Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 201316
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0716 MDT Sunday, July 20, 2014

This forecast is for Sunday, July 20, 2014:

If the trigger temperature of 89.0 F/31.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1489 ft/min (7.6 m/s)
   Maximum height of thermals.................. 20458 ft MSL (15173 ft AGL)

Forecast maximum temperature................... 97.0 F/36.6 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 15063 ft MSL (9777 ft AGL)
Thermal soaring outlook for Monday 07/21....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 16577 ft MSL (11292 ft AGL)
Wave soaring outlook for Monday 07/21.......... Poor

Remarks...

Sunrise/Sunset.................... 05:48:02 / 20:23:50 MDT
Total possible sunshine........... 14 hr 35 min 47 sec (875 min 47 sec)
Altitude of sun at 13:05:49 MDT... 70.77 degrees

Upper air data from rawinsonde observation taken on 07/20/2014 at 0600 MDT

Freezing level.................. 16375 ft MSL (11090 ft AGL)
Convective condensation level... 19574 ft MSL (14289 ft AGL)
Lifted condensation level....... 19826 ft MSL (14540 ft AGL)
Lifted index.................... -0.4
K index......................... +19.1

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  -68.7 -91.7   300   35   18   2.1   1.2   77.5 171.4    24.1      M    M
 45000  -62.3 -80.1   275   53   27   1.9   1.0   63.9 147.0    17.4      M    M
 40000  -53.4 -64.1   280   50   26   6.0   3.3   54.0 129.3    12.1      M    M
 38000  -49.4 -56.9   285   53   27   9.0   4.9   51.4 124.5    10.5      M    M
 36000  -43.9 -47.0   285   45   23   8.7   4.8   50.9 123.7    10.5      M    M
 34000  -39.5 -39.1   290   33   17   7.3   4.0   49.0 120.2     9.4      M    M
 32000  -35.0 -31.0   290   21   11   8.9   4.9   47.2 117.0     8.3      M    M
 30000  -30.4 -22.7   270   13    7   9.1   5.0   45.5 113.9     7.2      M    M
 29000  -27.7 -17.9   275   12    6   9.1   5.0   45.2 113.4     7.0      M    M
 28000  -25.2 -13.4   285   10    5   7.0   3.8   44.6 112.4     6.7      M    M
 27000  -22.9  -9.2   300    9    5   3.3   1.8   43.0 109.5     5.5      M    M
 26000  -21.1  -6.0   310    8    4   9.1   5.0   41.6 106.9     4.4      M    M
 25000  -18.4  -1.1   325    8    4   8.4   4.6   41.4 106.5     4.2      M    M
 24000  -16.0   3.2   315    8    4   8.0   4.4   40.7 105.3     3.7      M    M
 23000  -13.8   7.2   305    8    4   0.2   0.1   39.9 103.8     3.1      M    M
 22000  -12.9   8.8   300    9    4   7.4   4.1   37.4  99.3     1.0      M    M
 21000  -10.7  12.7   290    9    5   7.7   4.2   36.7  98.0     0.4      M    M
 20000   -8.3  17.1   285   10    5   9.5   5.2   36.1  97.1    -0.2   1442  7.3
 19500   -6.9  19.6   275    9    5   9.1   5.0   36.1  97.0    -0.2   1384  7.0
 19000   -5.8  21.6   265   11    6   6.8   3.7   35.7  96.3    -0.6   1337  6.8
 18500   -4.7  23.5   275   12    6   8.9   4.9   35.4  95.7    -0.9   1288  6.5
