Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 261350
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0750 MDT Saturday, May 26, 2018

This forecast is for Saturday, May 26, 2018:

If the trigger temperature of 76.3 F/24.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 2055 ft/min (10.4 m/s)
   Maximum height of thermals.................. 27236 ft MSL (19645 ft AGL)

Forecast maximum temperature................... 87.0 F/31.0 C
Time of trigger temperature.................... 0945 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................. 20957 ft MSL (13366 ft AGL)
Thermal soaring outlook for Sunday 05/27....... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:38:18 / 20:14:25 MDT
Total possible sunshine........... 14 hr 36 min 7 sec (876 min 7 sec)
Altitude of sun at 12:56:21 MDT... 72.21 degrees

Upper air data from numerical model forecast valid on 05/26/2018 at 0600 MDT

Freezing level.................. 16008 ft MSL (8417 ft AGL)
Convective condensation level... 19708 ft MSL (12117 ft AGL)
Lifted condensation level....... 21419 ft MSL (13828 ft AGL)
Lifted index.................... -4.8
K index......................... +11.3

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -62.5 -80.5   250   15    8   1.8   1.0      M     M       M      M    M
 45000  -59.9 -75.8   255   22   11   0.8   0.4      M     M       M      M    M
 40000  -58.6 -73.5   250   17    9   5.4   2.9      M     M       M      M    M
 38000  -54.3 -65.7   245   15    8   7.1   3.9      M     M       M      M    M
 36000  -50.1 -58.2   235   13    7   7.1   3.9      M     M       M      M    M
 34000  -45.7 -50.3   230   13    6   7.5   4.1      M     M       M      M    M
 32000  -40.7 -41.3   230   13    6   7.5   4.1      M     M       M      M    M
 30000  -35.7 -32.3   225   12    6   8.6   4.7   31.7  89.0     0.9      M    M
 29000  -33.1 -27.6   225   12    6   8.7   4.7   31.3  88.3     0.6      M    M
 28000  -30.5 -22.9   225   12    6   8.6   4.7   31.0  87.8     0.4      M    M
 27000  -28.0 -18.4   230   11    6   8.4   4.6   30.4  86.8    -0.1   2029 10.3
 26000  -25.5 -13.9   235   11    6   8.4   4.6   29.9  85.8    -0.5   1925  9.8
 25000  -23.0  -9.4   235   10    5   8.4   4.6   29.5  85.1    -0.9   1820  9.2
 24000  -20.5  -4.9   240   10    5   8.2   4.5   28.9  84.1    -1.4   1716  8.7
 23000  -18.1  -0.6   240    9    5   8.2   4.5   28.3  83.0    -1.9   1614  8.2
 22000  -15.6   3.9   245    9    4   8.2   4.5   27.8  82.1    -2.4   1511  7.7
 21000  -13.2   8.2   240    8    4   8.2   4.5   27.3  81.1    -2.9   1409  7.2
 20000  -10.8  12.6   235    7    3   8.2   4.5   26.7  80.1    -3.5   1307  6.6
 19500   -9.0  15.8   235    6    3   8.3   4.5   26.4  79.5    -3.8   1230  6.2
