Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 171317
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0717 MDT Thursday, April 17, 2014

This forecast is for Thursday, April 17, 2014:

If the trigger temperature of 52.6 F/11.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1161 ft/min (5.9 m/s)
   Maximum height of thermals.................. 17996 ft MSL (12711 ft AGL)

Forecast maximum temperature................... 63.0 F/17.7 C
Time of trigger temperature.................... 1045 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................. 14181 ft MSL (8895 ft AGL)
Thermal soaring outlook for Friday 04/18....... Excellent

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 16865 ft MSL (11580 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 34112 ft MSL (28827 ft AGL)
Wave soaring outlook for Friday 04/18.......... Fair

Remarks...

Sunrise/Sunset.................... 06:18:59 / 19:38:46 MDT
Total possible sunshine........... 13 hr 19 min 46 sec (799 min 46 sec)
Altitude of sun at 12:59:02 MDT... 60.88 degrees

Upper air data from rawinsonde observation taken on 04/17/2014 at 0600 MDT

Freezing level.................. 9007 ft MSL (3722 ft AGL)
Convective condensation level... 12822 ft MSL (7537 ft AGL)
Lifted condensation level....... 14711 ft MSL (9426 ft AGL)
Lifted index.................... -0.2
K index......................... +8.0

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  -56.6 -69.9   295   27   14   1.1   0.6  107.0 224.6    51.1      M    M
 45000  -55.7 -68.3   305   35   18   0.5   0.3   83.5 182.3    40.4      M    M
 40000  -54.7 -66.5   315   39   20  -0.9  -0.5   61.9 143.3    29.1      M    M
 38000  -54.6 -66.3   315   46   24   4.8   2.6   53.2 127.7    24.1      M    M
 36000  -55.9 -68.6   320   54   28  -6.8  -3.7   42.7 108.8    17.5      M    M
 34000  -55.3 -67.5   320   63   32   0.3   0.2   35.2  95.3    12.7      M    M
 32000  -53.0 -63.4   325   61   32   5.7   3.2   29.2  84.6     8.8      M    M
 30000  -50.1 -58.2   330   62   32   8.3   4.6   25.3  77.5     6.0      M    M
 29000  -47.5 -53.5   330   62   32   8.5   4.7   24.9  76.7     5.8      M    M
 28000  -44.9 -48.8   330   58   30   8.5   4.7   24.3  75.7     5.4      M    M
 27000  -42.3 -44.1   330   53   27   8.6   4.7   23.9  74.9     5.2      M    M
 26000  -39.5 -39.1   330   49   25   9.6   5.3   23.7  74.7     5.1      M    M
 25000  -36.6 -33.9   330   45   23   9.6   5.3   23.7  74.7     5.2      M    M
 24000  -33.7 -28.7   330   45   23   9.7   5.3   23.6  74.5     5.2      M    M
 23000  -31.0 -23.8   315   42   21   7.7   4.2   23.3  74.0     5.0      M    M
 22000  -29.3 -20.7   300   39   20   3.9   2.2   21.9  71.4     3.8      M    M
 21000  -28.2 -18.8   305   34   18   3.9   2.2   19.7  67.5     2.0      M    M
 20000  -26.4 -15.5   310   29   15   7.8   4.3   18.4  65.2     1.0      M    M
 19500  -25.2 -13.4   310   28   14   8.0   4.4   18.1  64.6     0.7      M    M
 19000  -24.1 -11.4   305   27   14   8.0   4.4   17.8  64.0     0.4      M    M
