Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 271318
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0618 MST Tuesday, January 27, 2015

This forecast is for Tuesday, January 27, 2015:

If the trigger temperature of 71.9 F/22.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 291 ft/min (1.5 m/s)
   Maximum height of thermals.................. 9399 ft MSL (4114 ft AGL)

Forecast maximum temperature................... 72.0 F/22.7 C
Time of trigger temperature.................... 1330 MST
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................. 6196 ft MSL (910 ft AGL)
Thermal soaring outlook for Wednesday 01/28.... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 14386 ft MSL (9101 ft AGL)
Wave soaring outlook for Wednesday 01/28....... Fair

Remarks... None

Sunrise/Sunset.................... 07:11:41 / 17:11:48 MST
Total possible sunshine........... 10 hr 0 min 7 sec (600 min 7 sec)
Altitude of sun at 12:12:07 MST... 31.90 degrees

Upper air data from rawinsonde observation taken on 01/27/2015 at 0500 MST

Freezing level.................. 13434 ft MSL (8149 ft AGL)
Convective condensation level... 22102 ft MSL (16817 ft AGL)
Lifted condensation level....... 18993 ft MSL (13707 ft AGL)
Lifted index.................... +5.0
K index......................... -7.6

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  -66.2 -87.2   310   26   14   3.0   1.6   87.0 188.6    37.2      M    M
 45000  -59.8 -75.6   270   26   14  -3.3  -1.8   72.2 162.0    30.9      M    M
 40000  -55.7 -68.3   310   29   15   5.2   2.8   55.8 132.4    22.2      M    M
 38000  -58.7 -73.7   280   38   20   1.7   0.9   42.6 108.6    13.8      M    M
 36000  -54.9 -66.8   285   35   18   7.4   4.1   39.4 102.9    12.0      M    M
 34000  -50.6 -59.1   290   31   16   6.9   3.8   37.4  99.2    10.9      M    M
 32000  -45.4 -49.7   280   27   14   8.1   4.5   36.5  97.7    10.5      M    M
 30000  -40.1 -40.2   285   16    8   4.9   2.7   34.8  94.7     9.5      M    M
 29000  -38.6 -37.5   260   12    6   6.3   3.5   32.9  91.3     8.2      M    M
 28000  -35.9 -32.6   265    9    4   9.3   5.1   32.6  90.7     8.0      M    M
 27000  -33.1 -27.6   280    6    3   9.3   5.1   32.5  90.5     8.1      M    M
 26000  -30.4 -22.7   275    9    4   8.9   4.9   32.2  89.9     7.9      M    M
 25000  -27.7 -17.9   275   11    6   8.9   4.9   31.9  89.5     7.8      M    M
 24000  -25.2 -13.4   280   12    6   8.1   4.4   31.4  88.6     7.5      M    M
 23000  -22.6  -8.7   280   14    7   9.6   5.3   31.1  88.0     7.3      M    M
 22000  -19.7  -3.5   285   16    8   9.7   5.3   31.1  87.9     7.3      M    M
 21000  -17.0   1.4   290   14    7   6.4   3.5   30.8  87.4     7.2      M    M
 20000  -15.1   4.8   265   12    6   6.3   3.4   29.5  85.2     6.2      M    M
 19500  -14.2   6.4   255   10    5   6.3   3.4   28.9  84.0     5.7      M    M
 19000  -13.2   8.2   245    9    5   7.2   4.0   28.3  83.0     5.2      M    M
 18500  -12.2  10.0   245    7    4   7.6   4.2   27.8  82.1     4.8      M    M
 18000  -10.8  12.6   240    5    3   9.0   4.9   27.7  81.9     4.7      M    M
 17500   -9.5  14.9   235    3    2   9.1   5.0   27.6  81.7     4.6      M    M
 17000   -8.1  17.4   205    1    1   9.2   5.0   27.5  81.5     4.6      M    M
 16500   -6.8  19.8   245    3    1   7.4   4.1   27.3  81.1     4.4      M    M
 16000   -5.8  21.6   255    5    3   7.2   3.9   26.9  80.4     4.1      M    M
 15500   -4.7  23.5   270    7    4   7.1   3.9   26.5  79.6     3.7      M    M
 15000   -3.1  26.4   280   10    5   7.2   3.9   25.8  78.5     3.1      M    M
 14500   -2.1  28.2   270   10    5   7.2   3.9   25.4  77.7     2.8      M    M
 14000   -1.0  30.2   255   11    6   7.2   3.9   25.0  77.0     2.4      M    M
 13500    0.1  32.2   240   12    6   7.2   3.9   24.5  76.1     1.9      M    M
 13000    1.1  34.0   225   14    7   7.2   4.0   24.1  75.4     1.5      M    M
 12500    2.2  36.0   215   16    8   7.8   4.3   23.7  74.6     1.2      M    M
 12000    3.4  38.1   210   18    9   8.3   4.6   23.5  74.2     0.9      M    M
 11500    4.7  40.5   225   17    9   8.3   4.6   23.2  73.8     0.7      M    M
 11000    5.9  42.6   235   17    9   8.4   4.6   23.0  73.4     0.5      M    M
 10500    7.1  44.8   225   19   10   8.5   4.6   22.8  73.0     0.3      M    M
 10250    7.8  46.0   225   19   10   8.8   4.8   22.7  72.9     0.2      M    M
 10000    8.4  47.1   225   18    9   8.8   4.9   22.7  72.8     0.2      M    M
  9750    9.1  48.4   225   18    9   8.8   4.8   22.6  72.7     0.1      M    M
  9500    9.8  49.6   225   19   10   8.8   4.8   22.5  72.5     0.0      M    M
  9250   10.4  50.7   225   19   10   8.8   4.8   22.5  72.4    -0.0    271  1.4
  9000   11.1  52.0   225   19   10   8.8   4.8   22.4  72.3    -0.1    244  1.2
  8750   11.7  53.1   225   18   10   8.8   4.8   22.3  72.2    -0.2    217  1.1
  8500   12.4  54.3   225   18    9   8.8   4.8   22.3  72.1    -0.3    190  1.0
  8250   13.0  55.4   225   17    9   8.8   4.8   22.2  71.9    -0.3    163  0.8
  8000   13.7  56.7   225   17    9   8.8   4.8   22.1  71.8    -0.4    136  0.7
  7750   14.4  57.9   225   17    9   8.8   4.8   22.1  71.7    -0.5    109  0.6
  7500   15.0  59.0   230   17    9   8.8   4.8   22.0  71.6    -0.5     82  0.4
  7250   15.7  60.3   230   17    9   8.9   4.9   21.9  71.4    -0.6     55  0.3
  7000   16.3  61.3   230   17    9   8.7   4.8   21.8  71.3    -0.7     28  0.1
  6750   17.0  62.6   225   18    9   9.2   5.1   21.8  71.2    -0.8      0  0.0
  6500   17.6  63.7   220   20   10   6.3   3.5   21.7  71.0    -0.9      M    M
  6250   17.2  63.0   220   21   11 -24.1 -13.2   20.5  69.0    -2.0      M    M
  6000   14.7  58.5   215   23   12 -22.6 -12.4   17.3  63.2    -5.3     46  0.2
  5750   14.0  57.2   215   18    9 -12.9  -7.1   15.9  60.6    -6.7     61  0.3
  5500   11.3  52.3   210   13    7 -60.9 -33.4   12.5  54.5   -10.2    134  0.7

