Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 131018
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0417 MDT Saturday, September 13, 2014

This forecast is for Saturday, September 13, 2014:

If the trigger temperature of 68.5 F/20.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 639 ft/min (3.2 m/s)
   Maximum height of thermals.................. 13870 ft MSL (7112 ft AGL)

Forecast maximum temperature................... 72.0 F/22.7 C
Time of trigger temperature.................... 1145 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................. 9245 ft MSL (2488 ft AGL)
Thermal soaring outlook for Sunday 09/14....... Excellent

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....................... 15608 ft MSL (8850 ft AGL)
Wave soaring outlook for Sunday 09/14.......... Poor

Remarks...

Sunrise/Sunset.................... 06:38:37 / 19:11:56 MDT
Total possible sunshine........... 12 hr 33 min 19 sec (753 min 19 sec)
Altitude of sun at 12:54:47 MDT... 54.66 degrees

Upper air data from numerical model forecast valid on 09/13/2014 at 0600 MDT

Freezing level.................. 14731 ft MSL (7973 ft AGL)
Convective condensation level... 20572 ft MSL (13814 ft AGL)
Lifted condensation level....... 18207 ft MSL (11449 ft AGL)
Lifted index.................... +4.4
K index......................... -21.7

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  -65.3 -85.5   275   40   21   2.6   1.4      M     M       M      M    M
 45000  -61.0 -77.8   275   57   29   3.9   2.1      M     M       M      M    M
 40000  -54.7 -66.5   270   61   32   6.4   3.5      M     M       M      M    M
 38000  -51.0 -59.8   270   57   29   6.2   3.4      M     M       M      M    M
 36000  -47.3 -53.1   275   52   27   6.2   3.4      M     M       M      M    M
 34000  -42.6 -44.7   275   50   26   8.4   4.6      M     M       M      M    M
 32000  -37.6 -35.7   275   47   24   8.4   4.6      M     M       M      M    M
 30000  -32.8 -27.0   275   44   22   7.7   4.2   37.8 100.0    12.0      M    M
 29000  -29.9 -21.8   280   41   21   7.7   4.2   36.9  98.3    11.5      M    M
 28000  -27.6 -17.7   285   40   20   7.4   4.1   36.2  97.2    11.1      M    M
 27000  -25.5 -13.9   285   37   19   6.9   3.8   35.1  95.1    10.3      M    M
 26000  -23.5 -10.3   285   35   18   6.9   3.8   34.0  93.2     9.6      M    M
 25000  -21.4  -6.5   280   32   17   7.0   3.8   33.1  91.5     8.9      M    M
 24000  -19.3  -2.7   280   30   16   6.8   3.7   32.0  89.5     8.1      M    M
 23000  -17.3   0.9   275   28   15   6.8   3.7   30.9  87.6     7.3      M    M
 22000  -15.3   4.5   275   26   14   6.9   3.8   29.9  85.8     6.5      M    M
 21000  -13.5   7.7   275   25   13   5.6   3.1   28.5  83.3     5.4      M    M
 20000  -11.8  10.8   275   23   12   5.7   3.1   27.1  80.7     4.2      M    M
 19500  -11.0  12.2   275   22   11   5.6   3.1   26.4  79.5     3.6      M    M
 19000  -10.1  13.8   275   21   11   6.9   3.8   25.8  78.5     3.1      M    M
 18500   -9.0  15.8   275   19   10   7.4   4.0   25.4  77.7     2.8      M    M
