Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 061214
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0514 MST Wednesday, December 6, 2017

This forecast is for Wednesday, December 6, 2017:

If the trigger temperature of 37.9 F/3.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7922 ft MSL (2622 ft AGL)

Forecast maximum temperature................... 36.0 F/2.7 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1400 MST
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5779 ft MSL (479 ft AGL)
Thermal soaring outlook for Thursday 12/07..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 15862 ft MSL (10562 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 44357 ft MSL (39057 ft AGL)
Wave soaring outlook for Thursday 12/07........ Poor

Remarks... None

Sunrise/Sunset.................... 07:06:43 / 16:34:45 MST
Total possible sunshine........... 9 hr 28 min 2 sec (568 min 2 sec)
Altitude of sun at 11:50:44 MST... 27.62 degrees

Upper air data from numerical model forecast valid on 12/06/2017 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 12720 ft MSL (7420 ft AGL)
Lifted condensation level....... 11589 ft MSL (6289 ft AGL)
Lifted index.................... +13.3
K index......................... +5.7

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  -57.4 -71.3   290   21   11   1.1   0.6      M     M       M      M    M
 45000  -55.8 -68.4   300   29   15   1.0   0.6      M     M       M      M    M
 40000  -57.7 -71.9   295   35   18  -1.5  -0.8      M     M       M      M    M
 38000  -57.9 -72.2   290   36   19   2.1   1.2      M     M       M      M    M
 36000  -56.6 -69.9   295   37   19   2.2   1.2      M     M       M      M    M
 34000  -55.3 -67.5   295   37   19   2.9   1.6      M     M       M      M    M
 32000  -51.7 -61.1   295   38   20   6.3   3.5      M     M       M      M    M
 30000  -47.9 -54.2   295   39   20   6.5   3.6      M     M       M      M    M
 29000  -45.3 -49.5   295   38   20   6.8   3.8   28.3  83.0    19.7      M    M
 28000  -43.3 -45.9   295   38   19   6.8   3.8   27.2  80.9    19.1      M    M
 27000  -41.2 -42.2   300   37   19   6.8   3.7   26.2  79.1    18.6      M    M
 26000  -39.1 -38.4   300   37   19   7.3   4.0   25.1  77.2    18.0      M    M
 25000  -36.9 -34.4   295   36   19   7.3   4.0   24.2  75.5    17.4      M    M
 24000  -34.7 -30.5   295   36   18   7.3   4.0   23.3  74.0    17.0      M    M
 23000  -32.8 -27.0   295   35   18   6.3   3.5   22.1  71.8    16.2      M    M
 22000  -30.9 -23.6   295   34   17   6.3   3.5   20.9  69.5    15.4      M    M
 21000  -29.0 -20.2   300   32   17   6.2   3.4   19.7  67.5    14.6      M    M
 20000  -27.2 -17.0   300   31   16   5.7   3.1   18.2  64.8    13.5      M    M
 19500  -26.4 -15.5   300   30   16   5.7   3.1   17.5  63.5    13.0      M    M
 19000  -25.6 -14.1   300   29   15   5.7   3.1   16.8  62.2    12.4      M    M
 18500  -24.7 -12.5   300   29   15   5.7   3.1   16.1  61.1    11.9      M    M
 18000  -23.8 -10.8   300   28   14   6.2   3.4   15.5  59.9    11.4      M    M
 17500  -22.9  -9.2   295   26   14   6.3   3.5   14.9  58.8    10.9      M    M
 17000  -22.1  -7.8   295   25   13   4.3   2.3   14.2  57.5    10.4      M    M
 16500  -21.5  -6.7   295   24   12   3.9   2.1   13.2  55.7     9.5      M    M
 16000  -20.9  -5.6   295   22   11   3.1   1.7   12.2  53.9     8.7      M    M
 15500  -20.7  -5.3   295   20   10   2.1   1.2   10.9  51.6     7.6      M    M
 15000  -20.2  -4.4   300   17    9   2.1   1.2    9.0  48.1     5.9      M    M
 14500  -19.9  -3.8   300   15    7   2.0   1.1    7.7  45.8     4.7      M    M
 14000  -19.5  -3.1   305   13    6   5.7   3.1    6.6  43.9     3.8      M    M
 13500  -18.4  -1.1   315   11    6   7.0   3.8    6.1  43.1     3.4      M    M
 13000  -17.4   0.7   325   11    5   6.8   3.7    5.7  42.3     3.0      M    M
 12500  -16.4   2.5   330   11    6   6.6   3.6    5.2  41.3     2.5      M    M
 12000  -15.4   4.3   335   11    6   7.7   4.2    4.7  40.5     2.1      M    M
 11500  -14.2   6.4   340   11    6   8.1   4.4    4.4  40.0     1.8      M    M
 11000  -13.0   8.6   345   11    6   8.0   4.4    4.2  39.5     1.6      M    M
 10500  -11.8  10.8   345   11    6   7.9   4.3    3.9  39.0     1.3      M    M
 10250  -11.2  11.8   350   11    6   8.3   4.5    3.8  38.8     1.2      M    M
 10000  -10.6  12.9   350   11    6   8.8   4.8    3.7  38.6     1.1      M    M
  9750   -9.9  14.2   350   11    6   9.2   5.0    3.6  38.5     1.0      M    M
  9500   -9.2  15.4   350   11    6   9.5   5.2    3.6  38.4     1.0      M    M
  9250   -8.5  16.7   350   11    5   8.6   4.7    3.5  38.4     1.0      M    M
  9000   -7.9  17.8   350   10    5   7.6   4.2    3.4  38.1     0.8      M    M
  8750   -7.3  18.9   350   10    5   8.9   4.9    3.3  37.9     0.7      M    M
  8500   -6.6  20.1   345    9    5   8.1   4.5    3.2  37.8     0.7      M    M
  8250   -6.1  21.0   340    9    4   5.6   3.1    3.0  37.3     0.4      M    M
  8000   -5.7  21.7   335    8    4   4.9   2.7    2.6  36.7     0.1      M    M
  7750   -5.3  22.5   325    7    4   6.4   3.5    2.3  36.1    -0.2    132  0.7
  7500   -4.8  23.4   320    6    3   6.1   3.3    2.0  35.7    -0.4    109  0.6
  7250   -4.5  23.9   305    5    3   4.5   2.5    1.7  35.0    -0.8     91  0.5
  7000   -4.1  24.6   285    5    2   4.8   2.7    1.3  34.3    -1.2     73  0.4
  6750   -3.7  25.3   260    5    2   5.3   2.9    0.9  33.7    -1.6     55  0.3
  6500   -3.3  26.1   250    4    2   5.8   3.2    0.6  33.1    -1.9     35  0.2
  6250   -2.9  26.8   235    4    2   5.9   3.3    0.3  32.6    -2.2     14  0.1
  6000   -2.5  27.5   220    4    2   5.2   2.8    0.0  32.0    -2.5      M    M
  5750   -2.2  28.0   210    4    2   1.1   0.6   -0.5  31.2    -3.0      M    M
  5500   -2.3  27.9   210    3    1  -3.3  -1.8   -1.3  29.7    -3.8      M    M