 18500  -22.9  -9.2   305   25   13   8.1   4.5   17.5  63.5     0.1      M    M
 18000  -21.5  -6.7   295   24   12   9.4   5.1   17.4  63.2     0.0      M    M
 17500  -20.2  -4.4   300   23   12   8.8   4.9   17.3  63.1    -0.1   1116  5.7
 17000  -19.2  -2.6   305   23   12   3.1   1.7   16.7  62.0    -0.6   1074  5.5
 16500  -18.9  -2.0   310   22   11   3.6   2.0   15.4  59.7    -1.8   1050  5.3
 16000  -17.3   0.9   320   22   11   8.5   4.7   14.8  58.7    -2.3    977  5.0
 15500  -16.0   3.2   315   23   12   8.6   4.7   14.6  58.3    -2.5    924  4.7
 15000  -14.7   5.5   310   23   12   8.6   4.7   14.4  57.9    -2.7    871  4.4
 14500  -13.4   7.9   305   24   12   9.1   5.0   14.2  57.6    -2.9    817  4.2
 14000  -12.4   9.7   300   25   13   4.6   2.5   13.7  56.7    -3.4    774  3.9
 13500  -11.6  11.1   295   23   12   7.5   4.1   13.1  55.5    -4.0    733  3.7
 13000  -10.2  13.6   295   21   11   9.0   4.9   13.0  55.3    -4.2    678  3.4
 12500   -8.9  16.0   300   19   10   9.0   4.9   12.8  55.1    -4.3    622  3.2
 12000   -7.5  18.5   300   17    9   9.0   4.9   12.7  54.9    -4.4    567  2.9
 11500   -6.2  20.8   300   14    7   9.0   4.9   12.6  54.7    -4.6    511  2.6
 11000   -4.8  23.4   305   12    6   9.0   4.9   12.5  54.5    -4.7    456  2.3
 10500   -3.4  25.9   300   10    5   9.0   5.0   12.3  54.2    -4.9    400  2.0
 10250   -2.8  27.0   295    9    5   8.8   4.8   12.3  54.1    -4.9    373  1.9
 10000   -2.1  28.2   285    9    5   8.1   4.4   12.2  53.9    -5.0    346  1.8
  9750   -1.6  29.1   275    9    4   7.8   4.3   12.0  53.6    -5.2    322  1.6
  9500   -1.0  30.2   265    9    5   8.0   4.4   11.9  53.4    -5.4    297  1.5
  9250   -0.4  31.3   255    9    5   7.7   4.2   11.7  53.1    -5.6    273  1.4
  9000    0.0  32.0   245   10    5   4.5   2.5   11.5  52.7    -5.8    251  1.3
  8750    0.2  32.4   245   12    6   2.5   1.4   10.9  51.7    -6.4    239  1.2
  8500    0.4  32.7   240   13    7   2.9   1.6   10.4  50.7    -7.0    226  1.1
  8250    0.6  33.1   240   15    7   3.4   1.9    9.9  49.8    -7.5    213  1.1
  8000    0.9  33.6   240   16    8   4.2   2.3    9.5  49.0    -8.0    197  1.0
  7750    1.1  34.0   235   16    8   4.0   2.2    9.0  48.2    -8.5    181  0.9
  7500    1.4  34.5   230   16    8   4.1   2.2    8.6  47.4    -9.0    166  0.8
  7250    1.7  35.1   225   17    9   4.2   2.3    8.1  46.7    -9.4    150  0.8
  7000    2.0  35.6   220   17    9   3.9   2.1    7.7  45.9    -9.9    134  0.7
  6750    2.3  36.1   215   18    9   4.9   2.7    7.3  45.1   -10.4    118  0.6
  6500    2.6  36.7   215   18    9   1.1   0.6    6.9  44.3   -10.9    102  0.5
  6250    2.4  36.3   210   19   10  -3.1  -1.7    6.0  42.7   -11.8    100  0.5
  6000    2.3  36.1   210   20   10   0.7   0.4    5.1  41.2   -12.7     97  0.5
  5750    2.4  36.3   210   15    8   3.5   1.9    4.6  40.2   -13.3     84  0.4
  5500    2.6  36.7   220    9    5   0.5   0.3    4.0  39.2   -13.8     70  0.4

