Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 220119
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1918 MDT Saturday, March 21, 2015

This forecast is for Sunday, March 22, 2015:

If the trigger temperature of 63.2 F/17.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1022 ft/min (5.2 m/s)
   Maximum height of thermals.................. 17972 ft MSL (12665 ft AGL)

Forecast maximum temperature................... 69.0 F/21.0 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10142 ft MSL (4835 ft AGL)
Thermal soaring outlook for Monday 03/23....... 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 PVA
Potential height of wave....................... 39102 ft MSL (33795 ft AGL)
Wave soaring outlook for Monday 03/23.......... Poor

Remarks... None

Sunrise/Sunset.................... 06:59:57 / 19:12:19 MDT
Total possible sunshine........... 12 hr 12 min 22 sec (732 min 22 sec)
Altitude of sun at 13:06:19 MDT... 50.97 degrees

Upper air data from numerical model forecast valid on 03/22/2015 at 0600 MDT

Freezing level.................. 11378 ft MSL (6071 ft AGL)
Convective condensation level... 17040 ft MSL (11733 ft AGL)
Lifted condensation level....... 17311 ft MSL (12004 ft AGL)
Lifted index.................... +0.8
K index......................... +8.7

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  -57.9 -72.2   255   40   20   2.2   1.2      M     M       M      M    M
 45000  -54.6 -66.3   260   43   22   0.0   0.0      M     M       M      M    M
 40000  -58.8 -73.8   290   45   23  -2.8  -1.6      M     M       M      M    M
 38000  -58.9 -74.0   300   47   24   3.2   1.8      M     M       M      M    M
 36000  -56.7 -70.1   305   49   25   3.2   1.8      M     M       M      M    M
 34000  -54.1 -65.4   310   49   25   7.7   4.2      M     M       M      M    M
 32000  -49.4 -56.9   315   45   23   7.8   4.3      M     M       M      M    M
 30000  -44.6 -48.3   320   42   22   8.4   4.6   30.9  87.5     7.7      M    M
 29000  -42.0 -43.6   320   42   22   8.4   4.6   30.2  86.4     7.4      M    M
 28000  -39.5 -39.1   320   42   22   8.4   4.6   29.8  85.6     7.1      M    M
 27000  -37.0 -34.6   320   42   22   7.5   4.1   29.3  84.8     6.8      M    M
 26000  -34.8 -30.6   320   38   20   7.2   4.0   28.2  82.8     6.0      M    M
 25000  -32.7 -26.9   315   34   18   7.2   4.0   27.3  81.1     5.4      M    M
 24000  -30.5 -22.9   310   31   16   7.3   4.0   26.5  79.7     4.8      M    M
 23000  -28.3 -18.9   305   28   15   7.5   4.1   25.5  77.9     4.0      M    M
 22000  -26.0 -14.8   300   26   14   7.5   4.1   24.7  76.5     3.4      M    M
 21000  -23.8 -10.8   295   24   13   6.7   3.7   23.9  75.1     2.7      M    M
 20000  -21.9  -7.4   300   23   12   6.7   3.7   22.8  73.0     1.7      M    M
 19500  -20.9  -5.6   305   22   12   6.7   3.7   22.2  72.0     1.3      M    M
 19000  -19.9  -3.8   305   22   11   6.7   3.7   21.7  71.1     0.8      M    M
 18500  -18.3  -0.9   310   21   11   7.8   4.3   21.1  69.9     0.3      M    M
 18000  -17.2   1.0   310   20   11   7.7   4.2   20.7  69.3    -0.1   1213  6.2
 17500  -16.0   3.2   315   20   10   8.6   4.7   20.4  68.8    -0.3   1163  5.9
 17000  -14.6   5.7   315   19   10   8.8   4.8   20.3  68.5    -0.5   1109  5.6
 16500  -13.3   8.1   315   19   10   8.8   4.8   20.1  68.2    -0.6   1054  5.4
 16000  -12.0  10.4   315   19   10   8.9   4.9   19.9  67.9    -0.8   1000  5.1
 15500  -10.7  12.7   315   18    9   8.9   4.9   19.8  67.6    -0.9    945  4.8
 15000   -9.3  15.3   315   18    9   8.9   4.9   19.7  67.4    -1.1    890  4.5
 14500   -8.0  17.6   310   17    9   8.9   4.9   19.5  67.1    -1.2    835  4.2
 14000   -6.7  19.9   310   16    8   8.6   4.7   19.4  66.8    -1.3    781  4.0
 13500   -5.4  22.3   315   16    8   8.6   4.7   19.2  66.5    -1.5    727  3.7
 13000   -4.1  24.6   315   15    8   8.9   4.9   19.0  66.2    -1.7    673  3.4
 12500   -2.8  27.0   315   15    8   8.9   4.9   18.9  66.0    -1.8    618  3.1
 12000   -1.5  29.3   315   14    7   8.2   4.5   18.7  65.7    -2.0    565  2.9
 11500   -0.2  31.6   315   14    7   8.1   4.4   18.4  65.2    -2.3    513  2.6
 11000    1.0  33.8   315   13    7   8.5   4.6   18.2  64.7    -2.5    462  2.3
 10500    2.3  36.1   315   12    6   9.3   5.1   18.0  64.3    -2.7    409  2.1
 10250    2.9  37.2   315   12    6   5.2   2.8   17.9  64.2    -2.8    382  1.9
 10000    3.2  37.8   315   12    6   6.6   3.6   17.4  63.3    -3.3    367  1.9
  9750    4.0  39.2   315   11    6  11.8   6.4   17.5  63.5    -3.2    335  1.7
  9500    4.8  40.6   315   11    6  10.8   5.9   17.6  63.6    -3.2    304  1.5
  9250    5.6  42.1   315   11    6   9.4   5.2   17.6  63.7    -3.1    272  1.4
  9000    6.2  43.2   320   11    6   8.5   4.7   17.5  63.5    -3.2    247  1.3
  8750    6.9  44.4   320   12    6   9.9   5.5   17.5  63.5    -3.3    218  1.1
  8500    7.6  45.7   320   12    6   9.8   5.4   17.5  63.5    -3.3    189  1.0
  8250    8.4  47.1   320   13    7  10.1   5.5   17.5  63.5    -3.3    159  0.8
  8000    9.1  48.4   320   14    7  10.0   5.5   17.6  63.6    -3.3    130  0.7
  7750    9.8  49.6   320   15    8   9.2   5.1   17.5  63.6    -3.3    101  0.5
  7500   10.5  50.9   320   16    8   8.6   4.7   17.5  63.5    -3.4     74  0.4
  7250   11.1  52.0   315   17    9   8.4   4.6   17.4  63.3    -3.5     48  0.2
  7000   11.7  53.1   315   18    9   7.6   4.2   17.3  63.1    -3.6     22  0.1
  6750   12.3  54.1   310   19   10   9.5   5.2   17.1  62.8    -3.8      M    M
  6500   12.8  55.0   310   20   10  -1.7  -0.9   16.9  62.4    -4.1      M    M
  6250   12.0  53.6   300   18    9 -13.0  -7.1   15.4  59.7    -5.6      M    M
  6000   11.2  52.2   295   17    9  -7.1  -3.9   13.9  57.0    -7.1      7  0.0
  5750   10.5  50.9   280   15    8 -17.5  -9.6   12.4  54.4    -8.6     22  0.1
  5500    7.7  45.9   265   11    6 -59.1 -32.4    9.0  48.2   -12.1     98  0.5