 18000   -3.4  25.9   285   13    7   9.0   4.9   35.2  95.4    -1.1   1235  6.3
 17500   -2.3  27.9   275   13    7   6.4   3.5   34.9  94.8    -1.5   1187  6.0
 17000   -1.4  29.5   265   14    7   6.7   3.7   34.4  93.9    -2.0   1145  5.8
 16500   -0.4  31.3   260   13    7   6.9   3.8   33.9  93.0    -2.6   1102  5.6
 16000    0.8  33.4   250   13    7   9.4   5.2   33.6  92.6    -2.8   1051  5.3
 15500    2.1  35.8   250   13    7   9.2   5.0   33.6  92.4    -2.9    996  5.1
 15000    3.5  38.3   245   14    7   9.2   5.0   33.5  92.3    -3.0    940  4.8
 14500    4.9  40.8   240   12    6   9.2   5.0   33.4  92.1    -3.1    884  4.5
 14000    6.2  43.2   230   10    5   9.2   5.0   33.3  92.0    -3.2    828  4.2
 13500    8.3  46.9   235    8    4   9.2   5.0   33.1  91.7    -3.4    745  3.8
 13000    9.7  49.5   240    7    4   9.2   5.0   33.0  91.5    -3.5    689  3.5
 12500   11.0  51.8   250    6    3   9.2   5.0   32.9  91.3    -3.6    633  3.2
 12000   12.4  54.3   260    6    3   9.7   5.3   32.9  91.2    -3.7    577  2.9
 11500   13.9  57.0   265    3    2   9.7   5.3   32.9  91.2    -3.7    519  2.6
 11000   15.3  59.5   290    1    1   9.6   5.3   32.9  91.2    -3.8    462  2.3
 10500   16.7  62.1   305    3    1   9.3   5.1   32.9  91.2    -3.8    404  2.1
 10250   17.3  63.1   305    3    2   8.6   4.7   32.8  91.0    -3.9    377  1.9
 10000   18.0  64.4   310    3    2   8.7   4.8   32.7  90.9    -4.0    351  1.8
  9750   18.6  65.5   310    3    2   8.7   4.7   32.6  90.7    -4.1    324  1.6
  9500   19.3  66.7   315    3    2   8.7   4.8   32.5  90.6    -4.2    297  1.5
  9250   19.9  67.8   320    3    2   8.7   4.8   32.5  90.4    -4.3    271  1.4
  9000   20.6  69.1   320    3    2   8.7   4.8   32.4  90.3    -4.4    244  1.2
  8750   21.2  70.2   305    4    2   8.7   4.7   32.3  90.2    -4.5    217  1.1
  8500   21.9  71.4   295    5    3   8.7   4.7   32.2  90.0    -4.6    191  1.0
  8250   22.5  72.5   290    6    3   8.7   4.8   32.1  89.9    -4.6    164  0.8
  8000   23.1  73.6   285    7    4   8.6   4.7   32.1  89.7    -4.7    137  0.7
  7750   23.8  74.8   285    9    5   8.8   4.8   32.0  89.5    -4.8    110  0.6
  7500   24.4  75.9   290   11    5   8.3   4.5   31.9  89.4    -4.9     84  0.4
  7250   25.1  77.2   290   12    6  10.2   5.6   31.8  89.2    -5.0     57  0.3
  7000   25.7  78.3   290   14    7   3.0   1.7   31.7  89.1    -5.1     30  0.2
  6750   25.4  77.7   275   12    6  -7.2  -4.0   30.7  87.2    -6.2     32  0.2
  6500   25.0  77.0   250   11    6  -0.7  -0.4   29.5  85.2    -7.3     37  0.2
  6250   25.3  77.5   230   12    6   9.2   5.1   29.2  84.5    -7.8     20  0.1
  6000   25.7  78.3   210   14    7  -5.6  -3.1   28.8  83.9    -8.2      2  0.0
  5750   24.2  75.6   205   10    5 -25.5 -14.0   26.7  80.1   -10.4     39  0.2
  5500   22.2  72.0   200    7    3 -22.0 -12.0   24.1  75.4   -13.2     93  0.5

