Soaring Guidance
Issued by NWS Pueblo, CO

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
000
UXUS97 KPUB 241007
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0407 MDT Monday, August 24, 2015

This forecast is for Monday, August 24, 2015:

If the trigger temperature of 75.7 F/24.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1304 ft/min (6.6 m/s)
   Maximum height of thermals.................. 19934 ft MSL (13176 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13030 ft MSL (6273 ft AGL)
Thermal soaring outlook for Tuesday 08/25...... Good

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

Remarks...

Sunrise/Sunset.................... 06:20:28 / 19:42:53 MDT
Total possible sunshine........... 13 hr 22 min 26 sec (802 min 26 sec)
Altitude of sun at 13:01:17 MDT... 62.05 degrees

Upper air data from numerical model forecast valid on 08/24/2015 at 0600 MDT

Freezing level.................. 15820 ft MSL (9062 ft AGL)
Convective condensation level... 16786 ft MSL (10028 ft AGL)
Lifted condensation level....... 17359 ft MSL (10601 ft AGL)
Lifted index.................... -3.4
K index......................... +17.3

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  -65.3 -85.5   290   26   13   2.2   1.2      M     M       M      M    M
 45000  -59.9 -75.8   290   38   19   6.6   3.6      M     M       M      M    M
 40000  -49.8 -57.6   290   48   25   5.6   3.1      M     M       M      M    M
 38000  -46.4 -51.5   290   46   24   5.6   3.1      M     M       M      M    M
 36000  -43.1 -45.6   290   44   23   5.7   3.1      M     M       M      M    M
 34000  -39.3 -38.7   295   39   20   6.4   3.5      M     M       M      M    M
 32000  -35.4 -31.7   295   34   18   6.3   3.5      M     M       M      M    M
 30000  -31.2 -24.2   295   29   15   7.1   3.9   39.1 102.3     8.3      M    M
 29000  -29.1 -20.4   300   27   14   7.1   3.9   38.1 100.6     7.6      M    M
 28000  -26.5 -15.7   300   24   12   6.6   3.6   36.9  98.5     6.8      M    M
 27000  -24.5 -12.1   295   22   11   6.7   3.7   35.7  96.2     5.9      M    M
 26000  -22.5  -8.5   295   19   10   6.7   3.7   34.5  94.2     5.0      M    M
 25000  -20.5  -4.9   290   17    9   6.7   3.7   33.6  92.4     4.2      M    M
 24000  -18.6  -1.5   295   16    8   6.7   3.7   32.3  90.2     3.2      M    M
 23000  -16.6   2.1   295   14    7   6.8   3.7   31.3  88.3     2.3      M    M
 22000  -14.6   5.7   300   13    7   7.2   3.9   30.3  86.6     1.4      M    M
 21000  -12.4   9.7   305   12    6   7.4   4.0   29.4  85.0     0.7      M    M
 20000  -10.1  13.8   305   12    6   7.4   4.1   28.6  83.5     0.1      M    M
 19500   -9.0  15.8   305   11    6   7.4   4.0   28.3  82.9    -0.2   1265  6.4
 19000   -7.9  17.8   310   11    6   7.3   4.0   27.9  82.2    -0.6   1218  6.2
 18500   -6.9  19.6   320   11    6   7.3   4.0   27.4  81.4    -1.0   1171  6.0
 18000   -5.8  21.6   325   12    6   8.0   4.4   27.1  80.7    -1.4   1124  5.7
