Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 151403
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0703 MST Wednesday, November 15, 2017

This forecast is for Wednesday, November 15, 2017:

If the trigger temperature of 53.4 F/11.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 83 ft/min (0.4 m/s)
   Maximum height of thermals.................. 9438 ft MSL (4103 ft AGL)

Forecast maximum temperature................... 54.0 F/12.7 C
Time of trigger temperature.................... 1230 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8596 ft MSL (3261 ft AGL)
Thermal soaring outlook for Thursday 11/16..... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Improving
Height of stable layer (12-18K ft MSL)......... 11972 ft MSL (6637 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 45157 ft MSL (39822 ft AGL)
Wave soaring outlook for Thursday 11/16........ Good

Remarks...

Sunrise/Sunset.................... 06:44:43 / 16:43:33 MST
Total possible sunshine........... 9 hr 58 min 51 sec (598 min 51 sec)
Altitude of sun at 11:44:08 MST... 31.44 degrees

Upper air data from numerical model forecast valid on 11/15/2017 at 0500 MST

Freezing level.................. 5353 ft MSL (18 ft AGL)
Additional freezing level....... 6755 ft MSL (1420 ft AGL)
Convective condensation level... 17761 ft MSL (12426 ft AGL)
Lifted condensation level....... 13513 ft MSL (8178 ft AGL)
Lifted index.................... +9.5
K index......................... -20.1

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  -63.6 -82.5   295   53   27   1.6   0.9      M     M       M      M    M
 45000  -61.2 -78.2   295   64   33   0.5   0.2      M     M       M      M    M
 40000  -60.5 -76.9   305   64   33   0.4   0.2      M     M       M      M    M
 38000  -58.8 -73.8   310   62   32   4.2   2.3      M     M       M      M    M
 36000  -56.3 -69.3   315   60   31   4.2   2.3      M     M       M      M    M
 34000  -53.1 -63.6   315   57   29   8.7   4.8      M     M       M      M    M
 32000  -47.1 -52.8   315   54   28   8.9   4.9      M     M       M      M    M
 30000  -41.8 -43.2   310   52   27   8.6   4.7   34.0  93.3    16.4      M    M
 29000  -39.3 -38.7   310   51   26   8.6   4.7   33.6  92.4    16.2      M    M
 28000  -36.7 -34.1   310   50   26   8.6   4.7   33.2  91.7    16.2      M    M
 27000  -34.2 -29.6   310   49   25   7.7   4.2   32.7  90.9    16.0      M    M
 26000  -31.9 -25.4   315   48   25   7.7   4.2   31.9  89.3    15.5      M    M
 25000  -29.6 -21.3   315   47   24   7.8   4.3   31.1  88.0    15.1      M    M
 24000  -27.3 -17.1   315   46   24   6.9   3.8   30.4  86.8    14.7      M    M
 23000  -25.3 -13.5   315   43   22   6.8   3.7   29.3  84.7    13.9      M    M
 22000  -23.2  -9.8   315   41   21   6.8   3.7   28.2  82.8    13.2      M    M
 21000  -21.2  -6.2   320   38   20   6.8   3.7   27.2  81.0    12.5      M    M
 20000  -19.1  -2.4   320   35   18   6.8   3.7   26.1  79.0    11.7      M    M
 19500  -18.1  -0.6   320   33   17   6.8   3.7   25.6  78.1    11.4      M    M
 19000  -17.1   1.2   320   32   16   6.8   3.7   25.1  77.2    11.0      M    M
 18500  -16.0   3.2   320   30   16   7.3   4.0   24.7  76.4    10.7      M    M
 18000  -14.9   5.2   320   29   15   7.3   4.0   24.2  75.6    10.4      M    M
 17500  -13.3   8.1   320   27   14   7.9   4.4   23.6  74.6    10.0      M    M
 17000  -12.1  10.2   320   27   14   7.9   4.4   23.3  74.0     9.8      M    M
 16500  -10.9  12.4   325   27   14   7.9   4.3   23.0  73.5     9.6      M    M
 16000   -9.7  14.5   325   28   14   7.9   4.3   22.7  72.9     9.3      M    M
 15500   -8.5  16.7   325   28   14   7.8   4.3   22.4  72.3     9.1      M    M
 15000   -7.4  18.7   330   28   15   7.8   4.3   22.1  71.7     8.8      M    M
 14500   -6.2  20.8   330   29   15   7.9   4.4   21.7  71.1     8.6      M    M
 14000   -5.1  22.8   330   28   14   6.5   3.5   21.3  70.4     8.2      M    M
 13500   -4.1  24.6   330   27   14   6.8   3.7   20.8  69.4     7.8      M    M
 13000   -3.3  26.1   325   25   13   4.4   2.4   20.1  68.3     7.2      M    M
 12500   -2.7  27.1   320   22   11   4.4   2.4   19.3  66.7     6.4      M    M
 12000   -2.1  28.2   315   18    9   3.1   1.7   18.3  65.0     5.6      M    M
 11500   -1.7  28.9   305   15    8   3.0   1.6   17.2  63.0     4.5      M    M
 11000   -1.2  29.8   285   11    6   3.6   2.0   16.2  61.1     3.5      M    M
 10500   -0.7  30.7   245   11    5   3.7   2.0   15.2  59.4     2.6      M    M
 10250   -0.5  31.1   230   12    6   3.5   1.9   14.7  58.5     2.1      M    M
 10000   -0.3  31.5   205   21   11   2.0   1.1   14.2  57.6     1.6      M    M
  9750   -0.2  31.6   195   28   15   0.4   0.2   13.5  56.3     0.9      M    M
  9500   -0.2  31.6   190   33   17   0.8   0.5   12.8  55.0     0.2      M    M
  9250   -0.2  31.6   190   38   20  -1.2  -0.7   12.1  53.7    -0.5    278  1.4
  9000   -0.4  31.3   185   53   27  -3.4  -1.8   11.1  51.9    -1.5    278  1.4
  8750   -0.7  30.7   185   64   33  -1.3  -0.7   10.1  50.2    -2.4    276  1.4
  8500   -0.7  30.7   180   64   33  -0.4  -0.2    9.3  48.8    -3.2    271  1.4
  8250   -0.8  30.6   180   55   28  -0.6  -0.3    8.5  47.3    -4.0    266  1.3
  8000   -0.8  30.6   180   33   17  -0.6  -0.4    7.7  45.9    -4.8    260  1.3
  7750   -0.9  30.4   170   10    5  -0.0  -0.0    6.9  44.5    -5.6    254  1.3
  7500   -0.8  30.6   125    3    2   2.3   1.2    6.3  43.3    -6.3    244  1.2
  7250   -0.6  30.9   135    5    2   3.5   1.9    5.8  42.4    -6.8    230  1.2
  7000   -0.3  31.5   145    7    4   3.3   1.8    5.3  41.5    -7.3    215  1.1
  6750   -0.1  31.8   150   10    5   3.8   2.1    4.8  40.6    -7.8    200  1.0
  6500    0.3  32.5   170   20   10   5.1   2.8    4.4  39.9    -8.2    183  0.9
  6250    0.7  33.3   175   31   16   5.6   3.0    4.1  39.3    -8.6    164  0.8
  6000    1.1  34.0   175   42   22   5.5   3.0    3.7  38.7    -8.9    144  0.7
  5750    1.3  34.3   175   50   26  -2.0  -1.1    3.2  37.8    -9.4    130  0.7
  5500    0.6  33.1   180   54   28 -14.6  -8.0    1.8  35.3   -10.8    142  0.7

