Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 171020
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0420 MDT Friday, October 17, 2014

This forecast is for Friday, October 17, 2014:

If the trigger temperature of 62.2 F/16.8 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 308 ft/min (1.6 m/s)
   Maximum height of thermals.................. 10465 ft MSL (3707 ft AGL)

Forecast maximum temperature................... 61.0 F/16.6 C
Time of trigger temperature.................... 1415 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9578 ft MSL (2820 ft AGL)
Thermal soaring outlook for Saturday 10/18..... Excellent

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....................... 45689 ft MSL (38931 ft AGL)
Wave soaring outlook for Saturday 10/18........ Poor

Remarks...

Sunrise/Sunset.................... 07:10:36 / 18:19:01 MDT
Total possible sunshine........... 11 hr 8 min 25 sec (668 min 25 sec)
Altitude of sun at 12:44:23 MDT... 41.64 degrees

Upper air data from numerical model forecast valid on 10/17/2014 at 0600 MDT

Freezing level.................. 13766 ft MSL (7008 ft AGL)
Convective condensation level... 17999 ft MSL (11241 ft AGL)
Lifted condensation level....... 14247 ft MSL (7489 ft AGL)
Lifted index.................... +5.0
K index......................... +9.6

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  -66.9 -88.4   280   59   31   0.2   0.1      M     M       M      M    M
 45000  -65.4 -85.7   280   76   39   4.9   2.7      M     M       M      M    M
 40000  -58.1 -72.6   280   76   39   5.8   3.2      M     M       M      M    M
 38000  -53.8 -64.8   280   71   37   7.2   4.0      M     M       M      M    M
 36000  -49.4 -56.9   280   66   34   7.2   4.0      M     M       M      M    M
 34000  -44.9 -48.8   280   64   33   7.8   4.3      M     M       M      M    M
 32000  -39.6 -39.3   285   62   32   7.9   4.3      M     M       M      M    M
 30000  -34.9 -30.8   285   60   31   7.8   4.3   35.0  95.1    14.6      M    M
 29000  -32.5 -26.5   285   58   30   7.8   4.3   34.3  93.8    14.2      M    M
 28000  -30.2 -22.4   285   57   29   7.9   4.3   33.7  92.7    13.9      M    M
 27000  -27.9 -18.2   285   55   28   7.6   4.2   32.9  91.2    13.4      M    M
 26000  -25.6 -14.1   290   53   27   7.6   4.2   32.0  89.7    12.8      M    M
 25000  -23.3  -9.9   290   51   26   7.6   4.2   31.3  88.4    12.4      M    M
 24000  -21.1  -6.0   290   47   24   7.5   4.1   30.5  87.0    11.8      M    M
 23000  -18.9  -2.0   290   43   22   7.5   4.1   29.7  85.4    11.2      M    M
 22000  -16.6   2.1   290   40   20   7.5   4.1   28.9  84.1    10.7      M    M
 21000  -14.4   6.1   285   37   19   7.4   4.1   28.1  82.6    10.1      M    M
 20000  -12.2  10.0   285   36   18   7.4   4.1   27.3  81.1     9.5      M    M
 19500  -11.1  12.0   285   35   18   7.4   4.0   26.9  80.4     9.2      M    M
 19000  -10.0  14.0   285   34   18   7.2   3.9   26.5  79.7     9.0      M    M
 18500   -9.0  15.8   285   33   17   6.7   3.7   26.0  78.8     8.5      M    M
