Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 281116
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0516 MDT Monday, July 28, 2014

This forecast is for Monday, July 28, 2014:

If the trigger temperature of 72.1 F/22.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 166 ft/min (0.8 m/s)
   Maximum height of thermals.................. 11548 ft MSL (4378 ft AGL)

Forecast maximum temperature................... 73.0 F/23.2 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9591 ft MSL (2421 ft AGL)
Thermal soaring outlook for Tuesday 07/29...... Poor

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....................... 15555 ft MSL (8385 ft AGL)
Wave soaring outlook for Tuesday 07/29......... Poor

Remarks...

Sunrise/Sunset.................... 05:56:26 / 20:14:48 MDT
Total possible sunshine........... 14 hr 18 min 22 sec (858 min 22 sec)
Altitude of sun at 13:05:26 MDT... 69.89 degrees

Upper air data from numerical model forecast valid on 07/28/2014 at 0600 MDT

Freezing level.................. 16428 ft MSL (9258 ft AGL)
Convective condensation level... 13313 ft MSL (6143 ft AGL)
Lifted condensation level....... 12686 ft MSL (5515 ft AGL)
Lifted index.................... -1.6
K index......................... +25.6

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  -67.8 -90.0   290   13    6   1.5   0.8      M     M       M      M    M
 45000  -62.1 -79.8   280   23   12   7.1   3.9      M     M       M      M    M
 40000  -51.2 -60.2   260   25   13   8.0   4.4      M     M       M      M    M
 38000  -46.3 -51.3   260   22   11   8.0   4.4      M     M       M      M    M
 36000  -41.5 -42.7   265   19   10   7.9   4.4      M     M       M      M    M
 34000  -36.7 -34.1   255   17    9   7.9   4.4      M     M       M      M    M
 32000  -32.0 -25.6   250   16    8   8.4   4.6      M     M       M      M    M
 30000  -27.6 -17.7   260   11    6   7.3   4.0   43.2 109.8    15.8      M    M
 29000  -25.5 -13.9   270    9    5   7.3   4.0   42.3 108.2    15.3      M    M
 28000  -22.7  -8.9   285    8    4   7.6   4.1   41.3 106.3    14.6      M    M
 27000  -20.5  -4.9   295    9    5   7.6   4.2   40.4 104.7    14.0      M    M
 26000  -18.2  -0.8   300   10    5   7.6   4.2   39.6 103.3    13.5      M    M
 25000  -16.1   3.0   305   11    6   5.9   3.2   38.8 101.8    12.9      M    M
 24000  -14.3   6.3   310   11    5   5.9   3.3   37.3  99.2    11.8      M    M
 23000  -12.6   9.3   320   10    5   5.9   3.3   36.0  96.8    10.8      M    M
 22000  -10.8  12.6   330    9    5   6.0   3.3   34.7  94.4     9.8      M    M
 21000   -9.1  15.6   340    8    4   6.0   3.3   33.3  91.9     8.6      M    M
 20000   -7.4  18.7   360    7    4   6.1   3.3   32.0  89.7     7.6      M    M
 19500   -6.5  20.3   005    7    4   6.6   3.6   31.5  88.7     7.0      M    M
 19000   -5.5  22.1   015    7    4   7.0   3.9   31.0  87.8     6.6      M    M
 18500   -4.5  23.9   020    7    4   7.0   3.9   30.5  87.0     6.2      M    M
