Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 191138
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0538 MDT Friday, September 19, 2014

This forecast is for Friday, September 19, 2014:

If the trigger temperature of 74.5 F/23.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 869 ft/min (4.4 m/s)
   Maximum height of thermals.................. 16072 ft MSL (9314 ft AGL)

Forecast maximum temperature................... 80.0 F/27.1 C
Time of trigger temperature.................... 1100 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................. 10718 ft MSL (3961 ft AGL)
Thermal soaring outlook for Saturday 09/20..... Good

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....................... 14369 ft MSL (7611 ft AGL)
Wave soaring outlook for Saturday 09/20........ Poor

Remarks...

Sunrise/Sunset.................... 06:44:00 / 19:02:19 MDT
Total possible sunshine........... 12 hr 18 min 19 sec (738 min 19 sec)
Altitude of sun at 12:52:40 MDT... 52.35 degrees

Upper air data from numerical model forecast valid on 09/19/2014 at 0600 MDT

Freezing level.................. 16074 ft MSL (9316 ft AGL)
Convective condensation level... 19187 ft MSL (12429 ft AGL)
Lifted condensation level....... 17800 ft MSL (11042 ft AGL)
Lifted index.................... +1.0
K index......................... +8.5

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  -67.3 -89.1   280   50   26   2.4   1.3      M     M       M      M    M
 45000  -61.6 -78.9   270   62   32   7.0   3.9      M     M       M      M    M
 40000  -51.0 -59.8   265   50   26   5.1   2.8      M     M       M      M    M
 38000  -47.9 -54.2   255   37   19   5.1   2.8      M     M       M      M    M
 36000  -44.8 -48.6   235   26   13   4.7   2.6      M     M       M      M    M
 34000  -40.3 -40.5   220   24   12   7.9   4.3      M     M       M      M    M
 32000  -35.6 -32.1   205   23   12   7.8   4.3      M     M       M      M    M
 30000  -30.8 -23.4   200   21   11   8.1   4.5   39.3 102.7     9.8      M    M
 29000  -28.4 -19.1   195   20   10   8.1   4.5   38.7 101.6     9.4      M    M
 28000  -25.9 -14.6   195   19   10   7.9   4.3   38.2 100.8     9.2      M    M
 27000  -23.1  -9.6   200   16    8   7.5   4.1   37.0  98.7     8.4      M    M
 26000  -20.9  -5.6   200   15    7   7.5   4.1   36.2  97.2     7.8      M    M
 25000  -18.7  -1.7   205   13    7   7.4   4.1   35.5  95.9     7.3      M    M
 24000  -16.5   2.3   215   12    6   7.3   4.0   34.5  94.1     6.5      M    M
 23000  -14.3   6.3   220   12    6   7.3   4.0   33.6  92.5     5.8      M    M
 22000  -12.2  10.0   230   12    6   7.0   3.9   32.8  91.1     5.2      M    M
 21000  -10.2  13.6   230   11    6   6.5   3.6   31.6  89.0     4.2      M    M
 20000   -8.3  17.1   230   10    5   6.5   3.6   30.5  87.0     3.3      M    M
 19500   -7.3  18.9   230   10    5   6.5   3.6   30.0  86.1     2.9      M    M
 19000   -6.3  20.7   235    9    5   6.9   3.8   29.5  85.2     2.4      M    M
 18500   -5.3  22.5   235    7    4   6.9   3.8   29.1  84.3     2.0      M    M