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

           04/17/2014 at 0900 MDT          |       04/17/2014 at 1200 MDT
                                           |
K index... +7.2  LI... +3.0                | K index... +5.0  LI... +2.5
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -57.5 -71.5  300  30 15   0.4   0.2 | -57.3 -71.1  300  28 14  -0.3  -0.2
 45000 -56.9 -70.4  310  39 20   0.6   0.3 | -57.8 -72.0  315  37 19  -0.2  -0.1
 40000 -58.7 -73.7  325  55 29  -1.3  -0.7 | -60.8 -77.4  330  58 30  -2.0  -1.1
 38000 -58.8 -73.8  335  65 33   2.1   1.2 | -60.2 -76.4  330  63 32   4.4   2.4
 36000 -57.5 -71.5  340  79 40   2.1   1.2 | -57.5 -71.5  335  65 33   4.4   2.4
 34000 -56.2 -69.2  345  93 48   5.2   2.9 | -54.6 -66.3  340  66 34   8.5   4.7
 32000 -51.0 -59.8  340  85 44   7.6   4.2 | -49.8 -57.6  335  65 34   8.1   4.4
 30000 -46.5 -51.7  335  78 40   7.4   4.1 | -45.0 -49.0  330  64 33   7.2   3.9
 29000 -44.2 -47.6  335  74 38   7.4   4.1 | -42.8 -45.0  330  61 32   7.3   4.0
 28000 -42.0 -43.6  335  69 36   7.4   4.1 | -40.1 -40.2  325  59 30   7.3   4.0
 27000 -39.8 -39.6  335  65 33   7.5   4.1 | -37.9 -36.2  325  56 29   7.5   4.1
 26000 -37.5 -35.5  330  59 30   7.8   4.3 | -35.6 -32.1  325  54 28   7.7   4.2
 25000 -35.1 -31.2  330  54 28   7.8   4.3 | -33.3 -27.9  325  52 27   7.7   4.2
 24000 -32.8 -27.0  325  48 25   7.8   4.3 | -31.0 -23.8  325  50 26   7.7   4.2
 23000 -30.4 -22.7  325  45 23   8.0   4.4 | -28.7 -19.7  325  47 24   7.7   4.2
 22000 -28.0 -18.4  325  42 22   8.0   4.4 | -26.4 -15.5  320  44 23   7.7   4.2
 21000 -25.6 -14.1  320  39 20   6.7   3.7 | -24.2 -11.6  315  42 22   6.1   3.3
 20000 -24.0 -11.2  320  37 19   5.3   2.9 | -22.5  -8.5  315  39 20   5.7   3.1
 19500 -23.2  -9.8  320  36 18   5.3   2.9 | -21.6  -6.9  315  38 19   5.7   3.1
 19000 -22.4  -8.3  320  35 18   5.3   2.9 | -20.8  -5.4  315  36 19   5.7   3.1
 18500 -21.6  -6.9  320  34 17   5.5   3.0 | -19.9  -3.8  315  35 18   6.0   3.3
 18000 -20.8  -5.4  320  32 17   6.0   3.3 | -19.0  -2.2  315  33 17   6.2   3.4
 17500 -19.9  -3.8  320  31 16   5.8   3.2 | -18.1  -0.6  315  31 16   6.1   3.4
 17000 -18.9  -2.0  320  30 15   7.9   4.3 | -17.2   1.0  315  29 15   5.7   3.1
 16500 -17.7   0.1  320  28 15   7.8   4.3 | -16.3   2.7  315  27 14   5.7   3.1
 16000 -16.1   3.0  320  26 14   6.9   3.8 | -15.4   4.3  310  25 13   6.6   3.6
 15500 -15.0   5.0  315  25 13   7.0   3.8 | -14.5   5.9  310  23 12   6.6   3.6
 15000 -14.0   6.8  315  24 12   6.9   3.8 | -13.5   7.7  305  21 11   6.8   3.8
 14500 -13.0   8.6  315  22 11   6.8   3.7 | -12.5   9.5  305  20 10   7.0   3.8
 14000 -11.9  10.6  315  20 10   8.3   4.6 | -10.8  12.6  300  18  9   8.1   4.4
 13500 -10.6  12.9  315  18 10   8.5   4.7 |  -9.7  14.5  295  17  9   8.0   4.4
 13000  -9.3  15.3  315  17  9   8.8   4.8 |  -8.4  16.9  295  16  8   8.6   4.7
 12500  -8.0  17.6  315  16  8   8.9   4.9 |  -7.1  19.2  295  15  8   8.7   4.8
 12000  -6.7  19.9  315  14  7   9.0   4.9 |  -5.9  21.4  295  14  7   8.1   4.4
 11500  -5.3  22.5  315  13  7   9.0   4.9 |  -4.7  23.5  295  12  6   8.0   4.4
 11000  -4.0  24.8  315  12  6   7.9   4.4 |  -3.5  25.7  295  11  5   7.8   4.3
 10500  -2.9  26.8  315  11  6   8.3   4.5 |  -2.4  27.7  300   9  4   8.4   4.6
 10250  -2.4  27.7  315  10  5   4.6   2.5 |  -1.8  28.8  300   8  4   5.1   2.8
 10000  -2.2  28.0  310  10  5   4.8   2.7 |  -1.5  29.3  300   7  4   6.0   3.3
  9750  -1.6  29.1  310   9  5   8.9   4.9 |  -0.9  30.4  295   6  3   9.8   5.4
  9500  -0.9  30.4  305   8  4   8.5   4.7 |  -0.2  31.6  290   5  2   9.5   5.2
  9250  -0.3  31.5  305   6  3   7.1   3.9 |   0.5  32.9  280   4  2   6.9   3.8
  9000   0.1  32.2  300   5  3   5.2   2.8 |   0.9  33.6  260   3  1   5.4   3.0
  8750   0.5  32.9  295   4  2   5.7   3.1 |   1.4  34.5  230   2  1   8.0   4.4
  8500   0.9  33.6  285   3  2   5.8   3.2 |   2.0  35.6  205   3  1   8.0   4.4
  8250   1.3  34.3  265   2  1   5.7   3.1 |   2.5  36.5  190   3  2   7.7   4.2
  8000   1.7  35.1  245   2  1   5.6   3.1 |   3.0  37.4  180   3  2   7.9   4.3
  7750   2.2  36.0  230   2  1   5.8   3.2 |   3.6  38.5  170   3  1   8.8   4.8
  7500   2.6  36.7  225   3  1   5.4   3.0 |   4.3  39.7  165   3  1   9.7   5.3
  7250   2.9  37.2  220   3  2   4.5   2.5 |   5.0  41.0  165   3  1  10.1   5.6
  7000   3.2  37.8  220   4  2   4.5   2.4 |   5.8  42.4  165   2  1  10.1   5.5
  6750   3.5  38.3  220   4  2   4.3   2.4 |   6.5  43.7  165   2  1   9.8   5.4
  6500   3.8  38.8  215   4  2   4.4   2.4 |   7.2  45.0  165   2  1  10.5   5.7
  6250   4.1  39.4  210   4  2   5.3   2.9 |   8.1  46.6  170   2  1  11.8   6.4
  6000   4.5  40.1  205   4  2   3.1   1.7 |   8.9  48.0  170   2  1   9.6   5.3
  5750   4.6  40.3  200   4  2   6.8   3.7 |   9.6  49.3  170   2  1  14.1   7.7
  5500   5.6  42.1  195   4  2  19.9  10.9 |  11.2  52.2  170   2  1  27.4  15.0