 18000   -8.0  17.6   285   32   16   6.8   3.7   25.5  77.9     8.1      M    M
 17500   -7.0  19.4   285   31   16   6.9   3.8   25.0  77.0     7.7      M    M
 17000   -6.0  21.2   285   29   15   6.9   3.8   24.5  76.2     7.3      M    M
 16500   -5.0  23.0   285   28   15   6.4   3.5   24.1  75.3     6.9      M    M
 16000   -4.1  24.6   290   27   14   5.7   3.1   23.4  74.1     6.3      M    M
 15500   -2.8  27.0   290   25   13   5.3   2.9   22.4  72.3     5.5      M    M
 15000   -2.0  28.4   295   24   13   5.1   2.8   21.6  70.9     4.8      M    M
 14500   -1.3  29.7   295   24   12   5.7   3.1   20.9  69.5     4.1      M    M
 14000   -0.3  31.5   295   23   12   7.3   4.0   20.4  68.7     3.7      M    M
 13500    0.7  33.3   300   22   11   7.4   4.1   20.0  68.0     3.2      M    M
 13000    1.9  35.4   300   20   10   8.9   4.9   19.7  67.5     3.0      M    M
 12500    3.2  37.8   300   18    9   9.9   5.4   19.6  67.2     2.8      M    M
 12000    4.5  40.1   295   17    9   6.7   3.7   19.4  66.9     2.6      M    M
 11750    5.0  41.0   295   16    8   6.9   3.8   19.2  66.5     2.4      M    M
 11500    5.5  41.9   290   15    8   8.3   4.6   19.0  66.2     2.2      M    M
 11250    6.0  42.8   285   14    7   1.7   0.9   18.8  65.8     2.0      M    M
 11000    5.8  42.4   275   13    6  -0.9  -0.5   17.8  64.1     1.1      M    M
 10750    6.0  42.8   270   12    6   3.5   1.9   17.3  63.1     0.5      M    M
 10500    6.2  43.2   260   11    6   2.9   1.6   16.7  62.1    -0.0    307  1.6
 10250    6.3  43.3   250   11    6   0.0   0.0   16.2  61.1    -0.6    295  1.5
 10000    6.1  43.0   235   11    6  -3.0  -1.6   15.2  59.4    -1.5    294  1.5
  9750    5.9  42.6   225   12    6  -2.1  -1.1   14.3  57.7    -2.5    293  1.5
  9500    5.7  42.3   215   13    7  -2.2  -1.2   13.4  56.0    -3.4    291  1.5
  9250    5.6  42.1   205   14    7  -1.0  -0.6   12.5  54.5    -4.3    289  1.5
  9000    5.5  41.9   200   14    7   0.3   0.2   11.7  53.1    -5.1    282  1.4
  8750    5.5  41.9   195   14    7  -2.9  -1.6   10.9  51.6    -5.9    276  1.4
  8500    5.2  41.4   185   16    8  -2.8  -1.5    9.9  49.8    -7.0    278  1.4
  8250    5.2  41.4   185   16    8   3.4   1.8    9.2  48.5    -7.7    270  1.4
  8000    5.5  41.9   180   15    8   3.7   2.0    8.7  47.7    -8.1    253  1.3
  7750    5.9  42.6   180   14    7   7.7   4.2    8.3  47.0    -8.5    235  1.2
  7500    6.4  43.5   175   14    7   0.8   0.4    8.2  46.7    -8.7    212  1.1
  7250    5.8  42.4   180   11    6 -11.4  -6.2    7.3  45.1    -9.6    222  1.1
  7000    5.2  41.4   190    8    4  -2.7  -1.5    6.3  43.4   -10.6    233  1.2
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           10/17/2014 at 0900 MDT          |       10/17/2014 at 1200 MDT
                                           |
K index... +10.0  LI... +4.6               | K index... +9.9  LI... +4.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -66.7 -88.1  280  57 29   0.2   0.1 | -66.8 -88.2  280  54 28   0.3   0.2
