Soaring Guidance
Issued by NWS Pueblo, CO

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254
UXUS97 KPUB 170949
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0349 MDT Sunday, July 17, 2016

This forecast is for Sunday, July 17, 2016:

If the trigger temperature of 79.3 F/26.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1517 ft/min (7.7 m/s)
   Maximum height of thermals.................. 21509 ft MSL (14751 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10875 ft MSL (4117 ft AGL)
Thermal soaring outlook for Monday 07/18....... Good

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

Remarks...

Sunrise/Sunset.................... 05:47:52 / 20:22:41 MDT
Total possible sunshine........... 14 hr 34 min 50 sec (874 min 50 sec)
Altitude of sun at 13:05:11 MDT... 72.04 degrees

Upper air data from numerical model forecast valid on 07/17/2016 at 0600 MDT

Freezing level.................. 16369 ft MSL (9611 ft AGL)
Convective condensation level... 19788 ft MSL (13030 ft AGL)
Lifted condensation level....... 19900 ft MSL (13142 ft AGL)
Lifted index.................... -0.3
K index......................... +14.5

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  -63.4 -82.1   250   21   11   1.8   1.0      M     M       M      M    M
 45000  -58.9 -74.0   260   34   18   5.6   3.1      M     M       M      M    M
 40000  -50.1 -58.2   260   51   26   5.0   2.8      M     M       M      M    M
 38000  -47.1 -52.8   255   48   25   5.0   2.8      M     M       M      M    M
 36000  -44.1 -47.4   255   45   23   4.8   2.7      M     M       M      M    M
 34000  -40.0 -40.0   255   40   21   7.2   3.9      M     M       M      M    M
 32000  -35.7 -32.3   260   36   18   7.0   3.8      M     M       M      M    M
 30000  -31.1 -24.0   255   31   16   7.7   4.2   38.9 102.1     7.3      M    M
 29000  -28.8 -19.8   255   30   15   7.7   4.2   38.2 100.7     6.8      M    M
 28000  -26.0 -14.8   255   27   14   7.1   3.9   37.3  99.1     6.2      M    M
 27000  -23.9 -11.0   255   27   14   7.1   3.9   36.1  97.1     5.4      M    M
 26000  -21.7  -7.1   255   27   14   7.1   3.9   35.2  95.3     4.6      M    M
 25000  -19.6  -3.3   255   26   13   6.6   3.6   34.3  93.8     4.0      M    M
 24000  -17.9  -0.2   255   25   13   5.7   3.1   32.8  91.0     2.7      M    M
 23000  -16.2   2.8   255   24   12   5.7   3.1   31.3  88.4     1.5      M    M
 22000  -14.6   5.7   250   23   12   6.8   3.7   30.0  86.0     0.4      M    M
 21000  -12.3   9.9   250   23   12   8.0   4.4   29.3  84.7    -0.3   1467  7.5
 20000   -9.9  14.2   245   22   11   8.1   4.4   28.7  83.7    -0.9   1368  7.1
 19500   -8.8  16.2   240   22   11   8.1   4.5   28.5  83.2    -1.2   1319  6.7
 19000   -7.5  18.5   240   21   11   9.5   5.2   28.3  83.0    -1.4   1265  6.4
 18500   -6.1  21.0   240   21   11   9.4   5.2   28.3  82.9    -1.5   1208  6.1
 18000   -4.7  23.5   240   20   11   9.3   5.1   28.2  82.8    -1.5   1151  5.8
 17500   -3.3  26.1   245   19   10   9.2   5.0   28.1  82.6    -1.6   1096  5.6
