Soaring Guidance
Issued by NWS Denver/Boulder, CO

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899
UXUS97 KBOU 231229
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0629 MDT Thursday, March 23, 2017

This forecast is for Thursday, March 23, 2017:

If the trigger temperature of 69.2 F/20.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 827 ft/min (4.2 m/s)
   Maximum height of thermals.................. 14354 ft MSL (9069 ft AGL)

Forecast maximum temperature................... 73.0 F/23.2 C
Time of trigger temperature.................... 1145 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................. 7140 ft MSL (1855 ft AGL)
Thermal soaring outlook for Friday 03/24....... Poor

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....................... 23505 ft MSL (18220 ft AGL)
Wave soaring outlook for Friday 03/24.......... Poor

Remarks... None

Sunrise/Sunset.................... 06:57:12 / 19:14:35 MDT
Total possible sunshine........... 12 hr 17 min 24 sec (737 min 24 sec)
Altitude of sun at 13:05:53 MDT... 51.52 degrees

Upper air data from rawinsonde observation taken on 03/23/2017 at 0600 MDT

Freezing level.................. 12612 ft MSL (7327 ft AGL)
Convective condensation level... 17773 ft MSL (12488 ft AGL)
Lifted condensation level....... 17361 ft MSL (12076 ft AGL)
Lifted index.................... +0.3
K index......................... +7.6

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -63.0 -81.4   250   48   25   6.2   3.4   92.7 198.8    40.2      M    M
 45000  -55.9 -68.6   230   77   39   3.6   2.0   78.9 174.0    34.6      M    M
 40000  -55.0 -67.0   220   51   26  -2.8  -1.5   57.4 135.3    22.9      M    M
 38000  -56.0 -68.8   240   72   37   4.7   2.6   47.2 117.0    16.6      M    M
 36000  -53.2 -63.8   225   64   33   4.7   2.6   42.8 109.0    13.9      M    M
 34000  -48.8 -55.8   230   76   39   7.9   4.3   40.7 105.2    12.8      M    M
 32000  -44.1 -47.4   225   80   41   7.9   4.3   39.1 102.4    12.0      M    M
 30000  -38.8 -37.8   220   74   38   5.1   2.8   37.5  99.5    11.1      M    M
 29000  -38.3 -36.9   220   67   34   1.4   0.8   34.2  93.5     8.7      M    M
 28000  -37.7 -35.9   220   60   31   5.2   2.8   31.2  88.2     6.5      M    M
 27000  -35.9 -32.6   220   65   33   6.0   3.3   29.7  85.5     5.4      M    M
 26000  -33.7 -28.7   215   69   36   9.9   5.4   28.8  83.8     4.8      M    M
 25000  -30.8 -23.4   215   74   38   9.6   5.3   28.8  83.8     4.8      M    M
 24000  -27.9 -18.2   215   75   39   8.2   4.5   28.7  83.7     4.8      M    M
 23000  -26.0 -14.8   215   77   40   7.9   4.3   27.6  81.7     3.9      M    M
 22000  -23.3  -9.9   220   70   36   8.7   4.8   27.1  80.9     3.6      M    M
 21000  -20.7  -5.3   220   63   32   8.2   4.5   26.8  80.3     3.4      M    M
 20000  -18.6  -1.5   225   56   29   7.0   3.9   25.9  78.7     2.6      M    M
 19500  -17.5   0.5   225   52   27   7.1   3.9   25.4  77.7     2.2      M    M
 19000  -16.5   2.3   225   48   25   7.1   3.9   24.9  76.9     1.8      M    M
