Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 070112
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1812 MST Saturday, February 6, 2016

This forecast is for Sunday, February 7, 2016:

If the trigger temperature of 50.2 F/10.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 134 ft/min (0.7 m/s)
   Maximum height of thermals.................. 6843 ft MSL (1536 ft AGL)

Forecast maximum temperature................... 41.0 F/5.5 C
Time of trigger temperature.................... None
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................. 5665 ft MSL (358 ft AGL)
Thermal soaring outlook for Monday 02/08....... Poor

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1700 MST)......... Becoming good
Height of stable layer (12-18K ft MSL)......... 17000 ft MSL (11693 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 28700 ft MSL (23393 ft AGL)
Wave soaring outlook for Monday 02/08.......... Poor

Remarks...

Sunrise/Sunset.................... 07:01:39 / 17:24:35 MST
Total possible sunshine........... 10 hr 22 min 56 sec (622 min 56 sec)
Altitude of sun at 12:13:28 MST... 34.98 degrees

Upper air data from numerical model forecast valid on 02/07/2016 at 0500 MST

Freezing level.................. 5564 ft MSL (257 ft AGL)
Additional freezing level....... 7084 ft MSL (1777 ft AGL)
Convective condensation level... 18390 ft MSL (13083 ft AGL)
Lifted condensation level....... 12393 ft MSL (7086 ft AGL)
Lifted index.................... +12.3
K index......................... -10.6

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  -56.1 -69.0   300   40   21   2.6   1.4      M     M       M      M    M
 45000  -52.0 -61.6   300   63   32   2.1   1.1      M     M       M      M    M
 40000  -58.9 -74.0   325   72   37  -4.8  -2.6      M     M       M      M    M
 38000  -60.3 -76.5   330   78   40   1.9   1.0      M     M       M      M    M
 36000  -59.2 -74.6   325   85   44   1.8   1.0      M     M       M      M    M
 34000  -57.9 -72.2   325   91   47   6.5   3.5      M     M       M      M    M
 32000  -53.1 -63.6   330   84   43   8.0   4.4      M     M       M      M    M
 30000  -47.7 -53.9   335   78   40   8.3   4.6   27.6  81.7    16.9      M    M
 29000  -45.2 -49.4   335   78   40   8.3   4.6   27.0  80.5    16.7      M    M
 28000  -42.7 -44.9   335   77   40   8.4   4.6   26.4  79.6    16.5      M    M
 27000  -40.2 -40.4   335   77   40   8.5   4.7   26.1  78.9    16.4      M    M
 26000  -37.6 -35.7   335   74   38   8.7   4.8   25.5  77.9    16.2      M    M
 25000  -35.0 -31.0   335   71   37   8.7   4.8   25.1  77.2    16.0      M    M
 24000  -32.4 -26.3   330   69   35   8.6   4.7   24.8  76.7    16.0      M    M
 23000  -29.9 -21.8   330   66   34   8.1   4.4   24.2  75.5    15.6      M    M
 22000  -27.5 -17.5   335   64   33   8.1   4.4   23.6  74.4    15.3      M    M
 21000  -25.1 -13.2   335   61   32   7.9   4.3   23.0  73.5    15.1      M    M
 20000  -22.8  -9.0   330   50   26   7.8   4.3   22.3  72.1    14.6      M    M
 19500  -21.6  -6.9   330   45   23   7.8   4.3   22.0  71.5    14.4      M    M
 19000  -20.4  -4.7   325   39   20   7.8   4.3   21.6  71.0    14.2      M    M
 18500  -19.3  -2.7   320   34   18   7.5   4.1   21.4  70.5    14.0      M    M
 18000  -18.2  -0.8   320   34   17   7.2   3.9   20.9  69.6    13.7      M    M
 17500  -17.1   1.2   325   34   17   7.2   3.9   20.5  68.8    13.4      M    M
 17000  -16.2   2.8   320   32   16   5.5   3.0   19.9  67.7    13.0      M    M
 16500  -15.3   4.5   320   29   15   5.6   3.1   19.2  66.5    12.4      M    M
 16000  -13.9   7.0   320   27   14   7.3   4.0   18.3  65.0    11.8      M    M
 15500  -12.8   9.0   325   29   15   7.2   4.0   17.9  64.2    11.5      M    M
 15000  -11.7  10.9   325   29   15   7.0   3.8   17.5  63.4    11.1      M    M
 14500  -10.7  12.7   325   28   14   7.0   3.8   17.0  62.6    10.8      M    M
 14000   -9.6  14.7   320   27   14   7.4   4.1   16.6  61.8    10.4      M    M
 13500   -8.5  16.7   325   28   14   7.5   4.1   16.2  61.1    10.1      M    M
 13000   -7.4  18.7   325   29   15   6.6   3.6   15.8  60.4     9.8      M    M
 12500   -6.5  20.3   320   29   15   6.4   3.5   15.2  59.4     9.4      M    M
 12000   -5.5  22.1   320   30   15   6.1   3.3   14.7  58.4     8.9      M    M
 11500   -4.7  23.5   315   31   16   6.0   3.3   14.1  57.3     8.4      M    M
 11000   -3.8  25.2   315   33   17   5.2   2.9   13.4  56.2     7.8      M    M
 10500   -3.1  26.4   310   34   17   5.4   2.9   12.7  54.8     7.1      M    M
 10250   -2.7  27.1   310   35   18   3.5   1.9   12.3  54.1     6.8      M    M
 10000   -2.6  27.3   310   35   18   1.8   1.0   11.7  53.0     6.2      M    M
  9750   -2.4  27.7   310   35   18   3.2   1.8   11.1  52.0     5.7      M    M
  9500   -2.1  28.2   305   36   18   4.1   2.2   10.6  51.2     5.2      M    M
  9250   -1.8  28.8   305   36   19   2.8   1.5   10.2  50.3     4.8      M    M
  9000   -1.7  28.9   305   36   19   1.4   0.8    9.6  49.2     4.2      M    M
  8750   -1.6  29.1   305   36   18   1.3   0.7    8.9  48.0     3.5      M    M
  8500   -1.6  29.1   300   35   18   1.1   0.6    8.2  46.8     2.9      M    M
  8250   -1.5  29.3   300   34   17   2.3   1.2    7.6  45.7     2.3      M    M
  8000   -1.3  29.7   300   31   16   2.7   1.5    7.1  44.7     1.7      M    M
  7750   -1.1  30.0   295   28   14   3.5   1.9    6.5  43.8     1.2      M    M
  7500   -0.8  30.6   290   26   13   5.3   2.9    6.1  43.0     0.8      M    M
  7250   -0.4  31.3   290   23   12   6.1   3.4    5.8  42.5     0.5      M    M
  7000    0.1  32.2   285   20   10   5.9   3.2    5.5  42.0     0.2      M    M
  6750    0.6  33.1   280   17    9   7.2   4.0    5.3  41.5    -0.1    129  0.7
  6500    1.2  34.2   275   15    8   7.9   4.3    5.1  41.3    -0.2    104  0.5
  6250    1.7  35.1   265   13    7   7.2   4.0    5.0  40.9    -0.4     80  0.4
  6000    2.2  36.0   255   12    6   6.9   3.8    4.8  40.6    -0.6     57  0.3
  5750    2.2  36.0   245   11    5 -13.5  -7.4    4.0  39.2    -1.3     50  0.3
  5500   -0.1  31.8   225    8    4 -43.8 -24.0    1.0  33.9    -4.4    112  0.6