 18000   -3.4  25.9   020    8    4   7.4   4.1   30.1  86.2     5.9      M    M
 17500   -2.3  27.9   020    8    4   7.4   4.1   29.7  85.5     5.5      M    M
 17000   -1.3  29.7   015    8    4   7.3   4.0   29.3  84.8     5.1      M    M
 16500   -0.2  31.6   005    7    4   7.2   3.9   28.9  84.0     4.7      M    M
 16000    0.8  33.4   350    7    4   7.1   3.9   28.5  83.3     4.3      M    M
 15500    1.7  35.1   340    7    4   6.2   3.4   27.9  82.3     3.8      M    M
 15000    2.7  36.9   330    7    3   6.3   3.4   27.4  81.3     3.3      M    M
 14500    3.6  38.5   315    6    3   6.5   3.5   26.8  80.3     2.8      M    M
 14000    4.5  40.1   305    6    3   6.5   3.5   26.3  79.3     2.3      M    M
 13500    5.5  41.9   295    6    3   7.0   3.9   25.8  78.4     1.8      M    M
 13000    6.5  43.7   285    6    3   7.2   3.9   25.4  77.7     1.4      M    M
 12500    7.6  45.7   275    6    3   5.2   2.8   25.0  77.0     1.0      M    M
 12000    8.4  47.1   265    6    3   8.5   4.6   24.4  75.9     0.4      M    M
 11750    9.0  48.2   260    6    3   8.5   4.6   24.3  75.7     0.2      M    M
 11500    9.6  49.3   255    6    3   7.3   4.0   24.2  75.5     0.1      M    M
 11250   10.0  50.0   250    7    3   5.7   3.1   23.9  75.0    -0.2    351  1.8
 11000   10.4  50.7   245    7    4   6.2   3.4   23.6  74.5    -0.5    331  1.7
 10750   10.9  51.6   240    7    4   6.9   3.8   23.3  74.0    -0.8    309  1.6
 10500   11.4  52.5   240    7    4   6.0   3.3   23.1  73.6    -1.1    288  1.5
 10250   12.0  53.6   225    8    4   5.1   2.8   22.4  72.3    -1.9    253  1.3
 10000   12.3  54.1   220    9    4   3.7   2.0   22.0  71.6    -2.3    237  1.2
  9750   12.5  54.5   210    9    5   2.5   1.4   21.5  70.6    -2.9    225  1.1
  9500   12.6  54.7   205   10    5   2.7   1.5   20.9  69.6    -3.5    214  1.1
  9250   12.7  54.9   200   11    5   2.9   1.6   20.4  68.7    -4.1    202  1.0
  9000   12.9  55.2   195   11    6   2.0   1.1   19.8  67.7    -4.7    191  1.0
  8750   12.9  55.2   190   12    6   1.8   1.0   19.2  66.6    -5.4    182  0.9
  8500   13.0  55.4   185   13    7   2.5   1.4   18.6  65.6    -6.1    172  0.9
  8250   13.1  55.6   180   13    7   2.3   1.3   18.1  64.5    -6.7    161  0.8
  8000   13.2  55.8   180   14    7   2.5   1.4   17.5  63.6    -7.3    150  0.8
  7750   13.4  56.1   175   13    6   1.5   0.8   17.0  62.5    -7.9    139  0.7
  7500   13.4  56.1   175    9    5  -0.4  -0.2   16.3  61.3    -8.6    130  0.7
  7250   13.5  56.3   170    6    3   3.0   1.7   15.6  60.1    -9.3    122  0.6
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           07/28/2014 at 0900 MDT          |       07/28/2014 at 1200 MDT
                                           |
K index... +25.2  LI... -3.7               | K index... +26.0  LI... -4.0
CAPE... +668.0  CIN... -29.7               | CAPE... +887.0  CIN... -21.8
                                           |
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 -68.0 -90.4  275  10  5   1.1   0.6 | -67.0 -88.6  260  11  6  -0.0  -0.0
