Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 271112
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0412 MST Tuesday, January 27, 2015

This forecast is for Tuesday, January 27, 2015:

If the trigger temperature of 61.7 F/16.5 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 267 ft/min (1.4 m/s)
   Maximum height of thermals.................. 11174 ft MSL (4416 ft AGL)

Forecast maximum temperature................... 62.0 F/17.1 C
Time of trigger temperature.................... 1415 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7722 ft MSL (964 ft AGL)
Thermal soaring outlook for Wednesday 01/28.... Fair

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

Remarks...

Sunrise/Sunset.................... 07:09:23 / 17:13:10 MST
Total possible sunshine........... 10 hr 3 min 47 sec (603 min 47 sec)
Altitude of sun at 12:11:38 MST... 32.71 degrees

Upper air data from numerical model forecast valid on 01/27/2015 at 0500 MST

Freezing level.................. 13162 ft MSL (6404 ft AGL)
Convective condensation level... 20320 ft MSL (13562 ft AGL)
Lifted condensation level....... 17216 ft MSL (10458 ft AGL)
Lifted index.................... +3.6
K index......................... +1.8

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  -64.8 -84.6   290   30   16   5.8   3.2      M     M       M      M    M
 45000  -57.3 -71.1   265   28   14  -0.9  -0.5      M     M       M      M    M
 40000  -58.5 -73.3   275   34   18  -1.3  -0.7      M     M       M      M    M
 38000  -56.3 -69.3   280   32   16   4.6   2.5      M     M       M      M    M
 36000  -53.5 -64.3   285   28   15   4.6   2.5      M     M       M      M    M
 34000  -49.9 -57.8   285   25   13   7.5   4.1      M     M       M      M    M
 32000  -45.4 -49.7   290   20   10   7.5   4.1      M     M       M      M    M
 30000  -40.2 -40.4   290   15    8   7.8   4.3   28.7  83.7     9.3      M    M
 29000  -37.9 -36.2   285   13    7   7.8   4.3   28.0  82.4     8.8      M    M
 28000  -35.5 -31.9   280   11    6   7.8   4.3   27.4  81.3     8.5      M    M
 27000  -33.0 -27.4   280   10    5   8.6   4.7   26.8  80.3     8.1      M    M
 26000  -30.4 -22.7   285   11    6   8.6   4.7   26.4  79.4     7.8      M    M
 25000  -27.8 -18.0   290   11    6   8.6   4.7   26.0  78.8     7.6      M    M
 24000  -25.2 -13.4   290   11    6   8.7   4.8   25.6  78.1     7.4      M    M
 23000  -22.6  -8.7   280   10    5   8.7   4.8   25.2  77.4     7.1      M    M
 22000  -20.0  -4.0   270    9    5   8.7   4.8   24.9  76.8     7.0      M    M
 21000  -17.5   0.5   265    8    4   8.4   4.6   24.4  76.0     6.6      M    M
 20000  -15.0   5.0   255    8    4   8.4   4.6   23.9  75.1     6.3      M    M
 19500  -13.7   7.3   250    7    4   8.4   4.6   23.7  74.7     6.1      M    M
 19000  -12.5   9.5   240    7    4   8.0   4.4   23.6  74.4     6.0      M    M
 18500  -11.3  11.7   240    7    4   7.8   4.3   23.2  73.7     5.7      M    M
 18000  -10.2  13.6   240    7    4   7.8   4.3   22.9  73.1     5.4      M    M