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

           07/20/2014 at 0900 MDT          |       07/20/2014 at 1200 MDT
                                           |
K index... +20.9  LI... +0.8               | K index... +20.3  LI... +0.2
CAPE... 0.0  CIN... M                      | CAPE... +20.0  CIN... -75.5
                                           |
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 -64.4 -83.9  265  25 13   1.2   0.6 | -64.4 -83.9  255  28 14   1.6   0.9
 45000 -60.6 -77.1  275  43 22   5.4   3.0 | -60.3 -76.5  265  41 21   5.2   2.9
 40000 -51.8 -61.2  275  57 29   6.5   3.6 | -51.8 -61.2  270  60 31   6.3   3.5
 38000 -47.9 -54.2  280  47 24   6.5   3.6 | -48.0 -54.4  270  49 25   6.3   3.4
 36000 -44.0 -47.2  285  38 19   6.8   3.7 | -44.2 -47.6  275  38 19   7.1   3.9
 34000 -39.5 -39.1  285  32 17   7.7   4.2 | -39.2 -38.6  270  33 17   8.4   4.6
 32000 -34.9 -30.8  285  27 14   7.6   4.2 | -34.2 -29.6  270  29 15   8.8   4.8
 30000 -30.5 -22.9  275  20 11   7.3   4.0 | -29.6 -21.3  270  25 13   7.7   4.2
 29000 -28.3 -18.9  270  18  9   7.3   4.0 | -27.3 -17.1  270  23 12   7.7   4.2
 28000 -25.5 -13.9  260  14  7   7.3   4.0 | -24.5 -12.1  270  21 11   6.9   3.8
 27000 -23.4 -10.1  255  12  6   7.3   4.0 | -22.4  -8.3  260  20 10   7.0   3.8
 26000 -21.2  -6.2  245  11  5   7.3   4.0 | -20.3  -4.5  255  18  9   7.0   3.8
 25000 -19.0  -2.2  235   9  5   7.0   3.8 | -18.2  -0.8  250  17  9   6.3   3.5
 24000 -17.0   1.4  245   9  5   6.8   3.7 | -16.4   2.5  255  16  8   6.1   3.3
 23000 -14.9   5.2  255  10  5   6.8   3.7 | -14.6   5.7  260  14  7   6.1   3.3
 22000 -12.9   8.8  265  10  5   7.2   3.9 | -12.8   9.0  265  13  7   7.5   4.1
 21000 -10.8  12.6  265  13  7   7.4   4.0 | -10.4  13.3  265  14  7   7.9   4.3
 20000  -8.6  16.5  270  15  8   7.5   4.1 |  -8.1  17.4  270  15  8   8.0   4.4
 19500  -7.6  18.3  270  17  9   7.7   4.2 |  -7.0  19.4  270  16  8   8.0   4.4
 19000  -6.4  20.5  270  17  9   8.5   4.7 |  -5.8  21.6  270  17  9   8.2   4.5
 18500  -5.2  22.6  270  17  9   8.5   4.7 |  -4.6  23.7  270  17  9   8.2   4.5
 18000  -3.9  25.0  265  17  9   8.7   4.8 |  -3.4  25.9  270  18  9   8.2   4.5
 17500  -2.7  27.1  265  17  9   8.8   4.8 |  -2.2  28.0  265  18  9   8.2   4.5
 17000  -1.4  29.5  265  17  9   8.8   4.8 |  -1.0  30.2  265  17  9   8.3   4.6
 16500  -0.1  31.8  265  16  8   9.0   4.9 |   0.2  32.4  265  17  9   8.7   4.8
 16000   1.2  34.2  265  16  8   9.1   5.0 |   1.5  34.7  265  17  9   8.6   4.7
 15500   2.5  36.5  265  15  8   8.7   4.8 |   2.8  37.0  265  16  8   9.1   5.0
 15000   3.8  38.8  260  14  7   8.7   4.8 |   4.1  39.4  265  15  8   9.1   5.0
 14500   5.1  41.2  260  13  7   8.8   4.8 |   6.1  43.0  265  14  7   9.3   5.1
 14000   7.1  44.8  255  12  6   8.9   4.9 |   7.5  45.5  265  13  7   9.4   5.1
 13500   8.4  47.1  255  11  6   8.8   4.8 |   8.8  47.8  265  13  7   8.8   4.8
 13000   9.7  49.5  250  11  5   8.8   4.8 |  10.1  50.2  265  12  6   8.7   4.8
 12500  11.0  51.8  250  10  5   9.0   5.0 |  11.4  52.5  265  11  6   8.6   4.7
 12000  12.4  54.3  250   9  5   9.2   5.0 |  12.7  54.9  260  10  5   8.5   4.7
 11500  13.8  56.8  255   8  4   9.1   5.0 |  14.0  57.2  255   9  5   8.6   4.7
 11000  15.1  59.2  260   8  4   8.9   4.9 |  15.3  59.5  245   8  4   8.4   4.6
 10500  16.5  61.7  265   7  4   5.0   2.7 |  16.5  61.7  235   8  4   4.9   2.7
 10250  16.7  62.1  265   7  4   6.0   3.3 |  16.8  62.2  235   8  4   6.5   3.6
 10000  17.5  63.5  265   6  3  11.7   6.4 |  17.6  63.7  230   7  4  11.7   6.4
  9750  18.3  64.9  270   6  3  11.2   6.1 |  18.4  65.1  225   7  4  10.7   5.9
  9500  19.1  66.4  270   5  2   7.5   4.1 |  19.2  66.6  225   7  4   9.1   5.0
  9250  19.5  67.1  270   4  2   5.6   3.1 |  19.7  67.5  220   7  3   7.9   4.3
  9000  20.1  68.2  280   3  1   9.7   5.3 |  20.4  68.7  220   6  3   9.3   5.1
  8750  20.8  69.4  295   2  1  10.0   5.5 |  21.0  69.8  215   4  2   9.2   5.1
  8500  21.5  70.7  335   1  1   8.6   4.7 |  21.7  71.1  205   3  2   9.1   5.0
  8250  22.1  71.8  005   2  1   7.3   4.0 |  22.3  72.1  205   3  1   8.9   4.9
  8000  22.7  72.9  020   3  1   8.1   4.4 |  23.0  73.4  200   2  1   9.6   5.3
  7750  23.3  73.9  025   3  2   8.3   4.6 |  23.7  74.7  200   2  1  10.2   5.6
  7500  23.9  75.0  025   4  2   7.6   4.2 |  24.5  76.1  200   2  1   9.9   5.5
  7250  24.4  75.9  020   4  2   7.2   3.9 |  25.2  77.4  200   2  1   9.9   5.4
  7000  24.9  76.8  020   5  2   7.6   4.2 |  26.0  78.8  200   2  1  10.1   5.6
  6750  25.5  77.9  015   5  3   5.7   3.1 |  26.7  80.1  200   2  1  10.6   5.8
  6500  25.7  78.3  010   4  2   1.6   0.9 |  27.5  81.5  200   2  1  10.5   5.8
  6250  25.7  78.3  360   4  2   2.2   1.2 |  28.3  82.9  200   1  1  11.0   6.1
  6000  25.7  78.3  345   3  1  -2.9  -1.6 |  29.1  84.4  200   1  1   9.0   4.9
  5750  25.4  77.7  315   3  1  -0.0  -0.0 |  29.8  85.6  200   1  1  14.2   7.8
  5500  26.0  78.8  280   2  1  21.4  11.7 |  31.4  88.5  200   1  1  28.9  15.8

