Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 241255
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0555 MST Saturday, January 24, 2015

This forecast is for Saturday, January 24, 2015:

If the trigger temperature of 58.5 F/14.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 7 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8209 ft MSL (2924 ft AGL)

Forecast maximum temperature................... 55.0 F/13.2 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6426 ft MSL (1141 ft AGL)
Thermal soaring outlook for Sunday 01/25....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Improving to fair or even good.
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 14392 ft MSL (9107 ft AGL)
Wave soaring outlook for Sunday 01/25.......... Fair

Remarks... Mountain wave conditions today with gusty west winds at times over
           and near the front range...then diminishing this evening.

Sunrise/Sunset.................... 07:13:53 / 17:08:17 MST
Total possible sunshine........... 9 hr 54 min 25 sec (594 min 25 sec)
Altitude of sun at 12:11:28 MST... 31.15 degrees

Upper air data from rawinsonde observation taken on 01/24/2015 at 0500 MST

Freezing level.................. 5300 ft MSL (15 ft AGL)
Additional freezing level....... 10605 ft MSL (5320 ft AGL)
Convective condensation level... 20837 ft MSL (15552 ft AGL)
Lifted condensation level....... 17311 ft MSL (12026 ft AGL)
Lifted index.................... +8.3
K index......................... -28.6

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  -58.3 -72.9   355   31   16   5.7   3.1  104.1 219.3    52.0      M    M
 45000  -57.1 -70.8   340   32   16   3.6   2.0   80.0 176.0    41.1      M    M
 40000  -53.9 -65.0   355   29   15   5.1   2.8   62.0 143.5    32.2      M    M
 38000  -62.2 -80.0   360   64   33   1.9   1.0   40.7 105.2    18.7      M    M
 36000  -59.9 -75.8   005   46   24   6.1   3.3   35.4  95.6    15.6      M    M
 34000  -55.3 -67.5   015   55   28   7.6   4.2   33.6  92.5    14.8      M    M
 32000  -50.6 -59.1   020   59   30   8.1   4.5   32.0  89.6    14.0      M    M
 30000  -45.1 -49.2   035   49   25   7.9   4.3   30.5  87.0    13.3      M    M
 29000  -42.7 -44.9   035   47   24   8.1   4.5   29.8  85.6    12.9      M    M
 28000  -40.9 -41.6   035   45   23   5.3   2.9   28.3  83.0    12.0      M    M
 27000  -38.5 -37.3   030   43   22   8.7   4.8   27.6  81.7    11.6      M    M
 26000  -35.9 -32.6   030   41   21   8.7   4.8   27.2  81.0    11.4      M    M
 25000  -33.3 -27.9   030   39   20   8.7   4.7   27.0  80.5    11.3      M    M
 24000  -30.7 -23.3   025   36   19   5.7   3.1   26.5  79.7    11.1      M    M
 23000  -29.1 -20.4   010   31   16   6.7   3.7   24.8  76.7     9.9      M    M
 22000  -27.5 -17.5   355   28   14   5.0   2.7   23.3  73.9     8.7      M    M
 21000  -25.1 -13.2   335   28   14   9.5   5.2   22.6  72.7     8.2      M    M
 20000  -22.2  -8.0   335   29   15   9.3   5.1   22.5  72.6     8.3      M    M
 19500  -20.9  -5.6   335   31   16   8.4   4.6   22.3  72.2     8.1      M    M
 19000  -19.6  -3.3   340   33   17   9.5   5.2   22.1  71.8     8.0      M    M
 18500  -18.2  -0.8   340   31   16   8.3   4.5   22.1  71.7     8.0      M    M
 18000  -17.0   1.4   340   28   14   7.9   4.4   21.8  71.2     7.8      M    M
 17500  -15.8   3.6   340   25   13   7.3   4.0   21.5  70.6     7.6      M    M
 17000  -14.9   5.2   335   21   11   6.3   3.4   20.9  69.6     7.1      M    M
 16500  -13.9   7.0   335   18    9   7.6   4.2   20.4  68.7     6.7      M    M
 16000  -12.7   9.1   330   15    8   8.0   4.4   20.1  68.2     6.5      M    M
 15500  -11.4  11.5   335   15    8   8.0   4.4   19.8  67.6     6.2      M    M
 15000   -9.6  14.7   340   17    9   7.5   4.1   19.4  66.9     5.9      M    M
 14500   -8.6  16.5   345   19   10   6.5   3.6   18.9  65.9     5.5      M    M
 14000   -7.7  18.1   345   20   10   6.9   3.8   18.3  65.0     5.0      M    M
 13500   -6.6  20.1   345   18    9   7.8   4.3   18.0  64.3     4.7      M    M
 13000   -5.4  22.3   345   17    9   7.7   4.2   17.6  63.7     4.4      M    M
 12500   -4.3  24.3   350   15    8   7.7   4.2   17.3  63.2     4.1      M    M
 12000   -3.1  26.4   350   14    7   7.7   4.2   17.0  62.7     3.9      M    M
 11500   -2.0  28.4   345   13    7   7.7   4.2   16.7  62.0     3.6      M    M
 11000   -0.8  30.6   335   13    6   7.7   4.2   16.3  61.4     3.3      M    M
 10500    0.4  32.7   330   12    6   7.6   4.2   16.0  60.8     3.0      M    M
 10250    0.9  33.6   325   12    6   8.1   4.4   15.9  60.6     2.8      M    M
 10000    1.5  34.7   325   13    6   6.8   3.7   15.7  60.3     2.7      M    M
  9750    1.9  35.4   330   13    7   5.3   2.9   15.4  59.7     2.4      M    M
  9500    2.4  36.3   330   14    7   5.7   3.2   15.1  59.1     2.1      M    M
  9250    2.8  37.0   335   15    8   5.6   3.0   14.7  58.5     1.8      M    M
  9000    3.2  37.8   335   16    8   5.9   3.2   14.4  58.0     1.5      M    M
  8750    3.6  38.5   330   15    8   4.7   2.6   14.1  57.4     1.2      M    M
  8500    3.9  39.0   330   14    7   2.2   1.2   13.6  56.5     0.7      M    M
  8250    4.0  39.2   325   13    7   2.0   1.1   13.0  55.4     0.1      M    M
  8000    4.1  39.4   320   12    6   1.1   0.6   12.4  54.3    -0.5    197  1.0
  7750    4.2  39.6   315   11    6   5.9   3.2   11.8  53.3    -1.2    186  0.9
  7500    4.9  40.8   310   10    5  10.8   5.9   11.8  53.2    -1.2    157  0.8
  7250    5.6  42.1   305    9    5   8.9   4.9   11.8  53.2    -1.2    128  0.7
  7000    6.4  43.5   295    8    4  11.6   6.4   11.8  53.2    -1.2    100  0.5
  6750    7.1  44.8   280    9    4   2.7   1.5   11.8  53.2    -1.2     71  0.4
  6500    6.6  43.9   270   10    5 -12.1  -6.6   10.6  51.0    -2.5     78  0.4
  6250    5.8  42.4   260   11    6  -0.9  -0.5    9.1  48.4    -3.9     93  0.5
  6000    6.2  43.2   250   13    7   2.2   1.2    8.7  47.7    -4.3     76  0.4
  5750    5.2  41.4   245   10    5 -32.8 -18.0    7.0  44.6    -6.1     99  0.5
  5500    1.6  34.9   235    7    4 -54.5 -29.9    2.7  36.8   -10.5    199  1.0

