Soaring Guidance
Issued by NWS Pueblo, 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

000
UXUS97 KPUB 221033
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0433 MDT Monday, September 22, 2014

This forecast is for Monday, September 22, 2014:

If the trigger temperature of 68.6 F/20.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 158 ft/min (0.8 m/s)
   Maximum height of thermals.................. 11424 ft MSL (4255 ft AGL)

Forecast maximum temperature................... 69.0 F/21.0 C
Time of trigger temperature.................... 1415 MDT
Time of overdevelopment........................ 1400 MDT
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9654 ft MSL (2485 ft AGL)
Thermal soaring outlook for Tuesday 09/23...... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Increasing
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 27626 ft MSL (20457 ft AGL)
Wave soaring outlook for Tuesday 09/23......... Poor

Remarks...

Sunrise/Sunset.................... 06:46:43 / 18:57:29 MDT
Total possible sunshine........... 12 hr 10 min 47 sec (730 min 47 sec)
Altitude of sun at 12:51:37 MDT... 51.18 degrees

Upper air data from numerical model forecast valid on 09/22/2014 at 0600 MDT

Freezing level.................. 14961 ft MSL (7792 ft AGL)
Convective condensation level... 12852 ft MSL (5683 ft AGL)
Lifted condensation level....... 12389 ft MSL (5220 ft AGL)
Lifted index.................... -1.3
K index......................... +30.1

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  -66.0 -86.8   285   35   18   3.0   1.7      M     M       M      M    M
 45000  -60.0 -76.0   280   52   27   5.4   3.0      M     M       M      M    M
 40000  -51.8 -61.2   275   59   31   6.0   3.3      M     M       M      M    M
 38000  -48.2 -54.8   275   56   29   6.0   3.3      M     M       M      M    M
 36000  -44.6 -48.3   275   52   27   5.9   3.2      M     M       M      M    M
 34000  -40.7 -41.3   275   43   22   6.7   3.7      M     M       M      M    M
 32000  -36.7 -34.1   275   34   18   6.5   3.5      M     M       M      M    M
 30000  -31.5 -24.7   270   34   17   9.1   5.0   38.9 102.1    14.2      M    M
 29000  -28.7 -19.7   270   35   18   9.1   5.0   38.7 101.7    14.3      M    M
 28000  -26.0 -14.8   270   36   18   8.5   4.6   38.7 101.6    14.3      M    M
 27000  -23.1  -9.6   265   32   16   7.7   4.2   37.6  99.6    13.7      M    M
 26000  -20.8  -5.4   260   29   15   7.7   4.2   36.8  98.3    13.2      M    M
 25000  -18.5  -1.3   255   26   13   7.2   4.0   36.2  97.2    12.8      M    M
 24000  -16.7   1.9   250   24   12   6.4   3.5   34.9  94.8    11.8      M    M
 23000  -14.8   5.4   245   22   11   6.5   3.6   33.7  92.7    10.8      M    M
 22000  -13.0   8.6   235   21   11   6.6   3.6   32.7  90.9     9.9      M    M
 21000  -11.1  12.0   235   21   11   6.5   3.6   31.5  88.6     8.9      M    M