 45000 -65.4 -85.7  275  76 39   4.6   2.5 | -65.3 -85.5  275  72 37   4.3   2.4
 40000 -58.5 -73.3  275  69 36   5.8   3.2 | -58.9 -74.0  275  60 31   5.6   3.1
 38000 -54.1 -65.4  280  65 33   7.4   4.1 | -54.4 -65.9  275  59 31   7.4   4.0
 36000 -49.6 -57.3  280  61 31   7.4   4.1 | -50.0 -58.0  275  59 30   7.4   4.0
 34000 -45.0 -49.0  285  59 30   7.8   4.3 | -44.7 -48.5  275  57 29   8.2   4.5
 32000 -39.8 -39.6  285  57 29   7.8   4.3 | -39.7 -39.5  280  54 28   8.2   4.5
 30000 -35.0 -31.0  290  55 28   8.0   4.4 | -34.9 -30.8  285  52 27   7.9   4.3
 29000 -32.6 -26.7  290  54 28   8.0   4.4 | -32.6 -26.7  285  51 26   7.9   4.3
 28000 -30.2 -22.4  290  53 27   8.0   4.4 | -30.2 -22.4  285  50 26   7.9   4.3
 27000 -27.9 -18.2  290  50 26   7.7   4.2 | -27.9 -18.2  285  47 24   7.8   4.3
 26000 -25.6 -14.1  290  47 24   7.7   4.2 | -25.6 -14.1  285  44 23   7.8   4.3
 25000 -23.3  -9.9  290  44 23   7.7   4.2 | -23.3  -9.9  290  41 21   7.8   4.3
 24000 -21.0  -5.8  290  41 21   7.6   4.2 | -20.9  -5.6  285  39 20   8.0   4.4
 23000 -18.7  -1.7  285  38 20   7.6   4.2 | -18.5  -1.3  285  38 19   8.0   4.4
 22000 -16.4   2.5  280  36 18   7.7   4.2 | -16.1   3.0  280  36 19   8.1   4.4
 21000 -14.2   6.4  280  34 18   7.2   4.0 | -14.0   6.8  280  35 18   6.5   3.6
 20000 -12.1  10.2  280  34 17   7.2   4.0 | -12.1  10.2  280  34 17   6.6   3.6
 19500 -11.0  12.2  280  34 17   7.2   4.0 | -11.1  12.0  280  33 17   6.6   3.6
 19000 -10.0  14.0  280  33 17   7.1   3.9 | -10.2  13.6  285  33 17   7.0   3.8
 18500  -8.9  16.0  280  33 17   7.0   3.8 |  -9.1  15.6  285  32 16   7.4   4.1
 18000  -7.9  17.8  280  32 16   7.0   3.9 |  -8.0  17.6  285  30 16   7.5   4.1
 17500  -6.9  19.6  280  30 16   6.1   3.4 |  -6.9  19.6  285  29 15   6.5   3.6
 17000  -6.0  21.2  280  29 15   6.1   3.4 |  -5.9  21.4  285  27 14   6.5   3.6
 16500  -5.1  22.8  280  27 14   6.3   3.5 |  -4.9  23.2  285  26 13   6.5   3.6
 16000  -3.7  25.3  285  24 13   6.5   3.5 |  -3.5  25.7  285  23 12   6.4   3.5
 15500  -2.7  27.1  285  23 12   6.1   3.4 |  -2.5  27.5  285  21 11   6.4   3.5
 15000  -1.8  28.8  290  22 11   6.0   3.3 |  -1.6  29.1  285  20 10   6.4   3.5
 14500  -0.9  30.4  290  21 11   5.9   3.2 |  -0.6  30.9  285  18  9   6.3   3.4
 14000  -0.0  32.0  295  20 11   5.8   3.2 |   0.3  32.5  285  17  9   6.1   3.4
 13500   0.8  33.4  295  20 10   6.0   3.3 |   1.2  34.2  290  16  8   6.3   3.4
 13000   1.7  35.1  300  19 10   7.0   3.8 |   2.2  36.0  290  15  8   7.0   3.9
 12500   2.7  36.9  300  18  9   7.8   4.3 |   3.2  37.8  290  14  7   6.6   3.6
 12000   3.9  39.0  300  15  8   7.8   4.3 |   4.2  39.6  290  13  7   7.5   4.1
 11750   4.5  40.1  300  15  7   7.9   4.3 |   4.7  40.5  290  12  6   7.3   4.0
 11500   5.1  41.2  300  14  7   8.0   4.4 |   5.2  41.4  290  12  6   7.4   4.0
 11250   5.6  42.1  305  13  7   5.9   3.3 |   5.7  42.3  290  11  6   7.2   4.0
 11000   6.0  42.8  300  12  6   5.6   3.1 |   6.3  43.3  295  10  5   7.2   4.0
 10750   6.5  43.7  300  11  6   6.9   3.8 |   6.8  44.2  295   9  5   7.4   4.0
