Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 221020
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0420 MDT Saturday, August 22, 2015

This forecast is for Saturday, August 22, 2015:

If the trigger temperature of 78.8 F/26.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1546 ft/min (7.9 m/s)
   Maximum height of thermals.................. 21805 ft MSL (15047 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................. 12256 ft MSL (5498 ft AGL)
Thermal soaring outlook for Sunday 08/23....... Good

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

Remarks...

Sunrise/Sunset.................... 06:18:39 / 19:45:43 MDT
Total possible sunshine........... 13 hr 27 min 4 sec (807 min 4 sec)
Altitude of sun at 13:01:48 MDT... 62.73 degrees

Upper air data from numerical model forecast valid on 08/22/2015 at 0600 MDT

Freezing level.................. 16098 ft MSL (9340 ft AGL)
Convective condensation level... 18656 ft MSL (11898 ft AGL)
Lifted condensation level....... 19156 ft MSL (12398 ft AGL)
Lifted index.................... -3.3
K index......................... +22.5

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  -62.9 -81.2   280   41   21   2.3   1.3      M     M       M      M    M
 45000  -58.4 -73.1   280   53   27   4.9   2.7      M     M       M      M    M
 40000  -50.9 -59.6   290   57   29   3.7   2.0      M     M       M      M    M
 38000  -48.7 -55.7   290   51   26   3.7   2.0      M     M       M      M    M
 36000  -46.5 -51.7   290   46   23   3.8   2.1      M     M       M      M    M
 34000  -42.8 -45.0   295   40   21   6.9   3.8      M     M       M      M    M
 32000  -38.7 -37.7   295   36   18   6.9   3.8      M     M       M      M    M
 30000  -34.1 -29.4   300   30   15   8.0   4.4   35.4  95.8     4.6      M    M
 29000  -31.1 -24.0   300   26   14   8.0   4.4   34.6  94.3     4.0      M    M
 28000  -28.8 -19.8   300   23   12   7.9   4.3   34.1  93.3     3.6      M    M
 27000  -26.4 -15.5   300   21   11   7.9   4.3   33.2  91.8     3.0      M    M
 26000  -24.0 -11.2   300   19   10   7.9   4.3   32.5  90.6     2.5      M    M
 25000  -21.7  -7.1   300   17    9   7.9   4.3   32.0  89.5     2.0      M    M
 24000  -19.4  -2.9   300   16    8   7.7   4.2   31.2  88.1     1.3      M    M
 23000  -17.1   1.2   300   16    8   7.7   4.2   30.4  86.8     0.7      M    M
 22000  -14.9   5.2   295   15    8   7.8   4.3   29.8  85.6     0.1      M    M
 21000  -12.6   9.3   290   14    7   7.9   4.4   29.1  84.3    -0.6   1467  7.5
 20000  -10.3  13.5   285   14    7   8.0   4.4   28.5  83.2    -1.2   1368  7.0
 19500   -9.1  15.6   280   13    7   8.1   4.4   28.2  82.8    -1.5   1319  6.7
 19000   -7.9  17.8   280   13    7   8.3   4.5   28.0  82.3    -1.8   1269  6.4
 18500   -6.7  19.9   280   12    6   8.3   4.6   27.7  81.8    -2.0   1219  6.2
 18000   -5.6  21.9   275   11    6   8.6   4.7   27.5  81.4    -2.3   1168  5.9
 17500   -4.2  24.4   280   11    6   9.5   5.2   27.4  81.3    -2.4   1112  5.7