 45000 -62.7 -80.9  270  21 11   7.1   3.9 | -62.8 -81.0  265  21 11   7.1   3.9
 40000 -51.6 -60.9  260  24 12   8.4   4.6 | -51.7 -61.1  255  28 14   8.6   4.7
 38000 -46.6 -51.9  260  21 11   8.4   4.6 | -46.5 -51.7  255  28 14   8.6   4.7
 36000 -41.5 -42.7  265  19 10   8.1   4.5 | -41.3 -42.3  255  27 14   8.4   4.6
 34000 -36.6 -33.9  255  19 10   8.1   4.5 | -36.3 -33.3  255  25 13   8.3   4.6
 32000 -31.7 -25.1  245  20 10   8.6   4.7 | -31.3 -24.3  260  22 11   8.9   4.9
 30000 -27.3 -17.1  245  14  7   7.4   4.1 | -26.9 -16.4  265  18  9   7.4   4.1
 29000 -25.1 -13.2  240  11  6   7.4   4.1 | -24.7 -12.5  270  16  8   7.4   4.1
 28000 -23.0  -9.4  245   9  4   7.2   4.0 | -22.1  -7.8  275  13  7   6.6   3.6
 27000 -20.3  -4.5  260   8  4   7.3   4.0 | -20.1  -4.2  285  11  6   6.6   3.6
 26000 -18.1  -0.6  270   9  5   7.3   4.0 | -18.2  -0.8  295  10  5   6.6   3.6
 25000 -16.0   3.2  285   9  5   6.1   3.4 | -16.2   2.8  305   9  5   6.6   3.6
 24000 -14.2   6.4  295   9  4   6.2   3.4 | -14.2   6.4  315   9  5   6.6   3.6
 23000 -12.3   9.9  310   9  4   6.2   3.4 | -12.2  10.0  320  10  5   6.6   3.6
 22000 -10.5  13.1  320   9  4   5.1   2.8 | -10.3  13.5  330  10  5   5.3   2.9
 21000  -9.0  15.8  330   9  4   5.3   2.9 |  -8.8  16.2  330  11  6   5.5   3.0
 20000  -7.5  18.5  340   9  5   5.3   2.9 |  -7.2  19.0  335  11  6   5.5   3.0
 19500  -6.7  19.9  340   9  5   5.9   3.3 |  -6.4  20.5  335  12  6   5.7   3.1
 19000  -5.8  21.6  350  10  5   6.4   3.5 |  -5.6  21.9  340  12  6   5.8   3.2
 18500  -4.8  23.4  355  11  5   6.3   3.5 |  -4.8  23.4  345  12  6   5.8   3.2
 18000  -3.9  25.0  360  12  6   7.4   4.1 |  -3.9  25.0  355  12  6   6.1   3.4
 17500  -2.8  27.0  360  13  6   7.3   4.0 |  -3.1  26.4  360  13  7   6.1   3.4
 17000  -1.8  28.8  005  14  7   7.5   4.1 |  -2.2  28.0  005  13  7   7.0   3.8
 16500  -0.7  30.7  005  15  8   7.7   4.2 |  -1.1  30.0  010  13  7   7.7   4.2
 16000   0.4  32.7  005  16  8   7.7   4.2 |   0.1  32.2  015  13  7   7.8   4.3
 15500   1.5  34.7  005  16  8   7.6   4.2 |   1.2  34.2  020  13  7   8.3   4.5
 15000   2.6  36.7  005  17  9   7.6   4.2 |   2.4  36.3  025  13  7   8.3   4.6
 14500   3.7  38.7  005  16  8   7.7   4.2 |   3.5  38.3  025  13  6   7.4   4.0
 14000   4.9  40.8  005  15  8   7.7   4.2 |   4.6  40.3  030  12  6   7.4   4.0
 13500   6.0  42.8  360  13  7   7.5   4.1 |   5.7  42.3  035  11  6   7.4   4.1
 13000   7.1  44.8  360  11  6   7.4   4.1 |   6.8  44.2  035   9  5   7.3   4.0
 12500   8.1  46.6  355   9  4   5.1   2.8 |   7.8  46.0  035   8  4   5.3   2.9
 12000   8.9  48.0  350   6  3   7.9   4.3 |   8.7  47.7  025   6  3   8.7   4.8
 11750   9.5  49.1  345   5  2   8.1   4.4 |   9.3  48.7  020   5  3   8.6   4.7
 11500  10.0  50.0  335   4  2   6.2   3.4 |   9.9  49.8  010   5  3   7.3   4.0
 11250  10.3  50.5  310   3  1   3.6   2.0 |  10.3  50.5  355   4  2   5.1   2.8
 11000  10.6  51.1  270   2  1   5.3   2.9 |  10.7  51.3  340   4  2   6.7   3.7
