Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 111049
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0439 MDT Thursday, April 10, 2014

This forecast is for Thursday, April 10, 2014:

If the trigger temperature of 55.7 F/13.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1152 ft/min (5.9 m/s)
   Maximum height of thermals.................. 18785 ft MSL (12027 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13292 ft MSL (6534 ft AGL)
Thermal soaring outlook for Friday 04/11....... 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 NVA
Potential height of wave....................... 44995 ft MSL (38237 ft AGL)
Wave soaring outlook for Friday 04/11.......... Poor

Remarks...

Sunrise/Sunset.................... 06:29:49 / 19:30:26 MDT
Total possible sunshine........... 13 hr 0 min 37 sec (780 min 37 sec)
Altitude of sun at 13:00:16 MDT... 59.18 degrees

Upper air data from numerical model forecast valid on 04/10/2014 at 0600 MDT

Freezing level.................. 11799 ft MSL (5041 ft AGL)
Convective condensation level... 17158 ft MSL (10400 ft AGL)
Lifted condensation level....... 17229 ft MSL (10471 ft AGL)
Lifted index.................... +0.1
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  -59.8 -75.6   280   55   28   1.5   0.8      M     M       M      M    M
 45000  -57.6 -71.7   280   63   32  -0.8  -0.4      M     M       M      M    M
 40000  -60.7 -77.3   285   67   34  -2.1  -1.1      M     M       M      M    M
 38000  -59.5 -75.1   285   67   35   5.4   3.0      M     M       M      M    M
 36000  -56.2 -69.2   280   67   34   5.5   3.0      M     M       M      M    M
 34000  -52.1 -61.8   275   65   33   7.5   4.1      M     M       M      M    M
 32000  -47.6 -53.7   280   60   31   7.5   4.1      M     M       M      M    M
 30000  -42.9 -45.2   280   54   28   8.3   4.6   26.7  80.0     6.8      M    M
 29000  -40.4 -40.7   275   51   26   8.3   4.6   26.0  78.9     6.4      M    M
 28000  -37.9 -36.2   275   47   24   8.3   4.6   25.6  78.0     6.1      M    M
 27000  -35.4 -31.7   275   45   23   7.7   4.2   25.1  77.1     5.8      M    M
 26000  -33.1 -27.6   275   44   23   7.7   4.2   24.2  75.6     5.1      M    M
 25000  -30.8 -23.4   275   43   22   7.7   4.3   23.5  74.3     4.6      M    M
 24000  -28.5 -19.3   280   43   22   7.3   4.0   22.8  73.1     4.1      M    M
 23000  -26.3 -15.3   280   43   22   7.1   3.9   21.8  71.2     3.3      M    M
 22000  -24.2 -11.6   285   43   22   7.1   3.9   20.8  69.5     2.5      M    M
 21000  -22.1  -7.8   285   43   22   7.1   3.9   20.0  67.9     1.8      M    M
 20000  -19.9  -3.8   290   43   22   7.1   3.9   19.0  66.2     1.0      M    M
 19500  -18.9  -2.0   290   43   22   7.1   3.9   18.5  65.4     0.6      M    M
 19000  -17.8  -0.0   290   43   22   7.1   3.9   18.1  64.6     0.2      M    M
 18500  -16.7   1.9   295   43   22   8.1   4.4   17.8  64.0    -0.1   1133  5.8
 18000  -15.5   4.1   295   43   22   8.2   4.5   17.5  63.5    -0.4   1082  5.5