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

           01/24/2015 at 0800 MST          |       01/24/2015 at 1100 MST
                                           |
K index... -23.6  LI... +6.0               | K index... -15.5  LI... +6.2
CAPE... 0.0  CIN... M                      | 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 -59.6 -75.3  340  31 16   2.7   1.5 | -59.7 -75.5  355  29 15   2.8   1.5
 45000 -55.4 -67.7  340  33 17  -0.2  -0.1 | -55.3 -67.5  350  34 18   0.4   0.2
 40000 -59.3 -74.7  355  38 20  -2.6  -1.4 | -57.4 -71.3  340  38 20  -1.4  -0.8
 38000 -59.3 -74.7  360  42 21   3.0   1.6 | -57.4 -71.3  340  40 21   1.4   0.8
 36000 -57.5 -71.5  355  45 23   3.0   1.6 | -56.6 -69.9  350  44 22   1.4   0.8
 34000 -55.3 -67.5  355  48 25   8.3   4.5 | -55.3 -67.5  350  47 24   7.6   4.2
 32000 -50.6 -59.1  355  40 20   7.7   4.2 | -50.6 -59.1  350  44 23   6.9   3.8
 30000 -45.3 -49.5  355  33 17   8.5   4.7 | -46.0 -50.8  350  41 21   9.3   5.1
 29000 -42.7 -44.9  355  32 16   8.6   4.7 | -43.2 -45.8  350  38 19   9.3   5.1
 28000 -40.2 -40.4  350  31 16   8.6   4.7 | -40.4 -40.7  350  35 18   9.3   5.1
 27000 -37.6 -35.7  350  30 15   8.3   4.6 | -37.6 -35.7  350  32 16   9.2   5.1
 26000 -35.1 -31.2  350  27 14   8.3   4.5 | -34.9 -30.8  345  32 16   9.2   5.1
 25000 -32.6 -26.7  350  25 13   8.3   4.5 | -32.1 -25.8  340  32 16   9.2   5.1
 24000 -30.2 -22.4  350  22 11   8.0   4.4 | -29.3 -20.7  330  33 17   8.6   4.7
 23000 -27.9 -18.2  345  23 12   7.7   4.2 | -26.9 -16.4  325  32 16   8.1   4.5
 22000 -25.6 -14.1  345  24 12   7.7   4.2 | -24.5 -12.1  320  31 16   8.1   4.5
 21000 -23.3  -9.9  340  24 13   7.5   4.1 | -22.2  -8.0  315  31 16   6.2   3.4
 20000 -21.0  -5.8  340  24 12   7.5   4.1 | -20.3  -4.5  315  30 15   6.1   3.3
 19500 -19.9  -3.8  340  23 12   7.5   4.1 | -19.4  -2.9  315  29 15   6.1   3.3
 19000 -18.8  -1.8  340  23 12   7.5   4.1 | -18.5  -1.3  315  29 15   6.1   3.3
 18500 -17.7   0.1  340  23 12   6.9   3.8 | -17.6   0.3  315  28 14   6.5   3.5
 18000 -16.7   1.9  340  23 12   6.6   3.6 | -16.6   2.1  315  29 15   6.6   3.6
 17500 -15.7   3.7  340  23 12   6.6   3.6 | -15.6   3.9  320  29 15   6.6   3.6
 17000 -14.7   5.5  340  24 12   6.6   3.6 | -14.6   5.7  320  28 15   6.3   3.5
 16500 -13.7   7.3  335  24 12   6.5   3.6 | -13.7   7.3  320  27 14   6.3   3.5
 16000 -12.7   9.1  335  24 13   7.4   4.0 | -12.2  10.0  325  25 13   6.7   3.7
