Soaring Guidance
Issued by NWS Pueblo, CO

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
000
UXUS97 KPUB 191051
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0451 MDT Sunday, April 19, 2015

This forecast is for Sunday, April 19, 2015:

If the trigger temperature of 38.9 F/3.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 188 ft/min (1.0 m/s)
   Maximum height of thermals.................. 11985 ft MSL (5227 ft AGL)

Forecast maximum temperature................... 44.0 F/7.1 C
Time of trigger temperature.................... 1315 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10584 ft MSL (3827 ft AGL)
Thermal soaring outlook for Monday 04/20....... Good

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

Remarks...

Sunrise/Sunset.................... 06:17:07 / 19:38:55 MDT
Total possible sunshine........... 13 hr 21 min 48 sec (801 min 48 sec)
Altitude of sun at 12:58:11 MDT... 62.31 degrees

Upper air data from numerical model forecast valid on 04/19/2015 at 0600 MDT

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 10156 ft MSL (3398 ft AGL)
Lifted condensation level....... 11286 ft MSL (4528 ft AGL)
Lifted index.................... +1.3
K index......................... +10.4

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  -55.8 -68.4   270   10    5   2.4   1.3      M     M       M      M    M
 45000  -52.2 -62.0   300   20   11   2.4   1.3      M     M       M      M    M
 40000  -48.5 -55.3   305   25   13   2.4   1.3      M     M       M      M    M
 38000  -48.5 -55.3   315   27   14  -3.1  -1.7      M     M       M      M    M
 36000  -50.3 -58.5   335   32   16  -3.1  -1.7      M     M       M      M    M
 34000  -52.2 -62.0   350   39   20  -0.3  -0.2      M     M       M      M    M
 32000  -50.1 -58.2   350   42   22   3.6   2.0      M     M       M      M    M
 30000  -48.0 -54.4   350   45   23   5.0   2.8   22.5  72.5    12.1      M    M
 29000  -46.2 -51.2   350   38   20   6.0   3.3   20.9  69.6    11.0      M    M
 28000  -43.9 -47.0   350   29   15   6.0   3.3   19.1  66.4     9.7      M    M
 27000  -42.1 -43.8   350   22   11   6.3   3.4   17.8  64.1     8.8      M    M
 26000  -39.5 -39.1   355   21   11   9.3   5.1   17.4  63.2     8.6      M    M
 25000  -36.7 -34.1   355   21   11   9.3   5.1   17.2  62.9     8.5      M    M
 24000  -34.0 -29.2   360   21   11   9.3   5.1   17.1  62.7     8.6      M    M
 23000  -31.3 -24.3   360   21   11   8.6   4.7   16.7  62.0     8.3      M    M
 22000  -28.8 -19.8   360   20   10   8.6   4.7   16.3  61.3     8.1      M    M
 21000  -26.2 -15.2   360   20   10   8.6   4.7   15.9  60.7     7.9      M    M
 20000  -23.6 -10.5   355   19   10   8.7   4.8   15.5  59.9     7.6      M    M
 19500  -22.3  -8.1   355   19   10   8.7   4.8   15.3  59.5     7.4      M    M
 19000  -21.1  -6.0   355   18    9   8.7   4.7   15.1  59.2     7.3      M    M
 18500  -19.8  -3.6   350   18    9   8.4   4.6   15.0  59.0     7.2      M    M
 18000  -18.7  -1.7   350   18    9   7.0   3.9   14.6  58.3     6.9      M    M
