Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 211338
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0638 MST Sunday, December 21, 2014

This forecast is for Sunday, December 21, 2014:

If the trigger temperature of 49.5 F/9.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 189 ft/min (1.0 m/s)
   Maximum height of thermals.................. 12882 ft MSL (7597 ft AGL)

Forecast maximum temperature................... 57.0 F/14.3 C
Time of trigger temperature.................... 1200 MST
Time of overdevelopment........................ 1600 MST
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 10712 ft MSL (5426 ft AGL)
Thermal soaring outlook for Monday 12/22....... Poor

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Becoming fair
Height of stable layer (12-18K ft MSL)......... 13885 ft MSL (8600 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 15359 ft MSL (10074 ft AGL)
Wave soaring outlook for Monday 12/22.......... Good

Remarks... Snow spilling into the foothills

Sunrise/Sunset.................... 07:17:01 / 16:38:25 MST
Total possible sunshine........... 9 hr 21 min 25 sec (561 min 25 sec)
Altitude of sun at 11:57:43 MST... 26.86 degrees

Upper air data from rawinsonde observation taken on 12/21/2014 at 0500 MST

Freezing level.................. 5509 ft MSL (224 ft AGL)
Additional freezing level....... 8374 ft MSL (3089 ft AGL)
Convective condensation level... 16930 ft MSL (11645 ft AGL)
Lifted condensation level....... 14827 ft MSL (9542 ft AGL)
Lifted index.................... +3.6
K index......................... +4.8