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

           12/06/2017 at 0800 MST          |       12/06/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +8.3        | CAPE...     0.0    LI...       +5.1
CINH...     0.0    K Index...   0.0        | CINH...     0.0    K Index...  +4.5
                                           |
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 -58.0 -72.4  295  21 11   2.2   1.2 | -58.8 -73.8  290  23 12   2.2   1.2
 45000 -54.7 -66.5  295  27 14   2.2   1.2 | -55.6 -68.1  295  27 14   2.1   1.2
 40000 -54.5 -66.1  295  34 17  -0.2  -0.1 | -52.8 -63.0  290  31 16   1.8   1.0
 38000 -54.6 -66.3  290  36 19   0.4   0.2 | -51.7 -61.1  290  33 17   1.6   0.9
 36000 -54.3 -65.7  290  37 19   0.5   0.3 | -50.8 -59.4  290  34 18   1.6   0.9
 34000 -54.0 -65.2  285  38 20  -0.1  -0.1 | -49.8 -57.6  290  35 18   1.4   0.7
 32000 -51.3 -60.3  285  39 20   5.1   2.8 | -47.8 -54.0  285  38 19   3.6   2.0
 30000 -48.2 -54.8  290  41 21   5.1   2.8 | -45.7 -50.3  280  41 21   3.6   2.0
 29000 -45.9 -50.6  290  41 21   6.4   3.5 | -44.5 -48.1  280  40 21   3.8   2.1
 28000 -44.0 -47.2  290  40 21   6.4   3.5 | -43.1 -45.6  280  38 19   3.8   2.1
 27000 -42.1 -43.8  295  40 21   6.4   3.5 | -42.0 -43.6  285  36 19   3.8   2.1
 26000 -40.0 -40.0  295  39 20   7.1   3.9 | -40.7 -41.3  285  34 18   4.6   2.5
 25000 -37.9 -36.2  295  39 20   7.1   3.9 | -39.4 -38.9  290  33 17   4.6   2.5
 24000 -35.7 -32.3  295  38 20   7.1   3.9 | -38.0 -36.4  295  32 16   4.6   2.5
 23000 -33.8 -28.8  295  37 19   5.9   3.2 | -36.5 -33.7  295  30 16   5.1   2.8
 22000 -32.1 -25.8  300  35 18   5.8   3.2 | -35.0 -31.0  300  29 15   5.1   2.8
 21000 -30.3 -22.5  300  33 17   5.9   3.2 | -33.5 -28.3  300  27 14   5.0   2.8
 20000 -28.8 -19.8  300  31 16   5.0   2.8 | -32.0 -25.6  305  25 13   5.1   2.8
 19500 -28.0 -18.4  300  30 16   5.0   2.8 | -31.2 -24.2  305  25 13   5.1   2.8
 19000 -27.3 -17.1  300  29 15   5.0   2.8 | -30.5 -22.9  305  24 12   5.1   2.8
 18500 -26.5 -15.7  305  28 15   5.2   2.9 | -29.7 -21.5  305  23 12   5.3   2.9
 18000 -25.9 -14.6  305  27 14   3.4   1.9 | -29.1 -20.4  305  22 11   2.9   1.6
 17500 -25.3 -13.5  305  26 13   3.6   2.0 | -28.6 -19.5  310  21 11   3.0   1.6
 17000 -24.8 -12.6  305  25 13   2.6   1.4 | -28.2 -18.8  310  20 10   2.6   1.4
 16500 -24.5 -12.1  305  23 12   2.2   1.2 | -27.9 -18.2  315  19 10   2.5   1.4
 16000 -24.2 -11.6  305  22 11   2.5   1.4 | -27.5 -17.5  315  19 10   3.3   1.8