 17500   -9.1  15.6   240    8    4   7.3   4.0   22.5  72.5     5.1      M    M
 17000   -8.0  17.6   245    9    4   7.4   4.0   22.1  71.7     4.7      M    M
 16500   -6.9  19.6   245   10    5   6.9   3.8   21.7  71.0     4.4      M    M
 16000   -5.9  21.4   245   11    6   6.7   3.7   21.1  70.1     3.9      M    M
 15500   -5.0  23.0   250   12    6   6.5   3.6   20.6  69.2     3.4      M    M
 15000   -3.6  25.5   245   13    7   6.2   3.4   19.8  67.6     2.6      M    M
 14500   -2.7  27.1   245   13    7   6.9   3.8   19.2  66.6     2.1      M    M
 14000   -1.6  29.1   235   13    7   7.3   4.0   18.8  65.9     1.7      M    M
 13500   -0.5  31.1   230   13    7   7.3   4.0   18.4  65.2     1.3      M    M
 13000    0.6  33.1   225   14    7   7.3   4.0   18.0  64.4     1.0      M    M
 12500    1.7  35.1   220   14    7   7.5   4.1   17.6  63.8     0.6      M    M
 12000    2.8  37.0   215   15    8   8.2   4.5   17.4  63.3     0.3      M    M
 11750    3.5  38.3   215   15    8   8.1   4.4   17.2  63.0     0.2      M    M
 11500    4.1  39.4   215   16    8   8.3   4.6   17.1  62.8     0.1      M    M
 11250    4.7  40.5   215   16    8   8.6   4.7   17.0  62.6     0.0      M    M
 11000    5.3  41.5   215   16    8   8.5   4.6   16.9  62.5    -0.1    342  1.7
 10750    6.0  42.8   210   16    8   8.2   4.5   16.8  62.3    -0.2    316  1.6
 10500    6.6  43.9   210   16    8   8.6   4.7   16.7  62.1    -0.3    290  1.5
 10250    7.3  45.1   210   16    8   9.4   5.2   16.7  62.0    -0.4    263  1.3
 10000    8.0  46.4   215   16    8   9.2   5.1   16.6  61.9    -0.4    234  1.2
  9750    8.6  47.5   215   16    8   8.8   4.8   16.6  61.8    -0.5    207  1.1
  9500    9.3  48.7   215   16    8   8.7   4.8   16.5  61.7    -0.6    180  0.9
  9250    9.9  49.8   215   17    9   8.6   4.7   16.4  61.5    -0.6    154  0.8
  9000   10.6  51.1   215   17    9   8.4   4.6   16.3  61.4    -0.7    127  0.6
  8750   11.2  52.2   220   17    9  10.5   5.7   16.3  61.3    -0.8     99  0.5
  8500   12.0  53.6   220   16    8   6.8   3.7   16.3  61.3    -0.8     70  0.4
  8250   12.1  53.8   220   16    8  -1.4  -0.8   15.7  60.2    -1.4     58  0.3
  8000   12.2  54.0   225   15    8  10.9   6.0   15.1  59.2    -2.0     47  0.2
  7750   12.4  54.3   225   15    8 -30.3 -16.6   14.5  58.1    -2.6     35  0.2
  7500    8.0  46.4   230   14    7 -50.6 -27.8    9.7  49.5    -7.5    158  0.8
  7250    5.9  42.6   240   12    6 -17.7  -9.7    7.3  45.1   -10.0    213  1.1
  7000    3.8  38.8   255   10    5 -46.0 -25.2    4.8  40.7   -12.5    269  1.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           01/27/2015 at 0800 MST          |       01/27/2015 at 1100 MST
                                           |
K index... +2.2  LI... +3.7                | K index... +0.9  LI... +3.6
CAPE... 0.0  CIN... -0.8                   | CAPE... 0.0  CIN... -0.8
                                           |
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 -64.0 -83.2  300  29 15   5.0   2.8 | -63.8 -82.8  295  31 16   4.4   2.4