 19000   -7.8  18.0   230    6    3   8.4   4.6   26.2  79.1    -4.1   1179  6.0
 18500   -6.5  20.3   225    6    3   8.4   4.6   25.9  78.7    -4.3   1127  5.7
 18000   -5.3  22.5   220    6    3   8.9   4.9   25.7  78.3    -4.6   1076  5.5
 17500   -3.9  25.0   220    6    3   9.2   5.0   25.6  78.1    -4.7   1020  5.2
 17000   -2.6  27.3   215    6    3   9.2   5.1   25.5  78.0    -4.8    965  4.9
 16500   -1.2  29.8   215    6    3   9.5   5.2   25.5  77.8    -4.9    909  4.6
 16000    0.2  32.4   210    6    3   9.5   5.2   25.4  77.8    -5.0    852  4.3
 15500    1.6  34.9   210    6    3   9.9   5.4   25.4  77.7    -5.1    795  4.0
 15000    3.1  37.6   210    6    3  10.0   5.5   25.4  77.8    -5.1    736  3.7
 14500    4.6  40.3   210    6    3   9.7   5.3   25.5  77.9    -5.1    677  3.4
 14000    5.9  42.6   210    6    3   9.4   5.2   25.4  77.8    -5.2    620  3.2
 13500    7.3  45.1   210    5    3   9.5   5.2   25.4  77.7    -5.3    564  2.9
 13000    8.9  48.0   210    5    3  10.4   5.7   25.5  77.9    -5.2    502  2.5
 12500   10.2  50.4   210    5    2   8.7   4.8   25.4  77.7    -5.4    448  2.3
 12000   11.5  52.7   215    4    2   8.4   4.6   25.2  77.4    -5.6    395  2.0
 11750   12.1  53.8   215    4    2   9.0   4.9   25.1  77.2    -5.7    368  1.9
 11500   12.9  55.2   215    4    2  10.6   5.8   25.1  77.2    -5.7    339  1.7
 11250   13.6  56.5   220    3    2   9.4   5.2   25.2  77.3    -5.7    309  1.6
 11000   14.2  57.6   220    3    2   7.9   4.4   25.1  77.1    -5.8    283  1.4
 10750   14.8  58.6   220    3    2   7.3   4.0   24.9  76.9    -6.0    259  1.3
 10500   15.4  59.7   220    3    1  10.3   5.6   24.8  76.6    -6.2    234  1.2
 10250   16.3  61.3   220    3    1  11.1   6.1   25.0  76.9    -6.0    200  1.0
 10000   16.9  62.4   215    3    1   7.3   4.0   24.9  76.8    -6.1    173  0.9
  9750   17.4  63.3   215    3    1   6.8   3.7   24.7  76.4    -6.4    151  0.8
  9500   17.9  64.2   215    3    1   7.4   4.1   24.4  76.0    -6.6    128  0.6
  9250   18.5  65.3   215    3    1   5.3   2.9   24.2  75.6    -6.8    105  0.5
  9000   18.6  65.5   225    3    1  -0.3  -0.2   23.7  74.6    -7.5     95  0.5
  8750   18.3  64.9   230    3    1  -3.1  -1.7   22.8  73.0    -8.5     94  0.5
  8500   18.1  64.6   235    3    2  -0.1  -0.0   21.9  71.4    -9.4     94  0.5
  8250   17.9  64.2   240    3    2  -8.8  -4.8   21.0  69.8   -10.4     93  0.5
  8000   16.3  61.3   240    3    2 -29.7 -16.3   18.8  65.8   -12.7    132  0.7
  7750   13.6  56.5   240    3    1 -38.2 -21.0   15.4  59.7   -16.3    208  1.1
  7500      M     M     M    M    M     M     M      M     M       M      M    M
  7250      M     M     M    M    M     M     M      M     M       M      M    M
  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 * * * * * *

