Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 281131
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0431 MST Wednesday, January 28, 2015

This forecast is for Wednesday, January 28, 2015:

If the trigger temperature of 58.5 F/14.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 164 ft/min (0.8 m/s)
   Maximum height of thermals.................. 9647 ft MSL (2889 ft AGL)

Forecast maximum temperature................... 54.0 F/12.7 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1100 MST
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8587 ft MSL (1829 ft AGL)
Thermal soaring outlook for Thursday 01/29..... Poor

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 07:08:37 / 17:14:19 MST
Total possible sunshine........... 10 hr 5 min 42 sec (605 min 42 sec)
Altitude of sun at 12:11:50 MST... 32.97 degrees

Upper air data from numerical model forecast valid on 01/28/2015 at 0500 MST

Freezing level.................. 12616 ft MSL (5858 ft AGL)
Convective condensation level... 19249 ft MSL (12491 ft AGL)
Lifted condensation level....... 14957 ft MSL (8199 ft AGL)
Lifted index.................... +6.3
K index......................... -13.3

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  -62.9 -81.2   260   24   12   4.2   2.3      M     M       M      M    M
 45000  -56.5 -69.7   255   28   14   3.1   1.7      M     M       M      M    M
 40000  -51.9 -61.4   245   61   31   2.9   1.6      M     M       M      M    M
 38000  -51.6 -60.9   245   67   34  -0.3  -0.2      M     M       M      M    M
 36000  -51.9 -61.4   240   70   36  -0.4  -0.2      M     M       M      M    M
 34000  -50.3 -58.5   240   69   36   8.1   4.4      M     M       M      M    M
 32000  -45.4 -49.7   235   61   31   8.0   4.4      M     M       M      M    M
 30000  -40.2 -40.4   235   55   28   7.5   4.1   29.2  84.6    13.1      M    M
 29000  -37.9 -36.2   235   54   28   7.5   4.1   28.3  83.0    12.5      M    M
 28000  -35.7 -32.3   240   53   27   7.5   4.1   27.5  81.6    12.1      M    M
 27000  -33.3 -27.9   240   52   27   8.7   4.7   26.9  80.4    11.7      M    M
 26000  -30.7 -23.3   240   51   26   8.6   4.7   26.4  79.5    11.5      M    M
 25000  -28.1 -18.6   240   50   26   8.6   4.7   26.0  78.9    11.3      M    M
 24000  -25.6 -14.1   245   49   25   7.7   4.2   25.6  78.1    11.1      M    M
 23000  -23.3  -9.9   250   47   24   7.8   4.3   24.8  76.7    10.5      M    M
 22000  -20.9  -5.6   255   45   23   7.8   4.3   24.1  75.5    10.1      M    M
 21000  -18.5  -1.3   255   44   23   8.4   4.6   23.6  74.4     9.7      M    M
 20000  -16.0   3.2   260   44   23   8.4   4.6   23.0  73.5     9.4      M    M
 19500  -14.8   5.4   260   43   22   8.4   4.6   22.8  73.1     9.2      M    M
 19000  -13.5   7.7   265   43   22   8.5   4.7   22.6  72.7     9.1      M    M
 18500  -12.3   9.9   260   41   21   7.1   3.9   22.3  72.2     8.9      M    M
 18000  -11.3  11.7   260   37   19   7.1   3.9   21.9  71.4     8.6      M    M
