Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 141238
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0638 MDT Sunday, September 14, 2014

This forecast is for Sunday, September 14, 2014:

If the trigger temperature of 78.6 F/25.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1487 ft/min (7.6 m/s)
   Maximum height of thermals.................. 20362 ft MSL (15077 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 16360 ft MSL (11075 ft AGL)
Thermal soaring outlook for Monday 09/15....... Poor

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 16592 ft MSL (11307 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 17084 ft MSL (11799 ft AGL)
Wave soaring outlook for Monday 09/15.......... Fair

Remarks...

Sunrise/Sunset.................... 06:39:37 / 19:11:11 MDT
Total possible sunshine........... 12 hr 31 min 35 sec (751 min 35 sec)
Altitude of sun at 12:54:55 MDT... 53.46 degrees

Upper air data from rawinsonde observation taken on 09/14/2014 at 0600 MDT

Freezing level.................. 14131 ft MSL (8846 ft AGL)
Convective condensation level... 18292 ft MSL (13007 ft AGL)
Lifted condensation level....... 18954 ft MSL (13668 ft AGL)
Lifted index.................... +2.5
K index......................... +15.0

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  -66.0 -86.8   275   49   25   1.0   0.6   85.0 185.0    31.8      M    M
 45000  -61.3 -78.3   265   77   40   8.2   4.5   68.1 154.5    23.6      M    M
 40000  -52.8 -63.0   270   86   44   1.4   0.8   57.6 135.8    18.4      M    M
 38000  -50.8 -59.4   265   73   38   6.7   3.7   52.0 125.6    15.1      M    M
 36000  -47.9 -54.2   260   60   31   2.7   1.5   47.8 118.0    12.5      M    M
 34000  -45.0 -49.0   265   50   26   8.8   4.8   43.5 110.4     9.7      M    M
 32000  -39.6 -39.3   265   45   23   9.1   5.0   42.9 109.3     9.5      M    M
 30000  -35.0 -31.0   265   44   23   8.3   4.5   41.3 106.3     8.5      M    M
 29000  -31.9 -25.4   270   42   22   6.7   3.7   40.6 105.0     8.1      M    M
 28000  -29.7 -21.5   270   41   21   9.4   5.2   39.7 103.5     7.5      M    M
 27000  -26.9 -16.4   270   40   21   9.1   5.0   39.4 103.0     7.4      M    M
 26000  -24.2 -11.6   275   39   20   9.2   5.0   39.2 102.6     7.3      M    M
 25000  -21.4  -6.5   275   36   19   8.9   4.9   39.0 102.2     7.2      M    M
 24000  -19.2  -2.6   275   34   17   7.9   4.3   38.1 100.6     6.6      M    M
 23000  -16.8   1.8   270   30   16   7.7   4.2   37.4  99.3     6.1      M    M
 22000  -15.1   4.8   265   27   14 -13.5  -7.4   36.0  96.8     5.0      M    M
 21000  -16.0   3.2   280   21   11   5.0   2.8   31.5  88.7     1.2      M    M
 20000  -14.7   5.5   275   19   10   9.5   5.2   29.7  85.5    -0.4   1459  7.4
 19500  -13.5   7.7   270   18    9   8.4   4.6   29.5  85.0    -0.6   1407  7.1
 19000  -12.2  10.0   270   18    9   8.3   4.5   29.2  84.6    -0.8   1356  6.9
 18500  -11.0  12.2   270   16    8   8.3   4.5   29.0  84.1    -1.1   1305  6.6
 18000   -9.8  14.4   270   15    8   8.3   4.5   28.7  83.7    -1.3   1254  6.4
 17500   -8.6  16.5   275   16    8   8.3   4.6   28.5  83.2    -1.6   1202  6.1
 17000   -7.4  18.7   285   17    9   8.4   4.6   28.2  82.8    -1.9   1151  5.8
 16500   -6.4  20.5   290   18    9   2.6   1.4   27.8  82.0    -2.3   1106  5.6
 16000   -5.8  21.6   295   20   10   9.9   5.4   26.9  80.5    -3.2   1074  5.5
 15500   -4.3  24.3   295   21   11   9.7   5.3   26.9  80.4    -3.3   1016  5.2
 15000   -2.9  26.8   295   21   11   9.6   5.3   26.9  80.4    -3.3    958  4.9
 14500   -0.7  30.7   295   22   12   9.6   5.3   26.9  80.4    -3.3    871  4.4
 14000    0.7  33.3   295   23   12   9.6   5.3   26.9  80.5    -3.3    813  4.1
 13500    2.2  36.0   295   21   11   9.6   5.3   26.9  80.4    -3.4    755  3.8
 13000    3.6  38.5   295   20   10   9.6   5.3   26.8  80.3    -3.4    697  3.5
 12500    5.0  41.0   295   19   10   9.6   5.3   26.8  80.3    -3.5    639  3.2
 12000    6.5  43.7   295   18    9   9.5   5.2   26.8  80.3    -3.5    581  3.0
 11500    7.9  46.2   295   17    9   9.5   5.2   26.8  80.2    -3.6    524  2.7
 11000    9.3  48.7   290   15    8   9.5   5.2   26.7  80.1    -3.6    466  2.4
 10500   10.8  51.4   290   14    7   9.4   5.1   26.7  80.1    -3.6    408  2.1
 10250   11.4  52.5   290   14    7   9.0   4.9   26.7  80.0    -3.7    380  1.9
 10000   12.1  53.8   290   13    7   8.9   4.9   26.6  79.9    -3.7    353  1.8
  9750   12.8  55.0   285   13    7   8.9   4.9   26.6  79.8    -3.8    326  1.7
  9500   13.4  56.1   285   13    7   8.9   4.9   26.5  79.7    -3.9    298  1.5
  9250   14.1  57.4   280   14    7   8.9   4.9   26.4  79.6    -3.9    271  1.4
  9000   14.8  58.6   280   14    7   8.9   4.9   26.4  79.5    -4.0    244  1.2
  8750   15.4  59.7   275   15    7   8.9   4.9   26.3  79.4    -4.1    216  1.1
  8500   16.1  61.0   275   15    8   8.9   4.9   26.3  79.3    -4.2    189  1.0
  8250   16.8  62.2   270   15    8   8.9   4.9   26.2  79.1    -4.2    162  0.8
  8000   17.4  63.3   270   16    8   8.9   4.9   26.1  79.0    -4.3    134  0.7
  7750   18.1  64.6   270   15    8   9.1   5.0   26.1  78.9    -4.4    107  0.5
  7500   18.8  65.8   270   15    8   8.4   4.6   26.0  78.8    -4.5     80  0.4
  7250   19.4  66.9   265   14    7  11.0   6.0   25.9  78.6    -4.6     52  0.3
  7000   20.1  68.2   265   14    7   1.3   0.7   25.9  78.5    -4.6     25  0.1
  6750   19.5  67.1   255   13    7 -10.6  -5.8   24.6  76.2    -6.0     35  0.2
  6500   18.7  65.7   240   13    7 -10.9  -6.0   23.0  73.5    -7.5     52  0.3
  6250   17.9  64.2   230   13    7  -7.2  -3.9   21.5  70.8    -9.1     69  0.4
  6000   17.4  63.3   215   14    7  -7.9  -4.3   20.4  68.7   -10.3     76  0.4
  5750   16.4  61.5   215   10    5 -15.9  -8.7   18.7  65.6   -12.1     99  0.5
  5500   14.5  58.1   215    5    2 -40.6 -22.3   16.1  61.0   -14.7    149  0.8