 10750  11.0  51.8  240   3  2   7.5   4.1 |  11.3  52.3  320   4  2   8.8   4.8
 10500  11.5  52.7  225   4  2   4.6   2.5 |  11.8  53.2  305   4  2   6.5   3.6
 10250  11.7  53.1  215   7  4   1.9   1.1 |  12.4  54.3  265   5  3   4.3   2.4
 10000  11.8  53.2  215   9  4   1.4   0.8 |  12.6  54.7  255   7  3   3.9   2.1
  9750  11.8  53.2  215  11  5   2.3   1.2 |  12.8  55.0  245   8  4   2.6   1.4
  9500  12.0  53.6  210  11  6   2.9   1.6 |  12.9  55.2  230  10  5   2.0   1.1
  9250  12.2  54.0  205  12  6   3.7   2.0 |  13.0  55.4  220  11  6   1.7   0.9
  9000  12.3  54.1  205  13  7   0.4   0.2 |  13.0  55.4  210  13  7   3.7   2.0
  8750  12.2  54.0  200  14  7   3.8   2.1 |  13.4  56.1  205  15  8   7.8   4.3
  8500  12.8  55.0  195  14  7   9.5   5.2 |  14.0  57.2  200  15  8   8.9   4.9
  8250  13.3  55.9  190  14  7   8.4   4.6 |  14.6  58.3  190  15  8   8.5   4.7
  8000  13.9  57.0  180  14  7   7.3   4.0 |  15.2  59.4  185  15  8   9.0   4.9
  7750  14.4  57.9  180  13  7  11.7   6.4 |  16.0  60.8  185  14  7  14.9   8.2
  7500  15.7  60.3  175  12  6  23.4  12.9 |  17.4  63.3  180  13  7  23.4  12.8
  7250  16.9  62.4  170  11  6   1.2   0.7 |  18.8  65.8  180  13  6   8.8   4.8
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/28/2014 at 1500 MDT          |       07/28/2014 at 1800 MDT
                                           |
K index... +21.3  LI... -3.4               | K index... +8.2  LI... -3.9
CAPE... +893.0  CIN... -21.6               | CAPE... +1064.7  CIN... -17.6
                                           |
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 -67.0 -88.6  265  17  9   0.9   0.5 | -66.7 -88.1  285  20 10   1.2   0.7
 45000 -62.3 -80.1  270  26 13   6.4   3.5 | -61.9 -79.4  285  30 15   6.2   3.4
 40000 -52.0 -61.6  265  29 15   8.8   4.8 | -51.9 -61.4  290  32 16   8.5   4.7
 38000 -46.8 -52.2  265  29 15   8.8   4.8 | -46.7 -52.1  290  31 16   8.5   4.7
 36000 -41.5 -42.7  265  28 15   8.4   4.6 | -41.6 -42.9  290  31 16   8.4   4.6
 34000 -36.5 -33.7  270  27 14   8.3   4.6 | -36.6 -33.9  290  29 15   8.4   4.6
 32000 -31.5 -24.7  275  25 13   9.0   4.9 | -31.5 -24.7  290  27 14   9.1   5.0
 30000 -26.9 -16.4  285  21 11   7.7   4.2 | -26.9 -16.4  295  21 11   7.8   4.3
 29000 -24.6 -12.3  295  19 10   7.8   4.3 | -24.6 -12.3  295  18  9   7.8   4.3
 28000 -21.9  -7.4  300  16  8   6.4   3.5 | -21.9  -7.4  300  14  7   6.2   3.4
 27000 -20.0  -4.0  310  13  7   6.4   3.5 | -20.1  -4.2  305  11  6   6.2   3.4
 26000 -18.1  -0.6  320  10  5   6.4   3.5 | -18.3  -0.9  320   8  4   6.2   3.4
 25000 -16.2   2.8  335   8  4   6.6   3.6 | -16.5   2.3  335   7  4   5.9   3.3
 24000 -14.3   6.3  335   8  4   6.6   3.6 | -14.7   5.5  340   7  3   5.9   3.3
 23000 -12.3   9.9  330   8  4   6.6   3.6 | -12.9   8.8  345   7  3   5.9   3.3
 22000 -10.4  13.3  330   9  4   6.3   3.5 | -11.1  12.0  350   7  3   6.9   3.8
 21000  -8.5  16.7  340   9  5   6.4   3.5 |  -9.0  15.8  355   7  4   6.9   3.8
 20000  -6.6  20.1  350  10  5   6.3   3.5 |  -6.9  19.6  005   8  4   6.8   3.7