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

           03/22/2015 at 0900 MDT          |       03/22/2015 at 1200 MDT
                                           |
K index... +9.3  LI... +274.4              | K index... +5.8  LI... +272.5
CAPE... 0.0  CIN... -0.1                   | CAPE... +8.4  CIN... -48.2
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -58.1 -72.6  265  40 21   1.2   0.7 | -58.5 -73.3  270  39 20   0.8   0.5
 45000 -56.3 -69.3  270  41 21  -0.5  -0.3 | -57.3 -71.1  270  41 21  -0.8  -0.5
 40000 -60.3 -76.5  295  50 26  -2.6  -1.4 | -61.1 -78.0  290  50 26  -2.5  -1.4
 38000 -59.8 -75.6  300  52 27   4.4   2.4 | -60.5 -76.9  290  51 26   4.8   2.7
 36000 -56.8 -70.2  300  52 27   4.4   2.4 | -57.2 -71.0  295  51 26   4.9   2.7
 34000 -53.7 -64.7  300  50 26   7.3   4.0 | -53.7 -64.7  295  50 26   7.6   4.2
 32000 -49.2 -56.6  310  47 24   7.4   4.1 | -49.1 -56.4  295  48 25   7.7   4.2
 30000 -44.6 -48.3  315  44 22   8.3   4.5 | -44.2 -47.6  295  47 24   9.1   5.0
 29000 -42.1 -43.8  315  41 21   8.3   4.5 | -41.5 -42.7  290  46 24   9.1   5.0
 28000 -39.6 -39.3  315  39 20   8.3   4.6 | -38.8 -37.8  290  45 23   9.1   5.0
 27000 -37.1 -34.8  315  37 19   8.2   4.5 | -36.1 -33.0  285  43 22   7.8   4.3
 26000 -34.7 -30.5  315  35 18   8.2   4.5 | -33.8 -28.8  285  39 20   7.8   4.3
 25000 -32.2 -26.0  310  34 17   8.2   4.5 | -31.4 -24.5  285  35 18   7.8   4.3
 24000 -29.8 -21.6  310  32 17   7.7   4.2 | -29.1 -20.4  280  30 16   6.8   3.7
 23000 -27.6 -17.7  305  29 15   7.4   4.0 | -27.3 -17.1  280  29 15   6.2   3.4
 22000 -25.3 -13.5  300  26 13   7.4   4.0 | -25.4 -13.7  280  27 14   6.2   3.4
 21000 -23.2  -9.8  295  23 12   5.9   3.2 | -23.5 -10.3  285  26 13   5.9   3.2
 20000 -21.5  -6.7  295  21 11   5.9   3.2 | -21.8  -7.2  285  25 13   5.9   3.2
 19500 -20.6  -5.1  300  20 11   5.9   3.2 | -20.9  -5.6  285  24 13   5.9   3.2
 19000 -19.7  -3.5  300  19 10   5.9   3.2 | -20.0  -4.0  285  24 12   5.8   3.2
 18500 -18.2  -0.8  300  18  9   7.7   4.2 | -19.1  -2.4  285  24 12   8.0   4.4
 18000 -17.1   1.2  300  17  9   7.6   4.2 | -17.2   1.0  285  23 12   8.4   4.6
 17500 -15.9   3.4  305  16  8   8.5   4.7 | -15.9   3.4  285  23 12   8.8   4.8
 17000 -14.6   5.7  305  15  8   8.6   4.7 | -14.6   5.7  285  22 11   8.8   4.8
 16500 -13.3   8.1  310  14  7   8.4   4.6 | -13.3   8.1  285  21 11   8.6   4.7
 16000 -12.1  10.2  310  13  7   8.2   4.5 | -12.0  10.4  285  19 10   8.5   4.6
