Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 011032
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0432 MDT Monday, September 1, 2014

This forecast is for Monday, September 1, 2014:

If the trigger temperature of 65.8 F/18.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 804 ft/min (4.1 m/s)
   Maximum height of thermals.................. 15878 ft MSL (9120 ft AGL)

Forecast maximum temperature................... 74.0 F/23.8 C
Time of trigger temperature.................... 1045 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................. 11484 ft MSL (4726 ft AGL)
Thermal soaring outlook for Tuesday 09/02...... 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)................ Weak NVA
Potential height of wave....................... 40503 ft MSL (33745 ft AGL)
Wave soaring outlook for Tuesday 09/02......... Poor

Remarks...

Sunrise/Sunset.................... 06:27:52 / 19:30:42 MDT
Total possible sunshine........... 13 hr 2 min 50 sec (782 min 50 sec)
Altitude of sun at 12:58:51 MDT... 59.14 degrees

Upper air data from numerical model forecast valid on 09/01/2014 at 0600 MDT

Freezing level.................. 14426 ft MSL (7668 ft AGL)
Convective condensation level... 13548 ft MSL (6790 ft AGL)
Lifted condensation level....... 14008 ft MSL (7250 ft AGL)
Lifted index.................... -1.4
K index......................... +11.6

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  -63.1 -81.6   275   37   19   2.2   1.2      M     M       M      M    M
 45000  -59.6 -75.3   275   56   29   2.2   1.2      M     M       M      M    M
 40000  -55.9 -68.6   275   73   37   8.0   4.4      M     M       M      M    M
 38000  -51.6 -60.9   280   69   35   7.3   4.0      M     M       M      M    M
 36000  -47.2 -53.0   280   65   34   7.3   4.0      M     M       M      M    M
 34000  -42.3 -44.1   280   64   33   8.5   4.7      M     M       M      M    M
 32000  -36.5 -33.7   280   63   32   8.5   4.7      M     M       M      M    M
 30000  -31.4 -24.5   280   61   31   8.6   4.7   38.6 101.4    11.8      M    M
 29000  -28.8 -19.8   280   60   31   8.6   4.7   38.2 100.7    11.6      M    M
 28000  -26.2 -15.2   280   59   30   8.4   4.6   37.9 100.2    11.5      M    M
 27000  -23.8 -10.8   280   59   30   7.7   4.2   37.0  98.6    11.0      M    M
 26000  -21.5  -6.7   280   58   30   7.7   4.2   36.2  97.2    10.5      M    M
 25000  -19.2  -2.6   280   58   30   7.8   4.3   35.6  96.1    10.1      M    M
 24000  -17.0   1.4   280   57   29   7.4   4.0   34.7  94.5     9.5      M    M
 23000  -14.8   5.4   280   55   28   7.4   4.0   33.8  92.9     8.8      M    M
 22000  -12.6   9.3   280   54   28   7.5   4.1   33.1  91.5     8.2      M    M
 21000  -10.7  12.7   280   52   27   5.9   3.3   31.9  89.3     7.2      M    M
 20000   -8.9  16.0   280   50   26   5.9   3.2   30.5  86.9     6.2      M    M
 19500   -8.1  17.4   280   49   25   5.9   3.2   29.9  85.8     5.6      M    M
 19000   -7.2  19.0   280   49   25   5.1   2.8   29.3  84.7     5.1      M    M
