Soaring Guidance
Issued by NWS Pueblo, CO

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UXUS97 KPUB 201016
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0416 MDT Sunday, April 20, 2014

This forecast is for Sunday, April 20, 2014:

If the trigger temperature of 53.8 F/12.1 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 541 ft/min (2.7 m/s)
   Maximum height of thermals.................. 15228 ft MSL (8470 ft AGL)

Forecast maximum temperature................... 61.0 F/16.6 C
Time of trigger temperature.................... 0900 MDT
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................. 11528 ft MSL (4770 ft AGL)
Thermal soaring outlook for Monday 04/21....... 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....................... 16604 ft MSL (9846 ft AGL)
Wave soaring outlook for Monday 04/21.......... Poor

Remarks...

Sunrise/Sunset.................... 06:15:23 / 19:40:08 MDT
Total possible sunshine........... 13 hr 24 min 44 sec (804 min 44 sec)
Altitude of sun at 12:57:55 MDT... 62.73 degrees

Upper air data from numerical model forecast valid on 04/20/2014 at 0600 MDT

Freezing level.................. 11526 ft MSL (4768 ft AGL)
Convective condensation level... 11526 ft MSL (4768 ft AGL)
Lifted condensation level....... 12395 ft MSL (5637 ft AGL)
Lifted index.................... -2.6
K index......................... +26.5

