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938
UXUS97 KPUB 301027
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0427 MDT Thursday, October 30, 2014

This forecast is for Thursday, October 30, 2014:

If the trigger temperature of 54.9 F/12.7 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 365 ft/min (1.9 m/s)
   Maximum height of thermals.................. 11256 ft MSL (4498 ft AGL)

Forecast maximum temperature................... 56.0 F/13.8 C
Time of trigger temperature.................... 1415 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................. 9014 ft MSL (2256 ft AGL)
Thermal soaring outlook for Friday 10/31....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 34856 ft MSL (28098 ft AGL)
Wave soaring outlook for Friday 10/31.......... Poor

Remarks...

Sunrise/Sunset.................... 07:24:16 / 18:01:56 MDT
Total possible sunshine........... 10 hr 37 min 40 sec (637 min 40 sec)
Altitude of sun at 12:42:46 MDT... 37.14 degrees

Upper air data from numerical model forecast valid on 10/30/2014 at 0600 MDT

Freezing level.................. 11770 ft MSL (5012 ft AGL)
Convective condensation level... 20493 ft MSL (13735 ft AGL)
Lifted condensation level....... 15671 ft MSL (8913 ft AGL)
Lifted index.................... +8.7
K index......................... +8.0

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  -64.8 -84.6   270   26   13   3.5   1.9      M     M       M      M    M
 45000  -58.6 -73.5   275   33   17   6.6   3.6      M     M       M      M    M
 40000  -48.7 -55.7   295   40   21   4.7   2.6      M     M       M      M    M
 38000  -47.9 -54.2   310   42   22   1.2   0.6      M     M       M      M    M
 36000  -47.2 -53.0   325   47   24   1.2   0.6      M     M       M      M    M
 34000  -45.0 -49.0   330   51   26   6.0   3.3      M     M       M      M    M
 32000  -40.9 -41.6   335   53   27   6.0   3.3      M     M       M      M    M
 30000  -36.8 -34.2   335   53   27   7.3   4.0   33.3  91.9    15.4      M    M
 29000  -34.6 -30.3   330   54   28   7.3   4.0   32.4  90.2    14.8      M    M
 28000  -32.4 -26.3   330   54   28   7.3   4.0   31.5  88.8    14.4      M    M
 27000  -30.0 -22.0   325   53   27   8.1   4.5   30.8  87.4    14.0      M    M
 26000  -27.6 -17.7   325   51   26   8.1   4.5   30.2  86.3    13.6      M    M
 25000  -25.1 -13.2   325   49   25   8.1   4.5   29.6  85.3    13.3      M    M
 24000  -22.9  -9.2   320   48   25   6.8   3.7   28.8  83.9    12.8      M    M
 23000  -20.9  -5.6   320   47   24   6.8   3.7   27.7  81.9    12.0      M    M
 22000  -18.8  -1.8   320   46   24   6.8   3.8   26.7  80.1    11.3      M    M
 21000  -16.6   2.1   320   45   23   8.0   4.4   26.0  78.7    10.7      M    M
 20000  -14.2   6.4   320   43   22   8.1   4.4   25.3  77.6    10.2      M    M
 19500  -13.0   8.6   315   43   22   8.1   4.4   25.1  77.1    10.0      M    M
 19000  -11.8  10.8   315   42   21   7.8   4.3   24.8  76.7     9.9      M    M
 18500  -10.8  12.6   320   41   21   7.1   3.9   24.4  75.9     9.5      M    M
 18000   -9.7  14.5   320   41   21   7.3   4.0   24.0  75.1     9.1      M    M
 17500   -8.8  16.2   320   40   21   4.3   2.4   23.3  74.0     8.6      M    M
 17000   -8.2  17.2   320   40   20   4.1   2.3   22.4  72.3     7.8      M    M
 16500   -7.7  18.1   320   39   20   3.9   2.1   21.5  70.6     7.0      M    M
 16000   -6.9  19.6   320   37   19   3.6   1.9   19.9  67.8     5.6      M    M