 17000   -2.8  27.0   280   12    6   9.5   5.2   27.3  81.2    -2.5   1055  5.4
 16500   -1.4  29.5   280   12    6   9.2   5.1   27.3  81.1    -2.6    999  5.1
 16000   -0.0  32.0   280   12    6   9.2   5.1   27.2  80.9    -2.7    943  4.8
 15500    1.4  34.5   280   12    6   9.5   5.2   27.1  80.8    -2.8    887  4.5
 15000    2.8  37.0   280   12    6   9.8   5.4   27.1  80.8    -2.8    829  4.2
 14500    5.0  41.0   280   12    6   9.5   5.2   27.1  80.8    -2.8    741  3.8
 14000    6.4  43.5   275   13    6   9.4   5.2   27.0  80.6    -2.9    685  3.5
 13500    7.8  46.0   275   13    7   9.9   5.4   27.0  80.6    -3.0    628  3.2
 13000    9.3  48.7   275   13    7  10.5   5.8   27.1  80.7    -2.9    567  2.9
 12500   10.8  51.4   275   13    6   8.0   4.4   27.1  80.8    -2.9    508  2.6
 12000   12.1  53.8   275   13    7   9.7   5.3   26.9  80.4    -3.1    455  2.3
 11750   12.8  55.0   275   13    7   9.5   5.2   26.9  80.4    -3.1    427  2.2
 11500   13.5  56.3   275   13    7   9.1   5.0   26.9  80.4    -3.2    398  2.0
 11250   14.1  57.4   275   13    7   8.9   4.9   26.8  80.2    -3.3    372  1.9
 11000   14.8  58.6   275   14    7   9.4   5.2   26.8  80.2    -3.3    343  1.7
 10750   15.5  59.9   275   14    7   9.3   5.1   26.7  80.1    -3.3    315  1.6
 10500   16.2  61.2   275   14    7   9.3   5.1   26.7  80.0    -3.4    287  1.5
 10250   16.9  62.4   275   14    7   8.2   4.5   26.6  79.9    -3.5    260  1.3
 10000   17.5  63.5   275   14    7   8.4   4.6   26.5  79.7    -3.6    235  1.2
  9750   18.1  64.6   275   15    8   9.1   5.0   26.4  79.6    -3.7    208  1.1
  9500   18.8  65.8   280   15    8   8.8   4.8   26.4  79.5    -3.8    181  0.9
  9250   19.4  66.9   280   16    8   8.2   4.5   26.3  79.3    -3.9    154  0.8
  9000   20.0  68.0   280   17    9   7.3   4.0   26.1  79.0    -4.1    130  0.7
  8750   20.5  68.9   280   19   10   7.0   3.8   25.9  78.7    -4.3    108  0.5
  8500   20.9  69.6   280   20   10   5.2   2.8   25.7  78.2    -4.6     87  0.4
  8250   21.1  70.0   280   22   11  -0.6  -0.3   25.1  77.2    -5.1     74  0.4
  8000   20.8  69.4   280   23   12  -5.0  -2.7   24.1  75.5    -6.2     75  0.4
  7750   20.6  69.1   280   24   13   0.7   0.4   23.2  73.7    -7.2     75  0.4
  7500   20.6  69.1   280   23   12  -6.1  -3.4   22.5  72.4    -7.9     68  0.3
  7250   19.3  66.7   280   19   10 -25.2 -13.8   20.8  69.4    -9.6     99  0.5
  7000   17.2  63.0   280   15    8 -27.7 -15.2   18.4  65.1   -12.0    155  0.8
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/22/2015 at 0900 MDT          |       08/22/2015 at 1200 MDT
                                           |
K index... +22.5  LI... +272.5             | K index... +24.8  LI... +270.5
CAPE... +120.0  CIN... -92.9               | CAPE... +710.4  CIN... -10.2
                                           |
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 -62.1 -79.8  285  40 21   1.4   0.8 | -62.1 -79.8  280  39 20   1.0   0.5
 45000 -58.9 -74.0  290  56 29   3.7   2.0 | -59.4 -74.9  290  54 28   3.6   1.9
