Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 151228
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0628 MDT Wednesday, April 15, 2015

This forecast is for Wednesday, April 15, 2015:

If the trigger temperature of 62.8 F/17.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5768 ft MSL (483 ft AGL)

Forecast maximum temperature................... 57.0 F/14.3 C
Time of trigger temperature.................... None
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................. 5421 ft MSL (136 ft AGL)
Thermal soaring outlook for Thursday 04/16..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 13178 ft MSL (7893 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 13671 ft MSL (8386 ft AGL)
Wave soaring outlook for Thursday 04/16........ Poor

Remarks... Strong southwest flow at mid and upper levels today as a spring storm
           organizes itself over western colorado.

Sunrise/Sunset.................... 06:22:17 / 19:36:31 MDT
Total possible sunshine........... 13 hr 14 min 13 sec (794 min 13 sec)
Altitude of sun at 12:59:33 MDT... 60.09 degrees

Upper air data from rawinsonde observation taken on 04/15/2015 at 0600 MDT

Freezing level.................. 11273 ft MSL (5988 ft AGL)
Convective condensation level... 16575 ft MSL (11290 ft AGL)
Lifted condensation level....... 13451 ft MSL (8165 ft AGL)
Lifted index.................... +4.2
K index......................... +10.6

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  -54.4 -65.9   255   26   13   4.1   2.2  108.1 226.7    54.1      M    M
 45000  -56.0 -68.8   235   22   11   6.2   3.4   80.6 177.0    40.9      M    M
 40000  -48.0 -54.4   220   38   19 -17.3  -9.5   70.0 158.0    36.8      M    M
 38000  -58.4 -73.1   215   50   26   2.4   1.3   45.6 114.0    21.3      M    M
 36000  -54.6 -66.3   195   46   23   7.9   4.3   42.4 108.3    19.8      M    M
 34000  -53.0 -63.4   205   51   26   6.4   3.5   35.4  95.8    15.4      M    M
 32000  -51.1 -60.0   195   55   28   0.4   0.2   30.0  86.0    11.8      M    M
 30000  -46.2 -51.2   190   47   24   9.2   5.0   28.7  83.7    11.1      M    M
 29000  -43.5 -46.3   190   46   24   8.8   4.8   28.4  83.1    11.0      M    M
 28000  -40.8 -41.4   190   45   23   8.8   4.8   28.0  82.5    10.9      M    M
 27000  -38.1 -36.6   195   44   23   9.3   5.1   27.8  82.0    10.8      M    M
 26000  -35.3 -31.5   195   43   22   8.7   4.8   27.6  81.7    10.8      M    M
 25000  -32.7 -26.9   195   42   22   8.7   4.8   27.2  81.0    10.7      M    M
 24000  -30.2 -22.4   190   40   21   8.0   4.4   26.6  79.9    10.3      M    M
 23000  -29.0 -20.2   185   44   23   3.6   2.0   24.6  76.3     8.8      M    M
 22000  -26.7 -16.1   185   41   21   8.7   4.8   23.8  74.9     8.2      M    M
 21000  -23.8 -10.8   185   38   20  10.2   5.6   23.8  74.9     8.3      M    M
 20000  -21.1  -6.0   185   35   18   8.7   4.8   23.6  74.4     8.1      M    M
 19500  -19.8  -3.6   185   34   17   8.9   4.9   23.4  74.1     8.0      M    M
 19000  -18.5  -1.3   185   32   17   8.8   4.9   23.2  73.8     7.9      M    M
 18500  -17.1   1.2   185   31   16   8.8   4.8   23.1  73.5     7.8      M    M
 18000  -15.8   3.6   185   26   14   8.6   4.7   22.9  73.2     7.7      M    M
 17500  -14.6   5.7   180   24   13   8.6   4.7   22.7  72.8     7.6      M    M
 17000  -12.6   9.3   175   24   12   8.6   4.7   22.4  72.3     7.4      M    M
 16500  -11.4  11.5   175   23   12   8.6   4.7   22.2  72.0     7.2      M    M
 16000  -10.1  13.8   170   22   11   8.6   4.7   22.1  71.7     7.1      M    M
 15500   -8.8  16.2   180   19   10   8.7   4.8   21.9  71.3     7.0      M    M
 15000   -7.5  18.5   190   17    9   8.9   4.9   21.7  71.0     6.8      M    M
 14500   -6.4  20.5   210   21   11   6.3   3.5   21.3  70.3     6.5      M    M
 14000   -5.4  22.3   220   26   13   6.8   3.7   20.8  69.4     6.0      M    M
 13500   -4.7  23.5   225   29   15   2.5   1.4   20.0  68.1     5.3      M    M
 13000   -4.3  24.3   225   32   16   6.5   3.5   18.9  66.0     4.2      M    M
 12500   -3.0  26.6   230   35   18   8.5   4.7   18.7  65.7     4.1      M    M
 12000   -1.8  28.8   230   38   19   8.6   4.7   18.5  65.4     3.9      M    M
 11500   -0.5  31.1   230   35   18   8.7   4.8   18.3  65.0     3.8      M    M
 11000    0.8  33.4   235   33   17   8.7   4.8   18.1  64.6     3.6      M    M
 10500    2.1  35.8   235   31   16   8.7   4.8   18.0  64.3     3.4      M    M
 10250    2.8  37.0   240   30   15   8.7   4.8   17.9  64.2     3.3      M    M
 10000    3.4  38.1   240   29   15   8.7   4.8   17.8  64.1     3.3      M    M
  9750    4.0  39.2   240   28   14   8.8   4.8   17.7  63.9     3.2      M    M
  9500    4.7  40.5   240   28   15   8.8   4.8   17.7  63.8     3.2      M    M
  9250    5.4  41.7   235   29   15   8.8   4.8   17.6  63.7     3.1      M    M
  9000    6.0  42.8   235   29   15   8.8   4.8   17.5  63.6     3.0      M    M
  8750    6.7  44.1   235   28   15   8.8   4.8   17.5  63.4     3.0      M    M
  8500    7.3  45.1   235   27   14   8.8   4.8   17.4  63.3     2.9      M    M
  8250    8.0  46.4   230   27   14   8.8   4.8   17.3  63.2     2.8      M    M
  8000    8.6  47.5   230   26   13   8.8   4.8   17.3  63.1     2.8      M    M
  7750    9.3  48.7   230   26   14   8.9   4.9   17.2  62.9     2.7      M    M
  7500    9.9  49.8   230   27   14   8.7   4.8   17.1  62.8     2.6      M    M
  7250   10.6  51.1   230   27   14   9.3   5.1   17.0  62.7     2.5      M    M
  7000   11.2  52.2   230   28   14   5.9   3.2   16.9  62.5     2.4      M    M
  6750   11.5  52.7   230   25   13   2.7   1.5   16.4  61.6     2.0      M    M
  6500   11.7  53.1   230   23   12   3.7   2.0   16.0  60.7     1.5      M    M
  6250   12.0  53.6   235   20   10   2.9   1.6   15.5  59.9     1.0      M    M
  6000   12.2  54.0   235   17    9   5.2   2.8   15.0  59.0     0.6      M    M
  5750   12.5  54.5   235   13    7  -3.1  -1.7   14.5  58.1     0.1      M    M
  5500   11.4  52.5   235    9    5 -27.3 -15.0   12.7  54.8    -1.8      M    M

