Soaring Guidance
Issued by NWS Denver/Boulder, CO

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919
UXUS97 KBOU 081258
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0558 MST Monday, February 8, 2016

This forecast is for Monday, February 8, 2016:

If the trigger temperature of 49.8 F/9.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 129 ft/min (0.7 m/s)
   Maximum height of thermals.................. 8764 ft MSL (3479 ft AGL)

Forecast maximum temperature................... 49.0 F/9.9 C
Time of trigger temperature.................... 1415 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7180 ft MSL (1895 ft AGL)
Thermal soaring outlook for Tuesday 02/09...... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 13665 ft MSL (8380 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 14651 ft MSL (9366 ft AGL)
Wave soaring outlook for Tuesday 02/09......... Poor

Remarks...

Sunrise/Sunset.................... 07:00:34 / 17:25:46 MST
Total possible sunshine........... 10 hr 25 min 13 sec (625 min 13 sec)
Altitude of sun at 12:13:31 MST... 35.29 degrees

Upper air data from rawinsonde observation taken on 02/08/2016 at 0500 MST

Freezing level.................. 6736 ft MSL (1451 ft AGL)
Additional freezing level....... 8115 ft MSL (2830 ft AGL)
Convective condensation level... 17930 ft MSL (12645 ft AGL)
Lifted condensation level....... 13504 ft MSL (8219 ft AGL)
Lifted index.................... +9.6
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  -57.0 -70.6   325   57   30   4.9   2.7  106.0 222.7    55.0      M    M
 45000  -56.0 -68.8   325   64   33   2.8   1.5   83.0 181.3    44.8      M    M
 40000  -55.3 -67.5   340   57   29   0.7   0.4   60.6 141.1    33.4      M    M
 38000  -62.5 -80.5   340   81   41   3.9   2.2   40.9 105.6    21.1      M    M
 36000  -60.7 -77.3   340   88   45   7.0   3.9   34.9  94.8    17.6      M    M
 34000  -56.3 -69.3   345   82   42   8.0   4.4   32.9  91.2    16.6      M    M
 32000  -50.8 -59.4   350   91   47   9.2   5.0   31.3  88.4    16.0      M    M
 30000  -45.4 -49.7   355   98   50   8.3   4.5   30.7  87.2    15.9      M    M
 29000  -43.0 -45.4   355   91   47   8.2   4.5   30.0  85.9    15.6      M    M
 28000  -40.5 -40.9   355   85   44   8.2   4.5   29.4  84.9    15.3      M    M
 27000  -38.0 -36.4   350   78   40   9.1   5.0   29.0  84.1    15.2      M    M
 26000  -35.2 -31.4   350   72   37   9.4   5.2   28.9  83.9    15.3      M    M
 25000  -32.7 -26.9   345   73   38   4.8   2.6   28.3  82.9    15.0      M    M
 24000  -31.1 -24.0   350   71   37   6.0   3.3   26.6  79.9    13.9      M    M
 23000  -29.1 -20.4   350   72   37   6.8   3.7   25.4  77.8    13.0      M    M
 22000  -27.1 -16.8   345   73   38   6.7   3.7   24.4  75.9    12.3      M    M
 21000  -24.8 -12.6   345   74   38   8.0   4.4   23.6  74.5    11.8      M    M
 20000  -22.4  -8.3   345   75   39   8.0   4.4   23.1  73.5    11.4      M    M
 19500  -21.2  -6.2   345   73   37   8.0   4.4   22.7  72.9    11.2      M    M