 18000   -4.3  24.3   245    5    3   6.8   3.7   28.6  83.5     1.6      M    M
 17500   -3.3  26.1   245    4    2   6.5   3.6   28.1  82.5     1.1      M    M
 17000   -2.4  27.7   240    2    1   6.4   3.5   27.5  81.6     0.6      M    M
 16500   -1.3  29.7   235    1    0   8.6   4.7   27.1  80.8     0.2      M    M
 16000   -0.0  32.0   000    0    0   8.6   4.7   26.9  80.5     0.0      M    M
 15500    1.2  34.2   080    1    1   8.7   4.8   26.8  80.2    -0.2    818  4.2
 15000    2.5  36.5   040    1    1   8.8   4.8   26.6  79.9    -0.4    765  3.9
 14500    3.7  38.7   020    2    1   8.8   4.8   26.4  79.6    -0.6    713  3.6
 14000    5.6  42.1   330    3    2   8.7   4.8   26.2  79.1    -1.0    636  3.2
 13500    6.8  44.2   315    5    2   8.8   4.8   26.0  78.8    -1.2    586  3.0
 13000    8.0  46.4   300    5    3   8.7   4.8   25.8  78.5    -1.5    533  2.7
 12500    9.3  48.7   290    6    3   8.1   4.5   25.7  78.3    -1.7    481  2.4
 12000   10.4  50.7   280    6    3   7.8   4.3   25.4  77.6    -2.0    432  2.2
 11750   11.0  51.8   275    6    3   7.8   4.3   25.2  77.4    -2.2    407  2.1
 11500   11.6  52.9   270    6    3   7.5   4.1   25.1  77.1    -2.3    383  1.9
 11250   12.1  53.8   260    7    3   6.6   3.6   24.8  76.7    -2.5    360  1.8
 11000   12.6  54.7   250    7    4   6.4   3.5   24.6  76.2    -2.8    338  1.7
 10750   13.0  55.4   240    8    4   6.5   3.6   24.3  75.8    -3.0    316  1.6
 10500   13.5  56.3   235    9    5   6.3   3.4   24.1  75.3    -3.3    294  1.5
 10250   14.0  57.2   230   10    5   5.2   2.9   23.8  74.8    -3.6    274  1.4
 10000   14.4  57.9   225   11    6   5.1   2.8   23.4  74.1    -3.9    255  1.3
  9750   14.8  58.6   220   12    6   5.7   3.1   23.1  73.5    -4.2    235  1.2
  9500   15.2  59.4   215   13    7   5.4   3.0   22.8  73.0    -4.6    215  1.1
  9250   15.6  60.1   215   14    7   4.9   2.7   22.4  72.3    -4.9    196  1.0
  9000   15.9  60.6   210   15    7   4.8   2.7   22.0  71.7    -5.3    178  0.9
  8750   16.3  61.3   210   16    8   6.3   3.4   21.7  71.1    -5.7    159  0.8
  8500   16.7  62.1   205   17    9   5.7   3.1   21.5  70.6    -6.0    139  0.7
  8250   17.0  62.6   205   16    8   4.2   2.3   21.1  69.9    -6.4    123  0.6
  8000   17.2  63.0   205   15    8   1.5   0.8   20.6  69.0    -7.0    110  0.6
  7750   17.4  63.3   205   14    7  10.0   5.5   20.1  68.2    -7.6     97  0.5
  7500   18.1  64.6   205   14    7  -0.8  -0.5   20.1  68.2    -7.6     68  0.3
  7250   16.9  62.4   210   11    6 -24.4 -13.4   18.6  65.4    -9.2     98  0.5
  7000   15.3  59.5   220    8    4 -14.1  -7.7   16.7  62.0   -11.1    139  0.7
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           09/19/2014 at 0900 MDT          |       09/19/2014 at 1200 MDT
                                           |
K index... +11.3  LI... +1.0               | K index... +13.5  LI... -0.1
CAPE... 0.0  CIN... -0.6                   | CAPE... +19.0  CIN... -35.7
                                           |