 19500  -5.6  21.9  350  11  5   5.4   3.0 |  -5.8  21.6  005   8  4   6.0   3.3
 19000  -5.0  23.0  360  11  6   4.6   2.5 |  -5.0  23.0  015   9  5   5.2   2.9
 18500  -4.3  24.3  005  12  6   4.3   2.4 |  -4.2  24.4  025  10  5   5.1   2.8
 18000  -3.5  25.7  010  13  7   6.0   3.3 |  -3.3  26.1  030  11  6   6.7   3.7
 17500  -2.7  27.1  015  13  7   6.0   3.3 |  -2.3  27.9  035  12  6   6.6   3.6
 17000  -1.8  28.8  020  13  7   6.9   3.8 |  -1.3  29.7  035  13  7   6.8   3.7
 16500  -0.7  30.7  025  12  6   7.7   4.2 |  -0.3  31.5  040  12  6   7.2   4.0
 16000   0.4  32.7  030  12  6   7.9   4.3 |   0.7  33.3  040  11  6   7.5   4.1
 15500   1.6  34.9  035  11  6   8.5   4.7 |   1.8  35.2  040  10  5   8.6   4.7
 15000   2.8  37.0  040   9  5   8.5   4.7 |   3.0  37.4  040   8  4   8.7   4.7
 14500   4.0  39.2  050   8  4   7.7   4.2 |   4.2  39.6  045   6  3   8.6   4.7
 14000   5.1  41.2  055   7  4   7.7   4.2 |   5.4  41.7  045   5  3   8.6   4.7
 13500   6.2  43.2  060   7  3   7.1   3.9 |   6.6  43.9  045   4  2   7.6   4.2
 13000   7.1  44.8  060   5  3   6.8   3.7 |   7.6  45.7  030   4  2   7.2   4.0
 12500   8.1  46.6  055   4  2   6.6   3.6 |   8.6  47.5  010   4  2   6.5   3.6
 12000   9.1  48.4  015   3  2   7.3   4.0 |   9.5  49.1  340   5  3   7.9   4.3
 11750   9.6  49.3  355   3  2   7.1   3.9 |  10.0  50.0  325   6  3   7.7   4.2
 11500  10.0  50.0  340   4  2   7.3   4.0 |  10.5  50.9  315   7  3   8.0   4.4
 11250  10.5  50.9  325   5  3   7.3   4.0 |  11.0  51.8  310   8  4   8.3   4.6
 11000  11.1  52.0  315   6  3   8.3   4.5 |  11.6  52.9  305   8  4   8.6   4.7
 10750  11.7  53.1  310   6  3   9.1   5.0 |  12.2  54.0  305   8  4   8.7   4.8
 10500  12.3  54.1  300   7  4   9.0   5.0 |  12.8  55.0  300   8  4   8.9   4.9
 10250  13.6  56.5  285   7  4   9.1   5.0 |  14.1  57.4  290   7  4   9.3   5.1
 10000  14.2  57.6  280   7  4   9.7   5.3 |  14.8  58.6  280   7  4   9.5   5.2
  9750  14.9  58.8  285   7  4   7.0   3.8 |  15.4  59.7  280   6  3   8.1   4.4
  9500  15.2  59.4  270   7  3   4.0   2.2 |  15.9  60.6  270   6  3   6.5   3.6
  9250  15.4  59.7  255   7  3   3.6   2.0 |  16.4  61.5  255   5  3   6.0   3.3
  9000  15.6  60.1  240   7  4   6.4   3.5 |  16.8  62.2  240   5  3   8.1   4.5
  8750  16.2  61.2  225   8  4   9.4   5.2 |  17.5  63.5  225   6  3  10.1   5.5
  8500  16.9  62.4  220   8  4   8.7   4.8 |  18.2  64.8  220   6  3   9.2   5.1
  8250  17.5  63.5  215   8  4   9.0   4.9 |  18.9  66.0  215   6  3   9.6   5.2
  8000  18.1  64.6  210   8  4   8.9   4.9 |  19.6  67.3  205   6  3   8.9   4.9
  7750  18.9  66.0  205   8  4  13.5   7.4 |  20.2  68.4  200   6  3  11.4   6.3
  7500  20.2  68.4  200   7  4  21.1  11.6 |  21.3  70.3  200   6  3  17.4   9.6
  7250  21.5  70.7  200   7  4   7.7   4.2 |  22.3  72.1  195   6  3   6.2   3.4
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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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