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

           04/15/2015 at 0900 MDT          |       04/15/2015 at 1200 MDT
                                           |
K index... -21.9  LI... +275.4             | K index... -8.5  LI... +275.8
CAPE... 0.0  CIN... -1.2                   | CAPE... 0.0  CIN... -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 -55.6 -68.1  255  12  6   1.9   1.1 | -55.2 -67.4  235  12  6   2.2   1.2
 45000 -52.7 -62.9  245  16  8   1.6   0.9 | -51.9 -61.4  255  16  8   2.3   1.2
 40000 -51.6 -60.9  205  26 13   0.7   0.4 | -48.3 -54.9  235  15  8   2.4   1.3
 38000 -51.4 -60.5  200  33 17  -0.8  -0.4 | -47.8 -54.0  220  19 10  -2.5  -1.4
 36000 -52.0 -61.6  200  46 24  -0.8  -0.4 | -49.5 -57.1  210  39 20  -2.6  -1.4
 34000 -52.3 -62.1  200  57 30   3.6   2.0 | -51.0 -59.8  205  57 29   0.6   0.4
 32000 -49.4 -56.9  195  62 32   4.8   2.7 | -49.0 -56.2  205  59 30   3.4   1.9
 30000 -46.4 -51.5  190  65 34   6.5   3.6 | -46.9 -52.4  205  61 31   4.8   2.6
 29000 -44.4 -47.9  190  64 33   6.7   3.7 | -45.2 -49.4  200  58 30   5.5   3.0
 28000 -42.4 -44.3  185  62 32   6.7   3.7 | -43.6 -46.5  200  56 29   5.5   3.0
 27000 -40.4 -40.7  185  60 31   6.5   3.6 | -41.9 -43.4  195  53 27   5.4   3.0
 26000 -38.1 -36.6  180  58 30   8.1   4.4 | -39.7 -39.5  195  51 26   8.3   4.5
 25000 -35.6 -32.1  185  56 29   8.1   4.4 | -37.2 -35.0  195  48 25   8.3   4.5
 24000 -33.2 -27.8  185  53 27   8.0   4.4 | -34.7 -30.5  195  46 24   8.3   4.5
 23000 -30.7 -23.3  185  50 26   8.5   4.7 | -32.1 -25.8  195  45 23   9.0   4.9
 22000 -28.2 -18.8  185  48 24   8.5   4.7 | -29.4 -20.9  200  45 23   9.0   5.0
 21000 -25.6 -14.1  185  45 23   8.5   4.6 | -26.7 -16.1  200  45 23   9.1   5.0
 20000 -23.2  -9.8  195  42 22   7.9   4.3 | -24.1 -11.4  200  43 22   8.6   4.7
 19500 -22.0  -7.6  195  41 21   7.9   4.3 | -22.8  -9.0  200  42 22   8.6   4.7
 19000 -20.8  -5.4  200  40 21   7.9   4.3 | -21.5  -6.7  200  41 21   8.6   4.7
 18500 -19.6  -3.3  205  40 21   7.7   4.2 | -19.6  -3.3  200  39 20   8.6   4.7
 18000 -17.6   0.3  205  38 20   9.4   5.1 | -18.3  -0.9  200  39 20   8.6   4.7
 17500 -16.2   2.8  210  37 19   9.4   5.2 | -17.0   1.4  200  38 20   8.7   4.8
 17000 -14.8   5.4  210  35 18   9.0   5.0 | -15.7   3.7  205  38 19   8.2   4.5
 16500 -13.5   7.7  210  34 18   9.1   5.0 | -14.5   5.9  205  38 19   8.2   4.5
 16000 -12.1  10.2  210  33 17   8.7   4.8 | -13.3   8.1  205  37 19   6.9   3.8
