Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 031020
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0420 MDT Thursday, September 3, 2015

This forecast is for Thursday, September 3, 2015:

If the trigger temperature of 74.7 F/23.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 875 ft/min (4.4 m/s)
   Maximum height of thermals.................. 17908 ft MSL (11150 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12198 ft MSL (5440 ft AGL)
Thermal soaring outlook for Friday 09/04....... Good

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

Remarks...

Sunrise/Sunset.................... 06:29:27 / 19:28:01 MDT
Total possible sunshine........... 12 hr 58 min 34 sec (778 min 34 sec)
Altitude of sun at 12:58:17 MDT... 58.50 degrees

Upper air data from numerical model forecast valid on 09/03/2015 at 0600 MDT

Freezing level.................. 15745 ft MSL (8987 ft AGL)
Convective condensation level... 16127 ft MSL (9369 ft AGL)
Lifted condensation level....... 16320 ft MSL (9563 ft AGL)
Lifted index.................... -2.0
K index......................... +29.8

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -64.2 -83.6   230   37   19   2.5   1.3      M     M       M      M    M
 45000  -60.0 -76.0   225   43   22   3.2   1.8      M     M       M      M    M
 40000  -54.5 -66.1   240   39   20   7.4   4.0      M     M       M      M    M
 38000  -50.0 -58.0   240   38   20   7.5   4.1      M     M       M      M    M
 36000  -45.5 -49.9   235   37   19   7.3   4.0      M     M       M      M    M
 34000  -40.3 -40.5   235   32   17   8.8   4.8      M     M       M      M    M
 32000  -35.1 -31.2   235   27   14   8.6   4.7      M     M       M      M    M
 30000  -29.6 -21.3   225   22   11   8.0   4.4   40.1 104.3    10.0      M    M
 29000  -27.2 -17.0   220   20   11   8.0   4.4   39.5 103.2     9.6      M    M
 28000  -24.9 -12.8   210   19   10   7.2   3.9   38.9 102.1     9.2      M    M
 27000  -22.8  -9.0   210   19   10   7.1   3.9   37.8 100.1     8.4      M    M
 26000  -20.7  -5.3   210   18    9   7.1   3.9   36.8  98.3     7.6      M    M
 25000  -18.6  -1.5   205   18    9   7.0   3.9   36.0  96.7     6.9      M    M
 24000  -16.7   1.9   205   17    9   6.6   3.6   34.8  94.6     6.0      M    M
 23000  -14.7   5.5   200   16    8   6.6   3.6   33.6  92.5     5.0      M    M
 22000  -12.8   9.0   200   15    8   6.6   3.6   32.6  90.7     4.2      M    M
 21000  -10.9  12.4   200   14    7   6.5   3.6   31.4  88.6     3.1      M    M
 20000   -9.0  15.8   195   12    6   6.6   3.6   30.3  86.6     2.1      M    M
 19500   -8.0  17.6   195   12    6   6.6   3.6   29.8  85.7     1.7      M    M
 19000   -7.1  19.2   195   11    6   6.4   3.5   29.3  84.7     1.2      M    M
 18500   -6.2  20.8   195   10    5   6.5   3.6   28.7  83.7     0.7      M    M
 18000   -5.2  22.6   190   10    5   6.7   3.7   28.2  82.7     0.2      M    M
 17500   -4.2  24.4   190   10    5   7.3   4.0   27.7  81.9    -0.3   1045  5.3