 40000 -53.1 -63.6  295  50 26   5.4   3.4 | -53.7 -64.7  300  45 23   6.1   3.3
 38000 -49.9 -57.8  300  47 24   5.3   2.9 | -50.1 -58.2  305  43 22   6.1   3.3
 36000 -46.7 -52.1  310  45 23   5.3   2.9 | -46.5 -51.7  310  42 21   6.0   3.3
 34000 -42.4 -44.3  310  41 21   7.6   4.2 | -42.1 -43.8  305  39 20   7.5   4.1
 32000 -37.9 -36.2  305  36 19   7.6   4.2 | -37.7 -35.9  305  36 18   7.5   4.1
 30000 -32.6 -26.7  300  31 16   7.9   4.3 | -32.4 -26.3  300  34 17   7.9   4.3
 29000 -30.3 -22.5  300  29 15   7.9   4.3 | -30.1 -22.2  300  33 17   8.0   4.4
 28000 -28.0 -18.4  295  27 14   7.7   4.2 | -27.7 -17.9  300  33 17   8.1   4.4
 27000 -25.7 -14.3  290  24 12   7.6   4.2 | -25.3 -13.5  295  31 16   8.2   4.5
 26000 -23.4 -10.1  285  21 11   7.6   4.2 | -22.9  -9.2  290  30 15   8.2   4.5
 25000 -21.2  -6.2  280  18  9   7.5   4.1 | -20.4  -4.7  290  28 15   7.9   4.4
 24000 -19.1  -2.4  270  17  9   6.8   3.7 | -18.5  -1.3  285  26 14   6.3   3.4
 23000 -17.1   1.2  265  16  8   6.9   3.8 | -16.7   1.9  275  25 13   6.3   3.5
 22000 -15.1   4.8  255  16  8   7.2   4.0 | -14.8   5.4  270  23 12   6.9   3.8
 21000 -12.8   9.0  250  15  7   8.1   4.5 | -12.5   9.5  265  22 11   8.2   4.5
 20000 -10.4  13.3  245  13  7   8.2   4.5 | -10.1  13.8  260  21 11   8.2   4.5
 19500  -9.2  15.4  240  13  7   8.1   4.4 |  -8.9  16.0  260  20 10   8.1   4.4
 19000  -8.0  17.6  240  12  6   9.2   5.0 |  -7.6  18.3  260  20 10   8.9   4.9
 18500  -6.6  20.1  240  12  6   9.2   5.0 |  -6.3  20.7  260  20 10   8.9   4.9
 18000  -5.3  22.5  245  11  6   9.2   5.0 |  -5.0  23.0  260  20 10   8.7   4.8
 17500  -3.9  25.0  245  11  5   9.2   5.1 |  -3.7  25.3  260  19 10   8.5   4.7
 17000  -2.5  27.5  245  10  5   9.2   5.1 |  -2.4  27.7  260  17  9   8.4   4.6
 16500  -1.2  29.8  250  10  5   9.4   5.2 |  -1.1  30.0  260  17  9   9.4   5.2
 16000   0.2  32.4  255   9  5   9.4   5.2 |   0.3  32.5  265  16  8   9.4   5.1
 15500   1.6  34.9  260   9  5   9.4   5.1 |   1.7  35.1  265  15  8   9.8   5.4
 15000   3.7  38.7  260   9  5   9.3   5.1 |   3.9  39.0  275  16  8  10.2   5.6
 14500   5.1  41.2  265   9  5   9.0   4.9 |   5.4  41.7  280  16  8   8.7   4.8
 14000   6.4  43.5  275  10  5   9.0   4.9 |   6.6  43.9  280  16  8   8.6   4.7
 13500   7.7  45.9  285  11  5   9.3   5.1 |   7.9  46.2  285  17  9   8.9   4.9
 13000   9.1  48.4  285  11  6   9.6   5.3 |   9.2  48.6  285  17  9   9.3   5.1
 12500  10.5  50.9  290  12  6   8.2   4.5 |  10.4  50.7  280  18  9   7.8   4.3
 12000  11.8  53.2  290  14  7   9.2   5.1 |  11.6  52.9  280  16  8   9.2   5.0
 11750  12.5  54.5  295  15  8   9.3   5.1 |  12.2  54.0  280  16  8   8.8   4.9
 11500  13.1  55.6  295  16  8   8.4   4.6 |  12.8  55.0  280  15  8   9.7   5.3
 11250  13.7  56.7  295  17  9   8.0   4.4 |  13.5  56.3  280  14  7  10.1   5.5
 11000  14.4  57.9  295  17  9   8.6   4.7 |  14.3  57.7  280  14  7   9.6   5.3
 10750  15.0  59.0  295  18  9   8.5   4.7 |  15.0  59.0  285  14  7   9.8   5.4