 17000   -2.0  28.4   250   18    9   9.2   5.0   28.0  82.4    -1.7   1040  5.3
 16500   -0.6  30.9   250   17    9   9.1   5.0   27.9  82.2    -1.8    985  5.0
 16000    0.7  33.3   255   16    8   9.1   5.0   27.8  82.0    -2.0    930  4.7
 15500    2.1  35.8   260   15    8   8.9   4.9   27.7  81.8    -2.1    875  4.4
 15000    3.4  38.1   265   15    8   8.9   4.9   27.5  81.6    -2.2    820  4.2
 14500    4.7  40.5   270   14    7   9.2   5.1   27.4  81.3    -2.4    766  3.9
 14000    6.9  44.4   275   13    7   9.8   5.4   27.4  81.3    -2.4    679  3.5
 13500    8.3  46.9   280   13    7   9.8   5.4   27.4  81.3    -2.4    621  3.2
 13000    9.8  49.6   280   12    6   9.8   5.4   27.4  81.3    -2.5    563  2.9
 12500   11.2  52.2   285   12    6   9.0   5.0   27.4  81.3    -2.5    505  2.6
 12000   12.6  54.7   285   11    5   9.1   5.0   27.2  81.0    -2.6    450  2.3
 11750   13.2  55.8   285   10    5   9.2   5.0   27.2  81.0    -2.7    423  2.1
 11500   13.9  57.0   290   10    5   8.7   4.8   27.2  80.9    -2.8    395  2.0
 11250   14.5  58.1   290    9    5   8.6   4.7   27.1  80.7    -2.9    370  1.9
 11000   15.2  59.4   290    8    4   9.0   4.9   27.0  80.6    -3.0    342  1.7
 10750   15.8  60.4   295    7    4   9.1   5.0   26.9  80.5    -3.1    315  1.6
 10500   16.5  61.7   295    7    3   8.5   4.6   26.9  80.4    -3.1    288  1.5
 10250   17.1  62.8   300    6    3   7.5   4.1   26.7  80.1    -3.3    263  1.3
 10000   17.6  63.7   305    6    3   8.8   4.8   26.6  79.9    -3.4    239  1.2
  9750   18.3  64.9   310    5    3  10.0   5.5   26.6  79.8    -3.5    210  1.1
  9500   19.1  66.4   315    5    2   9.0   4.9   26.6  79.8    -3.5    181  0.9
  9250   19.7  67.5   320    5    2   7.9   4.4   26.5  79.6    -3.6    156  0.8
  9000   20.2  68.4   320    5    3   7.9   4.3   26.3  79.4    -3.8    131  0.7
  8750   20.9  69.6   320    5    3   9.8   5.4   26.2  79.2    -3.9    105  0.5
  8500   21.6  70.9   320    6    3   6.5   3.6   26.2  79.1    -4.0     77  0.4
  8250   21.8  71.2   315    7    4   1.8   1.0   25.7  78.2    -4.4     62  0.3
  8000   21.9  71.4   310    8    4   1.2   0.7   25.1  77.2    -5.0     51  0.3
  7750   22.1  71.8   310   10    5   3.4   1.9   24.5  76.1    -5.6     39  0.2
  7500   21.9  71.4   305   11    5 -15.6  -8.6   23.6  74.5    -6.6     38  0.2
  7250   19.6  67.3   300   10    5 -35.3 -19.4   21.1  69.9    -9.2     97  0.5
  7000   17.4  63.3   300    9    5 -20.2 -11.1   18.5  65.4   -11.7    157  0.8
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           07/17/2016 at 0900 MDT          |       07/17/2016 at 1200 MDT
                                           |
K index... +15.2  LI... +272.9             | K index... +23.4  LI... +270.8
CAPE... +20.8  CIN... -66.8                | CAPE... +415.9  CIN... -20.5
                                           |
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  245  25 13   2.0   1.1 | -64.1 -83.4  245  31 16   1.7   0.9
 45000 -58.9 -74.0  255  36 19   5.9   3.2 | -58.9 -74.0  255  42 22   6.4   3.5
