Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 250128
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1928 MDT Wednesday, June 24, 2015

This forecast is for Thursday, June 25, 2015:

If the trigger temperature of 85.0 F/29.5 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 222 ft/min (1.1 m/s)
   Maximum height of thermals.................. 10777 ft MSL (5470 ft AGL)

Forecast maximum temperature................... 87.0 F/31.0 C
Time of trigger temperature.................... 1330 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7503 ft MSL (2197 ft AGL)
Thermal soaring outlook for Friday 06/26....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 17124 ft MSL (11817 ft AGL)
Wave soaring outlook for Friday 06/26.......... Poor

Remarks... Moist airmass will become unstable in the afternoon with
           thunderstorms and heavy rain developing.

Sunrise/Sunset.................... 05:32:47 / 20:31:22 MDT
Total possible sunshine........... 14 hr 58 min 34 sec (898 min 34 sec)
Altitude of sun at 13:02:10 MDT... 73.58 degrees

Upper air data from numerical model forecast valid on 06/25/2015 at 0600 MDT

Freezing level.................. 16224 ft MSL (10917 ft AGL)
Convective condensation level... 16318 ft MSL (11011 ft AGL)
Lifted condensation level....... 15546 ft MSL (10239 ft AGL)
Lifted index.................... -2.4
K index......................... +21.6

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  -64.4 -83.9   280   40   21   2.0   1.1      M     M       M      M    M
 45000  -60.3 -76.5   275   49   25   4.0   2.2      M     M       M      M    M
 40000  -54.0 -65.2   270   37   19   5.9   3.2      M     M       M      M    M
 38000  -50.4 -58.7   265   32   17   5.9   3.2      M     M       M      M    M
 36000  -46.9 -52.4   255   28   14   5.6   3.1      M     M       M      M    M
 34000  -41.8 -43.2   255   25   13   8.9   4.9      M     M       M      M    M
 32000  -35.8 -32.4   250   22   12   9.2   5.0      M     M       M      M    M
 30000  -31.1 -24.0   255   19   10   7.9   4.3   44.2 111.6    10.4      M    M
 29000  -28.7 -19.7   255   17    9   7.9   4.3   43.6 110.4    10.0      M    M
 28000  -26.4 -15.5   260   15    8   7.3   4.0   42.9 109.2     9.6      M    M
 27000  -24.2 -11.6   265   13    7   7.3   4.0   41.9 107.4     8.8      M    M
 26000  -22.1  -7.8   275   12    6   7.3   4.0   41.0 105.7     8.2      M    M
 25000  -19.9  -3.8   290   10    5   7.3   4.0   40.2 104.3     7.6      M    M
 24000  -17.8  -0.0   290   10    5   7.1   3.9   39.1 102.4     6.8      M    M
 23000  -15.6   3.9   290   10    5   7.1   3.9   38.1 100.7     6.1      M    M
 22000  -13.5   7.7   295   10    5   7.1   3.9   37.3  99.1     5.5      M    M
 21000  -11.5  11.3   300    9    5   7.1   3.9   36.2  97.2     4.6      M    M
 20000   -9.4  15.1   310    9    4   7.1   3.9   35.3  95.6     3.8      M    M
 19500   -8.4  16.9   315    8    4   7.2   3.9   34.9  94.8     3.4      M    M
 19000   -7.2  19.0   320    9    4   8.2   4.5   34.6  94.2     3.1      M    M
 18500   -6.0  21.2   320    9    5   8.1   4.5   34.3  93.7     2.8      M    M
 18000   -4.8  23.4   320   10    5   8.1   4.5   34.0  93.2     2.6      M    M
 17500   -3.6  25.5   325   11    6   8.2   4.5   33.7  92.7     2.3      M    M
 17000   -1.8  28.8   325   12    6   9.0   4.9   33.4  92.0     2.0      M    M
 16500   -0.5  31.1   325   12    6   9.4   5.2   33.3  91.9     1.9      M    M
 16000    0.9  33.6   330   13    6   9.4   5.2   33.2  91.8     1.8      M    M
 15500    2.3  36.1   330   13    7   9.1   5.0   33.1  91.7     1.7      M    M
 15000    3.6  38.5   330   13    7   9.2   5.0   33.0  91.5     1.6      M    M
 14500    5.0  41.0   330   13    7   8.8   4.8   32.9  91.3     1.5      M    M
 14000    6.3  43.3   330   13    7   8.8   4.8   32.8  91.0     1.3      M    M
 13500    7.5  45.5   325   13    7   8.7   4.8   32.6  90.7     1.2      M    M
 13000    8.8  47.8   325   13    7   8.7   4.8   32.4  90.4     1.0      M    M
 12500   10.1  50.2   320   13    7   8.5   4.7   32.3  90.1     0.8      M    M
 12000   11.3  52.3   315   13    7   8.4   4.6   32.0  89.7     0.6      M    M
 11500   12.6  54.7   315   12    6   8.2   4.5   31.8  89.3     0.4      M    M
 11000   13.8  56.8   310   12    6   7.7   4.2   31.6  88.8     0.1      M    M
 10500   14.9  58.8   305   11    6   3.6   2.0   31.3  88.3    -0.2    392  2.0
 10250   15.0  59.0   305   11    6   4.7   2.6   30.6  87.2    -0.8    381  1.9
 10000   15.7  60.3   300   10    5  10.9   6.0   30.6  87.1    -0.8    353  1.8
  9750   16.4  61.5   300   10    5   9.8   5.4   30.6  87.1    -0.8    324  1.6
  9500   17.1  62.8   295   10    5   8.2   4.5   30.6  87.1    -0.9    296  1.5
  9250   17.6  63.7   295    9    5   6.1   3.3   30.4  86.7    -1.1    274  1.4
  9000   18.1  64.6   290    9    5   7.8   4.3   30.2  86.3    -1.3    251  1.3
  8750   18.7  65.7   290    8    4   9.0   4.9   30.1  86.1    -1.5    226  1.1
  8500   19.3  66.7   285    8    4   7.0   3.9   30.0  85.9    -1.6    201  1.0
  8250   19.7  67.5   285    7    4   5.3   2.9   29.7  85.4    -1.9    181  0.9
  8000   20.2  68.4   285    7    4   5.8   3.2   29.3  84.8    -2.2    161  0.8
  7750   20.6  69.1   285    7    4   5.7   3.1   29.0  84.3    -2.6    141  0.7
  7500   20.9  69.6   280    7    3   3.9   2.2   28.7  83.6    -3.0    123  0.6
  7250   21.1  70.0   280    6    3   2.5   1.4   28.1  82.7    -3.5    111  0.6
  7000   21.3  70.3   275    6    3   3.6   2.0   27.6  81.7    -4.1     99  0.5
  6750   21.4  70.5   270    6    3   0.6   0.3   27.1  80.8    -4.7     86  0.4
  6500   21.2  70.2   270    6    3  -5.1  -2.8   26.2  79.1    -5.7     87  0.4
  6250   20.6  69.1   270    6    3  -7.5  -4.1   24.9  76.9    -7.0     97  0.5
  6000   20.0  68.0   270    6    3  -3.4  -1.8   23.7  74.7    -8.4    107  0.5
  5750   19.6  67.3   280    6    3  -9.7  -5.3   22.7  72.9    -9.5    111  0.6
  5500   17.8  64.0   260    5    2 -30.1 -16.5   20.5  68.8   -12.0    157  0.8

