Soaring Guidance
Issued by NWS Denver/Boulder, CO

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UXUS97 KBOU 200125
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Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1924 MDT Thursday, October 19, 2017

This forecast is for Friday, October 20, 2017:

If the trigger temperature of 72.7 F/22.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 849 ft/min (4.3 m/s)
   Maximum height of thermals.................. 16718 ft MSL (11411 ft AGL)

Forecast maximum temperature................... 80.0 F/27.1 C
Time of trigger temperature.................... 1145 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................. 10878 ft MSL (5571 ft AGL)
Thermal soaring outlook for Saturday 10/21..... Good

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....................... 35292 ft MSL (29985 ft AGL)
Wave soaring outlook for Saturday 10/21........ Fair

Remarks...

Sunrise/Sunset.................... 07:15:25 / 18:13:58 MDT
Total possible sunshine........... 10 hr 58 min 33 sec (658 min 33 sec)
Altitude of sun at 12:44:16 MDT... 39.65 degrees

Upper air data from numerical model forecast valid on 10/20/2017 at 0600 MDT

Freezing level.................. 13650 ft MSL (8343 ft AGL)
Convective condensation level... 17489 ft MSL (12182 ft AGL)
Lifted condensation level....... 17203 ft MSL (11897 ft AGL)
Lifted index.................... +0.9
K index......................... +15.4

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  -62.1 -79.8   240   25   13   0.9   0.5      M     M       M      M    M
 45000  -60.4 -76.7   235   23   12   2.4   1.3      M     M       M      M    M
 40000  -56.9 -70.4   230   23   12   2.3   1.3      M     M       M      M    M
 38000  -54.7 -66.5   225   26   13   3.9   2.1      M     M       M      M    M
 36000  -52.4 -62.3   225   30   16   3.9   2.1      M     M       M      M    M
 34000  -48.8 -55.8   220   31   16   8.9   4.9      M     M       M      M    M
 32000  -43.4 -46.1   210   29   15   8.9   4.9      M     M       M      M    M
 30000  -37.5 -35.5   210   26   13   8.6   4.7   37.5  99.5     8.2      M    M
 29000  -34.9 -30.8   210   24   12   8.6   4.7   37.1  98.7     8.0      M    M
 28000  -32.4 -26.3   215   22   11   8.6   4.7   36.7  98.1     7.8      M    M
 27000  -29.8 -21.6   220   21   11   8.4   4.6   36.2  97.2     7.5      M    M
 26000  -27.3 -17.1   220   22   11   8.4   4.6   35.7  96.2     7.1      M    M
 25000  -24.8 -12.6   215   22   11   8.4   4.6   35.2  95.4     6.9      M    M
 24000  -22.4  -8.3   215   22   12   7.2   3.9   34.7  94.4     6.5      M    M
 23000  -20.2  -4.4   210   23   12   7.3   4.0   33.7  92.7     5.7      M    M
 22000  -18.0  -0.4   210   23   12   7.4   4.0   32.9  91.2     5.1      M    M
 21000  -15.9   3.4   210   23   12   6.8   3.7   32.0  89.6     4.3      M    M
 20000  -13.9   7.0   210   23   12   6.8   3.8   30.9  87.6     3.4      M    M
 19500  -12.9   8.8   210   22   11   6.9   3.8   30.4  86.7     3.0      M    M
 19000  -11.9  10.6   210   22   11   6.9   3.8   30.0  85.9     2.6      M    M
 18500  -10.9  12.4   210   21   11   6.0   3.3   29.4  85.0     2.2      M    M
 18000  -10.0  14.0   210   19   10   6.0   3.3   28.8  83.8     1.6      M    M
 17500   -9.1  15.6   215   17    9   5.9   3.2   28.1  82.6     1.1      M    M
 17000   -8.2  17.2   215   15    8   5.7   3.1   27.4  81.4     0.5      M    M
 16500   -7.4  18.7   220   14    7   5.5   3.0   26.8  80.2    -0.1   1041  5.3
 16000   -6.4  20.5   220   13    7   8.2   4.5   26.3  79.3    -0.6    997  5.1
 15500   -4.7  23.5   220   12    6   8.2   4.5   25.9  78.5    -1.1    923  4.7
 15000   -3.4  25.9   220   11    6   9.3   5.1   25.7  78.2    -1.3    870  4.4
 14500   -2.1  28.2   220   11    5   9.3   5.1   25.6  78.1    -1.4    815  4.1
 14000   -0.7  30.7   220   10    5   9.2   5.1   25.5  77.9    -1.5    760  3.9
 13500    0.6  33.1   220    9    5   9.3   5.1   25.4  77.8    -1.6    704  3.6
 13000    2.0  35.6   220    8    4   8.5   4.7   25.3  77.6    -1.8    649  3.3
 12500    3.2  37.8   225    7    3   8.3   4.6   25.1  77.2    -2.0    598  3.0
 12000    4.4  39.9   230    6    3   7.9   4.3   24.9  76.8    -2.2    546  2.8
 11500    5.6  42.1   250    4    2   7.6   4.2   24.5  76.1    -2.6    497  2.5
 11000    6.7  44.1   280    3    2   7.3   4.0   24.2  75.5    -2.9    449  2.3
 10500    7.7  45.9   310    4    2   6.6   3.6   23.7  74.7    -3.4    403  2.0
 10250    8.3  46.9   320    5    3   8.6   4.7   23.5  74.4    -3.6    380  1.9
 10000    9.0  48.2   325    6    3   9.6   5.3   23.5  74.4    -3.6    351  1.8
  9750    9.6  49.3   325    7    4   8.3   4.5   23.4  74.2    -3.7    325  1.6
  9500   10.2  50.4   325    8    4   8.7   4.8   23.4  74.0    -3.8    298  1.5
  9250   10.9  51.6   325    9    5   8.5   4.7   23.3  73.9    -3.9    272  1.4
  9000   11.5  52.7   325   10    5   8.5   4.7   23.2  73.7    -4.0    246  1.2
  8750   12.1  53.8   325   11    6   8.5   4.7   23.1  73.5    -4.2    220  1.1
  8500   12.7  54.9   320   12    6   8.5   4.6   23.0  73.4    -4.3    194  1.0
  8250   13.4  56.1   320   13    7   8.7   4.8   22.9  73.2    -4.4    168  0.9
  8000   14.0  57.2   320   13    7   8.0   4.4   22.8  73.0    -4.5    141  0.7
  7750   14.6  58.3   320   13    7   6.9   3.8   22.6  72.7    -4.6    116  0.6
  7500   15.1  59.2   320   13    7   7.1   3.9   22.4  72.3    -4.9     94  0.5
  7250   15.6  60.1   320   13    7   6.3   3.5   22.2  71.9    -5.1     71  0.4
  7000   16.0  60.8   320   12    6   4.9   2.7   21.9  71.3    -5.4     51  0.3
  6750   16.4  61.5   320   11    6   2.7   1.5   21.4  70.5    -5.8     34  0.2
  6500   16.5  61.7   320   10    5   3.3   1.8   20.8  69.5    -6.4     21  0.1
  6250   16.6  61.9   320    9    5  -6.7  -3.7   20.2  68.3    -7.1     12  0.1
  6000   15.6  60.1   310    7    4 -15.1  -8.3   18.4  65.1    -8.9     36  0.2
  5750   14.4  57.9   290    6    3 -19.0 -10.4   16.5  61.8   -10.8     63  0.3
  5500   12.0  53.6   245    7    4 -46.6 -25.6   13.5  56.3   -14.0    128  0.7

