Soaring Guidance
Issued by NWS Denver/Boulder, CO

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605
UXUS97 KBOU 171220
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0619 MDT Tuesday, April 17, 2018

This forecast is for Tuesday, April 17, 2018:

If the trigger temperature of 65.1 F/18.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 373 ft/min (1.9 m/s)
   Maximum height of thermals.................. 10460 ft MSL (5175 ft AGL)

Forecast maximum temperature................... 68.0 F/20.5 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 8406 ft MSL (3121 ft AGL)
Thermal soaring outlook for Wednesday 04/18.... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 14389 ft MSL (9104 ft AGL)
Wave soaring outlook for Wednesday 04/18....... Poor

Remarks...

Sunrise/Sunset.................... 06:18:31 / 19:39:27 MDT
Total possible sunshine........... 13 hr 20 min 56 sec (800 min 56 sec)
Altitude of sun at 12:58:59 MDT... 60.88 degrees

Upper air data from rawinsonde observation taken on 04/17/2018 at 0600 MDT

Freezing level.................. 13907 ft MSL (8622 ft AGL)
Convective condensation level... 21137 ft MSL (15852 ft AGL)
Lifted condensation level....... 17794 ft MSL (12508 ft AGL)
Lifted index.................... +5.4
K index......................... -27.3

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  -59.5 -75.1   235   87   45 -12.9  -7.1   99.0 210.3    45.4      M    M
 45000  -58.3 -72.9   240   86   44  -6.6  -3.6   75.2 167.4    34.1      M    M
 40000  -59.0 -74.2   240   89   46  -8.2  -4.5   51.4 124.4    20.7      M    M
 38000  -59.4 -74.9   235   90   46   7.0   3.9   42.0 107.7    15.0      M    M
 36000  -55.6 -68.1   235   83   43   6.3   3.5   39.0 102.1    13.2      M    M
 34000  -51.8 -61.2   235   76   39   6.0   3.3   36.1  97.0    11.5      M    M
 32000  -47.6 -53.7   240   70   36   8.6   4.7   33.8  92.9    10.2      M    M
 30000  -41.8 -43.2   245   66   34   8.7   4.7   32.9  91.3     9.8      M    M
 29000  -39.2 -38.6   245   63   33   8.7   4.7   32.3  90.1     9.4      M    M
 28000  -36.6 -33.9   240   61   32   8.7   4.7   31.8  89.2     9.1      M    M
 27000  -34.0 -29.2   240   59   30   8.7   4.7   31.4  88.5     8.9      M    M
 26000  -31.4 -24.5   235   57   29   8.7   4.7   31.1  88.0     8.8      M    M
 25000  -28.8 -19.8   235   55   28   8.7   4.7   31.0  87.7     8.8      M    M
 24000  -26.2 -15.2   230   53   27   8.7   4.8   30.4  86.8     8.5      M    M
 23000  -23.6 -10.5   230   51   26   8.7   4.8   29.9  85.8     8.2      M    M
 22000  -21.0  -5.8   230   49   25   8.7   4.8   29.5  85.1     7.9      M    M
 21000  -18.4  -1.1   230   46   24   8.7   4.8   29.2  84.6     7.8      M    M
 20000  -15.8   3.6   230   44   23   8.7   4.8   29.0  84.2     7.7      M    M
 19500  -14.5   5.9   230   44   23   8.7   4.8   28.8  83.8     7.5      M    M
 19000  -13.2   8.2   225   44   23   8.7   4.8   28.6  83.4     7.4      M    M
 18500  -11.9  10.6   225   44   23   9.2   5.0   28.4  83.1     7.2      M    M
 18000  -10.5  13.1   225   44   23   9.6   5.3   28.3  83.0     7.2      M    M
 17500   -9.0  15.8   225   44   22   9.7   5.3   28.3  82.9     7.2      M    M
 17000   -7.6  18.3   220   43   22   9.7   5.3   28.3  82.9     7.3      M    M
 16500   -6.2  20.8   220   43   22   8.2   4.5   28.3  82.9     7.3      M    M
 16000   -5.0  23.0   220   43   22   7.5   4.1   27.9  82.2     7.0      M    M
 15500   -3.9  25.0   220   43   22   7.5   4.1   27.5  81.6     6.7      M    M
 15000   -2.2  28.0   225   44   23   7.5   4.1   27.0  80.6     6.3      M    M
 14500   -1.1  30.0   230   45   23   7.5   4.1   26.6  79.9     6.0      M    M
 14000    0.0  32.0   230   46   24   7.5   4.1   26.3  79.3     5.7      M    M
 13500    1.1  34.0   230   49   25   7.5   4.1   25.8  78.5     5.3      M    M
 13000    2.3  36.1   235   51   26   7.5   4.1   25.5  77.8     5.0      M    M
 12500    3.4  38.1   235   53   27   7.5   4.1   25.1  77.2     4.7      M    M
 12000    4.5  40.1   235   55   29   7.4   4.1   24.7  76.5     4.4      M    M
 11500    5.6  42.1   235   58   30   6.2   3.4   24.3  75.8     4.1      M    M
 11000    5.3  41.5   235   61   31  -6.9  -3.8   22.5  72.5     2.3      M    M
 10500    4.5  40.1   235   59   30   1.7   0.9   20.2  68.3    -0.0    373  1.9
 10250    5.0  41.0   230   58   30   8.2   4.5   20.0  67.9    -0.3    351  1.8
 10000    5.5  41.9   230   57   29   6.3   3.5   19.7  67.5    -0.5    328  1.7
  9750    5.9  42.6   230   56   29   5.2   2.9   19.4  67.0    -0.8    308  1.6
  9500    6.2  43.2   230   54   28   4.1   2.2   19.0  66.2    -1.2    291  1.5
  9250    6.5  43.7   230   52   27   4.4   2.4   18.6  65.4    -1.7    274  1.4
  9000    6.8  44.2   230   51   26   4.4   2.4   18.2  64.7    -2.1    258  1.3
  8750    7.1  44.8   230   48   25   4.1   2.3   17.7  63.9    -2.5    241  1.2
  8500    7.5  45.5   230   46   24   5.3   2.9   17.3  63.2    -2.9    224  1.1
  8250    8.0  46.4   230   43   22   8.4   4.6   17.1  62.8    -3.2    202  1.0
  8000    8.6  47.5   230   41   21   9.4   5.2   17.1  62.7    -3.2    174  0.9
  7750    9.3  48.7   230   39   20   9.1   5.0   17.0  62.6    -3.3    146  0.7
  7500   10.0  50.0   230   37   19   9.2   5.1   17.0  62.6    -3.3    118  0.6
  7250   10.7  51.3   230   36   18   9.2   5.0   16.9  62.5    -3.4     90  0.5
  7000   11.4  52.5   230   34   18   9.2   5.0   16.9  62.4    -3.4     62  0.3
  6750   12.0  53.6   230   32   16   9.2   5.0   16.9  62.3    -3.5     35  0.2
  6500   12.7  54.9   230   30   15   9.2   5.0   16.8  62.3    -3.5      7  0.0
  6250   13.4  56.1   230   27   14   9.3   5.1   16.8  62.2    -3.6      M    M
  6000   14.1  57.4   230   25   13   8.8   4.8   16.7  62.1    -3.7      M    M
  5750   14.8  58.6   230   21   11  10.8   5.9   16.7  62.0    -3.7      M    M
  5500   14.7  58.5   225   16    8 -25.5 -14.0   15.9  60.6    -4.5      M    M