 18500   -6.6  20.1   280   48   24   4.0   2.2   28.3  83.0     4.3      M    M
 18000   -6.0  21.2   280   47   24   4.0   2.2   27.4  81.2     3.4      M    M
 17500   -5.4  22.3   280   46   24   4.7   2.6   26.4  79.6     2.6      M    M
 17000   -4.7  23.5   280   45   23   4.7   2.6   25.6  78.1     1.8      M    M
 16500   -4.0  24.8   280   44   23   5.1   2.8   24.8  76.6     1.0      M    M
 16000   -3.3  26.1   280   43   22   5.6   3.1   24.0  75.3     0.3      M    M
 15500   -2.1  28.2   280   40   21   6.8   3.7   23.1  73.6    -0.7    764  3.9
 15000   -1.0  30.2   280   37   19   7.3   4.0   22.7  72.8    -1.1    718  3.6
 14500    0.1  32.2   280   33   17   7.8   4.3   22.3  72.1    -1.5    671  3.4
 14000    1.3  34.3   280   30   15   8.8   4.8   22.1  71.8    -1.7    619  3.1
 13500    2.6  36.7   275   26   13   8.9   4.9   22.0  71.5    -1.9    567  2.9
 13000    3.9  39.0   270   23   12   9.3   5.1   21.9  71.3    -2.1    513  2.6
 12500    5.2  41.4   260   21   11   9.2   5.0   21.8  71.2    -2.2    458  2.3
 12000    6.3  43.3   260   20   10   7.1   3.9   21.5  70.7    -2.6    409  2.1
 11750    6.8  44.2   255   20   10   6.9   3.8   21.3  70.3    -2.8    387  2.0
 11500    7.3  45.1   250   19   10   8.4   4.6   21.1  70.0    -3.0    364  1.8
 11250    7.9  46.2   250   19   10   2.8   1.6   20.9  69.6    -3.3    341  1.7
 11000    7.8  46.0   245   19   10   1.6   0.9   20.1  68.2    -4.1    336  1.7
 10750    8.1  46.6   240   19   10   6.1   3.3   19.8  67.6    -4.5    319  1.6
 10500    8.5  47.3   235   18    9   5.3   2.9   19.4  66.9    -4.9    301  1.5
 10250    8.8  47.8   230   18    9   4.0   2.2   19.1  66.3    -5.3    283  1.4
 10000    9.0  48.2   230   18    9   2.6   1.4   18.5  65.3    -5.8    270  1.4
  9750    9.2  48.6   225   18    9   3.4   1.9   18.0  64.4    -6.4    257  1.3
  9500    9.4  48.9   220   18    9   3.4   1.8   17.5  63.5    -6.9    243  1.2
  9250    9.6  49.3   215   18    9   2.9   1.6   17.0  62.6    -7.5    230  1.2
  9000    9.8  49.6   215   17    9   2.5   1.4   16.5  61.7    -8.1    218  1.1
  8750    9.9  49.8   210   17    9   2.9   1.6   15.9  60.7    -8.6    205  1.0
  8500   10.1  50.2   205   18    9   3.0   1.6   15.4  59.8    -9.2    192  1.0
  8250   10.3  50.5   200   18    9   2.9   1.6   14.9  58.8    -9.8    179  0.9
  8000   10.5  50.9   195   17    9   1.9   1.0   14.4  57.8   -10.4    167  0.8
  7750   10.6  51.1   190   16    8   5.2   2.8   13.8  56.9   -11.0    155  0.8
  7500   11.0  51.8   190   15    8   1.1   0.6   13.5  56.3   -11.3    136  0.7
  7250   10.6  51.1   190   12    6  -9.6  -5.3   12.7  54.8   -12.2    140  0.7
  7000    9.9  49.8   190    9    4  -8.6  -4.7   11.6  53.0   -13.2    155  0.8
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           09/01/2014 at 0900 MDT          |       09/01/2014 at 1200 MDT
                                           |
K index... +6.5  LI... +2.3                | K index... +17.6  LI... +1.7
CAPE... 0.0  CIN... M                      | CAPE... +23.1  CIN... -18.3
                                           |