 45000 -57.2 -71.0  275  30 15   0.2   0.1 | -57.7 -71.9  280  36 18   1.6   0.9
 40000 -56.9 -70.4  275  37 19  -0.0  -0.0 | -55.2 -67.4  275  38 20   1.7   0.9
 38000 -55.1 -67.2  275  32 16   3.6   2.0 | -54.2 -65.6  270  32 16   1.8   1.0
 36000 -52.9 -63.2  275  25 13   3.6   2.0 | -53.1 -63.6  260  24 12   1.8   1.0
 34000 -49.7 -57.5  270  20 10   7.5   4.1 | -50.1 -58.2  245  21 11   8.6   4.7
 32000 -45.2 -49.4  265  16  8   7.5   4.1 | -44.3 -47.7  235  22 11   8.6   4.7
 30000 -40.0 -40.0  250  14  7   8.0   4.4 | -39.5 -39.1  230  22 11   7.6   4.1
 29000 -37.6 -35.7  245  14  7   8.0   4.4 | -37.2 -35.0  225  22 11   7.6   4.1
 28000 -35.2 -31.4  240  15  7   8.0   4.4 | -35.0 -31.0  225  21 11   7.5   4.1
 27000 -32.8 -27.0  240  14  7   8.1   4.4 | -32.6 -26.7  220  21 11   8.2   4.5
 26000 -30.4 -22.7  245  13  7   8.1   4.4 | -30.1 -22.2  220  21 11   8.2   4.5
 25000 -27.9 -18.2  250  12  6   8.1   4.5 | -27.7 -17.9  220  20 11   8.2   4.5
 24000 -25.4 -13.7  250  11  6   9.0   5.0 | -25.2 -13.4  220  20 10   8.7   4.8
 23000 -22.6  -8.7  245  11  6   9.1   5.0 | -22.5  -8.5  215  19 10   8.8   4.8
 22000 -19.9  -3.8  240  11  6   9.1   5.0 | -19.9  -3.8  215  17  9   8.8   4.8
 21000 -17.4   0.7  235  11  6   7.8   4.3 | -17.4   0.7  215  16  8   7.8   4.3
 20000 -15.1   4.8  230  11  6   7.8   4.3 | -15.1   4.8  215  16  8   7.8   4.3
 19500 -13.9   7.0  230  11  6   7.8   4.3 | -14.0   6.8  210  15  8   7.7   4.3
 19000 -12.8   9.0  225  11  6   7.8   4.3 | -12.8   9.0  210  15  8   7.5   4.1
 18500 -11.6  11.1  225  10  5   7.7   4.3 | -11.8  10.8  210  14  7   7.2   3.9
 18000 -10.5  13.1  225  10  5   7.8   4.3 | -10.7  12.7  210  13  7   7.1   3.9
 17500  -9.3  15.3  225   9  4   7.7   4.2 |  -9.6  14.7  210  12  6   7.5   4.1
 17000  -8.2  17.2  230   8  4   7.7   4.2 |  -8.5  16.7  210  12  6   7.5   4.1
 16500  -7.0  19.4  235   7  4   7.5   4.1 |  -7.4  18.7  210  11  6   7.5   4.1
 16000  -5.9  21.4  240   7  4   7.4   4.1 |  -5.7  21.7  210  10  5   7.5   4.1
 15500  -4.8  23.4  245   7  4   7.3   4.0 |  -4.5  23.9  215   9  5   7.8   4.3
 15000  -3.2  26.2  245   9  5   7.1   3.9 |  -3.4  25.9  215   9  5   7.8   4.3
 14500  -2.2  28.0  245  10  5   6.9   3.8 |  -2.2  28.0  220   9  5   7.6   4.2
 14000  -1.2  29.8  245  12  6   6.8   3.7 |  -1.1  30.0  225  10  5   7.5   4.1
 13500  -0.2  31.6  240  13  7   7.0   3.8 |  -0.0  32.0  225  11  6   7.5   4.1
 13000   0.9  33.6  240  13  7   7.4   4.0 |   1.1  34.0  230  11  6   7.7   4.2
 12500   1.9  35.4  235  13  7   7.4   4.1 |   2.2  36.0  230  12  6   7.6   4.2
 12000   3.1  37.6  235  13  7   8.3   4.6 |   3.4  38.1  230  12  6   7.9   4.3
 11750   3.7  38.7  230  13  7   8.2   4.5 |   3.9  39.0  230  12  6   7.8   4.3
 11500   4.3  39.7  230  13  7   8.4   4.6 |   4.5  40.1  230  11  6   7.9   4.3
 11250   4.9  40.8  230  13  7   8.7   4.8 |   5.1  41.2  230  11  6   8.0   4.4
 11000   5.6  42.1  225  13  7   8.2   4.5 |   5.7  42.3  230  11  6   7.8   4.3
