Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 161235
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0635 MDT Wednesday, April 16, 2014

This forecast is for Wednesday, April 16, 2014:

If the trigger temperature of 49.5 F/9.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 456 ft/min (2.3 m/s)
   Maximum height of thermals.................. 11368 ft MSL (6081 ft AGL)

Forecast maximum temperature................... 54.0 F/12.7 C
Time of trigger temperature.................... 1000 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................. 8734 ft MSL (3447 ft AGL)
Thermal soaring outlook for Thursday 04/17..... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Increasing
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 30415 ft MSL (25128 ft AGL)
Wave soaring outlook for Thursday 04/17........ Fair

Remarks... None

Sunrise/Sunset.................... 06:20:27 / 19:37:46 MDT
Total possible sunshine........... 13 hr 17 min 18 sec (797 min 18 sec)
Altitude of sun at 12:59:16 MDT... 60.53 degrees

Upper air data from numerical model forecast valid on 04/16/2014 at 0600 MDT

Freezing level.................. 8260 ft MSL (2973 ft AGL)
Convective condensation level... 14054 ft MSL (8767 ft AGL)
Lifted condensation level....... 12935 ft MSL (7647 ft AGL)
Lifted index.................... +4.6
K index......................... +7.3

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  -56.0 -68.8   290   29   15   3.0   1.6      M     M       M      M    M
 45000  -51.3 -60.3   290   47   24   3.1   1.7      M     M       M      M    M
 40000  -57.6 -71.7   275   52   27  -4.8  -2.6      M     M       M      M    M
 38000  -59.5 -75.1   270   55   28   2.2   1.2      M     M       M      M    M
 36000  -58.1 -72.6   280   55   28   2.3   1.2      M     M       M      M    M
 34000  -56.8 -70.2   285   56   29   2.1   1.1      M     M       M      M    M
 32000  -52.4 -62.3   285   62   32   6.9   3.8      M     M       M      M    M
 30000  -48.2 -54.8   290   66   34   8.6   4.7   27.1  80.8    11.2      M    M
 29000  -45.5 -49.9   285   65   33   8.8   4.8   26.6  79.9    10.9      M    M
 28000  -42.9 -45.2   285   63   33   8.8   4.8   26.2  79.2    10.8      M    M
 27000  -40.3 -40.5   285   62   32   8.8   4.8   26.0  78.8    10.7      M    M
 26000  -37.6 -35.7   285   62   32   8.7   4.8   25.6  78.0    10.5      M    M
 25000  -35.0 -31.0   285   62   32   8.7   4.8   25.1  77.2    10.3      M    M
 24000  -32.4 -26.3   290   63   32   8.7   4.8   24.8  76.6    10.1      M    M
 23000  -30.0 -22.0   290   62   32   7.8   4.3   24.2  75.5     9.7      M    M
 22000  -27.7 -17.9   290   60   31   7.8   4.3   23.4  74.2     9.2      M    M
 21000  -25.3 -13.5   290   58   30   7.8   4.3   22.8  73.1     8.8      M    M
 20000  -23.1  -9.6   290   57   29   7.4   4.0   22.0  71.5     8.2      M    M
 19500  -22.0  -7.6   290   56   29   7.4   4.0   21.5  70.8     7.9      M    M
 19000  -20.9  -5.6   290   55   28   7.4   4.0   21.1  70.0     7.6      M    M
 18500  -19.8  -3.6   290   54   28   7.5   4.1   20.8  69.4     7.3      M    M
 18000  -18.7  -1.7   290   54   28   6.1   3.3   20.3  68.5     6.9      M    M
 17500  -17.8  -0.0   290   53   27   6.1   3.3   19.6  67.3     6.4      M    M
 17000  -16.9   1.6   290   53   27   6.1   3.3   19.0  66.2     5.9      M    M
 16500  -16.0   3.2   290   52   27   6.1   3.3   18.4  65.1     5.3      M    M
 16000  -14.7   5.5   290   51   26   6.4   3.5   17.5  63.4     4.5      M    M
 15500  -13.7   7.3   290   51   26   6.6   3.6   16.9  62.4     4.0      M    M
 15000  -12.8   9.0   290   50   26   6.7   3.7   16.4  61.5     3.6      M    M
 14500  -11.8  10.8   290   49   25   6.8   3.7   15.9  60.6     3.1      M    M
 14000  -10.8  12.6   290   48   25   6.8   3.7   15.4  59.7     2.7      M    M
 13500   -9.8  14.4   290   47   24   6.5   3.6   14.9  58.8     2.2      M    M
 13000   -8.8  16.2   290   46   24   6.6   3.6   14.4  57.9     1.7      M    M
 12500   -7.9  17.8   295   45   23   6.2   3.4   13.8  56.9     1.2      M    M
 12000   -7.0  19.4   295   43   22   6.2   3.4   13.3  55.9     0.6      M    M
 11500   -6.1  21.0   300   41   21   6.1   3.4   12.7  54.8     0.1      M    M
 11000   -5.2  22.6   300   40   20   6.1   3.4   12.1  53.8    -0.5    420  2.1
 10500   -4.3  24.3   300   38   19   5.2   2.9   11.4  52.6    -1.1    381  1.9
 10250   -3.9  25.0   305   36   19   5.2   2.8   11.1  51.9    -1.5    362  1.8
 10000   -3.5  25.7   305   35   18   7.4   4.1   10.8  51.4    -1.7    341  1.7
  9750   -2.9  26.8   305   34   17   7.5   4.1   10.7  51.2    -1.9    316  1.6
  9500   -2.5  27.5   305   32   16   5.9   3.2   10.4  50.7    -2.2    295  1.5
  9250   -2.0  28.4   310   30   15   6.3   3.5   10.1  50.2    -2.4    274  1.4
  9000   -1.5  29.3   310   28   15   6.1   3.4    9.8  49.7    -2.7    252  1.3
  8750   -1.1  30.0   310   26   13   6.9   3.8    9.6  49.2    -3.0    231  1.2
  8500   -0.5  31.1   310   24   13   7.7   4.2    9.4  48.9    -3.2    207  1.1
  8250    0.0  32.0   310   23   12   7.4   4.1    9.2  48.6    -3.4    183  0.9
  8000    0.6  33.1   310   21   11   9.1   5.0    9.1  48.3    -3.5    158  0.8
  7750    1.3  34.3   310   19   10   9.1   5.0    9.1  48.3    -3.5    129  0.7
  7500    1.9  35.4   310   17    9   7.5   4.1    8.9  48.1    -3.7    104  0.5
  7250    2.5  36.5   315   16    8   8.7   4.7    8.8  47.8    -3.9     79  0.4
  7000    3.2  37.8   315   15    8  10.1   5.6    8.8  47.8    -3.9     51  0.3
  6750    4.0  39.2   315   14    7   9.3   5.1    8.8  47.9    -3.9     21  0.1
  6500    4.6  40.3   315   14    7   8.4   4.6    8.7  47.7    -4.0      M    M
  6250    5.2  41.4   320   13    7   5.5   3.0    8.6  47.4    -4.2      M    M
  6000    5.4  41.7   320   11    6   2.7   1.5    8.1  46.5    -4.7      M    M
  5750    5.6  42.1   320    9    5   2.5   1.4    7.6  45.6    -5.2      M    M
  5500    5.3  41.5   320    6    3 -14.4  -7.9    6.6  43.8    -6.2      M    M

