Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 210112
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1912 MDT Saturday, August 20, 2016

This forecast is for Sunday, August 21, 2016:

If the trigger temperature of 77.0 F/25.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1000 ft/min (5.1 m/s)
   Maximum height of thermals.................. 16656 ft MSL (11349 ft AGL)

Forecast maximum temperature................... 87.0 F/31.0 C
Time of trigger temperature.................... 1115 MDT
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................. 12300 ft MSL (6994 ft AGL)
Thermal soaring outlook for Monday 08/22....... 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)................ Weak NVA
Potential height of wave....................... 44927 ft MSL (39620 ft AGL)
Wave soaring outlook for Monday 08/22.......... Poor

Remarks... None

Sunrise/Sunset.................... 06:17:41 / 19:47:46 MDT
Total possible sunshine........... 13 hr 30 min 5 sec (810 min 5 sec)
Altitude of sun at 13:02:21 MDT... 62.00 degrees

Upper air data from numerical model forecast valid on 08/21/2016 at 0600 MDT

Freezing level.................. 14975 ft MSL (9668 ft AGL)
Convective condensation level... 15285 ft MSL (9978 ft AGL)
Lifted condensation level....... 15905 ft MSL (10599 ft AGL)
Lifted index.................... -3.2
K index......................... +14.6

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  -61.9 -79.4   280   30   15   0.4   0.2      M     M       M      M    M
 45000  -60.9 -77.6   285   30   15   1.7   1.0      M     M       M      M    M
 40000  -58.0 -72.4   305   29   15   6.5   3.6      M     M       M      M    M
 38000  -53.9 -65.0   305   28   14   6.8   3.7      M     M       M      M    M
 36000  -49.8 -57.6   305   27   14   6.9   3.8      M     M       M      M    M
 34000  -44.9 -48.8   305   27   14   8.7   4.8      M     M       M      M    M
 32000  -39.1 -38.4   315   27   14   8.7   4.7      M     M       M      M    M
 30000  -34.2 -29.6   315   26   13   8.0   4.4   41.1 105.9     8.0      M    M
 29000  -31.8 -25.2   320   25   13   8.0   4.4   40.4 104.8     7.6      M    M
 28000  -29.4 -20.9   320   24   12   8.1   4.4   39.9 103.8     7.3      M    M
 27000  -27.0 -16.6   320   23   12   8.1   4.4   39.1 102.5     6.8      M    M
 26000  -24.5 -12.1   320   22   11   8.1   4.4   38.5 101.3     6.3      M    M
 25000  -22.1  -7.8   325   21   11   8.1   4.5   38.0 100.4     5.9      M    M
 24000  -19.7  -3.5   320   20   10   8.0   4.4   37.3  99.1     5.4      M    M
 23000  -17.4   0.7   320   19   10   8.0   4.4   36.6  97.9     4.9      M    M
 22000  -15.0   5.0   320   18    9   8.0   4.4   36.1  96.9     4.5      M    M
 21000  -12.8   9.0   315   17    9   7.4   4.0   35.2  95.4     3.8      M    M
 20000  -10.6  12.9   315   16    8   7.4   4.1   34.4  93.9     3.1      M    M
 19500   -9.5  14.9   310   15    8   7.4   4.1   34.0  93.2     2.8      M    M
 19000   -8.4  16.9   310   15    8   6.8   3.7   33.6  92.5     2.4      M    M
 18500   -7.5  18.5   310   14    7   6.7   3.7   33.0  91.5     1.9      M    M
 18000   -6.5  20.3   310   14    7   6.7   3.7   32.5  90.5     1.4      M    M
 17500   -5.5  22.1   310   13    7   6.5   3.6   32.0  89.5     0.9      M    M
 17000   -4.6  23.7   310   12    6   6.5   3.6   31.4  88.6     0.4      M    M
 16500   -3.1  26.4   310   12    6   7.1   3.9   30.7  87.2    -0.2    974  4.9
 16000   -2.0  28.4   310   12    6   7.1   3.9   30.2  86.4    -0.6    927  4.7
 15500   -0.9  30.4   310   11    6   7.2   4.0   29.8  85.6    -1.0    880  4.5
 15000    0.2  32.4   315   11    6   7.2   4.0   29.4  84.9    -1.4    833  4.2
 14500    1.3  34.3   315   11    6   7.8   4.3   29.0  84.2    -1.8    785  4.0
 14000    2.4  36.3   315   11    6   8.0   4.4   28.7  83.6    -2.1    735  3.7
 13500    3.6  38.5   320   11    5   8.2   4.5   28.4  83.1    -2.4    685  3.5
 13000    4.8  40.6   325   10    5   8.4   4.6   28.2  82.7    -2.7    634  3.2
 12500    6.0  42.8   330    9    5   8.5   4.7   28.0  82.3    -2.9    584  3.0
 12000    7.2  45.0   330    8    4   8.6   4.7   27.8  82.0    -3.2    532  2.7
 11500    8.5  47.3   340    7    4   8.5   4.7   27.6  81.7    -3.4    480  2.4
 11000    9.6  49.3   340    6    3   7.7   4.2   27.3  81.2    -3.7    431  2.2
 10500   10.8  51.4   345    5    3   5.8   3.2   27.1  80.7    -4.1    382  1.9
 10250   11.1  52.0   345    5    3   4.7   2.6   26.6  79.9    -4.5    366  1.9
 10000   11.5  52.7   345    5    3   8.1   4.4   26.4  79.5    -4.8    344  1.7
  9750   12.1  53.8   340    4    2   9.1   5.0   26.3  79.3    -5.0    319  1.6
  9500   12.7  54.9   335    4    2   7.6   4.2   26.2  79.2    -5.1    294  1.5
  9250   13.1  55.6   325    4    2   4.4   2.4   25.9  78.6    -5.4    274  1.4
  9000   13.4  56.1   320    3    2   4.5   2.5   25.5  77.8    -5.9    259  1.3
  8750   13.7  56.7   300    3    1   5.9   3.2   25.1  77.2    -6.3    241  1.2
  8500   14.1  57.4   280    2    1   5.0   2.7   24.8  76.7    -6.7    222  1.1
  8250   14.4  57.9   265    2    1   4.2   2.3   24.4  75.9    -7.1    206  1.0
  8000   14.7  58.5   250    2    1   3.9   2.1   24.0  75.1    -7.6    191  1.0
  7750   14.9  58.8   235    2    1   3.8   2.1   23.5  74.3    -8.1    176  0.9
  7500   15.2  59.4   220    2    1   2.8   1.5   23.0  73.4    -8.6    161  0.8
  7250   15.4  59.7   225    2    1   1.9   1.1   22.4  72.4    -9.2    148  0.8
  7000   15.5  59.9   230    2    1   2.1   1.2   21.8  71.3    -9.7    135  0.7
  6750   15.7  60.3   240    2    1   1.2   0.6   21.2  70.2   -10.3    123  0.6
  6500   15.8  60.4   255    2    1   0.8   0.4   20.6  69.0   -11.0    114  0.6
  6250   15.8  60.4   260    2    1  -0.0  -0.0   19.9  67.8   -11.8    106  0.5
  6000   15.8  60.4   260    2    1   3.3   1.8   19.2  66.5   -12.5     98  0.5
  5750   16.1  61.0   265    3    1   0.1   0.0   18.7  65.7   -13.0     82  0.4
  5500   15.4  59.7   245    2    1 -15.6  -8.5   17.4  63.4   -14.4     95  0.5