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

           10/20/2017 at 0900 MDT          |       10/20/2017 at 1200 MDT
                                           |
K index... +20.9  LI... +1.2               | K index... +21.1  LI... -0.1
CAPE... 0.0  CIN... 0.0                    | CAPE... +4.1  CIN... -23.4
                                           |
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 -61.6 -78.9  240  25 13   0.2   0.1 | -61.4 -78.5  235  31 16   0.8   0.4
 45000 -60.9 -77.6  240  22 12   3.2   1.7 | -60.1 -76.2  245  32 17   1.6   0.9
 40000 -56.1 -69.0  265  23 12   3.0   1.6 | -57.6 -71.7  280  27 14   1.3   0.7
 38000 -53.5 -64.3  255  23 12   4.6   2.5 | -53.9 -65.0  280  28 14   7.4   4.1
 36000 -50.7 -59.3  235  24 12   4.6   2.5 | -49.4 -56.9  280  29 15   7.4   4.1
 34000 -47.5 -53.5  225  27 14   6.8   3.7 | -45.3 -49.5  275  27 14   6.3   3.5
 32000 -43.4 -46.1  215  32 16   6.8   3.7 | -41.5 -42.7  250  26 13   6.3   3.5
 30000 -38.2 -36.8  210  33 17   9.1   5.0 | -37.5 -35.5  230  29 15   7.0   3.8
 29000 -35.4 -31.7  210  31 16   9.1   5.0 | -34.9 -30.8  220  32 17   7.0   3.8
 28000 -32.7 -26.9  210  29 15   9.1   5.0 | -32.9 -27.2  210  36 18   7.0   3.9
 27000 -30.1 -22.2  210  27 14   8.4   4.6 | -30.6 -23.1  210  38 19   8.3   4.5
 26000 -27.6 -17.7  210  26 13   8.4   4.6 | -28.2 -18.8  210  37 19   8.2   4.5
 25000 -25.0 -13.0  210  25 13   8.5   4.6 | -25.7 -14.3  215  36 19   8.2   4.5
 24000 -22.6  -8.7  210  24 12   6.9   3.8 | -23.3  -9.9  220  35 18   7.7   4.2
 23000 -20.6  -5.1  215  24 12   7.0   3.8 | -21.0  -5.8  225  33 17   7.7   4.2
 22000 -18.5  -1.3  220  25 13   7.0   3.8 | -18.7  -1.7  230  31 16   7.7   4.2
 21000 -16.5   2.3  225  25 13   6.5   3.6 | -16.6   2.1  230  29 15   5.2   2.9
 20000 -14.5   5.9  230  24 12   6.6   3.6 | -15.0   5.0  230  26 14   5.6   3.1
 19500 -13.5   7.7  230  23 12   6.6   3.6 | -14.2   6.4  230  25 13   5.6   3.1
 19000 -12.6   9.3  230  23 12   6.6   3.6 | -13.3   8.1  230  24 12   5.6   3.1
 18500 -11.6  11.1  230  23 12   6.2   3.4 | -12.5   9.5  235  22 12   6.2   3.4
 18000 -10.7  12.7  230  22 11   6.1   3.4 | -11.6  11.1  235  21 11   6.4   3.5
 17500  -9.9  14.2  230  22 11   6.3   3.4 | -10.7  12.7  235  20 10   6.5   3.6
 17000  -8.9  16.0  230  21 11   6.9   3.8 |  -9.6  14.7  240  18  9   7.4   4.1
 16500  -7.9  17.8  230  20 10   6.9   3.8 |  -8.6  16.5  245  17  9   7.3   4.0
 16000  -6.9  19.6  230  19 10   7.6   4.2 |  -7.5  18.5  250  16  8   7.7   4.2
