Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 140012
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1711 MST Wednesday, November 13, 2019

This forecast is for Thursday, November 14, 2019:

If the trigger temperature of 48.4 F/9.1 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 647 ft/min (3.3 m/s)
   Maximum height of thermals.................. 13429 ft MSL (8070 ft AGL)

Forecast maximum temperature................... 56.0 F/13.8 C
Time of trigger temperature.................... 1100 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10625 ft MSL (5266 ft AGL)
Thermal soaring outlook for Friday 11/15....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 17179 ft MSL (11820 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 39343 ft MSL (33984 ft AGL)
Wave soaring outlook for Friday 11/15.......... Poor

Remarks... None

Sunrise/Sunset.................... 06:43:01 / 16:44:44 MST
Total possible sunshine........... 10 hr 1 min 43 sec (601 min 43 sec)
Altitude of sun at 11:43:52 MST... 31.82 degrees

Upper air data from numerical model forecast valid on 11/14/2019 at 0500 MST

Freezing level.................. 5551 ft MSL (192 ft AGL)
Additional freezing level....... 7257 ft MSL (1898 ft AGL)
Convective condensation level... 11170 ft MSL (5811 ft AGL)
Lifted condensation level....... 12372 ft MSL (7013 ft AGL)
Lifted index.................... +9.7
K index......................... -9.4

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  -63.0 -81.4   315   21   11   1.2   0.6      M     M       M      M    M
 45000  -61.3 -78.3   320   22   12   0.5   0.3      M     M       M      M    M
 40000  -60.5 -76.9   325   38   20   0.5   0.3      M     M       M      M    M
 38000  -57.5 -71.5   325   41   21   7.3   4.0      M     M       M      M    M
 36000  -52.6 -62.7   330   41   21   7.3   4.0      M     M       M      M    M
 34000  -48.1 -54.6   335   41   21   7.9   4.3      M     M       M      M    M
 32000  -43.4 -46.1   335   41   21   7.9   4.3      M     M       M      M    M
 30000  -38.5 -37.3   335   40   21   8.3   4.6   38.7 101.6    19.1      M    M
 29000  -36.0 -32.8   340   40   21   8.3   4.6   38.0 100.5    18.8      M    M
 28000  -33.5 -28.3   340   40   20   8.3   4.6   37.5  99.6    18.7      M    M
 27000  -31.1 -24.0   340   39   20   7.2   3.9   37.0  98.6    18.5      M    M
 26000  -29.0 -20.2   340   39   20   7.2   4.0   35.9  96.6    17.8      M    M
 25000  -26.8 -16.2   340   38   20   7.2   4.0   35.0  94.9    17.3      M    M
 24000  -24.6 -12.3   340   37   19   6.5   3.6   34.1  93.5    16.8      M    M
 23000  -22.9  -9.2   340   36   19   5.8   3.2   32.6  90.6    15.7      M    M
 22000  -21.2  -6.2   340   35   18   5.8   3.2   31.1  88.0    14.7      M    M
 21000  -19.4  -2.9   335   33   17   6.0   3.3   29.8  85.6    13.8      M    M
 20000  -17.2   1.0   335   30   15   6.0   3.3   28.1  82.5    12.5      M    M
 19500  -16.2   2.8   335   29   15   6.0   3.3   27.4  81.4    12.0      M    M
 19000  -15.3   4.5   340   27   14   6.5   3.5   26.8  80.3    11.6      M    M
 18500  -14.7   5.5   335   26   13   2.1   1.2   25.9  78.6    10.8      M    M
 18000  -14.3   6.3   335   24   13   2.5   1.4   24.6  76.3     9.8      M    M
 17500  -13.9   7.0   335   23   12   2.0   1.1   23.4  74.1     8.8      M    M
 17000  -13.7   7.3   335   22   11   1.7   0.9   22.0  71.6     7.6      M    M
 16500  -13.5   7.7   330   20   10   1.7   0.9   20.6  69.1     6.4      M    M
 16000  -13.2   8.2   330   19   10   2.4   1.3   19.3  66.8     5.3      M    M
 15500  -12.8   9.0   325   18    9   2.4   1.3   18.1  64.6     4.2      M    M
 15000  -12.5   9.5   325   17    9   2.8   1.5   16.9  62.4     3.1      M    M
 14500  -12.1  10.2   325   15    8   2.8   1.5   15.7  60.3     2.1      M    M
 14000  -11.6  11.1   325   14    7   3.7   2.0   14.6  58.3     1.0      M    M
 13500  -11.1  12.0   320   12    6   3.9   2.1   13.7  56.6     0.1      M    M
 13000  -10.5  13.1   320   11    6   5.3   2.9   12.8  55.0    -0.8    618  3.1
 12500   -9.7  14.5   320   10    5   5.7   3.1   12.1  53.8    -1.4    578  2.9
 12000   -8.8  16.2   325    9    4   7.0   3.8   11.5  52.8    -2.0    538  2.7
 11500   -7.7  18.1   325    8    4   7.4   4.1   11.2  52.1    -2.4    490  2.5
 11000   -6.6  20.1   325    7    4   8.0   4.4   10.8  51.5    -2.8    442  2.2
 10500   -5.4  22.3   330    7    3   8.6   4.7   10.6  51.0    -3.1    391  2.0
 10250   -4.8  23.4   330    7    3   6.7   3.7   10.4  50.8    -3.2    366  1.9
 10000   -4.4  24.1   330    6    3   5.3   2.9   10.1  50.2    -3.5    347  1.8
  9750   -4.0  24.8   330    6    3   7.4   4.1    9.8  49.7    -3.8    325  1.7
  9500   -3.4  25.9   330    6    3   9.0   4.9    9.7  49.5    -3.9    300  1.5
  9250   -2.8  27.0   330    6    3   6.2   3.4    9.6  49.3    -4.1    275  1.4
  9000   -2.5  27.5   325    5    3   3.4   1.9    9.2  48.5    -4.5    258  1.3
  8750   -2.1  28.2   325    5    2   5.3   2.9    8.7  47.7    -5.0    242  1.2
  8500   -1.7  28.9   320    4    2   6.0   3.3    8.4  47.2    -5.3    222  1.1
  8250   -1.3  29.7   315    3    2   4.7   2.6    8.1  46.6    -5.6    203  1.0
  8000   -1.0  30.2   310    3    1   4.1   2.3    7.7  45.8    -6.1    186  0.9
  7750   -0.7  30.7   305    2    1   4.4   2.4    7.2  45.0    -6.5    169  0.9
  7500   -0.4  31.3   290    2    1   4.4   2.4    6.8  44.3    -6.9    152  0.8
  7250   -0.1  31.8   280    2    1   4.2   2.3    6.4  43.5    -7.4    136  0.7
  7000    0.2  32.4   260    1    1   4.3   2.3    6.0  42.8    -7.8    119  0.6
  6750    0.5  32.9   240    1    1   4.1   2.2    5.6  42.0    -8.3    102  0.5
  6500    0.8  33.4   225    1    1   3.7   2.0    5.1  41.2    -8.7     87  0.4
  6250    1.1  34.0   210    1    0   3.8   2.1    4.7  40.4    -9.2     71  0.4
  6000    1.3  34.3   185    1    0   3.1   1.7    4.2  39.6    -9.7     56  0.3
  5750    1.3  34.3   180    1    0  -6.9  -3.8    3.4  38.2   -10.5     50  0.3
  5500    0.2  32.4   180    1    0 -20.6 -11.3    1.6  34.9   -12.4     75  0.4