           05/26/2018 at 0900 MDT          |       05/26/2018 at 1200 MDT
                                           |
CAPE...  +829.9    LI...        0.0        | CAPE...   +42.2    LI...       -0.2
CINH...   -70.3    K Index...  +2.2        | CINH...    -9.1    K Index...  +4.3
                                           |
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  245  16  8   1.4   0.8 | -63.5 -82.3  240  16  8   2.1   1.2
 45000 -61.4 -78.5  250  27 14   2.6   1.4 | -60.4 -76.7  250  24 12   1.3   0.7
 40000 -57.4 -71.3  260  31 16   6.2   3.4 | -58.2 -72.8  250  30 15   6.2   3.4
 38000 -53.2 -63.8  250  25 13   6.9   3.8 | -53.8 -64.8  245  28 15   7.4   4.0
 36000 -49.0 -56.2  240  20 10   6.9   3.8 | -49.4 -56.9  240  27 14   7.4   4.0
 34000 -45.0 -49.0  235  18  9   6.7   3.7 | -44.8 -48.6  235  24 12   7.7   4.2
 32000 -40.5 -40.9  235  16  8   6.7   3.7 | -39.6 -39.3  230  19 10   7.7   4.2
 30000 -35.9 -32.6  230  14  7   8.1   4.4 | -35.3 -31.5  225  17  8   7.1   3.9
 29000 -33.4 -28.1  225  13  7   8.1   4.4 | -33.2 -27.8  220  15  8   7.1   3.9
 28000 -31.0 -23.8  220  13  6   8.1   4.5 | -31.0 -23.8  215  14  7   7.3   4.0
 27000 -28.6 -19.5  220  12  6   8.2   4.5 | -28.7 -19.7  210  14  7   7.9   4.3
 26000 -26.1 -15.0  220  11  6   8.2   4.5 | -26.3 -15.3  210  14  7   7.9   4.3
 25000 -23.6 -10.5  215  11  6   8.2   4.5 | -23.9 -11.0  205  14  7   7.9   4.3
 24000 -21.1  -6.0  215  10  5   8.5   4.6 | -21.5  -6.7  200  14  7   8.4   4.6
 23000 -18.6  -1.5  210   9  5   8.5   4.6 | -19.0  -2.2  200  14  7   8.4   4.6
 22000 -16.1   3.0  210   8  4   8.5   4.7 | -16.4   2.5  195  13  7   8.5   4.6
 21000 -13.6   7.5  205   8  4   8.2   4.5 | -14.0   6.8  195  13  7   8.3   4.5
 20000 -11.2  11.8  200   8  4   8.2   4.5 | -11.5  11.3  200  12  6   8.3   4.5
 19500 -10.0  14.0  195   8  4   8.2   4.5 | -10.3  13.5  200  12  6   8.3   4.5
 19000  -8.8  16.2  195   8  4   8.5   4.6 |  -8.3  17.1  200  11  6   9.4   5.2
 18500  -6.9  19.6  195   8  4   8.6   4.7 |  -7.0  19.4  205  10  5   9.3   5.1
 18000  -5.6  21.9  195   8  4   9.1   5.0 |  -5.6  21.9  205   9  5   9.3   5.1
 17500  -4.2  24.4  195   8  4   9.4   5.1 |  -4.2  24.4  210   9  4   9.3   5.1
 17000  -2.8  27.0  195   7  4   9.4   5.2 |  -2.9  26.8  215   8  4   9.3   5.1
 16500  -1.4  29.5  195   7  4   9.5   5.2 |  -1.5  29.3  220   8  4   9.5   5.2
 16000   0.0  32.0  200   7  4   9.5   5.2 |  -0.1  31.8  225   7  4   9.5   5.2
 15500   1.5  34.7  200   7  4   9.5   5.2 |   1.3  34.3  225   7  4   9.8   5.4
 15000   2.8  37.0  205   7  3   9.5   5.2 |   2.8  37.0  225   7  3   9.9   5.4
 14500   4.2  39.6  205   6  3   9.3   5.1 |   4.2  39.6  225   7  3   9.8   5.4
 14000   5.5  41.9  210   6  3   9.2   5.0 |   5.7  42.3  225   6  3   9.7   5.3
 13500   6.9  44.4  210   5  3   9.4   5.1 |   7.1  44.8  225   6  3   9.8   5.4
 13000   8.3  46.9  210   5  2   9.9   5.4 |   8.6  47.5  225   6  3   9.9   5.4
 12500   9.6  49.3  210   4  2   8.6   4.7 |  10.0  50.0  225   6  3   9.1   5.0
 12000  10.9  51.6  215   4  2   8.8   4.9 |  11.4  52.5  220   6  3   9.2   5.1
 11750  11.6  52.9  215   4  2   9.0   4.9 |  12.1  53.8  220   6  3   9.7   5.3
 11500  12.3  54.1  215   4  2   9.8   5.4 |  12.8  55.0  220   6  3  10.9   6.0
 11250  13.0  55.4  215   4  2   8.8   4.8 |  13.6  56.5  220   6  3   9.6   5.3
 11000  13.5  56.3  215   4  2   7.8   4.3 |  14.3  57.7  220   6  3   8.6   4.7
 10750  14.1  57.4  215   4  2   7.5   4.1 |  14.9  58.8  215   6  3   8.1   4.4
 10500  14.7  58.5  220   4  2   9.6   5.3 |  15.6  60.1  215   6  3  11.0   6.1
 10250  15.5  59.9  220   3  2  10.2   5.6 |  16.5  61.7  215   5  3  12.0   6.6
 10000  16.1  61.0  225   3  2   8.2   4.5 |  17.3  63.1  215   5  3   9.1   5.0
  9750  16.7  62.1  225   3  2   8.2   4.5 |  18.0  64.4  215   5  3   9.7   5.3
  9500  17.4  63.3  230   3  2   9.3   5.1 |  18.7  65.7  210   5  3   8.7   4.8
  9250  18.0  64.4  235   3  2   5.0   2.8 |  19.4  66.9  210   5  3  12.2   6.7
  9000  18.1  64.6  240   3  2   3.7   2.0 |  20.4  68.7  210   5  3  12.4   6.8
  8750  18.6  65.5  240   3  1   6.8   3.7 |  21.1  70.0  210   5  3   9.3   5.1
  8500  19.0  66.2  245   3  1   6.5   3.5 |  21.9  71.4  205   5  3   9.8   5.3
  8250  19.4  66.9  245   3  1   4.4   2.4 |  22.6  72.7  205   5  3  11.1   6.1
  8000  19.5  67.1  245   2  1   6.7   3.7 |  23.6  74.5  205   5  3  18.4  10.1
  7750  20.3  68.5  240   2  1  17.2   9.4 |  25.3  77.5  205   5  2  25.5  14.0
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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

