8.4   4.6
 26000 -32.2 -26.0  325  45 23   8.2   4.5 | -31.8 -25.2  310  39 20   8.4   4.6
 25000 -29.8 -21.6  325  44 22   8.2   4.5 | -29.3 -20.7  310  37 19   8.4   4.6
 24000 -27.2 -17.0  325  41 21   9.0   4.9 | -26.8 -16.2  305  34 17   8.4   4.6
 23000 -24.6 -12.3  325  36 19   8.9   4.9 | -24.3 -11.7  300  29 15   8.4   4.6
 22000 -21.9  -7.4  330  31 16   8.9   4.9 | -21.7  -7.1  295  24 12   8.4   4.6
 21000 -19.4  -2.9  330  28 14   7.4   4.1 | -19.3  -2.7  295  22 11   7.6   4.2
 20000 -17.2   1.0  325  27 14   7.4   4.1 | -17.0   1.4  295  22 11   7.6   4.2
 19500 -16.1   3.0  325  27 14   7.4   4.1 | -15.9   3.4  295  22 11   7.6   4.2
 19000 -15.0   5.0  325  27 14   7.5   4.1 | -14.8   5.4  300  22 11   7.6   4.2
 18500 -14.0   6.8  325  26 13   5.2   2.9 | -13.7   7.3  300  21 11   6.2   3.4
 18000 -13.2   8.2  325  25 13   5.4   3.0 | -12.8   9.0  295  20 11   6.3   3.4
 17500 -12.4   9.7  325  24 12   5.5   3.0 | -11.9  10.6  295  20 10   6.4   3.5
 17000 -11.6  11.1  320  23 12   5.5   3.0 | -10.9  12.4  295  18  9   6.4   3.5
 16500 -10.4  13.3  320  21 11   6.6   3.6 |  -9.5  14.9  295  16  8   6.4   3.5
 16000  -9.4  15.1  320  19 10   6.9   3.8 |  -8.6  16.5  295  15  8   6.4   3.5
 15500  -8.4  16.9  320  17  9   7.4   4.0 |  -7.6  18.3  295  13  7   6.9   3.8
 15000  -7.2  19.0  325  16  8   7.9   4.3 |  -6.6  20.1  295  12  6   7.4   4.1
 14500  -6.0  21.2  325  15  8   8.1   4.4 |  -5.5  22.1  290  11  6   7.7   4.2
 14000  -4.8  23.4  325  15  8   8.7   4.8 |  -4.2  24.4  295  10  5   8.7   4.8
 13500  -3.5  25.7  330  15  8   8.7   4.8 |  -2.9  26.8  295   9  5   8.7   4.8
 13000  -2.2  28.0  330  15  8   9.1   5.0 |  -1.6  29.1  300   9  4   9.2   5.1
 12500  -0.8  30.6  325  15  8   9.0   5.0 |  -0.2  31.6  300   9  4   9.1   5.0
 12000   0.5  32.9  325  15  8   9.4   5.1 |   1.2  34.2  305   9  5   9.7   5.3
 11500   1.9  35.4  325  16  8   9.5   5.2 |   2.6  36.7  310  11  5   9.7   5.3
 11000   3.1  37.6  320  17  9   8.2   4.5 |   4.0  39.2  310  13  7   9.0   5.0
 10500   4.4  39.9  315  17  9   8.6   4.7 |   5.4  41.7  305  17  9   9.1   5.0
 10250   4.9  40.8  315  17  9   4.2   2.3 |   5.9  42.6  305  18  9   4.7   2.6
 10000   5.1  41.2  310  17  9   5.9   3.2 |   6.2  43.2  305  19 10   5.3   2.9
  9750   5.8  42.4  310  16  8  10.7   5.9 |   6.8  44.2  305  21 11   9.1   5.0
  9500   6.5  43.7  305  16  8   9.5   5.2 |   7.3  45.1  300  23 12   8.1   4.4
  9250   7.2  45.0  305  15  8   7.7   4.2 |   7.8  46.0  300  24 12   5.8   3.2
  9000   7.7  45.9  305  15  8   8.3   4.6 |   8.1  46.6  300  23 12   6.0   3.3
  8750   8.5  47.3  305  15  8  11.0   6.1 |   8.7  47.7  295  21 11   8.0   4.4
  8500   9.2  48.6  305  15  8   9.9   5.4 |   9.2  48.6  290  19 10   7.9   4.3
  8250   9.9  49.8  305  15  8   8.4   4.6 |   9.8  49.6  290  17  9   8.8   4.8
  8000  10.5  50.9  305  16  8   7.7   4.2 |  10.4  50.7  285  15  8   8.9   4.9
  7750  11.0  51.8  305  17  9   7.8   4.3 |  11.0  51.8  280  13  7   8.2   4.5