 17500  -17.6   0.3   350   18    9   7.0   3.8   14.2  57.5     6.5      M    M
 17000  -16.5   2.3   350   19   10   8.7   4.8   13.8  56.9     6.3      M    M
 16500  -15.1   4.8   350   20   10   8.8   4.8   13.7  56.6     6.2      M    M
 16000  -13.8   7.2   350   21   11   8.0   4.4   13.5  56.4     6.1      M    M
 15500  -12.8   9.0   350   24   12   7.2   3.9   13.1  55.6     5.7      M    M
 15000  -11.7  10.9   350   27   14   6.8   3.8   12.7  54.8     5.3      M    M
 14500  -10.8  12.6   350   29   15   5.0   2.8   12.0  53.6     4.7      M    M
 14000   -9.7  14.5   350   34   17   4.4   2.4   10.9  51.6     3.7      M    M
 13500   -9.2  15.4   355   36   18   3.8   2.1    9.9  49.8     2.8      M    M
 13000   -8.6  16.5   355   38   19   3.7   2.0    9.0  48.1     1.9      M    M
 12500   -8.2  17.2   355   39   20   3.8   2.1    8.0  46.3     0.9      M    M
 12000   -7.8  18.0   360   41   21   2.2   1.2    6.9  44.4    -0.2    385  2.0
 11750   -7.6  18.3   360   42   22   2.5   1.4    6.3  43.4    -0.7    373  1.9
 11500   -7.5  18.5   360   42   22   2.7   1.5    5.7  42.3    -1.3    360  1.8
 11250   -7.3  18.9   005   43   22   2.3   1.3    5.2  41.3    -1.9    348  1.8
 11000   -7.1  19.2   005   44   22   3.6   2.0    4.6  40.3    -2.4    335  1.7
 10750   -6.8  19.8   005   45   23   5.0   2.8    4.2  39.6    -2.8    318  1.6
 10500   -6.4  20.5   005   45   23   4.8   2.7    3.8  38.9    -3.2    300  1.5
 10250   -6.1  21.0   010   45   23   4.8   2.6    3.5  38.3    -3.6    282  1.4
 10000   -5.7  21.7   010   45   23   5.5   3.0    3.1  37.6    -4.0    264  1.3
  9750   -5.3  22.5   010   46   24   5.7   3.1    2.8  37.1    -4.3    244  1.2
  9500   -4.9  23.2   005   46   24   5.2   2.8    2.5  36.4    -4.7    225  1.1
  9250   -4.5  23.9   005   46   24   5.4   3.0    2.1  35.8    -5.0    206  1.0
  9000   -4.2  24.4   005   46   24   5.0   2.7    1.8  35.2    -5.4    187  1.0
  8750   -3.8  25.2   360   45   23   6.1   3.4    1.4  34.6    -5.7    169  0.9
  8500   -3.3  26.1   360   44   22   7.1   3.9    1.2  34.2    -6.0    146  0.7
  8250   -2.8  27.0   355   42   22   7.2   4.0    1.0  33.8    -6.2    124  0.6
  8000   -2.2  28.0   355   40   20   7.8   4.3    0.9  33.5    -6.4    100  0.5
  7750   -1.7  28.9   350   37   19   7.9   4.3    0.7  33.3    -6.6     75  0.4
  7500   -1.1  30.0   350   33   17   7.5   4.1    0.6  33.0    -6.8     51  0.3
  7250   -0.6  30.9   350   29   15   5.3   2.9    0.5  32.9    -6.9     29  0.1
  7000   -0.3  31.5   350   26   13   3.0   1.6    0.6  33.1    -6.8     13  0.1
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           04/19/2015 at 0900 MDT          |       04/19/2015 at 1200 MDT
                                           |
K index... +4.3  LI... +276.3              | K index... +4.2  LI... +276.7
CAPE... 0.0  CIN... -0.8                   | 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 -56.4 -69.5  265  15  8   2.4   1.3 | -56.3 -69.3  270  18  9   2.1   1.2