 15500   -6.3  20.7   320   35   18   4.2   2.3   18.9  66.1     4.7      M    M
 15000   -5.7  21.7   315   33   17   4.5   2.4   18.0  64.5     3.9      M    M
 14500   -5.0  23.0   315   31   16   4.9   2.7   17.2  63.0     3.2      M    M
 14000   -4.2  24.4   315   29   15   5.7   3.1   16.5  61.7     2.5      M    M
 13500   -3.3  26.1   315   26   13   5.9   3.2   15.9  60.5     1.9      M    M
 13000   -2.4  27.7   310   24   12   6.7   3.7   15.3  59.6     1.4      M    M
 12500   -1.4  29.5   310   21   11   6.4   3.5   14.8  58.7     1.0      M    M
 12000   -0.4  31.3   310   19   10   7.2   4.0   14.3  57.8     0.5      M    M
 11750    0.2  32.4   310   19   10   7.1   3.9   14.1  57.5     0.4      M    M
 11500    0.7  33.3   310   18    9   7.1   3.9   13.9  57.1     0.2      M    M
 11250    1.2  34.2   310   17    9   6.6   3.6   13.7  56.7    -0.1    359  1.8
 11000    1.7  35.1   315   17    9   5.7   3.1   13.4  56.2    -0.3    338  1.7
 10750    2.1  35.8   320   17    9   5.2   2.8   13.1  55.6    -0.7    318  1.6
 10500    2.5  36.5   320   17    9   5.3   2.9   12.7  54.9    -1.0    299  1.5
 10250    2.9  37.2   325   17    9   5.5   3.0   12.4  54.3    -1.3    280  1.4
 10000    3.3  37.9   335   17    9   5.4   3.0   12.1  53.7    -1.7    260  1.3
  9750    3.7  38.7   340   17    9   4.9   2.7   11.7  53.1    -2.0    241  1.2
  9500    4.0  39.2   340   17    9   5.1   2.8   11.4  52.4    -2.4    223  1.1
  9250    4.4  39.9   345   17    9   5.6   3.1   11.0  51.8    -2.7    204  1.0
  9000    4.9  40.8   350   17    9   5.6   3.1   10.7  51.3    -3.0    184  0.9
  8750    5.3  41.5   355   17    9   6.0   3.3   10.4  50.7    -3.4    164  0.8
  8500    5.7  42.3   360   18    9   5.6   3.1   10.1  50.2    -3.7    143  0.7
  8250    6.1  43.0   360   18    9   3.5   1.9    9.7  49.5    -4.0    124  0.6
  8000    6.5  43.7   360   17    9   8.1   4.5    9.3  48.8    -4.4    106  0.5
  7750    6.8  44.2   360   17    9  -8.3  -4.5    8.9  48.1    -4.8     88  0.4
  7500    5.3  41.5   360   16    8 -19.7 -10.8    6.9  44.4    -6.9    125  0.6
  7250    4.4  39.9   355   13    7  -9.4  -5.2    5.6  42.0    -8.2    146  0.7
  7000    3.4  38.1   345   10    5 -18.5 -10.2    4.2  39.6    -9.5    167  0.8
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           10/30/2014 at 0900 MDT          |       10/30/2014 at 1200 MDT
                                           |
K index... +8.4  LI... +5.6                | K index... +8.6  LI... +5.8
CAPE... 0.0  CIN... -0.0                   | 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  270  26 13   3.4   1.9 | -64.4 -83.9  265  32 16   3.5   1.9
 45000 -58.5 -73.3  280  33 17   5.6   3.0 | -58.9 -74.0  270  38 20   4.4   2.4
 40000 -50.2 -58.4  295  40 21   4.9   2.7 | -52.3 -62.1  295  38 20   4.1   2.2
 38000 -48.9 -56.0  315  42 22   1.7   0.9 | -50.4 -58.7  310  38 20   3.1   1.7
 36000 -47.9 -54.2  330  47 24   1.6   0.9 | -48.3 -54.9  330  42 21   3.1   1.7
 34000 -45.1 -49.2  330  49 25   6.5   3.6 | -45.0 -49.0  335  46 24   6.7   3.7
 32000 -41.2 -42.2  330  50 25   6.5   3.6 | -40.9 -41.6  335  49 25   6.7   3.7
 30000 -36.9 -34.4  330  48 25   7.7   4.2 | -36.6 -33.9  330  51 26   7.5   4.1
 29000 -34.5 -30.1  330  47 24   7.7   4.2 | -34.4 -29.9  330  51 26   7.5   4.1
 28000 -32.2 -26.0  330  47 24   7.7   4.2 | -32.1 -25.8  330  51 26   7.5   4.1
 27000 -30.0 -22.0  325  46 24   7.5   4.1 | -29.9 -21.8  325  51 26   7.6   4.2