 17000   -3.1  26.4   195   10    5   7.2   4.0   27.3  81.2    -0.7    999  5.1
 16500   -2.0  28.4   190   11    5   8.0   4.4   27.0  80.5    -1.0    951  4.8
 16000   -0.9  30.4   190   11    6   8.0   4.4   26.7  80.0    -1.3    901  4.6
 15500    0.3  32.5   190   12    6   8.3   4.5   26.4  79.5    -1.6    852  4.3
 15000    2.2  36.0   190   13    7   8.5   4.7   26.1  79.0    -2.0    774  3.9
 14500    3.4  38.1   190   14    7   8.7   4.8   25.9  78.6    -2.2    722  3.7
 14000    4.7  40.5   190   15    8   8.8   4.8   25.7  78.3    -2.4    669  3.4
 13500    6.0  42.8   190   15    8   8.9   4.9   25.6  78.1    -2.6    616  3.1
 13000    7.3  45.1   190   14    7   9.0   4.9   25.5  77.9    -2.7    561  2.9
 12500    8.6  47.5   195   14    7   8.5   4.6   25.4  77.7    -2.9    507  2.6
 12000    9.9  49.8   195   12    6   9.4   5.2   25.2  77.4    -3.1    453  2.3
 11750   10.6  51.1   195   12    6   9.4   5.2   25.2  77.3    -3.1    424  2.2
 11500   11.3  52.3   195   11    6   8.9   4.9   25.2  77.3    -3.1    396  2.0
 11250   11.9  53.4   200   10    5   8.5   4.7   25.1  77.1    -3.3    370  1.9
 11000   12.6  54.7   200    9    5   8.8   4.8   25.0  77.0    -3.3    343  1.7
 10750   13.2  55.8   205    8    4   8.8   4.8   24.9  76.8    -3.4    316  1.6
 10500   13.9  57.0   205    7    4   8.6   4.7   24.8  76.7    -3.5    289  1.5
 10250   14.5  58.1   210    6    3   8.2   4.5   24.7  76.5    -3.6    262  1.3
 10000   15.1  59.2   220    5    3   8.0   4.4   24.6  76.3    -3.7    237  1.2
  9750   15.8  60.4   230    5    2   8.2   4.5   24.5  76.0    -3.8    211  1.1
  9500   16.4  61.5   240    5    2   8.1   4.4   24.3  75.8    -4.0    185  0.9
  9250   17.0  62.6   255    5    2   7.9   4.3   24.2  75.6    -4.1    159  0.8
  9000   17.6  63.7   270    5    2   7.8   4.3   24.1  75.3    -4.2    133  0.7
  8750   18.2  64.8   280    5    3   9.0   5.0   24.0  75.1    -4.3    107  0.5
  8500   18.9  66.0   285    7    3   7.0   3.9   23.9  75.0    -4.4     80  0.4
  8250   19.2  66.6   290    8    4   3.5   1.9   23.5  74.3    -4.8     63  0.3
  8000   19.4  66.9   295    9    5   1.9   1.0   23.0  73.4    -5.4     50  0.3
  7750   19.6  67.3   295   10    5   6.1   3.3   22.5  72.4    -5.9     37  0.2
  7500   19.9  67.8   285   11    6  -4.2  -2.3   22.1  71.7    -6.4     21  0.1
  7250   18.7  65.7   285   10    5 -19.6 -10.8   20.6  69.1    -7.9     48  0.2
  7000   17.4  63.3   290    8    4 -10.5  -5.7   19.1  66.3    -9.5     79  0.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           09/03/2015 at 0900 MDT          |       09/03/2015 at 1200 MDT
                                           |
K index... +29.4  LI... +271.5             | K index... +29.0  LI... +271.4
CAPE... +131.9  CIN... -15.7               | CAPE... +187.8  CIN... -2.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.7 -82.7  235  38 20   1.9   1.0 | -63.9 -83.0  230  40 21   1.8   1.0
 45000 -60.1 -76.2  235  44 22   3.4   1.9 | -60.6 -77.1  230  45 23   2.5   1.4