 15500 -11.6  11.1  335  24 13   7.4   4.0 | -11.2  11.8  325  24 12   6.7   3.7
 15000 -10.0  14.0  335  24 13   7.0   3.8 | -10.2  13.6  325  23 12   6.6   3.6
 14500  -8.9  16.0  335  24 12   7.0   3.8 |  -9.2  15.4  330  22 11   6.5   3.6
 14000  -7.8  18.0  335  24 12   7.3   4.0 |  -8.2  17.2  330  21 11   7.5   4.1
 13500  -6.7  19.9  335  23 12   7.3   4.0 |  -7.1  19.2  335  20 10   7.5   4.1
 13000  -5.6  21.9  335  22 11   7.3   4.0 |  -6.0  21.2  335  19 10   7.8   4.3
 12500  -4.5  23.9  335  21 11   7.4   4.0 |  -4.8  23.4  340  18  9   7.8   4.3
 12000  -3.4  25.9  335  20 10   7.0   3.9 |  -3.6  25.5  340  18  9   7.4   4.1
 11500  -2.4  27.7  335  18  9   7.0   3.8 |  -2.5  27.5  340  17  9   7.4   4.0
 11000  -1.4  29.5  330  16  8   6.5   3.5 |  -1.5  29.3  340  15  8   7.1   3.9
 10500  -0.5  31.1  330  14  7   7.1   3.9 |  -0.4  31.3  340  14  7   7.8   4.3
 10250   0.0  32.0  330  13  7   3.3   1.8 |   0.1  32.2  340  14  7   3.8   2.1
 10000   0.1  32.2  330  13  7   3.5   1.9 |   0.3  32.5  340  14  7   5.2   2.8
  9750   0.6  33.1  325  12  6   7.4   4.0 |   0.9  33.6  340  13  7  10.0   5.5
  9500   1.1  34.0  320  11  6   6.7   3.7 |   1.6  34.9  340  13  7   9.0   5.0
  9250   1.6  34.9  320  10  5   5.7   3.1 |   2.3  36.1  340  12  6   8.0   4.4
  9000   1.9  35.4  315  10  5   5.2   2.8 |   2.8  37.0  335  12  6   7.5   4.1
  8750   2.4  36.3  315  10  5   7.1   3.9 |   3.4  38.1  335  12  6   9.3   5.1
  8500   3.0  37.4  315  10  5   7.6   4.2 |   4.1  39.4  335  13  7   9.5   5.2
  8250   3.5  38.3  315  10  5   7.9   4.3 |   4.8  40.6  335  13  7   9.4   5.1
  8000   4.1  39.4  315  11  6   8.1   4.5 |   5.5  41.9  330  14  7   9.0   4.9
  7750   4.8  40.6  315  12  6   9.3   5.1 |   6.2  43.2  330  15  8   9.9   5.4
  7500   5.4  41.7  315  12  6   7.9   4.3 |   6.9  44.4  325  16  8   6.4   3.5
  7250   5.9  42.6  315  14  7   4.6   2.5 |   7.0  44.6  320  18  9  -0.1  -0.0
  7000   6.2  43.2  310  17  9   4.3   2.4 |   6.9  44.4  310  20 10  -0.7  -0.4
  6750   6.5  43.7  310  19 10   3.9   2.1 |   6.8  44.2  305  23 12  -3.8  -2.1
  6500   6.3  43.3  305  21 11 -12.6  -6.9 |   6.2  43.2  300  26 13  -8.8  -4.8
  6250   4.6  40.3  295  20 10 -24.8 -13.6 |   5.5  41.9  295  22 11 -10.1  -5.6
  6000   2.9  37.2  285  19 10 -19.9 -10.9 |   4.7  40.5  290  19 10  -7.8  -4.3
  5750   1.4  34.5  275  19 10 -23.6 -12.9 |   4.1  39.4  280  16  8  -9.6  -5.3
  5500  -0.8  30.6  260  13  7 -33.6 -18.4 |   2.9  37.2  270  11  6 -21.5 -11.8