 15500 -10.9  12.4  310  13  7   8.3   4.5 | -10.7  12.7  280  17  9   8.3   4.6
 15000  -9.6  14.7  310  12  6   8.7   4.8 |  -9.5  14.9  280  15  8   7.8   4.3
 14500  -8.3  17.1  315  11  6   8.7   4.8 |  -8.4  16.9  275  13  7   7.8   4.3
 14000  -7.0  19.4  315  10  5   8.5   4.6 |  -7.1  19.2  275  11  6   8.6   4.7
 13500  -5.8  21.6  320   9  5   8.5   4.7 |  -5.9  21.4  275  10  5   8.5   4.7
 13000  -4.5  23.9  325   8  4   8.6   4.7 |  -4.5  23.9  280   9  5   9.4   5.2
 12500  -3.2  26.2  325   9  5   8.6   4.7 |  -3.1  26.4  285  10  5   9.4   5.1
 12000  -1.9  28.6  330   9  5   8.8   4.9 |  -1.7  28.9  290  10  5   9.3   5.1
 11500  -0.6  30.9  335   9  5   8.8   4.8 |  -0.4  31.3  295  10  5   9.4   5.2
 11000   0.8  33.4  335  10  5   9.9   5.4 |   1.0  33.8  300  10  5   8.8   4.8
 10500   2.2  36.0  335  11  6  11.1   6.1 |   2.3  36.1  305  11  6   9.7   5.3
 10250   3.0  37.4  340  12  6   5.3   2.9 |   3.0  37.4  305  12  6   5.0   2.7
 10000   3.2  37.8  340  12  6   6.5   3.6 |   3.2  37.8  310  12  6   6.3   3.5
  9750   4.1  39.4  340  13  6  12.9   7.1 |   4.0  39.2  310  12  6  11.9   6.5
  9500   4.9  40.8  340  13  7  12.1   6.6 |   4.8  40.6  315  12  6  10.9   6.0
  9250   5.8  42.4  340  14  7   9.0   4.9 |   5.6  42.1  315  12  6   8.7   4.8
  9000   6.3  43.3  335  14  7   7.5   4.1 |   6.1  43.0  320  11  6   7.5   4.1
  8750   7.1  44.8  335  15  8  10.6   5.8 |   6.7  44.1  320  11  6   9.4   5.2
  8500   7.8  46.0  330  16  8  10.2   5.6 |   7.4  45.3  325  11  6   9.0   5.0
  8250   8.6  47.5  330  17  9   9.5   5.2 |   8.0  46.4  325  11  6   8.6   4.7
  8000   9.3  48.7  325  17  9   8.9   4.9 |   8.7  47.7  330  10  5   8.5   4.6
  7750  10.0  50.0  325  18  9   9.1   5.0 |   9.3  48.7  335  10  5   8.9   4.9
  7500  10.6  51.1  320  19 10   8.6   4.7 |  10.0  50.0  335  10  5   9.2   5.1
  7250  11.2  52.2  320  19 10   7.8   4.3 |  10.6  51.1  340   9  4   9.5   5.2
  7000  11.8  53.2  315  19 10   7.4   4.1 |  11.3  52.3  340   8  4   9.5   5.2
  6750  12.3  54.1  315  19 10   8.2   4.5 |  12.0  53.6  340   7  3   8.8   4.8
  6500  12.8  55.0  310  20 10  -0.1  -0.1 |  12.6  54.7  345   6  3   9.8   5.4
  6250  12.3  54.1  305  18  9  -7.6  -4.2 |  13.4  56.1  345   6  3  11.4   6.3
  6000  11.9  53.4  295  16  8  -3.8  -2.1 |  14.3  57.7  345   5  3  10.2   5.6
  5750  11.4  52.5  290  15  8  -9.3  -5.1 |  15.1  59.2  345   5  3  12.6   6.9
  5500  10.0  50.0  275  11  6 -28.6 -15.7 |  16.2  61.2  345   5  3  19.8  10.9