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

           02/07/2016 at 0800 MST          |       02/07/2016 at 1100 MST
                                           |
K index... -10.0  LI... +8.5               | K index... -6.0  LI... +7.6
CAPE... 0.0  CIN... -1.3                   | 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 -55.5 -67.9  305  38 20   2.0   1.1 | -55.5 -67.9  315  28 14   1.9   1.1
 45000 -52.3 -62.1  305  66 34   2.0   1.1 | -52.6 -62.7  315  47 24   2.0   1.1
 40000 -60.0 -76.0  325  71 36  -5.4  -3.0 | -59.3 -74.7  325  67 35  -4.8  -2.6
 38000 -61.5 -78.7  330  76 39   2.5   1.3 | -60.5 -76.9  325  75 39   3.0   1.7
 36000 -60.1 -76.2  325  83 43   2.4   1.3 | -58.7 -73.7  320  82 42   3.0   1.6
 34000 -58.4 -73.1  325  90 46   7.3   4.0 | -56.2 -69.2  315  88 45   8.0   4.4
 32000 -53.4 -64.1  330  90 46   8.5   4.6 | -51.6 -60.9  320  86 44   7.7   4.2
 30000 -47.6 -53.7  335  92 47   9.2   5.0 | -46.9 -52.4  325  84 43   8.1   4.4
 29000 -44.8 -48.6  335  91 47   9.2   5.1 | -44.5 -48.1  325  82 42   8.1   4.4
 28000 -42.0 -43.6  330  91 47   9.2   5.1 | -42.1 -43.8  330  81 41   8.1   4.4
 27000 -39.2 -38.6  330  91 47   9.3   5.1 | -39.7 -39.5  330  79 41   8.4   4.6
 26000 -36.5 -33.7  330  89 46   9.3   5.1 | -37.0 -34.6  330  76 39   8.8   4.9
 25000 -33.7 -28.7  330  88 45   9.3   5.1 | -34.4 -29.9  325  74 38   8.8   4.9
 24000 -30.9 -23.6  330  86 44   9.0   4.9 | -31.7 -25.1  325  72 37   8.7   4.8
 23000 -28.4 -19.1  330  83 43   8.5   4.6 | -29.2 -20.6  320  70 36   8.4   4.6
 22000 -25.8 -14.4  330  80 41   8.5   4.6 | -26.7 -16.1  320  68 35   8.4   4.6
 21000 -23.4 -10.1  330  77 39   5.8   3.2 | -24.3 -11.7  320  66 34   5.7   3.1
 20000 -22.0  -7.6  335  74 38   4.8   2.6 | -22.9  -9.2  320  62 32   4.6   2.5
 19500 -21.3  -6.3  335  73 37   4.8   2.6 | -22.2  -8.0  325  59 31   4.6   2.6
 19000 -20.6  -5.1  335  71 37   4.9   2.7 | -21.5  -6.7  325  57 29   4.8   2.6
 18500 -19.8  -3.6  340  70 36   7.0   3.8 | -20.8  -5.4  325  55 28   6.9   3.8
 18000 -18.5  -1.3  335  61 31   8.8   4.9 | -19.5  -3.1  325  52 27   8.8   4.8
 17500 -17.2   1.0  330  52 27   9.1   5.0 | -17.5   0.5  325  49 25   5.8   3.2
 17000 -16.3   2.7  325  47 24   3.5   1.9 | -17.0   1.4  325  48 25   4.2   2.3
 16500 -15.7   3.7  325  43 22   3.8   2.1 | -16.4   2.5  325  47 24   4.9   2.7
 16000 -14.5   5.9  320  37 19   6.7   3.7 | -15.3   4.5  325  45 23   7.8   4.3