 19000  -20.0  -4.0   345   70   36   8.0   4.4   22.4  72.3    11.0      M    M
 18500  -18.8  -1.8   345   68   35   8.8   4.8   22.1  71.9    10.8      M    M
 18000  -17.5   0.5   345   67   35   7.9   4.4   22.0  71.6    10.8      M    M
 17500  -16.4   2.5   345   67   34   7.1   3.9   21.5  70.7    10.4      M    M
 17000  -15.4   4.3   340   66   34   7.0   3.8   21.0  69.8    10.0      M    M
 16500  -14.4   6.1   340   66   34   7.0   3.8   20.6  69.0     9.6      M    M
 16000  -12.8   9.0   340   65   34   7.1   3.9   19.9  67.8     9.1      M    M
 15500  -11.7  10.9   340   66   34   7.1   3.9   19.4  67.0     8.7      M    M
 15000  -10.7  12.7   340   67   35   7.1   3.9   19.0  66.1     8.3      M    M
 14500   -9.6  14.7   340   68   35   6.9   3.8   18.5  65.4     8.0      M    M
 14000   -8.6  16.5   340   68   35   3.6   2.0   18.1  64.6     7.6      M    M
 13500   -9.1  15.6   335   60   31  -2.4  -1.3   16.0  60.8     5.7      M    M
 13000   -9.0  15.8   335   52   27   0.5   0.3   14.5  58.1     4.4      M    M
 12500   -8.8  16.2   330   44   23   4.5   2.5   13.1  55.7     3.1      M    M
 12000   -7.8  18.0   325   38   19   6.6   3.6   12.7  54.8     2.7      M    M
 11500   -6.8  19.8   325   36   18   6.7   3.7   12.1  53.8     2.2      M    M
 11000   -5.8  21.6   320   34   17   6.7   3.7   11.6  53.0     1.8      M    M
 10500   -4.8  23.4   320   32   16   6.7   3.7   11.2  52.1     1.3      M    M
 10250   -4.3  24.3   320   31   16   7.0   3.9   11.0  51.7     1.1      M    M
 10000   -3.7  25.3   320   29   15   7.4   4.0   10.7  51.3     0.9      M    M
  9750   -3.2  26.2   315   28   14   7.3   4.0   10.6  51.0     0.7      M    M
  9500   -2.6  27.3   315   26   13   7.3   4.0   10.4  50.6     0.5      M    M
  9250   -2.1  28.2   310   24   13   7.3   4.0   10.2  50.3     0.4      M    M
  9000   -1.5  29.3   310   23   12   7.3   4.0   10.0  50.0     0.2      M    M
  8750   -1.0  30.2   310   23   12   6.1   3.4    9.8  49.6    -0.0    226  1.2
  8500   -0.6  30.9   305   23   12   5.2   2.9    9.4  49.0    -0.4    207  1.1
  8250   -0.2  31.6   305   23   12   5.6   3.0    9.1  48.4    -0.7    187  1.0
  8000    0.2  32.4   305   23   12   5.1   2.8    8.8  47.8    -1.0    168  0.9
  7750    0.6  33.1   300   21   11   6.5   3.6    8.4  47.2    -1.3    148  0.8
  7500    1.0  33.8   300   19   10   1.1   0.6    8.1  46.6    -1.7    129  0.7
  7250    0.7  33.3   295   18    9  -5.2  -2.9    7.1  44.7    -2.7    130  0.7
  7000    0.5  32.9   290   16    8  -1.1  -0.6    6.1  42.9    -3.7    130  0.7
  6750    0.2  32.4   280   11    6 -12.6  -6.9    5.0  41.0    -4.7    132  0.7
  6500   -1.3  29.7   255    7    4 -19.5 -10.7    2.8  37.0    -6.9    168  0.9
  6250   -2.2  28.0   205    6    3  -4.8  -2.7    1.1  34.0    -8.6    187  1.0
  6000   -2.4  27.7   170   10    5  -5.0  -2.8    0.2  32.3    -9.5    185  0.9
  5750   -3.3  26.1   170    9    5 -20.0 -11.0   -1.5  29.3   -11.2    206  1.0
  5500   -5.0  23.0   175    8    4 -20.7 -11.3   -4.0  24.9   -13.7    251  1.3