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

           04/16/2014 at 0900 MDT          |       04/16/2014 at 1200 MDT
                                           |
K index... -15.7  LI... +5.6               | K index... -7.0  LI... +4.5
CAPE... 0.0  CIN... -1.2                   | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -55.9 -68.6  290  26 13   1.9   1.1 | -55.8 -68.4  275  25 13   1.3   0.7
 45000 -52.9 -63.2  300  40 20   2.1   1.1 | -53.7 -64.7  295  35 18   1.4   0.8
 40000 -56.4 -69.5  280  48 24  -2.7  -1.5 | -55.4 -67.7  290  46 24  -1.3  -0.7
 38000 -57.7 -71.9  275  53 27  -0.5  -0.2 | -56.2 -69.2  290  52 27  -1.3  -0.7
 36000 -57.9 -72.2  275  62 32  -0.4  -0.2 | -57.0 -70.6  285  64 33  -1.3  -0.7
 34000 -58.2 -72.8  280  71 36  -0.6  -0.3 | -57.8 -72.0  280  76 39  -1.6  -0.9
 32000 -53.5 -64.3  280  70 36   8.8   4.8 | -52.5 -62.5  275  74 38   8.7   4.7
 30000 -47.5 -53.5  280  69 36   8.6   4.7 | -47.4 -53.3  275  71 37   8.3   4.5
 29000 -45.0 -49.0  280  68 35   8.5   4.6 | -45.0 -49.0  280  68 35   8.1   4.4
 28000 -42.4 -44.3  285  67 34   8.5   4.6 | -42.5 -44.5  280  66 34   8.1   4.4
 27000 -39.9 -39.8  290  66 34   8.6   4.7 | -40.1 -40.2  280  63 32   8.2   4.5
 26000 -37.6 -35.7  290  64 33   7.3   4.0 | -37.9 -36.2  285  59 31   7.0   3.8
 25000 -35.4 -31.7  290  62 32   7.3   4.0 | -35.8 -32.4  290  56 29   7.0   3.8
 24000 -33.2 -27.8  295  60 31   7.3   4.0 | -33.8 -28.8  295  52 27   7.0   3.8
 23000 -31.0 -23.8  295  59 30   7.5   4.1 | -31.5 -24.7  295  50 26   7.7   4.2
 22000 -28.8 -19.8  295  57 29   7.6   4.1 | -29.2 -20.6  295  49 25   7.7   4.2
 21000 -26.5 -15.7  295  56 29   7.6   4.2 | -26.9 -16.4  300  47 24   7.7   4.2
 20000 -24.2 -11.6  295  54 28   7.8   4.3 | -24.7 -12.5  300  45 23   7.2   4.0
 19500 -23.0  -9.4  295  53 27   7.8   4.3 | -23.6 -10.5  300  44 23   7.2   4.0
 19000 -21.9  -7.4  295  52 27   7.8   4.3 | -22.6  -8.7  300  43 22   7.2   4.0
 18500 -20.7  -5.3  295  51 26   7.9   4.4 | -21.5  -6.7  300  42 21   7.3   4.0
 18000 -19.6  -3.3  295  50 26   6.3   3.4 | -20.4  -4.7  300  40 21   6.6   3.6
 17500 -18.7  -1.7  295  49 25   6.3   3.5 | -19.4  -2.9  300  39 20   6.6   3.6
 17000 -17.7   0.1  300  48 25   6.3   3.5 | -18.4  -1.1  300  38 20   6.1   3.4
 16500 -16.7   1.9  300  47 24   6.3   3.5 | -17.6   0.3  300  37 19   5.8   3.2
 16000 -15.8   3.6  300  46 23   6.3   3.5 | -16.7   1.9  300  36 19   5.8   3.2