           07/20/2014 at 1500 MDT          |       07/20/2014 at 1800 MDT
                                           |
K index... +25.9  LI... -0.8               | K index... +25.8  LI... -1.6
CAPE... +100.0  CIN... -16.2               | CAPE... +88.3  CIN... -18.7
                                           |
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 -64.7 -84.5  250  32 16   1.8   1.0 | -65.7 -86.3  255  36 19   1.8   1.0
 45000 -60.4 -76.7  255  47 24   5.0   2.7 | -61.2 -78.2  255  56 29   5.5   3.0
 40000 -52.1 -61.8  265  71 37   7.0   3.8 | -52.1 -61.8  260  69 36   7.0   3.9
 38000 -47.9 -54.2  265  59 30   7.0   3.8 | -47.9 -54.2  255  55 28   7.0   3.9
 36000 -43.8 -46.8  265  47 24   7.4   4.1 | -43.7 -46.7  250  40 21   7.7   4.2
 34000 -38.9 -38.0  265  40 21   8.1   4.4 | -38.8 -37.8  250  34 17   8.3   4.5
 32000 -34.1 -29.4  265  34 18   8.8   4.8 | -33.8 -28.8  250  27 14   9.0   4.9
 30000 -29.4 -20.9  270  30 15   7.7   4.2 | -29.0 -20.2  255  23 12   8.0   4.4
 29000 -26.5 -15.7  270  28 14   7.7   4.2 | -26.1 -15.0  255  21 11   8.0   4.4
 28000 -24.3 -11.7  270  26 13   6.9   3.8 | -23.8 -10.8  260  19 10   7.0   3.9
 27000 -22.3  -8.1  265  24 12   7.0   3.8 | -21.7  -7.1  260  17  9   7.1   3.9
 26000 -20.2  -4.4  255  23 12   7.0   3.8 | -19.6  -3.3  255  15  8   7.1   3.9
 25000 -18.2  -0.8  250  22 11   6.7   3.7 | -17.6   0.3  255  14  7   6.6   3.6
 24000 -16.2   2.8  250  19 10   6.6   3.6 | -15.7   3.7  245  12  6   6.5   3.5
 23000 -14.3   6.3  245  17  9   6.6   3.6 | -13.8   7.2  240  11  6   6.5   3.6
 22000 -12.3   9.9  245  14  7   7.4   4.1 | -11.9  10.6  225  10  5   6.4   3.5
 21000 -10.1  13.8  250  14  7   7.6   4.2 | -10.0  14.0  215  11  6   6.4   3.5
 20000  -7.9  17.8  260  14  7   7.7   4.2 |  -8.2  17.2  205  11  6   6.4   3.5
 19500  -6.7  19.9  260  14  7   7.7   4.2 |  -7.3  18.9  205  12  6   6.6   3.6
 19000  -5.6  21.9  260  14  7   7.9   4.3 |  -6.2  20.8  200  12  6   7.1   3.9
 18500  -4.5  23.9  255  14  7   7.9   4.3 |  -5.2  22.6  195  12  6   7.0   3.8
 18000  -3.3  26.1  255  14  7   7.9   4.3 |  -4.1  24.6  195  12  6   8.3   4.6
 17500  -2.2  28.0  250  13  7   7.9   4.3 |  -2.9  26.8  195  11  6   8.6   4.7
 17000  -1.0  30.2  250  13  7   8.1   4.5 |  -1.6  29.1  195  11  5   8.9   4.9
 16500   0.2  32.4  250  12  6   8.8   4.9 |  -0.2  31.6  200  10  5   9.9   5.4
 16000   1.5  34.7  245  11  6   8.8   4.8 |   1.3  34.3  200  10  5   9.9   5.4
 15500   2.9  37.2  245  10  5   9.6   5.3 |   2.7  36.9  200   9  5   9.4   5.2
 15000   4.3  39.7  240  10  5   9.6   5.3 |   4.1  39.4  205   9  5   9.4   5.2
