Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 240040
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1740 MST Tuesday, December 23, 2014

This forecast is for Wednesday, December 24, 2014:

If the trigger temperature of 39.1 F/4.0 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 389 ft/min (2.0 m/s)
   Maximum height of thermals.................. 11391 ft MSL (6104 ft AGL)

Forecast maximum temperature................... 48.0 F/9.3 C
Time of trigger temperature.................... 1030 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................. 10129 ft MSL (4842 ft AGL)
Thermal soaring outlook for Thursday 12/25..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Improving.
Height of stable layer (12-18K ft MSL)......... 12420 ft MSL (7133 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 34065 ft MSL (28778 ft AGL)
Wave soaring outlook for Thursday 12/25........ Fair

Remarks... Fair early Thursday...poor by afternoon.

Sunrise/Sunset.................... 07:18:22 / 16:40:03 MST
Total possible sunshine........... 9 hr 21 min 40 sec (561 min 40 sec)
Altitude of sun at 11:59:11 MST... 26.90 degrees

Upper air data from numerical model forecast valid on 12/24/2014 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 20607 ft MSL (15320 ft AGL)
Lifted condensation level....... 15931 ft MSL (10643 ft AGL)
Lifted index.................... +12.1
K index......................... -11.0

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  -55.2 -67.4   325   39   20   1.6   0.9      M     M       M      M    M
 45000  -52.8 -63.0   340   53   27   1.3   0.7      M     M       M      M    M
 40000  -51.6 -60.9   345   61   32   0.8   0.4      M     M       M      M    M
 38000  -51.8 -61.2   345   67   35  -2.3  -1.3      M     M       M      M    M
 36000  -53.2 -63.8   350   79   40  -2.3  -1.3      M     M       M      M    M
 34000  -54.5 -66.1   355   90   46   0.6   0.3      M     M       M      M    M
 32000  -50.6 -59.1   355   84   43   6.9   3.8      M     M       M      M    M
 30000  -45.9 -50.6   355   76   39   8.8   4.8   30.4  86.8    16.1      M    M
 29000  -43.3 -45.9   355   76   39   8.5   4.7   29.8  85.7    15.9      M    M
 28000  -40.8 -41.4   360   77   39   8.5   4.7   29.3  84.8    15.7      M    M
 27000  -38.2 -36.8   360   77   40   8.6   4.7   29.0  84.2    15.6      M    M
 26000  -35.8 -32.4   005   74   38   7.9   4.3   28.3  82.9    15.2      M    M
 25000  -33.4 -28.1   005   70   36   7.9   4.3   27.5  81.6    14.8      M    M
 24000  -31.1 -24.0   005   67   34   8.0   4.4   26.9  80.4    14.5      M    M
 23000  -29.1 -20.4   005   64   33   5.7   3.1   25.7  78.2    13.7      M    M
 22000  -27.4 -17.3   005   61   31   5.7   3.1   24.2  75.5    12.6      M    M
 21000  -25.7 -14.3   360   59   30   5.8   3.2   22.8  73.1    11.6      M    M
 20000  -23.6 -10.5   360   57   29   7.3   4.0   21.8  71.2    10.8      M    M
 19500  -22.6  -8.7   360   56   29   7.3   4.0   21.3  70.4    10.5      M    M
 19000  -21.5  -6.7   360   55   29   7.3   4.0   20.9  69.6    10.2      M    M
 18500  -20.4  -4.7   360   55   28   7.1   3.9   20.5  68.9     9.9      M    M
 18000  -19.2  -2.6   355   54   28   8.7   4.8   20.2  68.4     9.7      M    M
 17500  -17.9  -0.2   360   53   27   8.5   4.7   20.0  68.0     9.6      M    M
 17000  -16.7   1.9   360   52   27   7.2   3.9   19.8  67.6     9.4      M    M
 16500  -15.8   3.6   360   52   27   6.2   3.4   19.2  66.5     8.9      M    M
 16000  -14.9   5.2   360   52   27   6.2   3.4   18.6  65.4     8.4      M    M
 15500  -14.0   6.8   360   51   26   6.5   3.5   18.0  64.4     7.9      M    M
 15000  -12.6   9.3   355   50   26   6.2   3.4   17.2  62.9     7.2      M    M
 14500  -11.7  10.9   355   49   25   5.8   3.2   16.5  61.7     6.6      M    M
 14000  -10.8  12.6   355   48   25   5.1   2.8   15.9  60.6     6.1      M    M
 13500  -10.3  13.5   355   46   24   2.5   1.4   14.8  58.6     5.2      M    M
 13000   -9.8  14.4   350   45   23   2.4   1.3   13.6  56.6     4.2      M    M
 12500   -9.7  14.5   350   43   22  -0.3  -0.2   12.2  53.9     2.9      M    M
 12000   -9.7  14.5   345   40   21  -0.0  -0.0   10.6  51.0     1.5      M    M
 11500   -9.6  14.7   345   37   19   1.2   0.6    9.1  48.4     0.1      M    M
 11000   -9.4  15.1   340   34   17   1.3   0.7    7.7  45.9    -1.2    371  1.9
 10500   -9.1  15.6   345   30   15   2.9   1.6    6.5  43.8    -2.3    346  1.8
 10250   -8.9  16.0   345   27   14   3.1   1.7    6.0  42.8    -2.8    333  1.7
 10000   -8.6  16.5   345   25   13   1.8   1.0    5.5  41.8    -3.4    319  1.6
  9750   -8.5  16.7   345   24   12   2.8   1.5    4.8  40.7    -4.0    308  1.6
  9500   -8.2  17.2   345   21   11   4.9   2.7    4.4  39.9    -4.4    291  1.5
  9250   -7.9  17.8   345   18    9   4.5   2.5    4.0  39.2    -4.8    274  1.4
  9000   -7.6  18.3   345   16    8   4.1   2.2    3.6  38.4    -5.2    257  1.3
  8750   -7.2  19.0   340   13    7   5.7   3.1    3.2  37.7    -5.7    240  1.2
  8500   -6.7  19.9   335   11    6   7.1   3.9    2.9  37.3    -5.9    217  1.1
  8250   -6.2  20.8   325   10    5   7.4   4.1    2.7  36.9    -6.1    195  1.0
  8000   -5.6  21.9   320    9    5   9.2   5.1    2.6  36.7    -6.3    168  0.9
  7750   -4.9  23.2   320    9    5   9.7   5.3    2.6  36.7    -6.3    140  0.7
  7500   -4.1  24.6   320   10    5  10.4   5.7    2.6  36.7    -6.3    110  0.6
  7250   -3.5  25.7   320   10    5   4.7   2.6    2.5  36.6    -6.4     83  0.4
  7000   -3.4  25.9   310   13    7   1.0   0.6    1.9  35.4    -7.1     73  0.4
  6750   -3.3  26.1   305   16    8  -1.3  -0.7    1.2  34.2    -7.7     63  0.3
  6500   -3.6  25.5   295   19   10  -4.6  -2.5    0.2  32.3    -8.8     66  0.3
  6250   -3.9  25.0   290   18    9  -2.8  -1.5   -0.8  30.5    -9.8     66  0.3
  6000   -4.1  24.6   280   15    8  -2.5  -1.4   -1.8  28.8   -10.8     66  0.3
  5750   -4.4  24.1   270   13    7  -3.9  -2.2   -2.7  27.1   -11.8     65  0.3
  5500   -4.9  23.2   255   10    5 -11.1  -6.1   -3.9  24.9   -13.1     74  0.4