 18000   -7.9  17.8   275   18   10   7.5   4.1   25.0  77.0     2.4      M    M
 17500   -6.7  19.9   275   18    9   8.2   4.5   24.7  76.4     2.2      M    M
 17000   -5.5  22.1   280   18    9   8.2   4.5   24.4  76.0     1.9      M    M
 16500   -4.3  24.3   280   18    9   7.5   4.1   24.1  75.4     1.7      M    M
 16000   -3.2  26.2   275   19   10   7.3   4.0   23.7  74.7     1.3      M    M
 15500   -2.1  28.2   275   19   10   7.5   4.1   23.3  74.0     1.0      M    M
 15000   -0.9  30.4   275   20   10   7.9   4.4   23.0  73.4     0.7      M    M
 14500    0.9  33.6   275   20   10   8.0   4.4   22.6  72.6     0.3      M    M
 14000    2.0  35.6   275   21   11   8.0   4.4   22.3  72.1     0.0      M    M
 13500    3.2  37.8   275   21   11   8.0   4.4   22.0  71.7    -0.2    590  3.0
 13000    4.4  39.9   280   21   11   7.9   4.3   21.7  71.1    -0.6    541  2.7
 12500    5.6  42.1   280   22   11   8.5   4.6   21.4  70.6    -0.9    491  2.5
 12000    6.8  44.2   280   22   11   7.6   4.2   21.2  70.1    -1.1    441  2.2
 11750    7.3  45.1   280   22   11   7.9   4.3   21.0  69.9    -1.3    416  2.1
 11500    7.9  46.2   280   22   11   7.7   4.2   20.9  69.6    -1.5    392  2.0
 11250    8.5  47.3   280   22   11   8.1   4.4   20.7  69.3    -1.6    367  1.9
 11000    9.1  48.4   280   21   11   8.8   4.8   20.6  69.1    -1.8    342  1.7
 10750    9.7  49.5   280   21   11   9.2   5.1   20.6  69.0    -1.9    316  1.6
 10500   10.3  50.5   280   21   11   8.7   4.8   20.5  68.9    -2.0    289  1.5
 10250   10.9  51.6   280   21   11   6.0   3.3   20.4  68.6    -2.2    266  1.4
 10000   11.3  52.3   280   20   10   7.1   3.9   20.1  68.1    -2.5    247  1.3
  9750   11.9  53.4   280   20   10  10.7   5.9   20.0  68.0    -2.6    219  1.1
  9500   12.7  54.9   275   19   10   7.6   4.2   20.0  68.1    -2.6    190  1.0
  9250   12.9  55.2   275   19   10   1.2   0.7   19.6  67.3    -3.1    174  0.9
  9000   12.9  55.2   270   18    9  -1.4  -0.8   18.8  65.9    -3.9    169  0.9
  8750   12.9  55.2   270   18    9   6.0   3.3   18.2  64.7    -4.6    161  0.8
  8500   13.3  55.9   265   17    9  -1.6  -0.9   17.9  64.2    -4.9    141  0.7
  8250   12.4  54.3   260   16    8 -17.6  -9.7   16.2  61.2    -6.6    162  0.8
  8000   11.0  51.8   250   15    8 -17.5  -9.6   14.1  57.4    -8.7    196  1.0
  7750    9.6  49.3   240   15    7 -19.7 -10.8   12.0  53.7   -10.9    231  1.2
  7500    7.8  46.0   230   16    8 -26.1 -14.3    9.6  49.3   -13.4    276  1.4
  7250    5.7  42.3   225   13    7 -28.8 -15.8    7.2  44.9   -15.8    332  1.7
  7000    3.6  38.5   225   10    5 -27.0 -14.8    4.7  40.5   -18.3    388  2.0
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           09/13/2014 at 0900 MDT          |       09/13/2014 at 1200 MDT
                                           |
K index... -17.1  LI... +3.2               | K index... -4.6  LI... +2.5
CAPE... 0.0  CIN... -4.5                   | 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 -65.1 -85.2  275  44 23   3.6   2.0 | -65.2 -85.4  275  45 23   3.6   2.0