           04/17/2014 at 1500 MDT          |       04/17/2014 at 1800 MDT
                                           |
K index... +11.1  LI... +2.8               | K index... +11.2  LI... +2.7
CAPE... 0.0  CIN... M                      | 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 -58.2 -72.8  305  24 12  -0.2  -0.1 | -59.7 -75.5  310  27 14  -0.6  -0.3
 45000 -58.5 -73.3  315  33 17   0.1   0.1 | -60.6 -77.1  315  33 17  -0.7  -0.4
 40000 -62.5 -80.5  330  55 28  -2.6  -1.4 | -65.1 -85.2  340  44 23  -3.0  -1.6
 38000 -61.4 -78.5  335  60 31   6.1   3.3 | -63.1 -81.6  335  46 24   8.1   4.5
 36000 -57.7 -71.9  340  61 31   6.1   3.3 | -58.2 -72.8  330  44 23   8.2   4.5
 34000 -53.8 -64.8  340  61 32   8.7   4.8 | -53.2 -63.8  325  44 23   9.0   4.9
 32000 -48.6 -55.5  335  61 32   8.6   4.7 | -47.7 -53.9  325  45 23   9.0   5.0
 30000 -43.6 -46.5  330  61 31   7.5   4.1 | -42.5 -44.5  320  45 23   8.3   4.6
 29000 -40.8 -41.4  330  59 31   7.6   4.2 | -39.4 -38.9  320  46 24   8.3   4.6
 28000 -38.5 -37.3  330  58 30   7.6   4.2 | -36.9 -34.4  325  46 24   8.3   4.6
 27000 -36.2 -33.2  330  56 29   7.5   4.1 | -34.5 -30.1  325  46 23   7.0   3.8
 26000 -34.0 -29.2  325  53 27   7.5   4.1 | -32.3 -26.1  320  43 22   7.2   3.9
 25000 -31.8 -25.2  325  50 26   7.5   4.1 | -30.2 -22.4  320  40 21   7.2   3.9
 24000 -29.5 -21.1  320  47 24   7.6   4.2 | -28.0 -18.4  315  37 19   7.5   4.1
 23000 -27.2 -17.0  320  45 23   7.7   4.2 | -25.8 -14.4  315  36 19   7.6   4.2
 22000 -24.9 -12.8  320  42 22   7.7   4.2 | -23.5 -10.3  315  35 18   7.6   4.2
 21000 -22.7  -8.9  315  39 20   6.7   3.7 | -21.3  -6.3  310  34 17   7.5   4.1
 20000 -20.7  -5.3  310  38 20   6.7   3.7 | -19.0  -2.2  310  34 17   7.5   4.1
 19500 -19.7  -3.5  310  37 19   6.7   3.7 | -17.9  -0.2  310  34 17   7.5   4.1
 19000 -18.7  -1.7  305  37 19   6.7   3.7 | -16.8   1.8  310  34 17   7.5   4.1
 18500 -17.8  -0.0  300  36 19   5.4   2.9 | -15.7   3.7  310  33 17   6.9   3.8
 18000 -17.0   1.4  300  34 18   4.9   2.7 | -14.7   5.5  305  33 17   6.8   3.7
 17500 -16.3   2.7  300  32 17   5.1   2.8 | -13.7   7.3  305  33 17   6.6   3.6
 17000 -15.4   4.3  295  30 16   6.5   3.6 | -12.8   9.0  305  32 16   5.8   3.2
 16500 -14.5   5.9  295  29 15   6.4   3.5 | -11.9  10.6  300  31 16   5.9   3.2
 16000 -13.5   7.7  290  27 14   6.9   3.8 | -11.1  12.0  295  30 15   5.5   3.0
 15500 -12.5   9.5  290  26 14   6.9   3.8 | -10.3  13.5  290  28 15   5.5   3.0
 15000 -11.5  11.3  285  25 13   7.4   4.1 |  -9.5  14.9  280  28 14   6.1   3.3
