Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 180052
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1852 MDT Monday, April 17, 2017

This forecast is for Tuesday, April 18, 2017:

If the trigger temperature of 65.1 F/18.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 830 ft/min (4.2 m/s)
   Maximum height of thermals.................. 16573 ft MSL (11266 ft AGL)

Forecast maximum temperature................... 79.0 F/26.6 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13529 ft MSL (8222 ft AGL)
Thermal soaring outlook for Wednesday 04/19.... Excellent

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 36373 ft MSL (31066 ft AGL)
Wave soaring outlook for Wednesday 04/19....... Fair

Remarks...

Sunrise/Sunset.................... 06:17:08 / 19:40:03 MDT
Total possible sunshine........... 13 hr 22 min 55 sec (802 min 55 sec)
Altitude of sun at 12:58:46 MDT... 61.33 degrees

Upper air data from numerical model forecast valid on 04/18/2017 at 0600 MDT

Freezing level.................. 12654 ft MSL (7347 ft AGL)
Convective condensation level... 16631 ft MSL (11324 ft AGL)
Lifted condensation level....... 16829 ft MSL (11523 ft AGL)
Lifted index.................... -0.3
K index......................... +11.1

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  -64.9 -84.8   300   36   19   3.3   1.8      M     M       M      M    M
 45000  -60.2 -76.4   305   58   30   1.7   0.9      M     M       M      M    M
 40000  -57.7 -71.9   300   73   37   1.7   1.0      M     M       M      M    M
 38000  -55.8 -68.4   300   72   37   3.8   2.1      M     M       M      M    M
 36000  -53.2 -63.8   295   68   35   3.8   2.1      M     M       M      M    M
 34000  -49.3 -56.7   295   64   33   8.9   4.9      M     M       M      M    M
 32000  -43.9 -47.0   295   59   30   8.9   4.9      M     M       M      M    M
 30000  -38.7 -37.7   290   50   26   8.6   4.7   37.0  98.7     8.2      M    M
 29000  -36.1 -33.0   285   45   23   8.6   4.7   36.6  97.8     8.0      M    M
 28000  -33.5 -28.3   280   40   21   8.6   4.7   36.2  97.2     7.8      M    M
 27000  -31.0 -23.8   275   37   19   7.7   4.2   35.6  96.1     7.4      M    M
 26000  -28.7 -19.7   270   35   18   7.7   4.2   34.8  94.6     6.8      M    M
 25000  -26.4 -15.5   265   34   18   7.7   4.2   34.1  93.3     6.3      M    M
 24000  -24.2 -11.6   260   33   17   7.0   3.8   33.3  91.9     5.8      M    M
 23000  -22.1  -7.8   260   31   16   7.1   3.9   32.2  90.0     4.9      M    M
 22000  -20.0  -4.0   255   29   15   7.1   3.9   31.3  88.4     4.2      M    M
 21000  -17.8  -0.0   255   28   14   7.3   4.0   30.4  86.8     3.5      M    M
 20000  -15.7   3.7   255   27   14   7.3   4.0   29.5  85.1     2.7      M    M
 19500  -14.6   5.7   255   27   14   7.3   4.0   29.1  84.4     2.3      M    M
 19000  -13.5   7.7   255   26   14   7.3   4.0   28.7  83.7     2.0      M    M
 18500  -12.4   9.7   260   26   13   7.6   4.1   28.3  83.0     1.7      M    M
 18000  -10.7  12.7   260   26   13   7.6   4.2   27.7  81.9     1.2      M    M
 17500   -9.7  14.5   260   26   13   6.6   3.6   27.3  81.1     0.8      M    M
 17000   -8.7  16.3   260   26   14   6.7   3.7   26.8  80.2     0.3      M    M
 16500   -7.7  18.1   265   26   14   6.7   3.7   26.3  79.3    -0.2    915  4.6
 16000   -6.7  19.9   265   26   14   6.7   3.7   25.7  78.3    -0.6    870  4.4
 15500   -5.7  21.7   265   26   14   6.7   3.7   25.2  77.4    -1.1    826  4.2
 15000   -4.7  23.5   265   26   14   6.7   3.7   24.7  76.5    -1.6    782  4.0
 14500   -3.7  25.3   265   26   14   6.7   3.7   24.2  75.6    -2.1    737  3.7
 14000   -2.7  27.1   265   26   13   6.8   3.7   23.7  74.7    -2.6    693  3.5
 13500   -1.7  28.9   265   26   13   6.7   3.7   23.2  73.8    -3.1    648  3.3
 13000   -0.7  30.7   265   25   13   7.7   4.2   22.8  73.1    -3.5    602  3.1
 12500    0.5  32.9   260   23   12   7.8   4.3   22.5  72.5    -3.9    553  2.8
 12000    1.5  34.7   260   21   11   6.7   3.7   22.1  71.8    -4.2    505  2.6
 11500    2.5  36.5   255   18    9   6.7   3.7   21.6  70.9    -4.7    461  2.3
 11000    3.5  38.3   250   16    8   6.1   3.3   21.1  69.9    -5.2    417  2.1
 10500    4.4  39.9   245   13    7   6.7   3.7   20.5  68.9    -5.8    375  1.9
 10250    4.9  40.8   245   12    6   3.5   1.9   20.2  68.3    -6.1    354  1.8
 10000    5.0  41.0   240   11    6   4.1   2.2   19.6  67.3    -6.7    341  1.7
  9750    5.5  41.9   240    9    5   7.5   4.1   19.4  66.8    -7.0    319  1.6
  9500    6.0  42.8   230    7    4   6.9   3.8   19.1  66.4    -7.2    297  1.5
  9250    6.5  43.7   220    5    3   5.8   3.2   18.9  66.0    -7.5    274  1.4
  9000    6.9  44.4   200    4    2   4.2   2.3   18.5  65.3    -7.9    257  1.3
  8750    7.2  45.0   160    3    2   4.5   2.5   18.1  64.6    -8.3    241  1.2
  8500    7.5  45.5   130    5    2   4.4   2.4   17.7  63.8    -8.8    224  1.1
  8250    7.8  46.0   110    6    3   5.2   2.9   17.3  63.1    -9.2    207  1.1
  8000    8.2  46.8   100    8    4   5.7   3.1   17.0  62.5    -9.6    188  1.0
  7750    8.6  47.5   095    9    5   4.6   2.5   16.6  61.9   -10.0    169  0.9
  7500    8.9  48.0   090   11    6   4.3   2.4   16.2  61.1   -10.4    153  0.8
  7250    9.2  48.6   085   12    6   4.7   2.6   15.8  60.4   -10.8    135  0.7
  7000    9.5  49.1   080   14    7   4.7   2.6   15.4  59.7   -11.3    118  0.6
  6750    9.9  49.8   075   15    8   5.2   2.9   15.0  59.1   -11.7    100  0.5
  6500   10.2  50.4   075   16    8   3.3   1.8   14.7  58.4   -12.1     82  0.4
  6250   10.4  50.7   080   14    7   0.8   0.4   14.0  57.3   -12.7     71  0.4
  6000   10.5  50.9   085   12    6   3.0   1.6   13.4  56.2   -13.3     59  0.3
  5750   10.7  51.3   090   10    5  -1.2  -0.7   12.9  55.1   -13.9     46  0.2
  5500   10.0  50.0   110    6    3 -19.2 -10.5   11.4  52.6   -15.4     61  0.3