 40000 -50.0 -58.0  260  49 25   4.4   2.4 | -49.7 -57.5  260  48 25   4.3   2.4
 38000 -47.4 -53.3  260  47 24   4.4   2.4 | -47.1 -52.8  260  49 25   4.4   2.4
 36000 -44.8 -48.6  260  45 23   4.3   2.4 | -44.4 -47.9  260  49 25   4.4   2.4
 34000 -40.1 -40.2  265  41 21   8.1   4.5 | -40.1 -40.2  260  43 22   7.6   4.2
 32000 -35.2 -31.4  265  37 19   8.1   4.5 | -35.5 -31.9  260  37 19   7.5   4.1
 30000 -31.0 -23.8  265  32 16   7.0   3.8 | -30.6 -23.1  260  31 16   7.4   4.0
 29000 -28.4 -19.1  265  29 15   7.0   3.8 | -28.3 -18.9  255  29 15   7.4   4.0
 28000 -26.2 -15.2  265  26 13   7.6   4.2 | -26.1 -15.0  255  27 14   7.4   4.1
 27000 -24.0 -11.2  265  25 13   7.5   4.1 | -23.9 -11.0  260  24 13   7.4   4.1
 26000 -21.7  -7.1  260  23 12   7.5   4.1 | -21.7  -7.1  270  23 12   7.4   4.1
 25000 -19.4  -2.9  255  22 11   6.9   3.8 | -19.5  -3.1  275  21 11   7.2   4.0
 24000 -17.6   0.3  255  21 11   6.1   3.3 | -17.3   0.9  275  21 11   7.1   3.9
 23000 -15.8   3.6  255  21 11   6.1   3.4 | -15.2   4.6  270  22 11   7.1   3.9
 22000 -14.0   6.8  255  20 10   6.6   3.6 | -13.1   8.4  270  22 11   6.9   3.8
 21000 -12.0  10.4  250  19 10   6.9   3.8 | -11.2  11.8  260  22 11   6.8   3.7
 20000 -10.0  14.0  250  19 10   7.1   3.9 |  -9.2  15.4  250  22 11   6.9   3.8
 19500  -9.0  15.8  245  19 10   7.2   4.0 |  -8.2  17.2  250  22 11   7.1   3.9
 19000  -7.8  18.0  245  19 10   8.8   4.9 |  -7.1  19.2  245  21 11   8.5   4.6
 18500  -6.5  20.3  245  19 10   8.7   4.8 |  -5.9  21.4  245  20 10   8.4   4.6
 18000  -5.2  22.6  250  19 10   9.1   5.0 |  -4.7  23.5  245  19 10   8.5   4.7
 17500  -3.9  25.0  250  19 10   9.3   5.1 |  -3.4  25.9  245  18  9   8.5   4.7
 17000  -2.5  27.5  245  18  9   9.3   5.1 |  -2.2  28.0  245  17  9   8.6   4.7
 16500  -1.1  30.0  250  18  9   9.4   5.1 |  -0.9  30.4  245  16  8   8.8   4.8
 16000   0.3  32.5  250  17  9   9.4   5.2 |   0.3  32.5  240  15  8   8.7   4.8
 15500   1.7  35.1  250  16  8   8.9   4.9 |   1.6  34.9  240  14  7   8.8   4.8
 15000   3.0  37.4  255  15  8   8.9   4.9 |   3.0  37.4  240  13  7   8.8   4.8
 14500   5.0  41.0  260  14  7   9.9   5.4 |   4.9  40.8  240  11  6   9.0   4.9
 14000   6.5  43.7  265  14  7   9.8   5.4 |   6.3  43.3  240  10  5   8.9   4.9
 13500   7.9  46.2  270  13  7   9.2   5.1 |   7.6  45.7  235   9  4   8.8   4.9
 13000   9.3  48.7  270  12  6   9.2   5.1 |   8.9  48.0  230   7  4   9.0   4.9
 12500  10.6  51.1  275  10  5   8.6   4.7 |  10.1  50.2  215   6  3   8.3   4.5
 12000  11.9  53.4  275   8  4   8.8   4.8 |  11.3  52.3  185   5  2   8.7   4.8
 11750  12.6  54.7  270   7  4   8.5   4.7 |  11.9  53.4  170   5  2   8.5   4.7
 11500  13.2  55.8  270   6  3   9.6   5.3 |  12.5  54.5  155   5  3  10.0   5.5
 11250  13.9  57.0  270   5  3   9.1   5.0 |  13.2  55.8  145   5  3  10.2   5.6
 11000  14.5  58.1  270   4  2   7.7   4.2 |  13.9  57.0  140   6  3   8.9   4.9
 10750  15.1  59.2  270   3  2   7.9   4.3 |  14.5  58.1  135   6  3   9.1   5.0
 10500  15.7  60.3  275   2  1   8.5   4.6 |  15.2  59.4  135   6  3   9.8   5.4