 15500 -10.8  12.6  210  32 17   8.6   4.7 | -12.3   9.9  210  35 18   6.4   3.5
 15000  -9.5  14.9  215  32 16   8.0   4.4 | -11.4  11.5  210  33 17   5.8   3.2
 14500  -8.4  16.9  220  32 17   7.3   4.0 | -10.7  12.7  210  29 15   4.8   2.6
 14000  -7.3  18.9  225  33 17   7.3   4.0 | -10.0  14.0  210  24 13   5.3   2.9
 13500  -6.2  20.8  225  34 18   7.1   3.9 |  -8.9  16.0  210  21 11   8.7   4.8
 13000  -5.2  22.6  230  35 18   7.1   3.9 |  -7.7  18.1  205  18  9   8.6   4.7
 12500  -4.1  24.6  235  36 19   7.2   3.9 |  -6.3  20.7  200  16  8   9.8   5.4
 12000  -3.0  26.6  240  37 19   7.2   4.0 |  -4.9  23.2  200  16  8   9.7   5.3
 11500  -2.0  28.4  240  37 19   6.9   3.8 |  -3.4  25.9  200  15  8   9.7   5.3
 11000  -1.0  30.2  245  35 18   7.0   3.9 |  -2.0  28.4  200  15  8   9.7   5.3
 10500  -0.0  32.0  245  32 17   6.6   3.6 |  -0.6  30.9  200  15  8   9.0   4.9
 10250   0.5  32.9  245  31 16   6.9   3.8 |   0.1  32.2  200  15  8   9.7   5.3
 10000   1.0  33.8  245  29 15   7.7   4.3 |   0.9  33.6  205  15  8  11.0   6.0
  9750   1.6  34.9  245  27 14   8.4   4.6 |   1.7  35.1  205  14  7  10.6   5.8
  9500   2.2  36.0  240  25 13   8.5   4.7 |   2.5  36.5  205  14  7   9.9   5.4
  9250   2.8  37.0  240  23 12   8.5   4.7 |   3.3  37.9  205  14  7  10.3   5.7
  9000   3.5  38.3  240  21 11   8.3   4.6 |   4.0  39.2  205  14  7   9.3   5.1
  8750   4.1  39.4  240  20 10   8.5   4.6 |   4.7  40.5  205  14  7   9.2   5.1
  8500   4.7  40.5  235  19 10   8.9   4.9 |   5.4  41.7  205  14  7  10.2   5.6
  8250   5.4  41.7  235  18  9   8.4   4.6 |   6.2  43.2  205  14  7   9.6   5.3
  8000   6.0  42.8  235  17  9   9.9   5.4 |   6.9  44.4  205  13  7  11.1   6.1
  7750   6.8  44.2  230  16  8   9.5   5.2 |   7.8  46.0  210  13  7  10.5   5.8
  7500   7.4  45.3  225  15  8   7.7   4.2 |   8.5  47.3  210  13  7   8.6   4.7
  7250   8.0  46.4  225  15  8   8.1   4.5 |   9.1  48.4  210  13  7   9.2   5.0
  7000   8.6  47.5  220  14  7   7.2   4.0 |   9.9  49.8  210  13  7  10.1   5.6
  6750   9.1  48.4  215  14  7   7.3   4.0 |  10.6  51.1  210  13  6  10.6   5.8
  6500   9.6  49.3  210  13  7   7.7   4.2 |  11.4  52.5  210  12  6  10.2   5.6
  6250  10.1  50.2  205  12  6   8.0   4.4 |  12.2  54.0  210  12  6  10.3   5.6
  6000  10.7  51.3  200  11  6   8.5   4.7 |  13.0  55.4  215  12  6  10.1   5.6
  5750  11.4  52.5  200  10  5   9.9   5.4 |  13.7  56.7  215  11  6  11.5   6.3
  5500  12.3  54.1  195   8  4  14.8   8.1 |  14.9  58.8  215  10  5  20.1  11.0

