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 13

000
UXUS97 KPUB 291133
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0432 MST Thursday, January 29, 2015

This forecast is for Thursday, January 29, 2015:

If the trigger temperature of 43.3 F/6.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 10626 ft MSL (3455 ft AGL)

Forecast maximum temperature................... 40.0 F/4.9 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
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................. 9748 ft MSL (2577 ft AGL)
Thermal soaring outlook for Friday 01/30....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:07:49 / 17:15:28 MST
Total possible sunshine........... 10 hr 7 min 39 sec (607 min 39 sec)
Altitude of sun at 12:12:01 MST... 33.24 degrees

Upper air data from numerical model forecast valid on 01/29/2015 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 13497 ft MSL (6326 ft AGL)
Lifted condensation level....... 11715 ft MSL (4545 ft AGL)
Lifted index.................... +10.3
K index......................... +6.6

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  -61.5 -78.7   280   38   20   3.5   1.9      M     M       M      M    M
 45000  -56.5 -69.7   280   53   27  -0.4  -0.2      M     M       M      M    M
 40000  -58.2 -72.8   285   82   42  -1.1  -0.6      M     M       M      M    M
 38000  -56.9 -70.4   280   91   47   4.0   2.2      M     M       M      M    M
 36000  -54.4 -65.9   280   99   51   4.0   2.2      M     M       M      M    M
 34000  -51.3 -60.3   275  101   52   8.0   4.4      M     M       M      M    M
 32000  -46.4 -51.5   275   91   47   8.1   4.4      M     M       M      M    M
 30000  -41.6 -42.9   275   81   42   8.1   4.4   29.8  85.6    19.4      M    M
 29000  -39.2 -38.6   280   76   39   8.1   4.4   29.1  84.3    19.0      M    M
 28000  -36.7 -34.1   285   71   37   8.1   4.4   28.5  83.2    18.8      M    M
 27000  -34.0 -29.2   290   65   33   4.9   2.7   27.4  81.4    18.2      M    M
 26000  -32.4 -26.3   290   57   29   5.1   2.8   25.6  78.1    17.0      M    M
 25000  -30.9 -23.6   290   48   25   5.1   2.8   23.9  75.0    15.8      M    M
 24000  -29.2 -20.6   290   41   21   7.3   4.0   22.5  72.4    14.8      M    M
 23000  -27.0 -16.6   290   37   19   7.5   4.1   21.6  70.8    14.3      M    M
 22000  -24.7 -12.5   290   34   17   7.5   4.1   20.8  69.4    13.8      M    M
 21000  -22.6  -8.7   295   31   16   6.7   3.7   20.0  67.9    13.2      M    M
 20000  -20.5  -4.9   295   28   15   6.7   3.7   18.9  65.9    12.4      M    M
 19500  -19.5  -3.1   290   27   14   6.7   3.7   18.3  65.0    12.0      M    M
 19000  -18.5  -1.3   290   26   13   6.8   3.7   17.9  64.2    11.7      M    M
 18500  -17.5   0.5   290   25   13   6.5   3.6   17.4  63.2    11.3      M    M
 18000  -16.6   2.1   290   24   12   6.5   3.6   16.8  62.2    10.8      M    M
 17500  -15.6   3.9   290   23   12   4.8   2.6   16.2  61.2    10.4      M    M
 17000  -15.1   4.8   285   22   12   3.6   2.0   15.2  59.3     9.5      M    M
 16500  -14.6   5.7   285   22   11   3.6   2.0   14.2  57.5     8.6      M    M
 16000  -14.1   6.6   280   21   11   4.0   2.2   13.2  55.7     7.7      M    M
 15500  -13.5   7.7   280   22   11   3.9   2.1   12.2  54.0     6.8      M    M
 15000  -12.9   8.8   275   22   11   5.5   3.0   11.4  52.5     6.0      M    M
 14500  -12.1  10.2   270   22   11   5.3   2.9   10.7  51.2     5.4      M    M
 14000  -11.2  11.8   270   21   11   7.1   3.9   10.1  50.1     4.8      M    M
 13500  -10.1  13.8   270   19   10   7.3   4.0    9.7  49.4     4.5      M    M
 13000   -9.1  15.6   270   17    9   6.9   3.8    9.3  48.7     4.1      M    M
 12500   -8.1  17.4   265   16    8   6.9   3.8    8.8  47.8     3.6      M    M
 12000   -7.2  19.0   260   15    8   4.9   2.7    8.2  46.8     3.1      M    M
 11750   -6.8  19.8   265   15    8   5.1   2.8    7.8  46.1     2.7      M    M
 11500   -6.4  20.5   265   14    7   6.0   3.3    7.5  45.5     2.4      M    M
 11250   -6.0  21.2   270   14    7   4.8   2.6    7.2  44.9     2.1      M    M
 11000   -5.7  21.7   275   14    7   2.8   1.5    6.7  44.0     1.6      M    M
 10750   -5.7  21.7   290   13    7  -1.5  -0.8    6.0  42.8     1.0      M    M
 10500   -5.9  21.4   300   13    7  -5.0  -2.7    4.9  40.9    -0.0    323  1.6
 10250   -6.4  20.5   320   13    7  -0.6  -0.3    3.0  37.4    -1.9    321  1.6
 10000   -6.4  20.5   335   13    7   0.7   0.4    2.2  36.0    -2.7    314  1.6
  9750   -6.3  20.7   350   14    7   2.1   1.2    1.6  34.8    -3.3    303  1.5
  9500   -6.0  21.2   360   15    8   4.5   2.5    1.1  33.9    -3.8    289  1.5
  9250   -5.6  21.9   005   16    8   5.9   3.2    0.7  33.3    -4.1    268  1.4
  9000   -5.2  22.6   005   16    8   5.3   2.9    0.4  32.8    -4.4    248  1.3
  8750   -4.8  23.4   005   17    9   5.6   3.0    0.1  32.2    -4.7    228  1.2
  8500   -4.3  24.3   005   18    9   7.6   4.2   -0.2  31.7    -5.0    207  1.1
  8250   -3.7  25.3   005   17    9   8.6   4.7   -0.3  31.5    -5.2    182  0.9
  8000   -3.1  26.4   360   17    9   8.9   4.9   -0.4  31.4    -5.3    156  0.8
  7750   -2.4  27.7   360   16    8   9.4   5.1   -0.4  31.3    -5.4    128  0.7
  7500   -1.8  28.8   360   13    7   8.0   4.4   -0.5  31.2    -5.5    102  0.5
  7250   -1.2  29.8   360   10    5  11.1   6.1   -0.5  31.0    -5.6     76  0.4
  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 * * * * * *