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

           02/08/2016 at 0800 MST          |       02/08/2016 at 1100 MST
                                           |
K index... +6.0  LI... +6.8                | K index... +6.9  LI... +7.5
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.5
                                           |
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 -56.3 -69.3  340  38 20   1.4   0.8 | -57.4 -71.3  335  46 24   1.7   1.0
 45000 -54.3 -65.7  340  55 28  -0.9  -0.5 | -54.8 -66.6  335  51 26  -0.5  -0.3
 40000 -61.4 -78.5  350  79 41  -4.8  -2.6 | -62.9 -81.2  350  79 41  -5.3  -2.9
 38000 -61.9 -79.4  355  86 44   3.9   2.2 | -62.5 -80.5  355  86 44   5.1   2.8
 36000 -59.2 -74.6  355  89 46   3.9   2.1 | -59.5 -75.1  360  90 46   5.1   2.8
 34000 -55.9 -68.6  355  90 46   9.4   5.2 | -55.8 -68.4  005  92 47   9.3   5.1
 32000 -50.2 -58.4  350  83 43   9.6   5.2 | -50.1 -58.2  360  87 45   9.4   5.2
 30000 -44.6 -48.3  345  77 40   8.5   4.7 | -43.9 -47.0  355  80 41   9.1   5.0
 29000 -42.1 -43.8  345  75 38   8.5   4.7 | -41.1 -42.0  355  76 39   9.1   5.0
 28000 -39.5 -39.1  345  72 37   8.5   4.7 | -38.4 -37.1  350  72 37   9.1   5.0
 27000 -37.0 -34.6  345  69 36   8.2   4.5 | -35.9 -32.6  350  69 36   7.2   4.0
 26000 -34.5 -30.1  345  69 35   8.2   4.5 | -33.6 -28.5  345  67 34   7.4   4.1
 25000 -32.1 -25.8  345  68 35   8.2   4.5 | -31.4 -24.5  345  64 33   7.4   4.1
 24000 -29.6 -21.3  350  67 35   7.4   4.1 | -29.2 -20.6  345  62 32   7.5   4.1
 23000 -27.5 -17.5  350  64 33   6.9   3.8 | -27.0 -16.6  345  57 29   7.5   4.1
 22000 -25.5 -13.9  350  62 32   6.9   3.8 | -24.7 -12.5  340  53 27   7.5   4.1
 21000 -23.4 -10.1  350  59 30   6.9   3.8 | -22.6  -8.7  340  50 26   6.7   3.7
 20000 -21.4  -6.5  350  59 30   6.9   3.8 | -20.6  -5.1  340  51 26   6.8   3.7
 19500 -20.3  -4.5  345  58 30   6.9   3.8 | -19.6  -3.3  345  52 27   6.8   3.7
 19000 -19.3  -2.7  345  58 30   6.9   3.8 | -18.6  -1.5  345  53 27   7.0   3.8
 18500 -17.8  -0.0  345  58 30   6.5   3.6 | -17.7   0.1  345  53 27   5.1   2.8
 18000 -16.9   1.6  345  58 30   6.5   3.6 | -16.9   1.6  345  53 27   5.3   2.9
 17500 -15.9   3.4  345  58 30   6.6   3.6 | -16.1   3.0  345  53 27   5.8   3.2
 17000 -14.9   5.2  345  58 30   6.6   3.6 | -15.2   4.6  345  53 27   6.3   3.4
 16500 -13.9   7.0  345  58 30   6.4   3.5 | -14.3   6.3  345  53 27   6.3   3.5
 16000 -13.0   8.6  345  58 30   6.2   3.4 | -13.3   8.1  345  53 27   6.5   3.6