           04/15/2015 at 1500 MDT          |       04/15/2015 at 1800 MDT
                                           |
K index... -9.3  LI... +275.6              | K index... +6.5  LI... +274.0
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.7
                                           |
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 -55.4 -67.7  245  14  7   2.4   1.3 | -55.2 -67.4  250  12  6   2.8   1.5
 45000 -51.9 -61.4  250  17  9   2.6   1.4 | -51.1 -60.0  245  16  8   2.7   1.5
 40000 -46.7 -52.1  290   9  5   3.3   1.8 | -47.3 -53.1  255   6  3   2.4   1.3
 38000 -46.2 -51.2  250  11  6  -3.0  -1.6 | -46.9 -52.4  230  10  5  -1.8  -1.0
 36000 -47.9 -54.2  220  31 16  -2.9  -1.6 | -47.9 -54.2  220  25 13  -1.8  -1.0
 34000 -49.7 -57.5  215  54 28  -2.4  -1.3 | -49.0 -56.2  215  41 21  -1.5  -0.8
 32000 -49.2 -56.6  210  58 30   1.1   0.6 | -48.8 -55.8  210  45 23   0.6   0.3
 30000 -48.5 -55.3  210  62 32   2.4   1.3 | -48.4 -55.1  205  48 25   1.6   0.9
 29000 -46.1 -51.0  210  60 31   6.8   3.7 | -46.3 -51.3  205  49 25   6.2   3.4
 28000 -44.1 -47.4  205  59 30   6.8   3.7 | -44.4 -47.9  205  50 26   6.2   3.4
 27000 -42.0 -43.6  205  57 29   6.7   3.7 | -42.6 -44.7  205  50 26   6.1   3.3
 26000 -39.8 -39.6  205  55 28   7.8   4.3 | -40.4 -40.7  205  49 25   7.8   4.3
 25000 -37.4 -35.3  200  53 27   7.8   4.3 | -38.0 -36.4  205  48 25   7.8   4.3
 24000 -35.1 -31.2  200  50 26   7.8   4.3 | -35.7 -32.3  205  47 24   7.8   4.3
 23000 -32.6 -26.7  200  47 24   8.9   4.9 | -33.3 -27.9  205  45 23   8.3   4.5
 22000 -29.9 -21.8  200  42 22   8.9   4.9 | -30.8 -23.4  205  43 22   8.3   4.5
 21000 -27.2 -17.0  200  38 20   8.9   4.9 | -28.3 -18.9  210  41 21   8.3   4.5
 20000 -24.7 -12.5  205  37 19   8.4   4.6 | -25.9 -14.6  200  34 17   8.2   4.5
 19500 -23.4 -10.1  210  37 19   8.4   4.6 | -24.7 -12.5  200  30 16   8.2   4.5
 19000 -22.2  -8.0  215  37 19   8.4   4.6 | -23.4 -10.1  195  27 14   8.2   4.5
 18500 -20.9  -5.6  215  38 19   8.5   4.7 | -22.2  -8.0  185  24 12   8.2   4.5
 18000 -19.7  -3.5  220  37 19   7.6   4.2 | -20.8  -5.4  180  22 11  10.2   5.6
 17500 -18.5  -1.3  220  36 19   7.7   4.2 | -19.4  -2.9  175  21 11  10.0   5.5
 17000 -17.4   0.7  225  35 18   7.8   4.3 | -17.9  -0.2  170  20 10   9.6   5.3
 16500 -16.2   2.8  225  34 18   7.9   4.3 | -16.5   2.3  170  19 10   9.5   5.2
 16000 -15.0   5.0  225  33 17   8.0   4.4 | -15.1   4.8  165  19 10   9.5   5.2
 15500 -13.8   7.2  220  31 16   8.4   4.6 | -13.0   8.6  165  18  9   9.4   5.2
 15000 -11.9  10.6  220  29 15   8.1   4.5 | -11.6  11.1  165  18  9   9.5   5.2