 18500  -15.4   4.3   225   44   23   8.0   4.4   24.5  76.1     1.4      M    M
 18000  -14.1   6.6   225   41   21   8.7   4.8   24.3  75.8     1.2      M    M
 17500  -12.9   8.8   225   41   21   8.8   4.8   24.2  75.5     1.1      M    M
 17000  -11.6  11.1   225   41   21   8.5   4.7   24.0  75.2     0.9      M    M
 16500  -10.3  13.5   225   41   21   8.5   4.7   23.8  74.9     0.8      M    M
 16000   -9.0  15.8   225   41   21   8.5   4.7   23.7  74.6     0.6      M    M
 15500   -7.1  19.2   225   41   21   8.5   4.7   23.4  74.1     0.3      M    M
 15000   -5.9  21.4   225   40   21   8.5   4.7   23.2  73.8     0.2      M    M
 14500   -4.6  23.7   225   40   21   8.5   4.7   23.0  73.5     0.0      M    M
 14000   -3.3  26.1   225   40   21   8.5   4.7   22.9  73.2    -0.1    778  4.0
 13500   -2.1  28.2   225   41   21   8.5   4.7   22.6  72.8    -0.4    726  3.7
 13000   -0.8  30.6   220   42   21   8.6   4.7   22.4  72.4    -0.6    673  3.4
 12500    0.5  32.9   220   42   22   8.6   4.7   22.2  72.0    -0.8    620  3.1
 12000    1.7  35.1   220   43   22   8.6   4.7   22.1  71.7    -1.0    567  2.9
 11500    3.0  37.4   215   45   23   8.6   4.7   21.8  71.3    -1.2    514  2.6
 11000    4.3  39.7   215   46   24   8.6   4.7   21.6  70.9    -1.4    461  2.3
 10500    5.6  42.1   215   43   22   8.6   4.7   21.4  70.5    -1.7    409  2.1
 10250    6.2  43.2   220   42   22   8.5   4.7   21.3  70.3    -1.8    382  1.9
 10000    6.8  44.2   220   41   21   8.8   4.8   21.2  70.1    -1.9    356  1.8
  9750    7.5  45.5   220   40   21   9.3   5.1   21.1  70.0    -2.0    328  1.7
  9500    8.2  46.8   220   40   20   9.4   5.1   21.1  69.9    -2.0    300  1.5
  9250    8.9  48.0   225   39   20   9.3   5.1   21.1  69.9    -2.0    272  1.4
  9000    9.6  49.3   225   38   20   9.4   5.1   21.0  69.9    -2.1    243  1.2
  8750   10.3  50.5   225   37   19   9.3   5.1   21.0  69.8    -2.1    215  1.1
  8500   11.0  51.8   225   36   18   9.4   5.1   21.0  69.7    -2.2    187  1.0
  8250   11.7  53.1   230   35   18   9.3   5.1   20.9  69.7    -2.2    159  0.8
  8000   12.4  54.3   230   34   17   9.6   5.3   20.9  69.6    -2.3    131  0.7
  7750   13.0  55.4   230   33   17   7.7   4.2   20.8  69.5    -2.3    103  0.5
  7500   13.5  56.3   230   32   17   6.0   3.3   20.6  69.1    -2.6     82  0.4
  7250   14.0  57.2   235   32   16   6.5   3.5   20.3  68.6    -2.9     60  0.3
  7000   14.4  57.9   235   31   16   6.3   3.5   20.1  68.1    -3.1     39  0.2
  6750   14.9  58.8   235   30   15   6.4   3.5   19.8  67.7    -3.4     18  0.1
  6500   15.3  59.5   235   29   15   6.2   3.4   19.5  67.2    -3.7      M    M
  6250   15.8  60.4   235   28   14   7.0   3.9   19.3  66.7    -4.0      M    M
  6000   16.0  60.8   235   27   14  -7.6  -4.2   18.7  65.7    -4.6      M    M
  5750   14.6  58.3   230   19   10 -21.7 -11.9   16.7  62.0    -6.7      M    M
  5500   13.2  55.8   215   10    5 -10.8  -5.9   14.6  58.3    -8.8     32  0.2