 10750   6.2  43.2  225  13  7   7.8   4.3 |   6.3  43.3  230  11  6   7.7   4.2
 10500   6.7  44.1  225  13  7   8.1   4.4 |   6.8  44.2  230  11  6   7.8   4.3
 10250   7.4  45.3  225  13  7   8.8   4.9 |   7.4  45.3  225  11  6   7.9   4.3
 10000   8.0  46.4  220  14  7   8.7   4.8 |   8.0  46.4  225  11  6   7.9   4.4
  9750   8.7  47.7  220  14  7   8.1   4.4 |   8.6  47.5  225  11  6   7.9   4.3
  9500   9.3  48.7  220  14  7   8.1   4.4 |   9.2  48.6  225  11  6   7.7   4.2
  9250   9.9  49.8  220  13  7   8.2   4.5 |   9.7  49.5  225  11  6   7.4   4.1
  9000  10.5  50.9  220  13  7   8.0   4.4 |  10.3  50.5  220  11  6   7.2   3.9
  8750  11.1  52.0  220  13  7   8.4   4.6 |  10.9  51.6  220  11  6   8.6   4.7
  8500  11.6  52.9  215  13  6   5.1   2.8 |  11.5  52.7  220  11  6   6.4   3.5
  8250  11.8  53.2  220  12  6   0.9   0.5 |  11.7  53.1  220  10  5   2.7   1.5
  8000  11.9  53.4  220  11  6   2.9   1.6 |  11.9  53.4  225  10  5   3.6   2.0
  7750  12.0  53.6  220  11  6  -3.1  -1.7 |  12.1  53.8  225   9  5   1.1   0.6
  7500  10.9  51.6  225  11  6 -28.6 -15.7 |  11.5  52.7  225  10  5 -16.9  -9.3
  7250   7.9  46.2  235   9  5 -43.8 -24.0 |   9.4  48.9  240   8  4 -29.7 -16.3
  7000   4.9  40.8  255   8  4 -32.7 -17.9 |   7.3  45.1  255   7  4 -19.6 -10.7
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/27/2015 at 1400 MST          |       01/27/2015 at 1700 MST
                                           |
K index... -1.3  LI... +3.2                | K index... -4.8  LI... +3.7
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 -64.3 -83.7  290  34 17   4.0   2.2 | -64.6 -84.3  285  34 18   4.0   2.2
 45000 -58.4 -73.1  285  45 23   3.1   1.7 | -58.7 -73.7  280  43 22   3.7   2.0
 40000 -53.7 -64.7  280  47 24   3.2   1.8 | -53.1 -63.6  280  45 23   3.9   2.1
 38000 -52.7 -62.9  275  41 21   1.5   0.8 | -52.1 -61.8  275  44 22   1.1   0.6
 36000 -51.8 -61.2  270  33 17   1.5   0.8 | -51.4 -60.5  275  42 22   1.1   0.6
 34000 -48.8 -55.8  260  28 15   7.3   4.0 | -49.0 -56.2  270  40 21   7.8   4.3
 32000 -44.5 -48.1  245  29 15   7.3   4.0 | -43.8 -46.8  270  38 19   7.7   4.2
 30000 -39.6 -39.3  235  30 15   8.7   4.8 | -38.9 -38.0  270  36 18   8.4   4.6
 29000 -37.0 -34.6  230  30 15   8.7   4.8 | -36.4 -33.5  265  34 18   8.4   4.6
 28000 -34.4 -29.9  225  30 15   8.8   4.8 | -33.9 -29.0  265  33 17   8.4   4.6
 27000 -32.1 -25.8  220  29 15   7.1   3.9 | -31.5 -24.7  260  32 16   7.8   4.3
 26000 -30.0 -22.0  220  28 14   7.0   3.9 | -29.2 -20.6  250  31 16   7.8   4.3
 25000 -27.9 -18.2  215  26 13   7.1   3.9 | -26.9 -16.4  240  31 16   7.8   4.3
 24000 -25.5 -13.9  215  25 13   8.7   4.8 | -24.6 -12.3  235  30 16   7.6   4.2
 23000 -22.9  -9.2  215  24 12   8.7   4.8 | -22.2  -8.0  225  29 15   7.6   4.2
 22000 -20.3  -4.5  210  22 12   8.7   4.8 | -19.9  -3.8  220  29 15   7.7   4.2
 21000 -17.9  -0.2  210  22 11   7.4   4.1 | -17.7   0.1  215  28 14   7.5   4.1
 20000 -15.7   3.7  210  21 11   7.4   4.0 | -15.4   4.3  215  26 14   7.4   4.1