 14500 -10.8  12.6  215  26 13   7.9   4.4 | -10.1  13.8  165  18  9   9.6   5.3
 14000  -9.6  14.7  210  24 12   8.1   4.5 |  -8.7  16.3  170  17  9   9.5   5.2
 13500  -8.4  16.9  205  21 11   8.6   4.7 |  -7.3  18.9  170  17  9   9.4   5.2
 13000  -7.1  19.2  205  18  9   8.8   4.8 |  -5.9  21.4  170  16  8   9.3   5.1
 12500  -5.7  21.7  205  16  8   9.9   5.4 |  -4.5  23.9  175  15  8   8.9   4.9
 12000  -4.3  24.3  205  15  8   9.8   5.4 |  -3.2  26.2  180  14  7   8.9   4.9
 11500  -2.8  27.0  210  15  8   9.7   5.3 |  -1.9  28.6  185  12  6   8.7   4.8
 11000  -1.4  29.5  210  14  7   9.6   5.3 |  -0.6  30.9  190  11  5   8.6   4.7
 10500   0.0  32.0  210  14  7   8.6   4.7 |   0.6  33.1  195   8  4   7.3   4.0
 10250   0.7  33.3  210  14  7   9.8   5.4 |   1.2  34.2  205   7  4   8.4   4.6
 10000   1.5  34.7  210  14  7  11.4   6.3 |   1.9  35.4  210   6  3  10.0   5.5
  9750   2.3  36.1  210  14  7  10.8   5.9 |   2.6  36.7  220   6  3  10.0   5.5
  9500   3.1  37.6  210  14  7  10.2   5.6 |   3.4  38.1  230   5  3   9.8   5.4
  9250   3.9  39.0  215  14  7  10.5   5.8 |   4.1  39.4  245   5  3   9.9   5.4
  9000   4.6  40.3  215  14  7   8.6   4.7 |   4.8  40.6  255   5  3   8.6   4.7
  8750   5.2  41.4  215  14  7   8.7   4.8 |   5.4  41.7  260   5  3   8.7   4.8
  8500   6.0  42.8  215  14  7  10.3   5.7 |   6.1  43.0  265   6  3  10.1   5.5
  8250   6.7  44.1  215  14  7   9.5   5.2 |   6.9  44.4  270   6  3   9.3   5.1
  8000   7.4  45.3  215  13  7  11.3   6.2 |   7.6  45.7  275   6  3  11.1   6.1
  7750   8.3  46.9  215  13  7  10.8   5.9 |   8.5  47.3  280   6  3  10.7   5.9
  7500   9.0  48.2  215  13  7   8.8   4.8 |   9.1  48.4  280   7  3   8.6   4.7
  7250   9.7  49.5  220  13  7   9.5   5.2 |   9.8  49.6  285   7  3   9.4   5.2
  7000  10.4  50.7  220  13  7  10.0   5.5 |  10.6  51.1  285   7  4  10.4   5.7
  6750  11.2  52.2  220  13  7  10.2   5.6 |  11.4  52.5  285   7  4  10.1   5.6
  6500  11.9  53.4  220  13  7   9.7   5.3 |  12.1  53.8  285   7  4   9.1   5.0
  6250  12.7  54.9  220  13  7  10.2   5.6 |  12.8  55.0  290   7  4   9.9   5.4
  6000  13.5  56.3  220  13  6  10.9   6.0 |  13.5  56.3  290   7  4  10.6   5.8
  5750  14.3  57.7  220  12  6  11.6   6.4 |  14.3  57.7  290   7  4  10.3   5.7
  5500  15.4  59.7  225  11  6  19.1  10.5 |  15.1  59.2  290   7  4  12.2   6.7
________________________________________________________________________________

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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