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

           06/25/2015 at 0900 MDT          |       06/25/2015 at 1200 MDT
                                           |
K index... +24.5  LI... -1.5               | K index... +21.4  LI... -4.9
CAPE... +302.8  CIN... -225.4              | CAPE... +1414.6  CIN... -68.9
                                           |
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 -63.4 -82.1  285  37 19   1.4   0.8 | -63.7 -82.7  285  30 15   2.1   1.1
 45000 -60.3 -76.5  285  45 23   3.7   2.0 | -60.1 -76.2  295  33 17   3.1   1.7
 40000 -54.4 -65.9  285  34 17   6.3   3.5 | -54.8 -66.6  310  28 14   6.7   3.7
 38000 -50.5 -58.9  285  28 14   6.4   3.5 | -50.7 -59.3  315  25 13   6.8   3.7
 36000 -46.6 -51.9  285  22 11   6.3   3.5 | -46.0 -50.8  320  22 12   7.4   4.1
 34000 -41.4 -42.5  280  20 10   8.0   4.4 | -41.0 -41.8  325  20 10   8.4   4.6
 32000 -36.6 -33.9  270  20 10   8.2   4.5 | -35.9 -32.6  325  18  9   8.5   4.7
 30000 -31.8 -25.2  275  18  9   8.0   4.4 | -31.0 -23.8  325  17  9   8.1   4.4
 29000 -29.4 -20.9  280  16  8   8.0   4.4 | -28.6 -19.5  320  17  9   8.1   4.4
 28000 -27.1 -16.8  280  15  8   7.5   4.1 | -26.2 -15.2  320  16  8   7.3   4.0
 27000 -24.8 -12.6  280  13  7   7.5   4.1 | -24.1 -11.4  315  16  8   7.3   4.0
 26000 -22.6  -8.7  285  12  6   7.5   4.1 | -21.9  -7.4  310  15  8   7.4   4.1
 25000 -20.3  -4.5  285  11  5   7.2   3.9 | -19.7  -3.5  305  15  8   7.2   3.9
 24000 -18.4  -1.1  285   9  5   6.5   3.6 | -17.7   0.1  300  15  8   6.7   3.7
 23000 -16.5   2.3  290   8  4   6.6   3.6 | -15.7   3.7  295  15  8   6.8   3.7
 22000 -14.5   5.9  295   7  4   7.2   4.0 | -13.8   7.2  290  15  8   6.9   3.8
 21000 -12.2  10.0  295   6  3   7.9   4.4 | -11.7  10.9  285  14  7   7.0   3.8
 20000  -9.8  14.4  290   5  3   8.0   4.4 |  -9.6  14.7  285  14  7   7.0   3.8
 19500  -8.7  16.3  290   5  3   8.0   4.4 |  -8.6  16.5  280  14  7   7.0   3.8
 19000  -7.5  18.5  295   5  3   8.1   4.4 |  -7.5  18.5  280  13  7   7.8   4.3
 18500  -6.3  20.7  305   5  3   8.1   4.4 |  -6.3  20.7  280  13  7   7.8   4.3
 18000  -5.1  22.8  315   5  3   8.1   4.4 |  -4.6  23.7  280  12  6   7.8   4.3
 17500  -4.0  24.8  325   6  3   8.1   4.5 |  -3.5  25.7  280  12  6   7.8   4.3
 17000  -2.2  28.0  330   6  3   8.8   4.8 |  -2.3  27.9  280  11  6   8.7   4.7
 16500  -0.9  30.4  335   7  4   9.0   5.0 |  -1.0  30.2  280  11  6   9.0   5.0
 16000   0.4  32.7  340   8  4   9.1   5.0 |   0.4  32.7  285  11  6   9.0   5.0