 14500  -9.8  14.4  275  23 12   7.7   4.2 |  -8.1  17.4  270  26 13   6.2   3.4
 14000  -8.7  16.3  265  22 11   7.2   4.0 |  -7.1  19.2  265  25 13   7.4   4.1
 13500  -7.6  18.3  260  21 11   7.3   4.0 |  -6.1  21.0  260  22 12   7.3   4.0
 13000  -6.6  20.1  250  19 10   7.4   4.1 |  -5.0  23.0  260  20 10   7.7   4.2
 12500  -5.5  22.1  245  16  8   7.4   4.1 |  -3.8  25.2  260  18  9   7.7   4.2
 12000  -4.4  24.1  235  14  7   7.2   4.0 |  -2.7  27.1  260  16  8   8.3   4.6
 11500  -3.3  26.1  225  12  6   7.2   3.9 |  -1.4  29.5  255  13  7   8.6   4.7
 11000  -2.3  27.9  215  10  5   7.6   4.2 |  -0.3  31.5  245  11  6   6.5   3.6
 10500  -1.1  30.0  205   9  5   8.3   4.5 |   0.6  33.1  230   8  4   6.7   3.7
 10250  -0.6  30.9  200   9  4   5.2   2.8 |   1.0  33.8  220   8  4   4.0   2.2
 10000  -0.3  31.5  200   8  4   6.8   3.8 |   1.3  34.3  215   7  4   6.5   3.6
  9750   0.5  32.9  195   8  4  10.9   6.0 |   2.0  35.6  210   7  3  10.7   5.8
  9500   1.2  34.2  190   7  4  10.5   5.8 |   2.8  37.0  200   6  3  10.2   5.6
  9250   2.0  35.6  185   7  4   8.1   4.4 |   3.5  38.3  195   6  3   8.0   4.4
  9000   2.5  36.5  185   7  3   7.7   4.2 |   4.0  39.2  190   6  3   7.6   4.2
  8750   3.2  37.8  185   7  3  10.8   6.0 |   4.7  40.5  190   6  3  10.2   5.6
  8500   4.0  39.2  185   6  3  10.5   5.7 |   5.4  41.7  185   6  3   9.6   5.3
  8250   4.8  40.6  185   6  3   9.7   5.3 |   6.1  43.0  185   6  3  10.1   5.5
  8000   5.5  41.9  185   6  3   9.4   5.1 |   6.9  44.4  185   6  3  10.2   5.6
  7750   6.2  43.2  185   6  3  10.3   5.6 |   7.6  45.7  185   5  3   9.9   5.5
  7500   7.0  44.6  185   6  3  10.3   5.6 |   8.4  47.1  185   5  3   9.8   5.4
  7250   7.7  45.9  185   6  3   9.9   5.5 |   9.1  48.4  185   5  3   9.7   5.3
  7000   8.5  47.3  185   6  3   9.9   5.4 |   9.8  49.6  185   5  3   9.7   5.3
  6750   9.2  48.6  185   6  3  10.0   5.5 |  10.5  50.9  190   5  2   9.4   5.1
  6500  10.0  50.0  185   5  3  10.7   5.9 |  11.2  52.2  190   5  2  10.0   5.5
  6250  10.8  51.4  185   5  3  11.6   6.4 |  12.0  53.6  190   5  2  10.9   6.0
  6000  11.6  52.9  185   5  3  10.1   5.6 |  12.8  55.0  190   4  2  10.2   5.6
  5750  12.4  54.3  185   5  2  13.1   7.2 |  13.6  56.5  190   4  2  10.6   5.8
  5500  13.7  56.7  185   5  2  23.2  12.7 |  14.4  57.9  190   4  2  13.7   7.5
________________________________________________________________________________

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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