 20000   -9.2  15.4   230   22   11   6.6   3.6   30.4  86.7     8.0      M    M
 19500   -8.2  17.2   230   22   11   6.6   3.6   29.9  85.8     7.5      M    M
 19000   -7.4  18.7   230   22   11   6.0   3.3   29.3  84.7     7.0      M    M
 18500   -6.5  20.3   225   22   11   6.0   3.3   28.6  83.6     6.5      M    M
 18000   -5.6  21.9   225   22   11   6.3   3.5   28.0  82.5     5.9      M    M
 17500   -4.7  23.5   225   22   11   6.5   3.6   27.5  81.4     5.4      M    M
 17000   -3.8  25.2   225   23   12   6.5   3.6   26.9  80.5     4.9      M    M
 16500   -2.8  27.0   225   23   12   6.2   3.4   26.4  79.4     4.4      M    M
 16000   -1.9  28.6   230   23   12   6.3   3.4   25.8  78.4     3.8      M    M
 15500   -1.0  30.2   230   23   12   6.1   3.3   25.2  77.4     3.3      M    M
 15000   -0.2  31.6   230   24   12   6.1   3.4   24.6  76.3     2.7      M    M
 14500    0.7  33.3   235   24   13   7.2   4.0   24.0  75.2     2.2      M    M
 14000    1.9  35.4   235   24   13   8.2   4.5   23.8  74.8     1.9      M    M
 13500    3.2  37.8   235   24   12   8.1   4.5   23.6  74.4     1.7      M    M
 13000    4.3  39.7   235   25   13   7.5   4.1   23.2  73.8     1.4      M    M
 12500    5.4  41.7   235   27   14   7.1   3.9   22.9  73.2     1.0      M    M
 12000    6.3  43.3   235   28   15   7.3   4.0   22.4  72.4     0.5      M    M
 11750    6.9  44.4   235   29   15   7.6   4.2   22.2  72.0     0.3      M    M
 11500    7.4  45.3   235   30   15   7.5   4.1   22.1  71.7     0.1      M    M
 11250    7.9  46.2   235   30   16   7.4   4.0   21.9  71.4    -0.1    352  1.8
 11000    8.4  47.1   230   30   16   6.6   3.6   21.7  71.1    -0.3    330  1.7
 10750    8.9  48.0   230   31   16   6.1   3.3   21.4  70.6    -0.6    310  1.6
 10500    9.3  48.7   230   31   16   6.0   3.3   21.1  70.0    -0.9    290  1.5
 10250    9.7  49.5   230   31   16   3.9   2.2   20.8  69.4    -1.3    271  1.4
 10000   10.0  50.0   225   29   15   2.2   1.2   19.7  67.5    -2.4    246  1.3
  9750   10.1  50.2   225   28   14   1.0   0.6   19.1  66.3    -3.1    237  1.2
  9500   10.1  50.2   225   27   14   0.2   0.1   18.4  65.1    -3.8    229  1.2
  9250   10.1  50.2   220   26   13  -0.6  -0.3   17.6  63.7    -4.5    222  1.1
  9000   10.0  50.0   215   25   13   0.2   0.1   16.8  62.3    -5.3    216  1.1
  8750   10.0  50.0   215   25   13  -0.3  -0.2   16.1  61.0    -6.0    208  1.1
  8500    9.9  49.8   210   23   12  -3.0  -1.6   15.2  59.4    -6.9    204  1.0
  8250    9.7  49.5   205   21   11  -3.8  -2.1   14.2  57.6    -7.9    204  1.0
  8000    9.5  49.1   200   19   10  -3.6  -2.0   13.2  55.8    -8.9    203  1.0
  7750    9.3  48.7   190   17    9   0.4   0.2   12.3  54.2    -9.7    200  1.0
  7500    9.6  49.3   185   13    7   7.3   4.0   11.9  53.4   -10.2    184  0.9
  7250    9.9  49.8   180    9    5  -5.4  -3.0   11.5  52.6   -10.7    168  0.9
  7000      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