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

           04/18/2017 at 0900 MDT          |       04/18/2017 at 1200 MDT
                                           |
K index... +8.4  LI... +3.4                | K index... +16.5  LI... +2.5
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -64.3 -83.7  305  42 21   3.0   1.6 | -64.7 -84.5  300  41 21   2.9   1.6
 45000 -60.0 -76.0  305  63 32   1.9   1.1 | -60.3 -76.5  295  64 33   2.4   1.3
 40000 -57.0 -70.6  295  86 44   1.7   0.9 | -56.8 -70.2  290  86 44   2.2   1.2
 38000 -55.0 -67.0  290  80 41   3.7   2.0 | -54.4 -65.9  285  80 41   4.1   2.3
 36000 -52.8 -63.0  285  73 37   3.7   2.0 | -52.0 -61.6  280  73 38   4.2   2.3
 34000 -49.0 -56.2  280  66 34   9.2   5.1 | -48.2 -54.8  275  65 34   8.7   4.8
 32000 -43.5 -46.3  285  59 30   9.2   5.1 | -42.9 -45.2  275  57 29   8.7   4.8
 30000 -38.3 -36.9  280  49 25   8.2   4.5 | -37.2 -35.0  275  42 22   8.4   4.6
 29000 -35.8 -32.4  275  43 22   8.2   4.5 | -34.7 -30.5  270  34 17   8.4   4.6
 28000 -32.8 -27.0  265  36 18   8.2   4.5 | -32.1 -25.8  265  26 13   8.5   4.6
 27000 -30.5 -22.9  260  34 17   7.5   4.1 | -29.9 -21.8  265  24 12   6.9   3.8
 26000 -28.3 -18.9  260  34 17   7.5   4.1 | -27.9 -18.2  265  26 13   6.8   3.8
 25000 -26.0 -14.8  260  34 17   7.5   4.1 | -25.8 -14.4  265  29 15   6.9   3.8
 24000 -23.9 -11.0  260  34 17   7.0   3.8 | -23.8 -10.8  265  31 16   7.0   3.8
 23000 -21.8  -7.2  260  33 17   7.0   3.8 | -21.7  -7.1  270  31 16   7.0   3.8
 22000 -19.7  -3.5  255  32 16   7.1   3.9 | -19.6  -3.3  270  31 16   7.0   3.8
 21000 -17.5   0.5  255  31 16   7.9   4.4 | -17.5   0.5  270  30 16   7.8   4.3
 20000 -15.1   4.8  255  30 16   8.0   4.4 | -15.2   4.6  265  29 15   7.8   4.3
 19500 -14.0   6.8  255  30 15   8.0   4.4 | -14.0   6.8  265  28 15   7.8   4.3
 19000 -12.8   9.0  250  29 15   8.0   4.4 | -12.9   8.8  260  28 14   7.8   4.3
 18500 -11.5  11.3  250  29 15   8.4   4.6 | -11.7  10.9  260  28 14   8.1   4.4
 18000 -10.3  13.5  250  29 15   8.4   4.6 | -10.5  13.1  260  28 15   8.1   4.4
 17500  -9.1  15.6  250  28 15   7.7   4.2 |  -9.3  15.3  260  29 15   8.3   4.5
 17000  -8.0  17.6  250  28 14   7.5   4.1 |  -8.1  17.4  260  29 15   8.3   4.6
 16500  -6.9  19.6  250  28 14   7.4   4.1 |  -6.8  19.8  260  28 15   8.1   4.5
 16000  -5.8  21.6  250  27 14   7.0   3.9 |  -5.8  21.6  260  28 15   6.8   3.7
 15500  -4.7  23.5  250  26 14   7.2   3.9 |  -4.3  24.3  260  28 14   6.8   3.7