           01/24/2015 at 1400 MST          |       01/24/2015 at 1700 MST
                                           |
K index... +18.0  LI... +4.2               | K index... +10.2  LI... +4.5
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -5.6
                                           |
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 -59.4 -74.9  355  24 12   2.7   1.5 | -59.5 -75.1  005  25 13   3.2   1.8
 45000 -55.3 -67.5  005  26 14   0.9   0.5 | -54.7 -66.5  360  24 12   0.7   0.4
 40000 -56.1 -69.0  345  37 19  -0.5  -0.3 | -56.0 -68.8  355  49 25  -0.8  -0.4
 38000 -55.9 -68.6  345  44 23   1.0   0.6 | -56.4 -69.5  355  63 33  -0.4  -0.2
 36000 -55.3 -67.5  350  54 28   1.0   0.5 | -56.6 -69.9  005  84 43  -0.4  -0.2
 34000 -54.0 -65.2  350  61 31   6.1   3.3 | -55.6 -68.1  005 103 53   9.1   5.0
 32000 -50.3 -58.5  345  54 28   6.1   3.3 | -50.1 -58.2  005 102 53   9.1   5.0
 30000 -46.4 -51.5  335  48 25   8.0   4.4 | -44.8 -48.6  005 100 52   8.2   4.5
 29000 -44.0 -47.2  335  46 23   8.1   4.4 | -42.3 -44.1  005  96 50   8.2   4.5
 28000 -41.6 -42.9  335  43 22   8.1   4.4 | -39.9 -39.8  005  92 48   8.2   4.5
 27000 -39.1 -38.4  335  40 21   8.8   4.9 | -37.4 -35.3  005  88 45   7.9   4.3
 26000 -36.3 -33.3  335  41 21   9.3   5.1 | -35.1 -31.2  360  77 40   7.7   4.2
 25000 -33.6 -28.5  335  41 21   9.3   5.1 | -32.8 -27.0  355  66 34   7.7   4.2
 24000 -30.8 -23.4  335  42 22   9.1   5.0 | -30.5 -22.9  345  56 29   7.6   4.2
 23000 -28.1 -18.6  335  42 21   8.9   4.9 | -28.2 -18.8  345  54 28   7.5   4.1
 22000 -25.5 -13.9  335  41 21   8.9   4.9 | -26.0 -14.8  340  53 27   7.5   4.1
 21000 -22.8  -9.0  335  41 21   8.4   4.6 | -23.7 -10.7  340  52 27   8.8   4.8
 20000 -20.4  -4.7  335  41 21   8.3   4.5 | -21.0  -5.8  340  52 27   9.1   5.0
 19500 -19.1  -2.4  335  41 21   8.3   4.5 | -19.6  -3.3  335  51 26   9.1   5.0
 19000 -17.9  -0.2  335  41 21   8.3   4.5 | -18.2  -0.8  335  51 26   9.1   5.0
 18500 -16.7   1.9  335  40 21   7.3   4.0 | -16.9   1.6  335  51 26   8.7   4.8
 18000 -15.7   3.7  330  38 20   6.7   3.7 | -15.6   3.9  340  50 26   8.4   4.6
 17500 -14.8   5.4  330  36 19   6.6   3.6 | -14.4   6.1  340  49 25   8.4   4.6
 17000 -13.8   7.2  330  35 18   6.4   3.5 | -13.2   8.2  340  48 25   7.4   4.1
 16500 -12.4   9.7  330  33 17   6.3   3.5 | -11.5  11.3  340  46 24   7.4   4.1
 16000 -11.6  11.1  325  33 17   5.7   3.1 | -10.5  13.1  345  43 22   6.6   3.6
 15500 -10.7  12.7  325  32 17   5.8   3.2 |  -9.6  14.7  345  40 21   6.9   3.8
 15000  -9.9  14.2  325  31 16   5.4   3.0 |  -8.7  16.3  345  38 19   4.2   2.3