 17500   -4.6  23.7   325   12    6   8.2   4.5   26.8  80.2    -1.7   1075  5.5
 17000   -3.5  25.7   320   12    6   8.5   4.7   26.5  79.8    -2.0   1025  5.2
 16500   -2.1  28.2   320   12    6   9.5   5.2   26.4  79.6    -2.2    970  4.9
 16000   -0.8  30.6   320   11    6   9.5   5.2   26.4  79.5    -2.3    914  4.6
 15500    0.6  33.1   320   11    5   9.2   5.0   26.3  79.4    -2.4    858  4.4
 15000    2.0  35.6   325   10    5   9.2   5.0   26.2  79.2    -2.5    803  4.1
 14500    3.3  37.9   330    9    5   9.1   5.0   26.1  79.0    -2.6    747  3.8
 14000    5.4  41.7   335    9    5   9.1   5.0   26.0  78.7    -2.8    664  3.4
 13500    6.7  44.1   340    8    4   8.7   4.8   25.8  78.5    -2.9    609  3.1
 13000    8.0  46.4   345    8    4   8.9   4.9   25.7  78.2    -3.0    554  2.8
 12500    9.3  48.7   345    7    3   8.3   4.5   25.4  77.8    -3.3    503  2.6
 12000   10.6  51.1   350    6    3   9.2   5.1   25.3  77.6    -3.4    448  2.3
 11750   11.3  52.3   355    5    3   9.2   5.1   25.3  77.5    -3.5    420  2.1
 11500   12.0  53.6   360    5    2   9.4   5.2   25.3  77.5    -3.5    393  2.0
 11250   12.6  54.7   360    4    2   8.9   4.9   25.2  77.4    -3.6    366  1.9
 11000   13.2  55.8   005    4    2   8.3   4.6   25.1  77.2    -3.8    341  1.7
 10750   13.8  56.8   010    3    2   8.5   4.7   25.0  77.1    -3.9    316  1.6
 10500   14.4  57.9   015    3    2   9.3   5.1   25.0  76.9    -4.1    290  1.5
 10250   15.0  59.0   015    3    1  10.2   5.6   25.0  76.9    -4.1    263  1.3
 10000   15.7  60.3   020    2    1   8.7   4.8   25.0  76.9    -4.2    236  1.2
  9750   16.2  61.2   025    2    1   7.5   4.1   24.8  76.6    -4.4    213  1.1
  9500   16.8  62.2   025    2    1   7.6   4.2   24.6  76.4    -4.6    189  1.0
  9250   17.3  63.1   015    1    1   7.1   3.9   24.5  76.0    -4.9    167  0.8
  9000   17.8  64.0   355    1    1   7.9   4.4   24.3  75.7    -5.1    145  0.7
  8750   18.4  65.1   335    1    1   7.6   4.2   24.2  75.5    -5.3    120  0.6
  8500   18.8  65.8   315    1    1   1.7   0.9   23.8  74.8    -5.6    100  0.5
  8250   18.7  65.7   280    2    1  -3.3  -1.8   22.9  73.3    -6.5     96  0.5
  8000   18.6  65.5   265    3    2   2.5   1.4   22.1  71.8    -7.3     91  0.5
  7750   18.5  65.3   260    4    2 -15.6  -8.5   21.3  70.3    -8.1     87  0.4
  7500   16.3  61.3   265    6    3 -28.8 -15.8   18.6  65.5   -10.8    144  0.7
  7250   14.7  58.5   265    6    3 -18.4 -10.1   16.6  61.9   -12.9    186  0.9
  7000   13.0  55.4   270    6    3 -27.7 -15.2   14.6  58.3   -14.9    228  1.2
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/24/2015 at 0900 MDT          |       08/24/2015 at 1200 MDT
                                           |
K index... +13.6  LI... +272.5             | K index... +16.1  LI... +271.6
CAPE... +40.0  CIN... -59.1                | CAPE... +150.4  CIN... -34.5
                                           |
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 -65.0 -85.0  280  25 13   2.1   1.1 | -64.9 -84.8  275  27 14   2.0   1.1