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  -55.7 -68.3   315   20   10   1.8   1.0  108.9 228.0    54.1      M    M
 45000  -58.2 -72.8   320   44   23   3.6   2.0   79.9 175.7    40.2      M    M
 40000  -56.3 -69.3   320   58   30   3.2   1.7   58.6 137.4    29.2      M    M
 38000  -57.8 -72.0   320   52   27   4.4   2.4   47.4 117.3    22.5      M    M
 36000  -55.4 -67.7   330   44   23   4.4   2.4   42.4 108.4    19.7      M    M
 34000  -53.1 -63.6   335   60   31   5.5   3.0   37.3  99.2    16.6      M    M
 32000  -50.8 -59.4   335   82   42   5.1   2.8   32.4  90.4    13.5      M    M
 30000  -48.7 -55.7   330   92   47   7.0   3.9   27.4  81.3    10.1      M    M
 29000  -46.4 -51.5   330   87   45   8.7   4.8   26.4  79.6     9.5      M    M
 28000  -43.2 -45.8   335   80   41   8.8   4.8   26.0  78.7     9.3      M    M
 27000  -40.5 -40.9   335   73   38   8.7   4.8   25.6  78.2     9.1      M    M
 26000  -38.1 -36.6   335   52   27   7.9   4.3   25.1  77.2     8.8      M    M
 25000  -35.7 -32.3   335   51   26   7.8   4.3   24.4  75.9     8.4      M    M
 24000  -33.4 -28.1   335   43   22   7.8   4.3   23.6  74.5     7.8      M    M
 23000  -31.0 -23.8   330   36   19   7.1   3.9   23.0  73.4     7.4      M    M
 22000  -28.8 -19.8   325   30   15   7.3   4.0   22.1  71.7     6.7      M    M
 21000  -26.4 -15.5   320   29   15   9.1   5.0   21.5  70.7     6.3      M    M
 20000  -23.7 -10.7   315   29   15   9.2   5.0   21.3  70.4     6.2      M    M
 19500  -22.3  -8.1   310   29   15   9.2   5.0   21.2  70.1     6.1      M    M
 19000  -20.9  -5.6   310   30   15   9.2   5.0   21.0  69.9     6.0      M    M
 18500  -19.6  -3.3   305   31   16   9.3   5.1   20.9  69.7     6.0      M    M
 18000  -18.3  -0.9   300   31   16   8.3   4.5   20.8  69.4     5.9      M    M
 17500  -17.1   1.2   305   32   17   8.0   4.4   20.5  68.8     5.6      M    M
 17000  -15.9   3.4   305   34   18   8.0   4.4   20.2  68.3     5.4      M    M
 16500  -14.7   5.5   305   36   18   8.1   4.4   19.9  67.8     5.1      M    M
 16000  -13.5   7.7   310   38   19   8.3   4.5   19.6  67.3     4.9      M    M
 15500  -12.5   9.5   310   40   21   5.3   2.9   19.2  66.5     4.5      M    M
 15000  -11.7  10.9   310   42   22   5.1   2.8   18.4  65.1     3.9      M    M
 14500  -11.0  12.2   310   40   21   4.9   2.7   17.6  63.7     3.2      M    M
 14000  -10.2  13.6   305   33   17  -2.2  -1.2   16.1  60.9     1.7      M    M
 13500  -10.2  13.6   305   27   14   5.8   3.2   14.4  58.0     0.3      M    M
 13000   -9.0  15.8   310   21   11   7.9   4.3   14.1  57.5     0.0      M    M
 12500   -7.8  18.0   310   14    7   8.4   4.6   13.9  57.0    -0.2    540  2.7
 12000   -7.1  19.2   320    9    5   1.4   0.7   13.1  55.5    -1.0    505  2.6
 11500   -6.8  19.8   305   11    6   4.5   2.5   11.9  53.4    -2.1    480  2.4
 11000   -5.9  21.4   295   13    7   5.8   3.2   11.3  52.3    -2.7    439  2.2
 10500   -5.0  23.0   290   15    8   5.9   3.3   10.7  51.2    -3.3    398  2.0
 10250   -4.6  23.7   290   16    8   7.9   4.3   10.4  50.8    -3.6    376  1.9
 10000   -3.9  25.0   285   17    9   9.2   5.0   10.4  50.7    -3.6    349  1.8
  9750   -3.3  26.1   285   18    9   8.2   4.5   10.3  50.5    -3.7    322  1.6
  9500   -2.7  27.1   280   17    9   8.1   4.4   10.2  50.3    -3.9    297  1.5
  9250   -2.1  28.2   280   16    8   8.1   4.4   10.1  50.1    -4.0    271  1.4
  9000   -1.5  29.3   275   15    8   8.1   4.4    9.9  49.9    -4.1    246  1.3
  8750   -0.9  30.4   270   16    8   8.1   4.4    9.8  49.7    -4.3    221  1.1
  8500   -0.3  31.5   270   17    9   8.1   4.4    9.7  49.4    -4.4    195  1.0
  8250    0.3  32.5   265   18    9   8.1   4.4    9.6  49.2    -4.6    170  0.9
  8000    0.9  33.6   265   19   10   8.1   4.4    9.4  49.0    -4.7    145  0.7
  7750    1.5  34.7   260   18    9   8.1   4.4    9.3  48.7    -4.8    119  0.6
  7500    2.1  35.8   260   16    8   8.1   4.4    9.2  48.5    -5.0     94  0.5
  7250    2.7  36.9   255   15    8   8.1   4.4    9.0  48.3    -5.1     68  0.3
  7000    3.3  37.9   250   14    7   8.1   4.5    8.9  48.1    -5.3     43  0.2
  6750    3.9  39.0   235   13    7   8.0   4.4    8.8  47.8    -5.4     18  0.1
  6500    4.5  40.1   220   13    7   8.4   4.6    8.6  47.6    -5.6      M    M
  6250    5.0  41.0   210   13    7  -0.2  -0.1    8.3  47.0    -5.9      M    M
  6000    4.8  40.6   195   15    8   3.3   1.8    7.4  45.4    -6.8      M    M
  5750    4.6  40.3   190   11    6 -25.4 -14.0    6.5  43.8    -7.8      M    M
  5500    0.1  32.2   185    8    4 -86.0 -47.2    1.3  34.4   -13.0     95  0.5

