Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 220047
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1747 MST Friday, November 21, 2014

This forecast is for Saturday, November 22, 2014:

If the trigger temperature of 56.9 F/13.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 470 ft/min (2.4 m/s)
   Maximum height of thermals.................. 12277 ft MSL (6990 ft AGL)

Forecast maximum temperature................... 61.0 F/16.6 C
Time of trigger temperature.................... 1100 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8328 ft MSL (3041 ft AGL)
Thermal soaring outlook for Sunday 11/23....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 17361 ft MSL (12074 ft AGL)
Wave soaring outlook for Sunday 11/23.......... Fair

Remarks... Westerly flow aloft will strengthen over the next 24 hours ahead of a
           very moist pacific storm system.

Sunrise/Sunset.................... 06:52:04 / 16:39:10 MST
Total possible sunshine........... 9 hr 47 min 6 sec (587 min 6 sec)
Altitude of sun at 11:45:47 MST... 30.05 degrees

Upper air data from numerical model forecast valid on 11/22/2014 at 0500 MST

Freezing level.................. 5396 ft MSL (109 ft AGL)
Additional freezing level....... 10080 ft MSL (4793 ft AGL)
Convective condensation level... 17032 ft MSL (11745 ft AGL)
Lifted condensation level....... 16114 ft MSL (10827 ft AGL)
Lifted index.................... +6.4
K index......................... -4.3

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  -62.3 -80.1   290   31   16   1.0   0.5      M     M       M      M    M
 45000  -60.9 -77.6   300   34   17   1.1   0.6      M     M       M      M    M
 40000  -58.5 -73.3   320   39   20   1.6   0.9      M     M       M      M    M
 38000  -57.1 -70.8   330   41   21   3.7   2.0      M     M       M      M    M
 36000  -54.9 -66.8   340   43   22   3.7   2.0      M     M       M      M    M
 34000  -52.5 -62.5   345   45   23   6.6   3.6      M     M       M      M    M
 32000  -47.8 -54.0   350   46   24   6.9   3.8      M     M       M      M    M
 30000  -43.5 -46.3   350   47   24   8.4   4.6   32.4  90.3    12.2      M    M
 29000  -41.0 -41.8   350   45   23   8.4   4.6   31.8  89.2    11.9      M    M
 28000  -38.4 -37.1   350   44   23   8.4   4.6   31.3  88.3    11.7      M    M
 27000  -35.9 -32.6   350   42   22   8.3   4.5   30.9  87.7    11.5      M    M
 26000  -33.5 -28.3   350   38   20   7.8   4.3   30.1  86.2    11.0      M    M
 25000  -31.2 -24.2   345   34   18   7.8   4.3   29.4  84.9    10.6      M    M
 24000  -28.8 -19.8   345   30   15   7.9   4.3   28.8  83.8    10.2      M    M
 23000  -26.7 -16.1   335   28   15   6.8   3.8   27.7  81.9     9.5      M    M
 22000  -24.6 -12.3   325   28   15   6.9   3.8   26.7  80.0     8.7      M    M
 21000  -22.6  -8.7   315   29   15   6.1   3.3   25.7  78.3     8.0      M    M
 20000  -21.1  -6.0   300   25   13   4.7   2.6   23.9  75.0     6.6      M    M
 19500  -20.4  -4.7   290   23   12   4.7   2.6   23.0  73.4     5.8      M    M