  7500  11.6  52.9  300  18  9   7.5   4.1 |  11.6  52.9  275  11  6   9.0   5.0
  7250  12.1  53.8  300  19 10   7.1   3.9 |  12.3  54.1  275  11  5  10.1   5.5
  7000  12.6  54.7  295  20 10   7.5   4.1 |  13.1  55.6  270  10  5   9.9   5.4
  6750  13.1  55.6  295  21 11   5.0   2.8 |  13.8  56.8  270   9  5  10.0   5.5
  6500  13.3  55.9  290  21 11  -2.1  -1.2 |  14.5  58.1  270   9  5  10.2   5.6
  6250  12.9  55.2  290  18  9  -5.9  -3.2 |  15.3  59.5  270   9  4  10.7   5.9
  6000  12.5  54.5  280  16  8  -3.1  -1.7 |  16.1  61.0  265   8  4   9.3   5.1
  5750  12.2  54.0  275  14  7  -6.9  -3.8 |  16.8  62.2  265   8  4  12.5   6.8
  5500  11.2  52.2  260  11  5 -19.8 -10.8 |  18.1  64.6  265   8  4  22.3  12.2

           03/28/2015 at 1500 MDT          |       03/28/2015 at 1800 MDT
                                           |
K index... +2.7  LI... +273.6              | K index... +9.7  LI... +274.3
CAPE... 0.0  CIN... -66.2                  | CAPE... +0.9  CIN... -84.0
                                           |
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 -61.2 -78.2  295  25 13   2.8   1.5 | -60.7 -77.3  285  29 15   2.8   1.6
 45000 -55.9 -68.6  295  34 17   5.9   3.2 | -55.6 -68.1  295  39 20   5.4   3.0
 40000 -47.1 -52.8  305  44 23   6.4   3.5 | -47.5 -53.5  300  49 25   5.9   3.2
 38000 -45.8 -50.4  305  48 25   1.5   0.8 | -46.5 -51.7  295  52 27   1.1   0.6
 36000 -44.9 -48.8  300  53 27   1.5   0.8 | -45.8 -50.4  295  54 28   1.1   0.6
 34000 -44.4 -47.9  300  55 28  -0.1  -0.0 | -45.2 -49.4  290  56 29   0.9   0.5
 32000 -44.4 -47.9  300  55 28  -0.1  -0.0 | -44.6 -48.3  290  54 28   1.0   0.5
 30000 -42.0 -43.6  295  50 26   8.3   4.6 | -41.7 -43.1  290  52 27   8.7   4.8
 29000 -39.5 -39.1  295  45 23   8.4   4.6 | -39.1 -38.4  285  50 26   8.7   4.8
 28000 -37.0 -34.6  295  40 21   8.4   4.6 | -36.5 -33.7  285  48 25   8.7   4.8
 27000 -34.5 -30.1  295  37 19   8.2   4.5 | -34.0 -29.2  285  46 24   8.1   4.5
 26000 -32.1 -25.8  295  37 19   8.2   4.5 | -31.5 -24.7  290  43 22   8.1   4.4
 25000 -29.6 -21.3  295  36 19   8.2   4.5 | -29.1 -20.4  290  40 21   8.1   4.5
 24000 -27.2 -17.0  295  35 18   8.4   4.6 | -26.6 -15.9  290  38 19   8.8   4.9
 23000 -24.6 -12.3  295  33 17   8.4   4.6 | -24.0 -11.2  290  36 19   8.8   4.8
 22000 -22.1  -7.8  290  30 15   8.4   4.6 | -21.4  -6.5  295  35 18   8.8   4.8
 21000 -19.7  -3.5  290  28 14   7.9   4.3 | -18.8  -1.8  295  34 17   8.2   4.5
 20000 -17.3   0.9  290  25 13   7.9   4.3 | -16.4   2.5  295  32 16   8.2   4.5
 19500 -16.1   3.0  290  24 13   7.9   4.3 | -15.1   4.8  295  31 16   8.2   4.5
 19000 -15.0   5.0  295  23 12   7.9   4.3 | -13.9   7.0  295  30 15   8.2   4.5
 18500 -13.8   7.2  295  22 11   7.2   3.9 | -12.8   9.0  295  30 15   7.1   3.9
 18000 -12.8   9.0  295  21 11   7.2   3.9 | -11.7  10.9  300  31 16   7.2   3.9
 17500 -11.7  10.9  295  21 11   7.7   4.2 | -10.7  12.7  300  31 16   6.7   3.7