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

           12/21/2014 at 0800 MST          |       12/21/2014 at 1100 MST
                                           |
K index... +15.4  LI... +3.4               | K index... +10.2  LI... +3.6
CAPE... 0.0  CIN... -0.5                   | 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 -56.0 -68.8  335  22 11  -0.2  -0.1 | -56.8 -70.2  335  15  8   0.6   0.3
 45000 -56.3 -69.3  330  26 13  -0.2  -0.1 | -56.0 -68.8  325  20 10   0.7   0.4
 40000 -56.5 -69.7  325  52 27  -0.1  -0.1 | -56.3 -69.3  325  50 26  -0.3  -0.2
 38000 -56.2 -69.2  325  62 32   1.8   1.0 | -56.2 -69.2  325  61 31   1.3   0.7
 36000 -55.1 -67.2  330  67 34   1.9   1.0 | -55.4 -67.7  330  70 36   1.3   0.7
 34000 -54.0 -65.2  335  72 37   2.1   1.1 | -54.6 -66.3  335  79 41   2.2   1.2
 32000 -51.8 -61.2  330  67 34   3.9   2.1 | -51.5 -60.7  330  77 39   5.4   3.0
 30000 -48.9 -56.0  325  60 31   9.4   5.2 | -47.6 -53.7  325  75 38  10.1   5.5
 29000 -45.9 -50.6  320  57 30   9.8   5.4 | -44.6 -48.3  320  74 38   9.8   5.4
 28000 -43.0 -45.4  320  55 28   9.8   5.4 | -41.7 -43.1  320  74 38   9.8   5.4
 27000 -40.1 -40.2  315  52 27  10.0   5.5 | -38.8 -37.8  320  73 38  10.0   5.5
 26000 -37.4 -35.3  315  49 25   8.6   4.7 | -36.1 -33.0  315  70 36   8.4   4.6
 25000 -34.8 -30.6  315  46 23   8.6   4.7 | -33.6 -28.5  315  65 34   8.4   4.6
 24000 -32.3 -26.1  315  42 22   8.6   4.7 | -31.1 -24.0  315  61 31   8.5   4.7
 23000 -29.8 -21.6  315  40 21   7.9   4.4 | -28.9 -20.0  315  54 28   7.0   3.9
 22000 -27.5 -17.5  315  38 20   8.0   4.4 | -26.8 -16.2  315  46 24   7.0   3.8
 21000 -25.1 -13.2  315  36 19   8.0   4.4 | -24.7 -12.5  310  38 20   7.1   3.9
 20000 -22.9  -9.2  315  36 18   7.4   4.1 | -22.1  -7.8  315  35 18   9.0   5.0
 19500 -21.8  -7.2  315  36 18   7.4   4.1 | -20.8  -5.4  315  34 17   9.0   5.0
 19000 -20.7  -5.3  315  36 18   7.5   4.1 | -19.4  -2.9  315  33 17   9.0   5.0
 18500 -19.6  -3.3  315  35 18   7.5   4.1 | -18.1  -0.6  320  32 16   9.1   5.0
 18000 -18.5  -1.3  320  35 18   7.3   4.0 | -16.7   1.9  320  31 16   8.7   4.8
 17500 -17.4   0.7  320  36 18   7.3   4.0 | -15.4   4.3  320  31 16   8.7   4.8
 17000 -16.3   2.7  320  36 19   7.3   4.0 | -14.1   6.6  320  31 16   8.2   4.5
 16500 -15.2   4.6  320  37 19   7.3   4.0 | -13.0   8.6  320  31 16   7.8   4.3
 16000 -14.2   6.4  320  38 20   7.3   4.0 | -11.8  10.8  320  31 16   7.8   4.3
