Soaring Guidance
Issued by NWS Denver/Boulder, CO

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

000
UXUS97 KBOU 160101
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1901 MDT Wednesday, October 15, 2014

This forecast is for Thursday, October 16, 2014:

If the trigger temperature of 69.5 F/20.8 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 353 ft/min (1.8 m/s)
   Maximum height of thermals.................. 10385 ft MSL (5098 ft AGL)

Forecast maximum temperature................... 73.0 F/23.2 C
Time of trigger temperature.................... 1145 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................. 8440 ft MSL (3153 ft AGL)
Thermal soaring outlook for Friday 10/17....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 14396 ft MSL (9109 ft AGL)
Wave soaring outlook for Friday 10/17.......... Good

Remarks... Moderate westerly flow aloft Thursday. Weak surface cold front moving
           in after 1200 MDT.

Sunrise/Sunset.................... 07:10:53 / 18:20:07 MDT
Total possible sunshine........... 11 hr 9 min 14 sec (669 min 14 sec)
Altitude of sun at 12:45:04 MDT... 41.19 degrees

Upper air data from numerical model forecast valid on 10/16/2014 at 0600 MDT

Freezing level.................. 14759 ft MSL (9472 ft AGL)
Convective condensation level... 18773 ft MSL (13486 ft AGL)
Lifted condensation level....... 15500 ft MSL (10213 ft AGL)
Lifted index.................... +5.4
K index......................... -2.5

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  -66.6 -87.9   265   62   32   1.0   0.5      M     M       M      M    M
 45000  -64.4 -83.9   265   69   36   3.1   1.7      M     M       M      M    M
 40000  -59.7 -75.5   260   69   35   5.4   3.0      M     M       M      M    M
 38000  -54.9 -66.8   260   64   33   8.0   4.4      M     M       M      M    M
 36000  -50.1 -58.2   255   60   31   8.0   4.4      M     M       M      M    M
 34000  -45.0 -49.0   260   58   30   8.7   4.8      M     M       M      M    M
 32000  -39.8 -39.6   265   57   29   8.7   4.8      M     M       M      M    M
 30000  -34.4 -29.9   270   54   28   7.7   4.2   41.3 106.3    14.0      M    M
 29000  -32.1 -25.8   265   53   27   7.7   4.2   40.5 104.9    13.6      M    M
 28000  -29.8 -21.6   265   51   26   7.6   4.2   39.8 103.6    13.2      M    M
 27000  -27.3 -17.1   260   48   25   8.2   4.5   39.1 102.4    12.8      M    M
 26000  -24.9 -12.8   250   45   23   8.2   4.5   38.5 101.3    12.5      M    M
 25000  -22.4  -8.3   245   44   23   8.2   4.5   38.0 100.4    12.2      M    M
 24000  -20.1  -4.2   240   43   22   7.3   4.0   37.3  99.1    11.7      M    M
 23000  -17.9  -0.2   240   41   21   7.3   4.0   36.3  97.4    11.1      M    M
 22000  -15.7   3.7   245   39   20   7.4   4.0   35.5  95.9    10.5      M    M
 21000  -13.6   7.5   245   36   18   6.6   3.6   34.4  94.0     9.8      M    M
 20000  -11.7  10.9   245   32   16   6.6   3.6   33.3  91.9     8.9      M    M
 19500  -10.7  12.7   245   30   15   6.5   3.6   32.8  91.0     8.5      M    M