 19000  -19.7  -3.5   280   22   11   4.7   2.6   22.1  71.8     5.1      M    M
 18500  -19.0  -2.2   270   22   11   4.7   2.6   21.3  70.3     4.4      M    M
 18000  -18.3  -0.9   260   23   12   5.1   2.8   20.5  68.8     3.7      M    M
 17500  -17.5   0.5   255   23   12   5.0   2.7   19.7  67.4     3.0      M    M
 17000  -16.7   1.9   250   24   12   6.9   3.8   19.0  66.1     2.4      M    M
 16500  -15.6   3.9   250   24   12   7.3   4.0   18.5  65.4     2.1      M    M
 16000  -13.9   7.0   250   24   13   8.3   4.6   18.0  64.4     1.6      M    M
 15500  -12.7   9.1   250   24   12   8.3   4.5   17.7  63.9     1.3      M    M
 15000  -11.5  11.3   250   24   12   8.2   4.5   17.5  63.5     1.1      M    M
 14500  -10.2  13.6   255   24   12   8.3   4.5   17.2  63.0     0.9      M    M
 14000   -9.0  15.8   255   24   12   8.4   4.6   17.0  62.6     0.7      M    M
 13500   -7.7  18.1   260   24   12   8.6   4.7   16.8  62.2     0.5      M    M
 13000   -6.4  20.5   260   25   13   8.5   4.6   16.6  61.9     0.3      M    M
 12500   -5.2  22.6   265   25   13   8.2   4.5   16.4  61.4     0.1      M    M
 12000   -4.0  24.8   265   25   13   7.9   4.4   16.1  61.0    -0.2    535  2.7
 11500   -2.9  26.8   265   24   13   7.3   4.0   15.7  60.3    -0.5    487  2.5
 11000   -1.8  28.8   265   24   12   7.0   3.9   15.4  59.6    -0.9    439  2.2
 10500   -0.8  30.6   265   22   11   6.2   3.4   14.8  58.7    -1.4    395  2.0
 10250   -0.3  31.5   270   22   11   7.2   4.0   14.6  58.3    -1.7    374  1.9
 10000    0.3  32.5   270   21   11   8.7   4.8   14.5  58.0    -1.8    348  1.8
  9750    0.9  33.6   270   20   10   8.1   4.5   14.4  57.8    -1.9    322  1.6
  9500    1.5  34.7   270   19   10   7.6   4.2   14.2  57.6    -2.1    297  1.5
  9250    2.0  35.6   270   18    9   7.8   4.3   14.0  57.3    -2.2    273  1.4
  9000    2.6  36.7   270   18    9   7.5   4.1   13.9  57.0    -2.4    248  1.3
  8750    3.1  37.6   270   18    9   7.0   3.8   13.7  56.6    -2.6    225  1.1
  8500    3.6  38.5   270   18    9   6.9   3.8   13.5  56.2    -2.8    203  1.0
  8250    4.2  39.6   270   17    9   6.9   3.8   13.2  55.8    -3.1    180  0.9
  8000    4.6  40.3   270   16    8   6.7   3.7   13.0  55.4    -3.3    158  0.8
  7750    5.1  41.2   270   15    8   5.9   3.3   12.8  55.0    -3.6    137  0.7
  7500    5.5  41.9   270   14    7   5.7   3.1   12.4  54.4    -3.9    117  0.6
  7250    5.9  42.6   270   13    7   5.5   3.0   12.1  53.8    -4.3     97  0.5
  7000    6.3  43.3   270   11    6   4.8   2.6   11.8  53.2    -4.6     79  0.4
  6750    6.7  44.1   270    9    5   5.4   2.9   11.4  52.5    -5.0     60  0.3
  6500    7.0  44.6   265    7    4   2.4   1.3   11.0  51.8    -5.4     43  0.2
  6250    6.8  44.2   260    7    3  -8.9  -4.9   10.1  50.1    -6.4     42  0.2
  6000    5.8  42.4   250    7    4 -13.7  -7.5    8.4  47.0    -8.1     64  0.3
  5750    4.7  40.5   240    8    4 -17.4  -9.5    6.6  43.8   -10.0     89  0.5
  5500    2.6  36.7   230   12    6 -42.6 -23.4    3.7  38.7   -12.8    146  0.7