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

           08/21/2016 at 0900 MDT          |       08/21/2016 at 1200 MDT
                                           |
K index... +11.8  LI... +2.5               | K index... +10.2  LI... +1.2
CAPE... 0.0  CIN... -3.0                   | CAPE... +85.3  CIN... -92.4
                                           |
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 -62.5 -80.5  280  28 14   0.4   0.2 | -62.4 -80.3  270  29 15   0.2   0.1
 45000 -61.3 -78.3  280  23 12   2.3   1.2 | -61.4 -78.5  260  27 14   2.3   1.3
 40000 -57.6 -71.7  310  17  9   6.6   3.6 | -57.6 -71.7  275  11  6   6.8   3.8
 38000 -53.7 -64.7  305  20 10   6.5   3.6 | -53.6 -64.5  290  13  7   6.6   3.6
 36000 -49.8 -57.6  300  22 11   6.6   3.6 | -49.6 -57.3  300  15  8   6.7   3.7
 34000 -44.9 -48.8  305  23 12   8.7   4.8 | -44.1 -47.4  300  17  9   8.6   4.7
 32000 -39.0 -38.2  310  23 12   8.7   4.8 | -39.0 -38.2  295  18  9   8.6   4.7
 30000 -34.0 -29.2  315  22 11   8.2   4.5 | -33.8 -28.8  300  17  9   8.5   4.7
 29000 -31.6 -24.9  320  21 11   8.2   4.5 | -31.3 -24.3  305  17  9   8.5   4.7
 28000 -29.1 -20.4  320  20 10   8.1   4.4 | -28.8 -19.8  310  16  8   8.2   4.5
 27000 -26.7 -16.1  325  20 10   8.0   4.4 | -26.4 -15.5  310  16  8   7.9   4.4
 26000 -24.3 -11.7  325  19 10   8.0   4.4 | -24.0 -11.2  310  15  8   7.9   4.4
 25000 -22.0  -7.6  325  18  9   8.0   4.4 | -21.6  -6.9  310  14  7   7.9   4.4
 24000 -19.5  -3.1  325  17  9   8.2   4.5 | -19.2  -2.6  310  14  7   8.0   4.4
 23000 -17.1   1.2  320  17  9   8.2   4.5 | -16.8   1.8  310  14  7   8.0   4.4
 22000 -14.7   5.5  320  17  9   8.1   4.5 | -14.4   6.1  305  14  7   8.0   4.4
 21000 -12.4   9.7  320  16  8   7.5   4.1 | -12.1  10.2  305  14  7   8.0   4.4
 20000 -10.2  13.6  315  16  8   7.6   4.1 |  -9.7  14.5  310  15  8   8.0   4.4
 19500  -9.1  15.6  315  16  8   7.6   4.2 |  -8.5  16.7  310  15  8   8.1   4.4
 19000  -8.0  17.6  315  16  8   6.8   3.8 |  -7.4  18.7  310  15  8   7.1   3.9
 18500  -7.0  19.4  310  15  8   6.7   3.7 |  -6.3  20.7  305  15  8   7.1   3.9
 18000  -6.0  21.2  310  15  8   6.7   3.7 |  -5.3  22.5  305  15  8   7.0   3.8
 17500  -5.1  22.8  310  14  7   6.4   3.5 |  -3.8  25.2  305  14  7   6.8   3.7
 17000  -4.1  24.6  310  14  7   6.4   3.5 |  -2.8  27.0  300  14  7   6.7   3.7
 16500  -2.7  27.1  310  13  7   6.6   3.6 |  -1.8  28.8  300  14  7   6.6   3.6
 16000  -1.7  28.9  310  12  6   6.5   3.6 |  -0.9  30.4  305  14  7   6.5   3.6