 17500  -14.2   6.4   295   43   22   8.2   4.5   17.3  63.1    -0.6   1030  5.2
 17000  -13.1   8.4   300   42   22   7.9   4.3   16.9  62.5    -0.9    980  5.0
 16500  -11.3  11.7   300   42   21   8.0   4.4   16.5  61.7    -1.4    905  4.6
 16000  -10.2  13.6   300   40   21   8.0   4.4   16.2  61.1    -1.7    856  4.3
 15500   -9.0  15.8   300   39   20   8.1   4.4   15.9  60.6    -2.0    806  4.1
 15000   -7.8  18.0   300   37   19   8.4   4.6   15.7  60.2    -2.3    755  3.8
 14500   -6.6  20.1   300   34   18   8.3   4.6   15.4  59.8    -2.5    703  3.6
 14000   -5.3  22.5   300   31   16   8.6   4.7   15.2  59.4    -2.7    651  3.3
 13500   -4.0  24.8   300   28   15   8.6   4.7   15.0  59.0    -2.9    598  3.0
 13000   -2.8  27.0   300   25   13   8.7   4.8   14.9  58.7    -3.1    545  2.8
 12500   -1.5  29.3   305   22   12   8.6   4.7   14.7  58.4    -3.3    491  2.5
 12000   -0.3  31.5   305   19   10   7.4   4.1   14.3  57.8    -3.7    443  2.3
 11750    0.3  32.5   305   18    9   8.4   4.6   14.2  57.5    -3.8    417  2.1
 11500    0.9  33.6   310   17    9   8.3   4.5   14.1  57.3    -4.0    391  2.0
 11250    1.5  34.7   310   16    8   7.6   4.2   13.9  57.1    -4.1    366  1.9
 11000    2.0  35.6   315   16    8   7.3   4.0   13.7  56.7    -4.3    342  1.7
 10750    2.6  36.7   320   16    8   7.8   4.3   13.6  56.5    -4.5    317  1.6
 10500    3.2  37.8   325   16    8   7.9   4.3   13.4  56.2    -4.6    293  1.5
 10250    3.8  38.8   330   16    8   6.8   3.7   13.3  55.9    -4.8    268  1.4
 10000    4.2  39.6   335   16    8   6.7   3.7   13.0  55.4    -5.1    247  1.3
  9750    4.8  40.6   340   16    8   8.4   4.6   12.8  55.1    -5.2    222  1.1
  9500    5.4  41.7   345   16    8   9.4   5.1   12.8  55.0    -5.3    195  1.0
  9250    6.1  43.0   350   16    8   6.9   3.8   12.7  54.9    -5.4    168  0.9
  9000    6.4  43.5   350   16    8   3.7   2.0   12.3  54.2    -5.8    150  0.8
  8750    6.7  44.1   355   16    8   5.4   2.9   11.9  53.4    -6.3    134  0.7
  8500    7.2  45.0   360   17    9   6.7   3.7   11.6  52.9    -6.6    112  0.6
  8250    7.7  45.9   360   18    9   4.0   2.2   11.3  52.4    -6.9     92  0.5
  8000    7.8  46.0   360   18    9  -1.4  -0.8   10.7  51.3    -7.5     81  0.4
  7750    7.9  46.2   360   18    9  10.0   5.5   10.1  50.1    -8.1     70  0.4
  7500    8.9  48.0   360   17    9   6.4   3.5   10.4  50.7    -7.9     32  0.2
  7250    8.1  46.6   355   15    8 -26.3 -14.4    9.1  48.4    -9.2     48  0.2
  7000    5.4  41.7   350   12    6 -39.2 -21.5    6.2  43.1   -12.1    121  0.6
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           04/10/2014 at 0900 MDT          |       04/10/2014 at 1200 MDT
                                           |
K index... +16.3  LI... +0.5               | K index... +16.0  LI... -0.2
CAPE... 0.0  CIN... M                      | CAPE... +8.6  CIN... -34.5
                                           |
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 -59.9 -75.8  285  51 26   2.2   1.2 | -60.8 -77.4  280  53 27   1.5   0.8
