Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 230105
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1905 MDT Sunday, October 22, 2017

This forecast is for Monday, October 23, 2017:

If the trigger temperature of 60.5 F/15.8 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 305 ft/min (1.5 m/s)
   Maximum height of thermals.................. 9720 ft MSL (4413 ft AGL)

Forecast maximum temperature................... 62.0 F/17.1 C
Time of trigger temperature.................... 1330 MDT
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................. 8259 ft MSL (2952 ft AGL)
Thermal soaring outlook for Tuesday 10/24...... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 40059 ft MSL (34752 ft AGL)
Wave soaring outlook for Tuesday 10/24......... Fair

Remarks...

Sunrise/Sunset.................... 07:18:38 / 18:09:49 MDT
Total possible sunshine........... 10 hr 51 min 10 sec (651 min 10 sec)
Altitude of sun at 12:43:49 MDT... 38.59 degrees

Upper air data from numerical model forecast valid on 10/23/2017 at 0600 MDT

Freezing level.................. 11865 ft MSL (6558 ft AGL)
Convective condensation level... 17874 ft MSL (12567 ft AGL)
Lifted condensation level....... 13070 ft MSL (7763 ft AGL)
Lifted index.................... +8.9
K index......................... +3.9

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  -63.6 -82.5   300   53   27   0.4   0.2      M     M       M      M    M
 45000  -62.9 -81.2   300   76   39   1.4   0.7      M     M       M      M    M
 40000  -60.9 -77.6   300   92   47   1.1   0.6      M     M       M      M    M
 38000  -57.2 -71.0   305   88   45   6.6   3.6      M     M       M      M    M
 36000  -53.3 -63.9   315   85   44   6.6   3.6      M     M       M      M    M
 34000  -47.8 -54.0   320   84   43   9.2   5.0      M     M       M      M    M
 32000  -42.3 -44.1   315   83   43   9.2   5.0      M     M       M      M    M
 30000  -36.8 -34.2   310   82   42   9.2   5.1   39.2 102.5    17.0      M    M
 29000  -34.0 -29.2   310   81   42   9.2   5.1   39.0 102.2    17.1      M    M
 28000  -31.3 -24.3   310   80   41   9.3   5.1   38.9 102.0    17.2      M    M
 27000  -28.7 -19.7   310   76   39   8.4   4.6   38.4 101.1    17.0      M    M
 26000  -26.1 -15.0   305   71   36   8.4   4.6   37.9 100.1    16.8      M    M
 25000  -23.6 -10.5   305   65   34   8.4   4.6   37.4  99.4    16.7      M    M
 24000  -21.3  -6.3   305   63   32   6.9   3.8   36.6  97.9    16.2      M    M
 23000  -19.3  -2.7   310   62   32   6.9   3.8   35.5  95.9    15.5      M    M
 22000  -17.2   1.0   315   62   32   6.9   3.8   34.5  94.1    14.8      M    M
 21000  -15.1   4.8   315   62   32   6.9   3.8   33.5  92.3    14.1      M    M
 20000  -13.1   8.4   315   60   31   6.9   3.8   32.5  90.4    13.4      M    M
 19500  -12.0  10.4   315   59   31   6.9   3.8   32.0  89.6    13.0      M    M
 19000  -11.0  12.2   315   58   30   6.6   3.6   31.6  88.8    12.7      M    M
 18500  -10.1  13.8   315   57   29   6.0   3.3   30.9  87.6    12.2      M    M
 18000   -8.8  16.2   315   55   28   5.9   3.2   30.0  85.9    11.4      M    M
 17500   -8.0  17.6   315   53   27   5.7   3.1   29.2  84.6    10.9      M    M
 17000   -7.1  19.2   315   51   26   5.8   3.2   28.6  83.4    10.3      M    M
 16500   -6.4  20.5   315   49   25   5.0   2.7   27.8  82.1     9.7      M    M
 16000   -5.6  21.9   315   46   24   5.1   2.8   27.0  80.6     9.0      M    M
 15500   -4.9  23.2   315   43   22   4.6   2.5   26.2  79.2     8.3      M    M
 15000   -4.3  24.3   315   39   20   4.4   2.4   25.3  77.6     7.5      M    M
 14500   -3.6  25.5   320   35   18   4.3   2.4   24.4  76.0     6.7      M    M
 14000   -3.0  26.6   320   31   16   4.2   2.3   23.5  74.3     5.9      M    M
 13500   -2.4  27.7   320   27   14   4.2   2.3   22.6  72.7     5.1      M    M
 13000   -1.8  28.8   320   23   12   4.4   2.4   21.7  71.1     4.3      M    M
 12500   -1.2  29.8   320   19   10   4.8   2.6   20.8  69.5     3.4      M    M
 12000   -0.2  31.6   325   20   10   7.3   4.0   20.3  68.5     2.9      M    M
 11500    0.9  33.6   330   22   11   6.9   3.8   19.9  67.8     2.6      M    M
 11000    1.7  35.1   325   22   12   4.8   2.6   19.2  66.6     1.9      M    M
 10500    2.4  36.3   320   22   11   5.0   2.7   18.5  65.2     1.2      M    M
 10250    2.8  37.0   320   24   12   5.4   2.9   18.1  64.6     0.8      M    M
 10000    3.2  37.8   320   28   14   4.6   2.5   17.7  63.9     0.5      M    M
  9750    3.4  38.1   315   31   16   3.8   2.1   17.3  63.1     0.0      M    M
  9500    3.7  38.7   310   35   18   3.8   2.1   16.8  62.3    -0.4    291  1.5
  9250    3.9  39.0   310   36   19   3.5   1.9   16.3  61.4    -0.9    276  1.4
  9000    4.2  39.6   310   37   19   3.0   1.6   15.8  60.5    -1.4    261  1.3
  8750    4.3  39.7   305   37   19   0.7   0.4   15.2  59.4    -2.0    250  1.3
  8500    4.4  39.9   305   36   19   3.4   1.9   14.6  58.2    -2.7    241  1.2
  8250    4.8  40.6   305   34   18   6.5   3.6   14.3  57.7    -3.0    220  1.1
  8000    5.2  41.4   305   32   16   5.6   3.1   14.0  57.1    -3.3    200  1.0
  7750    5.7  42.3   305   30   15   6.5   3.5   13.7  56.6    -3.6    180  0.9
  7500    6.2  43.2   305   27   14   7.4   4.0   13.5  56.2    -3.8    157  0.8
  7250    6.7  44.1   305   25   13   7.6   4.2   13.3  55.9    -4.0    133  0.7
  7000    7.3  45.1   300   23   12   7.5   4.1   13.1  55.6    -4.2    108  0.6
  6750    7.9  46.2   300   20   10   8.3   4.5   13.0  55.4    -4.3     83  0.4
  6500    8.5  47.3   300   18    9   8.6   4.7   12.9  55.2    -4.4     57  0.3
  6250    9.2  48.6   300   16    8   9.2   5.0   12.8  55.0    -4.5     30  0.2
  6000    9.8  49.6   295   14    7   6.4   3.5   12.7  54.9    -4.6      3  0.0
  5750    9.8  49.6   290   11    6 -10.2  -5.6   12.0  53.5    -5.4      M    M
  5500    8.2  46.8   270    7    4 -28.8 -15.8    9.7  49.4    -7.7     37  0.2