 26000 -27.7 -17.9  325  47 24   7.5   4.1 | -27.6 -17.7  325  50 26   7.6   4.2
 25000 -25.5 -13.9  325  47 24   7.5   4.1 | -25.3 -13.5  325  49 25   7.6   4.2
 24000 -22.8  -9.0  325  47 24   6.9   3.8 | -23.1  -9.6  325  49 25   7.5   4.1
 23000 -20.8  -5.4  325  47 24   6.9   3.8 | -20.3  -4.5  325  49 25   7.5   4.1
 22000 -18.8  -1.8  320  47 24   6.8   3.7 | -18.1  -0.6  325  50 26   7.6   4.2
 21000 -16.6   2.1  320  46 24   7.4   4.1 | -16.0   3.2  325  48 25   6.6   3.6
 20000 -14.4   6.1  320  44 23   7.4   4.1 | -14.1   6.6  325  45 23   6.6   3.6
 19500 -13.3   8.1  320  43 22   7.4   4.1 | -13.1   8.4  325  44 23   6.6   3.6
 19000 -12.2  10.0  320  42 22   7.8   4.3 | -12.1  10.2  325  43 22   6.8   3.8
 18500 -11.1  12.0  320  41 21   7.9   4.3 | -11.1  12.0  325  41 21   6.9   3.8
 18000  -9.9  14.2  320  41 21   7.7   4.2 | -10.1  13.8  325  40 21   6.7   3.7
 17500  -9.0  15.8  320  40 21   4.8   2.7 |  -9.3  15.3  325  38 20   5.4   2.9
 17000  -8.3  17.1  325  39 20   5.1   2.8 |  -8.5  16.7  325  37 19   5.6   3.1
 16500  -7.6  18.3  325  38 20   3.5   1.9 |  -7.8  18.0  325  35 18   4.1   2.2
 16000  -7.2  19.0  325  36 19   3.3   1.8 |  -7.2  19.0  325  33 17   4.0   2.2
 15500  -6.7  19.9  325  34 18   3.5   1.9 |  -6.6  20.1  325  31 16   4.1   2.3
 15000  -6.1  21.0  320  32 17   3.9   2.1 |  -5.9  21.4  325  29 15   4.3   2.4
 14500  -5.6  21.9  320  30 15   4.1   2.3 |  -5.3  22.5  325  27 14   4.5   2.5
 14000  -4.8  23.4  320  28 15   5.4   3.0 |  -4.6  23.7  325  26 13   5.1   2.8
 13500  -4.0  24.8  320  27 14   5.4   2.9 |  -3.8  25.2  320  24 12   5.1   2.8
 13000  -3.1  26.4  315  25 13   6.5   3.5 |  -3.0  26.6  320  22 11   6.6   3.6
 12500  -2.2  28.0  315  22 11   6.5   3.6 |  -2.0  28.4  315  20 10   6.5   3.6
 12000  -1.3  29.7  315  21 11   6.3   3.5 |  -1.1  30.0  310  18  9   6.6   3.6
 11750  -0.8  30.6  315  20 10   7.5   4.1 |  -0.6  30.9  310  17  9   7.7   4.2
 11500  -0.2  31.6  315  19 10   7.4   4.1 |  -0.0  32.0  310  16  8   7.5   4.1
 11250   0.3  32.5  315  18  9   6.6   3.6 |   0.5  32.9  305  15  8   6.8   3.7
 11000   0.7  33.3  320  18  9   5.6   3.1 |   1.0  33.8  305  14  7   6.2   3.4
 10750   1.2  34.2  320  17  9   5.4   3.0 |   1.5  34.7  300  13  7   6.7   3.7
 10500   1.6  34.9  320  17  9   5.3   2.9 |   2.0  35.6  300  13  7   6.7   3.7
 10250   1.9  35.4  325  17  9   4.9   2.7 |   2.5  36.5  300  12  6   5.8   3.2
 10000   2.3  36.1  330  16  8   4.8   2.7 |   2.8  37.0  300  11  6   5.0   2.8
  9750   2.9  37.2  335  16  8   3.1   1.7 |   3.2  37.8  300  10  5   5.2   2.9
  9500   3.1  37.6  340  15  8   4.2   2.3 |   4.1  39.4  305   7  4   7.4   4.0
  9250   3.5  38.3  345  15  8   4.9   2.7 |   4.6  40.3  310   6  3   8.3   4.5
  9000   3.8  38.8  350  14  7   4.3   2.3 |   5.2  41.4  320   4  2   7.8   4.3
  8750   4.1  39.4  355  14  7   3.8   2.1 |   5.8  42.4  335   3  2   8.9   4.9
  8500   4.4  39.9  355  14  7   4.7   2.6 |   6.5  43.7  345   3  1  10.5   5.7
  8250   4.8  40.6  355  14  7   4.4   2.4 |   7.3  45.1  350   3  1  10.7   5.9
  8000   5.1  41.2  360  14  7   6.7   3.7 |   8.1  46.6  350   3  1  10.3   5.7
  7750   5.7  42.3  360  14  7   6.1   3.3 |   9.0  48.2  360   3  1  14.3   7.9
  7500   5.9  42.6  350  10  5  -1.9  -1.0 |  10.3  50.5  005   2  1  21.8  11.9
  7250   6.1  43.0  335   6  3  14.4   7.9 |  11.7  53.1  010   2  1   8.3   4.6
  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

