Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 161133
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0533 MDT Wednesday, July 16, 2014

This forecast is for Wednesday, July 16, 2014:

If the trigger temperature of 74.0 F/23.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 44 ft/min (0.2 m/s)
   Maximum height of thermals.................. 7994 ft MSL (1236 ft AGL)

Forecast maximum temperature................... 71.0 F/22.1 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7245 ft MSL (487 ft AGL)
Thermal soaring outlook for Thursday 07/17..... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Poor
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 40463 ft MSL (33705 ft AGL)
Wave soaring outlook for Thursday 07/17........ Poor

Remarks...

Sunrise/Sunset.................... 05:46:43 / 20:23:34 MDT
Total possible sunshine........... 14 hr 36 min 51 sec (876 min 51 sec)
Altitude of sun at 13:05:04 MDT... 72.30 degrees

Upper air data from numerical model forecast valid on 07/16/2014 at 0600 MDT

Freezing level.................. 15568 ft MSL (8810 ft AGL)
Convective condensation level... 15540 ft MSL (8782 ft AGL)
Lifted condensation level....... 13809 ft MSL (7051 ft AGL)
Lifted index.................... -0.9
K index......................... +27.2

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   315   38   19   2.4   1.3      M     M       M      M    M
 45000  -60.5 -76.9   310   64   33   3.8   2.1      M     M       M      M    M
 40000  -54.2 -65.6   305   87   45   7.9   4.3      M     M       M      M    M
 38000  -49.4 -56.9   305   81   42   7.9   4.4      M     M       M      M    M
 36000  -44.7 -48.5   300   75   39   7.9   4.4      M     M       M      M    M
 34000  -40.1 -40.2   300   68   35   7.6   4.2      M     M       M      M    M
 32000  -35.5 -31.9   300   60   31   7.6   4.2      M     M       M      M    M
 30000  -30.8 -23.4   305   50   26   6.8   3.7   38.8 101.8    13.3      M    M
 29000  -28.7 -19.7   305   46   23   6.8   3.7   37.7  99.9    12.6      M    M
 28000  -26.7 -16.1   305   41   21   7.0   3.8   36.7  98.1    12.0      M    M
 27000  -24.6 -12.3   305   39   20   7.1   3.9   35.6  96.1    11.2      M    M
 26000  -22.5  -8.5   310   37   19   7.1   3.9   34.6  94.3    10.6      M    M
 25000  -20.3  -4.5   310   35   18   7.1   3.9   33.7  92.7    10.0      M    M
 24000  -18.3  -0.9   310   34   18   6.9   3.8   32.7  90.8     9.2      M    M
 23000  -16.2   2.8   310   34   17   6.9   3.8   31.6  88.9     8.4      M    M
 22000  -14.2   6.4   310   33   17   6.9   3.8   30.7  87.2     7.7      M    M
 21000  -12.1  10.2   310   33   17   6.9   3.8   29.6  85.3     6.8      M    M
 20000  -10.1  13.8   310   33   17   7.0   3.9   28.7  83.6     6.0      M    M
 19500   -9.1  15.6   310   33   17   7.0   3.8   28.2  82.8     5.6      M    M
 19000   -8.0  17.6   310   33   17   8.4   4.6   27.9  82.2     5.2      M    M
 18500   -6.8  19.8   310   32   16   8.7   4.8   27.7  81.8     5.0      M    M
 18000   -5.6  21.9   310   30   15   8.7   4.8   27.5  81.6     4.8      M    M
