Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 150133
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1933 MDT Tuesday, April 14, 2015

This forecast is for Wednesday, April 15, 2015:

If the trigger temperature of 60.1 F/15.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6065 ft MSL (758 ft AGL)

Forecast maximum temperature................... 56.0 F/13.8 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5522 ft MSL (216 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)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 23790 ft MSL (18483 ft AGL)
Wave soaring outlook for Thursday 04/16........ Poor

Remarks... Upper trough over idaho tracks south-southeast over the four corners
           region by late on Wednesday...strengthening along the way.

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 numerical model forecast valid on 04/15/2015 at 0600 MDT

Freezing level.................. 11356 ft MSL (6049 ft AGL)
Convective condensation level... 17425 ft MSL (12118 ft AGL)
Lifted condensation level....... 13967 ft MSL (8660 ft AGL)
Lifted index.................... +4.0
K index......................... -15.9

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  -55.6 -68.1   255   15    8   2.3   1.2      M     M       M      M    M
 45000  -52.2 -62.0   255   16    8   1.3   0.7      M     M       M      M    M
 40000  -53.1 -63.6   215   23   12  -0.6  -0.3      M     M       M      M    M
 38000  -53.5 -64.3   210   31   16  -0.7  -0.4      M     M       M      M    M
 36000  -53.9 -65.0   205   44   23  -0.7  -0.4      M     M       M      M    M
 34000  -54.0 -65.2   205   57   29   4.9   2.7      M     M       M      M    M
 32000  -51.1 -60.0   205   54   28   4.9   2.7      M     M       M      M    M
 30000  -47.8 -54.0   200   52   27   8.9   4.9   26.8  80.2    10.1      M    M
 29000  -45.3 -49.5   200   50   26   8.5   4.6   26.1  79.0     9.7      M    M
 28000  -42.7 -44.9   205   48   25   8.5   4.6   25.6  78.1     9.5      M    M
 27000  -40.2 -40.4   205   47   24   8.5   4.7   25.3  77.5     9.3      M    M
 26000  -37.6 -35.7   200   46   24   8.8   4.8   24.8  76.6     9.0      M    M
 25000  -35.0 -31.0   200   46   24   8.8   4.8   24.4  75.9     8.8      M    M
 24000  -32.3 -26.1   195   45   23   8.7   4.8   24.1  75.4     8.7      M    M
 23000  -29.5 -21.1   200   45   23   9.5   5.2   23.9  75.1     8.7      M    M
 22000  -26.6 -15.9   200   44   23   9.5   5.2   23.8  74.9     8.7      M    M
 21000  -23.8 -10.8   200   44   23   9.3   5.1   23.8  74.9     8.8      M    M
 20000  -21.1  -6.0   205   42   22   8.8   4.8   23.4  74.2     8.6      M    M
 19500  -19.8  -3.6   205   41   21   8.8   4.8   23.3  73.9     8.5      M    M
 19000  -18.5  -1.3   205   40   21   8.8   4.8   23.1  73.6     8.4      M    M
 18500  -17.2   1.0   205   39   20   8.8   4.8   23.0  73.4     8.3      M    M
 18000  -15.9   3.4   205   38   20   8.7   4.8   22.8  73.1     8.2      M    M
 17500  -13.9   7.0   210   37   19   8.6   4.7   22.5  72.6     8.1      M    M
 17000  -12.7   9.1   210   36   19   8.0   4.4   22.3  72.1     7.9      M    M
 16500  -11.5  11.3   215   36   18   8.0   4.4   22.0  71.5     7.6      M    M
 16000  -10.3  13.5   215   35   18   7.6   4.2   21.7  71.0     7.4      M    M
 15500   -9.2  15.4   220   34   18   7.6   4.2   21.3  70.3     7.1      M    M
 15000   -8.0  17.6   220   34   18   7.7   4.2   20.9  69.7     6.8      M    M
 14500   -6.9  19.6   225   34   18   7.7   4.2   20.6  69.1     6.5      M    M
 14000   -5.7  21.7   225   35   18   7.8   4.3   20.3  68.5     6.3      M    M
 13500   -4.5  23.9   230   35   18   8.0   4.4   20.0  67.9     6.0      M    M
 13000   -3.3  26.1   230   36   19   7.9   4.3   19.7  67.4     5.8      M    M
 12500   -2.2  28.0   235   37   19   7.1   3.9   19.3  66.8     5.5      M    M
 12000   -1.1  30.0   240   37   19   7.1   3.9   18.9  66.0     5.1      M    M
 11500   -0.2  31.6   240   37   19   5.8   3.2   18.3  65.0     4.6      M    M
 11000    0.7  33.3   245   36   18   5.9   3.3   17.7  63.9     4.0      M    M
 10500    1.4  34.5   250   34   17   5.2   2.9   17.1  62.7     3.4      M    M
 10250    1.8  35.2   250   32   17   5.6   3.1   16.7  62.1     3.0      M    M
 10000    2.2  36.0   250   31   16   6.5   3.6   16.4  61.6     2.7      M    M
  9750    2.7  36.9   250   30   15   7.5   4.1   16.2  61.2     2.5      M    M
  9500    3.3  37.9   250   28   14   7.8   4.3   16.0  60.9     2.3      M    M
  9250    3.9  39.0   250   26   14   7.7   4.2   15.9  60.6     2.2      M    M
  9000    4.4  39.9   250   25   13   8.0   4.4   15.7  60.3     2.0      M    M
  8750    5.0  41.0   250   24   12   8.3   4.6   15.6  60.1     1.8      M    M
  8500    5.6  42.1   245   23   12   8.5   4.7   15.5  59.9     1.7      M    M
  8250    6.2  43.2   245   22   11   7.9   4.3   15.4  59.7     1.6      M    M
  8000    6.9  44.4   245   21   11  10.3   5.6   15.3  59.6     1.5      M    M
  7750    7.7  45.9   240   20   10   9.9   5.4   15.4  59.8     1.6      M    M
  7500    8.3  46.9   240   20   10   7.3   4.0   15.3  59.5     1.5      M    M
  7250    8.8  47.8   235   19   10   8.0   4.4   15.1  59.2     1.3      M    M
  7000    9.4  48.9   235   19   10   8.1   4.4   15.0  59.0     1.2      M    M
  6750   10.0  50.0   230   19   10   7.5   4.1   14.9  58.8     1.1      M    M
  6500   10.6  51.1   225   18   10   8.4   4.6   14.7  58.5     0.9      M    M
  6250   11.1  52.0   225   18    9   4.0   2.2   14.5  58.2     0.7      M    M
  6000   11.1  52.0   215   18    9  -0.9  -0.5   13.8  56.9    -0.1      M    M
  5750   10.9  51.6   210   17    9  -5.7  -3.1   12.9  55.3    -1.0      M    M
  5500    9.9  49.8   200   13    7 -18.5 -10.2   11.3  52.3    -2.7      M    M