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   255   20   10   2.1   1.1      M     M       M      M    M
 45000  -57.0 -70.6   250   20   10  -4.5  -2.5      M     M       M      M    M
 40000  -62.8 -81.0   190   31   16  -3.9  -2.1      M     M       M      M    M
 38000  -60.8 -77.4   185   31   16   7.3   4.0      M     M       M      M    M
 36000  -56.4 -69.5   175   28   15   7.3   4.0      M     M       M      M    M
 34000  -51.8 -61.2   175   25   13   8.5   4.7      M     M       M      M    M
 32000  -46.7 -52.1   185   19   10   8.5   4.7      M     M       M      M    M
 30000  -41.0 -41.8   205   12    6   8.2   4.5   28.4  83.2     9.5      M    M
 29000  -38.5 -37.3   210    8    4   8.3   4.5   27.8  82.1     9.1      M    M
 28000  -36.1 -33.0   225    4    2   8.3   4.5   27.3  81.2     8.8      M    M
 27000  -33.6 -28.5   270    2    1   8.6   4.7   26.8  80.3     8.5      M    M
 26000  -31.0 -23.8   295    3    2   8.5   4.7   26.3  79.3     8.2      M    M
 25000  -28.4 -19.1   310    4    2   8.5   4.7   25.9  78.6     8.0      M    M
 24000  -25.9 -14.6   315    6    3   7.5   4.1   25.4  77.8     7.7      M    M
 23000  -23.7 -10.7   315    6    3   7.6   4.2   24.6  76.2     7.0      M    M
 22000  -21.4  -6.5   315    7    4   7.6   4.2   23.8  74.9     6.5      M    M
 21000  -19.3  -2.7   320    9    5   6.7   3.7   23.0  73.5     5.8      M    M
 20000  -17.3   0.9   335   11    6   6.8   3.7   22.0  71.5     4.9      M    M
 19500  -16.3   2.7   340   13    6   6.9   3.8   21.5  70.6     4.5      M    M
 19000  -15.3   4.5   340   14    7   7.0   3.8   21.0  69.8     4.1      M    M
 18500  -14.3   6.3   345   15    8   5.9   3.2   20.5  68.9     3.6      M    M
 18000  -13.5   7.7   350   15    8   5.9   3.2   19.8  67.7     3.0      M    M
 17500  -12.6   9.3   360   15    8   6.0   3.3   19.2  66.5     2.4      M    M
 17000  -11.7  10.9   005   16    8   6.1   3.3   18.6  65.4     1.8      M    M
 16500  -10.9  12.4   010   17    9   6.1   3.3   18.0  64.3     1.3      M    M
 16000   -9.9  14.2   010   17    9   7.2   4.0   17.4  63.4     0.8      M    M
 15500   -8.9  16.0   015   17    9   7.1   3.9   17.0  62.6     0.3      M    M
 15000   -7.3  18.9   015   17    9   7.8   4.3   16.4  61.6    -0.3    708  3.6
 14500   -6.1  21.0   015   16    8   7.8   4.3   16.1  61.0    -0.6    659  3.3
 14000   -5.0  23.0   020   15    8   7.8   4.3   15.8  60.5    -0.9    611  3.1
 13500   -3.9  25.0   025   13    7   7.9   4.3   15.5  59.9    -1.3    562  2.9
 13000   -2.8  27.0   030   13    7   7.6   4.2   15.2  59.3    -1.6    514  2.6
 12500   -1.7  28.9   035   13    7   7.3   4.0   14.9  58.7    -2.0    466  2.4
 12000   -0.8  30.6   040   13    7   6.2   3.4   14.3  57.7    -2.6    425  2.2
 11750   -0.3  31.5   035   13    7   7.1   3.9   14.1  57.3    -2.9    403  2.0
 11500    0.2  32.4   035   14    7   7.3   4.0   13.8  56.9    -3.1    381  1.9
 11250    0.7  33.3   035   14    7   5.6   3.1   13.6  56.5    -3.3    358  1.8
 11000    1.0  33.8   035   14    7   5.8   3.2   13.2  55.8    -3.7    340  1.7
 10750    1.6  34.9   030   14    7   7.7   4.2   13.1  55.5    -3.9    317  1.6
 10500    2.1  35.8   030   14    7   7.4   4.1   12.9  55.2    -4.1    293  1.5
 10250    2.6  36.7   030   13    7   6.8   3.7   12.7  54.8    -4.3    270  1.4
 10000    3.1  37.6   025   13    7   6.4   3.5   12.4  54.4    -4.6    249  1.3
  9750    3.6  38.5   020   13    7   7.2   4.0   12.2  54.0    -4.8    226  1.1