 15500 -13.1   8.4  320  38 20   7.3   4.0 | -10.3  13.5  320  32 16   6.6   3.6
 15000 -11.5  11.3  320  38 20   7.3   4.0 |  -9.3  15.3  320  32 17   6.6   3.6
 14500 -10.4  13.3  315  38 20   7.4   4.1 |  -8.4  16.9  320  33 17   6.6   3.6
 14000  -9.3  15.3  315  38 20   7.4   4.0 |  -7.4  18.7  320  33 17   6.6   3.6
 13500  -8.2  17.2  315  38 20   6.7   3.7 |  -6.4  20.5  315  35 18   6.6   3.6
 13000  -7.2  19.0  315  39 20   6.8   3.7 |  -5.5  22.1  315  36 19   6.8   3.7
 12500  -6.3  20.7  310  38 20   5.2   2.9 |  -4.6  23.7  310  38 19   5.2   2.9
 12000  -5.5  22.1  310  38 19   5.5   3.0 |  -3.8  25.2  310  39 20   5.5   3.0
 11500  -4.8  23.4  305  37 19   3.8   2.1 |  -3.1  26.4  310  41 21   4.4   2.4
 11000  -4.3  24.3  305  37 19   4.0   2.2 |  -2.4  27.7  305  41 21   4.7   2.6
 10500  -3.7  25.3  300  35 18   3.8   2.1 |  -1.9  28.6  300  41 21   2.6   1.4
 10250  -3.4  25.9  300  34 17   3.8   2.1 |  -1.7  28.9  300  41 21   2.8   1.5
 10000  -3.1  26.4  295  33 17   3.8   2.1 |  -1.5  29.3  300  40 20   4.0   2.2
  9750  -2.9  26.8  295  31 16   3.9   2.2 |  -1.1  30.0  295  38 20   4.1   2.3
  9500  -2.6  27.3  295  28 14   4.0   2.2 |  -0.9  30.4  295  36 18   3.2   1.8
  9250  -2.3  27.9  290  25 13   4.2   2.3 |  -0.6  30.9  295  33 17   3.8   2.1
  9000  -2.0  28.4  285  22 11   3.5   1.9 |  -0.4  31.3  290  31 16   2.5   1.3
  8750  -1.7  28.9  285  20 10   4.0   2.2 |  -0.2  31.6  290  29 15   3.4   1.8
  8500  -1.3  29.7  280  17  9   5.4   3.0 |   0.2  32.4  285  25 13   5.4   3.0
  8250  -1.0  30.2  270  14  7   4.3   2.4 |   0.5  32.9  280  22 12   4.5   2.5
  8000  -0.6  30.9  260  11  6   7.2   3.9 |   0.9  33.6  275  20 10   6.1   3.3
  7750   0.1  32.2  240  10  5   9.0   4.9 |   1.4  34.5  270  16  8   6.7   3.7
  7500   0.7  33.3  230   9  5   7.5   4.1 |   1.9  35.4  260  15  8   5.8   3.2
  7250   1.3  34.3  215   9  5   8.1   4.4 |   2.3  36.1  250  13  7   5.9   3.3
  7000   1.9  35.4  205  10  5   8.9   4.9 |   2.8  37.0  235  13  7   7.9   4.3
  6750   2.6  36.7  200  10  5   8.6   4.7 |   3.5  38.3  230  13  7   8.6   4.7
  6500   3.2  37.8  200  11  5  10.5   5.7 |   4.1  39.4  220  13  7   8.1   4.5
  6250   3.9  39.0  195  11  6   1.9   1.0 |   4.7  40.5  215  14  7   6.5   3.6
  6000   3.6  38.5  195  11  6  -4.6  -2.5 |   5.0  41.0  210  13  7   4.0   2.2
  5750   3.1  37.6  195  12  6 -14.1  -7.8 |   5.2  41.4  205  12  6   2.4   1.3
  5500   0.9  33.6  190  12  6 -43.7 -24.0 |   5.3  41.5  200   9  5   1.0   0.5