 17000 -10.5  13.1  300  20 10   7.9   4.3 |  -9.7  14.5  300  33 17   6.5   3.5
 16500  -9.3  15.3  300  19 10   8.1   4.4 |  -8.3  17.1  300  34 18   6.7   3.7
 16000  -7.4  18.7  300  20 10   8.5   4.6 |  -7.3  18.9  300  34 18   6.8   3.7
 15500  -6.2  20.8  305  20 10   8.3   4.5 |  -6.3  20.7  300  35 18   7.3   4.0
 15000  -5.0  23.0  305  20 10   8.1   4.4 |  -5.2  22.6  295  34 18   7.9   4.4
 14500  -3.8  25.2  305  21 11   8.0   4.4 |  -4.0  24.8  295  34 18   8.1   4.4
 14000  -2.6  27.3  305  22 11   7.7   4.2 |  -2.8  27.0  295  33 17   8.8   4.8
 13500  -1.5  29.3  305  23 12   7.7   4.2 |  -1.5  29.3  290  31 16   8.8   4.8
 13000  -0.4  31.3  300  24 12   7.1   3.9 |  -0.3  31.5  290  30 15   8.4   4.6
 12500   0.6  33.1  300  24 12   7.2   3.9 |   1.0  33.8  285  28 14   8.5   4.6
 12000   1.7  35.1  300  24 12   7.9   4.3 |   2.2  36.0  280  26 14   9.0   4.9
 11500   2.8  37.0  295  23 12   7.9   4.3 |   3.5  38.3  280  25 13   8.9   4.9
 11000   3.9  39.0  290  20 10   8.7   4.8 |   4.9  40.8  275  23 12   9.5   5.2
 10500   5.2  41.4  280  17  9   8.8   4.8 |   6.3  43.3  270  21 11  10.3   5.6
 10250   5.7  42.3  280  16  8   5.5   3.0 |   7.0  44.6  270  20 10   6.3   3.4
 10000   6.1  43.0  275  15  8   7.9   4.3 |   7.3  45.1  270  19 10   6.9   3.8
  9750   6.9  44.4  275  14  7  12.2   6.7 |   8.1  46.6  265  18  9  11.2   6.1
  9500   7.7  45.9  275  13  7  11.1   6.1 |   8.8  47.8  265  17  9  10.3   5.7
  9250   8.5  47.3  270  13  6   8.9   4.9 |   9.6  49.3  260  16  8   9.4   5.2
  9000   9.1  48.4  270  12  6   9.0   4.9 |  10.2  50.4  260  15  8   8.4   4.6
  8750   9.9  49.8  270  12  6  11.1   6.1 |  10.9  51.6  260  14  7   9.1   5.0
  8500  10.7  51.3  270  12  6  10.4   5.7 |  11.6  52.9  255  13  7   8.9   4.9
  8250  11.5  52.7  270  12  6  10.3   5.6 |  12.2  54.0  250  12  6   9.2   5.0
  8000  12.2  54.0  270  12  6  10.0   5.5 |  12.9  55.2  250  11  6   8.9   4.9
  7750  12.9  55.2  270  12  6   9.7   5.3 |  13.5  56.3  245  11  5   8.0   4.4
  7500  13.7  56.7  270  11  6   9.8   5.4 |  14.1  57.4  240  10  5   8.5   4.6
  7250  14.4  57.9  270  11  6   9.9   5.4 |  14.8  58.6  240  10  5   9.8   5.4
  7000  15.1  59.2  270  11  6   9.9   5.4 |  15.5  59.9  235   9  5  10.1   5.5
  6750  15.9  60.6  270  11  6  10.2   5.6 |  16.2  61.2  235   9  5   9.2   5.0
  6500  16.7  62.1  270  11  6  10.4   5.7 |  16.9  62.4  235   9  5   9.5   5.2
  6250  17.4  63.3  270  10  5  10.6   5.8 |  17.6  63.7  235   9  4  10.2   5.6
  6000  18.2  64.8  270  10  5   9.8   5.4 |  18.4  65.1  235   8  4  10.1   5.5
  5750  19.0  66.2  270  10  5  12.6   6.9 |  19.1  66.4  235   8  4   9.4   5.1
  5500  20.2  68.4  270   9  5  21.0  11.5 |  19.7  67.5  230   7  4   7.9   4.4
________________________________________________________________________________

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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