 15500 -14.4   6.1  300  43 22   6.2   3.4 | -15.4   4.3  300  35 18   5.9   3.2
 15000 -13.4   7.9  300  42 22   6.2   3.4 | -14.5   5.9  300  34 18   6.0   3.3
 14500 -12.5   9.5  300  41 21   6.2   3.4 | -13.6   7.5  300  34 17   6.2   3.4
 14000 -11.6  11.1  300  40 21   6.2   3.4 | -12.6   9.3  300  33 17   6.4   3.5
 13500 -10.7  12.7  300  39 20   6.2   3.4 | -11.7  10.9  300  33 17   6.7   3.7
 13000  -9.8  14.4  300  38 20   6.2   3.4 | -10.7  12.7  300  32 17   6.6   3.6
 12500  -8.8  16.2  300  38 19   6.6   3.6 |  -9.8  14.4  300  31 16   6.3   3.5
 12000  -7.9  17.8  300  37 19   6.5   3.6 |  -8.8  16.2  300  30 16   6.2   3.4
 11500  -7.0  19.4  305  37 19   5.7   3.1 |  -8.0  17.6  300  27 14   5.5   3.0
 11000  -6.1  21.0  305  36 18   5.7   3.1 |  -7.2  19.0  305  24 12   5.4   2.9
 10500  -5.4  22.3  305  34 18   5.1   2.8 |  -6.5  20.3  310  19 10   4.7   2.6
 10250  -5.0  23.0  305  34 17   4.8   2.6 |  -6.2  20.8  315  16  8   3.8   2.1
 10000  -4.6  23.7  305  33 17   6.2   3.4 |  -5.9  21.4  320  14  7   8.7   4.8
  9750  -4.1  24.6  310  31 16   6.6   3.6 |  -5.0  23.0  330  12  6  11.3   6.2
  9500  -3.7  25.3  310  30 15   5.6   3.1 |  -4.4  24.1  335  11  6   8.6   4.7
  9250  -3.3  26.1  310  28 15   5.7   3.2 |  -3.7  25.3  335  11  6   9.3   5.1
  9000  -2.9  26.8  315  27 14   6.2   3.4 |  -3.0  26.6  340  11  5   9.3   5.1
  8750  -2.4  27.7  315  25 13   6.9   3.8 |  -2.3  27.9  345  11  5   9.8   5.4
  8500  -1.9  28.6  315  23 12   6.7   3.7 |  -1.6  29.1  345  10  5  10.0   5.5
  8250  -1.4  29.5  320  21 11   7.0   3.8 |  -0.8  30.6  345  10  5  10.1   5.5
  8000  -0.9  30.4  325  19 10   8.8   4.8 |  -0.1  31.8  345  10  5  10.3   5.7
  7750  -0.2  31.6  325  18  9   8.4   4.6 |   0.7  33.3  345  10  5  10.0   5.5
  7500   0.3  32.5  330  16  8   6.8   3.7 |   1.4  34.5  350  10  5   9.5   5.2
  7250   0.8  33.4  330  15  8   8.0   4.4 |   2.2  36.0  350  10  5  10.3   5.7
  7000   1.5  34.7  335  14  7   9.3   5.1 |   3.0  37.4  350  10  5  11.2   6.1
  6750   2.1  35.8  340  12  6   7.8   4.3 |   3.8  38.8  350  10  5   9.8   5.4
  6500   2.6  36.7  350  11  5   7.1   3.9 |   4.5  40.1  350  10  5   9.5   5.2
  6250   3.2  37.8  355   9  5   9.7   5.3 |   5.2  41.4  350  10  5  10.9   6.0
  6000   4.0  39.2  360   8  4  10.9   6.0 |   6.1  43.0  350  10  5  10.9   6.0
  5750   4.7  40.5  360   7  4  10.0   5.5 |   6.9  44.4  350   9  5  11.6   6.4
  5500   5.5  41.9  005   7  4  12.4   6.8 |   8.0  46.4  350   9  5  18.6  10.2