 10500  15.6  60.1  295  19 10   8.3   4.5 |  15.7  60.3  285  14  7   9.5   5.2
 10250  16.2  61.2  295  19 10   7.2   3.9 |  16.4  61.5  285  13  7   9.2   5.0
 10000  16.7  62.1  295  20 10   7.7   4.2 |  17.1  62.8  285  13  7   9.7   5.3
  9750  17.4  63.3  295  21 11   8.7   4.8 |  17.8  64.0  285  13  7  10.3   5.7
  9500  18.0  64.4  295  21 11   8.3   4.5 |  18.6  65.5  285  13  7  10.0   5.5
  9250  18.6  65.5  295  22 11   7.6   4.2 |  19.3  66.7  285  13  7   9.6   5.2
  9000  19.1  66.4  295  23 12   7.0   3.9 |  20.0  68.0  285  13  6   9.7   5.3
  8750  19.6  67.3  290  24 12   7.0   3.8 |  20.8  69.4  285  12  6  10.6   5.8
  8500  20.1  68.2  290  25 13   6.2   3.4 |  21.6  70.9  285  12  6  10.6   5.8
  8250  20.4  68.7  290  24 12   5.0   2.7 |  22.4  72.3  285  12  6  10.1   5.6
  8000  20.7  69.3  290  23 12   3.9   2.1 |  23.1  73.6  285  12  6  10.1   5.6
  7750  21.0  69.8  285  22 11   6.4   3.5 |  23.9  75.0  285  11  6   9.8   5.4
  7500  21.6  70.9  285  19 10   6.8   3.8 |  24.6  76.3  285  11  6  11.1   6.1
  7250  21.9  71.4  285  16  8   3.8   2.1 |  25.5  77.9  285  11  5  13.0   7.1
  7000  22.1  71.8  285  14  7   5.0   2.7 |  26.4  79.5  285  10  5  12.4   6.8
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/22/2015 at 1500 MDT          |       08/22/2015 at 1800 MDT
                                           |
K index... +32.4  LI... +269.8             | K index... +31.2  LI... +269.9
CAPE... +706.7  CIN... -0.8                | CAPE... +773.8  CIN... -32.6
                                           |
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 -63.4 -82.1  275  44 23   1.6   0.9 | -64.2 -83.6  285  47 24   1.4   0.7
 45000 -60.0 -76.0  290  53 27   3.5   1.9 | -60.8 -77.4  295  53 27   3.9   2.1
 40000 -54.2 -65.6  295  39 20   6.7   3.7 | -54.4 -65.9  295  35 18   7.4   4.1
 38000 -50.1 -58.2  295  38 20   6.8   3.7 | -49.8 -57.6  290  33 17   7.5   4.1
 36000 -46.0 -50.8  295  38 19   6.7   3.7 | -45.3 -49.5  285  32 16   7.5   4.1
 34000 -41.4 -42.5  295  37 19   7.9   4.3 | -40.6 -41.1  290  31 16   8.0   4.4
 32000 -36.7 -34.1  300  35 18   7.8   4.3 | -35.8 -32.4  290  31 16   7.9   4.3
 30000 -31.3 -24.3  300  33 17   8.0   4.4 | -30.3 -22.5  300  30 16   8.1   4.4
 29000 -28.9 -20.0  300  33 17   8.0   4.4 | -27.9 -18.2  305  30 16   8.1   4.4
 28000 -26.5 -15.7  300  32 16   7.8   4.3 | -25.5 -13.9  310  30 16   7.9   4.3
 27000 -24.2 -11.6  295  30 15   7.8   4.3 | -23.2  -9.8  310  30 16   7.9   4.3
 26000 -21.9  -7.4  295  28 14   7.8   4.3 | -20.8  -5.4  305  30 15   7.9   4.3
 25000 -19.5  -3.1  290  26 13   7.4   4.1 | -18.5  -1.3  305  30 15   7.2   4.0
 24000 -17.7   0.1  285  26 13   6.1   3.4 | -16.8   1.8  300  28 14   5.5   3.0
 23000 -15.9   3.4  280  26 13   6.2   3.4 | -15.2   4.6  290  27 14   5.6   3.1
 22000 -14.1   6.6  280  26 13   6.6   3.6 | -13.7   7.3  280  26 14   6.4   3.5
 21000 -12.0  10.4  280  25 13   7.3   4.0 | -11.5  11.3  280  25 13   7.7   4.2
 20000  -9.9  14.2  285  23 12   7.3   4.0 |  -9.3  15.3  285  24 12   7.8   4.3