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

           11/22/2014 at 0800 MST          |       11/22/2014 at 1100 MST
                                           |
K index... -9.9  LI... +8.7                | K index... -8.4  LI... +7.4
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 -62.0 -79.6  285  29 15   1.1   0.6 | -60.7 -77.3  290  41 21   1.4   0.8
 45000 -60.3 -76.5  290  30 15   0.8   0.4 | -58.7 -73.7  295  51 26   1.0   0.6
 40000 -60.5 -76.9  305  35 18  -0.1  -0.1 | -59.0 -74.2  310  49 25  -0.2  -0.1
 38000 -58.8 -73.8  315  37 19   6.1   3.3 | -57.8 -72.0  310  46 24   4.5   2.5
 36000 -55.2 -67.4  325  41 21   6.1   3.3 | -55.1 -67.2  310  42 21   4.5   2.5
 34000 -51.5 -60.7  330  45 23   6.9   3.8 | -51.7 -61.1  310  37 19   7.4   4.0
 32000 -46.9 -52.4  330  42 22   6.8   3.7 | -47.2 -53.0  305  35 18   7.4   4.1
 30000 -42.7 -44.9  325  39 20   7.8   4.3 | -42.7 -44.9  305  33 17   8.0   4.4
 29000 -40.3 -40.5  325  37 19   7.9   4.3 | -40.3 -40.5  300  32 17   8.1   4.4
 28000 -38.0 -36.4  325  34 18   7.9   4.3 | -37.9 -36.2  300  31 16   8.1   4.4
 27000 -35.6 -32.1  325  32 16   7.9   4.4 | -35.4 -31.7  295  31 16   8.3   4.6
 26000 -33.2 -27.8  320  29 15   8.0   4.4 | -32.8 -27.0  290  30 15   8.7   4.8
 25000 -30.8 -23.4  315  27 14   8.0   4.4 | -30.2 -22.4  290  29 15   8.7   4.8
 24000 -28.4 -19.1  305  25 13   8.1   4.4 | -27.6 -17.7  285  29 15   8.7   4.8
 23000 -25.8 -14.4  305  26 13   8.9   4.9 | -25.1 -13.2  285  29 15   8.3   4.6
 22000 -23.1  -9.6  305  27 14   8.9   4.9 | -22.6  -8.7  285  29 15   8.4   4.6
 21000 -20.5  -4.9  305  28 14   8.5   4.7 | -20.1  -4.2  285  29 15   7.9   4.3
 20000 -18.1  -0.6  300  26 13   7.9   4.3 | -18.0  -0.4  290  27 14   7.1   3.9
 19500 -16.9   1.6  300  25 13   7.9   4.3 | -17.0   1.4  290  26 13   7.1   3.9
 19000 -15.7   3.7  300  24 12   7.9   4.3 | -15.9   3.4  290  25 13   7.1   3.9
 18500 -14.5   5.9  295  23 12   7.5   4.1 | -14.9   5.2  290  25 13   7.1   3.9
 18000 -13.7   7.3  290  22 11   4.1   2.2 | -13.9   7.0  290  23 12   6.0   3.3
 17500 -13.1   8.4  285  21 11   4.4   2.4 | -13.0   8.6  285  22 11   6.1   3.3
 17000 -12.5   9.5  275  20 10   1.9   1.1 | -12.1  10.2  280  21 11   5.1   2.8
 16500 -12.2  10.0  255  20 10   1.0   0.6 | -11.0  12.2  270  21 11   4.9   2.7
 16000 -11.9  10.6  245  21 11   3.9   2.2 | -10.3  13.5  265  20 11   3.7   2.0
 15500 -11.3  11.7  240  20 10   4.1   2.2 |  -9.7  14.5  260  19 10   3.6   2.0
 15000 -10.6  12.9  235  19 10   5.6   3.1 |  -9.2  15.4  255  18  9   4.5   2.4
 14500  -9.7  14.5  235  16  8   6.5   3.6 |  -8.4  16.9  250  16  8   5.2   2.8
 14000  -8.7  16.3  235  14  7   7.4   4.0 |  -7.6  18.3  250  13  7   6.1   3.4
 13500  -7.4  18.7  240  12  6   8.6   4.7 |  -6.5  20.3  250  11  6   8.4   4.6
 13000  -6.1  21.0  245  10  5   8.9   4.9 |  -5.2  22.6  250   9  4   8.5   4.7
 12500  -4.7  23.5  255  10  5   9.7   5.3 |  -3.9  25.0  260   8  4   9.4   5.1
 12000  -3.3  26.1  270  10  5   9.4   5.2 |  -2.5  27.5  275   8  4   9.2   5.0
 11500  -2.0  28.4  280  12  6   8.1   4.4 |  -1.3  29.7  285  10  5   7.4   4.0
 11000  -0.8  30.6  285  16  8   7.6   4.2 |  -0.2  31.6  295  15  8   7.3   4.0
 10500   0.1  32.2  285  20 10   5.0   2.7 |   0.6  33.1  290  19 10   4.0   2.2
 10250   0.5  32.9  285  22 11   5.6   3.1 |   0.9  33.6  290  22 11   4.4   2.4
 10000   0.9  33.6  285  24 13   5.7   3.1 |   1.2  34.2  290  24 13   3.6   2.0
  9750   1.3  34.3  285  26 13   4.1   2.2 |   1.4  34.5  290  26 13   2.2   1.2
  9500   1.5  34.7  285  27 14   3.1   1.7 |   1.5  34.7  285  27 14   1.6   0.9
  9250   1.7  35.1  285  28 15   3.6   1.9 |   1.6  34.9  285  27 14   2.0   1.1
  9000   2.0  35.6  285  29 15   2.9   1.6 |   1.7  35.1  285  28 14   1.3   0.7
  8750   2.1  35.8  280  28 15   2.4   1.3 |   1.8  35.2  285  27 14   2.7   1.5
  8500   2.3  36.1  280  27 14   2.7   1.5 |   2.1  35.8  280  25 13   4.6   2.5
  8250   2.5  36.5  280  26 13   2.7   1.5 |   2.4  36.3  280  22 11   3.8   2.1
  8000   2.7  36.9  280  24 12   4.4   2.4 |   2.7  36.9  280  19 10   5.8   3.2
  7750   3.1  37.6  275  20 10   5.2   2.8 |   3.2  37.8  275  16  8   6.7   3.7
  7500   3.4  38.1  270  17  9   4.1   2.2 |   3.6  38.5  275  13  7   5.6   3.1
  7250   3.7  38.7  265  15  8   5.6   3.1 |   4.1  39.4  270  11  6   6.1   3.4
  7000   4.2  39.6  260  12  6   7.9   4.3 |   4.5  40.1  265   9  4   6.6   3.6
  6750   4.8  40.6  255  11  5   7.4   4.1 |   5.0  41.0  250   7  4   6.3   3.5
  6500   5.3  41.5  245   9  5   6.3   3.4 |   5.5  41.9  230   6  3   6.1   3.3
  6250   5.6  42.1  230   8  4  -3.1  -1.7 |   5.9  42.6  210   6  3   5.4   3.0
  6000   4.9  40.8  220   9  5  -8.5  -4.7 |   6.3  43.3  200   7  3   5.4   3.0
  5750   4.2  39.6  215  11  5 -15.1  -8.3 |   6.6  43.9  190   7  4   0.9   0.5
  5500   2.2  36.0  205  13  7 -39.8 -21.8 |   6.2  43.2  185   6  3  -6.0  -3.3