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

           04/15/2015 at 0900 MDT          |       04/15/2015 at 1200 MDT
                                           |
K index... -16.7  LI... +277.6             | K index... -7.3  LI... +275.1
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 -55.4 -67.7  265  12  6   2.4   1.3 | -55.1 -67.2  250   8  4   3.0   1.6
 45000 -51.9 -61.4  250  11  6   2.5   1.3 | -50.6 -59.1  260  10  5   2.9   1.6
 40000 -47.8 -54.0  215  17  9   2.7   1.5 | -46.1 -51.0  235  14  7   2.9   1.6
 38000 -47.8 -54.0  210  25 13  -6.1  -3.3 | -46.6 -51.9  225  22 11  -6.9  -3.8
 36000 -52.0 -61.6  210  44 22  -6.2  -3.4 | -50.7 -59.3  215  39 20  -6.8  -3.8
 34000 -55.4 -67.7  210  59 30   2.8   1.5 | -54.8 -66.6  210  57 30  -3.0  -1.6
 32000 -52.0 -61.6  205  57 29   5.7   3.1 | -52.2 -62.0  205  61 31   4.8   2.6
 30000 -48.4 -55.1  200  56 29   8.7   4.8 | -49.3 -56.7  200  64 33   7.0   3.9
 29000 -45.8 -50.4  200  55 29   8.6   4.7 | -46.6 -51.9  195  62 32   8.8   4.8
 28000 -43.2 -45.8  200  55 28   8.6   4.7 | -43.4 -46.1  190  59 30   8.8   4.8
 27000 -40.6 -41.1  200  55 28   8.7   4.7 | -40.7 -41.3  185  57 29   8.8   4.8
 26000 -38.1 -36.6  200  52 27   8.1   4.5 | -38.1 -36.6  190  56 29   8.8   4.8
 25000 -35.7 -32.3  200  49 25   8.1   4.5 | -35.5 -31.9  190  56 29   8.8   4.8
 24000 -33.3 -27.9  200  46 24   8.1   4.4 | -32.9 -27.2  195  56 29   8.8   4.9
 23000 -30.6 -23.1  200  44 23   8.9   4.9 | -30.4 -22.7  195  53 27   8.2   4.5
 22000 -28.0 -18.4  200  43 22   8.9   4.9 | -27.9 -18.2  195  49 25   8.2   4.5
 21000 -25.3 -13.5  200  41 21   9.1   5.0 | -25.5 -13.9  195  45 23   8.2   4.5
 20000 -22.4  -8.3  200  39 20   9.6   5.3 | -23.1  -9.6  195  42 22   8.0   4.4
 19500 -21.0  -5.8  200  38 20   9.6   5.3 | -21.9  -7.4  195  41 21   8.0   4.4
 19000 -19.5  -3.1  195  37 19   9.6   5.3 | -20.7  -5.3  195  39 20   8.0   4.4
 18500 -18.1  -0.6  195  36 19   9.6   5.3 | -19.5  -3.1  195  38 19   8.0   4.4
 18000 -15.9   3.4  195  35 18   9.4   5.2 | -18.2  -0.8  195  37 19   8.2   4.5
 17500 -14.5   5.9  195  35 18   9.4   5.1 | -17.0   1.4  195  37 19   8.2   4.5
 17000 -13.1   8.4  200  34 17   9.2   5.1 | -15.8   3.6  200  36 19   8.2   4.5
 16500 -11.7  10.9  200  33 17   9.3   5.1 | -14.5   5.9  200  36 19   8.2   4.5
 16000 -10.4  13.3  200  32 17   8.3   4.5 | -13.3   8.1  205  36 19   7.6   4.2
 15500  -9.2  15.4  205  32 17   8.1   4.4 | -12.3   9.9  205  34 18   6.2   3.4