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 -63.1 -81.6  280  40 21   1.5   0.8 | -64.1 -83.4  280  44 23   0.0   0.0
 45000 -60.5 -76.9  280  62 32   2.6   1.4 | -62.5 -80.5  290  72 37   4.0   2.2
 40000 -56.1 -69.0  285  68 35   8.3   4.6 | -56.0 -68.8  295  73 38   8.8   4.8
 38000 -51.4 -60.5  285  68 35   7.7   4.2 | -51.0 -59.8  295  71 37   8.4   4.6
 36000 -46.8 -52.2  285  67 35   7.7   4.2 | -45.9 -50.6  295  69 36   8.4   4.6
 34000 -41.9 -43.4  280  66 34   8.3   4.6 | -41.1 -42.0  290  68 35   7.8   4.3
 32000 -36.3 -33.3  280  64 33   8.3   4.6 | -35.9 -32.6  285  67 35   7.7   4.2
 30000 -31.5 -24.7  280  62 32   7.8   4.3 | -31.2 -24.2  280  66 34   7.9   4.3
 29000 -29.2 -20.6  275  61 32   7.8   4.3 | -28.8 -19.8  280  66 34   7.9   4.3
 28000 -26.8 -16.2  275  60 31   7.7   4.2 | -26.5 -15.7  280  65 34   7.7   4.2
 27000 -24.5 -12.1  275  59 30   7.6   4.1 | -24.2 -11.6  280  64 33   7.5   4.1
 26000 -22.3  -8.1  275  57 29   7.6   4.2 | -22.0  -7.6  280  62 32   7.5   4.1
 25000 -20.0  -4.0  280  55 28   7.6   4.1 | -19.7  -3.5  280  60 31   7.4   4.1
 24000 -17.7   0.1  280  53 27   7.9   4.3 | -17.4   0.7  280  57 29   8.1   4.5
 23000 -15.3   4.5  280  51 26   7.9   4.3 | -15.0   5.0  275  52 27   8.1   4.5
 22000 -13.0   8.6  280  49 25   8.0   4.4 | -12.5   9.5  270  48 25   8.4   4.6
 21000 -10.9  12.4  280  48 25   6.7   3.7 | -10.6  12.9  275  50 26   6.1   3.3
 20000  -8.9  16.0  280  48 25   6.7   3.7 |  -8.8  16.2  280  53 27   6.1   3.4
 19500  -7.9  17.8  280  48 25   6.7   3.7 |  -7.9  17.8  280  54 28   6.1   3.3
 19000  -6.9  19.6  280  48 25   5.8   3.2 |  -7.0  19.4  280  56 29   4.8   2.6
 18500  -6.2  20.8  280  47 24   5.0   2.7 |  -6.4  20.5  285  54 28   3.9   2.1
 18000  -5.4  22.3  285  46 24   5.0   2.7 |  -5.9  21.4  285  53 27   4.0   2.2
 17500  -4.7  23.5  285  45 23   4.4   2.4 |  -5.5  22.1  285  51 26   2.1   1.2
 17000  -4.1  24.6  285  44 22   4.4   2.4 |  -5.2  22.6  285  50 26   2.4   1.3
 16500  -3.4  25.9  285  42 22   4.3   2.3 |  -4.8  23.4  285  49 25   4.2   2.3
 16000  -2.8  27.0  285  41 21   4.2   2.3 |  -4.1  24.6  285  45 23   5.4   2.9
 15500  -1.9  28.6  290  40 20   5.7   3.1 |  -2.9  26.8  285  38 20   7.8   4.3
 15000  -1.0  30.2  290  38 20   6.3   3.4 |  -1.7  28.9  285  34 17   8.3   4.6
 14500  -0.1  31.8  290  37 19   6.9   3.8 |  -0.5  31.1  285  29 15   8.8   4.8
 14000   1.0  33.8  290  34 18   7.8   4.3 |   0.8  33.4  285  26 13   9.2   5.1
 13500   2.1  35.8  285  32 16   8.2   4.5 |   2.2  36.0  285  23 12   9.3   5.1
 13000   3.4  38.1  285  29 15   9.2   5.1 |   3.6  38.5  285  21 11   9.5   5.2
 12500   4.7  40.5  280  26 13   8.8   4.8 |   5.0  41.0  285  19 10   8.6   4.7
 12000   6.0  42.8  275  24 12   9.3   5.1 |   6.3  43.3  285  17  9   9.7   5.3
 11750   6.7  44.1  275  23 12   9.2   5.0 |   7.1  44.8  285  17  9   9.7   5.3
 11500   7.4  45.3  275  21 11   9.1   5.0 |   7.8  46.0  285  16  8   8.6   4.7
 11250   8.0  46.4  270  21 11   8.3   4.6 |   8.3  46.9  285  15  8   7.7   4.2