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

           09/22/2014 at 0900 MDT          |       09/22/2014 at 1200 MDT
                                           |
K index... +29.5  LI... -2.4               | K index... +23.8  LI... -2.0
CAPE... +263.1  CIN... -39.1               | CAPE... +229.3  CIN... -40.6
                                           |
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 -65.3 -85.5  295  30 16   3.4   1.8 | -65.0 -85.0  290  26 14   3.5   1.9
 45000 -59.2 -74.6  280  46 24   5.0   2.8 | -58.7 -73.7  285  41 21   5.2   2.9
 40000 -51.5 -60.7  270  54 28   5.7   3.1 | -51.0 -59.8  275  52 27   4.6   2.5
 38000 -48.1 -54.6  265  54 28   5.7   3.1 | -48.2 -54.8  270  51 26   4.6   2.5
 36000 -44.3 -47.7  265  54 28   5.8   3.2 | -45.5 -49.9  265  50 26   4.4   2.4
 34000 -40.5 -40.9  260  48 25   6.3   3.5 | -41.1 -42.0  265  45 23   7.9   4.3
 32000 -36.7 -34.1  260  42 22   6.0   3.3 | -35.7 -32.3  260  40 21   8.5   4.7
 30000 -31.6 -24.9  255  38 20   8.9   4.9 | -30.9 -23.6  260  38 19   8.2   4.5
 29000 -29.0 -20.2  255  37 19   8.9   4.9 | -28.4 -19.1  260  37 19   8.2   4.5
 28000 -26.3 -15.3  255  36 18   8.3   4.6 | -26.0 -14.8  260  36 18   7.5   4.1
 27000 -23.9 -11.0  250  34 18   8.0   4.4 | -23.8 -10.8  255  35 18   7.4   4.0
 26000 -21.5  -6.7  250  33 17   8.0   4.4 | -21.7  -7.1  255  35 18   7.4   4.1
 25000 -19.1  -2.4  245  31 16   8.1   4.4 | -19.5  -3.1  250  34 18   7.3   4.0
 24000 -17.0   1.4  245  29 15   6.8   3.7 | -17.5   0.5  245  35 18   6.6   3.6
 23000 -15.1   4.8  235  28 14   6.9   3.8 | -15.6   3.9  240  36 19   6.6   3.6
 22000 -12.6   9.3  230  26 13   5.8   3.2 | -13.6   7.5  235  38 19   6.4   3.5
 21000 -11.2  11.8  230  26 14   5.1   2.8 | -11.9  10.6  235  36 18   6.0   3.3
 20000  -9.8  14.4  230  27 14   5.3   2.9 | -10.1  13.8  235  33 17   6.0   3.3
 19500  -9.1  15.6  230  27 14   5.5   3.0 |  -9.3  15.3  240  32 16   5.9   3.3
 19000  -8.2  17.2  230  27 14   6.5   3.6 |  -8.4  16.9  240  31 16   6.4   3.5
 18500  -7.3  18.9  230  28 14   6.4   3.5 |  -7.4  18.7  240  29 15   6.4   3.5
 18000  -6.3  20.7  230  28 14   7.2   3.9 |  -6.5  20.3  245  27 14   6.3   3.5
 17500  -5.2  22.6  230  28 14   7.4   4.1 |  -5.6  21.9  245  25 13   6.2   3.4
 17000  -4.2  24.4  230  28 14   7.3   4.0 |  -4.7  23.5  245  23 12   6.2   3.4
 16500  -3.2  26.2  235  27 14   6.4   3.5 |  -3.7  25.3  245  21 11   6.6   3.6
 16000  -2.2  28.0  235  26 14   6.4   3.5 |  -2.8  27.0  250  19 10   6.6   3.6
 15500  -1.2  29.8  235  26 13   7.4   4.1 |  -1.2  29.8  255  17  9   7.7   4.2
 15000  -0.1  31.8  240  26 13   7.5   4.1 |  -0.1  31.8  260  16  8   7.6   4.1
 14500   1.0  33.8  240  25 13   7.7   4.2 |   1.0  33.8  265  17  9   7.8   4.3
 14000   2.1  35.8  245  26 14   7.8   4.3 |   2.2  36.0  270  17  9   7.8   4.3
 13500   3.3  37.9  245  27 14   7.5   4.1 |   3.3  37.9  270  18  9   7.5   4.1
 13000   4.3  39.7  245  27 14   6.8   3.8 |   4.4  39.9  270  18 10   7.4   4.0
 12500   5.2  41.4  245  27 14   6.4   3.5 |   5.5  41.9  270  19 10   6.7   3.7
 12000   6.2  43.2  240  26 14   7.6   4.1 |   6.4  43.5  265  20 10   7.0   3.8
