Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 201313
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0713 MDT Wednesday, September 20, 2017

This forecast is for Wednesday, September 20, 2017:

If the trigger temperature of 67.5 F/19.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 903 ft/min (4.6 m/s)
   Maximum height of thermals.................. 16431 ft MSL (11146 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 1115 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................. 13175 ft MSL (7889 ft AGL)
Thermal soaring outlook for Thursday 09/21..... Excellent

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 16588 ft MSL (11303 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 19045 ft MSL (13760 ft AGL)
Wave soaring outlook for Thursday 09/21........ Poor

Remarks...

Sunrise/Sunset.................... 06:45:29 / 19:00:53 MDT
Total possible sunshine........... 12 hr 15 min 24 sec (735 min 24 sec)
Altitude of sun at 12:52:42 MDT... 51.03 degrees

Upper air data from rawinsonde observation taken on 09/20/2017 at 0600 MDT

Freezing level.................. 13412 ft MSL (8127 ft AGL)
Convective condensation level... 20153 ft MSL (14868 ft AGL)
Lifted condensation level....... 17316 ft MSL (12031 ft AGL)
Lifted index.................... +4.3
K index......................... +13.6

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  -67.7 -89.9   265   56   29   2.8   1.6   82.9 181.2    31.8      M    M
 45000  -66.5 -87.7   255   74   38   8.3   4.5   60.0 140.0    20.0      M    M
 40000  -54.7 -66.5   260   75   39   5.6   3.1   54.7 130.5    18.0      M    M
 38000  -51.2 -60.2   260   74   38   5.7   3.1   50.8 123.4    15.7      M    M
 36000  -47.8 -54.0   265   74   38   5.8   3.2   47.5 117.6    13.9      M    M
 34000  -42.9 -45.2   265   74   38   9.3   5.1   46.4 115.5    13.4      M    M
 32000  -38.5 -37.3   255   67   35   6.9   3.8   44.4 111.9    12.3      M    M
 30000  -33.7 -28.7   255   59   31   8.6   4.7   43.1 109.7    11.6      M    M
 29000  -31.2 -24.2   255   57   30   8.6   4.7   42.6 108.6    11.3      M    M
 28000  -27.9 -18.2   255   55   28   8.6   4.7   42.0 107.5    11.0      M    M
 27000  -25.4 -13.7   250   54   28   8.6   4.7   41.6 106.9    10.9      M    M
 26000  -22.8  -9.0   250   52   27   8.6   4.7   41.3 106.4    10.8      M    M
 25000  -20.2  -4.4   255   52   27   8.6   4.7   40.8 105.5    10.5      M    M
 24000  -17.8  -0.0   255   53   27   7.1   3.9   40.1 104.1    10.0      M    M
 23000  -15.6   3.9   260   54   28   7.2   3.9   39.0 102.2     9.2      M    M
 22000  -13.5   7.7   260   56   29   7.2   3.9   38.1 100.5     8.5      M    M
 21000  -11.4  11.5   265   58   30   7.2   4.0   37.3  99.1     7.9      M    M
 20000   -9.2  15.4   265   60   31   7.2   4.0   36.6  97.8     7.4      M    M
 19500   -8.2  17.2   265   61   32   7.2   4.0   36.1  96.9     7.0      M    M
 19000   -7.1  19.2   265   63   32   7.2   4.0   35.6  96.1     6.6      M    M