 10250  16.3  61.3  280   1  1   9.4   5.1 |  16.0  60.8  135   6  3  10.6   5.8
 10000  17.0  62.6  315   1  0   7.9   4.3 |  16.7  62.1  130   6  3   9.9   5.4
  9750  17.5  63.5  005   1  1   7.0   3.8 |  17.4  63.3  130   6  3   9.6   5.2
  9500  18.0  64.4  025   2  1   6.8   3.8 |  18.1  64.6  130   6  3   9.7   5.3
  9250  18.5  65.3  015   3  1   6.3   3.5 |  18.9  66.0  130   6  3   9.7   5.3
  9000  18.9  66.0  005   4  2   6.3   3.5 |  19.6  67.3  130   6  3   9.7   5.3
  8750  19.3  66.7  005   5  2   5.8   3.2 |  20.3  68.5  125   6  3   9.6   5.3
  8500  19.7  67.5  360   6  3   5.8   3.2 |  21.0  69.8  125   7  3  10.3   5.6
  8250  20.1  68.2  355   7  4   6.2   3.4 |  21.8  71.2  125   7  3  11.1   6.1
  8000  20.5  68.9  350   9  4   5.3   2.9 |  22.6  72.7  125   7  3  10.3   5.7
  7750  20.9  69.6  350  10  5   8.7   4.8 |  23.4  74.1  125   7  3  12.5   6.9
  7500  21.7  71.1  350  10  5  10.0   5.5 |  24.4  75.9  125   7  3  13.3   7.3
  7250  22.2  72.0  350   9  5   7.0   3.9 |  25.3  77.5  120   7  3  11.3   6.2
  7000  22.8  73.0  345   9  5   9.6   5.3 |  26.1  79.0  120   7  3  13.0   7.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/17/2016 at 1500 MDT          |       07/17/2016 at 1800 MDT
                                           |
K index... +23.9  LI... +272.1             | K index... +19.3  LI... +273.5
CAPE... +195.9  CIN... -42.5               | CAPE... +38.2  CIN... -54.5
                                           |
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 -64.3 -83.7  250  28 15   1.1   0.6 | -64.6 -84.3  245  28 15   0.6   0.3
 45000 -59.4 -74.9  255  40 21   6.8   3.7 | -59.9 -75.8  260  39 20   7.4   4.1
 40000 -49.5 -57.1  265  46 24   4.9   2.7 | -49.3 -56.7  270  44 23   5.2   2.9
 38000 -46.6 -51.9  265  50 26   4.9   2.7 | -46.1 -51.0  270  54 28   5.2   2.9
 36000 -43.6 -46.5  265  54 28   5.2   2.8 | -43.0 -45.4  265  64 33   5.6   3.0
 34000 -39.5 -39.1  260  47 24   7.1   3.9 | -38.9 -38.0  265  55 28   6.9   3.8
 32000 -35.2 -31.4  260  39 20   7.0   3.8 | -34.3 -29.7  265  44 22   7.5   4.1
 30000 -30.3 -22.5  260  35 18   7.3   4.0 | -29.9 -21.8  260  36 19   7.3   4.0
 29000 -28.1 -18.6  260  33 17   7.3   4.0 | -27.8 -18.0  260  33 17   7.3   4.0
 28000 -25.9 -14.6  260  31 16   7.6   4.2 | -25.6 -14.1  255  30 16   7.0   3.8
 27000 -23.7 -10.7  265  30 15   7.6   4.2 | -23.5 -10.3  260  29 15   7.0   3.8
 26000 -21.4  -6.5  265  28 15   7.6   4.1 | -21.4  -6.5  260  28 14   7.0   3.8
 25000 -19.1  -2.4  270  27 14   6.6   3.6 | -19.3  -2.7  265  26 14   6.7   3.7
 24000 -17.4   0.7  265  26 13   6.0   3.3 | -17.4   0.7  260  25 13   6.6   3.6
 23000 -15.7   3.7  265  24 13   6.0   3.3 | -15.5   4.1  260  24 12   6.7   3.7
 22000 -13.9   7.0  260  23 12   7.7   4.2 | -13.5   7.7  260  23 12   8.4   4.6
 21000 -11.4  11.5  260  22 11   8.4   4.6 | -10.9  12.4  260  21 11   8.9   4.9
 20000  -9.0  15.8  255  21 11   8.5   4.7 |  -8.3  17.1  260  20 10   9.0   4.9
 19500  -7.8  18.0  255  20 10   8.7   4.8 |  -7.0  19.4  260  19 10   9.1   5.0
