Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 111420
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0820 MDT Thursday, September 11, 2014

This forecast is for Thursday, September 11, 2014:

If the trigger temperature of 66.6 F/19.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 496 ft/min (2.5 m/s)
   Maximum height of thermals.................. 12268 ft MSL (5510 ft AGL)

Forecast maximum temperature................... 67.0 F/19.9 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................. 8327 ft MSL (1569 ft AGL)
Thermal soaring outlook for Friday 09/12....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 46382 ft MSL (39624 ft AGL)
Wave soaring outlook for Friday 09/12.......... Poor

Remarks...

Sunrise/Sunset.................... 06:36:49 / 19:15:07 MDT
Total possible sunshine........... 12 hr 38 min 17 sec (758 min 17 sec)
Altitude of sun at 12:55:29 MDT... 55.42 degrees

Upper air data from numerical model forecast valid on 09/11/2014 at 0600 MDT

Freezing level.................. 14021 ft MSL (7263 ft AGL)
Convective condensation level... 18191 ft MSL (11433 ft AGL)
Lifted condensation level....... 15212 ft MSL (8454 ft AGL)
Lifted index.................... +4.4
K index......................... -9.2

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  -65.1 -85.2   270   66   34   3.2   1.8      M     M       M      M    M
 45000  -59.7 -75.5   265   76   39   4.0   2.2      M     M       M      M    M
 40000  -53.5 -64.3   260   69   35   5.9   3.2      M     M       M      M    M
 38000  -50.1 -58.2   260   61   31   5.7   3.1      M     M       M      M    M
 36000  -46.7 -52.1   260   53   27   5.7   3.1      M     M       M      M    M
 34000  -42.4 -44.3   260   48   25   7.9   4.3      M     M       M      M    M
 32000  -37.6 -35.7   265   44   23   7.9   4.3      M     M       M      M    M
 30000  -32.3 -26.1   270   41   21   7.9   4.3   37.6  99.6    14.0      M    M
 29000  -29.9 -21.8   275   40   21   7.9   4.3   36.9  98.4    13.7      M    M
 28000  -27.6 -17.7   275   39   20   7.8   4.3   36.3  97.4    13.4      M    M
 27000  -25.3 -13.5   275   39   20   7.6   4.2   35.4  95.7    12.8      M    M
 26000  -23.0  -9.4   275   39   20   7.6   4.2   34.6  94.3    12.3      M    M
 25000  -20.7  -5.3   275   39   20   7.7   4.2   33.9  93.0    11.9      M    M
 24000  -18.7  -1.7   275   38   19   6.5   3.6   32.8  91.1    11.1      M    M
 23000  -16.7   1.9   275   36   19   6.5   3.6   31.6  88.9    10.2      M    M
 22000  -14.8   5.4   275   35   18   6.5   3.6   30.6  87.0     9.4      M    M
 21000  -12.8   9.0   275   33   17   6.7   3.7   29.4  84.9     8.6      M    M
 20000  -10.8  12.6   275   30   16   6.7   3.7   28.3  83.0     7.7      M    M
 19500   -9.8  14.4   275   29   15   6.7   3.7   27.8  82.1     7.3      M    M
 19000   -8.8  16.2   275   28   14   6.9   3.8   27.4  81.2     6.9      M    M
 18500   -7.8  18.0   275   26   14   7.0   3.9   26.9  80.4     6.5      M    M