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

           04/17/2018 at 0900 MDT          |       04/17/2018 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +8.2        | CAPE...    +0.3    LI...       +5.4
CINH...    -0.0    K Index... -21.4        | CINH...    -0.0    K Index...  +1.0
                                           |
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 -59.0 -74.2  240  34 18  -1.0  -0.6 | -57.3 -71.1  240  34 18  -0.6  -0.3
 45000 -60.5 -76.9  230  38 19   1.0   0.6 | -58.2 -72.8  230  43 22   0.7   0.4
 40000 -57.5 -71.5  230  37 19   2.0   1.1 | -55.2 -67.4  225  40 21   2.0   1.1
 38000 -55.6 -68.1  225  38 19   4.4   2.4 | -53.3 -63.9  225  40 20   4.4   2.4
 36000 -52.9 -63.2  225  39 20   4.4   2.4 | -50.3 -58.5  225  41 21   4.4   2.4
 34000 -49.5 -57.1  225  39 20   7.0   3.8 | -47.6 -53.7  225  42 21   5.8   3.2
 32000 -45.3 -49.5  225  39 20   7.1   3.9 | -44.1 -47.4  225  44 23   5.7   3.1
 30000 -40.9 -41.6  225  39 20   8.0   4.4 | -40.6 -41.1  225  46 24   7.0   3.9
 29000 -38.5 -37.3  225  38 20   8.0   4.4 | -38.5 -37.3  225  47 24   6.9   3.8
 28000 -36.1 -33.0  225  38 20   8.0   4.4 | -36.4 -33.5  230  48 25   6.9   3.8
 27000 -33.7 -28.7  225  38 19   8.1   4.5 | -34.3 -29.7  230  48 25   6.9   3.8
 26000 -31.2 -24.2  225  37 19   8.3   4.6 | -32.1 -25.8  225  48 25   7.5   4.1
 25000 -28.7 -19.7  225  37 19   8.3   4.6 | -29.9 -21.8  225  48 25   7.5   4.1
 24000 -26.2 -15.2  225  37 19   8.3   4.6 | -27.7 -17.9  225  48 25   7.5   4.1
 23000 -23.8 -10.8  225  36 19   8.1   4.5 | -25.4 -13.7  225  48 24   7.5   4.1
 22000 -21.3  -6.3  225  36 19   8.1   4.5 | -23.2  -9.8  225  47 24   7.5   4.1
 21000 -18.9  -2.0  225  36 19   8.0   4.4 | -20.9  -5.6  230  47 24   7.8   4.3
 20000 -16.5   2.3  225  36 19   7.8   4.3 | -19.1  -2.4  230  45 23   5.7   3.1
 19500 -14.8   5.4  225  36 19   7.8   4.3 | -17.8  -0.0  225  42 22   5.7   3.1
 19000 -13.6   7.5  225  36 19   7.8   4.3 | -17.0   1.4  225  41 21   5.7   3.1
 18500 -12.5   9.5  225  36 19   7.4   4.0 | -16.1   3.0  225  39 20   5.4   3.0
 18000 -11.4  11.5  225  36 19   7.1   3.9 | -15.5   4.1  225  38 19   3.8   2.1
 17500 -10.4  13.3  225  36 19   7.1   3.9 | -14.9   5.2  230  37 19   3.9   2.1
 17000  -9.4  15.1  225  36 19   6.2   3.4 | -14.4   6.1  230  36 18   3.6   2.0
 16500  -8.4  16.9  225  36 19   6.3   3.5 | -13.8   7.2  230  34 17   3.6   2.0
 16000  -7.5  18.5  225  36 19   5.7   3.1 | -13.3   8.1  230  32 16   4.0   2.2