 45000 -56.6 -69.9  280  59 31  -0.5  -0.3 | -58.6 -73.5  280  59 31  -0.2  -0.1
 40000 -61.0 -77.8  280  62 32  -2.9  -1.6 | -60.0 -76.0  285  59 31  -0.9  -0.5
 38000 -59.6 -75.3  280  63 32   5.4   2.9 | -58.9 -74.0  285  58 30   4.1   2.2
 36000 -56.4 -69.5  280  65 33   5.4   2.9 | -56.4 -69.5  285  56 29   4.1   2.2
 34000 -52.9 -63.2  280  65 33   7.4   4.0 | -53.6 -64.5  285  54 28   7.3   4.0
 32000 -48.4 -55.1  280  60 31   7.4   4.1 | -48.7 -55.7  290  51 26   7.2   3.9
 30000 -43.9 -47.0  280  55 28   8.2   4.5 | -44.2 -47.6  290  48 25   8.2   4.5
 29000 -41.4 -42.5  280  52 27   8.2   4.5 | -41.7 -43.1  290  47 24   8.2   4.5
 28000 -39.0 -38.2  280  48 25   8.2   4.5 | -39.2 -38.6  290  46 24   8.2   4.5
 27000 -35.9 -32.6  280  45 23   8.2   4.5 | -36.7 -34.1  290  45 23   8.4   4.6
 26000 -33.5 -28.3  285  44 23   8.2   4.5 | -34.2 -29.6  290  44 23   8.4   4.6
 25000 -31.0 -23.8  285  43 22   8.2   4.5 | -31.7 -25.1  290  43 22   8.4   4.6
 24000 -28.6 -19.5  290  42 22   7.3   4.0 | -29.2 -20.6  295  42 22   8.3   4.6
 23000 -26.5 -15.7  290  42 21   7.2   4.0 | -26.7 -16.1  295  41 21   8.3   4.6
 22000 -24.3 -11.7  290  41 21   7.2   4.0 | -24.2 -11.6  295  39 20   8.3   4.6
 21000 -22.2  -8.0  290  41 21   7.0   3.8 | -21.9  -7.4  295  38 20   6.1   3.4
 20000 -20.1  -4.2  290  41 21   7.0   3.9 | -20.0  -4.0  295  39 20   6.4   3.5
 19500 -19.1  -2.4  290  41 21   7.0   3.9 | -19.1  -2.4  295  39 20   6.4   3.5
 19000 -18.0  -0.4  290  41 21   7.0   3.9 | -18.1  -0.6  295  39 20   6.3   3.4
 18500 -17.0   1.4  290  41 21   7.2   4.0 | -17.1   1.2  295  39 20   7.2   4.0
 18000 -15.9   3.4  295  41 21   7.3   4.0 | -16.1   3.0  295  39 20   7.3   4.0
 17500 -14.9   5.2  295  40 21   7.8   4.3 | -15.0   5.0  295  39 20   7.7   4.2
 17000 -13.7   7.3  295  39 20   8.3   4.6 | -13.8   7.2  295  38 20   8.4   4.6
 16500 -12.4   9.7  295  37 19   8.4   4.6 | -12.6   9.3  290  37 19   8.4   4.6
 16000 -11.2  11.8  295  34 18   8.6   4.7 | -10.7  12.7  290  34 17   8.8   4.8
 15500 -10.0  14.0  295  32 16   8.5   4.7 |  -9.4  15.1  290  31 16   8.9   4.9
 15000  -8.7  16.3  295  30 15   9.3   5.1 |  -8.1  17.4  290  28 15   9.1   5.0
 14500  -7.3  18.9  295  28 15   9.3   5.1 |  -6.7  19.9  285  26 13   9.1   5.0
 14000  -5.9  21.4  295  27 14   9.0   4.9 |  -5.4  22.3  285  24 12   9.3   5.1
 13500  -3.9  25.0  290  24 13   8.8   4.8 |  -4.0  24.8  280  22 11   9.4   5.2
 13000  -2.6  27.3  290  22 11   9.1   5.0 |  -2.7  27.1  275  20 10   8.3   4.6
 12500  -1.2  29.8  285  20 10   8.7   4.8 |  -1.4  29.5  270  18  9   8.6   4.7
 12000  -0.0  32.0  280  18  9   8.3   4.5 |  -0.3  31.5  260  16  8   6.4   3.5
 11750   0.6  33.1  275  17  9   8.5   4.6 |   0.2  32.4  255  15  8   6.4   3.5
 11500   1.2  34.2  275  16  8   8.7   4.8 |   0.7  33.3  245  15  8   6.4   3.5
 11250   1.9  35.4  270  15  8   7.4   4.1 |   1.1  34.0  240  15  8   6.3   3.4
 11000   2.4  36.3  275  14  7   6.7   3.7 |   1.6  34.9  235  14  7   5.8   3.2
 10750   2.9  37.2  280  12  6   7.2   4.0 |   2.0  35.6  225  13  7   5.6   3.1