 17500  -10.2  13.6   255   33   17   6.4   3.5   21.5  70.7     8.2      M    M
 17000   -9.4  15.1   245   28   14   5.7   3.1   20.8  69.4     7.6      M    M
 16500   -8.5  16.7   235   24   12   5.7   3.1   20.1  68.2     7.0      M    M
 16000   -7.8  18.0   225   21   11   4.8   2.7   19.3  66.8     6.4      M    M
 15500   -7.0  19.4   220   18    9   4.8   2.6   18.5  65.4     5.7      M    M
 15000   -5.7  21.7   215   14    7   7.2   3.9   17.6  63.8     4.9      M    M
 14500   -4.6  23.7   210   12    6   7.0   3.9   17.2  63.0     4.5      M    M
 14000   -3.4  25.9   205   11    5   8.9   4.9   16.9  62.5     4.2      M    M
 13500   -2.1  28.2   205   10    5   8.7   4.8   16.8  62.2     4.1      M    M
 13000   -0.8  30.6   200    9    5   9.2   5.0   16.6  61.9     4.0      M    M
 12500    0.6  33.1   200    8    4   8.9   4.9   16.5  61.8     3.9      M    M
 12000    1.6  34.9   215    7    4   6.3   3.5   16.1  61.0     3.5      M    M
 11750    2.1  35.8   235    8    4   7.5   4.1   15.9  60.6     3.3      M    M
 11500    2.6  36.7   250    9    4   6.8   3.7   15.7  60.2     3.1      M    M
 11250    3.2  37.8   260   10    5   8.7   4.8   15.5  59.9     2.9      M    M
 11000    3.8  38.8   265   11    6   5.9   3.2   15.4  59.7     2.8      M    M
 10750    4.0  39.2   275   15    7   2.1   1.1   14.9  58.7     2.3      M    M
 10500    4.2  39.6   280   18    9   2.8   1.5   14.3  57.8     1.8      M    M
 10250    4.4  39.9   285   22   11   3.7   2.1   13.8  56.8     1.2      M    M
 10000    4.7  40.5   285   26   13   3.5   1.9   13.4  56.1     0.8      M    M
  9750    4.8  40.6   290   29   15   0.9   0.5   12.8  55.0     0.2      M    M
  9500    4.8  40.6   290   32   17   0.2   0.1   12.0  53.7    -0.6    259  1.3
  9250    4.8  40.6   290   36   18   1.0   0.5   11.3  52.4    -1.3    252  1.3
  9000    4.8  40.6   290   37   19   1.7   0.9   10.7  51.3    -2.0    242  1.2
  8750    4.9  40.8   295   39   20   1.4   0.8   10.1  50.2    -2.6    232  1.2
  8500    5.0  41.0   295   38   19   1.1   0.6    9.4  49.0    -3.3    223  1.1
  8250    5.0  41.0   295   37   19   0.2   0.1    8.8  47.8    -4.0    216  1.1
  8000    4.9  40.8   295   34   17  -2.4  -1.3    7.9  46.3    -4.9    211  1.1
  7750    4.8  40.6   290   31   16   3.4   1.8    7.1  44.9    -5.7    207  1.1
  7500    5.2  41.4   290   26   13   2.1   1.2    6.8  44.3    -6.1    188  1.0
  7250    4.8  40.6   290   21   11 -11.6  -6.3    6.0  42.7    -7.0    193  1.0
  7000    3.7  38.7   290   16    8 -14.7  -8.1    4.6  40.3    -8.3    218  1.1
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           01/28/2015 at 0800 MST          |       01/28/2015 at 1100 MST
                                           |
K index... -10.5  LI... +2.8               | K index... -13.3  LI... +4.9
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 -62.0 -79.6  265  19 10   3.9   2.2 | -61.1 -78.0  265  25 13   4.4   2.4
 45000 -56.0 -68.8  260  23 12   4.8   2.6 | -54.7 -66.5  265  36 19   2.5   1.4
