Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 311011
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0411 MDT Monday, August 31, 2015

This forecast is for Monday, August 31, 2015:

If the trigger temperature of 75.6 F/24.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 465 ft/min (2.4 m/s)
   Maximum height of thermals.................. 12278 ft MSL (5520 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ 1400 MDT
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9152 ft MSL (2394 ft AGL)
Thermal soaring outlook for Tuesday 09/01...... Good

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

Remarks...

Sunrise/Sunset.................... 06:26:46 / 19:32:35 MDT
Total possible sunshine........... 13 hr 5 min 49 sec (785 min 49 sec)
Altitude of sun at 12:59:14 MDT... 59.59 degrees

Upper air data from numerical model forecast valid on 08/31/2015 at 0600 MDT

Freezing level.................. 16087 ft MSL (9329 ft AGL)
Convective condensation level... 15947 ft MSL (9189 ft AGL)
Lifted condensation level....... 15169 ft MSL (8411 ft AGL)
Lifted index.................... -0.9
K index......................... +27.1

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -66.4 -87.5   265   25   13   0.6   0.3      M     M       M      M    M
 45000  -63.0 -81.4   260   29   15   5.7   3.1      M     M       M      M    M
 40000  -53.9 -65.0   240   26   14   8.3   4.6      M     M       M      M    M
 38000  -48.9 -56.0   245   25   13   8.3   4.6      M     M       M      M    M
 36000  -43.9 -47.0   245   24   12   8.4   4.6      M     M       M      M    M
 34000  -38.7 -37.7   250   23   12   8.6   4.7      M     M       M      M    M
 32000  -33.6 -28.5   250   23   12   8.5   4.7      M     M       M      M    M
 30000  -28.4 -19.1   245   22   11   7.5   4.1   41.5 106.7    12.4      M    M
 29000  -26.1 -15.0   240   22   11   7.5   4.1   40.7 105.3    11.9      M    M
 28000  -23.9 -11.0   240   22   11   7.1   3.9   39.9 103.8    11.4      M    M
 27000  -21.8  -7.2   240   22   11   7.1   3.9   38.8 101.8    10.6      M    M
 26000  -19.6  -3.3   240   22   11   7.1   3.9   37.8 100.1    10.0      M    M
 25000  -17.5   0.5   240   22   12   6.6   3.6   37.0  98.6     9.4      M    M
 24000  -15.9   3.4   240   22   11   5.3   2.9   35.3  95.6     8.0      M    M
 23000  -14.4   6.1   240   21   11   5.4   3.0   33.8  92.8     6.8      M    M
 22000  -12.8   9.0   240   20   10   5.6   3.1   32.3  90.2     5.5      M    M
 21000  -11.1  12.0   230   19   10   5.9   3.3   30.9  87.6     4.3      M    M
 20000   -9.4  15.1   225   19   10   5.9   3.3   29.6  85.2     3.1      M    M
 19500   -8.5  16.7   220   18    9   5.7   3.1   29.0  84.2     2.6      M    M
 19000   -7.5  18.5   220   18    9   8.4   4.6   28.5  83.4     2.2      M    M
 18500   -6.4  20.5   215   18    9   8.2   4.5   28.2  82.8     1.9      M    M
 18000   -5.2  22.6   215   17    9   8.5   4.6   28.0  82.4     1.6      M    M
 17500   -3.9  25.0   215   17    9   8.8   4.9   27.8  82.1     1.4      M    M