 15000  -8.0  17.6  210  32 17   7.4   4.1 | -11.0  12.2  210  31 16   5.5   3.0
 14500  -6.9  19.6  215  33 17   6.8   3.7 | -10.2  13.6  215  27 14   5.1   2.8
 14000  -5.9  21.4  220  34 18   6.5   3.6 |  -9.5  14.9  220  23 12   5.4   3.0
 13500  -5.0  23.0  230  35 18   5.9   3.2 |  -8.6  16.5  215  19 10   6.0   3.3
 13000  -4.1  24.6  235  36 18   5.9   3.2 |  -7.8  18.0  205  14  7   6.3   3.5
 12500  -3.3  26.1  240  35 18   5.4   3.0 |  -6.8  19.8  195  11  6   7.1   3.9
 12000  -2.5  27.5  245  33 17   5.5   3.0 |  -5.8  21.6  175   9  5   7.4   4.1
 11500  -1.9  28.6  250  31 16   3.2   1.7 |  -4.6  23.7  155   8  4   9.2   5.1
 11000  -1.4  29.5  255  27 14   3.5   1.9 |  -3.3  26.1  140   7  4   9.1   5.0
 10500  -0.9  30.4  260  22 11   4.5   2.5 |  -2.0  28.4  120   6  3   8.5   4.7
 10250  -0.5  31.1  265  20 10   5.0   2.8 |  -1.3  29.7  110   6  3   9.4   5.2
 10000  -0.1  31.8  265  17  9   8.0   4.4 |  -0.6  30.9  095   6  3  10.7   5.9
  9750   0.6  33.1  265  15  7   9.7   5.3 |   0.2  32.4  085   6  3  10.1   5.6
  9500   1.3  34.3  270  13  7   9.2   5.0 |   0.9  33.6  070   5  3   9.6   5.2
  9250   1.9  35.4  270  11  6   9.9   5.4 |   1.6  34.9  060   6  3   9.9   5.4
  9000   2.6  36.7  270  10  5   7.6   4.2 |   2.3  36.1  050   6  3   9.2   5.0
  8750   3.1  37.6  270   9  5   7.2   3.9 |   3.0  37.4  045   6  3   9.4   5.2
  8500   3.8  38.8  270   8  4   9.3   5.1 |   3.8  38.8  040   6  3  10.2   5.6
  8250   4.4  39.9  270   7  4   8.2   4.5 |   4.5  40.1  035   7  3  10.1   5.6
  8000   5.1  41.2  270   7  3  10.5   5.7 |   5.3  41.5  035   7  3  10.6   5.8
  7750   5.9  42.6  260   7  3   9.7   5.3 |   6.1  43.0  030   7  4  10.1   5.6
  7500   6.5  43.7  255   7  3   7.1   3.9 |   6.8  44.2  030   7  4   9.5   5.2
  7250   7.0  44.6  250   7  3   8.0   4.4 |   7.5  45.5  030   7  4   9.8   5.4
  7000   7.7  45.9  240   7  4   8.9   4.9 |   8.3  46.9  025   7  4  10.2   5.6
  6750   8.3  46.9  235   8  4   8.5   4.7 |   9.0  48.2  025   7  4   9.9   5.4
  6500   8.9  48.0  225   8  4   7.5   4.1 |   9.7  49.5  025   8  4   9.4   5.2
  6250   9.5  49.1  215   9  5   7.7   4.2 |  10.5  50.9  020   8  4  10.7   5.9
  6000  10.0  50.0  210   8  4   7.5   4.1 |  11.3  52.3  020   8  4  12.2   6.7
  5750  10.5  50.9  205   8  4   8.3   4.5 |  12.2  54.0  020   8  4  10.2   5.6
  5500  11.2  52.2  200   6  3  12.4   6.8 |  13.0  55.4  015   8  4  15.3   8.4