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

           01/27/2015 at 0800 MST          |       01/27/2015 at 1100 MST
                                           |
K index... +5.5  LI... +4.5                | K index... +3.8  LI... +4.6
CAPE... 0.0  CIN... -0.8                   | CAPE... 0.0  CIN... -0.8
                                           |
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 -64.0 -83.2  300  31 16   5.1   2.8 | -63.8 -82.8  295  31 16   4.7   2.6
 45000 -57.2 -71.0  275  32 17  -0.7  -0.4 | -57.2 -71.0  280  36 19   0.8   0.5
 40000 -58.2 -72.8  280  33 17  -1.0  -0.6 | -55.9 -68.6  280  39 20   0.8   0.4
 38000 -56.1 -69.0  280  29 15   4.5   2.5 | -54.6 -66.3  275  32 16   2.5   1.4
 36000 -53.4 -64.1  280  25 13   4.5   2.5 | -53.1 -63.6  260  24 12   2.5   1.4
 34000 -49.8 -57.6  280  21 11   7.6   4.2 | -50.0 -58.0  250  21 11   8.3   4.5
 32000 -45.2 -49.4  280  19 10   7.6   4.2 | -44.4 -47.9  240  22 11   8.3   4.5
 30000 -40.0 -40.0  270  17  9   7.8   4.3 | -39.7 -39.5  235  22 11   7.7   4.2
 29000 -37.7 -35.9  260  17  9   7.8   4.3 | -37.4 -35.3  235  22 11   7.6   4.2
 28000 -35.4 -31.7  255  17  9   7.8   4.3 | -35.1 -31.2  230  22 11   7.6   4.2
 27000 -33.0 -27.4  255  16  8   8.1   4.5 | -32.8 -27.0  230  21 11   7.8   4.3
 26000 -30.5 -22.9  255  15  7   8.1   4.5 | -30.4 -22.7  235  20 10   7.8   4.3
 25000 -28.1 -18.6  260  13  7   8.2   4.5 | -28.1 -18.6  235  19 10   7.9   4.3
 24000 -25.5 -13.9  260  13  6   9.2   5.0 | -25.6 -14.1  240  18  9   9.1   5.0
 23000 -22.7  -8.9  260  13  6   9.2   5.1 | -22.8  -9.0  235  17  9   9.1   5.0
 22000 -20.0  -4.0  260  13  6   9.3   5.1 | -20.1  -4.2  235  15  8   9.2   5.0
 21000 -17.5   0.5  255  12  6   7.9   4.4 | -17.5   0.5  230  15  8   8.2   4.5
 20000 -15.1   4.8  235  12  6   7.9   4.4 | -15.1   4.8  230  15  8   8.2   4.5
 19500 -13.9   7.0  230  12  6   7.9   4.4 | -13.8   7.2  230  15  8   8.2   4.5
 19000 -12.7   9.1  220  12  6   7.8   4.3 | -12.6   9.3  230  15  8   7.8   4.3
 18500 -11.6  11.1  215  11  6   7.6   4.2 | -11.5  11.3  230  15  8   7.2   3.9
 18000 -10.5  13.1  210  11  5   7.6   4.2 | -10.5  13.1  230  14  7   7.3   4.0
 17500  -9.4  15.1  210  10  5   7.1   3.9 |  -9.5  14.9  230  14  7   6.3   3.5
 17000  -8.3  17.1  210   9  5   7.1   3.9 |  -8.5  16.7  230  13  7   6.3   3.5
 16500  -7.3  18.9  205   9  5   6.6   3.6 |  -7.6  18.3  230  12  6   6.5   3.6
 16000  -6.4  20.5  210   8  4   6.2   3.4 |  -6.2  20.8  230  10  5   6.6   3.6