 14500   6.4  43.5  240   9  4   9.3   5.1 |   6.2  43.2  210   8  4   9.8   5.4
 14000   7.8  46.0  240   8  4   9.3   5.1 |   7.7  45.9  215   8  4   9.9   5.4
 13500   9.2  48.6  235   7  4   9.3   5.1 |   9.1  48.4  220   8  4   9.2   5.0
 13000  10.6  51.1  235   7  4   9.3   5.1 |  10.5  50.9  230   8  4   9.2   5.0
 12500  12.0  53.6  230   7  3   9.4   5.1 |  11.8  53.2  240   8  4   9.3   5.1
 12000  13.4  56.1  225   6  3   9.4   5.2 |  13.2  55.8  250   8  4   9.3   5.1
 11500  14.8  58.6  220   6  3   9.5   5.2 |  14.6  58.3  255   8  4   9.4   5.2
 11000  16.2  61.2  220   6  3   9.3   5.1 |  16.0  60.8  265   9  5   9.4   5.1
 10500  17.6  63.7  215   5  3   5.8   3.2 |  17.4  63.3  270  10  5   6.0   3.3
 10250  17.9  64.2  215   5  3   6.8   3.8 |  17.8  64.0  270  10  5   7.4   4.0
 10000  18.7  65.7  220   5  2  12.0   6.6 |  18.6  65.5  275  11  5  11.8   6.5
  9750  19.5  67.1  220   5  2  11.5   6.3 |  19.4  66.9  275  11  6  11.1   6.1
  9500  20.3  68.5  220   5  2   8.5   4.7 |  20.2  68.4  280  11  6   9.1   5.0
  9250  20.9  69.6  220   4  2   8.0   4.4 |  20.8  69.4  280  12  6   8.1   4.4
  9000  21.6  70.9  220   4  2  11.5   6.3 |  21.5  70.7  285  12  6  10.0   5.5
  8750  22.5  72.5  220   4  2  11.2   6.2 |  22.2  72.0  285  12  6   9.9   5.4
  8500  23.3  73.9  225   4  2  10.4   5.7 |  22.9  73.2  285  13  7   9.2   5.1
  8250  24.0  75.2  225   4  2   9.5   5.2 |  23.5  74.3  290  13  7   8.6   4.7
  8000  24.7  76.5  225   4  2   9.7   5.3 |  24.2  75.6  295  13  7   8.3   4.6
  7750  25.4  77.7  225   4  2   9.7   5.3 |  24.8  76.6  295  13  7   8.1   4.4
  7500  26.2  79.2  225   4  2   9.8   5.4 |  25.4  77.7  300  14  7   9.4   5.1
  7250  26.9  80.4  230   4  2   9.9   5.4 |  26.1  79.0  300  14  7  10.0   5.5
  7000  27.7  81.9  230   4  2  10.0   5.5 |  26.9  80.4  300  14  7  10.0   5.5
  6750  28.4  83.1  230   4  2  10.5   5.8 |  27.6  81.7  300  14  7  10.2   5.6
  6500  29.2  84.6  230   4  2  11.0   6.0 |  28.3  82.9  300  13  7  10.1   5.5
  6250  30.1  86.2  235   4  2  11.6   6.4 |  29.1  84.4  300  13  7  10.2   5.6
  6000  30.9  87.6  235   4  2   9.8   5.4 |  29.8  85.6  300  13  7   9.6   5.3
  5750  31.7  89.1  235   4  2  13.9   7.6 |  30.5  86.9  300  13  7  10.1   5.6
  5500  33.1  91.6  240   4  2  26.4  14.5 |  31.4  88.5  300  11  6  13.0   7.1
________________________________________________________________________________

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.

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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