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

           11/14/2019 at 0800 MST          |       11/14/2019 at 1100 MST
                                           |
CAPE...     0.0    LI...      +11.3        | CAPE...     0.0    LI...      +12.5
CINH...    -0.1    K Index... -26.2        | CINH...    -0.1    K Index... -31.5
                                           |
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 -64.3 -83.7  320  21 11   0.7   0.4 | -64.1 -83.4  315  17  9   0.5   0.3
 45000 -63.2 -81.8  325  24 12   1.3   0.7 | -63.3 -81.9  315  19 10   1.1   0.6
 40000 -61.4 -78.5  325  30 16   1.3   0.7 | -61.6 -78.9  315  23 12   1.0   0.5
 38000 -57.5 -71.5  325  31 16   7.4   4.1 | -58.0 -72.4  315  23 12   7.5   4.1
 36000 -53.1 -63.6  330  31 16   7.4   4.1 | -53.5 -64.3  315  23 12   7.5   4.1
 34000 -48.4 -55.1  335  31 16   8.2   4.5 | -48.7 -55.7  320  22 11   8.4   4.6
 32000 -43.4 -46.1  335  31 16   8.2   4.5 | -43.7 -46.7  325  22 11   8.4   4.6
 30000 -38.6 -37.5  335  30 15   7.7   4.2 | -38.3 -36.9  330  21 11   7.7   4.2
 29000 -36.3 -33.3  340  29 15   7.7   4.2 | -36.0 -32.8  335  21 11   7.7   4.2
 28000 -34.0 -29.2  340  29 15   7.7   4.2 | -33.7 -28.7  335  20 10   7.7   4.2
 27000 -31.7 -25.1  340  28 14   8.5   4.7 | -31.4 -24.5  335  20 10   7.9   4.3
 26000 -29.1 -20.4  340  27 14   8.5   4.6 | -29.0 -20.2  335  19 10   7.9   4.3
 25000 -26.6 -15.9  345  26 14   8.5   4.6 | -26.7 -16.1  340  18  9   7.9   4.3
 24000 -24.1 -11.4  345  26 13   7.3   4.0 | -24.3 -11.7  340  18  9   7.9   4.3
 23000 -22.0  -7.6  345  25 13   7.0   3.8 | -21.9  -7.4  340  18  9   7.9   4.3
 22000 -19.9  -3.8  345  25 13   7.0   3.8 | -19.6  -3.3  340  17  9   7.9   4.3
 21000 -17.9  -0.2  345  24 12   5.0   2.8 | -17.3   0.9  345  17  9   6.8   3.7
 20000 -15.9   3.4  345  23 12   5.2   2.9 | -15.3   4.5  345  17  9   6.8   3.7
 19500 -15.2   4.6  345  22 11   5.2   2.9 | -14.3   6.3  345  17  9   6.8   3.7
 19000 -14.4   6.1  345  21 11   5.2   2.9 | -13.3   8.1  345  17  9   7.0   3.8
 18500 -13.6   7.5  345  20 10   5.2   2.9 | -12.4   9.7  345  17  9   5.0   2.8
 18000 -12.8   9.0  345  19 10   5.2   2.9 | -11.6  11.1  345  16  8   5.2   2.8
 17500 -12.0  10.4  345  18  9   4.8   2.6 | -10.5  13.1  340  15  8   4.4   2.4
 17000 -11.3  11.7  345  17  9   4.6   2.6 |  -9.8  14.4  340  14  7   4.5   2.5
 16500 -10.6  12.9  345  16  8   4.1   2.2 |  -9.1  15.6  340  13  7   4.2   2.3
 16000 -10.2  13.6  340  16  8   2.7   1.5 |  -8.5  16.7  340  12  6   4.0   2.2