           11/22/2014 at 1400 MST          |       11/22/2014 at 1700 MST
                                           |
K index... +4.6  LI... +5.8                | K index... +13.6  LI... +2.5
CAPE... 0.0  CIN... -0.1                   | CAPE... 0.0  CIN... -1.0
                                           |
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 -62.5 -80.5  295  47 24   1.8   1.0 | -62.2 -80.0  300  55 28   4.0   2.2
 45000 -59.6 -75.3  300  52 27   1.7   0.9 | -56.2 -69.2  305  71 37   3.3   1.8
 40000 -57.5 -71.5  295  58 30   1.4   0.8 | -55.8 -68.4  295  66 34   0.2   0.1
 38000 -56.3 -69.3  290  54 28   2.7   1.5 | -55.1 -67.2  290  62 32   2.9   1.6
 36000 -54.7 -66.5  285  44 23   2.7   1.5 | -53.3 -63.9  285  54 28   2.9   1.6
 34000 -52.9 -63.2  275  34 18   6.3   3.5 | -51.2 -60.2  280  45 23   6.1   3.3
 32000 -48.2 -54.8  270  32 16   6.9   3.8 | -47.7 -53.9  265  41 21   5.7   3.2
 30000 -43.8 -46.8  265  30 16   8.9   4.9 | -44.1 -47.4  250  41 21   8.2   4.5
 29000 -41.1 -42.0  265  31 16   8.9   4.9 | -41.7 -43.1  250  41 21   8.0   4.4
 28000 -38.5 -37.3  265  32 17   8.9   4.9 | -39.3 -38.7  245  41 21   8.0   4.4
 27000 -35.8 -32.4  265  33 17   8.6   4.7 | -36.8 -34.2  245  41 21   8.0   4.4
 26000 -33.4 -28.1  275  34 18   7.9   4.3 | -34.4 -29.9  250  39 20   8.0   4.4
 25000 -31.0 -23.8  280  35 18   7.9   4.3 | -32.0 -25.6  260  38 20   8.0   4.4
 24000 -28.7 -19.7  285  37 19   7.9   4.3 | -29.6 -21.3  265  38 19   8.1   4.5
 23000 -26.3 -15.3  285  37 19   8.1   4.4 | -27.4 -17.3  275  37 19   7.0   3.8
 22000 -23.9 -11.0  280  37 19   8.1   4.5 | -25.3 -13.5  280  37 19   7.0   3.8
 21000 -21.5  -6.7  275  37 19   8.2   4.5 | -23.2  -9.8  285  37 19   7.1   3.9
 20000 -19.1  -2.4  270  33 17   8.2   4.5 | -21.1  -6.0  285  34 17   7.4   4.1
 19500 -17.8  -0.0  270  31 16   8.2   4.5 | -20.0  -4.0  285  32 16   7.5   4.1
 19000 -16.6   2.1  265  30 15   8.2   4.5 | -18.9  -2.0  285  30 16   7.5   4.1
 18500 -15.4   4.3  265  28 14   8.2   4.5 | -17.8  -0.0  280  28 15   7.4   4.1
 18000 -14.3   6.3  265  26 14   6.6   3.6 | -16.6   2.1  280  26 14   8.4   4.6
 17500 -13.3   8.1  265  25 13   6.8   3.7 | -15.4   4.3  275  24 13   8.3   4.6
 17000 -12.3   9.9  265  23 12   5.9   3.2 | -14.2   6.4  275  23 12   8.3   4.5
 16500 -11.5  11.3  260  22 12   5.5   3.0 | -12.3   9.9  270  21 11   8.2   4.5
 16000 -10.2  13.6  260  21 11   5.2   2.9 | -11.1  12.0  270  19 10   8.0   4.4
 15500  -9.4  15.1  260  20 10   5.2   2.9 |  -9.9  14.2  270  18  9   7.9   4.3