 15500  -5.5  22.1  210   7  4   6.3   3.5 |  -5.1  22.8  230  10  5   7.4   4.1
 15000  -4.0  24.8  225   7  3   6.9   3.8 |  -4.0  24.8  225   9  5   7.7   4.2
 14500  -3.0  26.6  235   7  3   7.5   4.1 |  -2.9  26.8  225   9  5   8.1   4.4
 14000  -1.8  28.8  240   7  4   8.2   4.5 |  -1.6  29.1  225   9  5   8.5   4.7
 13500  -0.5  31.1  245   8  4   8.5   4.6 |  -0.3  31.5  225   9  5   8.6   4.7
 13000   0.8  33.4  245   9  5   9.0   5.0 |   0.9  33.6  230   9  5   8.6   4.7
 12500   2.1  35.8  245  11  6   9.0   4.9 |   2.2  36.0  230   9  5   8.6   4.7
 12000   3.5  38.3  245  12  6   8.9   4.9 |   3.5  38.3  235   9  5   8.9   4.9
 11500   4.8  40.6  245  14  7   8.9   4.9 |   4.9  40.8  240   9  5   8.8   4.9
 11000   6.1  43.0  245  14  7   8.5   4.6 |   6.1  43.0  240  10  5   7.9   4.3
 10500   7.4  45.3  240  15  8   6.3   3.5 |   7.3  45.1  240  10  5   6.5   3.6
 10250   7.7  45.9  240  15  8   4.8   2.6 |   7.7  45.9  240  10  5   4.7   2.6
 10000   8.2  46.8  240  15  8   9.6   5.3 |   8.1  46.6  240   9  5   8.0   4.4
  9750   9.1  48.4  240  15  8  11.7   6.4 |   8.8  47.8  240   9  4   9.9   5.4
  9500   9.9  49.8  240  15  7  10.2   5.6 |   9.5  49.1  240   8  4   8.7   4.8
  9250  10.5  50.9  240  14  7   7.7   4.2 |  10.1  50.2  235   8  4   6.6   3.6
  9000  11.1  52.0  240  14  7   8.3   4.6 |  10.6  51.1  235   7  4   7.3   4.0
  8750  11.8  53.2  240  13  7  10.0   5.5 |  11.2  52.2  230   6  3   9.0   4.9
  8500  12.5  54.5  240  12  6   9.0   4.9 |  11.8  53.2  230   6  3   8.1   4.4
  8250  13.2  55.8  240  12  6   8.3   4.5 |  12.4  54.3  225   5  3   7.4   4.1
  8000  13.8  56.8  240  11  6   8.2   4.5 |  12.9  55.2  220   5  2   7.5   4.1
  7750  14.4  57.9  240  10  5   8.5   4.7 |  13.5  56.3  210   4  2   8.3   4.6
  7500  15.0  59.0  245   9  5   7.3   4.0 |  14.1  57.4  205   4  2   6.6   3.6
  7250  15.5  59.9  245   8  4   5.5   3.0 |  14.5  58.1  205   3  2   4.6   2.5
  7000  15.9  60.6  250   8  4   7.6   4.2 |  14.9  58.8  205   2  1   6.1   3.3
  6750  16.4  61.5  255   7  4   1.2   0.6 |  15.3  59.5  205   2  1   3.2   1.8
  6500  15.9  60.6  255   7  4 -12.2  -6.7 |  15.2  59.4  210   2  1  -4.8  -2.6
  6250  14.5  58.1  250   8  4 -26.7 -14.7 |  14.6  58.3  225   2  1  -9.6  -5.2
  6000  13.1  55.6  250   9  5   7.5   4.1 |  14.0  57.2  230   3  2  -3.3  -1.8
  5750  14.1  57.4  255  11  6 -18.6 -10.2 |  13.8  56.8  245   6  3  -6.2  -3.4
  5500   7.4  45.3  235   8  4 -99.0 -54.3 |  12.5  54.5  225   5  3 -25.8 -14.2