 15500  -5.2  22.6  230  18  9   7.7   4.2 |  -6.3  20.7  255  15  8   7.8   4.3
 15000  -4.0  24.8  230  17  9   8.3   4.6 |  -4.6  23.7  260  14  7   8.2   4.5
 14500  -2.8  27.0  230  15  8   8.3   4.6 |  -3.4  25.9  260  14  7   8.2   4.5
 14000  -1.6  29.1  230  14  7   7.9   4.3 |  -2.2  28.0  265  13  7   8.4   4.6
 13500  -0.5  31.1  230  12  6   7.8   4.3 |  -1.0  30.2  265  13  7   8.4   4.6
 13000   0.7  33.3  235  11  6   8.0   4.4 |   0.3  32.5  265  13  7   8.5   4.7
 12500   1.9  35.4  235  10  5   8.1   4.4 |   1.6  34.9  265  13  7   8.6   4.7
 12000   3.1  37.6  235   9  5   8.6   4.7 |   2.8  37.0  265  14  7   8.9   4.9
 11500   4.4  39.9  240   9  5   9.2   5.0 |   4.2  39.6  270  16  8   9.2   5.1
 11000   5.8  42.4  240   9  5   8.7   4.8 |   5.6  42.1  275  17  9   8.9   4.9
 10500   7.0  44.6  245  11  5   7.7   4.2 |   6.7  44.1  275  18  9   7.9   4.3
 10250   7.6  45.7  245  11  6   9.5   5.2 |   7.3  45.1  275  18  9   8.8   4.8
 10000   8.4  47.1  250  12  6  10.1   5.5 |   8.0  46.4  275  17  9   9.0   4.9
  9750   9.0  48.2  250  12  6   8.4   4.6 |   8.6  47.5  275  16  8   7.9   4.3
  9500   9.7  49.5  250  12  6   9.0   5.0 |   9.1  48.4  275  16  8   8.4   4.6
  9250  10.3  50.5  250  13  6   7.9   4.3 |   9.7  49.5  275  17  9   6.5   3.6
  9000  10.8  51.4  255  13  7   7.2   4.0 |  10.1  50.2  275  17  9   6.3   3.5
  8750  11.4  52.5  255  13  7   7.9   4.3 |  10.7  51.3  270  16  8   8.8   4.9
  8500  12.0  53.6  255  13  6   7.4   4.1 |  11.4  52.5  270  15  8   8.8   4.8
  8250  12.6  54.7  255  12  6   8.7   4.7 |  12.0  53.6  270  14  7   9.3   5.1
  8000  13.3  55.9  260  12  6   9.8   5.4 |  12.7  54.9  270  13  7  10.0   5.5
  7750  14.0  57.2  265  13  7   7.8   4.3 |  13.4  56.1  265  12  6   8.7   4.8
  7500  14.5  58.1  265  13  7   6.7   3.7 |  14.0  57.2  265  11  6   7.5   4.1
  7250  15.0  59.0  270  13  7   6.8   3.7 |  14.6  58.3  265  10  5   8.1   4.5
  7000  15.5  59.9  270  13  7   6.0   3.3 |  15.2  59.4  265   9  4   9.1   5.0
  6750  15.9  60.6  270  12  6   4.1   2.2 |  15.9  60.6  265   8  4   9.4   5.2
  6500  16.2  61.2  270  11  5   5.8   3.2 |  16.6  61.9  265   7  4   8.9   4.9
  6250  16.5  61.7  270   9  5  -2.8  -1.6 |  17.3  63.1  260   6  3   9.6   5.3
  6000  15.8  60.4  260   9  5 -10.9  -6.0 |  18.1  64.6  260   6  3  10.5   5.8
  5750  14.9  58.8  255   9  4 -17.5  -9.6 |  18.9  66.0  260   6  3  11.1   6.1
  5500  12.8  55.0  235   8  4 -34.9 -19.1 |  19.8  67.6  265   5  3  15.6   8.5