 17000   -2.7  27.1   210   17    9   8.9   4.9   27.7  81.8     1.2      M    M
 16500   -1.4  29.5   210   17    9   9.1   5.0   27.5  81.6     1.1      M    M
 16000   -0.1  31.8   215   17    9   9.1   5.0   27.4  81.4     0.9      M    M
 15500    1.3  34.3   215   17    9   9.2   5.0   27.3  81.2     0.8      M    M
 15000    2.6  36.7   220   17    9   9.2   5.1   27.2  81.0     0.7      M    M
 14500    4.6  40.3   220   16    8   9.1   5.0   27.1  80.8     0.5      M    M
 14000    6.0  42.8   225   15    8   9.2   5.0   27.0  80.6     0.4      M    M
 13500    7.3  45.1   230   14    7   9.4   5.2   26.9  80.5     0.3      M    M
 13000    8.7  47.7   235   12    6   9.5   5.2   26.9  80.4     0.2      M    M
 12500   10.1  50.2   245   11    6   7.4   4.1   26.8  80.3     0.2      M    M
 12000   11.1  52.0   255    9    5   8.0   4.4   26.4  79.5    -0.3    432  2.2
 11750   11.7  53.1   260    8    4   7.9   4.3   26.2  79.2    -0.4    407  2.1
 11500   12.2  54.0   265    8    4   7.0   3.9   26.1  78.9    -0.6    383  1.9
 11250   12.7  54.9   285    7    4   6.3   3.5   25.8  78.5    -0.8    361  1.8
 11000   13.2  55.8   300    6    3   6.7   3.7   25.6  78.0    -1.1    339  1.7
 10750   13.7  56.7   320    7    3   6.7   3.7   25.3  77.6    -1.3    317  1.6
 10500   14.2  57.6   340    7    4   6.3   3.4   25.1  77.1    -1.6    295  1.5
 10250   14.6  58.3   350    9    5   5.1   2.8   24.8  76.6    -1.9    276  1.4
 10000   15.0  59.0   355   11    5   6.4   3.5   24.4  76.0    -2.3    257  1.3
  9750   15.5  59.9   355   12    6   7.8   4.3   24.3  75.7    -2.5    234  1.2
  9500   16.0  60.8   355   13    7   7.1   3.9   24.1  75.3    -2.7    210  1.1
  9250   16.5  61.7   350   14    7   6.5   3.6   23.9  74.9    -2.9    188  1.0
  9000   17.0  62.6   350   15    8   6.3   3.5   23.6  74.5    -3.2    167  0.9
  8750   17.4  63.3   345   15    8   7.5   4.1   23.4  74.1    -3.5    146  0.7
  8500   17.9  64.2   340   16    8   5.8   3.2   23.2  73.7    -3.7    123  0.6
  8250   18.2  64.8   340   17    9   3.7   2.0   22.8  73.0    -4.1    107  0.5
  8000   18.5  65.3   335   17    9   1.9   1.0   22.3  72.1    -4.6     92  0.5
  7750   18.7  65.7   335   17    9   8.6   4.7   21.8  71.2    -5.1     78  0.4
  7500   19.2  66.6   330   17    9  -5.9  -3.2   21.6  70.8    -5.4     56  0.3
  7250   17.6  63.7   325   14    7 -27.1 -14.9   19.7  67.4    -7.3     95  0.5
  7000   16.1  61.0   320   11    6 -10.5  -5.8   17.8  64.1    -9.2    135  0.7
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/31/2015 at 0900 MDT          |       08/31/2015 at 1200 MDT
                                           |
K index... +28.4  LI... +270.2             | K index... +28.9  LI... +271.0
CAPE... +150.4  CIN... -91.7               | CAPE... +261.0  CIN... -1.7
                                           |
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 -65.5 -85.9  255  18  9   0.1   0.1 | -66.5 -87.7  235  21 11   0.5   0.3