 45000 -59.7 -75.5  280  57 30   3.0   1.7 | -59.8 -75.6  280  57 29   3.1   1.7
 40000 -54.9 -66.8  270  58 30   6.7   3.7 | -54.9 -66.8  270  56 29   6.5   3.6
 38000 -51.1 -60.0  270  54 28   6.3   3.4 | -51.1 -60.0  265  50 26   6.2   3.4
 36000 -47.4 -53.3  265  49 25   6.3   3.5 | -47.4 -53.3  255  45 23   6.2   3.4
 34000 -42.8 -45.0  270  45 23   8.0   4.4 | -42.8 -45.0  260  43 22   8.2   4.5
 32000 -38.0 -36.4  270  42 22   8.1   4.4 | -37.9 -36.2  270  44 22   8.2   4.5
 30000 -32.8 -27.0  270  36 19   7.6   4.2 | -32.7 -26.9  275  38 20   7.5   4.1
 29000 -30.5 -22.9  275  34 17   7.6   4.2 | -30.4 -22.7  275  35 18   7.5   4.1
 28000 -28.3 -18.9  275  31 16   7.6   4.2 | -28.2 -18.8  275  31 16   7.4   4.1
 27000 -26.0 -14.8  275  29 15   7.6   4.2 | -26.0 -14.8  275  29 15   7.3   4.0
 26000 -23.7 -10.7  275  28 15   7.6   4.2 | -23.8 -10.8  275  28 14   7.3   4.0
 25000 -21.4  -6.5  280  27 14   7.7   4.2 | -21.7  -7.1  275  26 13   7.4   4.1
 24000 -19.3  -2.7  280  27 14   6.6   3.6 | -19.7  -3.5  275  26 13   6.2   3.4
 23000 -17.3   0.9  275  27 14   6.6   3.6 | -17.8  -0.0  275  26 14   6.3   3.4
 22000 -15.3   4.5  275  27 14   6.7   3.7 | -15.9   3.4  275  27 14   6.3   3.4
 21000 -13.6   7.5  275  26 13   5.7   3.1 | -14.1   6.6  280  26 14   6.2   3.4
 20000 -11.9  10.6  275  24 12   5.7   3.1 | -12.2  10.0  280  26 13   6.2   3.4
 19500 -11.0  12.2  275  23 12   5.7   3.1 | -11.3  11.7  280  25 13   6.2   3.4
 19000 -10.1  13.8  280  23 12   6.8   3.7 | -10.3  13.5  280  25 13   6.7   3.7
 18500  -9.1  15.6  280  22 11   7.2   3.9 |  -9.3  15.3  285  24 13   6.9   3.8
 18000  -8.0  17.6  280  21 11   7.3   4.0 |  -8.3  17.1  290  24 12   7.0   3.9
 17500  -6.8  19.8  280  21 11   8.1   4.4 |  -7.2  19.0  295  23 12   7.9   4.3
 17000  -5.6  21.9  285  21 11   8.1   4.4 |  -6.0  21.2  300  23 12   7.9   4.3
 16500  -4.4  24.1  290  20 10   8.0   4.4 |  -4.8  23.4  305  23 12   8.0   4.4
 16000  -3.2  26.2  290  20 10   8.0   4.4 |  -3.6  25.5  310  23 12   8.0   4.4
 15500  -2.0  28.4  295  20 10   7.8   4.3 |  -2.4  27.7  310  24 12   8.2   4.5
 15000  -0.3  31.5  300  19 10   7.4   4.1 |  -1.2  29.8  315  25 13   8.4   4.6
 14500   0.8  33.4  305  19 10   7.4   4.1 |   0.7  33.3  315  26 13   7.7   4.2
 14000   1.9  35.4  310  20 10   7.4   4.1 |   1.8  35.2  315  27 14   7.5   4.1
 13500   3.0  37.4  310  21 11   7.4   4.1 |   2.9  37.2  315  28 14   7.4   4.0
 13000   4.1  39.4  315  22 11   7.4   4.1 |   3.9  39.0  315  26 13   7.4   4.1
 12500   5.1  41.2  315  24 12   8.1   4.4 |   4.9  40.8  315  24 12   7.8   4.3
 12000   6.3  43.3  310  26 13   7.0   3.9 |   6.1  43.0  310  20 10   9.2   5.0
 11750   6.8  44.2  310  27 14   7.0   3.8 |   6.8  44.2  310  18  9   8.9   4.9
 11500   7.3  45.1  310  27 14   8.1   4.4 |   7.4  45.3  310  16  8   9.6   5.2
 11250   7.9  46.2  310  27 14   8.7   4.8 |   8.2  46.8  310  15  8   9.9   5.4
 11000   8.5  47.3  305  27 14   7.4   4.0 |   8.9  48.0  310  14  7   9.5   5.2