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

           12/24/2014 at 0800 MST          |       12/24/2014 at 1100 MST
                                           |
K index... -1.0  LI... +6.6                | K index... -5.2  LI... +7.4
CAPE... 0.0  CIN... -0.2                   | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -56.4 -69.5  320  42 22   1.9   1.0 | -57.3 -71.1  305  38 19   2.9   1.6
 45000 -53.5 -64.3  325  60 31   2.2   1.2 | -52.8 -63.0  315  53 27   1.0   0.5
 40000 -55.1 -67.2  340  63 32  -1.2  -0.6 | -55.9 -68.6  330  53 27  -2.1  -1.2
 38000 -55.4 -67.7  345  67 35   0.7   0.4 | -56.3 -69.3  335  57 29   1.6   0.9
 36000 -55.0 -67.0  345  75 38   0.6   0.4 | -55.4 -67.7  335  65 34   1.5   0.8
 34000 -54.6 -66.3  345  82 42   4.0   2.2 | -54.4 -65.9  335  73 38   5.5   3.0
 32000 -50.4 -58.7  345  74 38   7.0   3.9 | -49.8 -57.6  335  64 33   7.7   4.2
 30000 -46.1 -51.0  345  65 34   7.9   4.4 | -44.6 -48.3  330  55 29   8.1   4.4
 29000 -43.1 -45.6  345  62 32   8.3   4.5 | -42.2 -44.0  335  53 27   8.1   4.4
 28000 -40.6 -41.1  345  59 31   8.3   4.5 | -39.8 -39.6  335  50 26   8.1   4.4
 27000 -38.1 -36.6  350  57 29   8.3   4.5 | -37.3 -35.1  340  47 24   8.0   4.4
 26000 -35.6 -32.1  350  56 29   8.4   4.6 | -35.2 -31.4  340  45 23   7.1   3.9
 25000 -33.1 -27.6  350  54 28   8.4   4.6 | -33.1 -27.6  335  43 22   7.1   3.9
 24000 -30.6 -23.1  350  53 27   8.4   4.6 | -30.9 -23.6  335  41 21   7.0   3.9
 23000 -28.1 -18.6  355  50 26   8.0   4.4 | -28.7 -19.7  340  36 18   7.8   4.3
 22000 -25.7 -14.3  005  47 24   8.0   4.4 | -26.3 -15.3  350  30 16   7.8   4.3
 21000 -23.3  -9.9  015  45 23   7.7   4.2 | -24.0 -11.2  360  26 13   8.1   4.4
 20000 -21.5  -6.7  010  43 22   5.7   3.1 | -21.4  -6.5  350  25 13   9.0   4.9
 19500 -20.7  -5.3  005  42 21   5.7   3.1 | -20.0  -4.0  345  25 13   9.0   4.9
 19000 -19.8  -3.6  005  41 21   5.7   3.1 | -18.7  -1.7  340  25 13   9.0   4.9
 18500 -19.0  -2.2  360  40 21   5.6   3.1 | -17.3   0.9  335  26 13   9.0   4.9
 18000 -18.1  -0.6  355  40 20   6.7   3.7 | -16.0   3.2  330  27 14   8.6   4.7
 17500 -17.1   1.2  355  39 20   6.6   3.6 | -14.7   5.5  330  28 14   8.6   4.7
 17000 -16.1   3.0  355  39 20   6.3   3.5 | -13.5   7.7  335  28 15   7.1   3.9
 16500 -15.2   4.6  350  39 20   6.2   3.4 | -12.5   9.5  335  28 14   6.5   3.6
 16000 -14.3   6.3  350  39 20   6.2   3.4 | -11.5  11.3  335  27 14   6.2   3.4