 17500   -4.5  23.9   310   28   15   7.7   4.2   27.2  81.0     4.5      M    M
 17000   -3.4  25.9   310   27   14   7.8   4.3   26.9  80.4     4.1      M    M
 16500   -2.3  27.9   310   25   13   7.6   4.2   26.6  79.8     3.8      M    M
 16000   -1.2  29.8   310   23   12   7.6   4.2   26.2  79.1     3.4      M    M
 15500   -0.1  31.8   310   21   11   7.9   4.4   25.9  78.5     3.1      M    M
 15000    1.1  34.0   315   20   10   8.3   4.6   25.6  78.1     2.8      M    M
 14500    2.9  37.2   315   18   10   8.8   4.8   25.3  77.5     2.5      M    M
 14000    4.3  39.7   320   19   10   9.0   4.9   25.2  77.3     2.4      M    M
 13500    5.6  42.1   320   19   10   9.3   5.1   25.1  77.1     2.3      M    M
 13000    7.0  44.6   325   19   10   9.5   5.2   25.0  77.0     2.2      M    M
 12500    8.4  47.1   325   20   10   7.9   4.3   25.0  77.0     2.2      M    M
 12000    9.6  49.3   330   21   11   9.4   5.2   24.7  76.5     1.9      M    M
 11750   10.2  50.4   330   21   11   9.3   5.1   24.7  76.4     1.8      M    M
 11500   10.9  51.6   330   22   11   8.3   4.5   24.6  76.3     1.8      M    M
 11250   11.5  52.7   330   22   11   8.5   4.6   24.5  76.1     1.7      M    M
 11000   12.2  54.0   330   22   11   9.7   5.3   24.4  76.0     1.6      M    M
 10750   12.9  55.2   330   22   11   9.4   5.2   24.4  76.0     1.6      M    M
 10500   13.6  56.5   330   22   11   9.3   5.1   24.4  75.9     1.6      M    M
 10250   14.2  57.6   330   22   11   7.5   4.1   24.3  75.8     1.5      M    M
 10000   14.8  58.6   325   22   11   8.8   4.8   24.1  75.5     1.3      M    M
  9750   15.5  59.9   325   21   11  10.9   6.0   24.2  75.6     1.3      M    M
  9500   16.3  61.3   325   21   11  10.1   5.5   24.2  75.6     1.4      M    M
  9250   17.0  62.6   325   20   11   9.0   4.9   24.2  75.6     1.4      M    M
  9000   17.6  63.7   320   20   10   8.4   4.6   24.2  75.5     1.3      M    M
  8750   18.3  64.9   315   20   10  10.3   5.6   24.1  75.4     1.2      M    M
  8500   19.0  66.2   315   20   10   7.9   4.4   24.1  75.4     1.2      M    M
  8250   19.3  66.7   310   19   10   1.9   1.0   23.7  74.7     0.8      M    M
  8000   19.2  66.6   305   18    9  -3.4  -1.9   23.0  73.3    -0.0     44  0.2
  7750   19.1  66.4   300   17    9   7.9   4.3   22.2  71.9    -0.8     39  0.2
  7500   19.8  67.6   295   15    8  -2.3  -1.3   22.1  71.8    -0.9     13  0.1
  7250   18.2  64.8   290   13    7 -31.5 -17.3   20.2  68.4    -2.9     54  0.3
  7000   15.7  60.3   290   10    5 -25.3 -13.9   17.6  63.7    -5.6    119  0.6
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           07/16/2014 at 0900 MDT          |       07/16/2014 at 1200 MDT
                                           |
K index... +23.5  LI... -3.5               | K index... +32.4  LI... -3.7
CAPE... +903.7  CIN... -14.3               | CAPE... +1307.0  CIN... -12.5
                                           |
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 -64.7 -84.5  315  37 19   2.2   1.2 | -63.2 -81.8  315  35 18   2.5   1.4