  9500    4.2  39.6   020   13    6   7.4   4.1   12.0  53.6    -5.0    202  1.0
  9250    4.7  40.5   015   12    6   7.1   3.9   11.8  53.3    -5.2    179  0.9
  9000    5.2  41.4   010   12    6   6.7   3.7   11.6  52.9    -5.4    156  0.8
  8750    5.7  42.3   005   12    6   7.4   4.1   11.4  52.5    -5.7    133  0.7
  8500    6.3  43.3   360   13    6   7.7   4.2   11.3  52.3    -5.8    107  0.5
  8250    6.9  44.4   355   13    7   5.5   3.0   11.0  51.9    -6.0     84  0.4
  8000    7.2  45.0   355   13    7   3.0   1.6   10.6  51.1    -6.5     68  0.3
  7750    7.5  45.5   350   13    7   6.6   3.6   10.2  50.3    -6.9     52  0.3
  7500    8.0  46.4   345   13    7   4.3   2.4   10.0  50.0    -7.2     29  0.1
  7250    7.9  46.2   340   11    6  -5.1  -2.8    9.5  49.1    -7.7     24  0.1
  7000    7.4  45.3   335    9    5  -5.9  -3.2    8.7  47.7    -8.5     32  0.2
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           04/20/2014 at 0900 MDT          |       04/20/2014 at 1200 MDT
                                           |
K index... +23.9  LI... +0.2               | K index... +20.8  LI... -0.1
CAPE... +51.2  CIN... -5.6                 | CAPE... +24.2  CIN... -10.9
                                           |
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 -59.5 -75.1  255  17  9   1.9   1.0 | -59.7 -75.5  265  17  9   1.8   1.0
 45000 -56.9 -70.4  260  16  8  -3.5  -1.9 | -57.4 -71.3  275  15  8  -2.4  -1.3
 40000 -61.5 -78.7  210  21 11  -3.0  -1.7 | -60.4 -76.7  255  15  7  -2.0  -1.1
 38000 -59.8 -75.6  200  19 10   5.8   3.2 | -58.9 -74.0  250  12  6   4.9   2.7
 36000 -56.3 -69.3  185  15  8   5.8   3.2 | -56.0 -68.8  245   8  4   4.9   2.7
 34000 -52.3 -62.1  175  11  5   8.7   4.8 | -51.6 -60.9  255   7  3   8.8   4.8
 32000 -46.4 -51.5  220   7  3   8.7   4.8 | -46.3 -51.3  285  10  5   8.8   4.8
 30000 -41.1 -42.0  265   5  2   8.8   4.8 | -41.0 -41.8  300  11  6   8.8   4.8
 29000 -38.5 -37.3  310   3  1   8.8   4.8 | -38.4 -37.1  305  10  5   8.8   4.8
 28000 -35.9 -32.6  005   4  2   8.8   4.8 | -35.7 -32.3  315   9  5   8.8   4.8
 27000 -33.3 -27.9  015   6  3   8.3   4.5 | -33.1 -27.6  320   9  5   8.8   4.8
 26000 -30.8 -23.4  360   7  4   8.3   4.5 | -30.4 -22.7  320  10  5   8.8   4.8
 25000 -28.3 -18.9  350   8  4   8.3   4.6 | -27.8 -18.0  320  12  6   8.8   4.8
 24000 -25.9 -14.6  345  10  5   7.7   4.2 | -25.3 -13.5  325  12  6   7.5   4.1
 23000 -23.5 -10.3  340  11  6   7.7   4.2 | -23.0  -9.4  330  13  7   7.6   4.2
 22000 -21.2  -6.2  335  13  7   7.7   4.2 | -20.7  -5.3  330  14  7   7.6   4.2
 21000 -19.0  -2.2  335  15  8   7.1   3.9 | -18.6  -1.5  340  14  7   5.6   3.1
 20000 -16.9   1.6  345  16  8   7.2   3.9 | -17.0   1.4  350  14  7   5.8   3.2
 19500 -15.8   3.6  345  16  8   7.2   4.0 | -16.1   3.0  355  14  7   5.9   3.2
 19000 -14.8   5.4  350  17  9   7.6   4.2 | -15.3   4.5  360  15  7   6.0   3.3
 18500 -13.9   7.0  355  17  9   4.4   2.4 | -14.5   5.9  005  14  7   5.4   2.9
 18000 -13.2   8.2  360  16  8   4.6   2.5 | -13.7   7.3  010  13  7   5.5   3.0
 17500 -12.6   9.3  010  16  8   5.2   2.9 | -12.9   8.8  015  13  7   5.9   3.2
 17000 -11.8  10.8  015  16  8   5.9   3.2 | -12.0  10.4  015  12  6   6.3   3.5
 16500 -10.9  12.4  025  16  8   5.9   3.3 | -11.1  12.0  020  12  6   6.4   3.5
 16000 -10.0  14.0  025  16  8   7.0   3.8 |  -9.5  14.9  020  13  6   7.5   4.1
 15500  -8.5  16.7  030  16  8   7.0   3.9 |  -8.4  16.9  020  13  7   7.7   4.2