 15500 -13.5   7.7  320  34 18   6.9   3.8 | -14.2   6.4  320  42 22   7.9   4.3
 15000 -12.7   9.1  320  33 17   4.5   2.5 | -13.3   8.1  320  40 21   3.5   1.9
 14500 -12.0  10.4  320  32 17   4.7   2.6 | -12.8   9.0  325  40 20   3.8   2.1
 14000 -11.2  11.8  320  32 16   5.4   3.0 | -12.1  10.2  325  39 20   5.7   3.1
 13500 -10.4  13.3  325  32 17   5.4   3.0 | -11.2  11.8  325  40 20   5.7   3.1
 13000  -9.6  14.7  325  33 17   5.7   3.1 | -10.4  13.3  330  40 20   5.3   2.9
 12500  -8.7  16.3  320  35 18   5.7   3.1 |  -9.6  14.7  330  39 20   5.2   2.9
 12000  -7.9  17.8  320  36 19   5.1   2.8 |  -8.8  16.2  330  39 20   5.8   3.2
 11500  -7.2  19.0  320  38 20   5.0   2.7 |  -7.9  17.8  330  36 18   5.9   3.2
 11000  -6.5  20.3  315  40 20   3.4   1.8 |  -7.1  19.2  330  34 18   5.7   3.1
 10500  -6.1  21.0  315  40 21   3.3   1.8 |  -6.2  20.8  330  35 18   6.0   3.3
 10250  -5.8  21.6  315  40 21   2.0   1.1 |  -5.8  21.6  330  35 18   4.3   2.4
 10000  -5.8  21.6  315  40 20   0.9   0.5 |  -5.6  21.9  330  34 17   2.9   1.6
  9750  -5.6  21.9  315  39 20   2.9   1.6 |  -5.3  22.5  325  32 17   4.6   2.5
  9500  -5.4  22.3  310  39 20   4.0   2.2 |  -4.9  23.2  325  32 16   5.1   2.8
  9250  -5.1  22.8  310  38 20   3.0   1.6 |  -4.6  23.7  320  31 16   3.8   2.1
  9000  -5.0  23.0  310  37 19   2.1   1.2 |  -4.4  24.1  320  30 16   3.2   1.8
  8750  -4.8  23.4  310  35 18   3.6   2.0 |  -4.1  24.6  320  30 15   3.1   1.7
  8500  -4.5  23.9  310  32 17   4.8   2.7 |  -3.9  25.0  315  29 15   3.5   1.9
  8250  -4.1  24.6  310  30 16   5.1   2.8 |  -3.6  25.5  315  27 14   4.6   2.5
  8000  -3.8  25.2  310  28 14   4.9   2.7 |  -3.3  26.1  315  25 13   4.5   2.5
  7750  -3.4  25.9  310  26 13   6.4   3.5 |  -3.0  26.6  315  23 12   5.4   2.9
  7500  -2.8  27.0  310  24 12   7.5   4.1 |  -2.5  27.5  315  21 11   7.4   4.0
  7250  -2.3  27.9  310  22 11   6.8   3.7 |  -1.9  28.6  320  19 10   7.8   4.3
  7000  -1.8  28.8  315  20 10   7.0   3.8 |  -1.4  29.5  320  18  9   8.1   4.4
  6750  -1.3  29.7  315  18  9   6.9   3.8 |  -0.8  30.6  320  16  8   6.5   3.6
  6500  -0.8  30.6  315  16  8   6.7   3.7 |  -0.4  31.3  320  15  7   5.5   3.0
  6250  -0.3  31.5  310  14  7   7.5   4.1 |   0.1  32.2  320  12  6   7.7   4.2
  6000   0.3  32.5  310  13  6   4.7   2.6 |   0.6  33.1  315  10  5   3.4   1.9
  5750   0.0  32.0  305  10  5 -15.1  -8.3 |   0.5  32.9  310   8  4  -3.5  -1.9
  5500  -2.1  28.2  280   6  3 -39.2 -21.5 |   0.1  32.2  295   4  2  -3.2  -1.8