 45000 -60.7 -77.3  305  60 31   4.0   2.2 | -59.1 -74.4  310  54 28   2.9   1.6
 40000 -54.1 -65.4  305  80 41   7.0   3.8 | -54.3 -65.7  305  63 32   6.2   3.4
 38000 -49.8 -57.6  305  75 39   7.0   3.9 | -50.6 -59.1  310  58 30   6.1   3.4
 36000 -45.6 -50.1  305  71 36   7.0   3.8 | -46.9 -52.4  310  53 27   6.1   3.3
 34000 -41.2 -42.2  305  63 33   7.5   4.1 | -42.2 -44.0  310  50 26   8.4   4.6
 32000 -36.7 -34.1  310  55 28   7.5   4.1 | -37.2 -35.0  310  47 24   8.4   4.6
 30000 -32.2 -26.0  310  48 25   7.5   4.1 | -31.8 -25.2  310  44 23   7.9   4.4
 29000 -29.4 -20.9  310  44 23   7.5   4.1 | -29.4 -20.9  310  43 22   7.9   4.4
 28000 -27.2 -17.0  310  41 21   7.6   4.2 | -27.0 -16.6  310  41 21   7.6   4.2
 27000 -24.9 -12.8  310  38 20   7.6   4.2 | -24.8 -12.6  310  40 20   7.5   4.1
 26000 -22.6  -8.7  305  35 18   7.6   4.2 | -22.5  -8.5  305  38 20   7.5   4.1
 25000 -20.3  -4.5  305  33 17   7.6   4.2 | -20.3  -4.5  305  36 19   7.5   4.1
 24000 -18.1  -0.6  305  31 16   7.2   3.9 | -18.2  -0.8  305  35 18   6.9   3.8
 23000 -16.0   3.2  305  30 16   7.2   3.9 | -16.1   3.0  305  34 18   6.9   3.8
 22000 -13.8   7.2  305  29 15   7.1   3.9 | -14.0   6.8  305  33 17   7.1   3.9
 21000 -11.8  10.8  310  28 15   6.8   3.8 | -11.7  10.9  305  33 17   7.7   4.2
 20000  -9.8  14.4  315  28 14   6.9   3.8 |  -9.5  14.9  305  34 17   7.8   4.3
 19500  -8.8  16.2  315  27 14   7.1   3.9 |  -8.3  17.1  310  34 17   8.0   4.4
 19000  -7.8  18.0  315  27 14   5.1   2.8 |  -7.3  18.9  310  34 18   5.3   2.9
 18500  -7.1  19.2  315  28 15   5.1   2.8 |  -6.6  20.1  305  35 18   5.5   3.0
 18000  -6.4  20.5  320  29 15   5.8   3.2 |  -5.9  21.4  305  37 19   6.2   3.4
 17500  -5.4  22.3  315  28 15   7.6   4.2 |  -5.0  23.0  305  36 18   7.4   4.1
 17000  -4.4  24.1  315  28 14   7.5   4.1 |  -4.0  24.8  300  34 18   7.5   4.1
 16500  -3.2  26.2  310  27 14   8.9   4.9 |  -2.9  26.8  300  33 17   8.5   4.7
 16000  -2.0  28.4  310  27 14   9.0   4.9 |  -1.7  28.9  295  31 16   8.5   4.7
 15500  -0.7  30.7  310  27 14   9.2   5.0 |  -0.5  31.1  295  30 15   8.6   4.7
 15000   0.6  33.1  310  27 14   9.3   5.1 |   0.7  33.3  295  28 14   8.6   4.7
 14500   2.6  36.7  310  26 13   9.3   5.1 |   2.5  36.5  290  25 13   9.0   4.9
 14000   3.9  39.0  310  25 13   9.3   5.1 |   3.9  39.0  290  23 12   9.1   5.0
 13500   5.3  41.5  305  24 12   9.1   5.0 |   5.2  41.4  290  21 11   9.2   5.1
 13000   6.6  43.9  310  25 13   8.9   4.9 |   6.6  43.9  290  19 10   9.3   5.1
 12500   7.9  46.2  315  25 13   7.9   4.3 |   7.9  46.2  290  17  9   8.0   4.4
 12000   9.1  48.4  315  25 13   9.2   5.1 |   9.1  48.4  290  16  8   9.2   5.0
 11750   9.7  49.5  315  25 13   8.9   4.9 |   9.8  49.6  290  15  8   8.9   4.9
 11500  10.4  50.7  315  25 13   9.2   5.1 |  10.4  50.7  290  14  7   8.5   4.7
 11250  11.1  52.0  315  25 13   9.4   5.1 |  11.0  51.8  290  13  7   8.2   4.5
 11000  11.8  53.2  315  25 13   9.2   5.1 |  11.6  52.9  290  12  6   8.5   4.7