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

           11/15/2017 at 0800 MST          |       11/15/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +7.1        | CAPE...     0.0    LI...       +6.8
CINH...    -0.0    K Index... -15.1        | CINH...    -0.0    K Index... -10.2
                                           |
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 -64.6 -84.3  280  49 25   1.3   0.7 | -64.5 -84.1  300  53 27   1.1   0.6
 45000 -62.5 -80.5  285  59 31   0.9   0.5 | -62.8 -81.0  300  64 33   1.0   0.5
 40000 -61.1 -78.0  285  52 27   1.0   0.5 | -61.3 -78.3  300  56 29   1.0   0.5
 38000 -58.8 -73.8  285  49 25   5.2   2.9 | -58.9 -74.0  300  51 26   5.7   3.1
 36000 -55.7 -68.3  285  44 23   5.2   2.9 | -55.4 -67.7  295  46 23   5.7   3.1
 34000 -52.0 -61.6  285  41 21   8.3   4.5 | -51.6 -60.9  295  41 21   8.1   4.4
 32000 -47.0 -52.6  285  39 20   8.3   4.6 | -46.1 -51.0  295  38 20   8.1   4.5
 30000 -41.4 -42.5  285  37 19   8.2   4.5 | -41.2 -42.2  300  36 19   8.2   4.5
 29000 -39.0 -38.2  285  36 18   8.2   4.5 | -38.7 -37.7  300  35 18   8.2   4.5
 28000 -36.5 -33.7  285  35 18   8.2   4.5 | -36.3 -33.3  300  35 18   8.2   4.5
 27000 -34.1 -29.4  285  33 17   7.8   4.3 | -33.9 -29.0  300  34 17   7.6   4.2
 26000 -31.8 -25.2  280  32 17   7.8   4.3 | -31.6 -24.9  300  33 17   7.7   4.2
 25000 -29.4 -20.9  280  31 16   7.8   4.3 | -29.3 -20.7  305  32 17   7.7   4.2
 24000 -27.1 -16.8  280  30 15   7.5   4.1 | -27.0 -16.6  305  32 16   7.6   4.1
 23000 -24.9 -12.8  280  29 15   7.5   4.1 | -24.8 -12.6  305  31 16   7.6   4.1
 22000 -22.6  -8.7  285  27 14   7.5   4.1 | -22.5  -8.5  305  30 15   7.6   4.1
 21000 -20.4  -4.7  285  26 13   6.9   3.8 | -20.3  -4.5  305  28 15   7.4   4.0
 20000 -18.3  -0.9  280  24 12   6.9   3.8 | -18.1  -0.6  305  27 14   7.4   4.1
 19500 -17.3   0.9  280  23 12   7.0   3.8 | -17.0   1.4  305  26 14   7.4   4.1
 19000 -16.2   2.8  280  22 12   7.0   3.8 | -15.9   3.4  305  26 13   7.4   4.1
 18500 -15.2   4.6  280  22 11   6.9   3.8 | -14.8   5.4  305  25 13   7.0   3.9
 18000 -14.2   6.4  280  21 11   6.9   3.8 | -13.2   8.2  305  24 12   7.1   3.9
 17500 -13.1   8.4  280  20 10   6.8   3.7 | -12.1  10.2  305  23 12   6.9   3.8
 17000 -11.6  11.1  280  19 10   6.8   3.7 | -11.1  12.0  305  23 12   6.9   3.8
 16500 -10.6  12.9  275  18  9   6.8   3.7 | -10.0  14.0  305  22 11   6.8   3.8
 16000  -9.6  14.7  275  17  9   6.8   3.7 |  -9.0  15.8  305  21 11   6.8   3.7