 15500  -6.7  19.9  225  36 18   5.4   3.0 | -12.6   9.3  230  29 15   4.6   2.5
 15000  -5.9  21.4  225  36 18   5.2   2.8 | -12.0  10.4  235  27 14   5.0   2.8
 14500  -5.2  22.6  225  34 18   4.5   2.5 | -10.9  12.4  235  25 13   8.4   4.6
 14000  -4.5  23.9  225  32 16   4.6   2.5 |  -9.7  14.5  235  23 12   8.1   4.4
 13500  -3.8  25.2  225  30 16   4.9   2.7 |  -8.4  16.9  235  22 11   9.7   5.3
 13000  -3.1  26.4  225  29 15   4.8   2.6 |  -7.0  19.4  235  21 11   9.5   5.2
 12500  -2.3  27.9  230  27 14   6.2   3.4 |  -5.5  22.1  235  21 11   9.6   5.3
 12000  -1.4  29.5  230  26 14   6.0   3.3 |  -4.1  24.6  235  20 10   9.6   5.3
 11500  -0.4  31.3  230  26 13   7.6   4.2 |  -2.6  27.3  235  20 10   9.8   5.4
 11000   0.7  33.3  230  25 13   7.7   4.2 |  -1.2  29.8  235  19 10   9.8   5.4
 10500   1.8  35.2  230  25 13   6.3   3.5 |   0.2  32.4  235  19 10   8.7   4.8
 10250   2.3  36.1  230  25 13   7.3   4.0 |   0.9  33.6  235  19 10   9.5   5.2
 10000   2.9  37.2  230  25 13   9.0   4.9 |   1.7  35.1  235  19 10  10.9   6.0
  9750   3.6  38.5  230  24 12   8.8   4.8 |   2.5  36.5  235  18  9  11.1   6.1
  9500   4.2  39.6  230  24 12   8.3   4.6 |   3.3  37.9  235  18  9  10.9   6.0
  9250   4.8  40.6  230  23 12   8.7   4.8 |   4.2  39.6  235  18  9  11.5   6.3
  9000   5.4  41.7  230  23 12   6.3   3.5 |   5.0  41.0  235  18  9   8.1   4.4
  8750   5.9  42.6  230  23 12   7.1   3.9 |   5.5  41.9  235  18  9   7.9   4.3
  8500   6.5  43.7  230  22 11   9.7   5.3 |   6.2  43.2  235  18  9  10.7   5.9
  8250   7.2  45.0  230  21 11   9.1   5.0 |   7.0  44.6  235  17  9  10.0   5.5
  8000   7.9  46.2  225  21 11   8.7   4.8 |   7.7  45.9  235  17  9   9.9   5.4
  7750   8.5  47.3  225  20 10   8.8   4.8 |   8.5  47.3  235  17  9   9.8   5.4
  7500   9.2  48.6  225  19 10   9.6   5.2 |   9.2  48.6  235  17  9  10.0   5.5
  7250   9.9  49.8  225  18  9   9.5   5.2 |  10.0  50.0  235  16  8  10.1   5.5
  7000  10.6  51.1  225  18  9   9.0   5.0 |  10.7  51.3  235  16  8   9.6   5.3
  6750  11.3  52.3  225  17  9   9.4   5.2 |  11.4  52.5  235  16  8  10.0   5.5
  6500  12.0  53.6  225  16  8  10.2   5.6 |  12.2  54.0  235  16  8  10.7   5.9
  6250  12.8  55.0  225  15  8  10.0   5.5 |  13.0  55.4  235  15  8  10.7   5.9
  6000  13.6  56.5  225  14  7  10.9   6.0 |  13.8  56.8  240  15  8  10.8   5.9
  5750  14.4  57.9  225  13  7  13.1   7.2 |  14.8  58.6  235  14  7  17.2   9.4
  5500  15.5  59.9  225  11  6  14.9   8.2 |  16.5  61.7  235  12  6  28.0  15.4