           12/21/2014 at 1400 MST          |       12/21/2014 at 1700 MST
                                           |
K index... +16.2  LI... +2.9               | K index... +13.8  LI... +2.6
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -57.2 -71.0  335  14  7   0.3   0.2 | -58.2 -72.8  335  16  8   2.4   1.3
 45000 -56.7 -70.1  330  17  9   0.3   0.1 | -54.6 -66.3  300  13  7   2.8   1.5
 40000 -55.9 -68.6  325  38 20   0.6   0.3 | -55.6 -68.1  320  44 23  -0.9  -0.5
 38000 -55.6 -68.1  325  50 26   0.4   0.2 | -55.7 -68.3  320  57 29   1.5   0.8
 36000 -55.3 -67.5  330  66 34   0.4   0.2 | -54.8 -66.6  325  69 35   1.5   0.8
 34000 -55.0 -67.0  330  83 43   1.5   0.8 | -53.7 -64.7  330  82 42   4.9   2.7
 32000 -50.5 -58.9  325  80 41   7.1   3.9 | -50.0 -58.0  325  82 42   6.1   3.4
 30000 -46.1 -51.0  320  76 39   8.7   4.8 | -46.2 -51.2  325  82 42   9.1   5.0
 29000 -43.6 -46.5  320  74 38   8.6   4.7 | -43.4 -46.1  325  79 41   9.3   5.1
 28000 -41.0 -41.8  320  72 37   8.6   4.7 | -40.6 -41.1  320  76 39   9.3   5.1
 27000 -38.4 -37.1  320  70 36   8.6   4.7 | -37.8 -36.0  320  74 38   9.4   5.2
 26000 -36.0 -32.8  315  68 35   8.1   4.5 | -35.3 -31.5  320  73 38   8.1   4.5
 25000 -33.5 -28.3  315  66 34   8.2   4.5 | -32.8 -27.0  320  73 38   8.2   4.5
 24000 -31.1 -24.0  315  65 33   8.2   4.5 | -30.4 -22.7  320  74 38   8.2   4.5
 23000 -28.6 -19.5  310  62 32   8.2   4.5 | -28.2 -18.8  320  72 37   6.9   3.8
 22000 -26.2 -15.2  310  58 30   8.3   4.5 | -26.1 -15.0  320  68 35   6.8   3.7
 21000 -23.7 -10.7  305  54 28   8.4   4.6 | -24.1 -11.4  320  65 34   6.8   3.7
 20000 -21.5  -6.7  305  48 25   7.3   4.0 | -21.9  -7.4  320  64 33   7.6   4.2
 19500 -20.4  -4.7  300  45 23   7.3   4.0 | -20.8  -5.4  320  64 33   7.6   4.2
 19000 -19.3  -2.7  300  42 22   7.4   4.0 | -19.6  -3.3  320  63 33   7.6   4.2
 18500 -18.2  -0.8  300  39 20   7.3   4.0 | -18.5  -1.3  320  63 32   7.6   4.1
 18000 -17.1   1.2  300  37 19   7.6   4.1 | -16.8   1.8  320  64 33   7.9   4.3
 17500 -16.0   3.2  305  37 19   7.6   4.2 | -15.6   3.9  320  65 33   8.0   4.4
 17000 -14.9   5.2  310  37 19   7.6   4.2 | -14.5   5.9  320  66 34   7.5   4.1
 16500 -13.2   8.2  315  41 21   7.5   4.1 | -13.4   7.9  320  65 34   7.5   4.1
 16000 -12.1  10.2  315  44 22   6.8   3.7 | -12.3   9.9  320  65 34   7.9   4.3
 15500 -11.2  11.8  320  45 23   6.3   3.5 | -11.0  12.2  320  65 34   8.4   4.6
 15000 -10.2  13.6  325  46 24   6.7   3.7 |  -9.8  14.4  320  66 34   8.3   4.5
 14500  -9.1  15.6  325  47 24   8.1   4.5 |  -8.7  16.3  320  66 34   6.6   3.6
 14000  -7.9  17.8  325  48 24   8.1   4.4 |  -7.7  18.1  320  65 34   6.6   3.6
 13500  -6.8  19.8  330  49 25   6.2   3.4 |  -6.7  19.9  320  65 33   7.3   4.0
 13000  -5.9  21.4  330  50 26   6.3   3.5 |  -5.6  21.9  320  63 32   7.4   4.0
 12500  -4.9  23.2  330  51 26   7.3   4.0 |  -4.6  23.7  320  61 31   6.1   3.3
 12000  -3.8  25.2  325  51 26   7.3   4.0 |  -3.7  25.3  315  58 30   5.9   3.3
 11500  -2.8  27.0  325  51 26   6.1   3.3 |  -2.8  27.0  315  55 29   7.0   3.8
 11000  -1.9  28.6  320  51 26   6.2   3.4 |  -1.7  28.9  310  53 27   7.2   3.9
 10500  -1.1  30.0  315  49 25   4.7   2.6 |  -0.7  30.7  310  51 26   6.4   3.5
 10250  -0.8  30.6  315  49 25   4.8   2.6 |  -0.2  31.6  310  51 26   6.2   3.4
 10000  -0.4  31.3  315  48 25   4.9   2.7 |   0.2  32.4  305  50 26   5.8   3.2
  9750  -0.0  32.0  310  46 24   5.2   2.8 |   0.6  33.1  305  49 25   5.8   3.2
  9500   0.3  32.5  310  44 23   5.1   2.8 |   1.1  34.0  300  48 25   6.2   3.4
  9250   0.7  33.3  305  43 22   5.6   3.1 |   1.5  34.7  300  47 24   6.6   3.6
  9000   1.1  34.0  305  41 21   3.7   2.0 |   2.0  35.6  295  45 23   5.0   2.7
  8750   1.3  34.3  300  39 20   4.5   2.5 |   2.3  36.1  295  44 23   4.6   2.5
  8500   1.8  35.2  300  36 19   7.0   3.9 |   2.7  36.9  295  41 21   5.9   3.2
  8250   2.3  36.1  300  34 17   6.0   3.3 |   3.1  37.6  290  38 20   6.0   3.3
  8000   2.8  37.0  300  31 16   7.7   4.2 |   3.5  38.3  290  36 18   4.3   2.4
  7750   3.4  38.1  300  28 14   8.1   4.5 |   3.8  38.8  285  33 17   4.8   2.6
  7500   3.9  39.0  295  26 13   7.1   3.9 |   4.3  39.7  285  30 16   7.0   3.8
  7250   4.5  40.1  295  23 12   7.2   4.0 |   4.8  40.6  285  28 14   6.4   3.5
  7000   5.0  41.0  295  21 11   7.9   4.3 |   5.3  41.5  280  25 13   6.6   3.6
  6750   5.6  42.1  295  19 10   8.0   4.4 |   5.8  42.4  280  22 11   7.4   4.0
  6500   6.2  43.2  290  16  8   7.1   3.9 |   6.4  43.5  280  20 10   8.0   4.4
  6250   6.7  44.1  290  14  7   7.7   4.2 |   6.9  44.4  280  17  9   7.5   4.1
  6000   7.3  45.1  285  12  6   8.5   4.7 |   7.5  45.5  275  15  8   6.6   3.6
  5750   8.0  46.4  280   9  5   8.3   4.6 |   7.9  46.2  270  12  6   3.9   2.1
  5500   8.5  47.3  270   6  3   6.9   3.8 |   8.0  46.4  260   8  4   0.8   0.5
________________________________________________________________________________

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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