 40000 -48.5 -55.3  250  44 23   4.7   2.6 | -50.6 -59.1  250  47 24   2.6   1.4
 38000 -48.4 -55.1  250  52 27  -1.9  -1.0 | -50.6 -59.1  250  52 27  -1.5  -0.8
 36000 -49.6 -57.3  250  60 31  -1.9  -1.0 | -51.6 -60.9  255  57 29  -1.5  -0.8
 34000 -49.6 -57.3  245  65 33   4.5   2.5 | -51.3 -60.3  260  62 32   6.0   3.3
 32000 -46.8 -52.2  240  62 32   4.7   2.6 | -47.6 -53.7  260  67 34   6.3   3.4
 30000 -43.5 -46.3  240  59 31   7.5   4.1 | -43.4 -46.1  260  70 36   8.9   4.9
 29000 -40.7 -41.3  240  59 30   7.5   4.1 | -40.0 -40.0  260  70 36   9.0   4.9
 28000 -38.4 -37.1  245  58 30   7.5   4.1 | -37.4 -35.3  260  70 36   9.0   4.9
 27000 -36.1 -33.0  245  57 29   8.6   4.7 | -34.8 -30.6  260  69 36   7.7   4.2
 26000 -33.5 -28.3  250  55 28   8.5   4.7 | -32.4 -26.3  260  66 34   7.9   4.3
 25000 -31.0 -23.8  255  53 27   8.5   4.7 | -30.1 -22.2  255  63 32   7.9   4.3
 24000 -28.4 -19.1  255  51 26   8.7   4.8 | -27.7 -17.9  255  60 31   7.2   4.0
 23000 -25.8 -14.4  255  50 26   8.7   4.8 | -25.7 -14.3  255  57 29   7.0   3.9
 22000 -23.2  -9.8  255  48 25   8.7   4.8 | -23.6 -10.5  255  54 28   7.0   3.9
 21000 -20.6  -5.1  250  45 23   8.7   4.8 | -21.4  -6.5  255  51 26   8.2   4.5
 20000 -17.9  -0.2  250  42 22   8.7   4.8 | -19.0  -2.2  260  48 25   8.1   4.4
 19500 -16.6   2.1  245  40 21   8.7   4.8 | -17.7   0.1  260  47 24   8.1   4.4
 19000 -15.3   4.5  245  38 20   8.8   4.8 | -16.5   2.3  260  45 23   8.1   4.4
 18500 -14.1   6.6  240  36 19   7.5   4.1 | -15.3   4.5  260  44 23   8.3   4.6
 18000 -13.0   8.6  240  34 17   7.5   4.1 | -14.0   6.8  255  43 22   8.3   4.6
 17500 -11.9  10.6  235  31 16   7.1   3.9 | -12.8   9.0  255  43 22   8.4   4.6
 17000 -10.9  12.4  235  28 15   6.6   3.6 | -11.5  11.3  250  42 22   8.6   4.7
 16500  -9.9  14.2  235  25 13   6.6   3.6 | -10.2  13.6  250  41 21   8.7   4.8
 16000  -8.9  16.0  230  23 12   6.8   3.7 |  -9.0  15.8  250  39 20   7.5   4.1
 15500  -7.9  17.8  225  20 10   6.7   3.7 |  -7.9  17.8  250  37 19   7.6   4.1
 15000  -6.8  19.8  225  18  9   8.7   4.8 |  -6.8  19.8  255  35 18   4.7   2.6
 14500  -4.8  23.4  225  17  9   9.2   5.1 |  -6.1  21.0  275  31 16   3.6   2.0
 14000  -3.4  25.9  225  17  9   9.2   5.1 |  -5.8  21.6  285  31 16   0.5   0.3
 13500  -2.0  28.4  230  18  9   9.4   5.1 |  -5.8  21.6  300  32 16   0.3   0.2
 13000  -0.7  30.7  240  19 10   8.0   4.4 |  -5.5  22.1  310  34 18   4.5   2.5
 12500   0.5  32.9  250  22 11   9.5   5.2 |  -4.8  23.4  310  37 19   5.6   3.1
 12000   0.4  32.7  265  27 14  -6.6  -3.6 |  -4.2  24.4  310  39 20   2.7   1.5
 11750   0.3  32.5  275  31 16  -0.8  -0.4 |  -4.0  24.8  310  39 20   4.3   2.4
 11500   0.1  32.2  280  35 18  -2.3  -1.2 |  -3.7  25.3  310  39 20   3.8   2.1
 11250  -0.1  31.8  285  39 20  -2.1  -1.2 |  -3.4  25.9  305  39 20   4.4   2.4
 11000  -0.2  31.6  285  41 21  -0.7  -0.4 |  -3.1  26.4  305  37 19   5.4   3.0
 10750  -0.2  31.6  290  41 21   0.9   0.5 |  -2.7  27.1  305  35 18   5.6   3.1