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 -67.1 -88.8  275  48 25   3.0   1.6 | -67.9 -90.2  270  50 26   3.4   1.9
 45000 -61.0 -77.8  270  65 34   6.9   3.8 | -61.1 -78.0  270  70 36   7.3   4.0
 40000 -50.5 -58.9  270  54 28   5.0   2.7 | -49.9 -57.8  270  62 32   5.4   3.0
 38000 -47.6 -53.7  265  42 21   4.9   2.7 | -46.7 -52.1  265  49 25   5.4   3.0
 36000 -44.6 -48.3  255  30 16   4.6   2.5 | -43.4 -46.1  260  36 19   5.3   2.9
 34000 -40.2 -40.4  240  26 13   7.9   4.3 | -39.6 -39.3  255  30 15   6.5   3.6
 32000 -35.4 -31.7  225  24 13   7.9   4.3 | -35.8 -32.4  250  24 12   6.5   3.5
 30000 -30.9 -23.6  215  23 12   7.5   4.1 | -31.2 -24.2  250  21 11   7.8   4.3
 29000 -28.7 -19.7  210  22 11   7.5   4.1 | -28.9 -20.0  250  19 10   7.8   4.3
 28000 -25.9 -14.6  210  21 11   7.5   4.1 | -26.0 -14.8  245  18  9   7.3   4.0
 27000 -23.6 -10.5  210  19 10   7.5   4.1 | -23.8 -10.8  245  17  8   7.2   3.9
 26000 -21.4  -6.5  210  17  9   7.5   4.1 | -21.7  -7.1  240  15  8   7.2   3.9
 25000 -19.1  -2.4  210  15  8   7.4   4.1 | -19.5  -3.1  240  14  7   7.2   3.9
 24000 -17.0   1.4  215  13  7   7.0   3.8 | -17.4   0.7  240  12  6   7.1   3.9
 23000 -14.9   5.2  215  11  6   7.0   3.8 | -15.3   4.5  240  10  5   7.1   3.9
 22000 -12.9   8.8  215   9  5   6.9   3.8 | -13.2   8.2  240   8  4   7.1   3.9
 21000 -10.9  12.4  220   8  4   6.7   3.7 | -11.1  12.0  240   7  4   7.0   3.9
 20000  -8.9  16.0  220   7  4   6.7   3.7 |  -9.0  15.8  240   5  3   7.1   3.9
 19500  -7.9  17.8  220   6  3   6.8   3.7 |  -8.0  17.6  240   5  2   7.2   3.9
 19000  -6.9  19.6  220   5  3   6.8   3.7 |  -7.0  19.4  235   4  2   6.5   3.6
 18500  -5.9  21.4  210   4  2   6.8   3.7 |  -6.0  21.2  220   3  1   6.6   3.6
 18000  -4.9  23.2  190   2  1   6.8   3.8 |  -5.0  23.0  195   2  1   6.9   3.8
 17500  -3.9  25.0  150   2  1   6.9   3.8 |  -4.0  24.8  165   2  1   7.4   4.0
 17000  -2.9  26.8  120   3  1   6.8   3.7 |  -2.9  26.8  135   2  1   7.3   4.0
 16500  -1.8  28.8  105   3  2   8.5   4.6 |  -1.8  28.8  110   2  1   8.2   4.5
 16000  -0.6  30.9  095   4  2   8.5   4.7 |  -0.7  30.7  085   3  2   8.3   4.5
 15500   0.7  33.3  085   5  3   8.4   4.6 |   0.4  32.7  075   5  2   8.5   4.7
 15000   1.8  35.2  070   6  3   8.4   4.6 |   1.7  35.1  065   5  3   8.7   4.8
 14500   3.0  37.4  055   6  3   8.6   4.7 |   2.9  37.2  055   6  3   8.9   4.9
 14000   4.9  40.8  030   6  3   9.1   5.0 |   4.9  40.8  045   7  4   9.3   5.1
 13500   6.2  43.2  015   7  3   9.4   5.2 |   6.3  43.3  040   8  4   9.2   5.0
 13000   7.6  45.7  010   6  3   9.7   5.3 |   7.7  45.9  030   8  4   9.1   5.0
 12500   9.1  48.4  360   6  3   9.0   4.9 |   9.0  48.2  020   9  4   7.5   4.1
 12000  10.4  50.7  355   6  3   8.9   4.9 |  10.1  50.2  015  10  5   8.9   4.9
 11750  11.1  52.0  350   6  3   9.0   4.9 |  10.8  51.4  015  10  5   8.8   4.8
 11500  11.7  53.1  345   6  3   8.1   4.4 |  11.4  52.5  010  10  5   8.2   4.5
 11250  12.3  54.1  335   5  3   7.5   4.1 |  12.0  53.6  010  10  5   8.3   4.5
 11000  12.8  55.0  325   5  2   8.1   4.4 |  12.6  54.7  010  10  5   9.1   5.0