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

           09/14/2014 at 0900 MDT          |       09/14/2014 at 1200 MDT
                                           |
K index... +19.3  LI... -0.4               | K index... +13.3  LI... -0.7
CAPE... 0.0  CIN... -19.9                  | CAPE... +27.4  CIN... -54.0
                                           |
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 -64.9 -84.8  275  58 30   1.9   1.1 | -64.2 -83.6  275  57 29   2.3   1.2
 45000 -60.9 -77.6  275  81 42   5.3   2.9 | -60.2 -76.4  275  79 40   4.4   2.4
 40000 -52.7 -62.9  270  89 46   3.7   2.0 | -53.3 -63.9  265  87 45   3.8   2.1
 38000 -50.4 -58.7  270  75 39   3.8   2.1 | -51.0 -59.8  270  75 38   3.8   2.1
 36000 -48.1 -54.6  270  62 32   3.9   2.1 | -48.8 -55.8  270  63 32   3.8   2.1
 34000 -44.5 -48.1  270  53 27   7.1   3.9 | -45.0 -49.0  270  55 28   7.5   4.1
 32000 -40.2 -40.4  270  46 24   7.1   3.9 | -40.5 -40.9  270  49 25   7.5   4.1
 30000 -35.3 -31.5  275  41 21   8.8   4.8 | -35.8 -32.4  270  44 23   8.1   4.5
 29000 -32.1 -25.8  275  39 20   8.8   4.8 | -32.7 -26.9  270  41 21   8.1   4.5
 28000 -29.5 -21.1  280  38 19   8.5   4.7 | -30.3 -22.5  270  39 20   8.3   4.6
 27000 -27.0 -16.6  280  35 18   8.1   4.4 | -27.7 -17.9  270  36 19   8.6   4.7
 26000 -24.6 -12.3  275  32 16   8.1   4.4 | -25.2 -13.4  270  34 17   8.6   4.7
 25000 -22.2  -8.0  270  29 15   8.4   4.6 | -22.6  -8.7  270  31 16   9.0   4.9
 24000 -20.3  -4.5  275  28 14   5.5   3.0 | -20.8  -5.4  275  31 16   5.2   2.8
 23000 -18.7  -1.7  280  28 14   5.5   3.0 | -19.2  -2.6  280  32 16   5.2   2.8
 22000 -17.1   1.2  285  28 14   5.5   3.0 | -17.7   0.1  290  33 17   5.2   2.8
 21000 -15.5   4.1  285  28 14   5.4   3.0 | -15.7   3.7  290  32 17   7.0   3.8
 20000 -13.9   7.0  285  27 14   5.5   3.0 | -13.7   7.3  290  31 16   7.0   3.8
 19500 -13.1   8.4  285  27 14   5.3   2.9 | -12.6   9.3  295  30 16   6.9   3.8
 19000 -12.2  10.0  285  27 14   8.2   4.5 | -11.5  11.3  295  30 15   8.7   4.8
 18500 -10.9  12.4  285  25 13   8.7   4.8 | -10.2  13.6  295  29 15   8.9   4.9
 18000  -9.7  14.5  285  24 12   8.8   4.8 |  -8.9  16.0  295  28 15   8.9   4.9
 17500  -8.4  16.9  290  24 12   8.7   4.8 |  -7.6  18.3  295  28 14   8.6   4.7
 17000  -7.1  19.2  290  24 12   8.8   4.8 |  -6.3  20.7  300  28 14   8.6   4.7
 16500  -5.8  21.6  290  23 12   8.8   4.8 |  -5.0  23.0  300  28 14   8.6   4.7
 16000  -4.5  23.9  290  23 12   8.8   4.8 |  -3.7  25.3  300  27 14   8.6   4.7