           04/17/2018 at 1500 MDT          |       04/17/2018 at 1800 MDT
                                           |
CAPE...   +24.8    LI...       +2.0        | CAPE...    +1.0    LI...       +1.3
CINH...    -0.6    K Index...  +7.6        | CINH...    -1.4    K Index...  +3.6
                                           |
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 -55.2 -67.4  245  33 17  -0.0  -0.0 | -54.1 -65.4  240  31 16   0.8   0.5
 45000 -55.2 -67.4  235  44 23   0.3   0.2 | -52.8 -63.0  245  41 21   0.8   0.4
 40000 -51.7 -61.1  230  41 21   2.3   1.2 | -50.0 -58.0  250  41 21   1.8   1.0
 38000 -49.9 -57.8  230  41 21   3.9   2.1 | -48.6 -55.5  250  41 21   3.1   1.7
 36000 -47.6 -53.7  235  42 22   3.9   2.1 | -46.8 -52.2  255  41 21   3.1   1.7
 34000 -45.3 -49.5  235  43 22   4.0   2.2 | -44.9 -48.8  255  42 22   3.2   1.7
 32000 -42.8 -45.0  235  47 24   4.2   2.3 | -42.8 -45.0  255  41 21   3.6   2.0
 30000 -40.3 -40.5  235  50 26   4.6   2.5 | -40.4 -40.7  255  40 21   3.2   1.8
 29000 -38.3 -36.9  235  50 26   5.3   2.9 | -39.6 -39.3  255  38 20   2.8   1.6
 28000 -36.7 -34.1  235  50 26   5.3   2.9 | -38.7 -37.7  255  37 19   2.8   1.6
 27000 -35.1 -31.2  235  51 26   5.3   2.9 | -37.8 -36.0  260  35 18   2.8   1.5
 26000 -33.5 -28.3  235  49 25   5.4   3.0 | -37.2 -35.0  260  32 17   1.6   0.9
 25000 -31.9 -25.4  235  47 24   5.4   3.0 | -36.7 -34.1  260  28 15   1.5   0.8
 24000 -30.3 -22.5  235  45 23   5.4   2.9 | -36.3 -33.3  265  24 12   1.6   0.9
 23000 -28.9 -20.0  235  42 22   3.8   2.1 | -35.3 -31.5  265  21 11   6.3   3.5
 22000 -27.8 -18.0  235  37 19   3.8   2.1 | -33.5 -28.3  270  18  9   6.1   3.4
 21000 -26.7 -16.1  235  32 16   3.7   2.0 | -31.6 -24.9  270  16  8   6.1   3.3
 20000 -25.2 -13.4  235  28 14   5.7   3.1 | -29.5 -21.1  275  15  8   7.9   4.3
 19500 -24.4 -11.9  235  27 14   5.7   3.1 | -28.3 -18.9  275  15  8   7.9   4.3
 19000 -23.5 -10.3  240  25 13   5.7   3.1 | -27.1 -16.8  280  15  8   7.9   4.3
 18500 -22.7  -8.9  240  23 12   5.7   3.1 | -25.9 -14.6  280  15  8   7.9   4.3
 18000 -21.9  -7.4  240  22 11   4.2   2.3 | -24.8 -12.6  280  15  8   8.1   4.5
 17500 -21.4  -6.5  245  21 11   3.6   2.0 | -23.5 -10.3  285  15  8   8.2   4.5
 17000 -20.9  -5.6  255  20 10   4.2   2.3 | -22.3  -8.1  285  15  8   8.2   4.5
 16500 -19.9  -3.8  255  19 10   7.3   4.0 | -20.5  -4.9  290  16  8   8.3   4.5
 16000 -18.9  -2.0  255  18  9   7.0   3.9 | -19.2  -2.6  290  16  8   8.3   4.6
 15500 -17.2   1.0  260  17  9   8.2   4.5 | -18.0  -0.4  295  16  8   8.4   4.6
 15000 -15.9   3.4  260  16  8   8.3   4.5 | -16.7   1.9  295  17  9   8.4   4.6