           01/29/2015 at 0800 MST          |       01/29/2015 at 1100 MST
                                           |
K index... +8.5  LI... +3.5                | K index... +2.0  LI... +5.1
CAPE... 0.0  CIN... -1.1                   | 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 -61.4 -78.5  290  41 21   3.1   1.7 | -61.7 -79.1  285  38 19   2.6   1.4
 45000 -56.8 -70.2  285  56 29  -0.1  -0.1 | -58.1 -72.6  285  52 27  -0.7  -0.4
 40000 -57.9 -72.2  280  79 41  -0.6  -0.3 | -58.9 -74.0  275  77 40  -0.5  -0.3
 38000 -56.3 -69.3  280  92 47   4.4   2.4 | -57.0 -70.6  275  86 44   4.8   2.6
 36000 -53.6 -64.5  280 107 55   4.4   2.4 | -54.2 -65.6  275  94 49   4.8   2.6
 34000 -50.5 -58.9  280 112 58   7.1   3.9 | -50.6 -59.1  275  98 51   8.2   4.5
 32000 -46.2 -51.2  280  97 50   7.1   3.9 | -45.7 -50.3  275  94 48   8.2   4.5
 30000 -41.8 -43.2  280  82 42   8.0   4.4 | -41.0 -41.8  280  85 44   6.9   3.8
 29000 -39.4 -38.9  280  75 39   8.0   4.4 | -39.0 -38.2  280  76 39   6.9   3.8
 28000 -37.0 -34.6  285  69 36   8.0   4.4 | -36.9 -34.4  280  67 35   6.9   3.8
 27000 -34.2 -29.6  285  61 32   5.3   2.9 | -34.4 -29.9  285  57 30   6.4   3.5
 26000 -32.6 -26.7  285  54 28   5.5   3.0 | -32.5 -26.5  285  52 27   6.4   3.5
 25000 -30.9 -23.6  285  48 25   5.5   3.0 | -30.5 -22.9  290  46 24   6.4   3.5
 24000 -29.1 -20.4  290  41 21   7.1   3.9 | -28.6 -19.5  290  41 21   7.1   3.9
 23000 -27.0 -16.6  290  38 20   7.1   3.9 | -26.5 -15.7  290  38 19   7.0   3.9
 22000 -24.9 -12.8  290  34 18   7.2   3.9 | -24.4 -11.9  295  34 18   7.0   3.9
 21000 -22.8  -9.0  290  31 16   6.3   3.5 | -22.3  -8.1  295  31 16   6.8   3.7
 20000 -20.9  -5.6  295  28 14   6.4   3.5 | -20.3  -4.5  300  28 15   6.8   3.7
 19500 -20.0  -4.0  295  26 13   6.4   3.5 | -19.3  -2.7  305  27 14   6.8   3.7
 19000 -19.0  -2.2  300  24 13   6.5   3.6 | -18.2  -0.8  305  26 13   6.8   3.7
 18500 -18.2  -0.8  300  23 12   4.9   2.7 | -17.3   0.9  310  24 12   6.5   3.5
 18000 -17.4   0.7  300  21 11   5.1   2.8 | -16.3   2.7  310  22 11   6.6   3.6
 17500 -16.7   1.9  305  19 10   4.2   2.3 | -15.4   4.3  315  20 11   4.3   2.4
 17000 -16.2   2.8  305  18  9   3.8   2.1 | -14.9   5.2  320  18  9   3.6   2.0
 16500 -15.7   3.7  305  16  8   4.5   2.5 | -14.4   6.1  320  15  8   3.2   1.7