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

           10/23/2017 at 0900 MDT          |       10/23/2017 at 1200 MDT
                                           |
K index... +0.4  LI... +8.7                | K index... -10.5  LI... +9.5
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -62.8 -81.0  300  55 28   0.8   0.4 | -62.4 -80.3  315  53 27   0.4   0.2
 45000 -61.9 -79.4  305  72 37  -0.9  -0.5 | -61.8 -79.2  315  65 33   0.6   0.3
 40000 -63.2 -81.8  320  94 48  -1.9  -1.0 | -60.9 -77.6  310  80 41   0.8   0.4
 38000 -58.7 -73.7  320  97 50   8.7   4.8 | -56.9 -70.4  325  88 45   7.2   3.9
 36000 -53.5 -64.3  325  98 50   8.7   4.8 | -52.6 -62.7  335 100 51   7.2   3.9
 34000 -47.2 -53.0  320  93 48   9.6   5.3 | -47.1 -52.8  335 101 52   8.7   4.8
 32000 -41.4 -42.5  310  85 44   9.6   5.3 | -41.9 -43.4  325  95 49   8.7   4.8
 30000 -36.0 -32.8  305  81 42   8.7   4.8 | -36.2 -33.2  320  94 48   9.8   5.4
 29000 -33.4 -28.1  305  79 41   8.7   4.8 | -33.3 -27.9  320  94 48   9.8   5.4
 28000 -30.8 -23.4  310  78 40   9.0   4.9 | -30.3 -22.5  320  94 48  10.0   5.5
 27000 -28.7 -19.7  310  77 40   6.3   3.4 | -27.8 -18.0  320  93 48   8.1   4.4
 26000 -26.8 -16.2  310  76 39   6.3   3.4 | -25.4 -13.7  320  91 47   8.1   4.4
 25000 -25.0 -13.0  315  76 39   6.3   3.5 | -22.9  -9.2  320  89 46   8.0   4.4
 24000 -22.9  -9.2  315  75 38   7.4   4.1 | -20.9  -5.6  320  85 44   5.6   3.1
 23000 -20.6  -5.1  315  72 37   7.5   4.1 | -19.3  -2.7  320  79 41   5.6   3.1
 22000 -18.4  -1.1  315  69 36   7.5   4.1 | -17.6   0.3  315  73 38   5.6   3.0
 21000 -16.2   2.8  315  67 35   7.1   3.9 | -15.7   3.7  315  71 36   7.0   3.8
 20000 -14.1   6.6  315  65 34   7.1   3.9 | -13.6   7.5  315  69 36   7.0   3.8
 19500 -13.0   8.6  315  64 33   7.1   3.9 | -12.6   9.3  315  69 35   7.0   3.8
 19000 -12.0  10.4  315  63 32   6.6   3.6 | -11.6  11.1  315  68 35   6.9   3.8
 18500 -11.1  12.0  315  62 32   5.7   3.1 | -10.6  12.9  315  67 35   6.6   3.6
 18000 -10.3  13.5  315  60 31   5.8   3.2 |  -9.6  14.7  320  66 34   6.7   3.7
 17500  -9.0  15.8  315  57 29   5.5   3.0 |  -8.2  17.2  320  64 33   5.5   3.0
 17000  -8.2  17.2  315  55 28   5.6   3.1 |  -7.4  18.7  320  62 32   5.6   3.1
 16500  -7.5  18.5  315  52 27   4.4   2.4 |  -6.6  20.1  320  60 31   5.2   2.9
 16000  -6.8  19.8  315  50 26   4.5   2.5 |  -5.7  21.7  320  57 30   5.4   2.9
 15500  -6.2  20.8  315  47 24   4.1   2.2 |  -5.0  23.0  315  55 28   3.6   2.0