 11750   6.7  44.1  240  26 13   7.5   4.1 |   6.9  44.4  265  20 10   7.0   3.8
 11500   7.2  45.0  240  25 13   7.4   4.1 |   7.4  45.3  260  20 10   6.6   3.6
 11250   7.7  45.9  240  24 12   6.4   3.5 |   7.8  46.0  255  20 10   6.5   3.6
 11000   8.1  46.6  240  23 12   6.7   3.7 |   8.3  46.9  250  20 10   7.3   4.0
 10750   8.7  47.7  235  22 11   7.7   4.2 |   8.8  47.8  245  20 10   7.5   4.1
 10500   9.2  48.6  235  21 11   7.5   4.1 |   9.3  48.7  245  20 10   7.5   4.1
 10250   9.7  49.5  235  20 10   7.4   4.1 |   9.7  49.5  240  20 10   7.6   4.1
 10000  10.3  50.5  235  21 11   7.3   4.0 |  10.2  50.4  240  20 10   7.3   4.0
  9750  10.8  51.4  235  22 11   6.6   3.6 |  10.8  51.4  235  19 10   7.5   4.1
  9500  11.2  52.2  235  22 11   4.9   2.7 |  11.3  52.3  235  19 10   5.3   2.9
  9250  11.5  52.7  230  21 11   0.5   0.3 |  11.5  52.7  230  18  9   3.0   1.7
  9000  11.5  52.7  225  21 11   1.9   1.1 |  11.7  53.1  225  18  9   4.1   2.3
  8750  11.6  52.9  225  20 10   0.3   0.2 |  12.1  53.8  220  17  9   9.2   5.0
  8500  11.4  52.5  220  19 10  -3.4  -1.9 |  12.9  55.2  210  16  8   8.0   4.4
  8250  11.1  52.0  215  17  9  -5.1  -2.8 |  13.2  55.8  205  15  8   4.1   2.3
  8000  10.8  51.4  205  15  8  -1.7  -0.9 |  13.5  56.3  200  14  7   4.2   2.3
  7750  10.9  51.6  195  14  7   4.3   2.4 |  13.9  57.0  190  13  7   7.8   4.3
  7500  11.3  52.3  185  12  6   4.8   2.6 |  14.6  58.3  185  13  7  11.3   6.2
  7250  11.6  52.9  180   9  5   5.5   3.0 |  15.4  59.7  185  13  7   9.5   5.2
  7000     M     M    M   M  M     M     M |  16.1  61.0  185  13  6  11.2   6.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/22/2014 at 1500 MDT          |       09/22/2014 at 1800 MDT
                                           |
K index... +26.7  LI... -3.2               | K index... +26.9  LI... -2.2
CAPE... +611.2  CIN... -5.8                | CAPE... +462.1  CIN... -23.0
                                           |
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  285  29 15   3.8   2.1 | -64.6 -84.3  290  30 15   3.5   1.9
 45000 -58.7 -73.7  285  43 22   4.6   2.5 | -58.4 -73.1  285  43 22   5.0   2.8
 40000 -51.7 -61.1  280  51 26   5.4   3.0 | -50.7 -59.3  280  48 25   5.7   3.1
 38000 -48.4 -55.1  270  48 25   5.4   3.0 | -47.3 -53.1  275  42 22   5.7   3.1
 36000 -45.1 -49.2  265  45 23   5.2   2.9 | -43.9 -47.0  270  37 19   5.7   3.1
 34000 -40.6 -41.1  260  41 21   8.1   4.4 | -40.1 -40.2  265  36 18   6.3   3.5
 32000 -35.1 -31.2  250  36 19   8.7   4.8 | -36.3 -33.3  260  35 18   6.4   3.5
 30000 -30.4 -22.7  250  36 19   8.0   4.4 | -31.3 -24.3  260  34 18   7.9   4.3
 29000 -28.0 -18.4  250  36 19   8.1   4.4 | -28.9 -20.0  265  33 17   7.9   4.3
 28000 -25.6 -14.1  250  36 19   7.4   4.1 | -26.6 -15.9  265  33 17   8.0   4.4
 27000 -23.5 -10.3  250  36 18   7.2   4.0 | -24.2 -11.6  270  34 18   8.1   4.4
 26000 -21.3  -6.3  250  35 18   7.2   4.0 | -21.8  -7.2  270  36 19   8.1   4.4
 25000 -19.2  -2.6  250  34 18   7.2   4.0 | -19.4  -2.9  275  38 19   8.1   4.4
 24000 -17.2   1.0  255  33 17   6.7   3.7 | -17.1   1.2  275  39 20   7.7   4.2
 23000 -15.3   4.5  255  33 17   6.7   3.7 | -14.8   5.4  275  39 20   7.7   4.2