 10500   7.0  44.6  295  10  5   6.8   3.7 |   7.4  45.3  295   8  4   7.3   4.0
 10250   7.4  45.3  290   9  5   0.2   0.1 |   7.8  46.0  295   7  4   4.5   2.5
 10000   7.1  44.8  280   8  4  -3.4  -1.9 |   8.1  46.6  295   7  3   3.1   1.7
  9750   7.0  44.6  265   7  4   0.4   0.2 |   8.4  47.1  290   6  3   4.7   2.6
  9500   7.0  44.6  250   7  4   0.2   0.1 |   8.7  47.7  290   5  3   3.3   1.8
  9250   6.9  44.4  235   7  4  -2.3  -1.3 |   8.7  47.7  285   5  2  -2.9  -1.6
  9000   6.6  43.9  215   7  4  -3.4  -1.9 |   8.3  46.9  265   4  2  -6.1  -3.3
  8750   6.3  43.3  200   8  4  -4.3  -2.4 |   7.9  46.2  230   3  2  -1.9  -1.0
  8500   6.0  42.8  190  10  5  -3.3  -1.8 |   7.9  46.2  195   4  2   2.8   1.6
  8250   5.9  42.6  185  10  5   0.5   0.3 |   8.2  46.8  180   5  3   5.8   3.2
  8000   5.9  42.6  185  10  5   0.7   0.4 |   8.6  47.5  170   6  3   5.9   3.2
  7750   6.0  42.8  180  10  5   2.2   1.2 |   9.1  48.4  165   6  3   8.2   4.5
  7500   6.2  43.2  175  10  5   4.3   2.4 |   9.8  49.6  160   7  3  11.6   6.4
  7250   6.5  43.7  175   9  4   4.0   2.2 |  10.7  51.3  160   7  3  11.4   6.2
  7000   6.8  44.2  175   7  4   4.4   2.4 |  11.5  52.7  160   7  3  11.8   6.4
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           10/17/2014 at 1500 MDT          |       10/17/2014 at 1800 MDT
                                           |
K index... +12.2  LI... +3.0               | K index... +15.3  LI... +1.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.3
                                           |
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 -66.8 -88.2  280  51 26   0.6   0.3 | -66.7 -88.1  280  42 22   0.6   0.3
 45000 -65.1 -85.2  270  67 35   4.0   2.2 | -64.9 -84.8  275  61 32   4.1   2.3
 40000 -59.0 -74.2  270  61 31   5.5   3.0 | -58.7 -73.7  275  55 28   5.4   2.9
 38000 -54.5 -66.1  270  63 32   7.6   4.2 | -54.2 -65.6  270  55 28   7.5   4.1
 36000 -50.0 -58.0  275  64 33   7.6   4.2 | -49.7 -57.5  265  55 28   7.5   4.1
 34000 -44.4 -47.9  275  60 31   8.5   4.7 | -44.4 -47.9  270  50 26   8.1   4.4
 32000 -39.3 -38.7  275  53 27   8.5   4.7 | -39.6 -39.3  280  44 23   8.1   4.4
 30000 -34.5 -30.1  280  48 25   7.7   4.2 | -34.8 -30.6  285  40 20   7.9   4.3
 29000 -32.2 -26.0  280  46 24   7.7   4.3 | -32.4 -26.3  285  38 19   7.9   4.3
 28000 -29.9 -21.8  285  44 23   7.8   4.3 | -30.1 -22.2  285  36 18   7.9   4.3
 27000 -27.6 -17.7  285  42 22   7.8   4.3 | -27.7 -17.9  285  33 17   7.9   4.3
 26000 -25.2 -13.4  285  40 21   7.8   4.3 | -25.3 -13.5  285  31 16   7.9   4.3
 25000 -22.9  -9.2  285  38 20   7.8   4.3 | -23.0  -9.4  285  29 15   7.9   4.3
 24000 -20.5  -4.9  285  36 19   8.0   4.4 | -20.6  -5.1  280  28 14   7.9   4.3
 23000 -18.1  -0.6  280  34 18   8.1   4.4 | -18.3  -0.9  280  27 14   7.9   4.4
 22000 -15.7   3.7  275  33 17   8.2   4.5 | -15.9   3.4  280  27 14   8.1   4.4
 21000 -13.7   7.3  275  32 16   6.0   3.3 | -13.9   7.0  285  26 14   6.0   3.3
 20000 -12.0  10.4  280  31 16   6.0   3.3 | -12.2  10.0  290  27 14   6.0   3.3