 45000 -52.8 -63.0  290  18  9   2.4   1.3 | -53.1 -63.6  280  23 12   2.1   1.2
 40000 -48.8 -55.8  305  25 13   2.5   1.4 | -49.6 -57.3  280  25 13   2.2   1.2
 38000 -48.7 -55.7  310  26 14  -2.7  -1.5 | -49.5 -57.1  290  25 13  -2.4  -1.3
 36000 -50.3 -58.5  320  27 14  -2.7  -1.5 | -51.0 -59.8  300  23 12  -2.4  -1.3
 34000 -51.9 -61.4  330  29 15   0.4   0.2 | -52.3 -62.1  315  23 12   1.2   0.7
 32000 -50.0 -58.0  335  29 15   3.2   1.7 | -50.1 -58.2  330  25 13   3.8   2.1
 30000 -48.0 -54.4  340  29 15   5.5   3.0 | -47.7 -53.9  345  28 14   6.1   3.4
 29000 -46.0 -50.8  340  26 13   6.7   3.7 | -45.6 -50.1  340  28 15   7.0   3.9
 28000 -43.5 -46.3  335  22 12   6.7   3.7 | -43.5 -46.3  340  28 15   7.1   3.9
 27000 -41.5 -42.7  330  19 10   7.0   3.8 | -40.9 -41.6  340  28 15   7.3   4.0
 26000 -39.0 -38.2  330  19 10   8.8   4.8 | -38.4 -37.1  340  28 14   8.3   4.5
 25000 -36.3 -33.3  330  19 10   8.8   4.8 | -35.9 -32.6  335  28 14   8.3   4.5
 24000 -33.7 -28.7  330  19 10   8.9   4.9 | -33.5 -28.3  335  27 14   8.3   4.5
 23000 -31.2 -24.2  325  18  9   8.1   4.5 | -30.9 -23.6  335  27 14   8.5   4.6
 22000 -28.8 -19.8  325  17  9   8.1   4.5 | -28.4 -19.1  330  26 13   8.5   4.6
 21000 -26.4 -15.5  325  16  8   8.2   4.5 | -25.9 -14.6  330  26 13   8.3   4.5
 20000 -23.9 -11.0  320  17  9   8.2   4.5 | -23.5 -10.3  325  26 13   8.0   4.4
 19500 -22.7  -8.9  320  17  9   8.2   4.5 | -22.3  -8.1  325  26 14   8.0   4.4
 19000 -21.5  -6.7  320  18  9   8.2   4.5 | -21.1  -6.0  325  27 14   8.0   4.4
 18500 -20.2  -4.4  320  18  9   7.9   4.4 | -19.9  -3.8  325  27 14   7.4   4.0
 18000 -19.1  -2.4  325  19 10   7.2   3.9 | -19.0  -2.2  325  29 15   5.6   3.1
 17500 -18.1  -0.6  330  21 11   7.3   4.0 | -18.1  -0.6  325  31 16   5.7   3.2
 17000 -17.0   1.4  330  23 12   6.4   3.5 | -17.3   0.9  325  33 17   5.7   3.1
 16500 -16.1   3.0  335  26 13   6.4   3.5 | -16.5   2.3  325  35 18   5.7   3.1
 16000 -15.2   4.6  335  29 15   7.0   3.8 | -15.6   3.9  330  37 19   5.6   3.1
 15500 -14.1   6.6  335  30 16   7.4   4.0 | -14.8   5.4  330  37 19   5.6   3.1
 15000 -13.0   8.6  340  32 17   7.0   3.9 | -14.0   6.8  330  37 19   5.9   3.2
 14500 -12.1  10.2  340  33 17   5.7   3.1 | -13.1   8.4  325  37 19   6.6   3.6
 14000 -10.9  12.4  345  33 17   3.9   2.1 | -11.7  10.9  325  36 19   6.2   3.4
 13500 -10.5  13.1  345  32 16   2.9   1.6 | -10.9  12.4  330  34 18   5.9   3.3
 13000 -10.1  13.8  350  31 16   2.3   1.2 | -10.0  14.0  330  32 16   4.9   2.7
 12500  -9.9  14.2  355  32 16   2.4   1.3 |  -9.5  14.9  330  30 15   4.5   2.5
 12000 -10.0  14.0  355  32 17   0.3   0.2 |  -9.1  15.6  330  26 14   2.4   1.3
 11750  -9.7  14.5  355  33 17   4.9   2.7 |  -8.8  16.2  330  25 13   4.9   2.7
 11500  -9.4  15.1  355  33 17   3.7   2.0 |  -8.5  16.7  335  25 13   4.1   2.3
 11250  -9.1  15.6  360  34 18   3.8   2.1 |  -8.1  17.4  335  24 12   4.8   2.6
 11000  -8.8  16.2  360  35 18   4.0   2.2 |  -7.8  18.0  340  23 12   4.5   2.5
 10750  -8.5  16.7  360  35 18   4.8   2.7 |  -7.5  18.5  345  22 12   3.5   1.9