           04/15/2015 at 1500 MDT          |       04/15/2015 at 1800 MDT
                                           |
K index... +20.2  LI... +271.9             | K index... +21.7  LI... +272.4
CAPE... +110.8  CIN... -23.9               | CAPE... +190.0  CIN... -69.3
                                           |
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 -55.4 -67.7  255  11  6   2.7   1.5 | -55.3 -67.5  260  13  7   2.4   1.3
 45000 -51.3 -60.3  290  12  6   3.0   1.7 | -51.8 -61.2  250  14  7   2.6   1.4
 40000 -45.0 -49.0  250  12  6   4.1   2.2 | -46.2 -51.2  255  10  5   3.6   2.0
 38000 -45.0 -49.0  230  19 10  -6.5  -3.6 | -45.8 -50.4  245  12  6  -3.8  -2.1
 36000 -48.8 -55.8  220  38 19  -6.5  -3.5 | -48.0 -54.4  230  23 12  -3.7  -2.1
 34000 -52.7 -62.9  215  57 29  -4.5  -2.5 | -50.3 -58.5  225  34 18  -2.9  -1.6
 32000 -51.0 -59.8  210  60 31   3.4   1.9 | -49.9 -57.8  215  35 18   0.9   0.5
 30000 -48.9 -56.0  200  63 32   4.9   2.7 | -49.4 -56.9  205  36 18   2.7   1.5
 29000 -46.7 -52.1  200  62 32   7.7   4.2 | -46.9 -52.4  205  34 17   7.0   3.8
 28000 -43.8 -46.8  200  61 31   7.7   4.2 | -44.9 -48.8  205  32 17   7.0   3.8
 27000 -41.5 -42.7  200  60 31   7.8   4.3 | -42.8 -45.0  200  31 16   6.8   3.7
 26000 -39.3 -38.7  200  57 29   7.2   4.0 | -40.4 -40.7  200  28 14   8.2   4.5
 25000 -37.2 -35.0  200  54 28   7.2   4.0 | -38.0 -36.4  195  25 13   8.2   4.5
 24000 -35.0 -31.0  200  50 26   7.2   3.9 | -35.5 -31.9  190  22 11   8.1   4.4
 23000 -32.6 -26.7  200  47 24   8.3   4.6 | -32.9 -27.2  190  20 10   9.1   5.0
 22000 -30.1 -22.2  200  44 23   8.3   4.6 | -30.2 -22.4  190  19 10   9.1   5.0
 21000 -27.6 -17.7  195  42 21   8.3   4.5 | -27.5 -17.5  190  18  9   9.1   5.0
 20000 -25.2 -13.4  195  38 20   8.1   4.4 | -24.7 -12.5  185  17  9   9.2   5.0
 19500 -24.0 -11.2  195  36 19   8.1   4.4 | -23.4 -10.1  185  17  9   9.2   5.0
 19000 -22.8  -9.0  195  35 18   8.1   4.4 | -22.0  -7.6  185  17  9   9.2   5.0
 18500 -21.6  -6.9  195  33 17   8.1   4.5 | -20.7  -5.3  185  17  9   9.2   5.0
 18000 -20.4  -4.7  190  31 16   9.0   5.0 | -19.4  -2.9  180  17  9   8.6   4.7
 17500 -19.0  -2.2  190  30 15   9.0   4.9 | -18.1  -0.6  180  17  9   8.7   4.8
 17000 -17.7   0.1  190  28 15   8.5   4.7 | -16.8   1.8  180  18  9   8.4   4.6
 16500 -16.5   2.3  185  27 14   8.4   4.6 | -15.6   3.9  180  18  9   8.4   4.6
 16000 -15.3   4.5  185  25 13   8.5   4.7 | -14.3   6.3  180  18  9   8.4   4.6
 15500 -14.0   6.8  180  24 12   8.7   4.8 | -12.5   9.5  180  17  9   8.4   4.6