           02/07/2016 at 1400 MST          |       02/07/2016 at 1700 MST
                                           |
K index... +0.8  LI... +7.3                | K index... +1.8  LI... +9.3
CAPE... 0.0  CIN... -1.3                   | CAPE... 0.0  CIN... -0.6
                                           |
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 -55.4 -67.7  305  30 16   2.0   1.1 | -56.4 -69.5  310  32 17   1.0   0.5
 45000 -52.4 -62.3  305  44 22   1.4   0.8 | -55.0 -67.0  315  45 23   0.5   0.3
 40000 -57.3 -71.1  325  67 35  -3.4  -1.9 | -56.4 -69.5  335  76 39  -1.0  -0.5
 38000 -58.1 -72.6  330  74 38   2.1   1.2 | -56.8 -70.2  340  84 43  -0.1  -0.0
 36000 -56.8 -70.2  330  73 38   2.1   1.1 | -56.8 -70.2  340  84 43  -0.1  -0.0
 34000 -55.1 -67.2  330  73 37   5.6   3.1 | -56.2 -69.2  345  86 44   6.5   3.6
 32000 -51.9 -61.4  335  69 36   5.4   2.9 | -52.5 -62.5  350  95 49   6.2   3.4
 30000 -48.3 -54.9  335  67 35   8.3   4.6 | -48.4 -55.1  355 101 52   8.9   4.9
 29000 -45.8 -50.4  330  69 36   8.3   4.5 | -45.7 -50.3  355  97 50   8.9   4.9
 28000 -43.3 -45.9  330  71 37   8.3   4.6 | -43.0 -45.4  355  93 48   9.0   4.9
 27000 -40.8 -41.4  330  73 37   9.0   4.9 | -40.3 -40.5  355  89 46   8.9   4.9
 26000 -37.9 -36.2  330  73 38   9.7   5.3 | -37.7 -35.9  350  87 45   8.9   4.9
 25000 -35.1 -31.2  330  74 38   9.7   5.3 | -35.0 -31.0  350  85 44   8.9   4.9
 24000 -32.2 -26.0  330  74 38   9.5   5.2 | -32.3 -26.1  350  82 42   9.0   4.9
 23000 -29.4 -20.9  330  73 38   9.1   5.0 | -29.6 -21.3  345  81 42   9.1   5.0
 22000 -26.7 -16.1  330  71 37   9.1   5.0 | -26.9 -16.4  340  80 41   9.1   5.0
 21000 -24.1 -11.4  330  70 36   6.5   3.6 | -24.2 -11.6  340  79 41   8.1   4.4
 20000 -22.4  -8.3  330  69 35   5.8   3.2 | -21.9  -7.4  340  76 39   7.9   4.4
 19500 -21.5  -6.7  330  68 35   5.8   3.2 | -20.7  -5.3  340  75 38   7.9   4.4
 19000 -20.7  -5.3  335  68 35   5.8   3.2 | -19.5  -3.1  340  73 38   8.0   4.4
 18500 -19.8  -3.6  335  67 35   5.8   3.2 | -18.3  -0.9  340  72 37   6.8   3.7
 18000 -18.9  -2.0  335  65 33   5.9   3.2 | -17.4   0.7  340  70 36   6.2   3.4
 17500 -18.1  -0.6  335  62 32   5.9   3.2 | -16.5   2.3  340  69 35   6.0   3.3
 17000 -16.7   1.9  330  59 30   6.1   3.4 | -15.4   4.3  335  64 33   4.8   2.6
 16500 -15.8   3.6  330  58 30   6.1   3.4 | -14.7   5.5  335  60 31   4.4   2.4
 16000 -14.9   5.2  330  56 29   6.1   3.4 | -14.2   6.4  335  57 29   3.4   1.9
 15500 -14.0   6.8  330  54 28   6.1   3.3 | -13.7   7.3  330  55 28   3.4   1.9