 15500 -23.6 -10.5  305  19 10   2.9   1.6 | -26.8 -16.2  315  18  9   5.2   2.8
 15000 -23.1  -9.6  300  17  9   4.4   2.4 | -26.1 -15.0  315  17  9   5.6   3.1
 14500 -22.4  -8.3  300  15  8   4.7   2.6 | -24.4 -11.9  315  15  8   8.3   4.6
 14000 -21.6  -6.9  295  13  7   7.8   4.3 | -23.1  -9.6  315  14  7   8.7   4.8
 13500 -20.2  -4.4  300  12  6   9.2   5.0 | -21.8  -7.2  315  13  7   8.9   4.9
 13000 -18.9  -2.0  305  10  5   7.6   4.2 | -20.5  -4.9  315  12  6   9.1   5.0
 12500 -17.9  -0.2  315  11  5   6.7   3.7 | -19.1  -2.4  320  12  6   9.2   5.1
 12000 -16.9   1.6  325  11  6   6.7   3.7 | -17.7   0.1  320  12  6   9.0   4.9
 11500 -15.9   3.4  330  12  6   6.7   3.7 | -16.4   2.5  320  12  6   8.9   4.9
 11000 -14.9   5.2  335  13  7   7.5   4.1 | -15.1   4.8  325  12  6   8.3   4.6
 10500 -13.7   7.3  340  13  7   7.8   4.3 | -13.9   7.0  325  12  6   8.5   4.6
 10250 -13.1   8.4  345  13  7   7.3   4.0 | -13.3   8.1  330  11  6   7.3   4.0
 10000 -12.6   9.3  345  13  7   6.3   3.5 | -12.8   9.0  330  12  6   5.3   2.9
  9750 -12.1  10.2  345  13  7   8.2   4.5 | -12.4   9.7  330  12  6   8.5   4.7
  9500 -11.4  11.5  350  13  7   9.7   5.3 | -11.6  11.1  335  12  6  10.6   5.8
  9250 -10.8  12.6  350  13  7   7.7   4.2 | -10.9  12.4  335  13  6   7.6   4.2
  9000 -10.3  13.5  350  13  7   6.3   3.4 | -10.4  13.3  335  13  7   5.9   3.2
  8750  -9.8  14.4  355  13  7   8.3   4.6 |  -9.9  14.2  340  13  7   8.1   4.4
  8500  -9.1  15.6  355  13  7   8.8   4.9 |  -9.2  15.4  340  13  7   8.8   4.8
  8250  -8.5  16.7  355  13  7   7.3   4.0 |  -8.7  16.3  340  12  6   7.3   4.0
  8000  -8.0  17.6  360  12  6   6.7   3.7 |  -8.1  17.4  340  11  6   7.3   4.0
  7750  -7.5  18.5  360  12  6   8.9   4.9 |  -7.6  18.3  340  11  5   8.0   4.4
  7500  -6.7  19.9  005  11  6   9.7   5.3 |  -7.0  19.4  340  10  5   8.3   4.6
  7250  -6.1  21.0  005  11  5   8.1   4.4 |  -6.4  20.5  340   9  4   7.9   4.3
  7000  -5.5  22.1  005  10  5   8.4   4.6 |  -5.8  21.6  340   8  4   7.7   4.2
  6750  -4.8  23.4  010   9  4   8.8   4.8 |  -5.2  22.6  340   7  4   8.6   4.7
  6500  -4.2  24.4  010   8  4   9.3   5.1 |  -4.5  23.9  340   7  4  10.2   5.6
  6250  -3.4  25.9  005   6  3   9.7   5.3 |  -3.7  25.3  340   7  3  10.2   5.6
  6000  -2.7  27.1  005   5  3   8.4   4.6 |  -3.0  26.6  340   6  3  10.6   5.8
  5750  -2.3  27.9  360   4  2   4.2   2.3 |  -2.1  28.2  340   6  3  13.9   7.6
  5500  -2.1  28.2  345   2  1   1.0   0.6 |  -0.9  30.4  340   5  3  18.0   9.9