 19000   -9.7  14.5   245   28   14   6.2   3.4   32.3  90.1     8.1      M    M
 18500   -8.8  16.2   245   25   13   5.6   3.1   31.6  88.8     7.5      M    M
 18000   -8.0  17.6   245   23   12   5.5   3.0   30.9  87.5     6.9      M    M
 17500   -7.1  19.2   245   20   10   7.0   3.8   30.2  86.4     6.4      M    M
 17000   -6.1  21.0   240   18    9   7.1   3.9   29.8  85.6     6.0      M    M
 16500   -5.0  23.0   240   15    8   7.8   4.3   29.3  84.8     5.7      M    M
 16000   -3.7  25.3   240   14    7   8.7   4.8   29.1  84.4     5.5      M    M
 15500   -1.8  28.8   240   12    6   9.1   5.0   28.9  84.0     5.3      M    M
 15000   -0.4  31.3   245   13    7   9.2   5.1   28.8  83.9     5.3      M    M
 14500    1.0  33.8   255   14    7   8.9   4.9   28.7  83.7     5.3      M    M
 14000    2.3  36.1   265   16    8   8.1   4.4   28.5  83.3     5.0      M    M
 13500    3.5  38.3   270   20   10   8.0   4.4   28.2  82.8     4.8      M    M
 13000    4.5  40.1   280   23   12   5.9   3.2   27.7  81.9     4.4      M    M
 12500    5.4  41.7   280   28   14   6.3   3.4   27.1  80.8     3.8      M    M
 12000    6.1  43.0   285   31   16   3.5   1.9   26.3  79.4     3.1      M    M
 11500    6.6  43.9   290   32   17   3.9   2.1   25.4  77.7     2.2      M    M
 11000    7.1  44.8   290   33   17   3.3   1.8   24.4  75.9     1.2      M    M
 10500    7.5  45.5   290   32   17   3.6   2.0   23.4  74.1     0.1      M    M
 10250    7.7  45.9   295   32   16   2.7   1.5   22.9  73.2    -0.4    344  1.7
 10000    7.9  46.2   295   31   16   4.0   2.2   22.3  72.2    -0.9    331  1.7
  9750    8.3  46.9   295   29   15   5.9   3.3   22.0  71.6    -1.3    312  1.6
  9500    8.7  47.7   300   27   14   5.7   3.1   21.7  71.0    -1.6    293  1.5
  9250    9.0  48.2   300   25   13   4.7   2.6   21.4  70.5    -2.0    274  1.4
  9000    9.4  48.9   300   23   12   5.1   2.8   20.9  69.7    -2.4    257  1.3
  8750    9.8  49.6   305   21   11   6.6   3.6   20.7  69.2    -2.7    236  1.2
  8500   10.3  50.5   305   19   10   6.2   3.4   20.4  68.7    -2.9    215  1.1
  8250   10.7  51.3   310   17    9   6.0   3.3   20.1  68.2    -3.2    194  1.0
  8000   11.2  52.2   315   15    8   6.2   3.4   19.8  67.7    -3.5    173  0.9
  7750   11.6  52.9   320   14    7   6.6   3.6   19.6  67.2    -3.8    151  0.8
  7500   12.1  53.8   320   12    6   6.9   3.8   19.4  66.8    -4.0    129  0.7
  7250   12.7  54.9   325   11    6   7.4   4.1   19.2  66.5    -4.2    106  0.5
  7000   13.2  55.8   330    9    5   7.4   4.1   19.0  66.2    -4.4     82  0.4
  6750   13.8  56.8   335    8    4   8.5   4.7   18.8  65.9    -4.6     57  0.3
  6500   14.4  57.9   340    7    4   3.5   1.9   18.6  65.5    -4.8     33  0.2
  6250   14.3  57.7   335    5    3  -3.2  -1.8   17.8  64.1    -5.6     28  0.1
  6000   14.2  57.6   330    4    2   4.4   2.4   17.0  62.7    -6.4     23  0.1
  5750   14.4  57.9   320    3    2  -7.9  -4.3   16.5  61.8    -6.9     10  0.0
  5500   12.0  53.6   270    2    1 -56.6 -31.0   13.5  56.3   -10.1     76  0.4