 40000 -54.4 -65.9  240  42 21   7.1   3.9 | -55.8 -68.4  240  41 21   8.8   4.9
 38000 -50.1 -58.2  235  38 20   7.2   4.0 | -50.4 -58.7  240  39 20   9.0   5.0
 36000 -45.7 -50.3  235  35 18   7.1   3.9 | -45.0 -49.0  240  37 19   9.1   5.0
 34000 -40.6 -41.1  235  32 16   8.7   4.8 | -39.8 -39.6  235  34 17   8.5   4.7
 32000 -35.4 -31.7  230  28 14   8.6   4.7 | -34.1 -29.4  225  30 15   9.2   5.0
 30000 -29.8 -21.6  220  26 13   8.3   4.6 | -29.3 -20.7  225  29 15   8.1   4.4
 29000 -27.3 -17.1  220  25 13   8.4   4.6 | -26.9 -16.4  225  29 15   8.1   4.4
 28000 -24.8 -12.6  215  25 13   7.5   4.1 | -24.5 -12.1  220  29 15   7.4   4.1
 27000 -22.7  -8.9  215  24 12   7.3   4.0 | -22.4  -8.3  220  28 15   7.3   4.0
 26000 -20.5  -4.9  210  23 12   7.3   4.0 | -20.2  -4.4  220  27 14   7.3   4.0
 25000 -18.4  -1.1  210  22 11   7.2   3.9 | -18.0  -0.4  220  27 14   7.3   4.0
 24000 -16.5   2.3  210  21 11   6.3   3.5 | -16.1   3.0  215  24 13   6.6   3.6
 23000 -14.6   5.7  205  19 10   6.4   3.5 | -14.1   6.6  215  22 11   6.6   3.6
 22000 -12.8   9.0  205  18  9   6.4   3.5 | -12.2  10.0  210  20 10   6.6   3.6
 21000 -11.0  12.2  200  17  9   6.3   3.4 | -10.4  13.3  205  19 10   6.1   3.3
 20000  -9.2  15.4  195  16  8   6.3   3.5 |  -8.6  16.5  200  18  9   6.1   3.3
 19500  -8.2  17.2  190  16  8   6.4   3.5 |  -7.7  18.1  195  18  9   6.1   3.3
 19000  -7.4  18.7  185  16  8   5.9   3.2 |  -6.8  19.8  190  18  9   6.4   3.5
 18500  -6.5  20.3  180  15  8   5.9   3.2 |  -5.9  21.4  190  18  9   6.4   3.5
 18000  -5.7  21.7  180  15  8   6.3   3.5 |  -5.0  23.0  185  17  9   6.5   3.5
 17500  -4.6  23.7  175  15  8   7.7   4.2 |  -4.0  24.8  185  17  9   6.5   3.5
 17000  -3.5  25.7  175  15  8   7.7   4.2 |  -3.1  26.4  185  16  8   6.5   3.5
 16500  -2.4  27.7  170  15  8   7.9   4.3 |  -2.2  28.0  185  15  8   6.5   3.6
 16000  -1.2  29.8  170  15  8   7.9   4.4 |  -1.2  29.8  180  14  7   6.5   3.6
 15500  -0.1  31.8  170  14  7   8.3   4.5 |   0.2  32.4  175  13  7   6.8   3.7
 15000   1.8  35.2  170  14  7   8.6   4.7 |   1.1  34.0  175  12  6   6.8   3.7
 14500   3.0  37.4  170  14  7   8.6   4.7 |   2.2  36.0  170  11  6   7.9   4.4
 14000   4.3  39.7  175  13  7   8.7   4.8 |   3.4  38.1  160  10  5   8.4   4.6
 13500   5.6  42.1  175  13  6   9.0   5.0 |   4.6  40.3  155   9  5   9.1   5.0
 13000   7.0  44.6  175  11  6   9.4   5.1 |   6.0  42.8  150   9  4   9.8   5.4
 12500   8.4  47.1  180   9  5   8.8   4.8 |   7.4  45.3  145   8  4   8.9   4.9
 12000   9.7  49.5  175   8  4   8.6   4.7 |   8.7  47.7  130   7  3   9.7   5.3
 11750  10.3  50.5  175   7  4   8.3   4.5 |   9.4  48.9  120   6  3   9.5   5.2
 11500  10.9  51.6  175   6  3   9.3   5.1 |  10.1  50.2  115   6  3   9.4   5.1
 11250  11.6  52.9  170   5  3   8.9   4.9 |  10.8  51.4  115   6  3   9.4   5.2
 11000  12.2  54.0  165   5  2   7.6   4.2 |  11.5  52.7  115   6  3   9.6   5.3
 10750  12.8  55.0  155   4  2   7.9   4.3 |  12.2  54.0  110   6  3   9.6   5.3
 10500  13.4  56.1  145   3  2   7.9   4.3 |  13.0  55.4  110   6  3   9.5   5.2