           12/06/2017 at 1400 MST          |       12/06/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +4.3        | CAPE...     0.0    LI...       +3.4
CINH...     0.0    K Index...  +1.5        | CINH...     0.0    K Index...  +4.3
                                           |
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 -57.4 -71.3  290  21 11   1.3   0.7 | -57.2 -71.0  290  19 10   1.8   1.0
 45000 -55.4 -67.7  290  28 14   1.3   0.7 | -54.5 -66.1  290  24 12   1.8   1.0
 40000 -52.1 -61.8  290  31 16   2.2   1.2 | -51.3 -60.3  295  26 13   2.0   1.1
 38000 -50.8 -59.4  290  32 16   1.9   1.0 | -50.1 -58.2  295  26 13   2.0   1.1
 36000 -49.7 -57.5  285  30 15   1.9   1.0 | -48.9 -56.0  290  25 13   2.0   1.1
 34000 -48.6 -55.5  285  28 15   1.8   1.0 | -47.7 -53.9  285  24 12   2.0   1.1
 32000 -47.1 -52.8  280  30 15   2.7   1.5 | -47.0 -52.6  285  23 12   0.9   0.5
 30000 -45.4 -49.7  280  32 17   2.7   1.5 | -46.4 -51.5  285  22 11   0.9   0.5
 29000 -44.2 -47.6  285  31 16   3.6   2.0 | -45.9 -50.6  290  20 10   2.6   1.4
 28000 -43.1 -45.6  285  28 15   3.6   2.0 | -44.9 -48.8  295  16  8   2.6   1.4
 27000 -42.1 -43.8  285  26 13   3.6   2.0 | -44.1 -47.4  300  13  7   2.6   1.4
 26000 -40.9 -41.6  290  23 12   3.9   2.1 | -43.1 -45.6  310  11  6   5.4   3.0
 25000 -39.8 -39.6  295  21 11   3.9   2.1 | -41.5 -42.7  320   9  5   5.3   2.9
 24000 -38.6 -37.5  300  19 10   3.9   2.1 | -39.9 -39.8  335   8  4   5.3   2.9
 23000 -37.5 -35.5  305  17  9   3.9   2.2 | -38.3 -36.9  345   8  4   5.2   2.8
 22000 -36.3 -33.3  310  16  8   3.9   2.2 | -36.8 -34.2  345   9  5   5.2   2.9
 21000 -35.1 -31.2  315  15  8   3.9   2.1 | -35.2 -31.4  345  10  5   5.3   2.9
 20000 -33.7 -28.7  315  15  8   5.0   2.8 | -33.9 -29.0  345  11  6   4.0   2.2
 19500 -33.0 -27.4  320  15  7   5.1   2.8 | -33.3 -27.9  340  12  6   4.0   2.2
 19000 -32.2 -26.0  320  14  7   5.1   2.8 | -32.8 -27.0  340  12  6   4.0   2.2
 18500 -31.5 -24.7  320  14  7   5.1   2.8 | -32.2 -26.0  340  13  7   3.9   2.1
 18000 -30.7 -23.3  320  14  7   4.2   2.3 | -31.5 -24.7  340  13  7   5.4   3.0
 17500 -30.1 -22.2  325  15  8   4.1   2.3 | -30.7 -23.3  340  14  7   5.6   3.1
 17000 -29.5 -21.1  325  15  8   4.5   2.5 | -29.9 -21.8  340  14  7   5.4   2.9
 16500 -28.8 -19.8  325  16  8   4.9   2.7 | -29.1 -20.4  340  15  7   5.1   2.8
 16000 -28.1 -18.6  325  16  8   5.2   2.8 | -28.3 -18.9  340  15  8   5.3   2.9
 15500 -27.2 -17.0  320  17  9   6.2   3.4 | -27.5 -17.5  335  15  8   6.1   3.3
 15000 -26.3 -15.3  320  17  9   6.3   3.5 | -26.5 -15.7  335  15  8   6.1   3.4