 10750   9.0  48.2  305  26 13   6.8   3.7 |   9.6  49.3  315  14  7   9.4   5.2
 10500   9.5  49.1  305  25 13   7.7   4.2 |  10.3  50.5  315  13  7   9.6   5.3
 10250  10.1  50.2  305  24 13   9.6   5.3 |  11.0  51.8  315  13  7   9.9   5.4
 10000  10.8  51.4  305  23 12   9.7   5.3 |  11.7  53.1  315  12  6   9.8   5.4
  9750  11.5  52.7  305  23 12   9.4   5.1 |  12.5  54.5  315  12  6   9.9   5.4
  9500  12.2  54.0  300  22 11   8.9   4.9 |  13.2  55.8  315  11  6   9.3   5.1
  9250  12.9  55.2  300  21 11   8.1   4.5 |  13.8  56.8  315  11  5   8.5   4.7
  9000  13.4  56.1  300  20 10   7.7   4.2 |  14.5  58.1  315  10  5   8.8   4.8
  8750  14.1  57.4  300  20 10  12.0   6.6 |  15.2  59.4  315   9  5  10.7   5.9
  8500  15.0  59.0  300  19 10   5.3   2.9 |  16.0  60.8  315   9  5  10.9   6.0
  8250  14.8  58.6  300  17  9  -3.9  -2.1 |  16.8  62.2  315   8  4  10.0   5.5
  8000  14.5  58.1  295  15  8  -4.4  -2.4 |  17.5  63.5  315   8  4  10.2   5.6
  7750  14.2  57.6  290  14  7   1.9   1.1 |  18.3  64.9  315   7  4  10.4   5.7
  7500  14.4  57.9  280  12  6   0.6   0.3 |  19.1  66.4  320   7  3  11.2   6.2
  7250  13.9  57.0  275  10  5  -8.9  -4.9 |  19.9  67.8  320   6  3  11.6   6.4
  7000  13.4  56.1  265   7  4  -1.0  -0.6 |  20.8  69.4  320   6  3  11.4   6.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/13/2014 at 1500 MDT          |       09/13/2014 at 1800 MDT
                                           |
K index... +12.2  LI... +0.7               | K index... +19.8  LI... -1.2
CAPE... 0.0  CIN... M                      | CAPE... +41.3  CIN... -92.7
                                           |
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 -65.5 -85.9  270  54 28   4.2   2.3 | -66.5 -87.7  270  51 26   3.6   2.0
 45000 -59.0 -74.2  275  62 32   3.8   2.1 | -59.9 -75.8  275  58 30   5.6   3.1
 40000 -53.3 -63.9  270  55 28   4.5   2.5 | -51.6 -60.9  275  52 27   3.0   1.7
 38000 -50.7 -59.3  265  56 29   4.5   2.4 | -49.7 -57.5  275  50 26   3.3   1.8
 36000 -48.0 -54.4  265  57 29   4.6   2.5 | -47.7 -53.9  275  47 24   3.4   1.9
 34000 -43.6 -46.5  265  54 28   8.4   4.6 | -43.6 -46.5  270  47 24   8.2   4.5
 32000 -38.5 -37.3  270  50 26   8.4   4.6 | -38.7 -37.7  270  47 24   8.2   4.5
 30000 -32.6 -26.7  270  44 22   9.0   4.9 | -32.8 -27.0  270  45 23   9.0   4.9
 29000 -29.9 -21.8  265  41 21   9.0   4.9 | -30.1 -22.2  275  44 23   9.0   4.9
 28000 -27.2 -17.0  265  37 19   7.8   4.3 | -27.4 -17.3  275  43 22   8.2   4.5
 27000 -25.3 -13.5  265  35 18   6.1   3.3 | -25.4 -13.7  275  41 21   6.7   3.7
 26000 -23.5 -10.3  265  32 17   6.1   3.3 | -23.3  -9.9  275  38 20   6.7   3.7
 25000 -21.6  -6.9  265  29 15   6.1   3.4 | -21.3  -6.3  275  36 18   6.9   3.8
 24000 -19.9  -3.8  270  28 14   5.7   3.1 | -19.7  -3.5  280  34 17   5.1   2.8
 23000 -18.2  -0.8  280  27 14   5.7   3.1 | -18.1  -0.6  280  32 17   5.1   2.8
 22000 -16.5   2.3  285  27 14   5.7   3.1 | -16.6   2.1  285  31 16   5.0   2.8
 21000 -14.5   5.9  285  28 14   6.7   3.7 | -14.7   5.5  285  32 16   6.6   3.6