 10250  14.0  57.2  125   3  1   8.2   4.5 |  13.7  56.7  105   6  3   9.2   5.1
 10000  14.6  58.3  105   3  1   8.2   4.5 |  14.4  57.9  105   6  3   9.9   5.4
  9750  15.2  59.4  085   3  1   8.2   4.5 |  15.1  59.2  105   6  3  10.6   5.8
  9500  15.8  60.4  070   3  2   7.9   4.4 |  15.9  60.6  105   6  3  10.2   5.6
  9250  16.4  61.5  060   4  2   7.3   4.0 |  16.6  61.9  105   6  3   9.3   5.1
  9000  16.9  62.4  050   5  2   6.9   3.8 |  17.3  63.1  105   5  3   9.4   5.1
  8750  17.4  63.3  040   6  3   7.1   3.9 |  18.1  64.6  100   5  3  10.8   5.9
  8500  17.9  64.2  030   6  3   6.5   3.5 |  18.9  66.0  100   5  3  11.1   6.1
  8250  18.4  65.1  020   7  4   5.7   3.1 |  19.7  67.5  100   5  3  10.4   5.7
  8000  18.7  65.7  005   8  4   5.0   2.7 |  20.5  68.9  100   5  3  10.8   5.9
  7750  19.1  66.4  355   8  4   7.2   3.9 |  21.2  70.2  100   5  3   9.0   4.9
  7500  19.6  67.3  340   8  4   7.4   4.1 |  21.9  71.4  100   5  3  10.0   5.5
  7250  20.0  68.0  335   7  4   4.8   2.6 |  22.8  73.0  100   5  3  13.6   7.5
  7000  20.3  68.5  330   7  3   6.5   3.6 |  23.7  74.7  095   5  2  11.8   6.5
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/03/2015 at 1500 MDT          |       09/03/2015 at 1800 MDT
                                           |
K index... +26.6  LI... +271.7             | K index... +30.8  LI... +270.9
CAPE... +79.2  CIN... -14.0                | CAPE... +302.9  CIN... -11.5
                                           |
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 -64.5 -84.1  230  37 19   0.5   0.3 | -64.7 -84.5  235  34 17  -0.1  -0.1
 45000 -62.0 -79.6  240  40 21   4.2   2.3 | -62.6 -80.7  245  39 20   4.9   2.7
 40000 -55.0 -67.0  255  33 17   8.6   4.7 | -54.6 -66.3  245  32 16   8.5   4.7
 38000 -49.8 -57.6  245  28 15   8.7   4.8 | -49.5 -57.1  245  30 15   8.6   4.7
 36000 -44.5 -48.1  235  24 12   8.7   4.8 | -44.3 -47.7  245  28 15   8.6   4.7
 34000 -39.3 -38.7  235  28 14   8.7   4.8 | -39.0 -38.2  245  32 16   8.9   4.9
 32000 -34.1 -29.4  230  33 17   8.5   4.7 | -33.7 -28.7  240  37 19   8.7   4.8
 30000 -28.6 -19.5  230  34 17   7.9   4.4 | -28.2 -18.8  240  37 19   8.0   4.4
 29000 -26.3 -15.3  230  33 17   7.9   4.4 | -25.8 -14.4  240  37 19   8.1   4.4
 28000 -23.9 -11.0  230  33 17   7.4   4.1 | -23.5 -10.3  235  36 19   7.0   3.8
 27000 -21.8  -7.2  225  32 17   7.3   4.0 | -21.5  -6.7  235  36 18   6.6   3.6
 26000 -19.6  -3.3  225  31 16   7.3   4.0 | -19.6  -3.3  235  35 18   6.7   3.7
 25000 -17.5   0.5  225  30 16   7.3   4.0 | -17.6   0.3  230  35 18   6.7   3.7
 24000 -15.6   3.9  225  29 15   6.3   3.5 | -15.8   3.6  225  34 17   6.4   3.5
 23000 -13.7   7.3  220  27 14   6.3   3.5 | -13.9   7.0  225  32 17   6.4   3.5
 22000 -11.9  10.6  215  26 13   6.3   3.5 | -12.1  10.2  220  31 16   6.4   3.5
 21000 -10.1  13.8  210  24 12   6.1   3.3 | -10.3  13.5  220  29 15   6.0   3.3
 20000  -8.3  17.1  205  23 12   6.1   3.3 |  -8.5  16.7  215  27 14   6.1   3.3