           10/20/2017 at 1500 MDT          |       10/20/2017 at 1800 MDT
                                           |
K index... +12.9  LI... +0.8               | K index... +21.1  LI... -0.9
CAPE... +2.0  CIN... -13.9                 | CAPE... +37.7  CIN... -19.1
                                           |
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 -61.2 -78.2  240  43 22   0.6   0.3 | -59.3 -74.7  240  39 20   1.7   1.0
 45000 -60.2 -76.4  240  48 25   1.8   1.0 | -56.9 -70.4  245  48 25  -0.7  -0.4
 40000 -57.6 -71.7  225  39 20   1.8   1.0 | -57.6 -71.7  230  50 26  -0.5  -0.3
 38000 -54.7 -66.5  230  40 21   6.2   3.4 | -55.6 -68.1  235  50 26   5.4   3.0
 36000 -50.5 -58.9  240  45 23   6.2   3.4 | -52.4 -62.3  240  50 26   5.4   3.0
 34000 -46.5 -51.7  245  46 24   7.2   4.0 | -48.2 -54.8  250  52 27   7.5   4.1
 32000 -42.1 -43.8  250  44 23   7.2   3.9 | -43.7 -46.7  250  54 28   7.5   4.1
 30000 -37.7 -35.9  250  42 22   7.7   4.2 | -39.1 -38.4  250  54 28   8.0   4.4
 29000 -35.4 -31.7  250  40 20   7.7   4.2 | -36.7 -34.1  250  51 26   8.0   4.4
 28000 -33.1 -27.6  250  37 19   7.7   4.2 | -34.3 -29.7  250  48 25   8.0   4.4
 27000 -30.7 -23.3  250  36 18   8.4   4.6 | -31.8 -25.2  250  46 23   8.8   4.9
 26000 -28.2 -18.8  255  35 18   8.3   4.6 | -29.2 -20.6  250  44 23   8.9   4.9
 25000 -25.7 -14.3  255  34 18   8.3   4.6 | -26.5 -15.7  255  42 22   8.9   4.9
 24000 -23.2  -9.8  260  34 17   7.2   4.0 | -23.9 -11.0  255  41 21   8.3   4.6
 23000 -21.3  -6.3  255  32 16   6.5   3.5 | -21.5  -6.7  240  36 18   7.8   4.3
 22000 -19.3  -2.7  245  30 16   6.5   3.5 | -19.2  -2.6  230  32 17   7.8   4.3
 21000 -17.3   0.9  240  29 15   7.5   4.1 | -17.0   1.4  215  31 16   5.3   2.9
 20000 -15.0   5.0  245  27 14   7.7   4.2 | -15.7   3.7  220  30 16   4.4   2.4
 19500 -13.9   7.0  245  26 13   7.8   4.3 | -15.0   5.0  225  30 15   4.5   2.4
 19000 -12.7   9.1  245  25 13   7.8   4.3 | -14.4   6.1  230  30 15   4.5   2.5
 18500 -10.9  12.4  250  24 13   9.0   4.9 | -13.7   7.3  230  29 15   5.2   2.8
 18000  -9.6  14.7  250  26 13   8.9   4.9 | -12.9   8.8  240  29 15   6.3   3.4
 17500  -8.2  17.2  255  27 14   8.1   4.4 | -12.0  10.4  245  29 15   6.3   3.5
 17000  -7.2  19.0  255  29 15   7.2   3.9 | -10.6  12.9  250  29 15   6.8   3.7
 16500  -6.1  21.0  255  30 16   7.2   3.9 |  -9.6  14.7  255  28 14   6.6   3.6
 16000  -5.2  22.6  255  31 16   5.9   3.2 |  -8.4  16.9  255  27 14  10.0   5.5
 15500  -4.3  24.3  255  31 16   6.1   3.3 |  -7.0  19.4  255  25 13   9.7   5.3
