Soaring Guidance
Issued by NWS Pueblo, CO

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580
UXUS97 KPUB 161207
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0607 MDT Sunday, June 16, 2024

This forecast is for Villa Grove, CO for Sunday, June 16, 2024:

If the trigger temperature of 69.2 F/20.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 1438 ft/min (7.3 m/s)
   Maximum height of thermals.................. 23610 ft MSL (14653 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1000 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 21156 ft MSL (12199 ft AGL)
Thermal soaring outlook for Monday 06/17....... Excellent

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 05:39:46 / 20:29:11 MDT
Total possible sunshine........... 14 hr 49 min 24 sec (889 min 24 sec)
Altitude of sun at 13:04:29 MDT... 75.08 degrees

Upper air data from numerical model forecast valid on 06/16/2024 at 0600 MDT

Freezing level.................. 16126 ft MSL (7169 ft AGL)
Convective condensation level... 18995 ft MSL (10038 ft AGL)
Lifted condensation level....... 21919 ft MSL (12963 ft AGL)
Lifted index.................... -2.9
K index......................... +18.0

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  -62.0 -79.6   270   37   19   1.1   0.6      M     M       M      M    M
 45000  -59.6 -75.3   275   45   23   3.0   1.7      M     M       M      M    M
 40000  -54.5 -66.1   285   57   29   7.7   4.2      M     M       M      M    M
 38000  -49.9 -57.8   285   50   26   7.6   4.2      M     M       M      M    M
 36000  -45.4 -49.7   285   43   22   7.6   4.2      M     M       M      M    M
 34000  -40.7 -41.3   285   40   20   7.8   4.3      M     M       M      M    M
 32000  -35.4 -31.7   285   37   19   7.7   4.2      M     M       M      M    M
 30000  -30.7 -23.3   285   33   17   8.0   4.4   33.3  92.0     3.5      M    M
 29000  -28.3 -18.9   285   32   16   8.1   4.4   32.7  90.9     3.0      M    M
 28000  -25.9 -14.6   285   30   15   8.2   4.5   32.3  90.1     2.6      M    M
 27000  -23.4 -10.1   280   29   15   8.2   4.5   31.6  88.8     2.1      M    M
 26000  -20.9  -5.6   280   28   14   8.2   4.5   31.0  87.8     1.7      M    M
 25000  -18.4  -1.1   280   27   14   8.5   4.7   30.6  87.0     1.3      M    M
 24000  -16.4   2.5   275   25   13   6.3   3.4   29.5  85.0     0.4      M    M
 23000  -14.5   5.9   270   23   12   6.3   3.5   28.2  82.8    -0.6   1386  7.0
 22000  -12.6   9.3   260   21   11   6.4   3.5   27.1  80.8    -1.6   1299  6.6
 21000  -11.2  11.8   260   20   10   4.4   2.4   25.3  77.6    -3.2   1228  6.2
 20000   -9.9  14.2   260   20   10   4.7   2.6   23.5  74.4    -5.0   1161  5.9
 19500   -9.3  15.3   260   20   10   4.8   2.6   22.7  72.9    -5.8   1128  5.7
 19000   -8.5  16.7   265   19   10   8.5   4.6   22.1  71.8    -6.5   1090  5.5
 18500   -7.1  19.2   265   19   10   9.6   5.3   22.1  71.8    -6.6   1032  5.2
 18000   -5.6  21.9   265   19   10   9.7   5.3   22.1  71.8    -6.6    974  4.9
 17500   -4.2  24.4   265   19   10   9.5   5.2   22.1  71.7    -6.7    916  4.7
 17000   -2.8  27.0   265   19   10   9.6   5.2   22.0  71.6    -6.8    859  4.4
 16500   -1.4  29.5   265   20   10   9.6   5.2   22.0  71.6    -6.9    801  4.1
 16000    0.0  32.0   265   21   11   9.6   5.3   22.0  71.5    -7.0    744  3.8
 15500    1.5  34.7   260   21   11   9.6   5.2   21.9  71.5    -7.0    686  3.5
 15000    3.6  38.5   260   22   11   9.9   5.4   21.9  71.4    -7.1    600  3.0
 14500    4.9  40.8   260   23   12   8.0   4.4   21.7  71.1    -7.3    546  2.8
 14000    6.2  43.2   260   24   12   8.8   4.8   21.6  70.8    -7.5    491  2.5
 13500    7.6  45.7   255   25   13   8.3   4.5   21.5  70.6    -7.7    437  2.2
 13000    8.9  48.0   255   26   13   9.7   5.3   21.3  70.3    -7.9    383  1.9
 12500   10.3  50.5   255   27   14   9.3   5.1   21.3  70.3    -8.0    325  1.7
 12000   11.4  52.5   250   27   14   6.5   3.6   20.8  69.5    -8.4    279  1.4
 11750   11.9  53.4   250   26   13   8.0   4.4   20.7  69.2    -8.6    254  1.3
 11500   12.5  54.5   245   26   13   7.9   4.3   20.5  68.9    -8.8    230  1.2
 11250   13.0  55.4   245   25   13   4.7   2.6   20.3  68.6    -9.0    207  1.1
 11000   13.2  55.8   245   24   12   2.3   1.3   19.8  67.6    -9.6    194  1.0
 10750   13.3  55.9   240   23   12   1.3   0.7   19.2  66.6   -10.2    183  0.9
 10500   13.3  55.9   240   21   11   0.4   0.2   18.5  65.3   -11.0    176  0.9
 10250   13.2  55.8   235   19   10  -3.0  -1.6   17.7  63.9   -11.8    170  0.9
 10000   12.7  54.9   235   18    9  -6.6  -3.6   16.5  61.8   -13.1    179  0.9
  9750   12.2  54.0   230   17    9  -5.3  -2.9   15.4  59.7   -14.4    187  1.0
  9500   11.6  52.9   225   16    8  -6.6  -3.6   14.2  57.5   -15.7    197  1.0
  9250   10.6  51.1   225   14    7 -18.4 -10.1   12.6  54.7   -17.5    218  1.1
  9000    7.9  46.2   225    7    3 -65.6 -36.0    9.1  48.3   -21.1    295  1.5
  8750      M     M     M    M    M     M     M      M     M       M      M    M
  8500      M     M     M    M    M     M     M      M     M       M      M    M
  8250      M     M     M    M    M     M     M      M     M       M      M    M
  8000      M     M     M    M    M     M     M      M     M       M      M    M