 14500 -24.5 -12.1  320  16  8   8.9   4.9 | -25.5 -13.9  335  15  8   7.6   4.2
 14000 -23.2  -9.8  315  15  8   9.1   5.0 | -23.8 -10.8  330  15  8   8.5   4.7
 13500 -21.8  -7.2  320  14  7   9.3   5.1 | -22.5  -8.5  330  15  8   9.2   5.0
 13000 -20.4  -4.7  320  13  7   8.9   4.9 | -21.1  -6.0  330  15  7   9.3   5.1
 12500 -19.1  -2.4  320  13  7   8.7   4.8 | -19.7  -3.5  325  14  7   9.3   5.1
 12000 -17.8  -0.0  320  12  6   8.2   4.5 | -18.4  -1.1  325  14  7   8.8   4.8
 11500 -16.7   1.9  325  12  6   7.9   4.3 | -17.1   1.2  330  13  7   8.6   4.7
 11000 -15.5   4.1  325  12  6   7.8   4.3 | -15.8   3.6  330  13  7   8.4   4.6
 10500 -14.3   6.3  330  12  6   7.9   4.3 | -14.6   5.7  330  13  7   8.5   4.7
 10250 -13.7   7.3  330  12  6   7.3   4.0 | -13.9   7.0  330  13  6   8.0   4.4
 10000 -13.2   8.2  335  12  6   6.4   3.5 | -13.4   7.9  330  13  6   7.0   3.9
  9750 -12.7   9.1  335  12  6   7.2   4.0 | -12.8   9.0  330  13  6   8.7   4.8
  9500 -12.2  10.0  340  11  6   7.9   4.3 | -12.1  10.2  335  12  6  10.1   5.6
  9250 -11.6  11.1  340  10  5   8.2   4.5 | -11.4  11.5  335  12  6   7.7   4.2
  9000 -11.0  12.2  345  10  5   7.7   4.2 | -10.9  12.4  335  13  6   5.5   3.0
  8750 -10.4  13.3  345  10  5  10.2   5.6 | -10.4  13.3  340  13  7   8.6   4.7
  8500  -9.5  14.9  345  10  5  11.4   6.2 |  -9.7  14.5  340  13  7   9.8   5.4
  8250  -8.8  16.2  345   9  5   9.3   5.1 |  -9.1  15.6  345  13  7   7.6   4.1
  8000  -8.1  17.4  345   9  5   8.7   4.8 |  -8.5  16.7  345  13  7   7.2   4.0
  7750  -7.4  18.7  345   9  5  10.7   5.9 |  -8.0  17.6  350  13  7   8.3   4.6
  7500  -6.5  20.3  345   9  5  11.0   6.1 |  -7.3  18.9  350  12  6   9.3   5.1
  7250  -5.8  21.6  345   9  5   9.3   5.1 |  -6.6  20.1  350  12  6   9.0   5.0
  7000  -5.1  22.8  345   9  5   9.7   5.3 |  -5.9  21.4  350  12  6   9.0   5.0
  6750  -4.3  24.3  345   9  5   9.9   5.4 |  -5.3  22.5  355  11  6   8.9   4.9
  6500  -3.6  25.5  345   9  5  10.6   5.8 |  -4.6  23.7  355  11  6   9.4   5.2
  6250  -2.8  27.0  345   9  4  11.0   6.0 |  -3.8  25.2  355  10  5  10.0   5.5
  6000  -2.0  28.4  345   8  4   9.9   5.4 |  -3.1  26.4  355  10  5   9.5   5.2
  5750  -1.2  29.8  345   8  4  12.2   6.7 |  -2.5  27.5  355   8  4   7.7   4.2
  5500  -0.0  32.0  345   7  4  19.4  10.7 |  -2.0  28.4  355   6  3   5.6   3.1
________________________________________________________________________________

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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