 18000   -6.7  19.9   275   25   13   7.3   4.0   26.4  79.6     6.1      M    M
 17500   -5.9  21.4   270   24   12   4.2   2.3   25.7  78.3     5.6      M    M
 17000   -5.2  22.6   270   23   12   4.5   2.5   24.9  76.8     4.8      M    M
 16500   -4.5  23.9   270   22   11   4.8   2.6   24.0  75.2     4.1      M    M
 16000   -3.8  25.2   270   21   11   5.0   2.7   23.2  73.8     3.3      M    M
 15500   -3.1  26.4   270   20   10   5.3   2.9   22.4  72.4     2.5      M    M
 15000   -1.8  28.8   270   20   10   6.5   3.5   21.5  70.8     1.7      M    M
 14500   -0.9  30.4   270   20   10   7.5   4.1   21.0  69.8     1.1      M    M
 14000    0.3  32.5   270   19   10   8.4   4.6   20.8  69.4     0.9      M    M
 13500    1.6  34.9   270   19   10   8.2   4.5   20.6  69.1     0.7      M    M
 13000    2.8  37.0   275   18    9   7.5   4.1   20.3  68.5     0.4      M    M
 12500    3.9  39.0   275   17    9   7.1   3.9   19.9  67.9     0.1      M    M
 12000    5.1  41.2   280   16    8   9.1   5.0   19.7  67.4    -0.2    460  2.3
 11750    5.8  42.4   280   15    8   8.6   4.7   19.6  67.2    -0.2    433  2.2
 11500    6.4  43.5   280   15    8   9.4   5.2   19.5  67.1    -0.3    406  2.1
 11250    7.2  45.0   285   14    7  11.0   6.0   19.6  67.2    -0.3    376  1.9
 11000    8.0  46.4   285   13    7  10.6   5.8   19.7  67.4    -0.2    344  1.7
 10750    8.7  47.7   290   13    6  10.0   5.5   19.7  67.4    -0.2    315  1.6
 10500    9.4  48.9   290   12    6  10.1   5.5   19.7  67.5    -0.2    286  1.5
 10250   10.1  50.2   295   11    6   8.4   4.6   19.7  67.4    -0.3    259  1.3
 10000   10.6  51.1   300   11    6   8.6   4.7   19.6  67.2    -0.5    235  1.2
  9750   11.3  52.3   305   10    5  10.5   5.7   19.5  67.2    -0.5    207  1.0
  9500   12.0  53.6   310    9    5   8.9   4.9   19.6  67.2    -0.5    178  0.9
  9250   12.5  54.5   315    9    5   4.0   2.2   19.3  66.8    -0.8    157  0.8
  9000   12.6  54.7   320    8    4   1.6   0.9   18.8  65.8    -1.5    147  0.7
  8750   12.7  54.9   325    8    4   5.4   3.0   18.2  64.8    -2.0    135  0.7
  8500   13.1  55.6   335    8    4   2.6   1.4   17.9  64.3    -2.4    117  0.6
  8250   12.9  55.2   335    7    4  -5.3  -2.9   17.0  62.6    -3.4    116  0.6
  8000   12.4  54.3   335    7    3  -6.7  -3.7   15.8  60.4    -4.6    124  0.6
  7750   11.8  53.2   335    6    3  -6.5  -3.6   14.6  58.2    -5.9    133  0.7
  7500   11.1  52.0   325    5    3 -10.7  -5.9   13.2  55.8    -7.3    146  0.7
  7250   10.1  50.2   320    5    2 -14.2  -7.8   11.9  53.5    -8.7    169  0.9
  7000    9.1  48.4   320    4    2 -11.8  -6.5   10.6  51.1   -10.0    192  1.0
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           09/11/2014 at 0900 MDT          |       09/11/2014 at 1200 MDT
                                           |
K index... +2.3  LI... +3.3                | K index... +3.0  LI... +0.1
CAPE... 0.0  CIN... -0.7                   | CAPE... 0.0  CIN... -0.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.3 -85.5  270  60 31   3.6   2.0 | -65.7 -86.3  265  53 27   3.7   2.0