 15000  -7.4  18.7  030  16  8   7.3   4.0 |  -7.3  18.9  020  13  7   8.0   4.4
 14500  -6.4  20.5  030  15  8   7.3   4.0 |  -6.1  21.0  015  14  7   8.0   4.4
 14000  -5.3  22.5  030  15  7   8.0   4.4 |  -5.0  23.0  015  15  8   7.5   4.1
 13500  -4.1  24.6  030  14  7   7.9   4.4 |  -3.9  25.0  010  16  8   7.7   4.2
 13000  -3.0  26.6  030  14  7   8.3   4.5 |  -2.8  27.0  010  17  9   6.5   3.6
 12500  -1.8  28.8  030  14  7   7.9   4.3 |  -1.8  28.8  005  19 10   6.0   3.3
 12000  -0.7  30.7  025  14  7   7.5   4.1 |  -1.0  30.2  360  22 11   6.2   3.4
 11750  -0.1  31.8  020  14  7   8.0   4.4 |  -0.5  31.1  360  23 12   6.8   3.7
 11500   0.4  32.7  020  15  8   8.0   4.4 |  -0.0  32.0  360  24 12   6.8   3.7
 11250   1.0  33.8  015  15  8   7.3   4.0 |   0.5  32.9  360  25 13   6.4   3.5
 11000   1.6  34.9  015  15  8   7.2   3.9 |   1.0  33.8  360  25 13   7.2   3.9
 10750   2.1  35.8  010  16  8   7.8   4.3 |   1.5  34.7  360  25 13   8.1   4.4
 10500   2.7  36.9  005  17  9   7.9   4.4 |   2.1  35.8  360  25 13   8.1   4.4
 10250   3.3  37.9  005  17  9   6.8   3.7 |   2.7  36.9  360  25 13   7.2   3.9
 10000   3.8  38.8  360  18  9   6.2   3.4 |   3.2  37.8  360  24 12   7.9   4.4
  9750   4.3  39.7  355  19 10   7.2   3.9 |   3.8  38.8  360  23 12  10.3   5.7
  9500   4.8  40.6  355  20 10   7.5   4.1 |   4.6  40.3  360  22 12  10.6   5.8
  9250   5.4  41.7  350  21 11   6.6   3.6 |   5.4  41.7  360  22 11   9.7   5.3
  9000   5.8  42.4  350  21 11   5.8   3.2 |   6.0  42.8  360  21 11   8.9   4.9
  8750   6.3  43.3  345  21 11   7.5   4.1 |   6.7  44.1  360  21 11  10.3   5.7
  8500   6.9  44.4  345  22 11   8.6   4.7 |   7.6  45.7  360  21 11  11.1   6.1
  8250   7.4  45.3  345  21 11   7.9   4.3 |   8.4  47.1  360  20 11  10.6   5.8
  8000   8.0  46.4  345  20 10   7.5   4.1 |   9.1  48.4  360  20 10  10.7   5.9
  7750   8.5  47.3  340  18  9   8.2   4.5 |   9.9  49.8  360  19 10  10.2   5.6
  7500   9.2  48.6  340  17  9   8.5   4.6 |  10.7  51.3  360  19 10  10.6   5.8
  7250   9.7  49.5  345  15  8   7.6   4.2 |  11.5  52.7  360  18  9  11.8   6.5
  7000  10.3  50.5  345  13  7   7.8   4.3 |  12.3  54.1  360  17  9  11.3   6.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/20/2014 at 1500 MDT          |       04/20/2014 at 1800 MDT
                                           |
K index... +17.7  LI... -0.3               | K index... +17.5  LI... -1.2
CAPE... +28.6  CIN... -9.5                 | CAPE... +83.1  CIN... -6.4
                                           |
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 -59.7 -75.5  265  20 10   1.1   0.6 | -60.3 -76.5  270  23 12   1.5   0.8
 45000 -58.3 -72.9  275  16  8  -1.8  -1.0 | -58.4 -73.1  285  22 11  -2.3  -1.3
 40000 -60.7 -77.3  305  16  8  -1.6  -0.9 | -61.5 -78.7  325  23 12  -2.0  -1.1
 38000 -58.9 -74.0  295  16  8   5.4   3.0 | -59.1 -74.4  330  24 13   6.8   3.7
 36000 -55.6 -68.1  275  18  9   5.4   3.0 | -55.0 -67.0  330  24 12   6.8   3.7
 34000 -51.1 -60.0  265  20 11   8.8   4.8 | -50.7 -59.3  330  24 12   7.7   4.2
 32000 -45.8 -50.4  270  21 11   8.8   4.8 | -45.5 -49.9  325  22 11   7.7   4.2
 30000 -40.7 -41.3  275  19 10   8.2   4.5 | -40.8 -41.4  320  20 10   8.1   4.4
 29000 -38.2 -36.8  280  17  9   8.2   4.5 | -38.3 -36.9  320  20 10   8.1   4.4
 28000 -35.7 -32.3  280  15  8   8.2   4.5 | -35.9 -32.6  315  19 10   8.1   4.4
 27000 -33.2 -27.8  285  14  7   8.5   4.7 | -33.5 -28.3  315  19 10   8.4   4.6
 26000 -30.7 -23.3  290  14  7   8.5   4.7 | -31.0 -23.8  315  19 10   8.4   4.6