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

           03/23/2017 at 0900 MDT          |       03/23/2017 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +3.2        | CAPE...     0.0    LI...       +3.3
CINH...     0.0    K Index... -18.7        | CINH...     0.0    K Index... -15.3
                                           |
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 -59.8 -75.6  235  30 15   3.6   2.0 | -58.0 -72.4  235  24 12   3.4   1.9
 45000 -54.3 -65.7  235  34 18   0.7   0.4 | -52.9 -63.2  235  31 16   0.4   0.2
 40000 -52.9 -63.2  225  29 15   0.9   0.5 | -51.8 -61.2  220  29 15   0.7   0.4
 38000 -51.9 -61.4  220  32 17   2.3   1.2 | -51.2 -60.2  215  32 17   1.3   0.7
 36000 -50.5 -58.9  225  40 20   2.3   1.2 | -50.4 -58.7  215  38 20   1.3   0.7
 34000 -48.9 -56.0  225  46 24   5.7   3.1 | -49.4 -56.9  220  44 23   4.9   2.7
 32000 -45.2 -49.4  220  47 24   5.5   3.0 | -46.1 -51.0  210  47 24   4.9   2.7
 30000 -41.7 -43.1  215  46 24   6.5   3.6 | -42.9 -45.2  210  48 25   6.9   3.8
 29000 -39.8 -39.6  215  45 23   6.5   3.6 | -40.8 -41.4  205  47 24   6.9   3.8
 28000 -37.8 -36.0  210  44 23   6.5   3.6 | -38.8 -37.8  205  46 24   6.9   3.8
 27000 -35.9 -32.6  210  43 22   7.4   4.1 | -36.7 -34.1  200  46 23   7.3   4.0
 26000 -33.4 -28.1  210  43 22   8.2   4.5 | -34.3 -29.7  200  44 23   8.3   4.6
 25000 -31.0 -23.8  205  42 22   8.2   4.5 | -31.8 -25.2  200  43 22   8.3   4.6
 24000 -28.5 -19.3  205  41 21   8.1   4.5 | -29.3 -20.7  200  41 21   8.3   4.6
 23000 -26.2 -15.2  205  39 20   7.5   4.1 | -27.0 -16.6  200  39 20   7.5   4.1
 22000 -24.0 -11.2  210  37 19   7.5   4.1 | -24.8 -12.6  200  38 19   7.5   4.1
 21000 -21.8  -7.2  210  35 18   7.6   4.2 | -22.5  -8.5  205  36 18   7.8   4.3
 20000 -19.4  -2.9  210  32 16   7.8   4.3 | -20.0  -4.0  205  34 18   8.3   4.6
 19500 -18.3  -0.9  210  30 16   7.8   4.3 | -18.8  -1.8  205  33 17   8.3   4.6
 19000 -17.1   1.2  210  29 15   7.8   4.3 | -17.5   0.5  210  32 17   8.3   4.6
 18500 -15.3   4.5  210  27 14   7.9   4.3 | -15.7   3.7  210  31 16   8.0   4.4
 18000 -14.1   6.6  210  26 14   7.9   4.4 | -14.5   5.9  210  30 16   7.9   4.3
 17500 -13.0   8.6  215  26 13   8.1   4.5 | -13.3   8.1  210  29 15   7.8   4.3
 17000 -11.7  10.9  215  25 13   8.8   4.8 | -12.2  10.0  215  29 15   7.4   4.0
 16500 -10.4  13.3  215  24 12   8.7   4.8 | -11.1  12.0  215  29 15   7.3   4.0
 16000  -9.0  15.8  210  23 12   8.9   4.9 |  -9.9  14.2  215  28 14   8.3   4.5
 15500  -7.7  18.1  210  21 11   8.9   4.9 |  -8.7  16.3  215  26 13   8.4   4.6
 15000  -6.4  20.5  205  21 11   7.2   4.0 |  -7.4  18.7  215  23 12   9.0   4.9
 14500  -5.4  22.3  210  21 11   6.6   3.6 |  -6.0  21.2  215  21 11   9.5   5.2
 14000  -4.5  23.9  210  21 11   6.7   3.7 |  -4.6  23.7  215  19 10   9.4   5.2
 13500  -3.4  25.9  210  20 10   7.1   3.9 |  -3.2  26.2  210  19 10   9.1   5.0
 13000  -2.4  27.7  210  19 10   7.2   4.0 |  -1.8  28.8  210  19 10   9.0   4.9
 12500  -1.3  29.7  210  19 10   7.3   4.0 |  -0.6  30.9  210  19 10   7.1   3.9
 12000  -0.2  31.6  210  19 10   7.3   4.0 |   0.5  32.9  210  19 10   7.4   4.1
 11500   0.7  33.3  215  19 10   6.4   3.5 |   1.3  34.3  215  19 10   4.6   2.5
 11000   1.6  34.9  220  20 10   6.9   3.8 |   2.0  35.6  220  19 10   4.9   2.7
 10500   2.8  37.0  220  20 10   9.5   5.2 |   2.8  37.0  225  18  9   5.7   3.1
 10250   3.5  38.3  225  19 10   9.2   5.1 |   3.2  37.8  225  17  9   6.3   3.4
 10000   4.2  39.6  225  19 10   9.4   5.2 |   3.6  38.5  225  15  8   6.9   3.8
  9750   4.9  40.8  225  18  9   9.9   5.4 |   4.1  39.4  225  14  7   8.8   4.8
  9500   5.6  42.1  225  18  9  10.1   5.5 |   4.8  40.6  225  13  7  10.3   5.7
  9250   6.3  43.3  225  18 10  10.5   5.7 |   5.6  42.1  225  12  6  10.0   5.5
  9000   7.1  44.8  230  19 10   7.2   4.0 |   6.2  43.2  225  11  6   7.6   4.2
  8750   7.4  45.3  230  19 10   5.3   2.9 |   6.8  44.2  225  11  6   9.4   5.1
  8500   7.9  46.2  235  18 10   7.0   3.8 |   7.7  45.9  225  11  6  12.0   6.6
  8250   8.4  47.1  235  18  9   5.7   3.1 |   8.5  47.3  225  11  6  12.6   6.9
  8000   8.9  48.0  240  18  9   9.1   5.0 |   9.4  48.9  225  11  6   7.5   4.1
  7750   9.6  49.3  240  17  9   9.2   5.0 |   9.7  49.5  225  11  6   6.2   3.4
  7500  10.1  50.2  240  16  8   6.0   3.3 |  10.5  50.9  225  11  5  10.9   6.0
  7250  10.6  51.1  245  16  8   6.8   3.7 |  11.2  52.2  225  10  5   8.9   4.9
  7000  11.2  52.2  245  15  8   9.0   4.9 |  11.9  53.4  225  10  5  12.3   6.7
  6750  11.9  53.4  245  14  7   8.5   4.7 |  13.0  55.4  225  10  5  11.9   6.5
  6500  12.4  54.3  245  13  7   7.3   4.0 |  13.7  56.7  220  10  5   8.5   4.7
  6250  12.9  55.2  245  12  6   4.7   2.6 |  14.4  57.9  220  10  5  10.1   5.6
  6000  13.0  55.4  245  11  5  -0.8  -0.4 |  15.2  59.4  220  10  5  11.4   6.3
  5750  12.9  55.2  240   8  4  -3.2  -1.8 |  16.2  61.2  220   9  5  17.1   9.4
  5500  12.6  54.7  235   6  3  -2.6  -1.4 |  17.8  64.0  220   8  4  25.2  13.8