 10750  13.4  56.1  315   5  2   8.0   4.4 |  13.3  55.9  005   9  5   9.0   4.9
 10500  14.0  57.2  310   5  3   7.7   4.2 |  13.9  57.0  005   9  5   8.6   4.7
 10250  14.5  58.1  295   5  3   6.2   3.4 |  14.5  58.1  360   8  4   7.4   4.1
 10000  15.0  59.0  285   5  3   6.5   3.6 |  15.1  59.2  355   7  4   8.6   4.7
  9750  15.5  59.9  275   6  3   7.8   4.3 |  15.8  60.4  360   7  3  10.1   5.6
  9500  16.1  61.0  265   6  3   6.9   3.8 |  16.5  61.7  360   6  3   9.1   5.0
  9250  16.5  61.7  255   7  3   5.1   2.8 |  17.0  62.6  360   5  3   7.2   4.0
  9000  16.8  62.2  245   7  4   4.4   2.4 |  17.5  63.5  360   4  2   7.5   4.1
  8750  17.2  63.0  240   7  4   5.2   2.9 |  18.2  64.8  005   3  2  10.2   5.6
  8500  17.5  63.5  235   8  4   4.3   2.4 |  19.0  66.2  010   3  1  10.8   5.9
  8250  17.8  64.0  230   8  4   2.4   1.3 |  19.8  67.6  015   2  1  10.0   5.5
  8000  17.9  64.2  225   8  4   1.6   0.9 |  20.5  68.9  020   2  1  10.2   5.6
  7750  18.0  64.4  225   8  4   2.8   1.6 |  21.2  70.2  025   2  1   9.4   5.2
  7500  18.2  64.8  220   8  4   2.8   1.5 |  21.9  71.4  035   2  1  10.8   5.9
  7250  18.3  64.9  220   7  3   1.3   0.7 |  22.8  73.0  040   2  1  13.3   7.3
  7000  18.3  64.9  220   6  3   2.2   1.2 |  23.7  74.7  045   2  1  11.8   6.5
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/19/2014 at 1500 MDT          |       09/19/2014 at 1800 MDT
                                           |
K index... +16.2  LI... -1.3               | K index... +23.3  LI... -1.9
CAPE... +178.5  CIN... -16.6               | CAPE... +248.1  CIN... -9.9
                                           |
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 -67.9 -90.2  270  52 27   3.2   1.8 | -67.4 -89.3  270  52 27   2.8   1.5
 45000 -61.3 -78.3  270  72 37   7.2   4.0 | -60.8 -77.4  270  72 37   7.2   3.9
 40000 -50.2 -58.4  270  66 34   6.0   3.3 | -50.2 -58.4  275  67 34   6.1   3.3
 38000 -46.6 -51.9  270  55 29   6.0   3.3 | -46.6 -51.9  275  57 30   6.1   3.3
 36000 -43.0 -45.4  270  45 23   6.0   3.3 | -43.0 -45.4  275  48 25   6.0   3.3
 34000 -39.2 -38.6  270  39 20   6.3   3.4 | -39.1 -38.4  275  42 22   6.5   3.6
 32000 -35.5 -31.9  265  33 17   6.3   3.4 | -35.2 -31.4  275  37 19   6.3   3.5
 30000 -31.0 -23.8  270  27 14   7.9   4.3 | -30.3 -22.5  280  30 15   7.6   4.2
 29000 -28.0 -18.4  270  22 11   7.9   4.3 | -28.0 -18.4  285  26 13   7.6   4.2
 28000 -25.6 -14.1  270  19 10   7.4   4.1 | -25.7 -14.3  285  23 12   7.6   4.2
 27000 -23.5 -10.3  270  17  9   7.3   4.0 | -23.5 -10.3  290  20 10   7.6   4.2
 26000 -21.3  -6.3  270  16  8   7.3   4.0 | -21.2  -6.2  290  18  9   7.6   4.2
 25000 -19.1  -2.4  270  15  8   7.2   4.0 | -18.9  -2.0  295  16  8   7.5   4.1
 24000 -17.0   1.4  270  14  7   6.7   3.7 | -16.7   1.9  295  14  7   7.2   4.0
 23000 -15.0   5.0  265  12  6   6.8   3.7 | -14.5   5.9  295  12  6   7.2   4.0
 22000 -13.0   8.6  260  11  6   6.7   3.7 | -12.3   9.9  295  11  6   6.8   3.8
 21000 -11.0  12.2  265  10  5   6.7   3.7 | -10.6  12.9  300  10  5   5.7   3.1