           01/27/2015 at 1400 MST          |       01/27/2015 at 1700 MST
                                           |
K index... +2.3  LI... +3.8                | K index... -0.1  LI... +2.7
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.8 -82.8  290  33 17   4.2   2.3 | -64.7 -84.5  285  34 17   3.9   2.1
 45000 -57.8 -72.0  280  42 22   2.6   1.4 | -58.7 -73.7  280  44 23   3.4   1.9
 40000 -53.9 -65.0  275  47 24   2.7   1.5 | -53.5 -64.3  280  44 23   3.5   1.9
 38000 -53.0 -63.4  270  40 20   1.3   0.7 | -52.5 -62.5  275  43 22   1.4   0.7
 36000 -52.2 -62.0  265  31 16   1.3   0.7 | -51.6 -60.9  270  41 21   1.4   0.8
 34000 -49.8 -57.6  250  27 14   7.7   4.2 | -49.2 -56.6  270  40 20   7.9   4.3
 32000 -44.6 -48.3  240  30 15   7.7   4.2 | -43.9 -47.0  265  38 19   7.8   4.3
 30000 -39.8 -39.6  235  31 16   8.2   4.5 | -39.2 -38.6  260  36 18   7.8   4.3
 29000 -37.4 -35.3  230  31 16   8.2   4.5 | -36.8 -34.2  255  34 18   7.8   4.3
 28000 -34.9 -30.8  225  31 16   8.2   4.5 | -34.5 -30.1  250  34 17   7.9   4.3
 27000 -32.6 -26.7  220  30 15   7.7   4.2 | -32.1 -25.8  245  33 17   8.3   4.5
 26000 -30.3 -22.5  220  28 14   7.6   4.2 | -29.6 -21.3  240  33 17   8.3   4.6
 25000 -28.0 -18.4  220  26 13   7.7   4.2 | -27.1 -16.8  230  33 17   8.3   4.6
 24000 -25.6 -14.1  220  25 13   8.5   4.7 | -24.8 -12.6  225  33 17   6.9   3.8
 23000 -23.0  -9.4  215  23 12   8.5   4.7 | -22.6  -8.7  225  31 16   7.0   3.9
 22000 -20.4  -4.7  215  22 11   8.5   4.7 | -20.5  -4.9  220  30 16   7.1   3.9
 21000 -18.0  -0.4  215  21 11   7.6   4.2 | -18.3  -0.9  220  29 15   7.8   4.3
 20000 -15.8   3.6  215  20 11   7.6   4.2 | -16.0   3.2  215  28 14   7.8   4.3
 19500 -14.6   5.7  215  20 10   7.6   4.2 | -14.8   5.4  215  27 14   7.8   4.3
 19000 -13.5   7.7  210  20 10   7.4   4.1 | -13.6   7.5  215  26 13   7.7   4.2
 18500 -12.5   9.5  210  19 10   6.8   3.7 | -12.6   9.3  215  25 13   6.9   3.8
 18000 -11.4  11.5  210  19 10   6.8   3.7 | -11.5  11.3  215  23 12   6.9   3.8
 17500 -10.4  13.3  210  18  9   7.2   4.0 | -10.5  13.1  215  22 11   7.3   4.0
 17000  -9.3  15.3  210  17  9   7.3   4.0 |  -9.4  15.1  210  21 11   7.4   4.0
 16500  -8.3  17.1  210  16  8   7.5   4.1 |  -8.3  17.1  210  20 10   7.4   4.1
 16000  -6.5  20.3  215  15  8   7.9   4.3 |  -6.6  20.1  210  18  9   7.5   4.1
 15500  -5.3  22.5  215  14  7   8.2   4.5 |  -5.5  22.1  210  17  9   7.9   4.3
 15000  -4.1  24.6  215  14  7   8.4   4.6 |  -4.2  24.4  205  16  8   8.2   4.5