           03/22/2015 at 1500 MDT          |       03/22/2015 at 1800 MDT
                                           |
K index... +15.9  LI... +272.9             | K index... +22.0  LI... +272.2
CAPE... +4.8  CIN... -24.6                 | CAPE... +41.1  CIN... -31.3
                                           |
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 -58.7 -73.7  270  41 21   1.1   0.6 | -58.5 -73.3  275  40 21   0.5   0.3
 45000 -57.1 -70.8  275  47 24  -1.1  -0.6 | -57.7 -71.9  280  50 26  -1.3  -0.7
 40000 -61.5 -78.7  285  55 28  -2.9  -1.6 | -62.1 -79.8  280  58 30  -3.0  -1.6
 38000 -60.7 -77.3  285  56 29   5.6   3.1 | -61.3 -78.3  285  59 31   5.6   3.1
 36000 -57.3 -71.1  290  54 28   5.6   3.1 | -57.9 -72.2  285  60 31   5.7   3.1
 34000 -53.2 -63.8  290  52 27   7.4   4.0 | -54.2 -65.6  285  59 31   7.8   4.3
 32000 -48.8 -55.8  290  50 26   7.4   4.0 | -49.0 -56.2  285  56 29   7.7   4.2
 30000 -44.1 -47.4  290  48 24   8.7   4.8 | -44.1 -47.4  285  52 27   9.2   5.0
 29000 -41.4 -42.5  290  45 23   8.7   4.8 | -41.3 -42.3  285  49 25   9.2   5.0
 28000 -38.8 -37.8  285  43 22   8.7   4.8 | -38.6 -37.5  285  46 24   9.2   5.0
 27000 -36.2 -33.2  280  41 21   8.4   4.6 | -35.9 -32.6  285  44 23   8.3   4.6
 26000 -33.7 -28.7  280  39 20   8.4   4.6 | -33.4 -28.1  285  43 22   8.3   4.6
 25000 -31.2 -24.2  275  37 19   8.4   4.6 | -31.0 -23.8  280  43 22   8.3   4.6
 24000 -28.7 -19.7  270  35 18   6.8   3.7 | -28.5 -19.3  280  42 22   6.6   3.6
 23000 -27.0 -16.6  275  34 18   5.9   3.3 | -26.8 -16.2  275  41 21   5.7   3.1
 22000 -25.2 -13.4  280  34 18   5.9   3.3 | -25.1 -13.2  275  40 20   5.7   3.1
 21000 -23.3  -9.9  280  34 17   7.3   4.0 | -23.3  -9.9  270  38 20   7.5   4.1
 20000 -21.2  -6.2  280  33 17   7.2   3.9 | -21.1  -6.0  265  35 18   7.4   4.0
 19500 -20.1  -4.2  280  32 17   7.2   3.9 | -20.0  -4.0  265  33 17   7.4   4.0
 19000 -19.1  -2.4  280  32 16   7.2   3.9 | -19.0  -2.2  260  32 16   7.3   4.0
 18500 -18.0  -0.4  280  31 16   7.9   4.3 | -17.8  -0.0  260  30 15   8.2   4.5
 18000 -16.8   1.8  280  29 15   8.0   4.4 | -16.6   2.1  260  27 14   8.3   4.6
 17500 -15.0   5.0  280  26 13   8.1   4.4 | -15.4   4.3  260  25 13   8.3   4.5
 17000 -13.8   7.2  280  25 13   8.1   4.4 | -13.6   7.5  260  23 12   8.2   4.5
 16500 -12.6   9.3  280  23 12   8.1   4.4 | -12.4   9.7  255  22 11   8.0   4.4
 16000 -11.4  11.5  280  22 11   8.1   4.4 | -11.3  11.7  255  21 11   7.8   4.3
 15500 -10.2  13.6  280  20 10   8.1   4.5 | -10.1  13.8  255  20 10   7.8   4.3
 15000  -9.0  15.8  280  19 10   8.2   4.5 |  -8.9  16.0  250  19 10   8.2   4.5
 14500  -7.7  18.1  280  17  9   8.2   4.5 |  -7.7  18.1  245  18  9   8.1   4.4
 14000  -6.5  20.3  280  16  8   8.5   4.7 |  -6.5  20.3  240  18  9   8.9   4.9