 15000 -12.1  10.2  175  21 11   8.6   4.7 | -11.2  11.8  180  16  8   8.3   4.5
 14500 -10.8  12.6  170  19 10   8.6   4.7 | -10.0  14.0  180  16  8   8.2   4.5
 14000  -9.6  14.7  170  18  9   8.7   4.7 |  -8.8  16.2  180  15  8   8.2   4.5
 13500  -8.3  17.1  165  16  8   8.7   4.8 |  -7.6  18.3  180  14  7   8.1   4.5
 13000  -7.0  19.4  155  14  7   8.6   4.7 |  -6.4  20.5  175  13  6   8.0   4.4
 12500  -5.7  21.7  150  12  6   8.5   4.7 |  -5.3  22.5  170  11  5   7.5   4.1
 12000  -4.5  23.9  140  11  6   8.4   4.6 |  -4.2  24.4  165   9  4   7.4   4.1
 11500  -3.3  26.1  125   9  4   7.9   4.3 |  -3.2  26.2  150   6  3   6.6   3.6
 11000  -2.1  28.2  095   7  4   7.8   4.3 |  -2.3  27.9  115   4  2   6.6   3.6
 10500  -1.1  30.0  065   7  4   6.9   3.8 |  -1.3  29.7  075   4  2   6.4   3.5
 10250  -0.5  31.1  050   8  4   8.4   4.6 |  -0.8  30.6  060   5  3   7.3   4.0
 10000   0.2  32.4  040   9  5  10.7   5.9 |  -0.2  31.6  045   6  3   9.1   5.0
  9750   1.0  33.8  035   9  5  10.2   5.6 |   0.5  32.9  040   7  4   9.1   5.0
  9500   1.7  35.1  030   9  5   9.6   5.3 |   1.1  34.0  035   8  4   8.5   4.7
  9250   2.4  36.3  030  10  5  10.0   5.5 |   1.7  35.1  030  10  5   8.9   4.9
  9000   3.1  37.6  025  10  5   9.0   4.9 |   2.4  36.3  025  11  6   8.1   4.4
  8750   3.8  38.8  025  10  5   9.1   5.0 |   2.9  37.2  025  12  6   8.2   4.5
  8500   4.5  40.1  020  10  5  10.1   5.5 |   3.6  38.5  025  13  7   9.1   5.0
  8250   5.3  41.5  020  10  5  10.0   5.5 |   4.3  39.7  020  14  7   9.0   4.9
  8000   6.0  42.8  020  10  5  11.0   6.0 |   5.0  41.0  020  15  7  10.1   5.5
  7750   6.9  44.4  020  10  5  10.1   5.5 |   5.7  42.3  020  15  8   9.7   5.3
  7500   7.5  45.5  015  10  5   8.8   4.8 |   6.4  43.5  025  15  8   8.7   4.8
  7250   8.2  46.8  015  11  5   9.8   5.4 |   7.1  44.8  025  16  8   9.6   5.3
  7000   9.0  48.2  015  11  5  11.1   6.1 |   7.8  46.0  025  16  8  10.9   6.0
  6750   9.8  49.6  015  11  5  10.4   5.7 |   8.6  47.5  025  16  8   9.9   5.5
  6500  10.6  51.1  015  11  5   9.4   5.1 |   9.3  48.7  025  16  8   8.8   4.8
  6250  11.3  52.3  015  11  5  10.7   5.9 |  10.0  50.0  030  16  8  10.2   5.6
  6000  12.1  53.8  010  11  5  12.1   6.6 |  10.8  51.4  030  16  8  11.2   6.1
  5750  13.0  55.4  010  10  5  10.4   5.7 |  11.6  52.9  030  15  8  10.4   5.7
  5500  13.9  57.0  010  10  5  15.3   8.4 |  12.5  54.5  030  14  7  13.3   7.3
________________________________________________________________________________

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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