 15500   1.8  35.2  340   9  5   9.3   5.1 |   1.7  35.1  290  11  6   8.9   4.9
 15000   3.1  37.6  345  10  5   9.3   5.1 |   3.0  37.4  300  11  6   8.8   4.8
 14500   4.5  40.1  345  11  5   9.4   5.2 |   4.4  39.9  305  12  6   9.5   5.2
 14000   5.9  42.6  340  11  6   9.4   5.2 |   5.8  42.4  310  13  7   9.4   5.2
 13500   7.3  45.1  340  12  6   9.4   5.1 |   7.2  45.0  315  13  7   9.4   5.1
 13000   8.7  47.7  340  13  7   9.4   5.1 |   8.6  47.5  315  14  7   9.4   5.2
 12500  10.1  50.2  340  14  7   9.2   5.0 |   9.9  49.8  320  14  7   9.0   5.0
 12000  11.5  52.7  335  15  8   9.0   5.0 |  11.2  52.2  325  14  7   8.9   4.9
 11500  12.8  55.0  335  15  8   8.9   4.9 |  12.5  54.5  330  13  7   8.7   4.8
 11000  14.1  57.4  335  16  8   8.5   4.6 |  13.7  56.7  335  13  7   8.3   4.5
 10500  15.4  59.7  330  16  8   3.8   2.1 |  15.0  59.0  340  13  7   4.1   2.3
 10250  15.5  59.9  330  16  8   4.7   2.6 |  15.1  59.2  340  13  6   5.1   2.8
 10000  16.3  61.3  330  16  8  11.5   6.3 |  15.9  60.6  340  12  6  11.1   6.1
  9750  17.0  62.6  330  15  8  10.4   5.7 |  16.6  61.9  340  12  6  10.4   5.7
  9500  17.8  64.0  325  15  8   8.1   4.4 |  17.3  63.1  340  11  6   6.9   3.8
  9250  18.2  64.8  325  15  8   5.5   3.0 |  17.6  63.7  345  11  6   3.4   1.9
  9000  18.7  65.7  325  14  7   7.8   4.3 |  18.0  64.4  345  10  5   5.9   3.2
  8750  19.3  66.7  325  13  7   8.5   4.7 |  18.4  65.1  350   9  5   6.5   3.6
  8500  19.9  67.8  325  13  7   7.3   4.0 |  18.8  65.8  355   8  4   4.8   2.6
  8250  20.4  68.7  325  12  6   6.4   3.5 |  19.0  66.2  005   7  3   3.6   2.0
  8000  20.8  69.4  320  12  6   6.4   3.5 |  19.2  66.6  020   6  3   4.1   2.2
  7750  21.3  70.3  320  11  6   5.8   3.2 |  19.4  66.9  035   5  3   5.2   2.8
  7500  21.7  71.1  320  10  5   4.7   2.6 |  19.8  67.6  040   5  3   8.3   4.5
  7250  22.0  71.6  320  10  5   4.1   2.3 |  20.4  68.7  045   5  3   9.7   5.3
  7000  22.3  72.1  320   9  5   4.0   2.2 |  21.0  69.8  045   5  3   9.8   5.4
  6750  22.5  72.5  325   9  5   2.4   1.3 |  21.7  71.1  045   5  3  10.5   5.8
  6500  22.5  72.5  325   8  4   1.0   0.5 |  22.4  72.3  045   5  3  10.4   5.7
  6250  22.5  72.5  330   6  3   2.4   1.3 |  23.2  73.8  045   5  3  10.2   5.6
  6000  22.5  72.5  335   4  2  -1.9  -1.0 |  24.0  75.2  045   5  3  10.7   5.9
  5750  22.1  71.8  025   2  1   3.9   2.1 |  25.0  77.0  040   5  2  17.3   9.5
  5500  23.3  73.9  030   2  1  26.3  14.4 |  26.6  79.9  040   5  3  26.4  14.5