 14500  -2.8  27.0  215  13  7   8.5   4.6 |  -3.0  26.6  205  15  8   8.1   4.5
 14000  -1.5  29.3  220  13  7   8.5   4.7 |  -1.8  28.8  205  14  7   8.0   4.4
 13500  -0.3  31.5  220  12  6   8.5   4.6 |  -0.6  30.9  205  13  7   8.0   4.4
 13000   1.0  33.8  220  12  6   8.0   4.4 |   0.5  32.9  205  12  6   7.1   3.9
 12500   2.1  35.8  225  11  6   8.1   4.4 |   1.5  34.7  205  10  5   7.2   4.0
 12000   3.3  37.9  225  10  5   7.9   4.3 |   2.6  36.7  205   8  4   7.1   3.9
 11500   4.5  40.1  230   9  4   7.9   4.3 |   3.6  38.5  200   6  3   7.1   3.9
 11000   5.6  42.1  235   7  4   7.6   4.2 |   4.7  40.5  200   4  2   7.0   3.9
 10500   6.8  44.2  235   6  3   6.7   3.7 |   5.7  42.3  210   1  1   7.5   4.1
 10250   7.2  45.0  240   6  3   4.9   2.7 |   6.2  43.2  245   1  0   4.2   2.3
 10000   7.6  45.7  240   6  3   7.8   4.3 |   6.4  43.5  300   1  0   5.0   2.8
  9750   8.3  46.9  240   5  3  10.1   5.5 |   7.0  44.6  350   1  1   8.6   4.7
  9500   9.0  48.2  240   5  3   9.1   5.0 |   7.6  45.7  360   3  1   7.7   4.2
  9250   9.6  49.3  240   5  2   6.8   3.7 |   8.1  46.6  360   4  2   7.2   3.9
  9000  10.1  50.2  240   4  2   6.9   3.8 |   8.6  47.5  355   5  2   7.5   4.1
  8750  10.7  51.3  245   4  2   8.5   4.7 |   9.3  48.7  350   6  3   8.4   4.6
  8500  11.3  52.3  245   3  2   7.5   4.1 |   9.9  49.8  350   6  3   8.2   4.5
  8250  11.8  53.2  250   3  2   6.5   3.6 |  10.5  50.9  340   8  4   8.7   4.8
  8000  12.3  54.1  260   2  1   6.2   3.4 |  11.2  52.2  330   9  5   8.6   4.7
  7750  12.7  54.9  280   2  1   6.4   3.5 |  11.8  53.2  320  11  6   8.5   4.6
  7500  13.2  55.8  305   2  1   5.9   3.3 |  12.4  54.3  315  13  7   7.3   4.0
  7250  13.6  56.5  320   2  1   5.5   3.0 |  12.8  55.0  310  14  7   5.9   3.2
  7000  14.0  57.2  330   3  2   5.6   3.0 |  13.2  55.8  310  15  8   5.8   3.2
  6750  14.4  57.9  340   4  2   4.8   2.6 |  13.6  56.5  310  16  8   4.6   2.5
  6500  14.7  58.5  340   4  2   3.6   2.0 |  13.8  56.8  310  15  8   3.9   2.1
  6250  14.9  58.8  325   3  2   4.1   2.2 |  14.0  57.2  310  12  6   3.3   1.8
  6000  15.1  59.2  305   3  1   2.4   1.3 |  14.2  57.6  310  10  5   5.9   3.3
  5750  15.1  59.2  260   2  1   5.3   2.9 |  14.5  58.1  310   7  4   1.4   0.8
  5500  15.8  60.4  245   2  1  15.6   8.6 |  13.9  57.0  290   4  2 -15.4  -8.5
________________________________________________________________________________

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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