           10/30/2014 at 1500 MDT          |       10/30/2014 at 1800 MDT
                                           |
K index... +4.8  LI... +6.2                | K index... -0.5  LI... +4.2
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  265  33 17   3.3   1.8 | -64.6 -84.3  275  34 17   3.8   2.1
 45000 -59.4 -74.9  275  39 20   2.6   1.4 | -59.3 -74.7  285  39 20   1.5   0.8
 40000 -55.5 -67.9  300  34 18   3.4   1.9 | -57.1 -70.8  305  35 18   3.9   2.1
 38000 -52.5 -62.5  310  34 17   5.2   2.8 | -53.5 -64.3  305  35 18   5.9   3.3
 36000 -49.0 -56.2  315  34 18   5.2   2.8 | -50.0 -58.0  305  35 18   5.9   3.2
 34000 -45.0 -49.0  325  38 20   7.3   4.0 | -45.8 -50.4  315  36 19   7.5   4.1
 32000 -40.6 -41.1  335  44 22   7.3   4.0 | -41.3 -42.3  320  40 20   7.5   4.1
 30000 -36.1 -33.0  335  47 24   7.8   4.3 | -36.5 -33.7  325  42 22   8.4   4.6
 29000 -33.7 -28.7  330  48 25   7.8   4.3 | -34.0 -29.2  320  43 22   8.4   4.6
 28000 -31.4 -24.5  330  49 25   7.9   4.3 | -31.5 -24.7  320  44 23   8.4   4.6
 27000 -29.1 -20.4  330  49 25   7.5   4.1 | -28.5 -19.3  320  45 23   7.8   4.3
 26000 -26.9 -16.4  325  49 25   7.5   4.1 | -26.2 -15.2  325  45 23   7.9   4.3
 25000 -24.6 -12.3  325  50 26   7.5   4.1 | -23.8 -10.8  325  46 24   7.9   4.3
 24000 -22.4  -8.3  320  50 26   7.4   4.1 | -21.5  -6.7  325  47 24   7.5   4.1
 23000 -19.6  -3.3  320  51 26   7.4   4.1 | -19.3  -2.7  325  48 25   7.5   4.1
 22000 -17.4   0.7  320  52 27   7.4   4.1 | -17.0   1.4  325  49 25   7.7   4.2
 21000 -15.3   4.5  320  51 26   6.9   3.8 | -15.1   4.8  325  49 25   6.1   3.3
 20000 -13.2   8.2  320  50 26   6.9   3.8 | -13.3   8.1  320  50 26   6.1   3.3
 19500 -12.2  10.0  320  49 25   7.0   3.8 | -12.3   9.9  320  50 26   6.1   3.3
 19000 -11.2  11.8  320  48 25   5.4   3.0 | -11.4  11.5  320  50 26   6.4   3.5
 18500 -10.4  13.3  320  46 24   5.2   2.9 | -10.4  13.3  320  48 25   6.5   3.5
 18000  -9.7  14.5  320  44 23   5.4   2.9 |  -9.5  14.9  320  46 24   6.4   3.5
 17500  -8.9  16.0  320  42 21   5.8   3.2 |  -8.6  16.5  320  44 22   5.0   2.8
 17000  -8.1  17.4  320  39 20   6.0   3.3 |  -7.9  17.8  320  41 21   5.2   2.9
 16500  -7.4  18.7  320  37 19   4.4   2.4 |  -7.2  19.0  320  38 19   4.5   2.4
 16000  -6.8  19.8  320  35 18   4.3   2.3 |  -6.6  20.1  320  35 18   4.5   2.5
 15500  -6.2  20.8  325  33 17   4.5   2.5 |  -6.0  21.2  320  32 16   5.0   2.7