 15000  -5.6  21.9  315  43 22   3.9   2.2 |  -4.5  23.9  315  51 27   3.0   1.6
 14500  -5.0  23.0  315  40 20   3.8   2.1 |  -4.1  24.6  315  48 25   2.7   1.5
 14000  -4.5  23.9  315  36 19   3.7   2.0 |  -3.7  25.3  315  45 23   2.4   1.3
 13500  -4.0  24.8  315  33 17   3.7   2.0 |  -3.4  25.9  310  41 21   2.1   1.2
 13000  -3.4  25.9  315  30 15   3.7   2.1 |  -3.2  26.2  310  38 19   1.2   0.6
 12500  -2.9  26.8  320  27 14   3.9   2.1 |  -3.1  26.4  310  34 18   1.5   0.8
 12000  -2.3  27.9  320  26 13   4.4   2.4 |  -2.7  27.1  310  32 16   3.0   1.6
 11500  -1.7  28.9  325  26 13   4.7   2.6 |  -2.4  27.7  305  30 15   3.2   1.7
 11000  -0.9  30.4  325  27 14   6.1   3.3 |  -1.9  28.6  305  29 15   4.0   2.2
 10500   0.0  32.0  320  29 15   5.4   3.0 |  -1.3  29.7  305  28 14   4.0   2.2
 10250   0.3  32.5  320  30 15   4.1   2.2 |  -1.0  30.2  305  28 14   4.2   2.3
 10000   0.6  33.1  320  31 16   4.3   2.3 |  -0.8  30.6  305  29 15   3.6   2.0
  9750   0.9  33.6  315  30 16   4.7   2.6 |  -0.6  30.9  300  26 14   2.2   1.2
  9500   1.3  34.3  315  30 15   4.5   2.5 |  -0.5  31.1  300  24 12   4.3   2.4
  9250   1.6  34.9  315  29 15   4.6   2.5 |  -0.1  31.8  295  22 11   6.1   3.3
  9000   1.9  35.4  315  28 15   3.9   2.1 |   0.4  32.7  295  19 10   6.6   3.6
  8750   2.1  35.8  315  27 14   2.0   1.1 |   1.0  33.8  295  16  8   9.4   5.1
  8500   2.2  36.0  315  24 13   4.5   2.5 |   1.7  35.1  295  13  7   9.7   5.3
  8250   2.7  36.9  315  23 12   7.0   3.8 |   2.4  36.3  300  11  6   8.7   4.8
  8000   3.2  37.8  320  21 11   6.5   3.6 |   3.0  37.4  300   9  5   9.3   5.1
  7750   3.7  38.7  320  19 10   8.5   4.7 |   3.8  38.8  305   7  4  10.7   5.9
  7500   4.4  39.9  325  17  9   8.8   4.8 |   4.6  40.3  310   6  3  10.5   5.8
  7250   5.0  41.0  330  15  8   8.4   4.6 |   5.3  41.5  310   6  3  10.2   5.6
  7000   5.6  42.1  335  13  7   7.3   4.0 |   6.1  43.0  315   5  3   9.1   5.0
  6750   6.1  43.0  340  12  6   7.7   4.2 |   6.7  44.1  320   5  3   9.1   5.0
  6500   6.8  44.2  345  11  5   9.1   5.0 |   7.5  45.5  320   5  2  10.6   5.8
  6250   7.5  45.5  350   9  5   9.4   5.2 |   8.3  46.9  325   4  2  10.1   5.6
  6000   8.1  46.6  355   8  4   6.7   3.7 |   9.0  48.2  325   4  2  10.6   5.8
  5750   8.4  47.1  350   7  3   2.6   1.4 |   9.9  49.8  330   4  2  15.6   8.6
  5500   8.6  47.5  340   3  2   4.3   2.3 |  11.4  52.5  335   4  2  22.8  12.5