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

           06/16/2024 at 0900 MDT          |       06/16/2024 at 1200 MDT
                                           |
CAPE...    +5.0    LI...       +0.6        | CAPE...    +0.1    LI...       +1.5
CINH...   -21.0    K Index... +10.5        | CINH...    -0.1    K Index...  +3.9
                                           |
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 -62.8 -81.0  270  35 18   1.1   0.6 | -62.6 -80.7  265  34 17   0.4   0.2
 45000 -60.1 -76.2  275  43 22   3.5   1.9 | -60.6 -77.1  275  41 21   3.8   2.1
 40000 -54.4 -65.9  280  43 22   7.6   4.1 | -53.9 -65.0  270  40 21   7.4   4.1
 38000 -49.8 -57.6  280  41 21   7.5   4.1 | -49.4 -56.9  270  39 20   7.5   4.1
 36000 -45.3 -49.5  280  40 20   7.5   4.1 | -45.0 -49.0  270  38 20   7.4   4.1
 34000 -40.6 -41.1  275  40 20   7.9   4.3 | -40.3 -40.5  265  38 20   7.9   4.4
 32000 -35.3 -31.5  275  40 21   7.7   4.2 | -35.5 -31.9  265  38 20   7.9   4.3
 30000 -30.3 -22.5  270  38 19   8.4   4.6 | -30.4 -22.7  260  37 19   8.7   4.7
 29000 -27.8 -18.0  270  36 19   8.5   4.6 | -27.9 -18.2  260  37 19   8.7   4.8
 28000 -25.2 -13.4  265  34 18   8.1   4.4 | -25.3 -13.5  260  36 18   8.4   4.6
 27000 -22.9  -9.2  265  31 16   7.9   4.3 | -22.5  -8.5  255  32 17   7.4   4.0
 26000 -20.5  -4.9  265  27 14   7.9   4.3 | -20.3  -4.5  255  29 15   7.4   4.0
 25000 -18.2  -0.8  260  24 12   8.0   4.4 | -18.1  -0.6  250  27 14   7.3   4.0
 24000 -16.1   3.0  265  23 12   6.6   3.6 | -16.0   3.2  250  25 13   6.9   3.8
 23000 -14.0   6.8  270  23 12   6.7   3.7 | -13.9   7.0  255  24 12   6.9   3.8
 22000 -12.0  10.4  270  23 12   6.7   3.7 | -11.9  10.6  255  23 12   6.7   3.7
 21000 -10.5  13.1  270  23 12   4.9   2.7 | -10.1  13.8  255  23 12   5.8   3.2
 20000  -9.0  15.8  260  22 11   5.1   2.8 |  -8.4  16.9  255  24 13   5.8   3.2
 19500  -8.3  17.1  260  22 11   5.3   2.9 |  -7.5  18.5  255  25 13   5.9   3.2
 19000  -7.5  18.5  255  22 11   6.8   3.8 |  -6.7  19.9  250  25 13   4.6   2.5
 18500  -6.5  20.3  255  22 11   7.3   4.0 |  -6.2  20.8  245  24 12   4.8   2.6
 18000  -5.5  22.1  255  22 11   7.5   4.1 |  -5.6  21.9  240  22 12   5.9   3.2
 17500  -4.2  24.4  255  21 11   9.7   5.3 |  -4.4  24.1  240  22 11   9.4   5.1
 17000  -2.7  27.1  255  20 10   9.6   5.3 |  -3.0  26.6  235  21 11   9.2   5.0
 16500  -1.3  29.7  255  18  9   9.2   5.0 |  -1.7  28.9  235  21 11   9.3   5.1
 16000   0.0  32.0  250  16  8   9.1   5.0 |  -0.3  31.5  235  20 10   9.4   5.1
 15500   1.4  34.5  250  13  7   9.0   4.9 |   1.1  34.0  235  19 10   9.7   5.3
 15000   2.7  36.9  250  13  6   8.7   4.8 |   2.6  36.7  235  19 10  10.2   5.6
 14500   4.6  40.3  255  12  6   8.2   4.5 |   4.2  39.6  230  18  9   8.9   4.9
 14000   5.9  42.6  260  13  7   8.4   4.6 |   5.4  41.7  230  17  9   9.4   5.2
 13500   7.2  45.0  265  13  7   6.9   3.8 |   7.5  45.5  225  15  8   8.9   4.9
 13000   8.3  46.9  265  15  8   9.5   5.2 |   8.8  47.8  220  14  7   9.8   5.4