 18500   -6.1  21.0   265   63   32   6.8   3.7   35.1  95.2     6.2      M    M
 18000   -5.0  23.0   265   62   32   6.2   3.4   34.6  94.4     5.8      M    M
 17500   -4.8  23.4   265   57   29  -1.4  -0.8   33.2  91.8     4.6      M    M
 17000   -5.0  23.0   265   51   26  -0.0  -0.0   31.4  88.6     3.0      M    M
 16500   -5.7  21.7   260   46   24  -9.7  -5.3   29.1  84.3     0.8      M    M
 16000   -5.9  21.4   260   40   21   6.6   3.6   27.3  81.1    -0.8    888  4.5
 15500   -5.2  22.6   260   36   18   5.4   3.0   26.5  79.7    -1.6    852  4.3
 15000   -4.5  23.9   255   31   16   7.1   3.9   25.8  78.4    -2.3    815  4.1
 14500   -3.2  26.2   255   27   14   8.5   4.7   25.6  78.1    -2.5    762  3.9
 14000   -1.2  29.8   250   22   11   8.6   4.7   25.4  77.7    -2.7    682  3.5
 13500    0.0  32.0   245   22   12   8.6   4.7   25.2  77.3    -2.9    628  3.2
 13000    1.3  34.3   240   23   12   8.6   4.7   25.0  77.0    -3.1    575  2.9
 12500    2.6  36.7   240   23   12   8.6   4.7   24.8  76.7    -3.3    522  2.6
 12000    3.9  39.0   235   24   12   8.6   4.7   24.7  76.4    -3.4    468  2.4
 11500    5.2  41.4   230   23   12   8.6   4.7   24.5  76.1    -3.6    415  2.1
 11000    6.5  43.7   225   22   11   8.6   4.7   24.3  75.7    -3.8    362  1.8
 10500    7.8  46.0   215   22   11   8.7   4.8   24.1  75.3    -4.1    308  1.6
 10250    8.4  47.1   210   23   12   8.1   4.5   24.0  75.1    -4.2    281  1.4
 10000    9.0  48.2   200   24   13   7.1   3.9   23.8  74.8    -4.3    257  1.3
  9750    9.4  48.9   190   27   14   3.7   2.0   23.5  74.3    -4.7    237  1.2
  9500    9.0  48.2   180   30   15 -17.7  -9.7   22.4  72.3    -5.8    241  1.2
  9250    7.0  44.6   175   34   17 -24.3 -13.3   19.6  67.2    -8.5    293  1.5
  9000    5.9  42.6   170   37   19  -5.7  -3.1   17.7  63.9   -10.4    319  1.6
  8750    5.8  42.4   170   36   18  -0.1  -0.0   16.8  62.3   -11.2    315  1.6
  8500    5.7  42.3   165   34   18  -2.8  -1.6   16.0  60.7   -12.1    311  1.6
  8250    5.6  42.1   165   33   17   2.6   1.4   15.1  59.2   -13.0    307  1.6
  8000    6.1  43.0   160   32   16   7.7   4.2   14.9  58.7   -13.2    285  1.4
  7750    6.6  43.9   155   31   16   6.8   3.7   14.6  58.3   -13.5    263  1.3
  7500    7.1  44.8   155   29   15   6.3   3.4   14.4  57.9   -13.8    240  1.2
  7250    7.6  45.7   150   28   14   9.4   5.1   14.2  57.5   -14.0    218  1.1
  7000    8.1  46.6   145   27   14  -2.5  -1.4   14.0  57.2   -14.3    195  1.0
  6750    7.2  45.0   145   26   13 -16.9  -9.2   12.3  54.1   -16.0    216  1.1
  6500    6.3  43.3   140   25   13  -1.1  -0.6   10.7  51.3   -17.6    233  1.2
  6250    6.8  44.2   140   25   13   9.0   5.0   10.5  50.9   -17.9    211  1.1
  6000    7.3  45.1   135   24   12   6.3   3.4   10.3  50.5   -18.1    189  1.0
  5750    7.8  46.0   135   19   10   7.2   3.9   10.1  50.1   -18.4    167  0.8
  5500    8.3  46.9   135   14    7   6.3   3.4    9.8  49.7   -18.7    145  0.7