           06/25/2015 at 1500 MDT          |       06/25/2015 at 1800 MDT
                                           |
K index... +24.6  LI... -6.3               | K index... +32.5  LI... -5.4
CAPE... +1835.7  CIN... -30.6              | CAPE... +1581.5  CIN... -6.1
                                           |
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 -63.7 -82.7  280  31 16   1.8   1.0 | -64.7 -84.5  300  26 13   0.8   0.4
 45000 -60.3 -76.5  290  31 16   3.4   1.9 | -61.8 -79.2  315  23 12   4.5   2.5
 40000 -54.7 -66.5  310  27 14   6.4   3.5 | -54.6 -66.3  360  22 11   7.2   4.0
 38000 -50.8 -59.4  310  27 14   6.5   3.5 | -50.2 -58.4  350  23 12   7.3   4.0
 36000 -46.4 -51.5  315  27 14   7.6   4.1 | -45.3 -49.5  345  25 13   8.1   4.4
 34000 -41.0 -41.8  315  25 13   9.0   4.9 | -40.0 -40.0  335  26 13   8.9   4.9
 32000 -35.7 -32.3  310  24 12   9.2   5.0 | -34.7 -30.5  325  28 15   9.2   5.0
 30000 -30.7 -23.3  310  23 12   8.2   4.5 | -29.7 -21.5  315  30 15   8.2   4.5
 29000 -28.2 -18.8  310  23 12   8.2   4.5 | -27.3 -17.1  310  31 16   8.2   4.5
 28000 -25.8 -14.4  305  22 11   7.7   4.2 | -24.9 -12.8  305  32 16   7.0   3.9
 27000 -23.5 -10.3  305  22 11   7.7   4.2 | -22.8  -9.0  305  33 17   7.1   3.9
 26000 -21.1  -6.0  305  21 11   7.7   4.2 | -20.7  -5.3  305  34 18   7.1   3.9
 25000 -18.8  -1.8  305  21 11   7.2   4.0 | -18.6  -1.5  300  36 18   7.0   3.8
 24000 -16.9   1.6  300  21 11   6.4   3.5 | -16.5   2.3  300  36 18   6.8   3.7
 23000 -14.9   5.2  300  22 11   6.5   3.5 | -14.5   5.9  300  35 18   6.8   3.7
 22000 -13.0   8.6  295  22 12   6.2   3.4 | -12.4   9.7  300  35 18   6.4   3.5
 21000 -11.3  11.7  295  23 12   5.9   3.2 | -10.7  12.7  295  35 18   6.0   3.3
 20000  -9.6  14.7  295  24 12   6.0   3.3 |  -9.0  15.8  295  34 18   6.1   3.4
 19500  -8.7  16.3  295  24 12   6.1   3.4 |  -8.1  17.4  295  34 18   6.1   3.3
 19000  -7.5  18.5  300  24 12  10.4   5.7 |  -7.0  19.4  290  34 17   9.3   5.1
 18500  -6.1  21.0  300  24 12  10.1   5.6 |  -5.0  23.0  290  33 17   9.1   5.0
 18000  -4.0  24.8  305  23 12   8.9   4.9 |  -3.7  25.3  290  31 16   8.5   4.7
 17500  -2.7  27.1  305  22 12   9.1   5.0 |  -2.5  27.5  290  30 15   8.6   4.7
 17000  -1.4  29.5  310  22 11   9.1   5.0 |  -1.3  29.7  290  28 14   8.4   4.6
 16500  -0.1  31.8  310  20 10   9.1   5.0 |  -0.1  31.8  290  25 13   8.3   4.6
 16000   1.2  34.2  310  19 10   9.0   5.0 |   1.1  34.0  285  23 12   8.2   4.5
 15500   2.5  36.5  310  18  9   8.7   4.8 |   2.2  36.0  285  19 10   7.4   4.1