 25000 -28.1 -18.6  295  13  7   8.5   4.7 | -28.4 -19.1  315  18 10   8.4   4.6
 24000 -25.7 -14.3  305  13  7   6.9   3.8 | -26.0 -14.8  315  18  9   7.2   3.9
 23000 -23.5 -10.3  315  13  7   7.1   3.9 | -23.9 -11.0  320  18  9   7.3   4.0
 22000 -21.4  -6.5  325  13  7   7.2   3.9 | -21.7  -7.1  320  18  9   7.3   4.0
 21000 -19.3  -2.7  335  14  7   7.0   3.8 | -19.6  -3.3  325  18  9   6.6   3.6
 20000 -17.2   1.0  345  15  8   7.1   3.9 | -17.6   0.3  330  20 10   6.6   3.6
 19500 -16.2   2.8  350  15  8   7.1   3.9 | -16.6   2.1  330  20 10   6.6   3.6
 19000 -15.2   4.6  355  16  8   7.3   4.0 | -15.6   3.9  330  21 11   6.7   3.7
 18500 -14.2   6.4  355  17  9   5.3   2.9 | -14.7   5.5  335  22 11   6.7   3.7
 18000 -13.4   7.9  355  17  9   5.5   3.0 | -13.7   7.3  340  22 11   6.7   3.7
 17500 -12.6   9.3  350  18  9   6.4   3.5 | -12.7   9.1  340  23 12   6.9   3.8
 17000 -11.6  11.1  350  18  9   7.0   3.8 | -11.6  11.1  345  23 12   7.1   3.9
 16500 -10.5  13.1  345  18  9   7.1   3.9 | -10.6  12.9  345  22 12   7.1   3.9
 16000  -8.9  16.0  345  19 10   7.5   4.1 |  -8.9  16.0  350  22 11   7.4   4.1
 15500  -7.8  18.0  345  19 10   7.5   4.1 |  -7.8  18.0  350  22 11   7.5   4.1
 15000  -6.7  19.9  350  20 10   7.4   4.1 |  -6.7  19.9  350  22 11   7.6   4.2
 14500  -5.6  21.9  350  21 11   7.4   4.1 |  -5.6  21.9  350  21 11   7.6   4.2
 14000  -4.5  23.9  350  22 11   7.0   3.8 |  -4.4  24.1  350  21 11   7.8   4.3
 13500  -3.5  25.7  355  23 12   7.0   3.8 |  -3.3  26.1  350  21 11   7.8   4.3
 13000  -2.5  27.5  355  23 12   6.7   3.7 |  -2.1  28.2  345  20 10   8.4   4.6
 12500  -1.5  29.3  360  23 12   6.6   3.6 |  -0.9  30.4  345  19 10   8.1   4.4
 12000  -0.6  30.9  360  23 12   6.6   3.6 |   0.1  32.2  345  18  9   7.9   4.3
 11750  -0.1  31.8  360  21 11   6.9   3.8 |   0.7  33.3  350  17  9   8.1   4.4
 11500   0.3  32.5  005  20 10   6.4   3.5 |   1.2  34.2  350  16  8   7.8   4.3
 11250   0.8  33.4  005  19 10   8.6   4.7 |   1.7  35.1  350  15  7   9.3   5.1
 11000   1.5  34.7  005  19 10  10.1   5.6 |   2.5  36.5  350  15  8  10.3   5.7
 10750   2.2  36.0  005  19 10   9.1   5.0 |   3.2  37.8  355  14  7   9.5   5.2
 10500   2.8  37.0  010  18  9   9.6   5.3 |   4.0  39.2  355  14  7   9.9   5.4
 10250   3.5  38.3  010  18  9   8.7   4.8 |   4.7  40.5  355  14  7   9.0   5.2
 10000   4.1  39.4  010  18  9   9.2   5.0 |   5.3  41.5  355  14  7   9.1   5.0
  9750   4.9  40.8  010  18  9  10.7   5.8 |   6.1  43.0  355  14  7  10.2   5.6
  9500   5.7  42.3  010  18  9  10.7   5.9 |   6.8  44.2  355  14  7  10.2   5.6
  9250   6.5  43.7  010  18  9   9.7   5.3 |   7.6  45.7  355  14  7   9.7   5.3
  9000   7.2  45.0  010  17  9   9.0   4.9 |   8.3  46.9  355  14  7   9.4   5.2
  8750   7.9  46.2  010  17  9  10.2   5.6 |   9.0  48.2  355  13  7  10.2   5.6
  8500   8.7  47.7  010  17  9  10.8   5.9 |   9.8  49.6  355  13  7  10.6   5.8
  8250   9.5  49.1  010  17  9  10.3   5.7 |  10.6  51.1  355  13  7  10.1   5.5
  8000  10.2  50.4  010  17  9  10.5   5.8 |  11.3  52.3  355  13  7  10.2   5.6
  7750  11.0  51.8  010  16  8   9.7   5.3 |  12.0  53.6  355  13  6   9.3   5.1
  7500  11.7  53.1  015  16  8   9.8   5.4 |  12.7  54.9  360  12  6   8.3   4.6
  7250  12.5  54.5  015  15  8  11.0   6.0 |  13.3  55.9  360  12  6   8.6   4.7
  7000  13.2  55.8  015  14  7  10.4   5.7 |  13.9  57.0  360  11  6   8.4   4.6
  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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