 15500  -0.7  30.7  315  12  6   7.3   4.0 |   0.1  32.2  305  13  7   7.2   3.9
 15000   0.4  32.7  315  11  6   7.3   4.0 |   1.1  34.0  305  13  7   7.1   3.9
 14500   1.5  34.7  320  11  6   7.7   4.2 |   2.2  36.0  305  12  6   7.6   4.2
 14000   2.7  36.9  320  10  5   7.8   4.3 |   3.3  37.9  305  11  6   7.8   4.3
 13500   3.8  38.8  320  10  5   7.9   4.4 |   4.5  40.1  305  10  5   7.8   4.3
 13000   5.0  41.0  325   9  5   8.0   4.4 |   5.6  42.1  305   9  5   7.8   4.3
 12500   6.2  43.2  325   9  4   8.0   4.4 |   6.8  44.2  305   8  4   7.7   4.2
 12000   7.4  45.3  330   8  4   8.0   4.4 |   7.9  46.2  305   6  3   7.6   4.2
 11500   8.5  47.3  335   7  4   8.0   4.4 |   9.1  48.4  300   5  3   7.6   4.2
 11000   9.7  49.5  340   6  3   7.9   4.3 |  10.2  50.4  300   4  2   7.4   4.1
 10500  10.9  51.6  350   5  2   4.7   2.6 |  11.4  52.5  300   3  1   4.2   2.3
 10250  11.1  52.0  355   5  2   4.4   2.4 |  11.5  52.7  300   2  1   5.2   2.8
 10000  11.7  53.1  360   4  2  10.2   5.6 |  12.2  54.0  290   1  1  10.5   5.8
  9750  12.4  54.3  010   3  2  10.9   6.0 |  12.9  55.2  260   1  0   9.5   5.2
  9500  13.1  55.6  025   3  1   9.1   5.0 |  13.7  56.7  170   1  0   9.0   4.9
  9250  13.6  56.5  035   2  1   6.0   3.3 |  14.2  57.6  150   1  1   7.6   4.2
  9000  14.0  57.2  035   2  1   6.4   3.5 |  14.8  58.6  140   2  1   8.5   4.6
  8750  14.6  58.3  035   1  1   8.0   4.4 |  15.4  59.7  140   2  1   9.4   5.2
  8500  15.1  59.2  030   1  0   5.9   3.3 |  16.1  61.0  140   3  1   8.4   4.6
  8250  15.4  59.7  000   0  0   3.8   2.1 |  16.6  61.9  145   3  2   7.8   4.3
  8000  15.6  60.1  250   1  0   3.7   2.0 |  17.1  62.8  150   3  2   7.2   3.9
  7750  15.9  60.6  235   1  1   3.5   1.9 |  17.6  63.7  155   3  1   5.9   3.3
  7500  16.0  60.8  230   2  1   2.6   1.5 |  18.0  64.4  155   3  1   7.6   4.2
  7250  16.2  61.2  230   2  1   2.0   1.1 |  18.6  65.5  145   2  1   9.1   5.0
  7000  16.3  61.3  225   2  1   2.0   1.1 |  19.2  66.6  140   2  1   8.6   4.7
  6750  16.4  61.5  225   3  1   1.6   0.9 |  19.8  67.6  130   2  1   9.3   5.1
  6500  16.5  61.7  230   3  1   1.9   1.1 |  20.5  68.9  125   2  1  10.7   5.9
  6250  16.7  62.1  240   2  1   3.5   1.9 |  21.3  70.3  125   2  1  11.9   6.5
  6000  16.9  62.4  250   2  1  -0.5  -0.3 |  22.2  72.0  125   2  1   9.5   5.2
  5750  16.9  62.4  270   2  1   6.3   3.5 |  23.0  73.4  125   2  1  14.7   8.1
  5500  18.2  64.8  275   2  1  28.6  15.7 |  24.6  76.3  115   2  1  29.7  16.3