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

           10/16/2014 at 0900 MDT          |       10/16/2014 at 1200 MDT
                                           |
K index... -7.0  LI... +6.4                | K index... -3.6  LI... +4.7
CAPE... 0.0  CIN... -0.5                   | CAPE... 0.0  CIN... -0.8
                                           |
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 -64.9 -84.8  275  54 28  -0.8  -0.4 | -65.3 -85.5  265  52 27  -0.1  -0.1
 45000 -65.1 -85.2  270  76 39   3.2   1.8 | -64.7 -84.5  270  79 41   3.5   1.9
 40000 -60.3 -76.5  265  77 40   4.6   2.5 | -59.5 -75.1  270  81 42   4.2   2.3
 38000 -55.6 -68.1  265  73 37   8.1   4.4 | -55.3 -67.5  270  74 38   7.3   4.0
 36000 -50.7 -59.3  265  68 35   8.1   4.4 | -50.9 -59.6  265  66 34   7.3   4.0
 34000 -45.7 -50.3  265  64 33   8.5   4.7 | -45.5 -49.9  265  60 31   8.4   4.6
 32000 -40.0 -40.0  265  59 30   8.5   4.7 | -40.5 -40.9  270  56 29   8.4   4.6
 30000 -35.2 -31.4  265  55 29   7.8   4.3 | -35.5 -31.9  270  53 27   8.3   4.6
 29000 -32.8 -27.0  260  54 28   7.8   4.3 | -33.0 -27.4  265  53 27   8.4   4.6
 28000 -30.5 -22.9  260  52 27   7.9   4.3 | -30.5 -22.9  265  52 27   8.4   4.6
 27000 -28.2 -18.8  260  51 26   7.6   4.2 | -28.0 -18.4  265  52 27   8.2   4.5
 26000 -25.9 -14.6  255  49 25   7.6   4.2 | -25.6 -14.1  265  52 27   8.2   4.5
 25000 -23.7 -10.7  255  48 25   7.6   4.2 | -23.2  -9.8  265  52 27   8.2   4.5
 24000 -21.4  -6.5  255  46 24   7.7   4.2 | -21.0  -5.8  265  52 27   6.8   3.7
 23000 -19.1  -2.4  260  44 23   7.7   4.2 | -19.0  -2.2  270  51 26   6.7   3.7
 22000 -16.8   1.8  260  43 22   7.7   4.2 | -17.0   1.4  270  50 26   6.8   3.7
 21000 -14.6   5.7  260  40 20   6.9   3.8 | -15.2   4.6  270  47 24   5.8   3.2
 20000 -12.5   9.5  260  36 18   6.9   3.8 | -13.4   7.9  270  42 22   5.7   3.2
 19500 -11.5  11.3  260  34 17   6.9   3.8 | -12.5   9.5  270  40 20   5.8   3.2
 19000 -10.4  13.3  260  32 16   7.1   3.9 | -11.7  10.9  270  37 19   6.5   3.6
 18500  -9.3  15.3  255  30 16   7.3   4.0 | -10.5  13.1  270  35 18   8.1   4.5
 18000  -8.2  17.2  255  29 15   7.3   4.0 |  -9.2  15.4  265  33 17   8.1   4.5
 17500  -7.1  19.2  255  28 14   7.7   4.2 |  -8.0  17.6  265  31 16   8.2   4.5
 17000  -5.9  21.4  255  27 14   7.7   4.2 |  -6.7  19.9  265  30 15   8.2   4.5
 16500  -4.8  23.4  255  27 14   7.7   4.2 |  -4.9  23.2  265  28 14   7.4   4.1
 16000  -3.1  26.4  255  25 13   7.7   4.2 |  -3.8  25.2  265  27 14   7.4   4.1