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

           09/20/2017 at 0900 MDT          |       09/20/2017 at 1200 MDT
                                           |
K index... +8.8  LI... +5.2                | K index... +1.1  LI... +5.4
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 -63.3 -81.9  260  40 21  -1.8  -1.0 | -64.5 -84.1  250  44 22  -0.6  -0.3
 45000 -63.9 -83.0  260  71 37   5.5   3.0 | -63.8 -82.8  255  69 36   4.7   2.6
 40000 -55.6 -68.1  265  77 40   6.1   3.3 | -56.7 -70.1  260  76 39   6.5   3.6
 38000 -51.8 -61.2  265  74 38   6.4   3.5 | -52.3 -62.1  260  71 37   7.2   3.9
 36000 -48.0 -54.4  265  71 36   6.3   3.5 | -48.0 -54.4  260  67 34   7.2   3.9
 34000 -43.5 -46.3  265  68 35   8.2   4.5 | -43.3 -45.9  260  63 33   8.4   4.6
 32000 -38.6 -37.5  265  65 34   8.2   4.5 | -37.6 -35.7  260  61 31   8.4   4.6
 30000 -33.1 -27.6  255  61 31   8.0   4.4 | -32.5 -26.5  260  59 30   8.6   4.7
 29000 -30.7 -23.3  255  58 30   8.0   4.4 | -30.0 -22.0  260  58 30   8.6   4.7
 28000 -28.3 -18.9  250  56 29   8.0   4.4 | -27.4 -17.3  260  57 29   8.7   4.8
 27000 -25.9 -14.6  250  54 28   8.0   4.4 | -25.1 -13.2  260  54 28   7.2   4.0
 26000 -23.6 -10.5  250  53 27   8.0   4.4 | -23.0  -9.4  260  52 27   7.2   4.0
 25000 -21.2  -6.2  255  51 26   8.0   4.4 | -20.8  -5.4  265  50 26   7.3   4.0
 24000 -18.9  -2.0  255  51 26   7.5   4.1 | -18.5  -1.3  265  48 25   8.0   4.4
 23000 -16.7   1.9  260  51 26   7.5   4.1 | -16.1   3.0  265  48 25   8.0   4.4
 22000 -14.4   6.1  265  51 26   7.5   4.1 | -13.7   7.3  265  48 25   8.1   4.4
 21000 -12.3   9.9  265  50 26   6.7   3.7 | -11.6  11.1  270  48 25   6.5   3.6
 20000 -10.4  13.3  265  47 24   6.7   3.7 |  -9.7  14.5  265  49 25   6.5   3.6
 19500  -9.4  15.1  265  46 24   6.7   3.7 |  -8.7  16.3  265  50 26   6.5   3.6
 19000  -8.4  16.9  265  45 23   6.7   3.7 |  -7.8  18.0  265  50 26   6.5   3.6
 18500  -7.4  18.7  260  43 22   6.4   3.5 |  -6.8  19.8  265  49 25   6.4   3.5
 18000  -6.5  20.3  260  40 21   6.4   3.5 |  -5.9  21.4  270  47 24   6.4   3.5
 17500  -5.5  22.1  260  38 20   5.8   3.2 |  -4.9  23.2  270  46 24   7.7   4.2
 17000  -4.7  23.5  255  37 19   5.5   3.0 |  -3.6  25.5  270  45 23   8.1   4.5
 16500  -3.9  25.0  255  36 19   5.5   3.0 |  -1.8  28.8  270  43 22   6.4   3.5
 16000  -2.7  27.1  255  37 19   5.3   2.9 |  -0.9  30.4  265  44 22   5.9   3.2
 15500  -2.0  28.4  260  37 19   4.6   2.5 |  -0.0  32.0  265  44 23   4.7   2.6