 20000  -9.1  15.6  270   8  4   6.8   3.7 |  -9.0  15.8  305  10  5   5.8   3.2
 19500  -8.1  17.4  275   7  4   6.7   3.7 |  -8.1  17.4  310  10  5   5.7   3.1
 19000  -7.0  19.4  275   7  4   7.8   4.3 |  -7.2  19.0  310  10  5   7.6   4.2
 18500  -5.9  21.4  275   6  3   7.8   4.3 |  -6.1  21.0  315  10  5   7.7   4.2
 18000  -4.7  23.5  275   6  3   7.7   4.2 |  -5.0  23.0  315  11  6   7.9   4.4
 17500  -3.6  25.5  275   5  3   7.5   4.1 |  -3.8  25.2  320  11  6   8.3   4.6
 17000  -2.5  27.5  270   4  2   7.5   4.1 |  -2.6  27.3  320  11  5   8.5   4.6
 16500  -1.4  29.5  275   3  2   7.7   4.2 |  -1.5  29.3  325  10  5   7.1   3.9
 16000  -0.4  31.3  305   2  1   7.7   4.2 |  -0.5  31.1  340   7  4   7.2   3.9
 15500   0.7  33.3  005   2  1   7.8   4.3 |   0.5  32.9  010   6  3   7.4   4.1
 15000   1.8  35.2  030   4  2   7.9   4.3 |   1.5  34.7  030   6  3   7.7   4.2
 14500   2.8  37.0  035   5  3   8.2   4.5 |   3.1  37.6  050   8  4   9.1   5.0
 14000   4.7  40.5  040   8  4   9.2   5.0 |   4.5  40.1  055   9  5   9.4   5.2
 13500   6.0  42.8  040   9  5   9.5   5.2 |   5.9  42.6  055   9  5   9.8   5.4
 13000   7.4  45.3  040   9  5   9.8   5.4 |   7.4  45.3  055  10  5  10.1   5.5
 12500   8.8  47.8  040   9  5   9.0   4.9 |   8.8  47.8  055  10  5   8.7   4.7
 12000  10.1  50.2  040   9  5   9.5   5.2 |  10.2  50.4  055  10  5  10.1   5.5
 11750  10.8  51.4  040   9  5   9.3   5.1 |  10.9  51.6  055  10  5   9.7   5.3
 11500  11.5  52.7  040   9  5   9.8   5.4 |  11.6  52.9  055  10  5  10.3   5.6
 11250  12.3  54.1  040   9  5   9.9   5.4 |  12.4  54.3  060  10  5   9.9   5.4
 11000  13.0  55.4  045   9  5   9.5   5.2 |  13.1  55.6  060  10  5   9.1   5.0
 10750  13.7  56.7  045   9  5   9.6   5.3 |  13.8  56.8  060  10  5   9.4   5.1
 10500  14.4  57.9  045   9  5   9.5   5.2 |  14.5  58.1  060  10  5   9.1   5.0
 10250  15.1  59.2  045   9  5   9.2   5.1 |  15.2  59.4  060  10  5   8.7   4.8
 10000  15.8  60.4  045   9  4   9.9   5.5 |  15.8  60.4  060  10  5   9.5   5.2
  9750  16.6  61.9  045   9  4  10.6   5.8 |  16.6  61.9  060  10  5  10.4   5.7
  9500  17.4  63.3  045   9  4  10.2   5.6 |  17.3  63.1  060  10  5   9.9   5.4
  9250  18.1  64.6  050   9  4   9.4   5.2 |  18.0  64.4  060  10  5   8.9   4.9
  9000  18.8  65.8  050   8  4   9.5   5.2 |  18.7  65.7  060   9  5   9.0   4.9
  8750  19.5  67.1  050   8  4  10.6   5.8 |  19.4  66.9  060   9  5  10.5   5.7
  8500  20.3  68.5  050   8  4  10.7   5.9 |  20.2  68.4  060   9  5  10.6   5.8
  8250  21.1  70.0  050   8  4  10.2   5.6 |  21.0  69.8  060   9  5   9.9   5.4
  8000  21.9  71.4  050   8  4  10.4   5.7 |  21.7  71.1  060   9  4   9.9   5.4
  7750  22.6  72.7  050   8  4   9.4   5.2 |  22.4  72.3  060   8  4   9.4   5.2
  7500  23.3  73.9  050   8  4  10.6   5.8 |  23.0  73.4  060   8  4   6.9   3.8
  7250  24.2  75.6  050   7  4  13.2   7.3 |  23.4  74.1  060   7  4   5.0   2.7
  7000  25.1  77.2  055   7  4  12.1   6.6 |  23.8  74.8  060   7  4   5.4   2.9
  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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