           04/16/2014 at 1500 MDT          |       04/16/2014 at 1800 MDT
                                           |
K index... +9.3  LI... +3.4                | K index... +13.6  LI... +2.9
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 -55.7 -68.3  280  29 15   0.8   0.4 | -55.4 -67.7  295  27 14   0.4   0.2
 45000 -54.5 -66.1  295  34 18   0.8   0.5 | -54.8 -66.6  295  34 17   0.4   0.2
 40000 -54.8 -66.6  290  47 24  -0.3  -0.2 | -54.2 -65.6  295  43 22   0.3   0.2
 38000 -55.1 -67.2  285  53 28  -1.5  -0.8 | -54.4 -65.9  290  48 24  -1.9  -1.1
 36000 -56.1 -69.0  280  63 32  -1.6  -0.9 | -55.6 -68.1  280  55 28  -2.0  -1.1
 34000 -57.0 -70.6  275  73 38  -1.6  -0.9 | -56.8 -70.2  270  63 32  -2.2  -1.2
 32000 -53.0 -63.4  275  70 36   7.5   4.1 | -53.4 -64.1  270  63 33   6.6   3.6
 30000 -48.0 -54.4  275  65 34   7.6   4.2 | -48.8 -55.8  265  62 32   8.1   4.4
 29000 -45.8 -50.4  275  61 31   7.4   4.1 | -46.4 -51.5  270  57 29   8.1   4.5
 28000 -43.5 -46.3  280  57 29   7.4   4.1 | -44.0 -47.2  270  52 27   8.1   4.5
 27000 -41.3 -42.3  285  53 27   7.4   4.0 | -41.5 -42.7  275  48 24   8.1   4.5
 26000 -38.9 -38.0  285  50 26   8.3   4.5 | -39.1 -38.4  275  45 23   8.2   4.5
 25000 -36.4 -33.5  285  48 25   8.3   4.5 | -36.6 -33.9  275  43 22   8.2   4.5
 24000 -33.9 -29.0  290  46 24   8.3   4.6 | -34.2 -29.6  280  41 21   8.2   4.5
 23000 -31.5 -24.7  290  44 23   8.1   4.4 | -31.7 -25.1  280  38 20   8.2   4.5
 22000 -29.1 -20.4  285  41 21   8.1   4.4 | -29.3 -20.7  275  36 18   8.3   4.5
 21000 -26.7 -16.1  285  38 20   8.0   4.4 | -26.8 -16.2  275  33 17   8.0   4.4
 20000 -24.6 -12.3  285  35 18   6.8   3.8 | -24.9 -12.8  275  33 17   6.2   3.4
 19500 -23.5 -10.3  285  34 18   6.9   3.8 | -23.9 -11.0  275  32 17   6.2   3.4
 19000 -22.5  -8.5  280  33 17   6.9   3.8 | -23.0  -9.4  275  32 17   6.3   3.4
 18500 -21.5  -6.7  280  32 16   7.0   3.8 | -22.1  -7.8  275  32 17   6.3   3.4
 18000 -20.6  -5.1  280  32 16   5.7   3.1 | -21.1  -6.0  275  32 16   6.5   3.6
 17500 -19.7  -3.5  280  32 16   5.8   3.2 | -20.2  -4.4  275  32 16   6.5   3.6
 17000 -18.8  -1.8  280  32 17   5.6   3.1 | -19.2  -2.6  275  32 16   5.9   3.3
 16500 -18.0  -0.4  280  33 17   5.5   3.0 | -18.4  -1.1  275  32 16   5.8   3.2
 16000 -17.2   1.0  280  33 17   5.7   3.1 | -17.5   0.5  275  32 17   6.3   3.5
 15500 -15.8   3.6  280  33 17   6.5   3.6 | -15.9   3.4  275  31 16   7.6   4.1
 15000 -14.8   5.4  280  33 17   6.7   3.7 | -14.8   5.4  275  30 15   7.5   4.1