 45000 -59.1 -74.4  265  73 37   4.9   2.7 | -59.2 -74.6  265  70 36   5.5   3.0
 40000 -51.8 -61.2  260  69 35   3.7   2.0 | -51.1 -60.0  260  69 36   3.3   1.8
 38000 -49.5 -57.1  260  61 32   3.8   2.1 | -49.0 -56.2  260  65 33   3.5   1.9
 36000 -47.2 -53.0  260  54 28   3.9   2.1 | -46.9 -52.4  260  60 31   3.6   1.9
 34000 -43.3 -45.9  260  49 25   7.8   4.3 | -43.1 -45.6  260  55 28   7.5   4.1
 32000 -38.6 -37.5  260  46 23   7.8   4.3 | -38.6 -37.5  255  50 26   7.5   4.1
 30000 -33.1 -27.6  265  41 21   8.3   4.6 | -33.3 -27.9  260  45 23   8.1   4.5
 29000 -30.6 -23.1  265  40 20   8.3   4.6 | -30.8 -23.4  260  43 22   8.1   4.5
 28000 -28.1 -18.6  265  38 19   8.2   4.5 | -28.4 -19.1  265  41 21   8.1   4.5
 27000 -25.7 -14.3  270  37 19   7.7   4.2 | -26.3 -15.3  265  40 21   8.1   4.4
 26000 -23.4 -10.1  270  36 19   7.7   4.2 | -23.5 -10.3  265  39 20   8.1   4.4
 25000 -21.1  -6.0  270  35 18   7.8   4.3 | -21.1  -6.0  265  38 19   8.2   4.5
 24000 -19.0  -2.2  270  34 18   6.6   3.6 | -18.9  -2.0  270  37 19   6.8   3.7
 23000 -17.0   1.4  275  33 17   6.6   3.6 | -16.9   1.6  270  35 18   6.8   3.7
 22000 -15.0   5.0  275  32 17   6.6   3.6 | -14.9   5.2  270  34 18   6.8   3.8
 21000 -13.0   8.6  275  31 16   6.7   3.7 | -12.9   8.8  270  33 17   6.4   3.5
 20000 -11.0  12.2  275  30 15   6.7   3.7 | -11.0  12.2  270  32 16   6.4   3.5
 19500 -10.0  14.0  275  29 15   6.7   3.7 | -10.1  13.8  270  31 16   6.4   3.5
 19000  -9.1  15.6  275  28 15   6.1   3.4 |  -9.1  15.6  270  31 16   6.6   3.6
 18500  -8.2  17.2  275  28 14   5.8   3.2 |  -8.1  17.4  270  30 15   6.8   3.7
 18000  -7.4  18.7  275  27 14   5.9   3.2 |  -7.1  19.2  270  29 15   6.8   3.8
 17500  -6.6  20.1  275  26 13   5.0   2.8 |  -6.1  21.0  270  28 15   6.1   3.4
 17000  -5.8  21.6  270  25 13   5.1   2.8 |  -5.2  22.6  270  28 14   6.2   3.4
 16500  -5.1  22.8  270  24 12   5.0   2.8 |  -4.3  24.3  270  27 14   5.8   3.2
 16000  -4.4  24.1  265  23 12   5.0   2.8 |  -3.5  25.7  270  26 14   5.7   3.1
 15500  -3.7  25.3  265  22 11   5.5   3.0 |  -2.7  27.1  270  25 13   5.9   3.2
 15000  -2.3  27.9  260  20 10   6.8   3.8 |  -1.3  29.7  270  24 12   6.5   3.6
 14500  -1.4  29.5  255  19 10   7.7   4.2 |  -0.3  31.5  270  23 12   6.8   3.7
 14000  -0.1  31.8  255  18  9   8.2   4.5 |   0.7  33.3  270  22 11   7.1   3.9
 13500   1.1  34.0  255  17  9   8.3   4.5 |   1.6  34.9  270  21 11   7.5   4.1
 13000   2.3  36.1  255  16  8   8.3   4.6 |   2.8  37.0  265  19 10   8.3   4.5
 12500   3.5  38.3  255  15  8   8.3   4.5 |   3.9  39.0  260  17  9   7.9   4.3
 12000   4.8  40.6  255  13  7   8.7   4.8 |   5.1  41.2  260  16  8   9.3   5.1
 11750   5.4  41.7  255  13  7   8.8   4.8 |   5.7  42.3  255  15  8   9.1   5.0
 11500   6.0  42.8  255  12  6   8.6   4.7 |   6.4  43.5  255  14  7   9.0   4.9
 11250   6.6  43.9  255  11  6   7.7   4.2 |   7.0  44.6  250  14  7   7.0   3.9
 11000   7.1  44.8  255  10  5   6.9   3.8 |   7.4  45.3  250  13  7   5.2   2.8