 16000 -14.8   5.4  300  16  8   6.9   3.8 | -14.0   6.8  325  13  7   2.1   1.2
 15500 -13.8   7.2  295  16  8   6.8   3.7 | -13.8   7.2  330  11  6   2.2   1.2
 15000 -12.7   9.1  290  17  9   7.9   4.3 | -13.1   8.4  335  10  5   6.8   3.7
 14500 -11.6  11.1  285  18  9   8.0   4.4 | -12.2  10.0  340   9  5   6.4   3.5
 14000 -10.6  12.9  285  18  9   5.9   3.2 | -11.2  11.8  340   9  5   6.7   3.7
 13500  -9.7  14.5  290  17  9   5.9   3.2 | -10.2  13.6  340   9  4   6.8   3.8
 13000  -8.9  16.0  295  15  8   5.0   2.7 |  -9.3  15.3  340   8  4   5.3   2.9
 12500  -8.2  17.2  290  13  7   5.0   2.7 |  -8.6  16.5  340   7  3   5.6   3.1
 12000  -7.6  18.3  285  12  6   3.6   2.0 |  -8.0  17.6  335   5  3   2.5   1.4
 11750  -7.2  19.0  285  12  6   5.3   2.9 |  -7.8  18.0  315   4  2   4.0   2.2
 11500  -6.8  19.8  280  12  6   6.7   3.7 |  -7.4  18.7  300   5  2   5.1   2.8
 11250  -6.3  20.7  280  12  6   4.8   2.6 |  -7.1  19.2  285   5  3   3.6   2.0
 11000  -6.1  21.0  285  11  6   2.2   1.2 |  -6.9  19.6  280   5  3   2.2   1.2
 10750  -6.0  21.2  290  11  6  -0.8  -0.4 |  -6.8  19.8  280   6  3   1.1   0.6
 10500  -6.2  20.8  295  12  6  -3.6  -2.0 |  -6.8  19.8  275   6  3  -0.6  -0.3
 10250  -6.5  20.3  310  12  6   0.7   0.4 |  -6.6  20.1  280   5  3   2.9   1.6
 10000  -6.4  20.5  315  11  6   1.0   0.6 |  -6.4  20.5  295   4  2   2.9   1.6
  9750  -6.3  20.7  330  11  6   2.0   1.1 |  -6.1  21.0  315   4  2   4.3   2.4
  9500  -6.1  21.0  340  11  6   2.5   1.4 |  -5.7  21.7  330   4  2   5.6   3.1
  9250  -5.9  21.4  350  11  6   2.5   1.4 |  -5.3  22.5  340   3  2   6.0   3.3
  9000  -5.7  21.7  355  12  6   2.1   1.2 |  -4.9  23.2  350   3  2   5.6   3.1
  8750  -5.5  22.1  005  13  7   3.7   2.0 |  -4.4  24.1  010   3  1   7.1   3.9
  8500  -5.1  22.8  005  13  7   7.0   3.8 |  -3.8  25.2  025   3  1   8.8   4.9
  8250  -4.5  23.9  005  13  7   7.9   4.3 |  -3.2  26.2  030   3  1   9.0   4.9
  8000  -4.0  24.8  360  13  7   7.3   4.0 |  -2.5  27.5  035   2  1   8.3   4.5
  7750  -3.4  25.9  360  13  7   9.2   5.0 |  -1.8  28.8  040   2  1  12.1   6.7
  7500  -2.6  27.3  360  11  6  13.0   7.1 |  -0.6  30.9  045   2  1  20.7  11.4
  7250  -1.8  28.8  355   9  5   6.0   3.3 |   0.6  33.1  050   2  1   4.9   2.7
  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