 15500 -12.1  10.2  345  57 29   6.1   3.4 | -11.9  10.6  345  52 27   6.3   3.4
 15000 -11.2  11.8  345  57 29   5.8   3.2 | -11.0  12.2  345  52 27   6.0   3.3
 14500 -10.4  13.3  345  56 29   5.9   3.2 | -10.2  13.6  345  51 26   5.8   3.2
 14000  -9.6  14.7  345  56 29   4.3   2.4 |  -9.4  15.1  345  51 26   4.5   2.5
 13500  -9.0  15.8  345  55 28   4.6   2.5 |  -8.7  16.3  345  50 26   4.6   2.5
 13000  -8.4  16.9  345  55 28   3.3   1.8 |  -8.2  17.2  345  49 25   3.3   1.8
 12500  -7.9  17.8  345  54 28   3.2   1.8 |  -7.7  18.1  345  49 25   3.4   1.9
 12000  -7.3  18.9  345  54 28   4.5   2.5 |  -7.2  19.0  350  48 25   3.6   1.9
 11500  -6.6  20.1  345  53 27   4.2   2.3 |  -6.6  20.1  350  47 24   3.6   2.0
 11000  -5.8  21.6  345  52 27   7.0   3.8 |  -5.9  21.4  350  46 24   5.6   3.1
 10500  -4.8  23.4  345  51 26   6.8   3.7 |  -5.1  22.8  350  46 24   5.5   3.0
 10250  -4.4  24.1  345  50 26   4.9   2.7 |  -4.7  23.5  350  46 24   5.6   3.1
 10000  -4.1  24.6  345  48 25   4.1   2.3 |  -4.3  24.3  350  46 24   6.4   3.5
  9750  -3.7  25.3  345  46 24   6.1   3.4 |  -3.7  25.3  350  45 23   8.6   4.7
  9500  -3.2  26.2  345  42 22   6.1   3.4 |  -3.1  26.4  345  44 22   7.5   4.1
  9250  -2.8  27.0  345  39 20   4.6   2.6 |  -2.7  27.1  345  41 21   5.0   2.7
  9000  -2.5  27.5  340  36 19   4.0   2.2 |  -2.3  27.9  345  39 20   4.9   2.7
  8750  -2.2  28.0  340  34 17   5.6   3.0 |  -1.9  28.6  345  36 19   6.7   3.7
  8500  -1.7  28.9  340  30 16   5.9   3.2 |  -1.3  29.7  345  33 17   6.4   3.5
  8250  -1.3  29.7  335  29 15   4.9   2.7 |  -0.9  30.4  340  30 15   5.0   2.7
  8000  -0.9  30.4  330  28 14   4.9   2.7 |  -0.6  30.9  340  27 14   4.9   2.7
  7750  -0.6  30.9  330  26 14   5.7   3.1 |  -0.2  31.6  340  24 12   6.5   3.6
  7500  -0.1  31.8  325  26 13   4.1   2.3 |   0.4  32.7  335  22 11   6.5   3.6
  7250   0.0  32.0  325  25 13   2.1   1.1 |   0.8  33.4  330  21 11   4.9   2.7
  7000   0.2  32.4  320  24 12   2.6   1.4 |   1.1  34.0  325  21 11   5.1   2.8
  6750   0.4  32.7  315  23 12   3.3   1.8 |   1.5  34.7  325  20 10   3.4   1.8
  6500   0.7  33.3  320  21 11   3.2   1.7 |   1.7  35.1  320  18  9   2.2   1.2
  6250   0.9  33.6  320  18  9   4.0   2.2 |   1.8  35.2  320  16  8   3.4   1.9
  6000   1.1  34.0  320  15  8  -1.1  -0.6 |   2.0  35.6  320  14  7  -0.0  -0.0
  5750   0.4  32.7  315  11  6 -22.2 -12.2 |   1.7  35.1  315  10  5  -8.0  -4.4
  5500  -2.1  28.2  290   5  3 -41.3 -22.7 |   0.8  33.4  305   4  2 -11.3  -6.2