 15000  -1.6  29.1  260  37 19   2.7   1.5 |   0.3  32.5  265  43 22   2.2   1.2
 14500  -1.2  29.8  260  36 19   2.8   1.6 |   0.6  33.1  265  42 22   2.4   1.3
 14000  -0.8  30.6  260  34 17   3.1   1.7 |   0.6  33.1  265  39 20  -0.6  -0.4
 13500  -0.4  31.3  260  30 16   2.7   1.5 |   0.4  32.7  260  33 17  -0.7  -0.4
 13000   0.2  32.4  260  27 14   7.7   4.2 |   0.6  33.1  260  28 14   5.0   2.8
 12500   1.3  34.3  260  23 12   7.6   4.2 |   1.3  34.3  255  23 12   4.8   2.6
 12000   2.4  36.3  260  20 10   7.5   4.1 |   2.1  35.8  250  18  9   8.3   4.5
 11500   3.6  38.5  260  18  9   7.5   4.1 |   3.4  38.1  245  14  7   8.8   4.8
 11000   4.7  40.5  260  15  8   7.3   4.0 |   4.7  40.5  235  11  6   7.0   3.8
 10500   5.7  42.3  260  13  7   7.9   4.3 |   5.7  42.3  230  10  5   6.0   3.3
 10250   6.3  43.3  265  12  6   4.5   2.5 |   6.2  43.2  230   9  5   9.5   5.2
 10000   6.5  43.7  265  11  6   4.1   2.2 |   7.0  44.6  225   8  4  10.0   5.5
  9750   7.0  44.6  270  10  5   6.9   3.8 |   7.6  45.7  220   8  4   6.7   3.7
  9500   7.4  45.3  270  10  5   6.9   3.8 |   8.2  46.8  215   7  4   8.0   4.4
  9250   7.9  46.2  275   9  5   4.1   2.2 |   8.7  47.7  210   6  3   6.1   3.3
  9000   8.1  46.6  270   8  4   2.8   1.6 |   9.1  48.4  200   6  3   4.8   2.6
  8750   8.5  47.3  260   8  4   5.2   2.9 |   9.5  49.1  190   6  3   5.6   3.1
  8500   8.8  47.8  250   7  4   5.1   2.8 |   9.9  49.8  180   6  3   4.9   2.7
  8250   9.2  48.6  235   7  4   4.4   2.4 |  10.3  50.5  175   7  3   6.8   3.8
  8000   9.5  49.1  215   9  5   3.5   1.9 |  10.9  51.6  170   7  3   8.5   4.7
  7750   9.8  49.6  200  11  6   3.7   2.0 |  11.5  52.7  170   6  3   7.7   4.2
  7500  10.1  50.2  195  13  7   3.1   1.7 |  12.1  53.8  170   6  3   7.8   4.3
  7250  10.2  50.4  190  15  8  -0.2  -0.1 |  12.7  54.9  170   6  3   8.7   4.8
  7000  10.1  50.2  185  16  8  -1.5  -0.8 |  13.4  56.1  170   6  3   9.4   5.2
  6750   9.9  49.8  180  17  9  -4.3  -2.4 |  14.1  57.4  170   6  3   9.9   5.4
  6500   9.6  49.3  175  18  9  -0.7  -0.4 |  14.9  58.8  170   6  3  10.7   5.8
  6250   9.9  49.8  170  16  8   6.6   3.6 |  15.7  60.3  170   6  3  11.1   6.1
  6000  10.3  50.5  165  13  7   5.3   2.9 |  16.5  61.7  170   5  3  10.8   5.9
  5750  10.8  51.4  160  11  6   9.3   5.1 |  17.3  63.1  170   5  3  11.9   6.5
  5500  11.8  53.2  160  10  5  19.7  10.8 |  18.5  65.3  170   5  3  20.0  11.0