 15500 -13.4   7.9  350  39 20   6.1   3.4 | -10.7  12.7  335  27 14   5.2   2.9
 15000 -12.5   9.5  350  39 20   6.1   3.3 |  -9.6  14.7  340  28 15   4.9   2.7
 14500 -11.1  12.0  350  39 20   6.7   3.7 |  -8.9  16.0  340  28 15   4.6   2.5
 14000 -10.1  13.8  350  39 20   6.4   3.5 |  -8.3  17.1  335  28 15   4.4   2.4
 13500  -9.2  15.4  350  38 19   5.6   3.1 |  -7.7  18.1  335  28 14   3.7   2.1
 13000  -8.4  16.9  350  37 19   5.4   3.0 |  -7.2  19.0  335  27 14   3.8   2.1
 12500  -7.8  18.0  350  35 18   3.8   2.1 |  -6.6  20.1  335  25 13   3.6   2.0
 12000  -7.2  19.0  345  34 17   3.8   2.1 |  -6.1  21.0  330  23 12   3.7   2.0
 11500  -6.7  19.9  345  32 17   3.5   1.9 |  -5.5  22.1  330  22 11   4.3   2.3
 11000  -6.1  21.0  345  30 16   3.6   2.0 |  -4.9  23.2  335  20 10   4.2   2.3
 10500  -5.5  22.1  345  29 15   3.8   2.1 |  -4.3  24.3  335  18  9   4.2   2.3
 10250  -5.3  22.5  345  28 14   3.6   2.0 |  -4.0  24.8  335  17  9   3.7   2.0
 10000  -5.0  23.0  345  27 14   4.4   2.4 |  -3.7  25.3  335  16  8   5.7   3.1
  9750  -4.6  23.7  345  25 13   3.1   1.7 |  -3.2  26.2  330  15  7   5.7   3.1
  9500  -4.5  23.9  345  22 12   1.3   0.7 |  -2.9  26.8  330  13  7   3.7   2.0
  9250  -4.4  24.1  345  20 10   1.9   1.0 |  -2.6  27.3  325  12  6   4.1   2.2
  9000  -4.2  24.4  345  18  9   1.1   0.6 |  -2.3  27.9  315  11  5   4.5   2.5
  8750  -4.1  24.6  340  14  7   1.6   0.9 |  -1.9  28.6  310  10  5   5.4   2.9
  8500  -4.0  24.8  330  12  6   2.3   1.3 |  -1.5  29.3  300  10  5   5.4   3.0
  8250  -3.8  25.2  320   9  5   2.7   1.5 |  -1.1  30.0  290  10  5   5.4   2.9
  8000  -3.5  25.7  310   8  4   6.2   3.4 |  -0.6  30.9  285  11  5   7.8   4.3
  7750  -2.9  26.8  305   7  4   7.3   4.0 |   0.0  32.0  285  11  6   7.8   4.3
  7500  -2.4  27.7  310   7  4   6.6   3.6 |   0.5  32.9  290  12  6   7.0   3.8
  7250  -2.0  28.4  315   7  4   5.6   3.1 |   1.0  33.8  290  13  7   4.2   2.3
  7000  -1.6  29.1  315   9  5   5.0   2.8 |   1.1  34.0  295  14  7  -0.7  -0.4
  6750  -1.3  29.7  310  11  6   2.5   1.4 |   0.9  33.6  295  16  8  -2.9  -1.6
  6500  -1.4  29.5  305  14  7  -4.3  -2.4 |   0.6  33.1  290  16  8  -4.4  -2.4
  6250  -1.9  28.6  295  14  7 -11.2  -6.1 |   0.3  32.5  285  15  8  -5.0  -2.7
  6000  -2.9  26.8  280  13  6 -14.3  -7.9 |  -0.1  31.8  275  12  6  -5.3  -2.9
  5750  -3.9  25.0  265  12  6 -12.1  -6.7 |  -0.6  30.9  260   9  4  -6.7  -3.7
  5500  -4.8  23.4  240  10  5 -12.7  -7.0 |  -1.1  30.0  220   5  3  -3.9  -2.1