           02/08/2016 at 1400 MST          |       02/08/2016 at 1700 MST
                                           |
K index... +7.3  LI... +6.6                | K index... +3.2  LI... +7.6
CAPE... 0.0  CIN... -1.3                   | CAPE... 0.0  CIN... -0.1
                                           |
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  340  46 24   0.6   0.3 | -57.4 -71.3  340  47 24   1.6   0.9
 45000 -56.3 -69.3  340  51 26  -1.0  -0.5 | -55.0 -67.0  340  51 26  -1.0  -0.6
 40000 -62.8 -81.0  350  74 38  -4.2  -2.3 | -65.0 -85.0  355  81 42  -6.6  -3.6
 38000 -61.9 -79.4  350  78 40   5.6   3.1 | -63.8 -82.8  355  84 43   7.9   4.3
 36000 -58.6 -73.5  350  77 40   5.6   3.1 | -59.1 -74.4  355  81 42   7.9   4.3
 34000 -54.8 -66.6  355  77 39   8.4   4.6 | -54.2 -65.6  355  78 40   8.8   4.8
 32000 -49.7 -57.5  005  79 41   8.5   4.7 | -48.9 -56.0  360  75 38   8.8   4.8
 30000 -43.8 -46.8  010  81 42   9.2   5.1 | -43.7 -46.7  360  72 37   8.7   4.8
 29000 -41.0 -41.8  010  80 41   9.2   5.0 | -40.4 -40.7  005  71 36   8.7   4.8
 28000 -38.2 -36.8  010  79 41   9.2   5.0 | -37.8 -36.0  005  70 36   8.7   4.8
 27000 -35.5 -31.9  005  76 39   9.1   5.0 | -35.2 -31.4  005  67 34   9.0   4.9
 26000 -32.8 -27.0  360  67 35   9.1   5.0 | -32.5 -26.5  005  60 31   8.9   4.9
 25000 -30.1 -22.2  355  60 31   9.1   5.0 | -29.8 -21.6  360  54 28   9.0   4.9
 24000 -27.4 -17.3  350  52 27   7.6   4.2 | -27.3 -17.1  350  50 26   7.0   3.9
 23000 -25.1 -13.2  340  44 22   7.6   4.2 | -25.1 -13.2  345  48 25   7.1   3.9
 22000 -22.9  -9.2  325  37 19   7.6   4.2 | -23.0  -9.4  340  47 24   7.1   3.9
 21000 -20.9  -5.6  320  35 18   4.6   2.5 | -21.0  -5.8  340  47 24   6.2   3.4
 20000 -19.5  -3.1  330  42 21   4.8   2.7 | -19.1  -2.4  340  49 25   6.3   3.5
 19500 -18.7  -1.7  335  45 23   4.9   2.7 | -18.2  -0.8  345  51 26   6.4   3.5
 19000 -18.0  -0.4  340  49 25   4.8   2.6 | -17.2   1.0  345  52 27   6.7   3.7
 18500 -17.3   0.9  340  52 27   5.6   3.1 | -16.6   2.1  345  53 27   2.8   1.5
 18000 -16.5   2.3  345  53 27   5.6   3.1 | -16.1   3.0  350  55 28   3.2   1.7
 17500 -15.6   3.9  345  53 28   5.6   3.1 | -15.7   3.7  350  56 29   3.8   2.1
 17000 -14.8   5.4  345  53 27   5.6   3.1 | -15.0   5.0  350  56 29   4.3   2.4
 16500 -14.0   6.8  345  53 27   5.6   3.1 | -14.4   6.1  350  55 28   4.6   2.5
 16000 -13.2   8.2  345  53 27   5.9   3.2 | -13.5   7.7  350  54 28   7.1   3.9
 15500 -11.9  10.6  350  52 27   5.9   3.2 | -11.9  10.6  350  50 26   6.4   3.5
 15000 -11.0  12.2  350  51 26   5.9   3.2 | -11.1  12.0  350  50 26   5.7   3.1