           01/29/2015 at 1400 MST          |       01/29/2015 at 1700 MST
                                           |
K index... -12.7  LI... +5.3               | K index... -19.4  LI... +5.1
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... -0.5
                                           |
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 -61.9 -79.4  285  40 20   2.6   1.4 | -61.9 -79.4  285  40 20   2.9   1.6
 45000 -58.1 -72.6  280  54 28  -0.2  -0.1 | -57.7 -71.9  275  52 27  -1.0  -0.6
 40000 -58.2 -72.8  275  85 44  -0.0  -0.0 | -59.1 -74.4  265  87 45  -0.8  -0.5
 38000 -56.5 -69.7  270  90 46   4.1   2.3 | -57.3 -71.1  265  91 47   4.8   2.6
 36000 -54.1 -65.4  265  92 47   4.1   2.3 | -54.4 -65.9  265  90 46   4.8   2.6
 34000 -50.8 -59.4  265  91 47   8.2   4.5 | -50.9 -59.6  265  86 44   7.9   4.4
 32000 -45.8 -50.4  270  84 43   8.3   4.5 | -46.2 -51.2  270  75 39   8.0   4.4
 30000 -41.1 -42.0  275  75 39   7.0   3.8 | -41.4 -42.5  275  65 33   7.9   4.3
 29000 -39.0 -38.2  280  68 35   6.9   3.8 | -39.0 -38.2  275  58 30   7.9   4.3
 28000 -36.4 -33.5  285  59 30   6.9   3.8 | -36.1 -33.0  280  50 26   7.9   4.3
 27000 -34.3 -29.7  285  52 27   6.8   3.7 | -33.9 -29.0  280  44 22   6.5   3.6
 26000 -32.3 -26.1  290  46 24   6.8   3.7 | -31.9 -25.4  280  39 20   6.6   3.6
 25000 -30.3 -22.5  290  41 21   6.8   3.7 | -29.9 -21.8  285  34 17   6.6   3.6
 24000 -28.3 -18.9  295  36 18   6.4   3.5 | -28.0 -18.4  290  29 15   6.3   3.4
 23000 -26.3 -15.3  295  32 16   6.4   3.5 | -26.1 -15.0  290  25 13   6.3   3.5
 22000 -24.4 -11.9  295  28 14   6.4   3.5 | -24.2 -11.6  295  22 11   6.3   3.5
 21000 -22.4  -8.3  300  24 12   6.8   3.7 | -22.2  -8.0  300  18  9   6.5   3.6
 20000 -20.4  -4.7  305  20 11   6.7   3.7 | -20.3  -4.5  300  14  7   6.5   3.6
 19500 -19.4  -2.9  310  19 10   6.7   3.7 | -19.3  -2.7  300  12  6   6.5   3.6
 19000 -18.4  -1.1  310  17  9   6.7   3.7 | -18.3  -0.9  300   9  5   6.5   3.6
 18500 -17.4   0.7  315  15  8   6.2   3.4 | -17.4   0.7  300   7  4   6.2   3.4
 18000 -16.4   2.5  325  13  7   6.2   3.4 | -16.4   2.5  290   5  3   6.3   3.4
 17500 -15.5   4.1  335  11  6   5.3   2.9 | -15.5   4.1  275   3  2   5.3   2.9
 17000 -14.8   5.4  345  10  5   4.9   2.7 | -14.7   5.5  210   1  1   5.1   2.8
 16500 -14.1   6.6  355   9  5   5.0   2.8 | -14.0   6.8  135   3  1   5.5   3.0
 16000 -13.3   8.1  355   8  4   5.4   3.0 | -13.0   8.6  135   3  2   6.5   3.6