 15000   3.8  38.8  310  17  9   8.7   4.7 |   3.3  37.9  285  15  8   7.5   4.1
 14500   5.1  41.2  310  15  8   9.2   5.0 |   4.4  39.9  285  11  6   7.4   4.1
 14000   6.4  43.5  310  14  7   9.1   5.0 |   5.4  41.7  290   7  4   7.4   4.1
 13500   7.8  46.0  310  13  7   8.7   4.8 |   6.5  43.7  295   3  2   8.4   4.6
 13000   9.1  48.4  310  11  6   8.6   4.7 |   7.7  45.9  320   1  1   8.8   4.8
 12500  10.3  50.5  310  10  5   8.3   4.6 |   8.9  48.0  070   2  1   9.1   5.0
 12000  11.6  52.9  315   8  4   8.2   4.5 |  10.3  50.5  070   3  1   9.4   5.1
 11500  12.8  55.0  325   7  3   8.1   4.5 |  11.7  53.1  075   3  2   9.4   5.2
 11000  14.0  57.2  335   5  3   7.9   4.3 |  13.1  55.6  070   4  2   9.2   5.0
 10500  15.3  59.5  350   4  2   4.0   2.2 |  14.5  58.1  070   4  2   4.8   2.6
 10250  15.4  59.7  355   4  2   5.3   2.9 |  14.6  58.3  070   4  2   6.4   3.5
 10000  16.1  61.0  010   3  2  11.3   6.2 |  15.5  59.9  070   5  2  13.3   7.3
  9750  16.8  62.2  030   3  2  10.4   5.7 |  16.3  61.3  070   5  2  12.2   6.7
  9500  17.5  63.5  050   3  2   8.1   4.5 |  17.2  63.0  065   5  3   9.8   5.4
  9250  17.9  64.2  055   3  2   6.5   3.6 |  17.8  64.0  065   5  3   7.6   4.2
  9000  18.3  64.9  060   4  2   9.6   5.3 |  18.5  65.3  065   5  3  10.3   5.6
  8750  18.9  66.0  060   4  2  10.5   5.7 |  19.3  66.7  065   5  3  10.8   5.9
  8500  19.5  67.1  065   4  2   9.8   5.4 |  20.0  68.0  065   5  3  10.5   5.8
  8250  20.2  68.4  065   4  2   8.8   4.8 |  20.8  69.4  065   6  3  10.6   5.8
  8000  20.9  69.6  065   4  2  10.1   5.6 |  21.6  70.9  060   6  3  10.0   5.5
  7750  21.7  71.1  060   4  2  11.2   6.1 |  22.3  72.1  060   6  3   9.3   5.1
  7500  22.5  72.5  060   4  2  10.0   5.5 |  23.0  73.4  060   6  3   9.9   5.4
  7250  23.2  73.8  060   3  2   9.6   5.3 |  23.8  74.8  060   6  3  10.2   5.6
  7000  23.9  75.0  060   3  2   9.6   5.3 |  24.5  76.1  060   6  3   9.9   5.5
  6750  24.6  76.3  055   3  2  10.1   5.6 |  25.3  77.5  060   6  3   9.8   5.4
  6500  25.4  77.7  055   3  2  10.9   6.0 |  26.0  78.8  060   6  3  10.2   5.6
  6250  26.3  79.3  055   3  2  11.7   6.4 |  26.8  80.2  055   7  3  10.7   5.9
  6000  27.1  80.8  055   3  2   9.4   5.1 |  27.6  81.7  055   7  3   9.8   5.4
  5750  27.8  82.0  050   3  2  14.3   7.9 |  28.3  82.9  055   7  3  12.1   6.6
  5500  29.4  84.9  050   3  2  29.2  16.0 |  29.4  84.9  055   7  3  18.4  10.1
________________________________________________________________________________

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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