 15000  -3.4  25.9  255  26 13   5.7   3.1 |  -3.3  26.1  260  28 15   6.7   3.7
 14500  -2.5  27.5  255  26 13   5.7   3.1 |  -2.3  27.9  260  28 15   6.7   3.7
 14000  -1.7  28.9  260  26 13   5.8   3.2 |  -1.3  29.7  260  28 14   6.5   3.6
 13500  -0.9  30.4  260  26 13   5.8   3.2 |  -0.4  31.3  260  27 14   6.5   3.6
 13000   0.0  32.0  265  25 13   7.0   3.8 |   0.6  33.1  260  26 13   6.6   3.6
 12500   1.0  33.8  260  24 12   6.9   3.8 |   1.5  34.7  255  24 12   6.5   3.6
 12000   2.0  35.6  260  22 11   6.3   3.4 |   2.5  36.5  255  22 12   7.1   3.9
 11500   2.9  37.2  255  20 10   6.4   3.5 |   3.6  38.5  245  21 11   7.1   3.9
 11000   3.8  38.8  245  18  9   4.3   2.4 |   4.7  40.5  240  19 10   6.9   3.8
 10500   4.4  39.9  240  16  8   4.7   2.6 |   5.7  42.3  230  19 10   7.3   4.0
 10250   4.7  40.5  235  15  8   2.5   1.4 |   6.2  43.2  225  19 10   5.1   2.8
 10000   4.8  40.6  230  15  7   2.1   1.1 |   6.5  43.7  220  19 10   5.2   2.9
  9750   5.1  41.2  225  14  7   3.9   2.1 |   7.0  44.6  215  19 10   7.4   4.1
  9500   5.3  41.5  225  13  6   3.5   1.9 |   7.6  45.7  210  18  9   7.2   4.0
  9250   5.6  42.1  215  12  6   3.3   1.8 |   8.1  46.6  205  18  9   5.9   3.2
  9000   5.8  42.4  210  11  5   3.7   2.0 |   8.4  47.1  200  18  9   3.4   1.9
  8750   6.1  43.0  205  10  5   4.4   2.4 |   8.7  47.7  195  16  8   3.2   1.7
  8500   6.4  43.5  190   9  5   4.4   2.4 |   8.9  48.0  185  15  8   3.1   1.7
  8250   6.7  44.1  180   8  4   3.8   2.1 |   9.1  48.4  180  14  7   4.5   2.5
  8000   6.9  44.4  175   8  4   3.4   1.9 |   9.5  49.1  170  12  6   6.4   3.5
  7750   7.1  44.8  170   8  4   3.7   2.0 |   9.9  49.8  165  11  6   7.0   3.8
  7500   7.4  45.3  170   8  4   4.1   2.2 |  10.5  50.9  160  10  5   8.1   4.5
  7250   7.7  45.9  160   8  4   4.5   2.4 |  11.1  52.0  155  10  5  10.0   5.5
  7000   8.0  46.4  150   8  4   4.7   2.6 |  11.9  53.4  155  10  5  10.8   5.9
  6750   8.4  47.1  140   9  5   3.3   1.8 |  12.7  54.9  155   9  5   8.7   4.8
  6500   8.6  47.5  135  10  5   5.9   3.3 |  13.3  55.9  155   9  5   9.7   5.3
  6250   9.3  48.7  135   8  4   9.4   5.1 |  14.1  57.4  155   9  5  12.2   6.7
  6000   9.9  49.8  135   7  4   7.7   4.2 |  15.0  59.0  155   8  4  11.1   6.1
  5750  10.6  51.1  135   6  3  10.8   5.9 |  15.8  60.4  155   8  4  11.8   6.5
  5500  11.7  53.1  135   6  3  18.3  10.0 |  16.9  62.4  155   8  4  18.3  10.1