 10750  12.5  54.5  320  24 12   9.4   5.1 |  12.3  54.1  295  11  6   8.5   4.7
 10500  13.2  55.8  320  24 12   9.0   5.0 |  12.9  55.2  295  10  5   8.1   4.4
 10250  13.8  56.8  320  23 12   8.1   4.5 |  13.4  56.1  300   8  4   6.3   3.5
 10000  14.4  57.9  320  23 12   8.8   4.9 |  13.8  56.8  315   7  4   7.6   4.2
  9750  15.1  59.2  320  22 11   9.8   5.4 |  14.4  57.9  330   6  3   9.3   5.1
  9500  15.8  60.4  320  21 11   9.2   5.1 |  15.1  59.2  350   6  3   8.8   4.9
  9250  16.4  61.5  320  20 10   8.3   4.6 |  15.7  60.3  360   7  3   8.8   4.8
  9000  17.0  62.6  320  19 10   8.4   4.6 |  16.3  61.3  005   7  4   9.1   5.0
  8750  17.6  63.7  325  18  9  10.0   5.5 |  17.1  62.8  010   7  4  10.5   5.8
  8500  18.3  64.9  325  18  9  10.0   5.5 |  17.9  64.2  010   8  4  10.9   6.0
  8250  19.0  66.2  325  16  8   9.0   4.9 |  18.6  65.5  015   8  4  10.3   5.6
  8000  19.6  67.3  320  15  8   8.7   4.8 |  19.4  66.9  015   8  4  10.6   5.8
  7750  20.2  68.4  320  13  7   9.6   5.2 |  20.2  68.4  015   8  4   9.4   5.2
  7500  20.9  69.6  320  12  6   9.3   5.1 |  20.8  69.4  015   8  4  11.3   6.2
  7250  21.5  70.7  320  11  6   8.1   4.4 |  21.8  71.2  015   8  4  14.9   8.2
  7000  22.1  71.8  320  10  5   9.0   4.9 |  22.9  73.2  015   8  4  12.9   7.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/16/2014 at 1500 MDT          |       07/16/2014 at 1800 MDT
                                           |
K index... +32.1  LI... -3.7               | K index... +27.7  LI... -3.3
CAPE... +873.5  CIN... -5.1                | CAPE... +741.3  CIN... -6.3
                                           |
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 -64.0 -83.2  305  36 18   1.4   0.8 | -64.2 -83.6  310  37 19   1.2   0.7
 45000 -60.6 -77.1  305  51 26   3.9   2.1 | -61.1 -78.0  305  51 26   3.8   2.1
 40000 -54.3 -65.7  300  49 25   7.0   3.8 | -54.8 -66.6  295  44 23   7.6   4.2
 38000 -50.1 -58.2  300  44 23   7.0   3.9 | -50.2 -58.4  295  40 21   7.7   4.2
 36000 -45.9 -50.6  300  40 21   6.9   3.8 | -45.6 -50.1  290  36 18   7.7   4.2
 34000 -40.8 -41.4  305  40 20   8.7   4.8 | -40.7 -41.3  290  36 19   8.2   4.5
 32000 -35.6 -32.1  305  41 21   8.7   4.8 | -35.8 -32.4  295  38 20   8.3   4.5
 30000 -30.1 -22.2  305  41 21   8.1   4.5 | -30.3 -22.5  295  39 20   8.1   4.4
 29000 -27.7 -17.9  305  41 21   8.2   4.5 | -27.9 -18.2  300  40 20   8.1   4.4
 28000 -25.3 -13.5  305  41 21   7.5   4.1 | -25.5 -13.9  300  40 21   7.6   4.2
 27000 -23.1  -9.6  305  42 22   7.2   4.0 | -23.3  -9.9  300  40 20   7.3   4.0
 26000 -21.0  -5.8  305  43 22   7.3   4.0 | -21.2  -6.2  305  40 20   7.3   4.0
 25000 -18.8  -1.8  305  44 23   7.3   4.0 | -19.0  -2.2  305  40 20   7.4   4.0
 24000 -16.9   1.6  305  44 23   6.4   3.5 | -17.0   1.4  305  40 20   6.5   3.6
 23000 -15.0   5.0  305  44 23   6.4   3.5 | -15.1   4.8  305  40 20   6.6   3.6
 22000 -13.2   8.2  300  44 22   6.5   3.5 | -13.2   8.2  305  40 20   6.6   3.6
 21000 -11.3  11.7  295  42 22   6.5   3.6 | -11.3  11.7  300  38 20   6.5   3.6