 15500  -9.8  14.4  340  15  8   2.7   1.5 |  -7.9  17.8  335  11  6   3.7   2.0
 15000  -9.5  14.9  340  14  7   1.7   0.9 |  -7.5  18.5  335  10  5   2.6   1.4
 14500  -9.2  15.4  335  13  7   1.8   1.0 |  -7.1  19.2  335  10  5   2.6   1.5
 14000  -9.0  15.8  335  12  6   2.0   1.1 |  -6.7  19.9  330   9  5   2.2   1.2
 13500  -8.7  16.3  330  11  6   2.0   1.1 |  -6.4  20.5  330   8  4   2.2   1.2
 13000  -8.4  16.9  330  10  5   2.6   1.4 |  -6.1  21.0  325   8  4   2.7   1.5
 12500  -8.0  17.6  325   9  5   2.7   1.5 |  -5.7  21.7  320   7  4   2.6   1.4
 12000  -7.6  18.3  320   8  4   3.9   2.2 |  -5.2  22.6  310   6  3   3.8   2.1
 11500  -7.0  19.4  320   6  3   4.1   2.3 |  -4.7  23.5  305   6  3   3.9   2.1
 11000  -6.3  20.7  320   5  3   6.0   3.3 |  -4.1  24.6  290   5  3   4.2   2.3
 10500  -5.4  22.3  325   5  2   6.5   3.5 |  -3.6  25.5  280   5  2   4.6   2.5
 10250  -5.0  23.0  330   4  2   5.3   2.9 |  -3.3  26.1  270   5  2   2.8   1.5
 10000  -4.6  23.7  330   4  2   5.6   3.1 |  -3.1  26.4  270   4  2   3.7   2.0
  9750  -4.1  24.6  335   4  2   8.5   4.7 |  -2.7  27.1  260   4  2   6.9   3.8
  9500  -3.4  25.9  340   4  2   9.5   5.2 |  -2.2  28.0  250   3  2   6.7   3.7
  9250  -2.8  27.0  345   4  2   7.4   4.0 |  -1.8  28.8  240   3  2   5.4   3.0
  9000  -2.3  27.9  345   3  2   5.7   3.2 |  -1.4  29.5  230   3  1   5.1   2.8
  8750  -1.8  28.8  345   3  2   8.6   4.7 |  -0.9  30.4  220   2  1   8.0   4.4
  8500  -1.1  30.0  345   3  1   9.4   5.1 |  -0.3  31.5  205   2  1   8.3   4.6
  8250  -0.5  31.1  340   2  1   7.1   3.9 |   0.2  32.4  190   2  1   6.7   3.7
  8000  -0.1  31.8  330   2  1   6.3   3.5 |   0.7  33.3  180   2  1   6.3   3.4
  7750   0.4  32.7  320   2  1   7.1   3.9 |   1.2  34.2  175   2  1   8.9   4.9
  7500   0.9  33.6  295   2  1   5.2   2.8 |   1.9  35.4  170   2  1   8.5   4.7
  7250   1.2  34.2  290   2  1   3.2   1.7 |   2.4  36.3  170   2  1   6.5   3.5
  7000   1.4  34.5  280   2  1   3.9   2.2 |   2.9  37.2  170   2  1   6.2   3.4
  6750   1.7  35.1  270   2  1   2.9   1.6 |   3.4  38.1  170   2  1   9.4   5.1
  6500   1.8  35.2  260   2  1   1.0   0.5 |   4.2  39.6  170   2  1  10.3   5.7
  6250   1.9  35.4  255   2  1   1.3   0.7 |   4.8  40.6  170   2  1   8.1   4.4
  6000   1.9  35.4  250   2  1  -1.1  -0.6 |   5.4  41.7  170   2  1   7.5   4.1
  5750   1.5  34.7  245   2  1  -9.1  -5.0 |   6.0  42.8  170   2  1  10.9   6.0
  5500   0.6  33.1  225   1  1 -14.5  -7.9 |   7.2  45.0  170   2  1  21.0  11.5