 15500  -3.2  26.2  290  22 11   8.9   4.9 |  -2.5  27.5  300  27 14   8.6   4.7
 15000  -1.9  28.6  290  21 11   9.0   4.9 |  -1.2  29.8  300  26 14   8.7   4.8
 14500   0.1  32.2  290  19 10   9.2   5.1 |   0.7  33.3  300  25 13   8.8   4.8
 14000   1.5  34.7  285  17  9   9.3   5.1 |   2.0  35.6  300  24 12   8.9   4.9
 13500   2.8  37.0  285  16  8   9.1   5.0 |   3.3  37.9  300  22 12   9.1   5.0
 13000   4.2  39.6  285  15  8   9.0   4.9 |   4.7  40.5  300  22 12   9.3   5.1
 12500   5.5  41.9  285  14  7   9.1   5.0 |   6.0  42.8  300  22 12   9.1   5.0
 12000   6.9  44.4  285  13  7   9.3   5.1 |   7.3  45.1  300  22 11   8.9   4.9
 11500   8.3  46.9  285  12  6   9.3   5.1 |   8.6  47.5  300  21 11   8.9   4.9
 11000   9.7  49.5  285  13  6   9.0   4.9 |  10.0  50.0  295  19 10   8.7   4.8
 10500  11.1  52.0  290  13  7   5.1   2.8 |  11.3  52.3  295  18  9   4.4   2.4
 10250  11.3  52.3  290  13  7   6.5   3.6 |  11.4  52.5  295  17  9   5.7   3.1
 10000  12.2  54.0  290  13  7  12.6   6.9 |  12.2  54.0  295  16  8  12.2   6.7
  9750  13.1  55.6  290  13  7  11.5   6.3 |  13.0  55.4  290  16  8  10.9   6.0
  9500  13.9  57.0  285  12  6   9.9   5.4 |  13.8  56.8  290  15  8   9.8   5.4
  9250  14.5  58.1  285  12  6   7.3   4.0 |  14.5  58.1  285  14  7   8.1   4.4
  9000  15.1  59.2  285  12  6   9.0   4.9 |  15.1  59.2  285  13  7   9.4   5.1
  8750  15.9  60.6  285  12  6  10.3   5.6 |  15.8  60.4  285  13  7  10.2   5.6
  8500  16.6  61.9  285  12  6   8.7   4.8 |  16.5  61.7  280  12  6   9.1   5.0
  8250  17.2  63.0  285  12  6   7.3   4.0 |  17.1  62.8  280  12  6   8.2   4.5
  8000  17.8  64.0  280  12  6   7.7   4.2 |  17.8  64.0  280  11  6   8.4   4.6
  7750  18.4  65.1  280  12  6   7.7   4.2 |  18.4  65.1  275  11  6   8.4   4.6
  7500  18.9  66.0  280  11  6   5.4   3.0 |  19.0  66.2  275  10  5   8.9   4.9
  7250  19.2  66.6  280  10  5   3.7   2.0 |  19.7  67.5  270  10  5   9.5   5.2
  7000  19.5  67.1  280   9  5   4.4   2.4 |  20.4  68.7  265   9  5   8.7   4.8
  6750  19.7  67.5  280   8  4  -0.1  -0.0 |  21.1  70.0  265   9  5   8.3   4.6
  6500  19.4  66.9  275   7  4  -5.9  -3.2 |  21.7  71.1  260   8  4   9.3   5.1
  6250  18.8  65.8  270   7  3  -8.6  -4.7 |  22.4  72.3  255   7  3  10.2   5.6
  6000  18.3  64.9  260   6  3  -2.4  -1.3 |  23.1  73.6  250   5  3   8.7   4.8
  5750  18.2  64.8  255   6  3  -6.4  -3.5 |  23.8  74.8  245   5  2  12.2   6.7
  5500  16.6  61.9  235   5  3 -29.5 -16.2 |  25.0  77.0  245   4  2  21.8  12.0