 15500  -8.5  16.7  275  16  8   6.8   3.7 |  -8.0  17.6  305  21 11   6.7   3.7
 15000  -7.5  18.5  275  15  8   6.6   3.6 |  -7.0  19.4  305  20 10   6.5   3.6
 14500  -6.6  20.1  275  15  7   6.6   3.6 |  -6.0  21.2  305  19 10   6.6   3.6
 14000  -5.6  21.9  275  14  7   6.4   3.5 |  -5.1  22.8  310  18 10   6.2   3.4
 13500  -4.6  23.7  275  13  7   6.5   3.6 |  -4.2  24.4  310  18  9   6.2   3.4
 13000  -3.7  25.3  275  12  6   6.0   3.3 |  -3.2  26.2  310  17  9   6.1   3.4
 12500  -2.8  27.0  275  11  6   6.1   3.3 |  -2.3  27.9  315  16  8   6.1   3.4
 12000  -2.0  28.4  275  10  5   5.6   3.1 |  -1.4  29.5  315  15  8   6.1   3.4
 11500  -1.2  29.8  270   9  5   5.6   3.1 |  -0.5  31.1  315  13  7   6.2   3.4
 11000  -0.4  31.3  265   8  4   4.6   2.5 |   0.4  32.7  315  11  6   5.6   3.1
 10500   0.3  32.5  260   7  4   4.4   2.4 |   1.2  34.2  310   8  4   5.3   2.9
 10250   0.6  33.1  255   7  4   5.0   2.8 |   1.6  34.9  300   7  3   6.4   3.5
 10000   0.9  33.6  255   7  3   3.7   2.0 |   2.1  35.8  325   9  4   5.5   3.0
  9750   1.1  34.0  250   6  3   1.4   0.8 |   2.4  36.3  255   5  2   3.7   2.0
  9500   1.2  34.2  245   6  3   1.6   0.9 |   2.7  36.9  205  11  5   4.4   2.4
  9250   1.3  34.3  235   6  3   1.0   0.6 |   3.0  37.4  190  19 10   3.3   1.8
  9000   1.3  34.3  230   6  3   0.4   0.2 |   3.2  37.8  185  32 17   2.4   1.3
  8750   1.3  34.3  220   6  3   0.0   0.0 |   3.3  37.9  185  44 22   2.7   1.5
  8500   1.3  34.3  210   5  3  -0.4  -0.2 |   3.5  38.3  180  52 27   2.7   1.5
  8250   1.2  34.2  195   5  3  -0.9  -0.5 |   3.7  38.7  180  59 30   1.6   0.9
  8000   1.1  34.0  185   5  3  -1.5  -0.8 |   3.7  38.7  180  61 31   0.8   0.4
  7750   1.0  33.8  175   5  3  -0.1  -0.0 |   3.8  38.8  180  62 32   1.1   0.6
  7500   1.0  33.8  170   5  3   1.4   0.8 |   3.9  39.0  180  60 31   1.3   0.7
  7250   1.1  34.0  160   6  3   1.4   0.8 |   4.0  39.2  180  53 27   1.9   1.1
  7000   1.2  34.2  155   6  3   1.3   0.7 |   4.1  39.4  175  44 23   1.2   0.7
  6750   1.3  34.3  145   7  4   1.9   1.0 |   4.2  39.6  175  36 19   4.4   2.4
  6500   1.5  34.7  145   7  3   3.1   1.7 |   4.7  40.5  175  38 20   9.0   4.9
  6250   1.8  35.2  145   6  3   4.0   2.2 |   5.4  41.7  175  35 18   9.5   5.2
  6000   2.1  35.8  150   6  3   2.4   1.3 |   6.1  43.0  175  31 16   8.4   4.6
  5750   2.1  35.8  150   6  3  -2.5  -1.4 |   6.8  44.2  175  27 14  12.3   6.7
  5500   1.7  35.1  150   5  2  -5.7  -3.1 |   8.1  46.6  175  27 14  21.6  11.9