 15500  -1.9  28.6  255  25 13   7.5   4.1 |  -2.6  27.3  265  26 14   7.3   4.0
 15000  -0.8  30.6  260  25 13   7.3   4.0 |  -1.6  29.1  270  26 13   7.2   3.9
 14500   0.3  32.5  265  26 13   6.9   3.8 |  -0.5  31.1  270  26 13   6.9   3.8
 14000   1.2  34.2  270  27 14   6.0   3.3 |   0.5  32.9  275  26 14   6.2   3.4
 13500   2.1  35.8  275  27 14   5.9   3.3 |   1.4  34.5  280  27 14   6.1   3.4
 13000   2.9  37.2  275  28 14   4.9   2.7 |   2.3  36.1  285  27 14   5.7   3.1
 12500   3.6  38.5  280  28 15   5.1   2.8 |   3.1  37.6  285  28 14   5.9   3.2
 12000   4.2  39.6  285  28 14   4.4   2.4 |   3.9  39.0  285  27 14   5.4   3.0
 11500   4.9  40.8  285  27 14   4.6   2.5 |   4.6  40.3  285  27 14   5.6   3.1
 11000   5.5  41.9  290  25 13   4.3   2.4 |   5.3  41.5  285  24 12   4.0   2.2
 10500   6.0  42.8  290  21 11   4.5   2.5 |   5.8  42.4  285  19 10   4.2   2.3
 10250   6.3  43.3  290  20 10   2.5   1.4 |   6.0  42.8  280  17  9   2.6   1.4
 10000   6.5  43.7  290  19 10   4.0   2.2 |   6.2  43.2  280  15  8   4.3   2.4
  9750   6.9  44.4  290  16  8   6.7   3.7 |   6.7  44.1  270  13  7   6.6   3.6
  9500   7.3  45.1  295  14  7   6.0   3.3 |   7.1  44.8  260  11  6   6.1   3.3
  9250   7.7  45.9  295  12  6   5.1   2.8 |   7.5  45.5  250  10  5   6.0   3.3
  9000   8.1  46.6  295  11  6   5.3   2.9 |   8.0  46.4  240   9  5   7.3   4.0
  8750   8.5  47.3  295   9  5   6.3   3.4 |   8.6  47.5  235   9  5   8.7   4.8
  8500   9.0  48.2  295   8  4   6.2   3.4 |   9.2  48.6  225   9  4   8.1   4.4
  8250   9.4  48.9  295   6  3   6.4   3.5 |   9.8  49.6  220   8  4   7.6   4.2
  8000   9.9  49.8  295   5  3   6.8   3.8 |  10.4  50.7  210   7  3   7.2   3.9
  7750  10.5  50.9  295   4  2   7.7   4.2 |  10.9  51.6  200   5  3   7.2   4.0
  7500  11.1  52.0  300   3  2   7.9   4.3 |  11.4  52.5  185   4  2   5.9   3.2
  7250  11.6  52.9  310   3  1   7.6   4.2 |  11.8  53.2  160   4  2   4.7   2.6
  7000  12.2  54.0  320   3  1   8.0   4.4 |  12.1  53.8  130   4  2   4.6   2.5
  6750  12.8  55.0  330   3  1   6.9   3.8 |  12.5  54.5  110   5  2   4.7   2.6
  6500  13.1  55.6  335   3  2   1.2   0.7 |  12.9  55.2  100   5  3   8.1   4.4
  6250  12.9  55.2  335   3  1  -3.4  -1.9 |  13.6  56.5  100   5  3  10.7   5.8
  6000  12.8  55.0  335   3  1   2.1   1.1 |  14.3  57.7  095   5  3   8.4   4.6
  5750  13.0  55.4  340   3  2  -3.8  -2.1 |  14.9  58.8  095   5  3  11.5   6.3
  5500  11.6  52.9  295   1  0 -27.2 -14.9 |  16.1  61.0  090   5  2  21.4  11.7