 45000 -59.8 -75.6  290  37 19   6.3   3.5 | -60.0 -76.0  285  38 20   5.9   3.3
 40000 -50.1 -58.2  295  48 25   5.5   3.0 | -50.7 -59.3  295  46 24   5.9   3.3
 38000 -46.8 -52.2  295  44 23   5.5   3.0 | -47.1 -52.8  300  41 21   5.9   3.3
 36000 -43.4 -46.1  300  40 20   5.7   3.1 | -43.5 -46.3  300  37 19   6.1   3.3
 34000 -39.6 -39.3  300  35 18   6.4   3.5 | -39.7 -39.5  305  32 16   6.4   3.5
 32000 -35.8 -32.4  305  30 16   6.3   3.4 | -35.9 -32.6  310  27 14   6.4   3.5
 30000 -31.4 -24.5  305  27 14   7.4   4.1 | -31.1 -24.0  315  24 13   8.1   4.5
 29000 -29.2 -20.6  305  25 13   7.4   4.1 | -28.7 -19.7  315  23 12   8.1   4.5
 28000 -27.0 -16.6  305  24 12   7.4   4.0 | -26.3 -15.3  315  22 11   7.5   4.1
 27000 -24.8 -12.6  305  22 12   7.3   4.0 | -24.1 -11.4  315  21 11   7.3   4.0
 26000 -22.1  -7.8  300  21 11   7.4   4.0 | -21.4  -6.5  315  19 10   7.3   4.0
 25000 -19.9  -3.8  300  20 10   6.5   3.6 | -19.2  -2.6  315  18  9   6.2   3.4
 24000 -18.1  -0.6  300  19 10   6.2   3.4 | -17.5   0.5  310  19 10   5.9   3.3
 23000 -16.3   2.7  295  17  9   6.3   3.4 | -15.8   3.6  305  19 10   6.0   3.3
 22000 -14.4   6.1  295  16  8   7.0   3.8 | -14.0   6.8  305  20 10   6.8   3.8
 21000 -12.3   9.9  300  15  8   7.1   3.9 | -11.9  10.6  300  19 10   6.9   3.8
 20000 -10.1  13.8  300  14  7   7.1   3.9 |  -9.9  14.2  300  19 10   7.0   3.8
 19500  -9.1  15.6  305  14  7   7.2   3.9 |  -8.9  16.0  295  19 10   7.6   4.2
 19000  -8.0  17.6  310  14  7   7.3   4.0 |  -7.7  18.1  295  18  9   8.4   4.6
 18500  -6.9  19.6  310  14  7   7.2   3.9 |  -6.4  20.5  295  17  9   8.4   4.6
 18000  -5.8  21.6  315  14  7   8.5   4.6 |  -5.2  22.6  295  16  8   8.2   4.5
 17500  -4.5  23.9  315  13  7   8.5   4.7 |  -4.0  24.8  295  15  8   8.2   4.5
 17000  -3.3  26.1  315  13  6   8.8   4.8 |  -2.8  27.0  295  14  7   8.4   4.6
 16500  -2.0  28.4  315  12  6   9.1   5.0 |  -1.6  29.1  300  13  6   8.5   4.6
 16000  -0.7  30.7  320  12  6   9.1   5.0 |  -0.3  31.5  300  12  6   8.5   4.7
 15500   0.7  33.3  320  12  6   9.3   5.1 |   1.0  33.8  305  11  6   8.7   4.8
 15000   2.1  35.8  320  11  6   9.3   5.1 |   2.3  36.1  310  10  5   8.7   4.8
 14500   3.5  38.3  325  11  6   8.9   4.9 |   3.6  38.5  320  10  5   8.8   4.8
 14000   4.8  40.6  330  11  5   8.9   4.9 |   4.9  40.8  325   9  5   8.8   4.9
 13500   6.2  43.2  330  10  5   9.2   5.0 |   6.2  43.2  330   9  5   8.8   4.8
 13000   7.6  45.7  335  10  5   9.2   5.0 |   7.5  45.5  335   9  5   8.8   4.8
 12500   8.9  48.0  335  10  5   7.5   4.1 |   8.9  48.0  340   9  5   8.3   4.6
 12000  10.2  50.4  340   9  5  10.2   5.6 |  10.1  50.2  340   8  4   9.6   5.3
 11750  10.9  51.6  340   9  5   9.6   5.3 |  10.8  51.4  345   8  4   9.4   5.1
 11500  11.6  52.9  340   9  4   9.5   5.2 |  11.5  52.7  345   8  4   9.4   5.2
 11250  12.3  54.1  345   8  4   9.0   4.9 |  12.2  54.0  345   7  4   9.4   5.2
 11000  12.9  55.2  345   8  4   9.0   4.9 |  12.9  55.2  345   7  4   9.4   5.2