           11/15/2017 at 1400 MST          |       11/15/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +6.2        | CAPE...     0.0    LI...       +4.8
CINH...    -0.2    K Index...  -2.1        | CINH...    -0.2    K Index...  +4.4
                                           |
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 -65.1 -85.2  295  54 28   1.4   0.7 | -65.4 -85.7  295  52 27   1.9   1.0
 45000 -63.0 -81.4  295  60 31   1.5   0.8 | -62.5 -80.5  295  58 30   1.9   1.0
 40000 -60.8 -77.4  300  53 27   1.5   0.8 | -59.7 -75.5  300  51 26   1.9   1.0
 38000 -58.1 -72.6  300  48 25   5.9   3.2 | -57.1 -70.8  300  47 24   5.4   3.0
 36000 -54.5 -66.1  295  43 22   5.9   3.2 | -53.9 -65.0  300  43 22   5.4   3.0
 34000 -50.6 -59.1  295  39 20   7.6   4.2 | -50.2 -58.4  295  39 20   7.6   4.2
 32000 -45.5 -49.9  290  34 17   7.7   4.2 | -45.1 -49.2  295  35 18   7.6   4.2
 30000 -40.7 -41.3  285  31 16   8.3   4.5 | -40.5 -40.9  295  32 16   7.8   4.3
 29000 -38.3 -36.9  290  30 15   8.3   4.5 | -38.1 -36.6  295  30 16   7.8   4.3
 28000 -35.8 -32.4  290  29 15   8.3   4.5 | -35.8 -32.4  295  29 15   7.8   4.3
 27000 -33.4 -28.1  290  28 15   7.8   4.3 | -33.5 -28.3  295  28 14   7.9   4.3
 26000 -31.0 -23.8  295  27 14   7.8   4.3 | -31.1 -24.0  295  27 14   7.9   4.3
 25000 -28.7 -19.7  295  27 14   7.8   4.3 | -28.8 -19.8  295  27 14   7.9   4.3
 24000 -26.4 -15.5  295  26 14   7.4   4.1 | -26.5 -15.7  295  26 13   7.5   4.1
 23000 -24.2 -11.6  300  26 13   7.4   4.1 | -24.3 -11.7  295  25 13   7.4   4.1
 22000 -22.0  -7.6  300  26 13   7.4   4.1 | -22.1  -7.8  295  25 13   7.4   4.1
 21000 -19.8  -3.6  300  25 13   7.4   4.0 | -19.9  -3.8  295  24 12   6.8   3.7
 20000 -17.6   0.3  300  25 13   7.4   4.0 | -17.9  -0.2  295  23 12   6.9   3.8
 19500 -16.5   2.3  305  25 13   7.4   4.0 | -16.9   1.6  290  23 12   6.9   3.8
 19000 -15.4   4.3  305  25 13   7.4   4.1 | -15.8   3.6  290  23 12   6.9   3.8
 18500 -14.3   6.3  305  25 13   7.2   3.9 | -14.8   5.4  290  22 11   6.7   3.6
 18000 -13.3   8.1  305  25 13   7.2   3.9 | -13.3   8.1  285  22 11   6.6   3.6
 17500 -11.7  10.9  305  25 13   6.9   3.8 | -12.3   9.9  285  21 11   6.9   3.8
 17000 -10.6  12.9  300  24 12   6.9   3.8 | -11.3  11.7  285  21 11   6.9   3.8
 16500  -9.6  14.7  300  24 12   6.6   3.6 | -10.3  13.5  280  20 10   7.1   3.9
 16000  -8.6  16.5  300  23 12   6.3   3.4 |  -9.2  15.4  280  19 10   7.3   4.0
 15500  -7.7  18.1  300  22 11   6.2   3.4 |  -8.1  17.4  275  18  9   7.3   4.0
 15000  -6.8  19.8  295  20 10   5.8   3.2 |  -7.0  19.4  270  18  9   7.2   3.9