           09/20/2017 at 1500 MDT          |       09/20/2017 at 1800 MDT
                                           |
K index... +12.2  LI... +4.1               | K index... +16.3  LI... +2.9
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 -66.2 -87.2  245  42 21   0.2   0.1 | -65.8 -86.4  245  42 22   0.4   0.2
 45000 -64.2 -83.6  255  57 29   5.1   2.8 | -63.8 -82.8  250  49 25   4.7   2.6
 40000 -56.5 -69.7  250  64 33   7.6   4.2 | -56.5 -69.7  245  59 30   7.7   4.2
 38000 -51.8 -61.2  255  64 33   7.8   4.3 | -51.8 -61.2  245  60 31   7.9   4.4
 36000 -47.1 -52.8  255  64 33   7.8   4.3 | -47.0 -52.6  245  62 32   7.9   4.4
 34000 -42.6 -44.7  255  62 32   7.5   4.1 | -42.5 -44.5  250  61 32   7.4   4.1
 32000 -38.1 -36.6  255  59 30   7.5   4.1 | -38.0 -36.4  250  59 30   7.4   4.1
 30000 -32.5 -26.5  260  57 30   8.6   4.7 | -32.5 -26.5  255  57 29   8.7   4.8
 29000 -29.9 -21.8  260  57 29   8.6   4.7 | -29.8 -21.6  255  56 29   8.7   4.8
 28000 -27.3 -17.1  260  57 29   8.6   4.7 | -27.2 -17.0  260  55 28   8.7   4.8
 27000 -24.9 -12.8  260  56 29   7.8   4.3 | -24.7 -12.5  260  54 28   8.6   4.7
 26000 -22.6  -8.7  260  55 28   7.8   4.3 | -22.1  -7.8  260  53 27   8.6   4.7
 25000 -20.2  -4.4  260  54 28   7.8   4.3 | -19.5  -3.1  260  52 27   8.6   4.7
 24000 -18.1  -0.6  265  52 27   6.8   3.7 | -17.4   0.7  260  50 26   6.1   3.4
 23000 -16.1   3.0  265  49 25   6.8   3.7 | -15.6   3.9  255  47 24   6.1   3.3
 22000 -14.1   6.6  265  47 24   6.8   3.7 | -13.7   7.3  255  45 23   6.1   3.3
 21000 -11.9  10.6  265  45 23   7.6   4.2 | -11.9  10.6  255  44 22   6.1   3.3
 20000  -9.6  14.7  265  45 23   7.6   4.2 | -10.1  13.8  255  43 22   6.1   3.4
 19500  -8.5  16.7  265  45 23   7.6   4.2 |  -9.2  15.4  255  43 22   6.2   3.4
 19000  -7.4  18.7  265  45 23   7.2   3.9 |  -8.3  17.1  255  43 22   6.5   3.6
 18500  -6.5  20.3  265  46 23   5.8   3.2 |  -7.3  18.9  255  43 22   7.5   4.1
 18000  -5.6  21.9  265  46 24   5.9   3.2 |  -6.2  20.8  255  42 22   7.6   4.2
 17500  -4.7  23.5  260  46 24   6.5   3.6 |  -5.1  22.8  255  41 21   6.5   3.6
 17000  -3.7  25.3  260  46 23   6.6   3.6 |  -4.2  24.4  255  39 20   6.4   3.5
 16500  -2.8  27.0  260  45 23   6.2   3.4 |  -3.3  26.1  255  37 19   6.3   3.5
 16000  -1.6  29.1  260  43 22   5.1   2.8 |  -2.0  28.4  250  33 17   6.2   3.4
 15500  -0.9  30.4  255  42 21   4.7   2.6 |  -1.2  29.8  250  31 16   6.8   3.8
 15000  -0.4  31.3  255  39 20   4.3   2.3 |  -0.1  31.8  250  29 15   7.7   4.2
 14500   0.2  32.4  255  36 19   4.7   2.6 |   1.0  33.8  245  27 14   7.9   4.3
 14000   1.1  34.0  255  33 17   7.7   4.2 |   2.3  36.1  245  26 13   9.1   5.0
 13500   2.1  35.8  250  29 15   7.4   4.1 |   3.6  38.5  240  24 12   9.1   5.0
 13000   3.3  37.9  250  26 13   8.8   4.8 |   4.9  40.8  240  22 11   8.0   4.4
 12500   4.6  40.3  245  23 12   8.9   4.9 |   6.1  43.0  240  20 10   8.2   4.5
 12000   5.8  42.4  245  21 11   6.2   3.4 |   7.2  45.0  235  18  9   6.6   3.6
 11500   6.6  43.9  240  18  9   6.2   3.4 |   8.1  46.6  230  14  7   6.6   3.6
 11000   7.5  45.5  230  14  7   5.1   2.8 |   9.1  48.4  225  11  6   5.6   3.1
 10500   8.2  46.8  220  11  6   4.3   2.4 |   9.9  49.8  220   8  4   5.5   3.0
 10250   8.6  47.5  210   9  5   8.5   4.7 |  10.3  50.5  215   6  3   8.7   4.8
 10000   9.4  48.9  195   8  4  10.1   5.6 |  11.1  52.0  210   5  3   9.7   5.3
  9750  10.0  50.0  190   7  4   7.4   4.0 |  11.7  53.1  205   4  2   8.0   4.4
  9500  10.6  51.1  185   7  3   7.9   4.4 |  12.3  54.1  195   3  2   8.3   4.5
  9250  11.2  52.2  175   6  3   8.4   4.6 |  12.9  55.2  180   3  1   9.0   4.9
  9000  11.9  53.4  170   6  3   9.0   4.9 |  13.6  56.5  165   3  1   8.9   4.9
  8750  12.5  54.5  170   6  3   8.8   4.8 |  14.2  57.6  155   3  1   8.2   4.5
  8500  13.2  55.8  170   5  3   8.3   4.6 |  14.8  58.6  145   3  2   7.7   4.2
  8250  13.8  56.8  165   5  3  10.4   5.7 |  15.5  59.9  140   3  2  10.5   5.8
  8000  14.7  58.5  165   5  3  11.3   6.2 |  16.3  61.3  135   4  2  11.1   6.1
  7750  15.4  59.7  165   5  3   9.7   5.3 |  17.0  62.6  130   4  2   8.4   4.6
  7500  16.2  61.2  160   5  3   9.8   5.4 |  17.7  63.9  130   4  2   8.5   4.7
  7250  16.9  62.4  160   5  2   9.7   5.3 |  18.3  64.9  130   4  2   9.8   5.4
  7000  17.6  63.7  160   5  2   9.6   5.3 |  19.1  66.4  125   4  2  10.7   5.9
  6750  18.4  65.1  160   5  2   9.5   5.2 |  19.9  67.8  125   4  2   9.6   5.3
  6500  19.1  66.4  160   4  2  10.0   5.5 |  20.6  69.1  120   4  2   9.5   5.2
  6250  19.9  67.8  160   4  2  11.0   6.0 |  21.3  70.3  115   3  2  10.2   5.6
  6000  20.7  69.3  160   4  2  11.6   6.4 |  22.1  71.8  115   3  2  10.6   5.8
  5750  21.6  70.9  160   4  2  10.0   5.5 |  22.9  73.2  110   3  2   9.7   5.3
  5500  22.3  72.1  160   4  2  14.7   8.1 |  23.6  74.5  100   3  1   9.7   5.3
________________________________________________________________________________

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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