 14500 -13.8   7.2  280  31 16   6.8   3.7 | -13.7   7.3  275  28 14   7.4   4.1
 14000 -12.8   9.0  280  29 15   6.8   3.7 | -12.6   9.3  280  26 13   6.9   3.8
 13500 -11.8  10.8  285  26 13   6.7   3.7 | -11.6  11.1  280  22 11   6.3   3.4
 13000 -10.8  12.6  285  23 12   6.4   3.5 | -10.7  12.7  280  19 10   5.7   3.1
 12500 -10.0  14.0  290  18  9   5.4   3.0 | -10.0  14.0  290  13  7   4.7   2.6
 12000  -9.2  15.4  300  13  7   5.8   3.2 |  -9.3  15.3  310   8  4   5.3   2.9
 11500  -8.3  17.1  320  10  5   6.9   3.8 |  -8.4  16.9  345   8  4   6.4   3.5
 11000  -7.3  18.9  350   9  4   6.9   3.8 |  -7.5  18.5  010  10  5   6.9   3.8
 10500  -6.3  20.7  360   9  5   6.7   3.7 |  -6.4  20.5  015  11  5   6.8   3.7
 10250  -5.7  21.7  005   9  5   8.5   4.6 |  -5.8  21.6  015  11  6  10.9   6.0
 10000  -5.0  23.0  010  10  5  11.9   6.5 |  -4.8  23.4  015  11  6  12.2   6.7
  9750  -4.1  24.6  010  10  5  11.0   6.0 |  -4.1  24.6  015  11  6   9.0   5.0
  9500  -3.3  26.1  010  10  5   9.6   5.3 |  -3.4  25.9  015  11  6  10.0   5.5
  9250  -2.6  27.3  010  10  5   9.6   5.3 |  -2.7  27.1  015  12  6   9.2   5.1
  9000  -1.9  28.6  010  10  5   9.0   4.9 |  -2.0  28.4  015  12  6   8.9   4.9
  8750  -1.2  29.8  010  10  5   9.8   5.4 |  -1.3  29.7  015  12  6   9.9   5.4
  8500  -0.5  31.1  010  10  5  10.3   5.6 |  -0.5  31.1  015  12  6  10.5   5.8
  8250   0.3  32.5  010  10  5  10.4   5.7 |   0.3  32.5  015  12  6  10.1   5.5
  8000   1.1  34.0  010  10  5  10.7   5.9 |   1.0  33.8  015  12  6   9.7   5.3
  7750   1.9  35.4  010  10  5   9.7   5.3 |   1.7  35.1  015  12  6   9.8   5.4
  7500   2.6  36.7  010  10  5   9.0   4.9 |   2.5  36.5  015  12  6   9.9   5.4
  7250   3.3  37.9  010  10  5  10.3   5.7 |   3.2  37.8  015  12  6  10.3   5.6
  7000   4.1  39.4  010  10  5  11.4   6.2 |   4.0  39.2  015  12  6  10.7   5.9
  6750   4.9  40.8  010  10  5  10.2   5.6 |   4.8  40.6  015  12  6   9.7   5.3
  6500   5.6  42.1  010  10  5   9.9   5.4 |   5.5  41.9  015  12  6   9.6   5.3
  6250   6.4  43.5  010  10  5  10.7   5.9 |   6.2  43.2  015  12  6  10.5   5.8
  6000   7.2  45.0  010  10  5  10.3   5.7 |   7.0  44.6  015  12  6  10.3   5.6
  5750   8.0  46.4  010  10  5  11.8   6.5 |   7.8  46.0  015  12  6  10.4   5.7
  5500   9.1  48.4  010  10  5  19.9  10.9 |   8.6  47.5  015  11  6  13.1   7.2
________________________________________________________________________________

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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