 45000 -62.7 -80.9  245  26 14   5.8   3.2 | -63.1 -81.6  240  29 15   6.0   3.3
 40000 -53.6 -64.5  240  29 15   7.8   4.3 | -53.6 -64.5  235  29 15   8.1   4.4
 38000 -48.9 -56.0  235  26 14   7.8   4.3 | -48.8 -55.8  235  28 15   8.1   4.4
 36000 -44.2 -47.6  235  24 12   7.8   4.3 | -43.9 -47.0  240  27 14   8.1   4.4
 34000 -39.4 -38.9  235  23 12   8.1   4.4 | -38.9 -38.0  240  26 13   8.3   4.6
 32000 -33.9 -29.0  240  22 11   8.7   4.8 | -33.3 -27.9  240  25 13   9.0   4.9
 30000 -29.0 -20.2  240  22 11   8.3   4.6 | -28.5 -19.3  240  23 12   7.9   4.4
 29000 -26.5 -15.7  240  22 11   8.4   4.6 | -26.2 -15.2  240  21 11   8.0   4.4
 28000 -24.1 -11.4  240  21 11   7.0   3.8 | -23.8 -10.8  240  21 11   7.5   4.1
 27000 -22.1  -7.8  240  21 11   6.9   3.8 | -21.6  -6.9  240  21 11   7.5   4.1
 26000 -20.0  -4.0  240  21 11   6.9   3.8 | -19.4  -2.9  240  21 11   7.5   4.1
 25000 -18.0  -0.4  245  20 10   6.7   3.7 | -17.2   1.0  240  21 11   7.2   4.0
 24000 -16.2   2.8  240  20 10   5.8   3.2 | -15.3   4.5  240  22 11   6.4   3.5
 23000 -14.5   5.9  235  20 10   5.8   3.2 | -13.4   7.9  240  23 12   6.4   3.5
 22000 -12.8   9.0  235  20 11   5.6   3.1 | -11.5  11.3  240  24 12   6.2   3.4
 21000 -11.3  11.7  225  20 11   5.0   2.7 |  -9.9  14.2  230  24 12   5.7   3.1
 20000  -9.8  14.4  220  21 11   4.9   2.7 |  -8.2  17.2  225  25 13   5.7   3.1
 19500  -9.1  15.6  215  21 11   4.7   2.6 |  -7.4  18.7  225  25 13   5.7   3.1
 19000  -8.2  17.2  215  20 11   7.6   4.2 |  -6.6  20.1  220  25 13   5.7   3.1
 18500  -7.1  19.2  215  19 10   7.5   4.1 |  -5.7  21.7  220  24 12   5.7   3.1
 18000  -6.1  21.0  215  18  9   8.0   4.4 |  -4.9  23.2  220  23 12   5.8   3.2
 17500  -4.9  23.2  220  17  9   8.8   4.8 |  -4.0  24.8  220  22 11   6.1   3.4
 17000  -3.6  25.5  225  16  8   8.9   4.9 |  -3.2  26.2  220  21 11   6.1   3.4
 16500  -2.3  27.9  225  16  8   9.0   4.9 |  -2.3  27.9  220  19 10   6.2   3.4
 16000  -1.0  30.2  230  15  8   9.0   4.9 |  -1.4  29.5  225  18  9   6.2   3.4
 15500   1.0  33.8  240  15  8   9.5   5.2 |  -0.0  32.0  230  15  8   6.3   3.5
 15000   2.4  36.3  245  14  7   9.6   5.3 |   0.9  33.6  230  13  7   6.3   3.5
 14500   3.7  38.7  245  14  7   8.5   4.7 |   1.8  35.2  230  10  5   7.3   4.0
 14000   5.0  41.0  250  13  6   8.5   4.6 |   2.8  37.0  220   7  3   7.4   4.0
 13500   6.2  43.2  250  11  6   7.8   4.3 |   3.9  39.0  200   4  2   8.8   4.8
 13000   7.3  45.1  260   8  4   7.5   4.1 |   5.3  41.5  180   2  1   9.5   5.2
 12500   8.4  47.1  270   6  3   7.5   4.1 |   6.7  44.1  135   2  1   9.8   5.4
 12000   9.5  49.1  310   3  2   7.8   4.3 |   8.1  46.6  115   2  1   9.7   5.3
 11750  10.1  50.2  340   3  2   7.3   4.0 |   8.8  47.8  100   2  1   9.2   5.1
 11500  10.6  51.1  005   4  2   9.1   5.0 |   9.5  49.1  090   2  1  11.3   6.2
 11250  11.3  52.3  020   5  3   9.6   5.2 |  10.4  50.7  085   2  1  11.3   6.2
 11000  12.0  53.6  025   6  3   7.9   4.3 |  11.1  52.0  075   2  1   9.0   4.9
 10750  12.6  54.7  025   6  3   8.0   4.4 |  11.8  53.2  070   3  1   9.4   5.1