           12/24/2014 at 1400 MST          |       12/24/2014 at 1700 MST
                                           |
K index... -0.8  LI... +6.7                | K index... -0.2  LI... +6.0
CAPE... 0.0  CIN... M                      | 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 -58.2 -72.8  290  42 21   3.2   1.8 | -57.7 -71.9  280  42 22   2.9   1.6
 45000 -53.3 -63.9  300  54 28   3.7   2.0 | -53.4 -64.1  290  50 26   3.3   1.8
 40000 -55.9 -68.6  315  52 27  -1.9  -1.1 | -56.1 -69.0  305  55 28  -2.0  -1.1
 38000 -56.2 -69.2  320  55 28   1.8   1.0 | -56.4 -69.5  310  58 30   1.8   1.0
 36000 -55.2 -67.4  320  62 32   1.8   1.0 | -55.4 -67.7  310  63 32   1.7   1.0
 34000 -54.1 -65.4  320  69 35   5.5   3.0 | -54.3 -65.7  310  67 35   5.9   3.2
 32000 -49.4 -56.9  315  62 32   7.7   4.2 | -49.2 -56.6  305  58 30   8.5   4.7
 30000 -44.8 -48.6  315  56 29   8.0   4.4 | -44.1 -47.4  300  49 25   8.1   4.4
 29000 -41.9 -43.4  315  50 26   7.9   4.3 | -41.8 -43.2  300  48 25   7.6   4.2
 28000 -39.5 -39.1  310  46 24   7.9   4.3 | -39.6 -39.3  300  47 24   7.6   4.2
 27000 -37.2 -35.0  310  42 22   7.9   4.3 | -36.7 -34.1  295  46 24   7.7   4.2
 26000 -34.8 -30.6  310  39 20   8.0   4.4 | -34.7 -30.5  295  44 23   6.5   3.6
 25000 -32.4 -26.3  310  37 19   8.0   4.4 | -32.7 -26.9  295  41 21   6.5   3.6
 24000 -30.1 -22.2  310  34 18   8.1   4.4 | -30.8 -23.4  295  38 20   6.5   3.5
 23000 -27.9 -18.2  310  33 17   6.9   3.8 | -28.5 -19.3  295  37 19   8.0   4.4
 22000 -25.9 -14.6  305  31 16   6.9   3.8 | -26.1 -15.0  290  35 18   8.0   4.4
 21000 -23.8 -10.8  305  30 15   7.2   3.9 | -23.7 -10.7  290  34 18   8.0   4.4
 20000 -21.2  -6.2  300  28 14   8.9   4.9 | -21.4  -6.5  285  32 16   7.8   4.3
 19500 -19.9  -3.8  295  27 14   8.9   4.9 | -20.3  -4.5  285  31 16   7.8   4.3
 19000 -18.5  -1.3  295  26 13   8.9   4.9 | -19.1  -2.4  285  29 15   7.8   4.3
 18500 -17.2   1.0  290  25 13   9.1   5.0 | -17.9  -0.2  285  28 14   8.0   4.4
 18000 -15.9   3.4  290  24 12   7.0   3.8 | -16.9   1.6  285  27 14   5.8   3.2
 17500 -14.9   5.2  285  23 12   7.2   4.0 | -16.0   3.2  290  26 13   5.9   3.3
 17000 -13.8   7.2  285  22 11   6.8   3.7 | -15.1   4.8  300  25 13   6.0   3.3
 16500 -12.8   9.0  290  22 11   6.5   3.6 | -14.3   6.3  305  24 12   6.1   3.3
 16000 -11.9  10.6  295  21 11   6.4   3.5 | -13.4   7.9  310  23 12   6.1   3.3
 15500 -11.0  12.2  300  22 11   5.2   2.9 | -12.4   9.7  315  23 12   6.4   3.5
 15000 -10.3  13.5  305  23 12   5.4   3.0 | -11.5  11.3  320  23 12   6.3   3.4