           09/14/2014 at 1500 MDT          |       09/14/2014 at 1800 MDT
                                           |
K index... +19.1  LI... -2.0               | K index... +23.7  LI... -2.3
CAPE... +141.1  CIN... -37.1               | CAPE... +334.7  CIN... -32.2
                                           |
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 -64.1 -83.4  275  53 27   3.0   1.6 | -64.0 -83.2  275  47 24   3.2   1.8
 45000 -59.3 -74.7  270  74 38   3.1   1.7 | -59.2 -74.6  275  66 34   2.5   1.4
 40000 -54.5 -66.1  270  76 39   4.7   2.6 | -55.2 -67.4  270  71 37   5.2   2.9
 38000 -51.7 -61.1  270  69 35   4.7   2.6 | -52.1 -61.8  270  65 33   5.3   2.9
 36000 -48.8 -55.8  270  62 32   4.8   2.6 | -48.9 -56.0  275  59 30   5.4   2.9
 34000 -44.8 -48.6  275  57 29   7.6   4.1 | -44.7 -48.5  275  54 28   7.6   4.2
 32000 -40.3 -40.5  275  53 27   7.6   4.2 | -40.2 -40.4  280  51 26   7.6   4.2
 30000 -35.2 -31.4  275  48 25   7.6   4.2 | -34.8 -30.6  280  48 25   8.1   4.5
 29000 -32.9 -27.2  275  46 24   7.6   4.2 | -32.4 -26.3  280  46 24   8.1   4.5
 28000 -30.6 -23.1  275  44 23   7.9   4.3 | -30.0 -22.0  285  45 23   8.0   4.4
 27000 -28.1 -18.6  275  42 22   8.5   4.6 | -27.6 -17.7  285  44 23   7.8   4.3
 26000 -25.5 -13.9  275  41 21   8.5   4.7 | -25.3 -13.5  285  42 22   7.8   4.3
 25000 -23.0  -9.4  275  39 20   8.6   4.7 | -23.0  -9.4  285  41 21   8.0   4.4
 24000 -20.8  -5.4  280  36 19   7.0   3.8 | -21.0  -5.8  285  38 19   6.5   3.6
 23000 -18.7  -1.7  280  33 17   7.0   3.8 | -19.0  -2.2  285  34 17   6.5   3.6
 22000 -16.6   2.1  285  29 15   7.0   3.9 | -17.1   1.2  285  30 15   6.6   3.6
 21000 -14.8   5.4  290  29 15   5.6   3.1 | -15.0   5.0  285  29 15   7.3   4.0
 20000 -13.2   8.2  290  29 15   5.7   3.1 | -12.8   9.0  285  28 14   7.3   4.0
 19500 -12.3   9.9  295  29 15   5.5   3.0 | -11.7  10.9  285  27 14   7.2   4.0
 19000 -11.3  11.7  295  29 15   9.2   5.1 | -10.6  12.9  285  27 14   9.1   5.0
 18500  -9.9  14.2  295  29 15   9.8   5.4 |  -9.2  15.4  285  27 14   9.3   5.1
 18000  -8.4  16.9  295  29 15   9.8   5.4 |  -7.8  18.0  290  26 13   9.2   5.0
 17500  -7.0  19.4  295  29 15   9.3   5.1 |  -6.5  20.3  285  26 13   8.3   4.6
 17000  -5.6  21.9  295  28 15   9.4   5.2 |  -5.3  22.5  285  25 13   8.3   4.6
 16500  -4.3  24.3  295  28 14   9.0   4.9 |  -4.1  24.6  285  24 12   9.0   4.9
 16000  -3.0  26.6  295  28 14   9.0   4.9 |  -2.7  27.1  285  23 12   9.1   5.0
 15500  -1.7  28.9  295  28 14   9.0   4.9 |  -1.4  29.5  285  22 12   9.1   5.0