 11000   8.6  47.5  270  20 11   8.3   4.5 |   8.9  48.0  285  14  7   9.2   5.0
 10750   9.2  48.6  270  20 10   8.7   4.7 |   9.6  49.3  285  13  7   9.7   5.3
 10500   9.9  49.8  265  19 10   8.9   4.9 |  10.4  50.7  285  13  7   9.7   5.3
 10250  10.4  50.7  265  19 10   5.4   3.0 |  11.0  51.8  285  12  6   5.2   2.8
 10000  10.7  51.3  260  18  9   4.5   2.5 |  11.2  52.2  280  11  5   6.9   3.8
  9750  11.1  52.0  260  18  9   7.1   3.9 |  12.0  53.6  275  10  5  11.8   6.5
  9500  11.6  52.9  255  18  9   6.5   3.6 |  12.8  55.0  275   8  4  10.3   5.7
  9250  11.9  53.4  250  17  9   2.7   1.5 |  13.5  56.3  270   7  4   8.5   4.7
  9000  11.9  53.4  245  17  9   0.1   0.0 |  14.0  57.2  265   7  3   7.6   4.2
  8750  11.9  53.4  240  17  9  -0.0  -0.0 |  14.7  58.5  260   6  3  10.3   5.6
  8500  11.8  53.2  235  17  9   0.0   0.0 |  15.5  59.9  255   6  3  11.1   6.1
  8250  11.7  53.1  225  16  8   2.2   1.2 |  16.3  61.3  250   5  3  10.1   5.6
  8000  11.9  53.4  220  15  8   2.5   1.4 |  17.0  62.6  245   5  3  10.4   5.7
  7750  12.0  53.6  210  14  7   4.0   2.2 |  17.8  64.0  245   5  2   8.9   4.9
  7500  12.4  54.3  195  13  7   7.8   4.3 |  18.4  65.1  240   4  2  10.3   5.6
  7250  13.0  55.4  195  12  6   9.3   5.1 |  19.3  66.7  235   4  2  14.2   7.8
  7000  13.7  56.7  195  12  6   9.1   5.0 |  20.4  68.7  235   4  2  13.1   7.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/01/2014 at 1500 MDT          |       09/01/2014 at 1800 MDT
                                           |
K index... +26.3  LI... -2.9               | K index... +24.5  LI... -1.0
CAPE... +90.4  CIN... -14.1                | CAPE... +42.1  CIN... -25.0
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.7 -86.3  285  43 22   0.7   0.4 | -65.8 -86.4  290  40 20   0.8   0.4
 45000 -62.8 -81.0  295  61 31   5.2   2.9 | -62.9 -81.2  295  58 30   5.0   2.8
 40000 -54.6 -66.3  300  65 34   8.3   4.6 | -55.0 -67.0  285  65 33   8.1   4.4
 38000 -49.6 -57.3  300  68 35   8.3   4.5 | -50.2 -58.4  290  65 33   8.0   4.4
 36000 -44.7 -48.5  300  70 36   8.3   4.5 | -45.4 -49.7  290  65 33   8.0   4.4
 34000 -40.1 -40.2  300  70 36   7.5   4.1 | -40.6 -41.1  295  64 33   8.0   4.4
 32000 -35.6 -32.1  300  70 36   7.5   4.1 | -35.2 -31.4  295  64 33   8.1   4.4
 30000 -30.5 -22.9  295  72 37   7.6   4.1 | -30.9 -23.6  295  63 32   6.9   3.8
 29000 -28.2 -18.8  295  74 38   7.6   4.1 | -28.9 -20.0  300  63 32   6.9   3.8
 28000 -26.0 -14.8  295  75 39   7.4   4.0 | -26.8 -16.2  300  62 32   7.9   4.3
 27000 -23.8 -10.8  295  74 38   7.1   3.9 | -24.2 -11.6  300  62 32   8.7   4.8
 26000 -21.7  -7.1  290  72 37   7.1   3.9 | -21.5  -6.7  300  62 32   8.7   4.8
 25000 -19.6  -3.3  290  71 37   7.2   3.9 | -18.9  -2.0  300  62 32   9.0   4.9
 24000 -17.5   0.5  285  69 36   6.6   3.6 | -16.9   1.6  300  60 31   6.1   3.4
 23000 -15.5   4.1  285  67 34   6.7   3.6 | -15.0   5.0  295  57 29   6.2   3.4
 22000 -13.6   7.5  285  65 33   7.1   3.9 | -13.2   8.2  295  55 28   6.2   3.4
 21000 -12.4   9.7  285  60 31   3.3   1.8 | -11.6  11.1  290  50 26   5.1   2.8