 10500  -8.1  17.4  360  35 18   5.0   2.7 |  -7.2  19.0  350  22 11   3.3   1.8
 10250  -7.8  18.0  005  36 18   5.0   2.7 |  -7.0  19.4  355  21 11   3.6   2.0
 10000  -7.4  18.7  005  37 19   5.2   2.9 |  -6.6  20.1  355  20 10   5.4   3.0
  9750  -7.0  19.4  005  37 19   5.7   3.1 |  -6.2  20.8  355  19 10   7.1   3.9
  9500  -6.6  20.1  005  37 19   5.9   3.2 |  -5.7  21.7  355  17  9   7.0   3.9
  9250  -6.2  20.8  005  37 19   6.1   3.3 |  -5.2  22.6  360  16  8   7.9   4.3
  9000  -5.7  21.7  360  36 19   5.8   3.2 |  -4.5  23.9  360  16  8   9.1   5.0
  8750  -5.3  22.5  360  34 18   7.7   4.2 |  -3.8  25.2  360  16  8  10.0   5.5
  8500  -4.6  23.7  355  32 17   9.7   5.3 |  -3.1  26.4  360  16  8  10.6   5.8
  8250  -3.9  25.0  355  30 16   9.6   5.3 |  -2.3  27.9  360  15  8  10.7   5.9
  8000  -3.2  26.2  350  29 15  10.3   5.6 |  -1.5  29.3  360  15  8  11.6   6.4
  7750  -2.5  27.5  350  27 14   9.4   5.2 |  -0.6  30.9  360  15  8   9.7   5.3
  7500  -1.8  28.8  350  25 13   8.4   4.6 |   0.0  32.0  360  14  7   9.7   5.3
  7250  -1.2  29.8  350  23 12   8.4   4.6 |   0.9  33.6  360  14  7  13.3   7.3
  7000  -0.6  30.9  350  21 11   8.4   4.6 |   1.9  35.4  360  13  7  13.7   7.5
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/19/2015 at 1500 MDT          |       04/19/2015 at 1800 MDT
                                           |
K index... +18.7  LI... +274.2             | K index... +20.2  LI... +273.8
CAPE... +12.7  CIN... -3.3                 | CAPE... 0.0  CIN... -0.9
                                           |
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 -56.0 -68.8  265  19 10   2.3   1.2 | -55.8 -68.4  270  19 10   2.1   1.2
 45000 -52.6 -62.7  275  23 12   2.2   1.2 | -52.6 -62.7  275  21 11   2.0   1.1
 40000 -49.7 -57.5  285  28 15   1.8   1.0 | -50.0 -58.0  285  27 14   1.7   0.9
 38000 -50.1 -58.2  290  28 15  -3.9  -2.1 | -50.1 -58.2  290  29 15  -3.4  -1.9
 36000 -52.5 -62.5  300  26 14  -3.9  -2.1 | -52.2 -62.0  295  29 15  -3.4  -1.9
 34000 -54.6 -66.3  310  25 13   2.5   1.4 | -54.1 -65.4  305  29 15   4.6   2.5
 32000 -51.0 -59.8  320  26 13   6.1   3.3 | -50.8 -59.4  305  32 16   5.4   2.9
 30000 -47.3 -53.1  325  28 14   7.3   4.0 | -47.4 -53.3  305  34 18   8.2   4.5
 29000 -45.1 -49.2  325  28 14   7.5   4.1 | -45.1 -49.2  300  35 18   7.9   4.3
 28000 -42.8 -45.0  320  28 14   7.5   4.1 | -42.7 -44.9  300  36 19   7.9   4.3
 27000 -40.0 -40.0  320  28 15   7.7   4.2 | -40.4 -40.7  300  37 19   7.9   4.3
 26000 -37.6 -35.7  320  29 15   8.0   4.4 | -37.9 -36.2  300  37 19   8.2   4.5
 25000 -35.2 -31.4  315  30 16   8.0   4.4 | -35.5 -31.9  300  36 19   8.2   4.5
 24000 -32.8 -27.0  315  31 16   8.0   4.4 | -33.0 -27.4  305  36 18   8.3   4.5
 23000 -30.5 -22.9  310  31 16   8.0   4.4 | -30.7 -23.3  305  36 18   7.7   4.2
 22000 -28.1 -18.6  310  30 16   8.0   4.4 | -28.3 -18.9  305  35 18   7.8   4.3
 21000 -25.7 -14.3  305  30 16   7.5   4.1 | -26.0 -14.8  310  35 18   7.6   4.2