           10/23/2017 at 1500 MDT          |       10/23/2017 at 1800 MDT
                                           |
K index... -6.2  LI... +9.3                | K index... -0.7  LI... +8.8
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -62.3 -80.1  320  56 29   0.8   0.4 | -61.4 -78.5  325  58 30   1.0   0.6
 45000 -61.4 -78.5  320  70 36  -1.0  -0.5 | -60.3 -76.5  325  72 37  -1.2  -0.6
 40000 -62.9 -81.2  325  93 48   0.7   0.4 | -62.1 -79.8  320  98 51   0.1   0.0
 38000 -57.8 -72.0  325  93 48   9.3   5.1 | -57.3 -71.1  325  96 49   8.7   4.8
 36000 -52.2 -62.0  320  92 47   9.3   5.1 | -52.0 -61.6  325  93 48   8.7   4.8
 34000 -46.2 -51.2  320  90 46   8.8   4.8 | -46.3 -51.3  325  89 46   8.3   4.5
 32000 -40.9 -41.6  325  88 45   8.8   4.8 | -41.4 -42.5  330  86 44   8.3   4.5
 30000 -35.6 -32.1  325  87 45   8.7   4.8 | -36.0 -32.8  330  84 43   9.3   5.1
 29000 -33.0 -27.4  325  88 45   8.7   4.8 | -33.2 -27.8  330  84 43   9.3   5.1
 28000 -30.4 -22.7  325  88 45   8.7   4.8 | -30.4 -22.7  330  83 43   9.4   5.2
 27000 -27.8 -18.0  325  88 45   8.5   4.7 | -27.8 -18.0  330  78 40   8.6   4.7
 26000 -25.3 -13.5  330  87 45   8.5   4.7 | -25.2 -13.4  325  71 37   8.6   4.7
 25000 -22.8  -9.0  330  86 44   8.5   4.6 | -22.6  -8.7  325  64 33   8.6   4.7
 24000 -20.6  -5.1  330  85 44   6.5   3.6 | -20.4  -4.7  325  64 33   6.5   3.6
 23000 -18.6  -1.5  330  84 43   6.5   3.5 | -18.5  -1.3  330  70 36   6.4   3.5
 22000 -16.7   1.9  325  83 43   6.5   3.6 | -16.5   2.3  335  77 39   6.5   3.5
 21000 -14.9   5.2  325  81 42   6.2   3.4 | -14.9   5.2  335  77 40   5.1   2.8
 20000 -13.0   8.6  320  79 41   6.2   3.4 | -13.4   7.9  330  74 38   5.1   2.8
 19500 -12.1  10.2  320  78 40   6.2   3.4 | -12.6   9.3  325  72 37   5.1   2.8
 19000 -11.2  11.8  320  77 40   6.1   3.4 | -11.9  10.6  325  71 37   4.9   2.7
 18500 -10.3  13.5  320  75 39   6.1   3.3 | -11.2  11.8  325  70 36   4.6   2.5
 18000  -9.4  15.1  320  74 38   6.3   3.4 | -10.5  13.1  325  69 35   4.9   2.7
 17500  -8.3  17.1  320  71 37   4.1   2.2 |  -9.9  14.2  325  66 34   1.3   0.7
 17000  -7.7  18.1  320  69 35   4.1   2.3 |  -9.7  14.5  325  63 33   1.3   0.7
 16500  -7.1  19.2  320  65 34   3.8   2.1 |  -9.5  14.9  325  60 31   1.9   1.1
 16000  -6.5  20.3  320  61 31   3.8   2.1 |  -9.2  15.4  325  57 29   1.8   1.0
 15500  -5.9  21.4  320  56 29   3.7   2.0 |  -8.8  16.2  325  53 28   3.5   1.9
 15000  -5.4  22.3  320  52 27   3.6   2.0 |  -8.2  17.2  320  50 26   4.0   2.2