 20000 -12.5   9.5  290  29 15   6.7   3.7 | -12.8   9.0  280  34 17   6.7   3.7
 19500 -11.6  11.1  290  29 15   6.7   3.7 | -11.8  10.8  280  35 18   6.7   3.7
 19000 -10.5  13.1  290  30 15   7.2   3.9 | -10.8  12.6  280  35 18   8.0   4.4
 18500  -9.5  14.9  290  30 15   7.3   4.0 |  -9.6  14.7  280  34 17   8.4   4.6
 18000  -8.4  16.9  290  30 16   7.4   4.0 |  -8.4  16.9  280  33 17   8.6   4.7
 17500  -7.3  18.9  290  29 15   7.4   4.1 |  -7.2  19.0  280  31 16   8.7   4.8
 17000  -6.3  20.7  290  28 14   7.5   4.1 |  -5.9  21.4  280  28 14   8.7   4.8
 16500  -5.2  22.6  290  26 13   8.1   4.4 |  -4.6  23.7  280  25 13   9.1   5.0
 16000  -4.0  24.8  285  23 12   8.2   4.5 |  -3.3  26.1  280  23 12   9.1   5.0
 15500  -2.8  27.0  285  19 10   8.8   4.8 |  -1.9  28.6  280  22 11   8.9   4.9
 15000  -0.8  30.6  285  16  8   9.4   5.1 |   0.0  32.0  285  18  9   8.7   4.8
 14500   0.6  33.1  290  14  7   9.1   5.0 |   1.3  34.3  285  15  8   8.0   4.4
 14000   1.9  35.4  290  12  6   9.0   4.9 |   2.4  36.3  285  12  6   7.8   4.3
 13500   3.3  37.9  295  10  5   9.1   5.0 |   3.5  38.3  285   9  4   7.9   4.3
 13000   4.6  40.3  300   8  4   9.1   5.0 |   4.7  40.5  285   6  3   7.9   4.3
 12500   6.0  42.8  305   6  3   9.3   5.1 |   5.9  42.6  280   3  2   7.9   4.3
 12000   7.4  45.3  310   5  2   9.2   5.1 |   7.0  44.6  270   2  1   7.6   4.2
 11750   8.0  46.4  315   4  2   9.4   5.2 |   7.6  45.7  235   1  0   7.7   4.2
 11500   8.7  47.7  320   4  2   8.8   4.8 |   8.1  46.6  175   1  1   7.4   4.1
 11250   9.4  48.9  325   3  2   8.8   4.8 |   8.6  47.5  160   2  1   7.0   3.8
 11000  10.1  50.2  330   3  1   9.5   5.2 |   9.1  48.4  155   3  1   7.1   3.9
 10750  10.8  51.4  340   2  1   9.6   5.3 |   9.7  49.5  150   4  2   7.3   4.0
 10500  11.5  52.7  350   2  1   9.1   5.0 |  10.2  50.4  145   5  2   6.9   3.8
 10250  12.1  53.8  005   1  1   7.7   4.2 |  10.6  51.1  150   5  3   5.3   2.9
 10000  12.6  54.7  035   1  0   9.1   5.0 |  11.0  51.8  150   6  3   6.7   3.7
  9750  13.4  56.1  065   1  0  10.8   5.9 |  11.6  52.9  150   7  4   8.7   4.8
  9500  14.2  57.6  085   1  1   9.9   5.5 |  12.2  54.0  155   8  4   8.1   4.4
  9250  14.9  58.8  095   1  1   9.3   5.1 |  12.7  54.9  155   9  5   7.7   4.2
  9000  15.6  60.1  105   2  1   9.5   5.2 |  13.3  55.9  155   9  5   8.0   4.4
  8750  16.3  61.3  110   2  1  10.9   6.0 |  14.0  57.2  155  10  5  10.4   5.7
  8500  17.2  63.0  110   2  1  10.9   6.0 |  14.8  58.6  155  10  5  10.7   5.9
  8250  17.9  64.2  110   2  1  10.2   5.6 |  15.5  59.9  155  10  5   9.5   5.2
  8000  18.7  65.7  115   2  1  10.2   5.6 |  16.2  61.2  155  10  5   9.4   5.2
  7750  19.5  67.1  115   2  1  10.6   5.8 |  16.9  62.4  155  10  5  10.3   5.7
  7500  20.3  68.5  115   3  1  11.4   6.2 |  17.7  63.9  155  10  5   8.5   4.6
  7250  21.1  70.0  110   3  1  11.6   6.4 |  18.1  64.6  155   9  5   5.5   3.0
  7000  21.9  71.4  110   3  1  11.5   6.3 |  18.6  65.5  155   9  5   7.8   4.3
  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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