           04/18/2017 at 1500 MDT          |       04/18/2017 at 1800 MDT
                                           |
K index... +14.6  LI... +1.2               | K index... +24.8  LI... -0.6
CAPE... +0.2  CIN... -2.1                  | CAPE... +18.8  CIN... -14.2
                                           |
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 -64.9 -84.8  285  41 21   3.3   1.8 | -64.7 -84.5  265  41 21   3.5   1.9
 45000 -60.1 -76.2  285  66 34   1.7   0.9 | -59.5 -75.1  275  68 35   2.4   1.3
 40000 -57.5 -71.5  275  85 44   1.3   0.7 | -55.9 -68.6  270  88 45   2.2   1.2
 38000 -54.8 -66.6  275  77 40   5.0   2.7 | -53.4 -64.1  270  82 42   4.5   2.4
 36000 -51.8 -61.2  270  67 35   5.0   2.7 | -50.7 -59.3  265  74 38   4.5   2.4
 34000 -47.7 -53.9  265  61 31   8.9   4.9 | -47.1 -52.8  260  68 35   7.9   4.3
 32000 -42.4 -44.3  270  58 30   8.9   4.9 | -41.8 -43.2  260  62 32   7.9   4.3
 30000 -36.4 -33.5  265  49 25   8.8   4.8 | -37.1 -34.8  265  57 29   7.8   4.3
 29000 -33.8 -28.8  265  44 23   8.8   4.8 | -34.8 -30.6  265  54 28   7.8   4.3
 28000 -31.1 -24.0  260  39 20   8.9   4.9 | -32.5 -26.5  265  52 27   7.8   4.3
 27000 -29.0 -20.2  255  36 19   5.7   3.1 | -30.2 -22.4  265  49 25   7.6   4.2
 26000 -27.3 -17.1  250  36 19   5.6   3.1 | -27.8 -18.0  255  46 23   7.6   4.2
 25000 -25.7 -14.3  245  36 19   5.6   3.1 | -25.5 -13.9  250  43 22   7.6   4.2
 24000 -23.8 -10.8  240  36 18   7.6   4.2 | -23.3  -9.9  245  42 22   7.2   3.9
 23000 -21.5  -6.7  240  34 18   7.5   4.1 | -21.1  -6.0  245  43 22   7.2   4.0
 22000 -19.2  -2.6  245  32 17   7.6   4.2 | -19.0  -2.2  250  44 23   7.2   3.9
 21000 -17.0   1.4  250  32 16   7.3   4.0 | -17.0   1.4  255  44 23   5.5   3.0
 20000 -14.8   5.4  255  33 17   7.3   4.0 | -15.4   4.3  255  42 21   5.6   3.1
 19500 -13.7   7.3  255  34 17   7.4   4.0 | -14.6   5.7  255  40 21   5.6   3.1
 19000 -12.6   9.3  260  35 18   7.4   4.1 | -13.7   7.3  255  39 20   5.6   3.1
 18500 -11.5  11.3  260  34 18   7.4   4.0 | -12.8   9.0  255  38 19   7.3   4.0
 18000 -10.4  13.3  260  33 17   7.4   4.1 | -11.8  10.8  260  36 18   7.2   4.0
 17500  -9.3  15.3  260  32 16   7.3   4.0 | -10.7  12.7  260  34 17   7.4   4.0
 17000  -8.3  17.1  260  32 16   7.3   4.0 |  -9.7  14.5  255  32 17   7.6   4.1
 16500  -7.2  19.0  265  32 16   7.3   4.0 |  -8.1  17.4  255  30 15   8.4   4.6
 16000  -5.7  21.7  265  31 16   6.8   3.7 |  -6.8  19.8  250  27 14   8.7   4.8
 15500  -4.7  23.5  265  30 16   6.9   3.8 |  -5.6  21.9  245  25 13   9.1   5.0