 10750   7.6  45.7  260  10  5   7.0   3.9 |   7.7  45.9  245  12  6   5.3   2.9
 10500   8.1  46.6  260   9  5   6.6   3.6 |   8.0  46.4  245  12  6   4.7   2.6
 10250   8.6  47.5  260   9  4   5.7   3.1 |   8.2  46.8  240  11  5   0.3   0.2
 10000   8.9  48.0  265   8  4   4.0   2.2 |   8.1  46.6  240   9  5   0.3   0.2
  9750   9.1  48.4  270   7  3   2.8   1.5 |   8.2  46.8  230   8  4   3.6   2.0
  9500   9.2  48.6  275   5  3   1.6   0.9 |   8.4  47.1  215   6  3   3.1   1.7
  9250   9.2  48.6  285   4  2  -1.1  -0.6 |   8.5  47.3  195   6  3   2.3   1.2
  9000   9.0  48.2  305   4  2  -1.4  -0.8 |   8.6  47.5  175   5  3   2.3   1.2
  8750   8.8  47.8  330   3  2  -4.5  -2.5 |   8.9  48.0  155   5  3   8.4   4.6
  8500   8.3  46.9  355   5  2  -1.6  -0.9 |   9.7  49.5  140   6  3  12.0   6.6
  8250   8.5  47.3  360   6  3   4.9   2.7 |  10.5  50.9  135   6  3  10.3   5.6
  8000   8.8  47.8  360   7  4   4.0   2.2 |  11.3  52.3  130   6  3  10.5   5.7
  7750   9.1  48.4  005   8  4   6.3   3.5 |  12.1  53.8  130   7  3  10.7   5.9
  7500   9.7  49.5  005   9  4   8.9   4.9 |  12.9  55.2  125   7  4  12.7   7.0
  7250  10.4  50.7  005   8  4   8.4   4.6 |  13.9  57.0  120   7  4  14.0   7.7
  7000  11.0  51.8  005   8  4   9.0   4.9 |  14.9  58.8  120   7  4  13.0   7.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/11/2014 at 1500 MDT          |       09/11/2014 at 1800 MDT
                                           |
K index... +27.4  LI... -2.1               | K index... +27.2  LI... -3.5
CAPE... +314.3  CIN... -58.6               | CAPE... +405.7  CIN... -65.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.9 -86.6  260  56 29   3.9   2.1 | -66.2 -87.2  265  56 29   4.1   2.3
 45000 -58.9 -74.0  265  70 36   6.0   3.3 | -58.8 -73.8  265  67 35   6.3   3.5
 40000 -50.1 -58.2  260  67 34   2.6   1.4 | -49.5 -57.1  260  69 36   3.4   1.9
 38000 -48.3 -54.9  260  64 33   3.0   1.6 | -47.2 -53.0  260  66 34   3.8   2.1
 36000 -46.5 -51.7  255  62 32   3.0   1.7 | -45.0 -49.0  255  64 33   3.8   2.1
 34000 -43.1 -45.6  255  58 30   6.9   3.8 | -41.9 -43.4  260  61 31   5.8   3.2
 32000 -39.0 -38.2  255  53 27   6.9   3.8 | -38.4 -37.1  260  59 30   5.8   3.2
 30000 -33.8 -28.8  260  48 25   8.2   4.5 | -33.7 -28.7  265  55 28   7.7   4.2
 29000 -31.3 -24.3  260  47 24   8.2   4.5 | -31.4 -24.5  265  54 28   7.7   4.2
 28000 -28.8 -19.8  260  45 23   8.2   4.5 | -29.1 -20.4  265  52 27   7.7   4.2
 27000 -26.4 -15.5  260  44 22   8.2   4.5 | -26.8 -16.2  270  51 26   7.7   4.2
 26000 -23.9 -11.0  265  42 22   8.2   4.5 | -24.5 -12.1  270  50 26   7.7   4.2
 25000 -21.4  -6.5  265  41 21   8.3   4.6 | -22.2  -8.0  270  48 25   7.8   4.3
 24000 -19.2  -2.6  270  40 20   7.2   4.0 | -20.0  -4.0  270  47 24   6.8   3.7
 23000 -17.0   1.4  270  39 20   7.2   4.0 | -18.0  -0.4  270  46 24   6.8   3.7
 22000 -14.8   5.4  270  38 19   7.4   4.1 | -15.9   3.4  270  46 24   7.0   3.8
 21000 -13.1   8.4  270  38 19   5.5   3.0 | -14.2   6.4  275  44 23   5.4   3.0
 20000 -11.4  11.5  270  38 20   5.6   3.0 | -12.6   9.3  275  43 22   5.5   3.0