 14500 -10.1  13.8  350  51 26   5.9   3.2 | -10.2  13.6  350  51 26   5.7   3.1
 14000  -9.3  15.3  350  50 26   5.5   3.0 |  -9.4  15.1  350  50 26   5.4   3.0
 13500  -8.5  16.7  350  49 25   5.6   3.0 |  -8.6  16.5  350  49 25   5.4   3.0
 13000  -7.7  18.1  350  48 25   4.9   2.7 |  -8.0  17.6  350  48 25   3.6   2.0
 12500  -7.0  19.4  350  47 24   4.9   2.7 |  -7.5  18.5  350  47 24   3.7   2.1
 12000  -6.3  20.7  350  46 24   4.6   2.5 |  -6.9  19.6  350  45 23   4.4   2.4
 11500  -5.6  21.9  350  45 23   4.6   2.5 |  -6.3  20.7  350  43 22   4.4   2.4
 11000  -4.8  23.4  350  44 23   6.5   3.6 |  -5.5  22.1  350  42 21   6.7   3.7
 10500  -3.8  25.2  350  43 22   6.3   3.5 |  -4.5  23.9  350  40 20   6.7   3.7
 10250  -3.4  25.9  350  42 22   5.7   3.1 |  -4.0  24.8  350  39 20   6.5   3.5
 10000  -3.0  26.6  350  42 22   6.7   3.7 |  -3.5  25.7  350  39 20   8.0   4.4
  9750  -2.4  27.7  345  40 21   8.9   4.9 |  -2.8  27.0  345  38 20  11.0   6.0
  9500  -1.7  28.9  345  38 19   7.8   4.3 |  -2.0  28.4  345  37 19   9.3   5.1
  9250  -1.3  29.7  345  35 18   5.7   3.1 |  -1.4  29.5  345  36 18   6.3   3.4
  9000  -0.9  30.4  340  33 17   5.5   3.0 |  -1.0  30.2  345  34 17   6.3   3.5
  8750  -0.4  31.3  340  30 15   7.3   4.0 |  -0.5  31.1  340  31 16   8.4   4.6
  8500   0.2  32.4  335  27 14   6.9   3.8 |   0.2  32.4  340  28 15   7.7   4.2
  8250   0.6  33.1  335  25 13   5.6   3.1 |   0.6  33.1  340  26 14   5.9   3.2
  8000   1.0  33.8  330  23 12   5.8   3.2 |   1.1  34.0  335  24 12   6.3   3.4
  7750   1.5  34.7  325  21 11   7.0   3.8 |   1.6  34.9  335  22 11   8.0   4.4
  7500   2.0  35.6  325  19 10   7.2   3.9 |   2.2  36.0  330  20 10   8.1   4.5
  7250   2.5  36.5  325  18  9   6.2   3.4 |   2.8  37.0  330  19 10   6.6   3.6
  7000   3.0  37.4  325  17  9   6.3   3.5 |   3.3  37.9  325  18  9   7.4   4.1
  6750   3.4  38.1  320  16  8   4.7   2.6 |   3.8  38.8  325  16  8   6.2   3.4
  6500   3.7  38.7  325  14  7   3.4   1.9 |   4.2  39.6  325  15  8   4.6   2.5
  6250   4.0  39.2  325  12  6   5.4   2.9 |   4.6  40.3  320  13  7   6.1   3.3
  6000   4.3  39.7  325  10  5  -0.6  -0.3 |   5.0  41.0  320  12  6   1.7   1.0
  5750   3.7  38.7  315   6  3 -13.7  -7.5 |   4.5  40.1  310   9  5 -13.1  -7.2
  5500   2.3  36.1  280   2  1 -17.8  -9.8 |   3.0  37.4  280   5  3 -24.9 -13.7
________________________________________________________________________________

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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