 15000   0.3  32.5  295  26 14   9.1   5.0 |   0.6  33.1  285  20 10   9.1   5.0
 14500   1.6  34.9  290  26 13   9.0   4.9 |   2.0  35.6  285  19 10   9.7   5.3
 14000   2.9  37.2  290  24 13   9.0   5.0 |   3.4  38.1  285  18  9   9.9   5.4
 13500   4.2  39.6  285  23 12   9.2   5.1 |   4.9  40.8  285  17  9   9.7   5.3
 13000   5.6  42.1  285  21 11   9.3   5.1 |   6.3  43.3  285  16  8   9.5   5.2
 12500   6.9  44.4  285  20 10   9.2   5.0 |   7.7  45.9  285  15  8   9.4   5.2
 12000   8.2  46.8  280  18  9   8.8   4.8 |   9.1  48.4  285  14  7   9.3   5.1
 11500   9.5  49.1  280  17  9   8.9   4.9 |  10.5  50.9  280  13  7   9.2   5.0
 11000  10.9  51.6  275  15  8   8.8   4.8 |  11.8  53.2  280  12  6   8.8   4.8
 10500  12.2  54.0  275  13  7   4.8   2.6 |  13.2  55.8  275  10  5   5.2   2.9
 10250  12.4  54.3  275  13  7   5.6   3.1 |  13.4  56.1  275  10  5   5.9   3.2
 10000  13.2  55.8  270  11  6  11.4   6.3 |  14.2  57.6  270   9  5  11.2   6.1
  9750  13.9  57.0  265  10  5  10.3   5.6 |  14.9  58.8  265   8  4  10.0   5.5
  9500  14.7  58.5  265   9  4   9.0   5.0 |  15.7  60.3  260   7  4   9.4   5.2
  9250  15.2  59.4  255   8  4   7.0   3.9 |  16.3  61.3  255   7  3   8.1   4.4
  9000  15.8  60.4  250   7  3   8.6   4.7 |  16.9  62.4  250   6  3   8.7   4.8
  8750  16.5  61.7  240   6  3   9.3   5.1 |  17.6  63.7  240   6  3   9.3   5.1
  8500  17.2  63.0  230   6  3   9.5   5.2 |  18.2  64.8  230   7  3   8.8   4.9
  8250  17.9  64.2  225   5  3  10.0   5.5 |  18.9  66.0  225   7  4   8.5   4.6
  8000  18.6  65.5  225   5  3   9.9   5.4 |  19.6  67.3  220   7  4   8.2   4.5
  7750  19.4  66.9  225   5  3   9.8   5.4 |  20.1  68.2  215   7  4   7.8   4.3
  7500  20.1  68.2  225   5  3  10.0   5.5 |  20.7  69.3  210   7  4   8.6   4.7
  7250  20.9  69.6  225   5  3  10.3   5.6 |  21.3  70.3  215   7  4   9.4   5.1
  7000  21.6  70.9  225   5  3  10.1   5.6 |  22.0  71.6  215   7  3   9.2   5.1
  6750  22.4  72.3  225   5  3  10.0   5.5 |  22.6  72.7  215   7  3   9.3   5.1
  6500  23.1  73.6  225   5  3  10.1   5.5 |  23.3  73.9  215   7  3   9.8   5.4
  6250  23.9  75.0  225   5  3  10.6   5.8 |  24.1  75.4  215   6  3  10.1   5.5
  6000  24.7  76.5  225   5  3   9.0   4.9 |  24.8  76.6  220   6  3  10.0   5.5
  5750  25.4  77.7  225   5  3  11.8   6.5 |  25.5  77.9  220   6  3   9.0   5.0
  5500  26.6  79.9  225   5  3  22.0  12.1 |  26.1  79.0  220   5  3   7.6   4.1
________________________________________________________________________________

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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