 13500  -5.2  22.6  280  15  8   8.5   4.6 |  -5.2  22.6  235  16  8   8.8   4.8
 13000  -3.9  25.0  275  14  7   9.2   5.0 |  -3.9  25.0  230  15  8   8.7   4.8
 12500  -2.6  27.3  275  13  7   9.2   5.1 |  -2.5  27.5  230  14  7   8.7   4.8
 12000  -1.2  29.8  275  12  6   8.6   4.7 |  -1.2  29.8  225  13  6   9.1   5.0
 11500   0.0  32.0  270  10  5   8.6   4.7 |   0.2  32.4  215  10  5   9.2   5.0
 11000   1.2  34.2  265   7  4   7.5   4.1 |   1.5  34.7  205   8  4   8.8   4.8
 10500   2.3  36.1  250   3  2   8.1   4.4 |   2.8  37.0  195   7  3   9.3   5.1
 10250   2.9  37.2  210   1  1   5.0   2.8 |   3.4  38.1  185   6  3   6.1   3.4
 10000   3.2  37.8  195   1  1   6.9   3.8 |   3.8  38.8  185   6  3   7.3   4.0
  9750   3.9  39.0  160   1  1  11.1   6.1 |   4.6  40.3  180   6  3  11.2   6.1
  9500   4.7  40.5  135   2  1  10.6   5.8 |   5.4  41.7  170   5  3  10.8   5.9
  9250   5.4  41.7  115   2  1   8.6   4.7 |   6.1  43.0  165   5  3   8.6   4.7
  9000   6.0  42.8  120   2  1   8.5   4.7 |   6.7  44.1  160   5  2   8.1   4.5
  8750   6.8  44.2  115   2  1  10.9   6.0 |   7.4  45.3  155   4  2  10.3   5.7
  8500   7.5  45.5  115   3  1  10.4   5.7 |   8.1  46.6  145   4  2   9.8   5.4
  8250   8.3  46.9  115   3  1  10.2   5.6 |   8.9  48.0  140   4  2   9.9   5.4
  8000   9.1  48.4  110   3  1  10.0   5.5 |   9.6  49.3  135   4  2   9.6   5.3
  7750   9.8  49.6  110   3  1  10.1   5.5 |  10.3  50.5  135   4  2   9.4   5.1
  7500  10.6  51.1  110   3  1  10.2   5.6 |  11.0  51.8  130   4  2   9.4   5.2
  7250  11.4  52.5  110   3  1  10.3   5.7 |  11.7  53.1  130   4  2   9.8   5.4
  7000  12.1  53.8  110   2  1  10.3   5.7 |  12.4  54.3  125   4  2  10.0   5.5
  6750  12.9  55.2  110   2  1   9.4   5.2 |  13.2  55.8  125   3  2   9.4   5.2
  6500  13.6  56.5  105   2  1   9.9   5.4 |  13.8  56.8  120   3  2   9.6   5.3
  6250  14.4  57.9  105   2  1  11.3   6.2 |  14.6  58.3  120   3  2  10.1   5.5
  6000  15.2  59.4  105   2  1  10.1   5.6 |  15.3  59.5  115   3  1   9.9   5.4
  5750  16.0  60.8  100   2  1  12.2   6.7 |  16.1  61.0  115   3  1   9.7   5.3
  5500  17.1  62.8  100   2  1  19.7  10.8 |  16.7  62.1  115   3  1   9.5   5.2
________________________________________________________________________________

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

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

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

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

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

DEFINITIONS:

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

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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