 10750  13.6  56.5  345   7  4   9.1   5.0 |  13.6  56.5  345   7  3   9.5   5.2
 10500  14.3  57.7  345   7  4   8.9   4.9 |  14.3  57.7  345   6  3   9.4   5.1
 10250  14.9  58.8  345   6  3   8.7   4.8 |  15.0  59.0  345   6  3   9.2   5.1
 10000  16.1  61.0  345   5  3   7.8   4.3 |  16.3  61.3  345   5  2   9.1   5.0
  9750  16.6  61.9  350   4  2   7.1   3.9 |  17.0  62.6  345   4  2   9.1   5.0
  9500  17.1  62.8  345   3  2   6.9   3.8 |  17.6  63.7  345   4  2   9.3   5.1
  9250  17.5  63.5  340   3  1   6.6   3.6 |  18.2  64.8  340   3  2   9.3   5.1
  9000  17.9  64.2  335   2  1   7.8   4.3 |  18.9  66.0  335   2  1   9.6   5.3
  8750  18.4  65.1  330   1  1   5.3   2.9 |  19.6  67.3  340   2  1   9.8   5.4
  8500  18.6  65.5  300   1  1   2.0   1.1 |  20.3  68.5  340   2  1   9.7   5.3
  8250  18.7  65.7  275   2  1   1.1   0.6 |  21.0  69.8  340   1  1   9.8   5.4
  8000  18.8  65.8  260   2  1   5.2   2.9 |  21.7  71.1  340   1  0   9.6   5.3
  7750  19.4  66.9  255   3  2   9.6   5.2 |  22.5  72.5  000   0  0  15.2   8.3
  7500  19.9  67.8  245   3  2   4.4   2.4 |  24.0  75.2  000   0  0  24.8  13.6
  7250  20.3  68.5  235   3  1  17.6   9.7 |  25.5  77.9  145   1  0   7.7   4.2
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/24/2015 at 1500 MDT          |       08/24/2015 at 1800 MDT
                                           |
K index... +24.4  LI... +271.7             | K index... +26.1  LI... +272.0
CAPE... +125.5  CIN... -22.1               | CAPE... +104.7  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 -65.0 -85.0  275  30 15   1.8   1.0 | -65.5 -85.9  280  34 17   1.8   1.0
 45000 -60.3 -76.5  285  39 20   5.9   3.3 | -61.0 -77.8  285  41 21   5.7   3.1
 40000 -51.0 -59.8  295  48 25   6.0   3.3 | -51.9 -61.4  295  50 26   6.3   3.4
 38000 -47.4 -53.3  300  45 23   6.0   3.3 | -48.1 -54.6  300  45 23   6.3   3.4
 36000 -43.8 -46.8  305  42 21   6.2   3.4 | -44.3 -47.7  305  41 21   6.7   3.7
 34000 -39.8 -39.6  305  34 17   6.7   3.7 | -39.8 -39.6  305  36 19   7.6   4.2
 32000 -35.8 -32.4  305  26 13   6.5   3.5 | -35.3 -31.5  310  31 16   7.9   4.3
 30000 -31.0 -23.8  315  23 12   8.1   4.4 | -30.7 -23.3  310  27 14   7.7   4.2
 29000 -28.0 -18.4  320  21 11   8.1   4.4 | -28.4 -19.1  310  24 13   7.7   4.2
 28000 -25.7 -14.3  325  21 11   7.4   4.0 | -25.5 -13.9  315  22 11   8.0   4.4
 27000 -23.4 -10.1  325  20 10   7.4   4.1 | -23.1  -9.6  315  21 11   8.0   4.4
 26000 -21.2  -6.2  325  19 10   7.4   4.1 | -20.7  -5.3  320  21 11   8.0   4.4
 25000 -19.0  -2.2  325  18  9   6.2   3.4 | -18.4  -1.1  325  21 11   6.2   3.4
 24000 -17.4   0.7  320  20 10   5.7   3.1 | -16.7   1.9  325  22 11   5.6   3.1
 23000 -15.7   3.7  320  21 11   5.8   3.2 | -15.1   4.8  325  23 12   5.7   3.1
 22000 -14.0   6.8  320  23 12   7.0   3.8 | -13.4   7.9  325  25 13   7.0   3.9
 21000 -11.8  10.8  315  23 12   7.4   4.0 | -11.3  11.7  325  24 12   7.3   4.0
 20000  -9.7  14.5  315  24 12   7.5   4.1 |  -9.2  15.4  325  23 12   7.4   4.1