 19500  -7.5  18.5  205  22 11   6.1   3.3 |  -7.7  18.1  215  25 13   6.1   3.3
 19000  -6.6  20.1  200  21 11   6.3   3.5 |  -6.8  19.8  215  24 12   6.1   3.4
 18500  -5.6  21.9  200  20 10   6.4   3.5 |  -5.9  21.4  210  23 12   6.1   3.4
 18000  -4.7  23.5  195  19 10   6.4   3.5 |  -5.0  23.0  210  21 11   6.1   3.4
 17500  -3.7  25.3  195  18  9   6.6   3.6 |  -4.1  24.6  205  20 10   6.1   3.4
 17000  -2.8  27.0  190  17  9   6.6   3.6 |  -3.2  26.2  205  19 10   6.1   3.4
 16500  -1.8  28.8  185  16  8   6.9   3.8 |  -2.4  27.7  200  18  9   6.2   3.4
 16000  -0.8  30.6  180  15  8   7.0   3.8 |  -1.5  29.3  195  17  9   6.3   3.4
 15500   0.2  32.4  175  13  7   7.0   3.8 |  -0.6  30.9  190  16  8   6.7   3.7
 15000   1.8  35.2  170  11  6   7.1   3.9 |   1.1  34.0  185  15  7   7.8   4.3
 14500   2.8  37.0  165  10  5   8.1   4.4 |   2.2  36.0  185  14  7   8.4   4.6
 14000   4.1  39.4  160   9  4   8.6   4.7 |   3.5  38.3  180  13  7   8.9   4.9
 13500   5.3  41.5  160   8  4   8.9   4.9 |   4.8  40.6  180  12  6   9.2   5.1
 13000   6.6  43.9  160   7  4   9.3   5.1 |   6.3  43.3  180  11  6   9.8   5.4
 12500   8.0  46.4  160   6  3   8.7   4.8 |   7.7  45.9  175  10  5   8.0   4.4
 12000   9.3  48.7  160   6  3   9.5   5.2 |   8.8  47.8  170   6  3   9.1   5.0
 11750  10.0  50.0  160   6  3   9.5   5.2 |   9.5  49.1  165   5  3   8.7   4.8
 11500  10.7  51.3  165   6  3   9.0   4.9 |  10.1  50.2  155   4  2   8.8   4.8
 11250  11.3  52.3  165   6  3   9.3   5.1 |  10.7  51.3  145   3  2   8.9   4.9
 11000  12.0  53.6  165   6  3  10.0   5.5 |  11.4  52.5  120   2  1   9.0   4.9
 10750  12.7  54.9  170   6  3   9.8   5.4 |  12.1  53.8  080   2  1   9.0   4.9
 10500  13.5  56.3  170   6  3   9.8   5.4 |  12.7  54.9  045   3  1   9.1   5.0
 10250  14.2  57.6  170   6  3   8.4   4.6 |  13.4  56.1  030   4  2   7.6   4.2
 10000  14.8  58.6  170   6  3   9.4   5.1 |  13.9  57.0  025   5  2   8.5   4.6
  9750  15.6  60.1  170   6  3  11.0   6.0 |  14.6  58.3  020   6  3  10.3   5.6
  9500  16.4  61.5  170   6  3  10.5   5.8 |  15.3  59.5  015   7  3   9.8   5.4
  9250  17.1  62.8  170   6  3   9.7   5.3 |  16.1  61.0  015   8  4   9.4   5.2
  9000  17.8  64.0  175   6  3   9.6   5.2 |  16.7  62.1  010   8  4   9.4   5.2
  8750  18.6  65.5  175   6  3  10.7   5.9 |  17.5  63.5  010   9  4  10.3   5.7
  8500  19.4  66.9  175   6  3  10.9   6.0 |  18.2  64.8  010   9  5  10.6   5.8
  8250  20.2  68.4  175   6  3  10.2   5.6 |  19.0  66.2  010   9  5   9.9   5.4
  8000  20.9  69.6  175   6  3  10.5   5.7 |  19.7  67.5  010   9  5   9.8   5.4
  7750  21.7  71.1  175   6  3   9.0   4.9 |  20.5  68.9  010   9  5   9.2   5.0
  7500  22.3  72.1  175   6  3   8.8   4.9 |  21.1  70.0  005   9  5   8.0   4.4
  7250  23.1  73.6  175   6  3  11.5   6.3 |  21.6  70.9  005   9  5   7.5   4.1
  7000  23.9  75.0  175   6  3  11.4   6.2 |  22.2  72.0  005   8  4   7.2   3.9
  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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