 19500  -8.9  16.0  290  23 12   7.3   4.0 |  -8.1  17.4  290  23 12   7.8   4.3
 19000  -7.8  18.0  290  21 11   8.5   4.6 |  -7.1  19.2  290  22 11   7.4   4.1
 18500  -6.6  20.1  295  18  9   8.4   4.6 |  -6.0  21.2  290  20 10   7.5   4.1
 18000  -5.4  22.3  295  15  8   8.6   4.7 |  -4.9  23.2  290  19 10   7.5   4.1
 17500  -4.1  24.6  295  14  7   8.8   4.8 |  -3.8  25.2  290  16  8   7.4   4.1
 17000  -2.8  27.0  295  12  6   8.7   4.8 |  -2.8  27.0  290  12  6   7.3   4.0
 16500  -1.4  29.5  295  11  5  10.4   5.7 |  -1.6  29.1  295  10  5   8.5   4.7
 16000   0.1  32.2  295  10  5  10.2   5.6 |  -0.4  31.3  295   7  4   8.4   4.6
 15500   1.6  34.9  295  10  5  10.1   5.5 |   0.8  33.4  305   6  3   9.4   5.2
 15000   3.8  38.8  295   9  5  10.1   5.5 |   3.0  37.4  310   4  2   9.9   5.4
 14500   5.3  41.5  300   9  4   9.9   5.4 |   4.5  40.1  315   4  2   9.6   5.2
 14000   6.8  44.2  300   8  4   9.9   5.4 |   5.9  42.6  320   3  2   9.5   5.2
 13500   8.2  46.8  300   8  4  10.3   5.6 |   7.3  45.1  330   2  1   9.7   5.3
 13000   9.8  49.6  295   8  4  10.7   5.9 |   8.8  47.8  350   2  1   9.9   5.4
 12500  11.3  52.3  300   8  4   8.8   4.8 |  10.2  50.4  020   2  1   8.5   4.6
 12000  12.7  54.9  300   7  4   9.8   5.4 |  11.4  52.5  060   3  1   9.0   4.9
 11750  13.4  56.1  300   7  4   9.7   5.3 |  12.1  53.8  070   3  2   8.6   4.7
 11500  14.1  57.4  300   7  3  10.1   5.5 |  12.7  54.9  075   4  2   9.7   5.3
 11250  14.9  58.8  295   7  3  10.1   5.5 |  13.4  56.1  080   5  3   9.3   5.1
 11000  15.6  60.1  295   6  3   9.7   5.3 |  14.0  57.2  080   7  3   7.8   4.3
 10750  16.4  61.5  295   6  3   9.9   5.4 |  14.6  58.3  080   8  4   8.3   4.6
 10500  17.1  62.8  295   6  3   9.4   5.2 |  15.2  59.4  080  10  5   7.8   4.3
 10250  17.8  64.0  295   6  3   8.7   4.8 |  15.7  60.3  080  11  6   6.9   3.8
 10000  18.4  65.1  295   5  3   9.8   5.4 |  16.3  61.3  080  12  6   8.0   4.4
  9750  19.2  66.6  295   5  3  10.8   5.9 |  16.9  62.4  075  12  6   9.1   5.0
  9500  20.0  68.0  295   5  3  10.3   5.6 |  17.6  63.7  075  13  7   8.3   4.6
  9250  20.7  69.3  295   5  2   9.4   5.2 |  18.1  64.6  075  14  7   7.3   4.0
  9000  21.4  70.5  290   4  2   9.5   5.2 |  18.6  65.5  070  14  7   7.5   4.1
  8750  22.2  72.0  290   4  2  10.4   5.7 |  19.3  66.7  070  14  7   9.2   5.0
  8500  23.0  73.4  295   4  2  10.6   5.8 |  19.9  67.8  070  15  8   8.7   4.8
  8250  23.7  74.7  290   4  2  10.4   5.7 |  20.5  68.9  070  14  7   7.5   4.1
  8000  24.5  76.1  290   4  2  10.8   5.9 |  21.0  69.8  070  14  7   6.6   3.6
  7750  25.3  77.5  290   3  2   9.3   5.1 |  21.5  70.7  070  13  7  10.0   5.5
  7500  25.9  78.6  290   3  2   9.3   5.1 |  22.3  72.1  070  13  7   7.6   4.2
  7250  26.7  80.1  290   3  1  11.7   6.4 |  22.4  72.3  070  11  6   1.1   0.6
  7000  27.5  81.5  295   3  1  10.8   5.9 |  22.5  72.5  070  10  5   6.1   3.3
  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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