 10500  -0.3  31.5  295  41 21   0.4   0.2 |  -2.3  27.9  305  33 17   5.6   3.1
 10250  -0.3  31.5  295  41 21   1.5   0.8 |  -1.9  28.6  305  31 16   5.8   3.2
 10000  -0.1  31.8  300  40 21   5.2   2.8 |  -1.5  29.3  305  29 15   7.0   3.8
  9750   0.4  32.7  300  39 20   8.3   4.5 |  -0.9  30.4  305  27 14   8.5   4.6
  9500   1.1  34.0  300  37 19   9.1   5.0 |  -0.3  31.5  305  24 13   9.0   5.0
  9250   1.7  35.1  300  36 18   7.9   4.4 |   0.4  32.7  310  22 12   8.3   4.6
  9000   2.2  36.0  300  34 18   6.7   3.7 |   0.9  33.6  310  20 11   7.3   4.0
  8750   2.7  36.9  305  32 17   6.9   3.8 |   1.5  34.7  310  19 10   9.0   4.9
  8500   3.2  37.8  305  30 16   7.0   3.8 |   2.2  36.0  310  17  9  10.3   5.6
  8250   3.6  38.5  305  28 14   4.6   2.5 |   2.9  37.2  315  15  8   9.2   5.1
  8000   3.8  38.8  305  25 13   1.2   0.7 |   3.6  38.5  315  13  7   8.7   4.8
  7750   4.0  39.2  305  23 12   6.5   3.6 |   4.2  39.6  315  11  6   9.2   5.0
  7500   4.5  40.1  310  19 10   3.4   1.9 |   4.9  40.8  320  10  5   8.2   4.5
  7250   4.2  39.6  310  16  8 -10.4  -5.7 |   5.4  41.7  320   9  5   6.4   3.5
  7000   3.2  37.8  305  12  6 -12.3  -6.8 |   5.8  42.4  320   8  4   6.5   3.6
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/28/2015 at 1400 MST          |       01/28/2015 at 1700 MST
                                           |
K index... +0.4  LI... +1.3                | K index... +1.8  LI... +1.8
CAPE... 0.0  CIN... -0.4                   | CAPE... 0.0  CIN... -0.5
                                           |
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 -60.1 -76.2  255  23 12   5.5   3.0 | -59.7 -75.5  265  23 12   5.5   3.0
 45000 -52.4 -62.3  265  30 16  -0.1  -0.1 | -52.0 -61.6  295  26 14  -0.3  -0.2
 40000 -51.7 -61.1  260  57 29   0.4   0.2 | -51.9 -61.4  280  49 25   0.1   0.0
 38000 -51.2 -60.2  260  63 33   1.2   0.6 | -51.7 -61.1  280  61 31   0.4   0.2
 36000 -50.5 -58.9  265  68 35   1.2   0.6 | -51.5 -60.7  280  75 39   0.4   0.2
 34000 -49.3 -56.7  270  73 38   4.6   2.5 | -50.5 -58.9  280  85 44   4.7   2.6
 32000 -46.6 -51.9  270  77 40   4.6   2.5 | -47.6 -53.7  285  77 40   4.8   2.6
 30000 -43.5 -46.3  270  79 41   7.4   4.1 | -44.0 -47.2  290  70 36   8.9   4.9
 29000 -41.3 -42.3  270  77 39   7.4   4.1 | -41.3 -42.3  295  69 35   8.9   4.9
 28000 -38.5 -37.3  270  73 38   7.4   4.1 | -38.6 -37.5  300  67 35   8.9   4.9
 27000 -36.3 -33.3  270  70 36   6.9   3.8 | -35.9 -32.6  305  67 34   8.0   4.4
 26000 -34.3 -29.7  270  68 35   6.8   3.7 | -33.6 -28.5  305  65 34   7.7   4.2
 25000 -32.2 -26.0  270  65 33   6.8   3.8 | -31.3 -24.3  305  64 33   7.7   4.2
 24000 -30.2 -22.4  270  62 32   6.7   3.7 | -29.0 -20.2  305  63 32   6.6   3.6
 23000 -28.2 -18.8  275  56 29   6.6   3.6 | -27.4 -17.3  305  56 29   5.3   2.9
 22000 -26.3 -15.3  275  50 26   6.6   3.6 | -25.8 -14.4  310  49 25   5.3   2.9
 21000 -24.3 -11.7  280  44 23   7.4   4.1 | -24.1 -11.4  310  42 22   6.7   3.7
 20000 -22.1  -7.8  285  38 19   7.4   4.1 | -22.0  -7.6  310  38 20   6.9   3.8