 15000  -3.5  25.7  255  30 16   6.0   3.3 |  -5.5  22.1  250  24 12   9.6   5.3
 14500  -2.7  27.1  255  28 14   6.1   3.4 |  -4.1  24.6  250  23 12   9.6   5.3
 14000  -1.9  28.6  255  25 13   6.5   3.6 |  -2.7  27.1  250  22 11   9.7   5.3
 13500  -0.9  30.4  250  22 12   6.8   3.7 |  -1.2  29.8  250  21 11   9.8   5.4
 13000  -0.0  32.0  240  20 10   7.5   4.1 |   0.3  32.5  255  20 10   9.8   5.4
 12500   1.3  34.3  235  18  9   9.3   5.1 |   1.7  35.1  255  18  9   9.9   5.4
 12000   2.6  36.7  230  17  9   9.2   5.1 |   3.2  37.8  255  17  9   9.8   5.4
 11500   4.0  39.2  225  16  8   9.2   5.0 |   4.6  40.3  255  15  8   9.1   5.0
 11000   5.4  41.7  220  15  8   9.2   5.0 |   6.0  42.8  260  14  7   9.2   5.1
 10500   6.8  44.2  215  14  7   9.2   5.1 |   7.4  45.3  260  12  6   9.6   5.3
 10250   7.4  45.3  215  13  7   9.0   4.9 |   8.1  46.6  260  12  6   9.3   5.1
 10000   8.1  46.6  210  13  7   9.0   5.0 |   8.8  47.8  260  11  6   9.3   5.1
  9750   8.8  47.8  210  12  6   9.8   5.4 |   9.5  49.1  260  11  6  10.0   5.5
  9500   9.6  49.3  210  12  6  10.4   5.7 |  10.2  50.4  260  10  5  10.9   6.0
  9250  10.3  50.5  205  12  6   9.4   5.2 |  11.0  51.8  260   9  5   9.3   5.1
  9000  11.0  51.8  205  11  6   8.1   4.5 |  11.6  52.9  260   9  5   6.9   3.8
  8750  11.6  52.9  205  11  6  10.0   5.5 |  12.2  54.0  260   8  4   9.3   5.1
  8500  12.4  54.3  205  11  6  11.0   6.0 |  12.9  55.2  260   8  4  11.0   6.0
  8250  13.3  55.9  205  11  6  11.6   6.4 |  13.7  56.7  265   7  4  11.5   6.3
  8000  14.1  57.4  205  11  6   8.2   4.5 |  14.5  58.1  265   7  4   7.7   4.2
  7750  14.6  58.3  205  11  5   7.6   4.2 |  15.0  59.0  270   6  3   6.8   3.8
  7500  15.3  59.5  200  11  5  10.7   5.9 |  15.7  60.3  270   6  3  10.2   5.6
  7250  16.1  61.0  200  10  5   9.9   5.4 |  16.4  61.5  275   6  3   9.3   5.1
  7000  16.8  62.2  200  10  5  10.0   5.5 |  17.1  62.8  280   5  3   9.6   5.3
  6750  17.5  63.5  200  10  5   9.8   5.4 |  17.8  64.0  285   5  3   9.4   5.2
  6500  18.3  64.9  200  10  5   9.7   5.3 |  18.5  65.3  290   5  3   9.2   5.1
  6250  19.0  66.2  200  10  5  10.0   5.5 |  19.1  66.4  295   5  3   9.2   5.0
  6000  19.8  67.6  200   9  5  10.7   5.9 |  19.8  67.6  300   5  3   8.9   4.9
  5750  20.7  69.3  200   9  5  13.9   7.6 |  20.4  68.7  305   5  2   5.9   3.3
  5500  21.9  71.4  205   8  4  18.4  10.1 |  20.6  69.1  310   4  2   1.2   0.6
________________________________________________________________________________

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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