           10/16/2014 at 1500 MDT          |       10/16/2014 at 1800 MDT
                                           |
K index... +5.5  LI... +2.8                | K index... +14.6  LI... +2.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -64.2 -83.6  275  55 28  -0.7  -0.4 | -63.8 -82.8  285  47 24  -0.4  -0.2
 45000 -64.5 -84.1  275  74 38   2.7   1.5 | -63.9 -83.0  285  66 34   1.7   0.9
 40000 -60.6 -77.1  280  69 36   3.5   1.9 | -61.4 -78.5  280  71 37   3.4   1.9
 38000 -56.2 -69.2  280  64 33   7.6   4.2 | -56.3 -69.3  285  68 35   8.7   4.8
 36000 -51.6 -60.9  280  58 30   7.6   4.2 | -51.1 -60.0  285  65 33   8.7   4.8
 34000 -46.5 -51.7  280  53 27   9.1   5.0 | -45.8 -50.4  280  59 31   9.0   4.9
 32000 -40.4 -40.7  275  49 25   9.1   5.0 | -39.7 -39.5  275  52 27   9.0   4.9
 30000 -34.9 -30.8  275  48 24   9.1   5.0 | -34.5 -30.1  275  52 27   8.5   4.7
 29000 -32.2 -26.0  275  48 25   9.1   5.0 | -32.0 -25.6  270  53 27   8.5   4.7
 28000 -29.5 -21.1  275  48 25   9.3   5.1 | -29.4 -20.9  270  55 28   8.6   4.7
 27000 -27.1 -16.8  275  49 25   7.6   4.2 | -27.1 -16.8  270  55 28   7.8   4.3
 26000 -24.8 -12.6  270  51 26   7.6   4.2 | -24.7 -12.5  275  55 28   7.8   4.3
 25000 -22.5  -8.5  270  53 27   7.6   4.2 | -22.4  -8.3  275  55 28   7.8   4.3
 24000 -20.3  -4.5  270  53 27   7.2   3.9 | -20.1  -4.2  275  54 28   7.3   4.0
 23000 -18.2  -0.8  275  52 27   7.2   4.0 | -18.0  -0.4  280  53 27   7.3   4.0
 22000 -16.1   3.0  275  51 26   7.4   4.0 | -15.8   3.6  280  51 26   7.3   4.0
 21000 -14.1   6.6  275  49 25   6.2   3.4 | -14.0   6.8  280  49 25   5.6   3.1
 20000 -12.3   9.9  275  45 23   6.2   3.4 | -12.4   9.7  280  47 24   5.6   3.1
 19500 -11.4  11.5  275  43 22   6.2   3.4 | -11.6  11.1  285  45 23   5.6   3.1
 19000 -10.5  13.1  275  41 21   6.3   3.4 | -10.8  12.6  285  44 23   5.7   3.1
 18500  -9.6  14.7  275  39 20   6.4   3.5 |  -9.9  14.2  280  42 22   5.9   3.3
 18000  -8.6  16.5  275  37 19   6.3   3.5 |  -9.0  15.8  280  40 21   5.9   3.3
 17500  -7.6  18.3  275  35 18   6.9   3.8 |  -8.1  17.4  275  39 20   5.8   3.2
 17000  -6.5  20.3  275  33 17   7.0   3.8 |  -7.2  19.0  275  37 19   5.8   3.2
 16500  -5.4  22.3  275  32 16   6.7   3.7 |  -6.3  20.7  270  35 18   5.7   3.1
 16000  -4.0  24.8  275  30 16   6.2   3.4 |  -5.0  23.0  265  31 16   5.6   3.1
 15500  -3.0  26.6  275  29 15   6.0   3.3 |  -4.2  24.4  265  28 15   6.7   3.7
 15000  -2.2  28.0  275  28 14   5.8   3.2 |  -3.1  26.4  260  26 13   7.6   4.2
 14500  -1.3  29.7  270  27 14   5.9   3.3 |  -2.1  28.2  255  23 12   8.1   4.4
 14000  -0.4  31.3  270  26 13   6.4   3.5 |  -0.8  30.6  255  21 11   9.1   5.0
 13500   0.4  32.7  270  24 13   6.5   3.6 |   0.5  32.9  255  18  9   9.1   5.0
 13000   1.5  34.7  270  23 12   8.1   4.4 |   1.8  35.2  250  17  9   8.1   4.5
 12500   2.6  36.7  270  21 11   8.1   4.5 |   3.0  37.4  250  16  8   8.3   4.5
 12000   3.7  38.7  265  18 10   7.4   4.1 |   4.1  39.4  245  15  8   7.7   4.2
 11500   4.7  40.5  260  16  8   7.6   4.1 |   5.3  41.5  240  14  7   7.8   4.3
 11000   5.8  42.4  255  14  7   7.3   4.0 |   6.3  43.3  230  13  7   6.7   3.7
 10500   6.9  44.4  245  13  7   8.0   4.4 |   7.3  45.1  215  13  6   7.5   4.1
 10250   7.4  45.3  240  13  7   4.0   2.2 |   7.7  45.9  210  13  7   3.9   2.1
 10000   7.6  45.7  240  13  7   4.9   2.7 |   7.9  46.2  210  12  6   4.4   2.4
  9750   8.3  46.9  235  13  7   9.4   5.2 |   8.5  47.3  205  11  6   8.2   4.5
  9500   8.9  48.0  230  13  7   8.3   4.6 |   9.0  48.2  200  10  5   7.4   4.1
  9250   9.5  49.1  225  13  7   6.8   3.7 |   9.5  49.1  195  10  5   5.8   3.2
  9000   9.9  49.8  220  13  7   4.5   2.4 |   9.9  49.8  185   9  5   4.9   2.7
  8750  10.2  50.4  215  11  6   4.3   2.4 |  10.3  50.5  175   8  4   6.0   3.3
  8500  10.5  50.9  205  10  5   4.5   2.5 |  10.7  51.3  165   7  4   5.9   3.3
  8250  10.8  51.4  195   8  4   4.3   2.4 |  11.2  52.2  150   7  4   7.3   4.0
  8000  11.1  52.0  170   6  3   5.6   3.0 |  11.8  53.2  140   6  3   8.1   4.4
  7750  11.6  52.9  150   6  3   7.0   3.8 |  12.4  54.3  130   6  3   7.8   4.3
  7500  12.1  53.8  130   6  3   8.6   4.7 |  13.0  55.4  120   6  3   8.5   4.6
  7250  12.9  55.2  130   6  3  10.5   5.7 |  13.7  56.7  115   6  3   9.4   5.2
  7000  13.6  56.5  125   6  3  10.5   5.8 |  14.4  57.9  105   6  3   9.4   5.1
  6750  14.4  57.9  125   6  3  10.0   5.5 |  15.0  59.0  100   7  3   8.4   4.6
  6500  15.1  59.2  125   6  3  10.2   5.6 |  15.7  60.3  095   7  4   8.7   4.8
  6250  15.9  60.6  125   6  3  10.9   6.0 |  16.3  61.3  090   7  4   9.3   5.1
  6000  16.7  62.1  125   6  3   9.7   5.3 |  17.0  62.6  085   7  4   9.5   5.2
  5750  17.5  63.5  120   6  3  11.4   6.3 |  17.7  63.9  075   7  4   7.2   3.9
  5500  18.5  65.3  120   5  3  18.4  10.1 |  17.9  64.2  070   6  3   1.5   0.8
________________________________________________________________________________

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 old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 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.