 14500  -9.1  15.6  325  30 15   5.5   3.0 |  -8.1  17.4  345  35 18   4.4   2.4
 14000  -8.3  17.1  325  29 15   5.0   2.8 |  -7.5  18.5  340  33 17   4.0   2.2
 13500  -7.6  18.3  320  28 14   5.0   2.7 |  -7.0  19.4  340  31 16   3.9   2.2
 13000  -6.9  19.6  320  27 14   5.4   2.9 |  -6.4  20.5  340  29 15   4.0   2.2
 12500  -6.0  21.2  320  26 14   5.5   3.0 |  -5.8  21.6  345  27 14   4.0   2.2
 12000  -5.2  22.6  320  26 13   5.7   3.1 |  -5.2  22.6  345  26 13   5.4   3.0
 11500  -4.4  24.1  320  26 13   5.8   3.2 |  -4.3  24.3  345  27 14   6.2   3.4
 11000  -3.5  25.7  320  25 13   7.1   3.9 |  -3.4  25.9  350  28 14   6.6   3.6
 10500  -2.3  27.9  320  26 13   8.4   4.6 |  -2.4  27.7  350  26 14   7.8   4.3
 10250  -1.8  28.8  320  26 13   3.9   2.1 |  -1.9  28.6  350  26 13   2.2   1.2
 10000  -1.6  29.1  325  26 13   6.6   3.6 |  -1.8  28.8  350  25 13   4.9   2.7
  9750  -0.7  30.7  325  26 13  13.0   7.2 |  -1.0  30.2  350  24 12  12.2   6.7
  9500   0.2  32.4  325  26 13  11.7   6.4 |  -0.2  31.6  350  22 12  10.7   5.9
  9250   1.1  34.0  330  26 14  10.7   5.8 |   0.6  33.1  345  21 11   9.5   5.2
  9000   1.8  35.2  330  27 14   9.8   5.4 |   1.2  34.2  340  21 11   7.3   4.0
  8750   2.7  36.9  330  27 14  11.4   6.3 |   1.8  35.2  335  21 11   8.0   4.4
  8500   3.6  38.5  330  27 14  12.0   6.6 |   2.4  36.3  330  22 11   9.4   5.2
  8250   4.4  39.9  330  27 14   9.2   5.0 |   3.0  37.4  325  23 12   4.7   2.6
  8000   5.0  41.0  325  28 14   6.5   3.6 |   3.1  37.6  315  24 13   0.4   0.2
  7750   5.5  41.9  325  28 15   5.5   3.0 |   3.2  37.8  310  26 14   1.0   0.5
  7500   5.8  42.4  320  29 15   2.7   1.5 |   3.2  37.8  305  28 14   1.0   0.6
  7250   5.9  42.6  315  29 15  -0.1  -0.1 |   3.4  38.1  300  27 14   3.0   1.6
  7000   5.8  42.4  310  29 15  -1.0  -0.5 |   3.6  38.5  300  26 13   3.2   1.8
  6750   5.7  42.3  300  28 14  -1.0  -0.6 |   3.9  39.0  300  24 12   5.2   2.9
  6500   5.6  42.1  300  26 14  -0.1  -0.0 |   4.3  39.7  300  23 12   5.8   3.2
  6250   5.6  42.1  300  23 12   0.6   0.3 |   4.7  40.5  300  21 11   3.8   2.1
  6000   5.6  42.1  300  19 10   1.5   0.8 |   5.0  41.0  300  19 10   5.6   3.1
  5750   5.7  42.3  300  16  8  -1.2  -0.7 |   5.3  41.5  300  17  9   1.0   0.5
  5500   5.2  41.4  295  11  6 -10.5  -5.8 |   4.9  40.8  300  12  6 -12.0  -6.6
________________________________________________________________________________

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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