 14500  -9.2  15.4  310  23 12   4.6   2.5 | -10.5  13.1  320  22 12   7.2   3.9
 14000  -8.6  16.5  315  23 12   4.7   2.6 |  -8.9  16.0  325  22 11   7.2   4.0
 13500  -7.8  18.0  315  22 12   5.9   3.2 |  -7.9  17.8  325  21 11   7.0   3.8
 13000  -6.9  19.6  320  21 11   5.8   3.2 |  -6.8  19.8  325  20 10   7.0   3.8
 12500  -6.1  21.0  320  20 10   5.2   2.9 |  -5.8  21.6  325  18  9   6.9   3.8
 12000  -5.3  22.5  320  18 10   5.3   2.9 |  -4.8  23.4  325  17  9   6.8   3.7
 11500  -4.6  23.7  320  17  9   5.0   2.7 |  -3.7  25.3  320  15  8   7.9   4.3
 11000  -3.8  25.2  315  14  7   5.1   2.8 |  -2.5  27.5  315  14  7   7.6   4.2
 10500  -3.2  26.2  315  12  6   3.9   2.1 |  -1.3  29.7  315  14  7   9.3   5.1
 10250  -2.9  26.8  310  11  6   4.0   2.2 |  -0.6  30.9  315  15  7   9.2   5.0
 10000  -2.5  27.5  305  10  5   5.6   3.1 |   0.1  32.2  315  15  8  10.1   5.6
  9750  -2.1  28.2  300   9  5   7.0   3.9 |   0.9  33.6  315  16  8   8.7   4.7
  9500  -1.6  29.1  300   9  5   6.7   3.7 |   1.4  34.5  310  17  9   6.9   3.8
  9250  -1.1  30.0  295   9  5   7.0   3.8 |   2.0  35.6  305  18  9   7.6   4.2
  9000  -0.5  31.1  290   9  5   6.2   3.4 |   2.5  36.5  305  19 10   6.7   3.7
  8750  -0.1  31.8  290   9  5   7.3   4.0 |   2.9  37.2  300  20 10   2.3   1.3
  8500   0.5  32.9  290  10  5   8.6   4.7 |   2.9  37.2  295  21 11  -0.0  -0.0
  8250   1.2  34.2  295  11  6   8.8   4.8 |   2.9  37.2  290  21 11   0.5   0.3
  8000   1.8  35.2  295  12  6   6.8   3.7 |   2.9  37.2  290  22 11   1.0   0.5
  7750   2.1  35.8  295  16  8   2.0   1.1 |   2.9  37.2  280  20 10   2.0   1.1
  7500   2.1  35.8  295  17  9   0.8   0.4 |   3.1  37.6  275  18  9   2.2   1.2
  7250   2.2  36.0  295  19 10   1.1   0.6 |   3.2  37.8  270  16  8   2.0   1.1
  7000   2.2  36.0  290  19 10   0.3   0.2 |   3.4  38.1  260  15  7   3.8   2.1
  6750   2.3  36.1  280  16  8   1.1   0.6 |   3.7  38.7  255  12  6   4.9   2.7
  6500   2.4  36.3  275  13  7   1.8   1.0 |   4.0  39.2  245  10  5   4.6   2.5
  6250   2.5  36.5  265  10  5   2.4   1.3 |   4.4  39.9  230   8  4   3.5   1.9
  6000   2.7  36.9  250   8  4   3.4   1.9 |   4.5  40.1  215   8  4   0.2   0.1
  5750   3.0  37.4  235   6  3   4.0   2.2 |   4.4  39.9  205   8  4   1.6   0.9
  5500   3.3  37.9  215   5  2   7.4   4.0 |   4.3  39.7  190   7  3  -8.6  -4.7
________________________________________________________________________________

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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