 19500  -8.6  16.5  315  24 12   7.9   4.3 |  -8.1  17.4  325  23 12   7.7   4.2
 19000  -7.4  18.7  315  23 12   8.7   4.8 |  -6.9  19.6  325  22 11   8.3   4.5
 18500  -6.2  20.8  315  22 11   8.7   4.8 |  -5.8  21.6  330  21 11   8.3   4.5
 18000  -4.9  23.2  315  20 10   8.5   4.7 |  -4.6  23.7  330  19 10   8.0   4.4
 17500  -3.7  25.3  315  18  9   8.5   4.6 |  -3.4  25.9  335  17  9   8.0   4.4
 17000  -2.5  27.5  320  16  8   8.2   4.5 |  -2.3  27.9  345  15  8   7.9   4.3
 16500  -1.4  29.5  325  13  7   7.6   4.2 |  -1.1  30.0  355  13  7   7.7   4.2
 16000  -0.3  31.5  335  10  5   7.5   4.1 |  -0.0  32.0  010  11  6   7.6   4.2
 15500   0.9  33.6  345   8  4   8.6   4.7 |   1.2  34.2  020  10  5   8.9   4.9
 15000   2.2  36.0  355   7  4   8.5   4.7 |   2.4  36.3  030   9  4   8.7   4.8
 14500   4.1  39.4  010   6  3   9.3   5.1 |   3.7  38.7  040   8  4   9.3   5.1
 14000   5.5  41.9  015   5  3   9.2   5.1 |   5.8  42.4  050   7  4   9.5   5.2
 13500   6.8  44.2  020   5  3   9.4   5.2 |   7.2  45.0  055   7  4   9.4   5.1
 13000   8.2  46.8  025   5  2   9.5   5.2 |   8.6  47.5  060   7  4   9.5   5.2
 12500   9.6  49.3  030   4  2   9.1   5.0 |  10.0  50.0  070   6  3   8.8   4.8
 12000  11.0  51.8  035   4  2   9.7   5.3 |  11.3  52.3  075   6  3   9.3   5.1
 11750  11.7  53.1  040   4  2   9.7   5.3 |  12.0  53.6  080   6  3   9.3   5.1
 11500  12.5  54.5  045   4  2   9.5   5.2 |  12.7  54.9  085   6  3   9.1   5.0
 11250  13.2  55.8  050   3  2   9.5   5.2 |  13.4  56.1  095   5  3   8.6   4.7
 11000  13.9  57.0  055   3  2   9.6   5.3 |  14.0  57.2  100   5  3   8.3   4.5
 10750  14.6  58.3  060   3  2   9.6   5.3 |  14.6  58.3  110   5  3   8.4   4.6
 10500  15.3  59.5  065   3  2  10.1   5.5 |  15.3  59.5  115   5  2   8.9   4.9
 10250  16.1  61.0  075   3  1  10.3   5.7 |  16.0  60.8  125   5  2   9.2   5.1
 10000  16.8  62.2  085   3  1   9.3   5.1 |  16.6  61.9  140   5  2   8.4   4.6
  9750  17.5  63.5  090   3  1   8.9   4.9 |  17.2  63.0  145   5  3   8.0   4.4
  9500  18.1  64.6  095   3  1  10.0   5.5 |  17.8  64.0  155   6  3   8.7   4.8
  9250  18.9  66.0  100   3  1  10.5   5.8 |  18.5  65.3  155   6  3   9.1   5.0
  9000  19.7  67.5  105   3  1  10.0   5.5 |  19.1  66.4  160   6  3   8.9   4.9
  8750  20.4  68.7  105   3  2   9.5   5.2 |  19.8  67.6  165   6  3   9.1   5.0
  8500  21.1  70.0  110   3  2  10.1   5.6 |  20.5  68.9  165   6  3   9.8   5.4
  8250  21.9  71.4  110   3  2  10.7   5.8 |  21.3  70.3  165   7  3  10.1   5.5
  8000  22.7  72.9  115   3  2  10.2   5.6 |  22.0  71.6  170   7  3  10.3   5.6
  7750  23.5  74.3  120   3  2  11.5   6.3 |  22.7  72.9  170   7  3   9.2   5.1
  7500  24.3  75.7  115   3  2  12.0   6.6 |  23.3  73.9  170   7  3   7.5   4.1
  7250  25.1  77.2  120   3  2  10.8   5.9 |  23.8  74.8  165   6  3   7.3   4.0
  7000  25.9  78.6  120   4  2  11.8   6.5 |  24.3  75.7  165   6  3   7.4   4.0
  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


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.