 22000 -13.3   8.1  260  32 17   6.6   3.6 | -12.5   9.5  275  40 21   7.4   4.1
 21000 -11.4  11.5  260  31 16   6.2   3.4 | -10.7  12.7  275  40 21   5.6   3.1
 20000  -9.6  14.7  265  30 16   6.2   3.4 |  -9.1  15.6  275  41 21   5.7   3.1
 19500  -8.7  16.3  270  30 15   6.2   3.4 |  -8.3  17.1  275  41 21   5.7   3.1
 19000  -7.8  18.0  270  31 16   6.2   3.4 |  -7.5  18.5  275  41 21   5.6   3.1
 18500  -6.9  19.6  270  33 17   6.2   3.4 |  -6.6  20.1  275  41 21   5.7   3.1
 18000  -6.0  21.2  275  35 18   6.2   3.4 |  -5.8  21.6  280  41 21   5.7   3.1
 17500  -5.1  22.8  275  34 17   5.9   3.3 |  -5.0  23.0  280  40 20   6.0   3.3
 17000  -4.2  24.4  275  32 16   5.9   3.2 |  -4.2  24.4  280  38 20   6.1   3.3
 16500  -3.4  25.9  275  31 16   6.5   3.6 |  -3.3  26.1  285  36 19   5.9   3.2
 16000  -2.4  27.7  275  30 15   6.5   3.6 |  -2.5  27.5  280  33 17   6.0   3.3
 15500  -1.0  30.2  270  28 14   6.9   3.8 |  -1.7  28.9  280  30 16   6.7   3.7
 15000   0.0  32.0  270  26 13   6.8   3.7 |  -0.2  31.6  275  26 13   7.5   4.1
 14500   1.0  33.8  265  24 12   7.4   4.0 |   0.9  33.6  275  23 12   7.8   4.3
 14000   2.1  35.8  265  22 11   7.5   4.1 |   2.0  35.6  270  21 11   7.9   4.3
 13500   3.2  37.8  260  20 10   7.1   3.9 |   3.1  37.6  270  19 10   8.3   4.5
 13000   4.2  39.6  255  19 10   6.9   3.8 |   4.4  39.9  265  18  9   8.5   4.6
 12500   5.1  41.2  250  18  9   6.4   3.5 |   5.6  42.1  260  17  9   6.6   3.6
 12000   6.1  43.0  240  17  9   7.3   4.0 |   6.6  43.9  250  16  8   8.8   4.8
 11750   6.6  43.9  240  17  9   7.2   3.9 |   7.2  45.0  245  15  8   8.4   4.6
 11500   7.1  44.8  235  17  9   7.1   3.9 |   7.8  46.0  240  15  8   7.9   4.3
 11250   7.6  45.7  230  16  8   7.4   4.0 |   8.3  46.9  230  15  8   6.5   3.6
 11000   8.1  46.6  225  16  8   7.9   4.3 |   8.8  47.8  225  15  8   6.2   3.4
 10750   8.7  47.7  225  16  8   8.1   4.4 |   9.2  48.6  215  15  8   6.2   3.4
 10500   9.2  48.6  220  16  8   7.8   4.3 |   9.6  49.3  210  15  8   6.7   3.7
 10250   9.7  49.5  215  16  8   7.2   3.9 |  10.2  50.4  205  16  8   7.9   4.3
 10000  10.2  50.4  210  16  8   7.8   4.3 |  10.7  51.3  200  16  8   7.9   4.3
  9750  10.8  51.4  205  16  8   8.5   4.6 |  11.3  52.3  195  17  9   7.6   4.2
  9500  11.4  52.5  200  17  9   8.2   4.5 |  11.9  53.4  190  18  9   7.7   4.2
  9250  11.9  53.4  195  16  8   7.9   4.3 |  12.4  54.3  185  18  9   7.7   4.2
  9000  12.5  54.5  190  16  8   8.1   4.5 |  13.0  55.4  185  18  9   7.9   4.4
  8750  13.1  55.6  190  16  8   9.2   5.0 |  13.6  56.5  180  18  9   9.0   4.9
  8500  13.8  56.8  185  16  8  10.3   5.7 |  14.3  57.7  175  18 10   9.9   5.4
  8250  14.6  58.3  185  16  8  10.7   5.9 |  15.0  59.0  175  18  9   9.8   5.4
  8000  15.4  59.7  185  16  8  10.3   5.6 |  15.7  60.3  175  18  9  10.1   5.5
  7750  16.2  61.2  185  16  8  11.7   6.4 |  16.5  61.7  175  18  9   9.2   5.0
  7500  17.1  62.8  180  16  8  11.2   6.1 |  17.0  62.6  170  17  9   6.2   3.4
  7250  17.8  64.0  180  15  8   9.0   5.0 |  17.4  63.3  170  16  8   4.8   2.6
  7000  18.5  65.3  180  14  7  10.8   5.9 |  17.8  64.0  170  14  7   5.8   3.2
  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.