 14500  -4.8  23.4  315  48 25   3.6   2.0 |  -7.6  18.3  320  46 24   4.2   2.3
 14000  -4.3  24.3  315  46 23   3.6   2.0 |  -7.0  19.4  320  42 22   4.4   2.4
 13500  -3.8  25.2  315  43 22   3.5   1.9 |  -6.4  20.5  315  38 20   4.7   2.6
 13000  -3.3  26.1  315  39 20   3.2   1.8 |  -5.7  21.7  315  34 18   5.2   2.9
 12500  -2.8  27.0  310  35 18   3.5   1.9 |  -5.0  23.0  315  30 16   5.6   3.0
 12000  -2.2  28.0  310  32 17   4.8   2.6 |  -4.1  24.6  320  28 14   6.4   3.5
 11500  -1.5  29.3  310  30 16   4.8   2.6 |  -3.2  26.2  320  26 13   6.6   3.6
 11000  -0.8  30.6  305  28 14   5.0   2.7 |  -2.2  28.0  320  24 12   7.2   3.9
 10500  -0.1  31.8  300  26 13   4.5   2.4 |  -1.1  30.0  325  22 11   6.7   3.7
 10250   0.1  32.2  300  25 13   2.8   1.5 |  -0.7  30.7  325  21 11   5.5   3.0
 10000   0.3  32.5  300  24 12   3.7   2.1 |  -0.3  31.5  330  21 11   6.6   3.6
  9750   0.5  32.9  300  20 10   4.5   2.5 |   0.3  32.5  335  20 10   8.0   4.4
  9500   0.8  33.4  305  15  8   5.7   3.2 |   0.8  33.4  340  19 10   6.8   3.7
  9250   1.3  34.3  310  13  7   7.1   3.9 |   1.3  34.3  340  18  9   5.8   3.2
  9000   1.9  35.4  315  11  6   7.7   4.2 |   1.7  35.1  345  17  9   6.3   3.4
  8750   2.5  36.5  320   9  5   9.7   5.3 |   2.2  36.0  350  16  8   7.1   3.9
  8500   3.2  37.8  330   8  4   9.7   5.3 |   2.7  36.9  355  15  8   7.7   4.2
  8250   3.9  39.0  335   8  4   9.1   5.0 |   3.3  37.9  355  13  7   7.8   4.3
  8000   4.6  40.3  335   8  4   9.7   5.3 |   3.9  39.0  360  12  6   7.4   4.1
  7750   5.4  41.7  340   8  4  10.8   5.9 |   4.4  39.9  010  11  6   8.6   4.7
  7500   6.2  43.2  345   7  4  10.3   5.7 |   5.1  41.2  015  10  5   9.8   5.4
  7250   6.9  44.4  345   7  4  10.1   5.6 |   5.8  42.4  020  10  5   9.9   5.4
  7000   7.7  45.9  345   7  4   8.8   4.8 |   6.5  43.7  030  10  5   8.7   4.8
  6750   8.3  46.9  350   7  4   9.1   5.0 |   7.2  45.0  035   9  5   8.6   4.7
  6500   9.1  48.4  350   7  4  10.9   6.0 |   7.9  46.2  035   9  5  10.0   5.5
  6250   9.9  49.8  350   7  4  10.4   5.7 |   8.6  47.5  040   9  5   9.4   5.2
  6000  10.6  51.1  355   7  4  10.6   5.8 |   9.3  48.7  040   9  5  10.4   5.7
  5750  11.5  52.7  355   7  4  14.8   8.1 |  10.1  50.2  045   8  4   9.2   5.0
  5500  12.9  55.2  360   7  4  21.6  11.8 |  10.6  51.1  045   7  3   4.6   2.5
________________________________________________________________________________

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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