 14500  -5.9  21.4  295  19 10   5.8   3.2 |  -5.9  21.4  265  17  9   7.2   3.9
 14000  -5.0  23.0  290  17  9   6.1   3.4 |  -4.8  23.4  260  16  8   7.5   4.1
 13500  -4.1  24.6  285  15  8   6.0   3.3 |  -3.7  25.3  255  15  8   7.5   4.1
 13000  -3.2  26.2  275  13  7   6.8   3.7 |  -2.6  27.3  250  15  8   7.5   4.1
 12500  -2.2  28.0  265  12  6   6.9   3.8 |  -1.5  29.3  240  14  7   7.5   4.1
 12000  -1.2  29.8  250  11  5   7.1   3.9 |  -0.4  31.3  235  14  7   7.2   4.0
 11500  -0.1  31.8  230  11  6   7.1   3.9 |   0.7  33.3  220  14  7   7.1   3.9
 11000   1.0  33.8  210  13  7   7.0   3.9 |   1.8  35.2  210  15  8   7.3   4.0
 10500   2.0  35.6  195  18  9   7.0   3.8 |   2.8  37.0  200  20 10   7.4   4.1
 10250   2.5  36.5  195  21 11   7.3   4.0 |   3.4  38.1  195  22 11   7.0   3.8
 10000   3.1  37.6  185  30 15   6.8   3.7 |   3.9  39.0  190  25 13   6.6   3.6
  9750   3.6  38.5  185  35 18   6.1   3.3 |   4.4  39.9  190  30 16   6.7   3.7
  9500   4.0  39.2  185  40 21   6.4   3.5 |   4.9  40.8  185  35 18   6.7   3.7
  9250   4.5  40.1  185  45 23   5.8   3.2 |   5.4  41.7  185  41 21   6.6   3.6
  9000   4.9  40.8  180  58 30   5.3   2.9 |   5.9  42.6  180  55 28   5.9   3.2
  8750   5.3  41.5  180  63 32   5.4   3.0 |   6.3  43.3  180  60 31   5.2   2.8
  8500   5.7  42.3  180  64 33   5.9   3.2 |   6.6  43.9  180  60 31   5.5   3.0
  8250   6.1  43.0  180  64 33   3.9   2.1 |   7.0  44.6  180  61 31   4.2   2.3
  8000   6.3  43.3  180  58 30   2.4   1.3 |   7.3  45.1  180  59 31   3.0   1.7
  7750   6.5  43.7  180  53 28   3.8   2.1 |   7.5  45.5  180  59 31   3.8   2.1
  7500   6.8  44.2  180  53 28   4.5   2.5 |   7.8  46.0  180  62 32   4.0   2.2
  7250   7.1  44.8  180  46 24   5.2   2.8 |   8.1  46.6  180  54 28   3.7   2.1
  7000   7.5  45.5  175  31 16   5.3   2.9 |   8.3  46.9  180  30 15   3.6   2.0
  6750   7.9  46.2  175  19 10   7.3   4.0 |   8.6  47.5  180  13  7   4.2   2.3
  6500   8.6  47.5  175  33 17   9.7   5.3 |   9.0  48.2  180  56 29   5.7   3.1
  6250   9.3  48.7  175  20 10   9.9   5.5 |   9.4  48.9  175   7  4   6.3   3.4
  6000  10.1  50.2  165   7  4   9.5   5.2 |   9.9  49.8  360  55 28   7.2   3.9
  5750  10.8  51.4  020   6  3  11.1   6.1 |  10.4  50.7  360 116 60   3.6   2.0
  5500  11.8  53.2  170  12  6  15.9   8.7 |  10.2  50.4  360  41 21  -7.5  -4.1
________________________________________________________________________________

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.

CINH (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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