 20000 -11.5  11.3  280  54 28   3.5   1.9 | -10.1  13.8  290  44 23   5.1   2.8
 19500 -11.0  12.2  280  51 26   3.6   2.0 |  -9.4  15.1  285  42 21   5.1   2.8
 19000 -10.5  13.1  280  48 25   6.8   3.8 |  -8.7  16.3  285  39 20   5.1   2.8
 18500  -9.3  15.3  280  43 22   8.2   4.5 |  -8.0  17.6  280  35 18   5.5   3.0
 18000  -8.1  17.4  275  39 20   8.4   4.6 |  -7.3  18.9  275  31 16   6.4   3.5
 17500  -6.8  19.8  275  36 18   9.2   5.1 |  -6.2  20.8  275  28 15   9.6   5.3
 17000  -5.5  22.1  275  33 17   9.2   5.0 |  -4.8  23.4  275  27 14   9.4   5.2
 16500  -4.1  24.6  275  31 16   9.1   5.0 |  -3.4  25.9  275  25 13   9.2   5.0
 16000  -2.8  27.0  275  28 15   9.1   5.0 |  -2.1  28.2  275  23 12   9.2   5.0
 15500  -1.5  29.3  275  26 13   9.1   5.0 |  -0.0  32.0  280  21 11   9.2   5.1
 15000   0.5  32.9  280  22 12   9.1   5.0 |   1.4  34.5  280  19 10   9.2   5.1
 14500   1.9  35.4  280  20 10   9.1   5.0 |   2.7  36.9  280  18  9   9.3   5.1
 14000   3.3  37.9  280  18  9   9.1   5.0 |   4.1  39.4  285  16  8   9.3   5.1
 13500   4.6  40.3  280  17  9   9.2   5.0 |   5.5  41.9  285  14  7   9.4   5.2
 13000   6.0  42.8  280  14  7   9.3   5.1 |   6.9  44.4  285  12  6   9.6   5.2
 12500   7.3  45.1  275  12  6   8.8   4.8 |   8.3  46.9  290  10  5   8.5   4.7
 12000   8.6  47.5  275  10  5   9.0   4.9 |   9.6  49.3  290   9  5   9.3   5.1
 11750   9.3  48.7  275   9  5   9.4   5.2 |  10.2  50.4  295   8  4   9.4   5.2
 11500  10.0  50.0  270   9  4   7.4   4.0 |  10.9  51.6  295   7  4   8.1   4.4
 11250  10.4  50.7  265   8  4   8.0   4.4 |  11.5  52.7  295   6  3   8.4   4.6
 11000  11.2  52.2  265   7  4  10.6   5.8 |  12.2  54.0  300   6  3  10.0   5.5
 10750  11.9  53.4  260   7  3   9.9   5.4 |  12.9  55.2  300   5  3   9.6   5.3
 10500  12.7  54.9  255   6  3  10.1   5.5 |  13.6  56.5  310   4  2   9.5   5.2
 10250  13.4  56.1  250   6  3   8.2   4.5 |  14.3  57.7  315   4  2   7.6   4.2
 10000  13.9  57.0  250   5  3   9.1   5.0 |  14.8  58.6  315   4  2   9.1   5.0
  9750  14.7  58.5  245   5  3  11.2   6.1 |  15.6  60.1  325   3  2  11.4   6.3
  9500  15.5  59.9  240   5  2  10.6   5.8 |  16.4  61.5  335   3  2  10.6   5.8
  9250  16.3  61.3  235   4  2   9.8   5.4 |  17.2  63.0  345   3  2   9.2   5.0
  9000  17.0  62.6  235   4  2   9.4   5.2 |  17.8  64.0  345   3  1   8.7   4.8
  8750  17.7  63.9  230   4  2  10.4   5.7 |  18.5  65.3  350   3  1  10.2   5.6
  8500  18.5  65.3  225   4  2  10.7   5.9 |  19.3  66.7  360   3  1  10.4   5.7
  8250  19.3  66.7  220   4  2  10.2   5.6 |  20.0  68.0  005   3  1   9.8   5.4
  8000  20.1  68.2  220   4  2  10.4   5.7 |  20.8  69.4  005   3  1   9.8   5.4
  7750  20.8  69.4  215   4  2   9.5   5.2 |  21.5  70.7  010   3  1   9.5   5.2
  7500  21.5  70.7  210   4  2  10.2   5.6 |  22.1  71.8  020   3  1   8.0   4.4
  7250  22.3  72.1  205   3  2  12.9   7.1 |  22.6  72.7  020   3  1   6.6   3.6
  7000  23.3  73.9  205   3  2  12.8   7.0 |  23.1  73.6  025   3  1   6.6   3.6
  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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