 15000  -3.7  25.3  260  28 15   7.0   3.9 |  -4.2  24.4  245  24 12   9.8   5.4
 14500  -2.7  27.1  260  26 14   7.2   3.9 |  -2.7  27.1  240  23 12   9.8   5.4
 14000  -1.7  28.9  255  24 12   7.5   4.1 |  -1.3  29.7  240  23 12   9.2   5.0
 13500  -0.6  30.9  245  21 11   7.3   4.0 |   0.1  32.2  240  22 12   9.1   5.0
 13000   0.5  32.9  235  20 10   8.6   4.7 |   1.5  34.7  235  22 11   9.8   5.4
 12500   1.7  35.1  225  19 10   8.5   4.7 |   2.9  37.2  235  21 11   9.9   5.4
 12000   3.0  37.4  220  19 10   9.4   5.1 |   4.4  39.9  230  20 10   9.2   5.1
 11500   4.4  39.9  220  18  9   9.4   5.2 |   5.7  42.3  230  19 10   9.2   5.1
 11000   5.8  42.4  215  18  9   8.1   4.5 |   7.1  44.8  230  19 10   8.3   4.5
 10500   7.0  44.6  215  17  9   7.1   3.9 |   8.3  46.9  225  18  9   7.8   4.3
 10250   7.6  45.7  210  17  9  12.0   6.6 |   9.0  48.2  225  17  9  11.4   6.2
 10000   8.6  47.5  210  17  9  12.7   7.0 |   9.9  49.8  225  16  8  11.4   6.2
  9750   9.3  48.7  210  16  8   8.3   4.5 |  10.6  51.1  220  16  8   8.2   4.5
  9500  10.0  50.0  210  15  8   9.7   5.3 |  11.2  52.2  220  15  8   9.2   5.0
  9250  10.7  51.3  210  15  8   8.3   4.6 |  11.9  53.4  220  14  7   8.6   4.7
  9000  11.3  52.3  205  14  7   8.6   4.7 |  12.5  54.5  220  13  7   9.0   4.9
  8750  12.0  53.6  205  13  7   9.8   5.4 |  13.2  55.8  220  13  6   9.8   5.4
  8500  12.7  54.9  205  12  6   9.5   5.2 |  14.0  57.2  220  12  6   9.1   5.0
  8250  13.4  56.1  205  12  6   9.3   5.1 |  14.7  58.5  220  11  6  11.1   6.1
  8000  14.1  57.4  205  11  6   9.0   4.9 |  15.6  60.1  220  10  5  11.2   6.2
  7750  14.8  58.6  210  10  5   9.0   4.9 |  16.3  61.3  220  10  5   9.1   5.0
  7500  15.4  59.7  210  10  5   9.1   5.0 |  17.0  62.6  220  10  5   9.2   5.1
  7250  16.1  61.0  210   9  5  10.2   5.6 |  17.7  63.9  220   9  5   9.9   5.5
  7000  16.9  62.4  210   9  5  10.6   5.8 |  18.4  65.1  225   9  5  10.3   5.7
  6750  17.7  63.9  215   9  5   9.3   5.1 |  19.2  66.6  225   9  5   9.2   5.1
  6500  18.4  65.1  215   9  5   9.8   5.4 |  19.9  67.8  225   9  4   9.4   5.2
  6250  19.2  66.6  215   8  4  11.2   6.2 |  20.6  69.1  225   8  4  10.6   5.8
  6000  20.0  68.0  215   8  4  11.2   6.1 |  21.4  70.5  225   8  4  11.1   6.1
  5750  20.8  69.4  220   8  4  10.6   5.8 |  22.2  72.0  225   7  4   9.4   5.1
  5500  21.7  71.1  220   7  4  14.6   8.0 |  22.9  73.2  230   7  3   9.1   5.0
________________________________________________________________________________

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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