 20000  -9.4  15.1  290  40 21   6.6   3.6 |  -9.4  15.1  300  37 19   6.6   3.6
 19500  -8.5  16.7  285  40 20   6.6   3.6 |  -8.4  16.9  295  36 19   6.6   3.6
 19000  -7.5  18.5  285  39 20   7.1   3.9 |  -7.5  18.5  295  35 18   6.7   3.7
 18500  -6.5  20.3  280  37 19   7.2   4.0 |  -6.5  20.3  290  35 18   6.7   3.7
 18000  -5.4  22.3  280  36 19   7.2   3.9 |  -5.6  21.9  285  34 18   6.7   3.7
 17500  -4.4  24.1  280  34 17   6.6   3.6 |  -4.6  23.7  285  33 17   6.9   3.8
 17000  -3.5  25.7  275  31 16   6.7   3.7 |  -3.6  25.5  280  32 16   6.9   3.8
 16500  -2.6  27.3  275  28 14   6.4   3.5 |  -2.6  27.3  280  30 16   7.4   4.1
 16000  -1.6  29.1  275  25 13   6.4   3.5 |  -1.5  29.3  280  28 15   7.5   4.1
 15500  -0.7  30.7  275  23 12   6.9   3.8 |  -0.4  31.3  280  26 14   7.7   4.2
 15000   0.9  33.6  270  19 10   7.7   4.2 |   0.8  33.4  275  25 13   8.0   4.4
 14500   2.0  35.6  270  16  8   7.4   4.1 |   2.5  36.5  275  23 12   7.4   4.1
 14000   3.1  37.6  265  12  6   7.3   4.0 |   3.5  38.3  265  20 10   7.1   3.9
 13500   4.1  39.4  255   9  5   7.6   4.2 |   4.5  40.1  260  18  9   6.6   3.6
 13000   5.2  41.4  250   5  3   8.1   4.5 |   5.3  41.5  250  15  7   5.7   3.1
 12500   6.4  43.5  245   1  1   7.1   3.9 |   6.1  43.0  235  11  6   4.1   2.3
 12000   7.5  45.5  000   0  0   9.5   5.2 |   6.7  44.1  220   7  4   6.1   3.3
 11750   8.2  46.8  075   1  1   8.6   4.7 |   7.1  44.8  205   5  3   5.2   2.8
 11500   8.8  47.8  070   2  1  10.2   5.6 |   7.5  45.5  180   3  2   6.8   3.7
 11250   9.6  49.3  065   2  1  10.0   5.5 |   8.0  46.4  145   3  1   8.6   4.7
 11000  10.3  50.5  065   3  1   8.4   4.6 |   8.7  47.7  105   3  2   8.1   4.5
 10750  10.9  51.6  060   3  2   8.7   4.8 |   9.2  48.6  080   4  2   7.7   4.2
 10500  11.5  52.7  060   4  2   8.7   4.7 |   9.8  49.6  070   6  3   7.9   4.3
 10250  12.1  53.8  060   4  2   9.0   4.9 |  10.3  50.5  065   7  4   8.1   4.5
 10000  12.8  55.0  060   5  2   9.7   5.3 |  10.9  51.6  060   8  4   8.9   4.9
  9750  13.6  56.5  060   5  3  10.1   5.6 |  11.6  52.9  055   9  5   9.4   5.2
  9500  14.3  57.7  060   6  3   9.9   5.4 |  12.3  54.1  055   9  5   9.1   5.0
  9250  15.0  59.0  055   6  3   9.2   5.0 |  12.9  55.2  050  10  5   8.0   4.4
  9000  15.7  60.3  055   6  3   9.2   5.0 |  13.4  56.1  050  11  6   7.9   4.3
  8750  16.4  61.5  055   7  3  10.3   5.7 |  14.0  57.2  045  12  6   9.5   5.2
  8500  17.2  63.0  055   7  4  10.6   5.8 |  14.8  58.6  045  12  6   9.9   5.4
  8250  17.9  64.2  055   7  4   9.9   5.5 |  15.4  59.7  045  12  6   9.2   5.1
  8000  18.7  65.7  055   7  4  10.1   5.5 |  16.1  61.0  045  12  6   8.9   4.9
  7750  19.4  66.9  055   7  4   9.3   5.1 |  16.8  62.2  040  12  6  10.0   5.5
  7500  20.0  68.0  050   7  4   7.5   4.1 |  17.5  63.5  040  12  6   8.3   4.6
  7250  20.5  68.9  050   7  4   6.7   3.7 |  17.9  64.2  040  12  6   5.1   2.8
  7000  20.9  69.6  050   7  4   6.8   3.7 |  18.3  64.9  040  11  6   6.8   3.7
  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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