           11/14/2019 at 1400 MST          |       11/14/2019 at 1700 MST
                                           |
CAPE...     0.0    LI...      +11.0        | CAPE...     0.0    LI...       +9.8
CINH...     0.0    K Index... -35.8        | CINH...    -0.0    K Index... -23.9
                                           |
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 -64.4 -83.9  300  15  8   0.7   0.4 | -64.4 -83.9  295  15  8   1.3   0.7
 45000 -63.2 -81.8  300  18  9   1.2   0.7 | -62.3 -80.1  295  17  9   0.6   0.3
 40000 -61.4 -78.5  300  21 11   1.2   0.6 | -61.4 -78.5  290  18  9   0.6   0.3
 38000 -58.0 -72.4  300  21 11   7.0   3.8 | -58.2 -72.8  295  18  9   6.9   3.8
 36000 -53.8 -64.8  300  20 10   7.0   3.8 | -54.0 -65.2  295  18  9   6.9   3.8
 34000 -49.3 -56.7  305  19 10   8.3   4.5 | -49.5 -57.1  300  17  9   8.2   4.5
 32000 -44.3 -47.7  305  17  9   8.3   4.5 | -44.0 -47.2  300  16  8   8.2   4.5
 30000 -38.8 -37.8  315  16  8   8.0   4.4 | -39.1 -38.4  300  16  8   8.3   4.6
 29000 -36.4 -33.5  315  15  8   8.0   4.4 | -36.6 -33.9  300  15  8   8.3   4.6
 28000 -34.0 -29.2  320  15  8   8.0   4.4 | -34.1 -29.4  300  15  8   8.3   4.6
 27000 -31.6 -24.9  320  15  8   8.1   4.5 | -31.7 -25.1  300  14  7   7.9   4.3
 26000 -29.2 -20.6  320  15  8   8.1   4.5 | -29.4 -20.9  300  14  7   7.9   4.3
 25000 -26.8 -16.2  320  15  8   8.1   4.5 | -27.0 -16.6  300  14  7   7.9   4.3
 24000 -24.4 -11.9  320  15  8   7.7   4.2 | -24.7 -12.5  300  13  7   7.8   4.3
 23000 -22.0  -7.6  320  15  8   7.7   4.2 | -22.3  -8.1  300  13  6   7.8   4.3
 22000 -19.7  -3.5  320  15  8   7.7   4.2 | -20.0  -4.0  300  12  6   7.8   4.3
 21000 -17.4   0.7  325  14  7   7.9   4.3 | -17.5   0.5  305  12  6   8.4   4.6
 20000 -15.1   4.8  330  13  7   7.9   4.3 | -15.0   5.0  305  11  6   8.4   4.6
 19500 -13.9   7.0  330  13  7   7.9   4.3 | -13.1   8.4  305  11  6   8.4   4.6
 19000 -12.7   9.1  330  12  6   8.0   4.4 | -11.8  10.8  305  11  5   7.9   4.4
 18500 -11.6  11.1  335  12  6   6.9   3.8 | -10.7  12.7  305  10  5   7.6   4.2
 18000 -10.0  14.0  330  11  6   7.1   3.9 |  -9.5  14.9  305  10  5   7.6   4.2
 17500  -9.0  15.8  330  11  5   6.1   3.3 |  -8.5  16.7  305  10  5   6.3   3.5
 17000  -8.1  17.4  330  10  5   6.2   3.4 |  -7.5  18.5  310  10  5   6.4   3.5
 16500  -7.2  19.0  325  10  5   5.4   3.0 |  -6.6  20.1  310  10  5   5.5   3.0
 16000  -6.4  20.5  325  10  5   4.9   2.7 |  -5.8  21.6  310  10  5   5.0   2.8
 15500  -5.7  21.7  320   9  5   4.5   2.5 |  -5.1  22.8  310  10  5   4.7   2.6