 19000  -6.5  20.3  255  19 10   9.3   5.1 |  -5.6  21.9  260  18  9   9.5   5.2
 18500  -5.1  22.8  255  18  9   9.3   5.1 |  -4.2  24.4  260  17  9   9.5   5.2
 18000  -3.7  25.3  255  17  9   9.2   5.1 |  -2.8  27.0  255  16  8   9.4   5.2
 17500  -2.4  27.7  255  15  8   9.2   5.1 |  -1.4  29.5  255  15  8   9.4   5.2
 17000  -1.0  30.2  250  13  6   9.1   5.0 |   0.0  32.0  255  13  7   9.4   5.1
 16500   0.3  32.5  245  11  5   8.8   4.8 |   1.4  34.5  250  12  6   9.0   5.0
 16000   1.6  34.9  235   9  5   8.8   4.8 |   2.7  36.9  245  11  6   9.1   5.0
 15500   2.9  37.2  220   8  4   8.6   4.7 |   4.8  40.6  235  10  5   9.1   5.0
 15000   4.8  40.6  205   8  4   8.6   4.7 |   6.1  43.0  225  10  5   9.2   5.0
 14500   6.1  43.0  195   8  4   8.4   4.6 |   7.5  45.5  220  10  5   8.7   4.8
 14000   7.3  45.1  190   9  4   8.4   4.6 |   8.8  47.8  210  10  5   8.7   4.8
 13500   8.6  47.5  180   9  5   8.7   4.8 |  10.1  50.2  205  11  6   8.7   4.8
 13000   9.9  49.8  180  10  5   8.6   4.7 |  11.4  52.5  200  12  6   8.7   4.8
 12500  11.2  52.2  175  10  5   9.2   5.1 |  12.7  54.9  195  12  6   8.2   4.5
 12000  12.5  54.5  170  11  6   9.2   5.0 |  13.9  57.0  190  13  7   8.3   4.5
 11750  13.2  55.8  170  11  6   9.1   5.0 |  14.5  58.1  190  14  7   8.0   4.4
 11500  13.9  57.0  170  12  6   9.4   5.2 |  15.2  59.4  190  14  7   9.5   5.2
 11250  14.6  58.3  170  12  6   9.5   5.2 |  15.9  60.6  185  14  7   9.2   5.1
 11000  15.3  59.5  165  12  6   9.4   5.2 |  16.5  61.7  185  15  8   7.7   4.2
 10750  16.0  60.8  165  12  6   9.2   5.1 |  17.1  62.8  185  15  8   8.0   4.4
 10500  16.7  62.1  165  12  6  10.2   5.6 |  17.7  63.9  180  16  8   8.3   4.6
 10250  17.5  63.5  165  12  6  11.0   6.0 |  18.3  64.9  180  16  8   8.7   4.8
 10000  18.2  64.8  165  12  6   9.6   5.3 |  18.9  66.0  180  16  8   8.8   4.8
  9750  18.9  66.0  165  12  6   8.8   4.9 |  19.6  67.3  180  16  8   8.8   4.8
  9500  19.6  67.3  165  12  6   9.5   5.2 |  20.2  68.4  175  16  8   9.0   4.9
  9250  20.3  68.5  165  12  6   9.8   5.4 |  20.9  69.6  175  16  8   9.1   5.0
  9000  21.0  69.8  165  12  6   9.9   5.5 |  21.5  70.7  175  16  8   9.4   5.2
  8750  21.8  71.2  165  12  6  10.6   5.8 |  22.3  72.1  175  16  8  10.3   5.7
  8500  22.6  72.7  165  12  6  10.6   5.8 |  23.1  73.6  175  16  8  10.4   5.7
  8250  23.4  74.1  165  12  6  10.5   5.8 |  23.8  74.8  175  16  8  10.1   5.6
  8000  24.2  75.6  165  12  6  10.5   5.8 |  24.6  76.3  175  15  8  10.4   5.7
  7750  25.0  77.0  165  12  6  10.7   5.9 |  25.3  77.5  175  15  8   9.5   5.2
  7500  25.8  78.4  165  12  6  11.8   6.5 |  26.0  78.8  175  15  8   7.8   4.3
  7250  26.7  80.1  165  12  6  12.5   6.9 |  26.5  79.7  175  14  7   7.4   4.1
  7000  27.6  81.7  165  11  6  12.1   6.6 |  27.0  80.6  170  13  7   7.6   4.2
  6750     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) 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 Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 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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