           03/23/2017 at 1500 MDT          |       03/23/2017 at 1800 MDT
                                           |
CAPE...     0.0    LI...       +0.9        | CAPE...     0.0    LI...       +1.0
CINH...     0.0    K Index...  -5.5        | CINH...    -0.1    K Index... +21.7
                                           |
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 -56.9 -70.4  240  18  9   3.5   1.9 | -55.8 -68.4  240  20 10   3.3   1.8
 45000 -51.6 -60.9  235  27 14   1.1   0.6 | -50.6 -59.1  240  25 13   2.0   1.1
 40000 -49.9 -57.8  215  27 14   1.1   0.6 | -47.9 -54.2  215  23 12   1.8   1.0
 38000 -49.4 -56.9  210  29 15   0.6   0.3 | -47.5 -53.5  205  24 13  -1.0  -0.6
 36000 -49.0 -56.2  210  33 17   0.6   0.3 | -48.1 -54.6  205  27 14  -1.0  -0.5
 34000 -48.6 -55.5  210  37 19   2.8   1.5 | -48.7 -55.7  200  30 15  -0.4  -0.2
 32000 -46.0 -50.8  205  42 22   3.8   2.1 | -48.0 -54.4  195  35 18   1.2   0.7
 30000 -43.6 -46.5  205  46 24   6.3   3.4 | -46.9 -52.4  195  39 20   7.1   3.9
 29000 -41.7 -43.1  205  45 23   6.0   3.3 | -44.7 -48.5  190  35 18   7.4   4.0
 28000 -39.9 -39.8  200  44 23   6.0   3.3 | -42.5 -44.5  185  32 17   7.4   4.1
 27000 -38.1 -36.6  200  43 22   6.0   3.3 | -40.3 -40.5  180  29 15   7.2   3.9
 26000 -35.9 -32.6  200  42 22   7.6   4.2 | -37.6 -35.7  180  26 13   9.5   5.2
 25000 -33.7 -28.7  200  41 21   7.6   4.2 | -34.8 -30.6  180  22 11   9.5   5.2
 24000 -31.4 -24.5  200  40 20   7.5   4.1 | -31.9 -25.4  175  19 10   9.6   5.3
 23000 -28.9 -20.0  200  38 20   8.4   4.6 | -29.2 -20.6  170  17  9   8.8   4.8
 22000 -26.4 -15.5  200  37 19   8.4   4.6 | -26.6 -15.9  170  16  8   8.8   4.8
 21000 -23.9 -11.0  205  35 18   8.3   4.5 | -24.0 -11.2  165  15  8   8.8   4.8
 20000 -21.7  -7.1  205  33 17   7.4   4.0 | -21.6  -6.9  160  14  7   7.9   4.4
 19500 -20.5  -4.9  205  32 17   7.4   4.0 | -20.5  -4.9  160  14  7   7.9   4.4
 19000 -19.4  -2.9  210  31 16   7.4   4.0 | -19.3  -2.7  160  13  7   8.0   4.4
 18500 -18.3  -0.9  210  30 16   7.3   4.0 | -18.1  -0.6  160  13  7   8.0   4.4
 18000 -16.5   2.3  210  28 14   8.4   4.6 | -17.0   1.4  160  13  7   7.6   4.2
 17500 -15.3   4.5  210  26 13   8.4   4.6 | -15.3   4.5  160  12  6   7.6   4.2
 17000 -14.0   6.8  210  24 13   8.8   4.8 | -14.2   6.4  160  11  6   7.7   4.2
 16500 -12.7   9.1  210  23 12   8.8   4.8 | -13.0   8.6  160  11  5   7.7   4.2
 16000 -11.4  11.5  210  22 11   8.7   4.8 | -11.9  10.6  165  10  5   7.3   4.0
 15500 -10.1  13.8  210  20 11   8.7   4.8 | -10.9  12.4  170   9  5   7.1   3.9
 15000  -8.7  16.3  210  19 10   8.8   4.8 |  -9.8  14.4  175   8  4   7.0   3.8