 15000  -8.7  16.3  260  18  9   5.8   3.2 |  -8.8  16.2  270  16  8   7.7   4.2
 14500  -7.7  18.1  260  17  9   6.3   3.5 |  -7.6  18.3  275  15  8   7.3   4.0
 14000  -6.8  19.8  260  15  8   6.7   3.7 |  -6.6  20.1  275  14  7   7.3   4.0
 13500  -5.6  21.9  260  13  7   8.0   4.4 |  -5.4  22.3  280  14  7   7.8   4.3
 13000  -4.5  23.9  265  12  6   8.0   4.4 |  -4.2  24.4  285  15  8   7.8   4.3
 12500  -3.2  26.2  275  12  6   9.3   5.1 |  -3.1  26.4  285  16  8   7.0   3.8
 12000  -1.8  28.8  280  13  7   9.3   5.1 |  -2.1  28.2  285  18  9   7.1   3.9
 11500  -0.8  30.6  285  17  9   5.0   2.8 |  -1.1  30.0  285  21 11   7.0   3.8
 11000   0.0  32.0  290  22 11   5.5   3.0 |  -0.0  32.0  285  24 13   7.3   4.0
 10500   0.7  33.3  285  26 14   3.6   2.0 |   0.8  33.4  285  28 14   3.9   2.2
 10250   1.0  33.8  285  29 15   3.7   2.1 |   1.1  34.0  285  29 15   4.1   2.3
 10000   1.2  34.2  285  31 16   3.3   1.8 |   1.4  34.5  285  31 16   4.1   2.3
  9750   1.5  34.7  285  32 16   2.8   1.5 |   1.7  35.1  285  32 17   3.6   2.0
  9500   1.6  34.9  280  31 16   2.6   1.4 |   1.9  35.4  285  32 17   3.0   1.6
  9250   1.8  35.2  280  29 15   2.8   1.5 |   2.2  36.0  280  32 17   3.3   1.8
  9000   2.0  35.6  280  28 15   2.3   1.3 |   2.4  36.3  280  32 16   2.6   1.4
  8750   2.2  36.0  280  27 14   4.1   2.3 |   2.6  36.7  275  31 16   2.9   1.6
  8500   2.6  36.7  275  24 12   6.1   3.4 |   2.8  37.0  275  29 15   4.1   2.2
  8250   3.0  37.4  275  21 11   5.0   2.7 |   3.1  37.6  275  26 14   3.1   1.7
  8000   3.4  38.1  270  18  9   7.6   4.1 |   3.4  38.1  270  24 12   5.9   3.2
  7750   4.1  39.4  265  15  8   8.3   4.6 |   4.0  39.2  270  22 11   7.8   4.3
  7500   4.6  40.3  260  13  7   6.4   3.5 |   4.5  40.1  270  19 10   6.5   3.6
  7250   5.1  41.2  255  11  6   7.1   3.9 |   5.0  41.0  270  17  9   6.5   3.6
  7000   5.6  42.1  245  10  5   8.2   4.5 |   5.5  41.9  265  15  7   8.1   4.4
  6750   6.3  43.3  235   8  4   9.0   4.9 |   6.2  43.2  265  13  7   9.5   5.2
  6500   6.9  44.4  225   8  4   8.9   4.9 |   6.8  44.2  265  11  6   9.1   5.0
  6250   7.6  45.7  210   7  4   8.4   4.6 |   7.5  45.5  260  10  5   8.5   4.7
  6000   8.2  46.8  205   7  3   7.7   4.2 |   8.1  46.6  255   8  4   6.4   3.5
  5750   8.7  47.7  200   6  3   6.7   3.7 |   8.5  47.3  250   7  3   7.9   4.3
  5500   8.9  48.0  190   5  3   6.1   3.3 |   9.1  48.4  235   5  3   4.7   2.6
________________________________________________________________________________

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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