 14500 -14.7   5.5  265  16  8   8.5   4.7 | -15.5   4.1  300  17  9   8.3   4.5
 14000 -13.4   7.9  265  16  8   8.5   4.6 | -14.3   6.3  300  18  9   8.3   4.5
 13500 -12.1  10.2  270  16  8   9.1   5.0 | -13.0   8.6  300  19 10   8.2   4.5
 13000 -10.8  12.6  270  16  8   9.1   5.0 | -11.8  10.8  305  19 10   8.3   4.5
 12500  -9.4  15.1  270  16  8   9.0   4.9 | -10.7  12.7  305  20 10   7.4   4.1
 12000  -8.1  17.4  275  16  8   9.0   4.9 |  -9.6  14.7  305  21 11   7.5   4.1
 11500  -6.7  19.9  275  16  8   9.4   5.1 |  -8.4  16.9  305  21 11   7.6   4.2
 11000  -5.3  22.5  275  16  8   9.5   5.2 |  -7.3  18.9  305  22 11   7.7   4.2
 10500  -4.1  24.6  275  16  8   7.3   4.0 |  -6.2  20.8  300  22 11   8.0   4.4
 10250  -3.5  25.7  275  16  8   8.1   4.4 |  -5.6  21.9  300  21 11   8.0   4.4
 10000  -2.8  27.0  275  16  8  12.2   6.7 |  -5.0  23.0  300  21 11   8.1   4.5
  9750  -1.8  28.8  275  16  8  11.6   6.4 |  -4.4  24.1  300  21 11   8.5   4.6
  9500  -1.1  30.0  275  16  8   8.9   4.9 |  -3.8  25.2  300  21 11   8.7   4.8
  9250  -0.4  31.3  275  16  8   9.6   5.3 |  -3.1  26.4  300  20 10   8.2   4.5
  9000   0.3  32.5  280  16  8   9.7   5.3 |  -2.5  27.5  300  20 10  10.0   5.5
  8750   1.0  33.8  275  16  8  10.2   5.6 |  -1.7  28.9  300  20 10  10.4   5.7
  8500   1.8  35.2  275  16  8   9.9   5.5 |  -1.0  30.2  295  19 10   8.9   4.9
  8250   2.5  36.5  275  16  8  10.7   5.9 |  -0.3  31.5  295  19 10   9.3   5.1
  8000   3.3  37.9  275  15  8   8.0   4.4 |   0.4  32.7  295  19 10   9.1   5.0
  7750   3.8  38.8  280  15  8   8.5   4.7 |   1.1  34.0  295  19 10   9.6   5.3
  7500   4.6  40.3  280  15  8  11.4   6.3 |   1.8  35.2  295  18  9  10.1   5.5
  7250   5.4  41.7  280  15  8  11.1   6.1 |   2.6  36.7  295  18  9   9.9   5.5
  7000   6.2  43.2  280  15  8   8.1   4.4 |   3.3  37.9  295  18  9   9.9   5.4
  6750   6.7  44.1  280  15  8   9.0   4.9 |   4.0  39.2  295  18  9  10.1   5.5
  6500   7.6  45.7  280  15  8  12.9   7.1 |   4.8  40.6  295  17  9  10.2   5.6
  6250   8.5  47.3  280  14  7  11.4   6.2 |   5.6  42.1  295  16  8  10.7   5.9
  6000   9.3  48.7  280  14  7  10.8   5.9 |   6.4  43.5  295  16  8  11.7   6.4
  5750  10.1  50.2  280  14  7  10.0   5.5 |   7.3  45.1  295  15  8  10.0   5.5
  5500  11.1  52.0  280  12  6  18.6  10.2 |   8.0  46.4  295  14  7  12.0   6.6
________________________________________________________________________________

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.

CINH (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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