 10500  13.2  55.8  030   6  3   8.4   4.6 |  12.5  54.5  060   3  2   9.5   5.2
 10250  13.8  56.8  020   6  3   9.5   5.2 |  13.3  55.9  060   4  2   9.9   5.4
 10000  14.5  58.1  015   6  3   8.5   4.7 |  14.0  57.2  055   4  2   9.8   5.4
  9750  15.1  59.2  005   6  3   7.6   4.2 |  14.7  58.5  055   4  2   9.8   5.4
  9500  15.7  60.3  355   7  4   7.8   4.3 |  15.4  59.7  055   4  2   9.6   5.3
  9250  16.2  61.2  350   7  4   7.7   4.2 |  16.1  61.0  055   4  2   9.2   5.0
  9000  16.8  62.2  340   8  4   7.4   4.0 |  16.8  62.2  055   5  2   9.5   5.2
  8750  17.3  63.1  335  10  5   6.2   3.4 |  17.6  63.7  050   5  2  10.5   5.8
  8500  17.7  63.9  330  11  6   5.0   2.7 |  18.4  65.1  055   5  3  10.9   6.0
  8250  18.0  64.4  330  12  6   4.7   2.6 |  19.2  66.6  055   5  3  10.7   5.9
  8000  18.3  64.9  330  12  6   3.9   2.2 |  20.0  68.0  055   5  3  11.0   6.0
  7750  18.6  65.5  325  12  6   7.5   4.1 |  20.8  69.4  055   5  3  10.2   5.6
  7500  19.2  66.6  325  11  6   8.4   4.6 |  21.5  70.7  050   5  3  11.2   6.1
  7250  19.6  67.3  330  10  5   4.8   2.6 |  22.4  72.3  050   6  3  12.9   7.1
  7000  20.0  68.0  330   9  5   7.9   4.3 |  23.3  73.9  050   6  3  11.6   6.4
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/31/2015 at 1500 MDT          |       08/31/2015 at 1800 MDT
                                           |
K index... +31.3  LI... +270.6             | K index... +26.8  LI... +273.1
CAPE... +396.4  CIN... -11.2               | CAPE... +14.5  CIN... -35.2
                                           |
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 -66.5 -87.7  240  32 17  -0.2  -0.1 | -66.3 -87.3  250  32 17  -0.0  -0.0
 45000 -63.7 -82.7  250  42 21   6.4   3.5 | -63.6 -82.5  250  37 19   5.9   3.2
 40000 -53.6 -64.5  245  33 17   8.5   4.7 | -54.1 -65.4  235  22 11   8.8   4.8
 38000 -48.5 -55.3  250  30 16   8.5   4.7 | -48.8 -55.8  235  22 11   8.8   4.8
 36000 -43.4 -46.1  250  27 14   8.5   4.7 | -43.5 -46.3  235  22 12   8.8   4.8
 34000 -38.2 -36.8  245  26 13   8.6   4.7 | -38.3 -36.9  235  22 11   8.6   4.7
 32000 -32.4 -26.3  240  25 13   9.2   5.0 | -32.5 -26.5  240  21 11   9.3   5.1
 30000 -27.7 -17.9  240  24 13   7.9   4.3 | -27.8 -18.0  250  21 11   7.8   4.3
 29000 -25.4 -13.7  235  24 12   7.9   4.3 | -25.4 -13.7  250  20 10   7.9   4.3
 28000 -23.1  -9.6  235  24 12   6.7   3.7 | -23.2  -9.8  255  20 10   7.1   3.9
 27000 -21.1  -6.0  230  24 12   6.8   3.7 | -21.1  -6.0  260  20 10   7.2   3.9
 26000 -19.1  -2.4  230  24 12   6.8   3.7 | -18.9  -2.0  265  20 10   7.2   3.9
 25000 -17.2   1.0  230  24 12   6.8   3.7 | -16.8   1.8  270  20 11   7.0   3.9
 24000 -15.2   4.6  225  24 12   6.6   3.6 | -14.9   5.2  270  20 10   6.6   3.6
 23000 -13.3   8.1  225  24 12   6.6   3.6 | -13.0   8.6  270  19 10   6.6   3.6
 22000 -11.4  11.5  225  24 12   6.4   3.5 | -11.1  12.0  275  19 10   6.4   3.5
 21000  -9.6  14.7  220  22 11   5.9   3.2 |  -9.4  15.1  270  18  9   5.7   3.1
 20000  -7.9  17.8  215  20 10   5.9   3.3 |  -7.7  18.1  270  16  8   5.7   3.2