 15000  -5.5  22.1  325  31 16   4.6   2.5 |  -5.3  22.5  315  29 15   5.4   3.0
 14500  -4.8  23.4  325  29 15   4.8   2.6 |  -4.5  23.9  315  26 13   5.7   3.1
 14000  -4.0  24.8  325  27 14   5.4   3.0 |  -3.6  25.5  310  23 12   6.9   3.8
 13500  -3.3  26.1  325  26 13   5.4   3.0 |  -2.6  27.3  300  21 11   6.9   3.8
 13000  -2.4  27.7  325  24 12   6.2   3.4 |  -1.5  29.3  295  18  9   7.6   4.2
 12500  -1.5  29.3  325  21 11   6.2   3.4 |  -0.4  31.3  295  15  8   8.3   4.6
 12000  -0.7  30.7  325  17  9   5.5   3.0 |   0.2  32.4  290   9  5   2.2   1.2
 11750  -0.3  31.5  325  14  7   6.0   3.3 |   0.6  33.1  290   7  4   4.9   2.7
 11500   0.2  32.4  325  12  6   6.0   3.3 |   0.9  33.6  290   5  2   4.0   2.2
 11250   0.6  33.1  325   9  5   5.4   2.9 |   1.2  34.2  285   2  1   4.9   2.7
 11000   1.0  33.8  330   6  3   5.7   3.1 |   1.6  34.9  240   1  1   5.3   2.9
 10750   1.5  34.7  335   4  2   7.4   4.1 |   2.0  35.6  180   2  1   4.9   2.7
 10500   2.0  35.6  360   2  1   7.6   4.2 |   2.3  36.1  155   3  1   4.5   2.5
 10250   2.6  36.7  065   1  1   8.3   4.6 |   3.2  37.8  145   5  2   7.7   4.2
 10000   3.2  37.8  085   1  1   9.1   5.0 |   3.8  38.8  145   5  3   6.1   3.3
  9750   3.9  39.0  105   2  1   8.6   4.7 |   4.2  39.6  145   6  3   5.0   2.8
  9500   5.2  41.4  115   2  1   9.9   5.4 |   4.6  40.3  145   6  3   6.7   3.7
  9250   6.0  42.8  120   2  1  10.7   5.9 |   5.2  41.4  145   7  3   7.9   4.3
  9000   6.8  44.2  120   2  1   9.9   5.4 |   5.7  42.3  150   7  3   7.0   3.8
  8750   7.5  45.5  125   3  1   9.4   5.2 |   6.2  43.2  150   7  4   6.7   3.7
  8500   8.2  46.8  125   3  2  10.0   5.5 |   6.8  44.2  150   7  4   8.2   4.5
  8250   9.0  48.2  125   3  2  10.4   5.7 |   7.4  45.3  150   7  4   8.7   4.8
  8000   9.7  49.5  125   3  2   9.9   5.4 |   8.1  46.6  155   7  4   8.9   4.9
  7750  10.6  51.1  125   3  2  13.9   7.6 |   8.6  47.5  155   8  4   4.9   2.7
  7500  11.9  53.4  125   4  2  21.6  11.9 |   8.7  47.7  155   6  3  -2.8  -1.5
  7250  13.2  55.8  120   4  2   7.6   4.1 |   8.7  47.7  155   4  2  11.2   6.1
  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




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NOAA National Weather Service
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Silver Spring, MD 20910
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Page last modified: May 16, 2007
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