 10500   3.4  38.1  280  11  6   7.6   4.2 |   2.4  36.3  215  12  6   5.9   3.2
 10250   4.0  39.2  285  10  5   5.6   3.1 |   2.8  37.0  205  12  6   5.1   2.8
 10000   4.3  39.7  290   8  4   4.5   2.4 |   3.1  37.6  200  12  6   6.5   3.6
  9750   4.7  40.5  295   7  4   6.2   3.4 |   3.7  38.7  195  11  6   9.4   5.2
  9500   5.1  41.2  305   6  3   6.7   3.7 |   4.5  40.1  190  11  6   9.8   5.3
  9250   5.6  42.1  310   5  3   5.4   3.0 |   5.2  41.4  185  11  6   9.5   5.2
  9000   5.9  42.6  325   5  3   4.3   2.4 |   5.8  42.4  185  12  6   9.3   5.1
  8750   6.2  43.2  335   6  3   3.0   1.6 |   6.5  43.7  185  12  6   9.9   5.5
  8500   6.3  43.3  345   7  4   1.7   0.9 |   7.3  45.1  180  12  6  10.5   5.8
  8250   6.5  43.7  355   8  4   3.1   1.7 |   8.1  46.6  180  12  6  10.5   5.7
  8000   6.7  44.1  355   9  5   2.9   1.6 |   8.9  48.0  180  11  6  11.1   6.1
  7750   6.9  44.4  360   9  5   5.0   2.8 |   9.7  49.5  180  11  6   9.3   5.1
  7500   7.4  45.3  360   9  5   7.8   4.3 |  10.3  50.5  175  11  6  10.0   5.5
  7250   7.9  46.2  360   9  5   7.4   4.1 |  11.2  52.2  175  11  6  13.6   7.5
  7000   8.5  47.3  360   8  4   7.8   4.3 |  12.2  54.0  175  11  5  12.7   7.0
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/10/2014 at 1500 MDT          |       04/10/2014 at 1800 MDT
                                           |
K index... +24.4  LI... -1.9               | K index... +18.2  LI... -1.8
CAPE... +160.8  CIN... -16.3               | CAPE... +164.9  CIN... -6.0
                                           |
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 -60.7 -77.3  285  57 30   1.6   0.9 | -60.6 -77.1  295  47 24   1.8   1.0
 45000 -58.3 -72.9  285  63 32  -0.7  -0.4 | -58.0 -72.4  295  59 30  -0.9  -0.5
 40000 -60.7 -77.3  285  55 28  -1.6  -0.9 | -61.0 -77.8  290  59 30  -2.0  -1.1
 38000 -59.6 -75.3  285  52 27   4.6   2.6 | -59.9 -75.8  290  59 30   5.1   2.8
 36000 -56.8 -70.2  290  49 25   4.7   2.6 | -56.8 -70.2  290  58 30   5.2   2.8
 34000 -53.6 -64.5  290  45 23   7.7   4.2 | -53.4 -64.1  290  56 29   7.4   4.1
 32000 -48.4 -55.1  290  41 21   7.7   4.2 | -48.4 -55.1  290  52 27   7.4   4.1
 30000 -43.7 -46.7  290  39 20   8.0   4.4 | -43.8 -46.8  290  47 24   8.1   4.4
 29000 -41.3 -42.3  290  38 20   8.0   4.4 | -41.4 -42.5  290  45 23   8.1   4.4
 28000 -38.9 -38.0  290  37 19   8.0   4.4 | -38.9 -38.0  290  42 22   8.1   4.4
 27000 -36.5 -33.7  290  37 19   8.0   4.4 | -36.5 -33.7  290  40 21   7.7   4.2
 26000 -34.1 -29.4  290  38 19   8.0   4.4 | -34.2 -29.6  290  39 20   7.8   4.3
 25000 -31.7 -25.1  290  39 20   8.1   4.4 | -31.9 -25.4  290  38 19   7.8   4.3
 24000 -29.3 -20.7  290  39 20   7.6   4.1 | -29.5 -21.1  285  37 19   7.7   4.2
 23000 -27.1 -16.8  290  40 20   7.5   4.1 | -27.2 -17.0  285  37 19   7.7   4.2
 22000 -24.8 -12.6  290  40 21   7.5   4.1 | -24.9 -12.8  285  37 19   7.7   4.3
 21000 -22.6  -8.7  290  40 21   7.2   4.0 | -22.6  -8.7  285  37 19   7.4   4.0
 20000 -20.5  -4.9  285  40 21   7.3   4.0 | -20.4  -4.7  290  36 19   7.4   4.1