 19500 -11.1  12.0  285  31 16   6.0   3.3 | -11.3  11.7  295  27 14   6.0   3.3
 19000 -10.2  13.6  285  31 16   6.4   3.5 | -10.4  13.3  295  27 14   6.1   3.4
 18500  -9.2  15.4  290  29 15   6.9   3.8 |  -9.5  14.9  295  25 13   6.3   3.5
 18000  -8.2  17.2  290  28 14   6.9   3.8 |  -8.5  16.7  300  23 12   6.3   3.4
 17500  -7.1  19.2  290  26 13   7.2   4.0 |  -7.6  18.3  300  22 11   6.9   3.8
 17000  -6.0  21.2  295  25 13   7.2   3.9 |  -6.6  20.1  300  21 11   6.9   3.8
 16500  -4.5  23.9  295  23 12   6.8   3.7 |  -5.1  22.8  295  19 10   6.4   3.5
 16000  -3.4  25.9  295  22 11   6.9   3.8 |  -4.1  24.6  295  18  9   6.5   3.6
 15500  -2.4  27.7  295  21 11   6.8   3.8 |  -3.2  26.2  290  17  9   7.1   3.9
 15000  -1.4  29.5  295  20 10   6.8   3.7 |  -2.2  28.0  280  15  8   7.4   4.1
 14500  -0.3  31.5  295  19 10   6.6   3.6 |  -1.1  30.0  270  13  7   8.0   4.4
 14000   0.6  33.1  290  17  9   6.3   3.5 |   0.2  32.4  265  11  6   8.9   4.9
 13500   1.5  34.7  290  15  8   6.4   3.5 |   1.5  34.7  260  10  5   8.7   4.8
 13000   2.4  36.3  290  13  7   6.7   3.7 |   2.7  36.9  255   8  4   7.3   4.0
 12500   3.4  38.1  285  10  5   7.3   4.0 |   3.8  38.8  245   6  3   6.8   3.7
 12000   4.5  40.1  285   9  4   7.5   4.1 |   4.7  40.5  225   5  3   6.3   3.4
 11750   5.0  41.0  280   8  4   7.6   4.2 |   5.2  41.4  215   5  3   6.2   3.4
 11500   5.6  42.1  280   7  4   7.7   4.2 |   5.6  42.1  205   5  3   6.2   3.4
 11250   6.1  43.0  280   6  3   7.2   4.0 |   6.1  43.0  190   5  3   6.4   3.5
 11000   6.6  43.9  275   5  3   6.7   3.7 |   6.6  43.9  185   5  3   6.1   3.4
 10750   7.1  44.8  275   4  2   6.6   3.6 |   7.1  44.8  180   6  3   5.8   3.2
 10500   7.6  45.7  270   3  2   6.6   3.6 |   7.5  45.5  175   6  3   6.0   3.3
 10250   8.1  46.6  265   2  1   6.0   3.3 |   7.9  46.2  170   7  3   3.8   2.1
 10000   8.5  47.3  245   2  1   3.7   2.1 |   8.1  46.6  170   7  4   2.1   1.2
  9750   8.6  47.5  220   2  1   2.1   1.2 |   8.3  46.9  175   7  4   2.6   1.5
  9500   8.7  47.7  185   2  1   2.1   1.2 |   8.4  47.1  175   8  4   2.4   1.3
  9250   8.8  47.8  165   2  1   1.5   0.8 |   8.5  47.3  170   8  4   1.4   0.7
  9000   8.9  48.0  160   4  2   1.4   0.7 |   8.6  47.5  170   8  4   0.8   0.5
  8750   9.1  48.4  160   5  2   6.5   3.6 |   8.6  47.5  170   8  4   1.5   0.8
  8500   9.8  49.6  155   5  3   9.9   5.5 |   8.7  47.7  170   9  4   3.7   2.1
  8250  10.4  50.7  150   6  3   8.7   4.8 |   9.1  48.4  165   9  5   7.4   4.0
  8000  11.1  52.0  150   6  3   9.0   4.9 |   9.7  49.5  165   9  5   7.9   4.3
  7750  11.7  53.1  155   6  3   8.7   4.8 |  10.3  50.5  165   9  5   9.5   5.2
  7500  12.4  54.3  150   6  3  10.0   5.5 |  11.0  51.8  165   9  5   6.5   3.6
  7250  13.2  55.8  150   6  3  11.6   6.4 |  11.2  52.2  165   8  4   1.3   0.7
  7000  14.0  57.2  150   6  3  10.7   5.9 |  11.4  52.5  160   7  3   4.9   2.7
  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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