 15500 -12.5   9.5  355   7  4   5.6   3.1 | -12.1  10.2  135   4  2   6.6   3.6
 15000 -11.9  10.6  355   6  3   3.5   1.9 | -11.2  11.8  145   4  2   5.0   2.8
 14500 -11.4  11.5  355   4  2   3.7   2.0 | -10.5  13.1  160   4  2   5.5   3.0
 14000 -10.8  12.6  355   3  2   5.5   3.0 |  -9.8  14.4  165   4  2   4.5   2.4
 13500 -10.0  14.0  005   2  1   5.4   3.0 |  -9.2  15.4  175   5  3   4.6   2.5
 13000  -9.2  15.4  030   1  1   6.0   3.3 |  -8.5  16.7  175   5  3   5.3   2.9
 12500  -8.3  17.1  060   1  1   6.4   3.5 |  -7.8  18.0  175   5  3   5.6   3.1
 12000  -7.7  18.1  090   1  1   3.3   1.8 |  -7.1  19.2  175   6  3   4.7   2.6
 11750  -7.3  18.9  185   1  0   5.5   3.0 |  -6.7  19.9  185   6  3   6.5   3.6
 11500  -6.9  19.6  215   2  1   6.9   3.8 |  -6.2  20.8  190   6  3   7.3   4.0
 11250  -6.4  20.5  220   3  1   4.6   2.5 |  -5.7  21.7  195   6  3   5.7   3.1
 11000  -6.2  20.8  220   4  2   1.1   0.6 |  -5.4  22.3  200   7  4   2.5   1.4
 10750  -6.2  20.8  220   5  2   1.2   0.6 |  -5.2  22.6  200   8  4   3.0   1.7
 10500  -6.1  21.0  220   6  3   1.5   0.8 |  -4.9  23.2  200   8  4   4.4   2.4
 10250  -5.8  21.6  215   6  3   3.0   1.6 |  -4.4  24.1  195   8  4   3.4   1.9
 10000  -5.6  21.9  205   6  3   2.9   1.6 |  -4.1  24.6  195   9  5   3.3   1.8
  9750  -5.3  22.5  195   6  3   3.3   1.8 |  -3.9  25.0  190  10  5   3.1   1.7
  9500  -5.0  23.0  190   7  4   5.3   2.9 |  -3.7  25.3  195  11  6   2.7   1.5
  9250  -4.6  23.7  185   8  4   6.6   3.6 |  -3.5  25.7  190  11  6   2.5   1.3
  9000  -4.1  24.6  180   8  4   6.1   3.3 |  -3.3  26.1  190  12  6   2.3   1.2
  8750  -3.6  25.5  175   9  4   8.1   4.4 |  -3.2  26.2  190  12  6   4.0   2.2
  8500  -2.9  26.8  170   9  5  10.1   5.5 |  -2.8  27.0  185  13  7   6.6   3.6
  8250  -2.2  28.0  170   9  5  10.2   5.6 |  -2.3  27.9  185  13  7   7.0   3.9
  8000  -1.4  29.5  170   9  5   9.5   5.2 |  -1.7  28.9  180  13  7   6.9   3.8
  7750  -0.7  30.7  170   9  5  12.6   6.9 |  -1.2  29.8  185  12  6   6.9   3.8
  7500   0.5  32.9  170   9  4  20.2  11.1 |  -0.8  30.6  180  10  5   6.8   3.7
  7250   1.8  35.2  165   8  4   6.1   3.3 |  -0.3  31.5  175   7  4   7.2   3.9
  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
________________________________________________________________________________

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.