 15000 -12.9   8.8  325  51 26   7.5   4.1 | -12.9   8.8  330  51 26   6.8   3.7
 14500 -11.8  10.8  325  47 24   7.6   4.2 | -11.9  10.6  325  46 24   6.9   3.8
 14000 -10.9  12.4  325  44 23   4.8   2.6 | -11.2  11.8  325  44 22   2.7   1.5
 13500 -10.2  13.6  325  43 22   4.8   2.6 | -10.7  12.7  330  44 23   2.8   1.5
 13000  -9.5  14.9  325  42 22   4.7   2.6 | -10.2  13.6  330  44 23   4.8   2.6
 12500  -8.8  16.2  325  41 21   4.6   2.5 |  -9.4  15.1  330  42 22   4.9   2.7
 12000  -8.0  17.6  325  40 20   5.6   3.1 |  -8.8  16.2  330  39 20   4.3   2.4
 11500  -7.2  19.0  325  37 19   5.8   3.2 |  -8.1  17.4  325  35 18   4.2   2.3
 11000  -6.4  20.5  320  35 18   4.2   2.3 |  -7.5  18.5  325  32 17   5.4   2.9
 10500  -5.8  21.6  320  34 17   4.2   2.3 |  -6.7  19.9  325  31 16   5.6   3.1
 10250  -5.5  22.1  320  33 17   3.7   2.0 |  -6.3  20.7  325  30 16   4.5   2.5
 10000  -5.3  22.5  320  32 17   3.8   2.1 |  -6.0  21.2  320  29 15   4.0   2.2
  9750  -4.9  23.2  315  31 16   5.4   2.9 |  -5.6  21.9  320  28 14   6.1   3.3
  9500  -4.5  23.9  315  30 15   6.1   3.3 |  -5.1  22.8  320  27 14   6.6   3.6
  9250  -4.1  24.6  315  29 15   3.7   2.0 |  -4.7  23.5  315  27 14   4.8   2.6
  9000  -3.9  25.0  310  27 14   2.1   1.1 |  -4.4  24.1  315  25 13   3.4   1.9
  8750  -3.8  25.2  310  26 13   3.1   1.7 |  -4.1  24.6  315  24 12   5.9   3.2
  8500  -3.5  25.7  310  24 12   3.6   2.0 |  -3.7  25.3  315  22 11   5.7   3.2
  8250  -3.3  26.1  310  21 11   3.7   2.0 |  -3.4  25.9  315  20 10   2.9   1.6
  8000  -3.0  26.6  315  18  9   3.5   1.9 |  -3.2  26.2  315  18  9   2.9   1.6
  7750  -2.7  27.1  315  16  8   4.4   2.4 |  -2.9  26.8  315  15  8   3.2   1.7
  7500  -2.4  27.7  325  13  6   5.3   2.9 |  -2.7  27.1  320  12  6   4.1   2.2
  7250  -2.0  28.4  330  10  5   5.0   2.7 |  -2.4  27.7  320  10  5   4.5   2.5
  7000  -1.6  29.1  345   8  4   5.0   2.7 |  -2.0  28.4  320   7  4   4.2   2.3
  6750  -1.2  29.8  360   7  4   5.4   3.0 |  -1.7  28.9  320   5  2   5.0   2.8
  6500  -0.8  30.6  020   6  3   5.9   3.2 |  -1.3  29.7  330   3  2   6.1   3.3
  6250  -0.4  31.3  035   6  3   6.0   3.3 |  -0.8  30.6  350   1  1   5.9   3.2
  6000   0.1  32.2  050   6  3   5.2   2.9 |  -0.4  31.3  080   1  1   6.7   3.7
  5750   0.3  32.5  065   4  2   2.7   1.5 |   0.0  32.0  155   2  1   2.7   1.5
  5500   0.3  32.5  090   2  1   1.4   0.7 |  -0.2  31.6  185   2  1  -6.4  -3.5
________________________________________________________________________________

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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