 12500   9.6  49.3  265  16  8   8.9   4.9 |  10.2  50.4  220  14  7   9.4   5.2
 12000  10.7  51.3  260  18  9   7.8   4.3 |  11.5  52.7  220  13  7   9.6   5.3
 11750  11.4  52.5  255  18  9   9.3   5.1 |  12.3  54.1  220  13  7  11.1   6.1
 11500  12.1  53.8  255  18  9   8.9   4.9 |  13.1  55.6  215  13  7  10.7   5.9
 11250  12.7  54.9  250  19 10   6.2   3.4 |  13.9  57.0  215  13  7   9.9   5.4
 11000  13.0  55.4  250  19 10   4.2   2.3 |  14.6  58.3  215  13  7   9.2   5.0
 10750  13.3  55.9  250  19 10   4.1   2.3 |  15.3  59.5  215  13  7  10.2   5.6
 10500  13.5  56.3  245  19 10   3.5   1.9 |  16.1  61.0  215  13  7  10.7   5.9
 10250  13.7  56.7  245  19 10   3.0   1.7 |  16.8  62.2  215  13  7  10.6   5.8
 10000  13.8  56.8  245  17  9   2.4   1.3 |  17.6  63.7  215  12  6  10.6   5.8
  9750  13.9  57.0  240  15  8   3.0   1.7 |  18.4  65.1  215  12  6  10.9   6.0
  9500  14.2  57.6  235  13  7   7.0   3.8 |  19.2  66.6  215  12  6  11.3   6.2
  9250  15.0  59.0  230  11  6  17.5   9.6 |  20.3  68.5  215  11  6  20.3  11.1
  9000  16.8  62.2  225   9  4  32.6  17.9 |  23.1  73.6  210  10  5  66.7  36.6
  8750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  8500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  8250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  8000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           06/16/2024 at 1500 MDT          |       06/16/2024 at 1800 MDT
                                           |
CAPE...    +1.2    LI...       +0.8        | CAPE...    +2.5    LI...       +0.3
CINH...     0.0    K Index... +13.2        | CINH...    -0.4    K Index...  +9.9
                                           |
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 -62.3 -80.1  265  41 21   0.8   0.4 | -61.7 -79.1  265  45 23   2.0   1.1
 45000 -60.0 -76.0  265  47 24   3.5   1.9 | -58.2 -72.8  265  51 27   3.2   1.7
 40000 -54.2 -65.6  250  38 20   7.4   4.1 | -53.1 -63.6  240  41 21   6.2   3.4
 38000 -49.8 -57.6  250  39 20   7.3   4.0 | -49.4 -56.9  235  42 22   6.1   3.3
 36000 -45.4 -49.7  250  40 20   7.3   4.0 | -45.8 -50.4  230  43 22   6.1   3.4
 34000 -40.1 -40.2  250  38 19   7.9   4.3 | -40.6 -41.1  230  41 21   8.1   4.4
 32000 -35.4 -31.7  245  36 18   7.8   4.3 | -35.7 -32.3  230  38 20   8.1   4.4
 30000 -30.3 -22.5  245  35 18   8.6   4.7 | -30.9 -23.6  235  36 18   8.0   4.4
 29000 -27.7 -17.9  250  36 18   8.6   4.7 | -28.5 -19.3  235  35 18   8.0   4.4
 28000 -25.1 -13.2  250  36 18   7.9   4.3 | -26.1 -15.0  240  34 17   7.8   4.3
 27000 -22.9  -9.2  245  35 18   7.3   4.0 | -23.9 -11.0  240  31 16   7.6   4.2
 26000 -20.7  -5.3  245  34 17   7.4   4.0 | -21.6  -6.9  240  29 15   7.6   4.2
 25000 -18.5  -1.3  245  32 17   7.3   4.0 | -19.3  -2.7  235  26 14   7.5   4.1
 24000 -16.3   2.7  245  30 15   7.6   4.2 | -17.0   1.4  235  25 13   7.9   4.3
 23000 -14.0   6.8  245  27 14   7.6   4.2 | -14.6   5.7  235  23 12   7.9   4.3
 22000 -11.7  10.9  240  24 12   7.6   4.2 | -12.2  10.0  235  22 11   8.0   4.4