 19500  -7.1  19.2  215  19 10   6.0   3.3 |  -6.9  19.6  270  16  8   5.8   3.2
 19000  -6.3  20.7  210  18  9   5.2   2.8 |  -6.1  21.0  265  15  8   5.3   2.9
 18500  -5.5  22.1  205  16  8   5.2   2.9 |  -5.3  22.5  265  15  8   5.3   2.9
 18000  -4.8  23.4  195  15  8   5.3   2.9 |  -4.5  23.9  265  14  7   5.3   2.9
 17500  -4.0  24.8  190  13  7   5.5   3.0 |  -3.8  25.2  265  14  7   5.3   2.9
 17000  -3.2  26.2  180  13  6   5.5   3.0 |  -3.0  26.6  265  13  7   5.3   2.9
 16500  -2.4  27.7  170  12  6   5.9   3.2 |  -2.2  28.0  260  13  7   5.5   3.0
 16000  -1.5  29.3  165  11  6   5.9   3.2 |  -1.5  29.3  260  12  6   5.5   3.0
 15500  -0.3  31.5  155  10  5   6.5   3.5 |  -0.4  31.3  255  12  6   4.2   2.3
 15000   0.7  33.3  155  10  5   6.4   3.5 |   0.3  32.5  250  11  6   4.1   2.3
 14500   1.6  34.9  150   9  4   7.4   4.1 |   1.1  34.0  250  11  5   8.0   4.4
 14000   2.7  36.9  150   8  4   7.6   4.2 |   2.4  36.3  245  10  5   8.7   4.8
 13500   3.8  38.8  150   7  4   7.7   4.2 |   3.6  38.5  245   9  5   7.8   4.3
 13000   4.9  40.8  145   7  4   7.8   4.3 |   4.7  40.5  240   9  4   7.2   4.0
 12500   6.0  42.8  145   6  3   9.1   5.0 |   5.7  42.3  240   8  4   7.6   4.2
 12000   7.3  45.1  140   5  3   7.8   4.3 |   6.8  44.2  245   7  4   6.6   3.6
 11750   7.9  46.2  135   4  2   7.6   4.2 |   7.3  45.1  245   6  3   6.6   3.6
 11500   8.5  47.3  130   4  2   9.7   5.3 |   7.7  45.9  245   6  3   7.5   4.1
 11250   9.3  48.7  125   3  2  10.0   5.5 |   8.3  46.9  250   5  3   8.1   4.4
 11000   9.9  49.8  115   3  1   7.3   4.0 |   8.9  48.0  255   5  3   7.0   3.8
 10750  10.4  50.7  100   2  1   7.3   4.0 |   9.3  48.7  260   4  2   6.8   3.7
 10500  11.0  51.8  080   2  1   7.8   4.3 |   9.8  49.6  265   4  2   6.9   3.8
 10250  11.6  52.9  055   2  1   9.0   5.0 |  10.3  50.5  280   3  2   7.3   4.0
 10000  12.2  54.0  035   2  1   7.9   4.4 |  10.8  51.4  300   4  2   6.7   3.7
  9750  12.7  54.9  020   3  2   6.6   3.6 |  11.3  52.3  315   4  2   6.1   3.4
  9500  13.2  55.8  010   4  2   7.4   4.1 |  11.7  53.1  325   4  2   5.8   3.2
  9250  13.8  56.8  360   5  2   8.0   4.4 |  12.1  53.8  335   5  3   5.2   2.8
  9000  14.4  57.9  355   6  3   8.0   4.4 |  12.4  54.3  340   7  3   5.0   2.7
  8750  14.9  58.8  350   7  3   6.8   3.7 |  12.8  55.0  345   8  4   4.6   2.5
  8500  15.4  59.7  350   8  4   7.8   4.3 |  13.0  55.4  345   9  5   2.4   1.3
  8250  16.0  60.8  345   9  4   9.3   5.1 |  13.1  55.6  345  10  5   1.2   0.7
  8000  16.6  61.9  345   9  5   9.0   5.0 |  13.1  55.6  345  11  6   0.5   0.3
  7750  17.3  63.1  340  10  5   8.9   4.9 |  13.2  55.8  340  13  6   4.5   2.5
  7500  17.9  64.2  340  11  6   8.5   4.7 |  13.6  56.5  340  13  7   6.0   3.3
  7250  18.5  65.3  340  10  5   8.4   4.6 |  13.8  56.8  340  12  6   2.0   1.1
  7000  19.1  66.4  340   9  5   8.5   4.7 |  14.0  57.2  340  11  6   5.4   3.0
  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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