 14500  -7.4  18.7  205  18  9   9.0   4.9 |  -8.9  16.0  180   7  4   6.5   3.6
 14000  -6.1  21.0  205  16  8   9.0   4.9 |  -7.9  17.8  190   6  3   6.6   3.6
 13500  -4.7  23.5  205  15  8   9.0   4.9 |  -6.8  19.8  200   6  3   8.5   4.7
 13000  -3.4  25.9  205  14  7   9.1   5.0 |  -5.5  22.1  205   6  3   8.1   4.5
 12500  -2.1  28.2  200  13  6   8.8   4.9 |  -4.1  24.6  210   6  3  10.1   5.6
 12000  -0.8  30.6  200  11  6   8.9   4.9 |  -2.6  27.3  210   6  3  10.0   5.5
 11500   0.5  32.9  200  11  5   9.6   5.2 |  -1.1  30.0  210   6  3   9.9   5.5
 11000   1.9  35.4  200  10  5   9.4   5.2 |   0.3  32.5  210   6  3   9.9   5.4
 10500   3.4  38.1  200   9  5  10.6   5.8 |   1.9  35.4  210   6  3  11.3   6.2
 10250   4.1  39.4  200   9  5   9.9   5.4 |   2.7  36.9  210   6  3  10.4   5.7
 10000   4.8  40.6  200   9  5   8.9   4.9 |   3.5  38.3  210   6  3   9.0   4.9
  9750   5.5  41.9  200   9  5  10.2   5.6 |   4.2  39.6  210   6  3  10.1   5.5
  9500   6.4  43.5  200   9  5  11.4   6.3 |   5.0  41.0  210   6  3  11.2   6.1
  9250   7.2  45.0  200   9  5  10.9   6.0 |   5.8  42.4  210   6  3  11.2   6.2
  9000   7.9  46.2  200   9  5   7.8   4.3 |   6.6  43.9  210   6  3   7.6   4.1
  8750   8.5  47.3  205   9  5   9.1   5.0 |   7.1  44.8  215   6  3   8.8   4.8
  8500   9.3  48.7  205   9  5  11.7   6.4 |   7.9  46.2  215   6  3  12.2   6.7
  8250  10.2  50.4  205   9  4  12.2   6.7 |   8.8  47.8  215   6  3  12.4   6.8
  8000  11.0  51.8  205   9  4   7.9   4.3 |   9.7  49.5  215   6  3   8.0   4.4
  7750  11.4  52.5  205   9  4   6.6   3.6 |  10.1  50.2  215   6  3   6.9   3.8
  7500  12.1  53.8  205   8  4  10.5   5.8 |  10.8  51.4  215   6  3  11.0   6.1
  7250  12.9  55.2  205   8  4   8.7   4.8 |  11.6  52.9  215   6  3   9.7   5.3
  7000  13.6  56.5  205   8  4  11.8   6.5 |  12.4  54.3  215   6  3  11.1   6.1
  6750  14.5  58.1  205   8  4  11.6   6.4 |  13.2  55.8  215   6  3  10.6   5.8
  6500  15.3  59.5  205   8  4   8.7   4.8 |  14.0  57.2  220   6  3   9.4   5.1
  6250  16.0  60.8  205   8  4   9.7   5.3 |  14.7  58.5  220   6  3   9.6   5.3
  6000  16.7  62.1  210   8  4  11.3   6.2 |  15.4  59.7  220   6  3  10.6   5.8
  5750  17.8  64.0  210   7  4  17.8   9.8 |  16.3  61.3  220   6  3  12.0   6.6
  5500  19.4  66.9  210   7  4  24.8  13.6 |  17.1  62.8  225   5  3  11.2   6.1
________________________________________________________________________________

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.

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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