 19500 -14.6   5.7  210  20 11   7.4   4.0 | -14.3   6.3  215  26 13   7.4   4.1
 19000 -13.5   7.7  205  20 10   7.3   4.0 | -13.2   8.2  215  25 13   7.4   4.0
 18500 -12.4   9.7  205  19 10   7.2   3.9 | -12.1  10.2  215  24 12   7.0   3.8
 18000 -11.3  11.7  205  19 10   7.2   3.9 | -11.1  12.0  215  22 12   7.0   3.9
 17500 -10.2  13.6  205  18  9   7.6   4.2 | -10.0  14.0  215  21 11   7.1   3.9
 17000  -9.1  15.6  205  17  9   7.6   4.2 |  -9.0  15.8  215  20 10   7.1   3.9
 16500  -8.0  17.6  205  16  8   7.7   4.2 |  -7.9  17.8  215  18  9   7.1   3.9
 16000  -6.2  20.8  210  15  8   7.9   4.3 |  -6.3  20.7  215  17  9   7.2   3.9
 15500  -5.0  23.0  210  14  7   8.0   4.4 |  -5.3  22.5  215  15  8   7.6   4.2
 15000  -3.8  25.2  210  14  7   8.0   4.4 |  -4.1  24.6  215  14  7   7.9   4.3
 14500  -2.6  27.3  210  13  7   7.9   4.4 |  -2.9  26.8  215  13  7   7.9   4.3
 14000  -1.5  29.3  210  13  7   7.9   4.3 |  -1.7  28.9  215  12  6   7.8   4.3
 13500  -0.3  31.5  215  12  6   7.9   4.3 |  -0.6  30.9  215  10  5   7.8   4.3
 13000   0.9  33.6  215  12  6   8.0   4.4 |   0.7  33.3  215   9  5   8.6   4.7
 12500   2.1  35.8  220  11  6   8.0   4.4 |   1.9  35.4  220   8  4   7.9   4.3
 12000   3.3  37.9  225  11  5   8.1   4.5 |   3.0  37.4  220   7  4   7.9   4.3
 11750   3.9  39.0  225  10  5   8.2   4.5 |   3.6  38.5  220   7  4   7.8   4.3
 11500   4.5  40.1  225  10  5   8.0   4.4 |   4.2  39.6  225   7  4   7.7   4.2
 11250   5.1  41.2  230  10  5   7.5   4.1 |   4.8  40.6  225   7  3   8.5   4.7
 11000   5.6  42.1  230  10  5   8.0   4.4 |   5.4  41.7  225   7  3   8.4   4.6
 10750   6.2  43.2  230  10  5   8.5   4.7 |   6.0  42.8  230   6  3   7.6   4.2
 10500   6.9  44.4  230  11  5   8.3   4.6 |   6.6  43.9  230   6  3   7.9   4.3
 10250   7.5  45.5  235  11  6   7.4   4.1 |   7.2  45.0  235   6  3   7.5   4.1
 10000   8.0  46.4  235  11  6   7.4   4.1 |   7.7  45.9  235   6  3   7.3   4.0
  9750   8.6  47.5  235  11  6   8.2   4.5 |   8.3  46.9  240   6  3   7.6   4.2
  9500   9.2  48.6  235  11  6   8.1   4.4 |   8.8  47.8  250   6  3   7.6   4.2
  9250   9.8  49.6  235  11  6   7.7   4.2 |   9.4  48.9  255   6  3   7.4   4.0
  9000  10.3  50.5  235  11  6   7.4   4.1 |   9.9  49.8  260   7  3   7.1   3.9
  8750  10.9  51.6  235  11  6   8.4   4.6 |  10.4  50.7  265   7  4   8.1   4.4
  8500  11.5  52.7  235  11  6   6.7   3.7 |  11.0  51.8  270   8  4   6.9   3.8
  8250  11.8  53.2  235  11  5   3.8   2.1 |  11.4  52.5  270   9  5   3.6   2.0
  8000  12.0  53.6  240  10  5   3.5   1.9 |  11.5  52.7  270   9  5  -0.0  -0.0
  7750  12.2  54.0  240  10  5   4.3   2.3 |  11.6  52.9  270  10  5   9.0   4.9
  7500  12.0  53.6  235  10  5  -7.3  -4.0 |  12.1  53.8  265  10  5  -6.8  -3.7
  7250  10.7  51.3  245   8  4 -18.3 -10.0 |  10.1  50.2  270   9  5 -35.3 -19.4
  7000   9.4  48.9  255   6  3  -9.3  -5.1 |   7.6  45.7  275   8  4 -21.8 -11.9
  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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