           08/21/2016 at 1500 MDT          |       08/21/2016 at 1800 MDT
                                           |
K index... +13.2  LI... +1.4               | K index... +25.0  LI... -0.5
CAPE... +23.0  CIN... -85.7                | CAPE... +197.0  CIN... -63.3
                                           |
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 -62.7 -80.9  270  33 17   0.2   0.1 | -62.2 -80.0  270  35 18   0.3   0.2
 45000 -61.6 -78.9  260  36 19   2.3   1.3 | -61.2 -78.2  265  43 22   1.9   1.1
 40000 -57.7 -71.9  240  27 14   7.8   4.3 | -57.9 -72.2  245  54 28   8.1   4.5
 38000 -53.4 -64.1  240  22 11   7.2   4.0 | -53.3 -63.9  250  44 23   7.6   4.2
 36000 -48.5 -55.3  245  16  8   7.1   3.9 | -48.2 -54.8  255  33 17   7.5   4.1
 34000 -43.7 -46.7  250  15  8   8.2   4.5 | -43.1 -45.6  260  29 15   8.7   4.8
 32000 -38.7 -37.7  260  16  8   8.2   4.5 | -37.8 -36.0  265  25 13   8.6   4.7
 30000 -33.6 -28.5  270  15  8   8.6   4.7 | -33.0 -27.4  265  18  9   8.0   4.4
 29000 -31.0 -23.8  275  14  7   8.6   4.7 | -30.5 -22.9  270  14  7   8.0   4.4
 28000 -28.4 -19.1  280  14  7   8.3   4.6 | -28.1 -18.6  270  10  5   7.9   4.3
 27000 -26.0 -14.8  285  13  7   8.1   4.4 | -25.8 -14.4  285   9  5   7.8   4.3
 26000 -23.6 -10.5  290  13  7   8.1   4.4 | -23.5 -10.3  305   9  5   7.8   4.3
 25000 -21.2  -6.2  295  12  6   8.1   4.4 | -21.1  -6.0  320   9  5   7.8   4.3
 24000 -18.8  -1.8  300  13  7   7.8   4.3 | -18.9  -2.0  325  10  5   7.3   4.0
 23000 -16.4   2.5  300  13  7   7.9   4.3 | -16.7   1.9  325  11  6   7.3   4.0
 22000 -14.1   6.6  300  13  7   7.9   4.3 | -14.5   5.9  325  12  6   7.3   4.0
 21000 -11.8  10.8  300  14  7   7.8   4.3 | -12.3   9.9  320  13  7   7.5   4.1
 20000  -9.4  15.1  305  14  7   7.8   4.3 | -10.1  13.8  320  14  7   7.6   4.2
 19500  -8.3  17.1  305  14  7   7.9   4.3 |  -9.0  15.8  315  15  7   7.6   4.2
 19000  -7.1  19.2  310  15  8   7.6   4.1 |  -7.8  18.0  315  15  8   8.3   4.5
 18500  -6.0  21.2  310  15  8   7.5   4.1 |  -6.0  21.2  315  16  8   8.4   4.6
 18000  -4.3  24.3  310  15  8   7.6   4.1 |  -4.8  23.4  315  16  8   8.3   4.5
 17500  -3.2  26.2  310  16  8   7.6   4.2 |  -3.6  25.5  315  15  8   8.3   4.5
 17000  -2.1  28.2  310  16  8   7.6   4.2 |  -2.4  27.7  310  15  8   8.3   4.6
 16500  -1.0  30.2  310  17  9   7.6   4.2 |  -1.2  29.8  310  14  7   8.3   4.5
 16000   0.1  32.2  305  17  9   7.5   4.1 |  -0.1  31.8  305  12  6   8.5   4.6
 15500   1.2  34.2  305  17  9   8.2   4.5 |   1.0  33.8  300  10  5   7.2   4.0