 19500 -10.6  12.9  270  39 20   5.6   3.1 | -11.8  10.8  275  42 22   5.6   3.1
 19000  -9.8  14.4  275  39 20   5.5   3.0 | -11.0  12.2  275  41 21   7.1   3.9
 18500  -9.0  15.8  275  38 20   5.5   3.0 |  -9.8  14.4  275  39 20   8.3   4.5
 18000  -8.2  17.2  275  38 19   5.6   3.1 |  -8.6  16.5  275  37 19   8.4   4.6
 17500  -7.4  18.7  275  36 19   7.3   4.0 |  -7.4  18.7  270  35 18   9.3   5.1
 17000  -6.4  20.5  270  33 17   7.4   4.1 |  -6.1  21.0  270  33 17   9.3   5.1
 16500  -5.4  22.3  270  31 16   8.5   4.7 |  -4.8  23.4  265  31 16   9.2   5.0
 16000  -4.1  24.6  270  28 15   9.0   4.9 |  -3.4  25.9  265  30 15   9.2   5.0
 15500  -2.8  27.0  265  26 13   9.1   5.0 |  -2.1  28.2  265  29 15   9.2   5.0
 15000  -0.9  30.4  265  24 12   9.0   4.9 |  -0.1  31.8  265  28 14   9.2   5.1
 14500   0.4  32.7  265  22 12   9.0   4.9 |   1.2  34.2  260  27 14   9.3   5.1
 14000   1.7  35.1  260  21 11   8.9   4.9 |   2.6  36.7  260  26 13   9.3   5.1
 13500   3.0  37.4  260  19 10   8.8   4.8 |   3.9  39.0  260  25 13   9.0   5.0
 13000   4.3  39.7  255  18  9   8.2   4.5 |   5.2  41.4  255  24 12   8.3   4.6
 12500   5.5  41.9  250  17  9   7.0   3.8 |   6.4  43.5  245  24 12   8.1   4.4
 12000   6.4  43.5  245  16  8   6.7   3.7 |   7.3  45.1  245  24 12   4.9   2.7
 11750   6.8  44.2  245  16  8   6.4   3.5 |   7.6  45.7  240  24 12   5.2   2.8
 11500   7.3  45.1  240  15  8   6.8   3.7 |   7.9  46.2  235  24 12   5.1   2.8
 11250   7.7  45.9  235  15  8   4.5   2.5 |   8.2  46.8  235  24 12   1.3   0.7
 11000   7.9  46.2  235  15  8   1.6   0.9 |   8.0  46.4  235  22 11  -1.5  -0.8
 10750   8.0  46.4  230  15  8   1.3   0.7 |   7.9  46.2  230  21 11  -0.7  -0.4
 10500   8.0  46.4  225  15  8   1.5   0.8 |   7.8  46.0  230  20 10  -0.6  -0.3
 10250   8.0  46.4  220  14  7  -2.3  -1.3 |   7.6  45.7  225  18  9  -3.0  -1.6
 10000   7.7  45.9  215  12  6   0.5   0.3 |   7.3  45.1  225  15  8  -1.5  -0.8
  9750   8.1  46.6  205  11  6   6.4   3.5 |   7.4  45.3  220  13  7   2.2   1.2
  9500   8.5  47.3  190  11  5   5.8   3.2 |   7.5  45.5  210  12  6   2.3   1.3
  9250   8.9  48.0  180  11  5   6.3   3.5 |   7.7  45.9  195  11  5   4.7   2.6
  9000   9.3  48.7  170  11  5   6.7   3.7 |   8.2  46.8  185  10  5   6.1   3.4
  8750   9.9  49.8  165  11  6   9.6   5.2 |   8.6  47.5  170   9  5   8.5   4.6
  8500  10.7  51.3  160  11  6  11.3   6.2 |   9.4  48.9  160  10  5  10.1   5.5
  8250  11.5  52.7  160  11  6  10.7   5.8 |  10.1  50.2  155  10  5   9.1   5.0
  8000  12.3  54.1  160  11  6  10.8   5.9 |  10.7  51.3  155  10  5   8.9   4.9
  7750  13.1  55.6  155  11  6  10.5   5.8 |  11.4  52.5  150  10  5   9.9   5.5
  7500  13.9  57.0  155  11  6  12.3   6.7 |  12.2  54.0  150  10  5   9.6   5.3
  7250  14.9  58.8  150  11  6  14.2   7.8 |  12.8  55.0  145  10  5   7.9   4.3
  7000  15.9  60.6  150  11  6  12.9   7.1 |  13.4  56.1  145  10  5   9.1   5.0
  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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