 20000 -23.6 -10.5  310  32 17   7.1   3.9 | -23.8 -10.8  310  36 18   7.4   4.1
 19500 -22.6  -8.7  310  34 17   7.1   3.9 | -22.7  -8.9  305  36 19   7.4   4.1
 19000 -21.5  -6.7  315  35 18   7.1   3.9 | -21.6  -6.9  305  37 19   7.4   4.1
 18500 -20.5  -4.9  315  36 19   6.7   3.7 | -20.5  -4.9  305  37 19   7.4   4.0
 18000 -19.6  -3.3  315  38 20   5.7   3.1 | -19.5  -3.1  305  36 19   6.9   3.8
 17500 -18.8  -1.8  315  40 21   5.7   3.1 | -18.5  -1.3  305  35 18   6.9   3.8
 17000 -17.9  -0.2  315  41 21   6.7   3.7 | -17.5   0.5  305  34 18   6.8   3.7
 16500 -16.9   1.6  315  41 21   6.6   3.6 | -16.0   3.2  305  32 17   6.6   3.6
 16000 -15.9   3.4  315  40 21   6.7   3.7 | -14.9   5.2  305  31 16   8.4   4.6
 15500 -15.0   5.0  315  39 20   6.8   3.7 | -13.6   7.5  305  29 15   8.3   4.5
 15000 -14.0   6.8  315  38 20   7.2   4.0 | -12.5   9.5  300  28 14   7.6   4.2
 14500 -12.8   9.0  310  35 18   8.2   4.5 | -11.4  11.5  300  26 14   7.5   4.1
 14000 -11.6  11.1  310  31 16   8.1   4.4 | -10.3  13.5  300  25 13   6.8   3.7
 13500 -10.1  13.8  305  28 14   6.3   3.5 |  -9.3  15.3  300  23 12   6.3   3.5
 13000  -9.2  15.4  305  26 13   6.2   3.4 |  -8.4  16.9  300  22 11   5.7   3.1
 12500  -8.3  17.1  310  24 12   6.4   3.5 |  -7.7  18.1  305  20 10   4.9   2.7
 12000  -7.5  18.5  315  22 11   4.4   2.4 |  -7.0  19.4  315  19 10   4.1   2.2
 11750  -7.2  19.0  320  20 11   4.9   2.7 |  -6.7  19.9  320  17  9   4.1   2.2
 11500  -6.8  19.8  325  19 10   4.5   2.5 |  -6.4  20.5  325  16  8   4.2   2.3
 11250  -6.5  20.3  330  19 10   5.6   3.1 |  -6.1  21.0  335  16  8   3.7   2.0
 11000  -6.0  21.2  335  17  9   6.1   3.4 |  -5.8  21.6  340  15  8   4.6   2.5
 10750  -5.6  21.9  340  16  8   5.5   3.0 |  -5.4  22.3  350  15  8   6.5   3.6
 10500  -5.2  22.6  350  16  8   5.6   3.1 |  -4.9  23.2  355  15  8   6.8   3.7
 10250  -4.8  23.4  355  16  8   5.9   3.2 |  -4.4  24.1  360  15  8   6.6   3.6
 10000  -4.3  24.3  360  16  8   8.3   4.6 |  -3.9  25.0  005  15  8   8.4   4.6
  9750  -3.6  25.5  360  16  8   9.8   5.4 |  -3.2  26.2  005  15  8  10.0   5.5
  9500  -2.9  26.8  005  15  8   9.3   5.1 |  -2.5  27.5  005  15  8   9.6   5.3
  9250  -2.2  28.0  005  15  8   9.5   5.2 |  -1.8  28.8  005  15  8   9.7   5.3
  9000  -1.5  29.3  005  15  8   9.6   5.2 |  -1.1  30.0  005  15  8   9.4   5.2
  8750  -0.8  30.6  005  15  8  10.4   5.7 |  -0.4  31.3  005  15  8   9.8   5.4
  8500   0.0  32.0  005  15  8  11.2   6.1 |   0.4  32.7  005  15  8  10.2   5.6
  8250   0.8  33.4  005  15  8  10.7   5.9 |   1.2  34.2  005  15  8  10.3   5.6
  8000   1.6  34.9  005  15  8  10.8   5.9 |   2.0  35.6  005  15  7  11.0   6.0
  7750   2.4  36.3  005  15  8   9.7   5.3 |   2.8  37.0  005  14  7   9.6   5.3
  7500   3.1  37.6  005  14  7   9.5   5.2 |   3.4  38.1  005  14  7   7.8   4.3
  7250   3.9  39.0  010  14  7  12.9   7.1 |   4.0  39.2  005  13  7   8.7   4.8
  7000   4.9  40.8  010  13  7  15.2   8.3 |   4.6  40.3  005  12  6   9.5   5.2
  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.