 19500 -19.4  -2.9  285  40 21   7.3   4.0 | -19.3  -2.7  290  36 19   7.4   4.1
 19000 -18.3  -0.9  285  40 21   7.2   4.0 | -18.2  -0.8  290  36 18   7.3   4.0
 18500 -17.2   1.0  285  40 21   8.5   4.6 | -17.0   1.4  295  35 18   8.7   4.8
 18000 -16.0   3.2  285  38 20   8.5   4.7 | -15.8   3.6  295  35 18   8.7   4.8
 17500 -14.7   5.5  280  37 19   8.6   4.7 | -14.5   5.9  295  34 18   8.8   4.8
 17000 -13.4   7.9  280  35 18   8.8   4.8 | -13.2   8.2  290  32 17   8.8   4.8
 16500 -12.1  10.2  280  33 17   8.9   4.9 | -11.9  10.6  290  30 16   8.9   4.9
 16000 -10.8  12.6  280  31 16   9.2   5.0 | -10.6  12.9  290  28 14   9.2   5.0
 15500  -8.8  16.2  280  29 15   9.3   5.1 |  -8.6  16.5  285  25 13   9.3   5.1
 15000  -7.4  18.7  280  29 15   9.5   5.2 |  -7.2  19.0  285  24 12   9.5   5.2
 14500  -6.0  21.2  280  28 14   9.5   5.2 |  -5.8  21.6  285  22 12   9.6   5.2
 14000  -4.5  23.9  280  27 14   9.8   5.4 |  -4.4  24.1  290  22 11   9.7   5.3
 13500  -3.1  26.4  280  26 14   9.7   5.3 |  -2.9  26.8  290  21 11   9.5   5.2
 13000  -1.6  29.1  275  25 13   9.6   5.3 |  -1.4  29.5  290  21 11  10.7   5.9
 12500  -0.2  31.6  275  24 12   9.2   5.0 |   0.2  32.4  285  21 11   9.7   5.3
 12000   1.0  33.8  275  22 11   8.1   4.5 |   1.5  34.7  290  20 10   9.4   5.2
 11750   1.7  35.1  270  21 11   8.2   4.5 |   2.2  36.0  290  20 10   9.6   5.3
 11500   2.3  36.1  270  19 10   8.9   4.9 |   2.9  37.2  290  20 10   9.7   5.3
 11250   2.9  37.2  265  18  9   6.1   3.3 |   3.7  38.7  290  19 10   9.2   5.1
 11000   3.2  37.8  260  17  9   6.2   3.4 |   4.3  39.7  285  18  9   9.5   5.2
 10750   3.9  39.0  255  16  8   8.9   4.9 |   5.1  41.2  285  18  9  10.0   5.5
 10500   4.5  40.1  245  15  8   8.8   4.8 |   5.8  42.4  285  18  9  10.3   5.6
 10250   5.1  41.2  240  14  7   6.6   3.6 |   6.6  43.9  285  17  9   8.6   4.7
 10000   5.5  41.9  235  14  7   6.8   3.7 |   7.1  44.8  285  17  9   8.5   4.7
  9750   6.2  43.2  230  13  7  10.2   5.6 |   7.9  46.2  285  16  8  10.5   5.8
  9500   6.9  44.4  225  13  7  10.1   5.5 |   8.6  47.5  285  16  8  10.5   5.7
  9250   7.7  45.9  220  13  7  10.0   5.5 |   9.4  48.9  285  15  8   9.8   5.4
  9000   8.4  47.1  220  13  7   9.9   5.4 |  10.1  50.2  285  15  8   9.0   5.0
  8750   9.2  48.6  220  13  7  10.1   5.5 |  10.8  51.4  285  15  7   9.9   5.4
  8500   9.9  49.8  215  13  6  10.2   5.6 |  11.6  52.9  285  14  7  10.3   5.7
  8250  10.7  51.3  215  13  6  10.2   5.6 |  12.3  54.1  285  14  7   9.8   5.4
  8000  11.4  52.5  210  12  6  10.5   5.8 |  13.0  55.4  285  13  7   9.6   5.3
  7750  12.2  54.0  210  12  6   9.4   5.2 |  13.8  56.8  285  13  6   9.4   5.1
  7500  12.9  55.2  205  12  6   9.0   4.9 |  14.4  57.9  280  11  6   7.7   4.2
  7250  13.6  56.5  205  11  6  10.7   5.9 |  14.8  58.6  280  10  5   5.4   3.0
  7000  14.4  57.9  205  11  6  11.1   6.1 |  15.1  59.2  280   9  5   4.1   2.3
  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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