 21000  -9.9  14.2  240  23 12   5.8   3.2 | -10.1  13.8  235  21 11   6.8   3.7
 20000  -8.2  17.2  240  23 12   6.0   3.3 |  -8.1  17.4  235  21 11   7.0   3.8
 19500  -7.4  18.7  240  23 12   6.1   3.3 |  -7.1  19.2  230  21 11   7.2   3.9
 19000  -6.5  20.3  240  23 12   7.1   3.9 |  -6.1  21.0  230  20 11   8.1   4.4
 18500  -5.4  22.3  240  23 12   7.4   4.1 |  -4.8  23.4  235  21 11   8.4   4.6
 18000  -4.3  24.3  235  24 12   7.5   4.1 |  -3.6  25.5  235  21 11   8.4   4.6
 17500  -3.2  26.2  235  24 12   8.1   4.5 |  -2.3  27.9  235  22 11   8.6   4.7
 17000  -2.0  28.4  230  24 13   8.1   4.4 |  -1.1  30.0  235  22 11   8.6   4.7
 16500  -0.8  30.6  230  25 13   9.0   4.9 |   0.2  32.4  235  23 12   9.0   5.0
 16000   0.6  33.1  225  25 13   9.3   5.1 |   1.6  34.9  235  23 12   9.2   5.1
 15500   2.7  36.9  225  25 13  10.7   5.9 |   3.7  38.7  235  24 12   9.7   5.3
 15000   4.3  39.7  220  25 13  11.5   6.3 |   5.1  41.2  235  25 13  10.4   5.7
 14500   5.6  42.1  220  25 13   7.3   4.0 |   6.3  43.3  230  25 13   6.9   3.8
 14000   7.1  44.8  220  25 13   9.6   5.3 |   7.6  45.7  230  25 13   9.0   4.9
 13500   8.5  47.3  215  25 13   9.3   5.1 |   8.9  48.0  225  26 13   9.5   5.2
 13000  10.0  50.0  215  25 13  10.4   5.7 |  10.4  50.7  225  26 13   9.2   5.0
 12500  11.5  52.7  215  25 13  10.2   5.6 |  11.7  53.1  220  26 13   9.4   5.1
 12000  12.9  55.2  215  25 13   9.4   5.2 |  13.0  55.4  220  26 13   9.3   5.1
 11750  13.7  56.7  215  25 13  11.0   6.0 |  13.8  56.8  220  25 13  10.8   5.9
 11500  14.5  58.1  215  24 13  10.7   5.9 |  14.6  58.3  220  25 13  10.5   5.8
 11250  15.2  59.4  215  24 13  10.3   5.7 |  15.4  59.7  220  25 13  10.3   5.6
 11000  16.0  60.8  215  24 12   9.8   5.4 |  16.1  61.0  220  25 13   9.8   5.4
 10750  16.7  62.1  215  24 12  10.1   5.6 |  16.9  62.4  220  25 13   9.8   5.4
 10500  17.5  63.5  215  24 12  10.1   5.5 |  17.6  63.7  220  25 13   9.7   5.3
 10250  18.3  64.9  215  24 12  10.6   5.8 |  18.3  64.9  215  24 13  10.2   5.6
 10000  19.1  66.4  210  23 12  11.0   6.1 |  19.1  66.4  215  24 12  10.8   5.9
  9750  19.9  67.8  210  23 12  11.6   6.4 |  19.9  67.8  215  23 12  11.0   6.1
  9500  20.8  69.4  210  22 11  11.1   6.1 |  20.7  69.3  215  22 12  10.5   5.8
  9250  21.7  71.1  210  21 11  17.6   9.7 |  21.5  70.7  215  21 11  13.3   7.3
  9000  24.5  76.1  210  17  9  71.0  38.9 |  23.1  73.6  215  16  8  37.1  20.4
  8750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  8500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  8250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  8000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 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 Villa Grove, Colorado at:

                   North Latitude:  38 deg 16 min 03 sec
                   West Longitude: 105 deg 53 min 37 sec
                   Elevation: 7986 feet (2434 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.

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