 19500 -21.0  -5.8  285  34 18   7.4   4.0 | -21.0  -5.8  310  36 18   6.9   3.8
 19000 -19.9  -3.8  285  31 16   7.3   4.0 | -20.0  -4.0  315  33 17   6.8   3.8
 18500 -18.6  -1.5  285  28 15   9.7   5.3 | -18.9  -2.0  315  31 16   7.4   4.1
 18000 -17.1   1.2  285  27 14  10.1   5.6 | -17.8  -0.0  315  29 15   7.6   4.2
 17500 -15.6   3.9  285  26 13   9.8   5.4 | -16.7   1.9  310  27 14   7.7   4.2
 17000 -14.2   6.4  285  25 13   8.5   4.7 | -15.5   4.1  310  25 13   8.1   4.5
 16500 -13.0   8.6  290  25 13   8.8   4.8 | -14.3   6.3  315  24 12   8.0   4.4
 16000 -11.8  10.8  295  25 13   6.6   3.6 | -12.4   9.7  315  23 12   8.9   4.9
 15500 -10.8  12.6  300  26 13   6.8   3.7 | -11.0  12.2  315  24 12   8.9   4.9
 15000  -9.9  14.2  310  27 14   5.5   3.0 |  -9.8  14.4  320  25 13   7.6   4.2
 14500  -9.1  15.6  320  28 14   5.1   2.8 |  -8.7  16.3  325  27 14   7.8   4.3
 14000  -7.9  17.8  330  30 15   7.1   3.9 |  -7.6  18.3  330  29 15   6.8   3.8
 13500  -6.9  19.6  330  31 16   7.0   3.8 |  -6.6  20.1  335  31 16   7.0   3.8
 13000  -6.0  21.2  325  32 16   6.3   3.5 |  -5.6  21.9  335  32 17   6.1   3.4
 12500  -5.1  22.8  325  33 17   6.7   3.7 |  -4.7  23.5  335  33 17   6.4   3.5
 12000  -4.4  24.1  320  33 17   4.2   2.3 |  -4.0  24.8  335  33 17   3.9   2.2
 11750  -4.0  24.8  320  33 17   5.8   3.2 |  -3.7  25.3  335  32 16   4.8   2.6
 11500  -3.6  25.5  315  33 17   5.1   2.8 |  -3.4  25.9  335  31 16   4.1   2.3
 11250  -3.2  26.2  315  33 17   6.4   3.5 |  -3.1  26.4  330  29 15   6.0   3.3
 11000  -2.7  27.1  315  31 16   8.0   4.4 |  -2.6  27.3  330  28 14   7.0   3.9
 10750  -2.1  28.2  310  30 15   7.9   4.3 |  -2.1  28.2  330  26 14   6.1   3.4
 10500  -1.5  29.3  310  28 15   8.2   4.5 |  -1.7  28.9  330  25 13   6.1   3.4
 10250  -1.0  30.2  310  27 14   7.2   4.0 |  -1.2  29.8  330  23 12   7.0   3.8
 10000  -0.5  31.1  305  25 13   7.7   4.2 |  -0.6  30.9  330  22 11   8.5   4.7
  9750   0.2  32.4  305  24 12  10.2   5.6 |   0.0  32.0  330  21 11   8.8   4.8
  9500   1.0  33.8  305  23 12  11.2   6.1 |   0.7  33.3  335  20 10   9.1   5.0
  9250   1.8  35.2  305  21 11   9.8   5.4 |   1.3  34.3  335  18 10   8.5   4.6
  9000   2.4  36.3  305  20 10   8.6   4.7 |   1.9  35.4  335  17  9   7.7   4.2
  8750   3.1  37.6  305  19 10   9.8   5.4 |   2.5  36.5  335  16  8   8.9   4.9
  8500   3.9  39.0  305  18  9  10.5   5.8 |   3.2  37.8  340  15  8   9.2   5.0
  8250   4.6  40.3  310  16  8   9.8   5.4 |   3.8  38.8  340  14  7   7.6   4.2
  8000   5.3  41.5  305  15  8   9.7   5.3 |   4.3  39.7  345  13  7   5.6   3.1
  7750   6.0  42.8  305  14  7   9.5   5.2 |   4.8  40.6  345  12  6  10.6   5.8
  7500   6.7  44.1  310  12  6   7.5   4.1 |   5.5  41.9  350  11  6   1.8   1.0
  7250   7.1  44.8  310  11  6   5.5   3.0 |   4.8  40.6  345   9  5 -14.0  -7.7
  7000   7.5  45.5  310  10  5   5.9   3.3 |   3.9  39.0  345   7  4  -6.2  -3.4
  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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