 15000  -5.2  22.6  315   9  5   2.8   1.5 |  -4.5  23.9  310  10  5   3.8   2.1
 14500  -4.8  23.4  310   9  4   2.9   1.6 |  -3.9  25.0  310  10  5   3.9   2.1
 14000  -4.4  24.1  310   8  4   2.1   1.2 |  -3.4  25.9  310  11  5   3.9   2.1
 13500  -4.1  24.6  305   8  4   2.1   1.2 |  -2.8  27.0  305  11  5   3.8   2.1
 13000  -3.7  25.3  300   8  4   3.4   1.8 |  -2.1  28.2  305  11  5   5.1   2.8
 12500  -3.2  26.2  295   8  4   3.3   1.8 |  -1.4  29.5  305  11  5   5.1   2.8
 12000  -2.7  27.1  290   8  4   4.6   2.5 |  -0.7  30.7  300  10  5   4.8   2.6
 11500  -2.0  28.4  285   8  4   4.7   2.6 |  -0.0  32.0  295  10  5   4.9   2.7
 11000  -1.3  29.7  280   8  4   5.2   2.9 |   0.6  33.1  290  10  5   4.0   2.2
 10500  -0.6  30.9  275   7  4   5.8   3.2 |   1.2  34.2  280   9  5   4.4   2.4
 10250  -0.2  31.6  270   7  4   3.8   2.1 |   1.5  34.7  275   8  4   2.8   1.5
 10000  -0.0  32.0  270   7  3   3.5   1.9 |   1.6  34.9  270   8  4   3.5   1.9
  9750   0.3  32.5  260   6  3   5.2   2.8 |   2.0  35.6  265   7  4   5.4   3.0
  9500   0.7  33.3  250   5  3   5.2   2.8 |   2.3  36.1  260   6  3   5.6   3.1
  9250   1.0  33.8  240   5  3   3.5   1.9 |   2.7  36.9  250   6  3   3.1   1.7
  9000   1.2  34.2  225   5  2   2.9   1.6 |   2.8  37.0  240   5  3   2.4   1.3
  8750   1.5  34.7  210   4  2   5.6   3.1 |   3.1  37.6  235   4  2   5.9   3.2
  8500   1.9  35.4  190   4  2   6.2   3.4 |   3.5  38.3  220   4  2   6.5   3.6
  8250   2.4  36.3  175   4  2   6.7   3.7 |   4.0  39.2  210   3  2   6.7   3.7
  8000   2.9  37.2  170   4  2   7.2   3.9 |   4.5  40.1  200   3  2   7.0   3.9
  7750   3.4  38.1  160   4  2   7.5   4.1 |   5.0  41.0  190   3  1   6.1   3.4
  7500   4.0  39.2  155   4  2   9.0   4.9 |   5.4  41.7  180   3  1   6.6   3.6
  7250   4.7  40.5  155   4  2  10.1   5.5 |   6.0  42.8  175   3  2   7.8   4.3
  7000   5.4  41.7  150   4  2  10.1   5.6 |   6.6  43.9  170   3  2   8.4   4.6
  6750   6.2  43.2  150   4  2   9.5   5.2 |   7.1  44.8  170   3  2   5.0   2.7
  6500   6.9  44.4  150   4  2   9.6   5.3 |   7.4  45.3  165   4  2   4.8   2.6
  6250   7.6  45.7  150   4  2  10.4   5.7 |   7.9  46.2  160   3  2   7.3   4.0
  6000   8.4  47.1  150   4  2   9.7   5.3 |   8.4  47.1  155   3  2   7.9   4.3
  5750   9.2  48.6  145   4  2  11.8   6.5 |   8.9  48.0  150   3  2   3.0   1.7
  5500  10.2  50.4  145   3  2  17.2   9.4 |   8.6  47.5  140   3  1  -9.6  -5.3
________________________________________________________________________________

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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