 15000   2.4  36.3  305  16  8   8.2   4.5 |   2.1  35.8  290   7  4   7.3   4.0
 14500   3.6  38.5  300  15  8   7.8   4.3 |   3.1  37.6  260   5  2   7.3   4.0
 14000   4.7  40.5  300  13  7   7.7   4.2 |   4.2  39.6  205   4  2   7.4   4.0
 13500   5.8  42.4  300  11  6   7.4   4.0 |   5.3  41.5  175   7  4   7.9   4.3
 13000   6.8  44.2  300   9  4   7.1   3.9 |   6.5  43.7  165   8  4   8.6   4.7
 12500   7.8  46.0  295   6  3   7.2   3.9 |   7.8  46.0  155   9  5   8.9   4.9
 12000   8.9  48.0  270   3  2   7.5   4.1 |   9.2  48.6  150  10  5   9.8   5.4
 11500  10.0  50.0  190   2  1   7.6   4.2 |  10.6  51.1  150  10  5   9.7   5.3
 11000  11.2  52.2  160   3  2   8.1   4.5 |  12.0  53.6  145  10  5   9.2   5.0
 10500  12.4  54.3  145   5  2   5.1   2.8 |  13.4  56.1  145   9  5   5.5   3.0
 10250  12.7  54.9  145   5  3   6.6   3.6 |  13.7  56.7  145   9  5   6.7   3.7
 10000  13.4  56.1  140   5  3  11.7   6.4 |  14.6  58.3  145   9  5  12.6   6.9
  9750  14.2  57.6  140   5  3  10.6   5.8 |  15.4  59.7  145   9  5  11.4   6.2
  9500  15.0  59.0  135   5  3   9.9   5.4 |  16.3  61.3  145   9  5  10.6   5.8
  9250  15.7  60.3  135   5  3   8.6   4.7 |  17.0  62.6  145   9  5   8.7   4.8
  9000  16.3  61.3  135   5  3  10.0   5.5 |  17.6  63.7  140   9  4   9.8   5.4
  8750  17.1  62.8  135   5  3  11.1   6.1 |  18.4  65.1  140   9  4  10.8   5.9
  8500  17.9  64.2  135   5  3  10.4   5.7 |  19.2  66.6  140   9  4  10.3   5.7
  8250  18.7  65.7  135   5  3   9.7   5.3 |  20.0  68.0  140   8  4  10.0   5.5
  8000  19.4  66.9  135   5  3  10.0   5.5 |  20.7  69.3  140   8  4   9.9   5.4
  7750  20.2  68.4  135   5  3  10.6   5.8 |  21.5  70.7  140   8  4   9.9   5.5
  7500  20.9  69.6  135   5  2  10.1   5.5 |  22.2  72.0  140   8  4   9.9   5.4
  7250  21.7  71.1  135   5  2   9.7   5.3 |  22.9  73.2  140   8  4   9.8   5.4
  7000  22.4  72.3  130   5  2   9.9   5.4 |  23.7  74.7  140   8  4   9.8   5.4
  6750  23.2  73.8  130   5  2  10.4   5.7 |  24.4  75.9  135   8  4   9.7   5.3
  6500  23.9  75.0  130   5  2  10.7   5.9 |  25.1  77.2  135   7  4  10.3   5.6
  6250  24.8  76.6  130   4  2  11.3   6.2 |  26.0  78.8  135   7  4  11.0   6.0
  6000  25.6  78.1  130   4  2   9.6   5.3 |  26.8  80.2  135   7  4  10.3   5.6
  5750  26.3  79.3  130   4  2  14.1   7.7 |  27.5  81.5  135   7  4  11.3   6.2
  5500  27.9  82.2  130   4  2  27.8  15.3 |  28.5  83.3  135   7  3  16.1   8.8
________________________________________________________________________________

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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