           05/26/2018 at 1500 MDT          |       05/26/2018 at 1800 MDT
                                           |
CAPE...    +7.2    LI...       +0.2        | CAPE...    +0.2    LI...       -0.4
CINH...     0.0    K Index...  +0.3        | CINH...    -1.7    K Index... +10.3
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -62.4 -80.3  185 145 74   2.2   1.2 | -61.9 -79.4  190 117 60   1.6   0.9
 45000 -59.4 -74.9  190 121 62   0.5   0.3 | -59.8 -75.6  195 102 53   0.4   0.2
 40000 -58.5 -73.3  205  79 41   5.6   3.1 | -59.0 -74.2  195 107 55   5.3   2.9
 38000 -54.1 -65.4  195 106 54   7.5   4.1 | -54.5 -66.1  190 135 69   7.6   4.2
 36000 -49.6 -57.3  190 133 69   7.5   4.1 | -49.9 -57.8  185 163 84   7.6   4.2
 34000 -44.8 -48.6  185 148 76   8.2   4.5 | -44.2 -47.6  185 175 90   8.9   4.9
 32000 -39.3 -38.7  185 155 80   8.2   4.5 | -38.9 -38.0  185 177 91   8.9   4.9
 30000 -35.1 -31.2  185 163 84   6.6   3.6 | -34.1 -29.4  180 182 94   7.6   4.2
 29000 -33.1 -27.6  185 167 86   6.7   3.6 | -31.8 -25.2  180 184 95   7.6   4.2
 28000 -31.1 -24.0  185 171 88   6.8   3.7 | -29.6 -21.3  180 187 96   7.6   4.2
 27000 -28.8 -19.8  180 173 89   7.9   4.3 | -27.6 -17.7  180 187 96   6.3   3.5
 26000 -26.4 -15.5  180 173 89   7.9   4.3 | -25.8 -14.4  180 187 96   6.3   3.5
 25000 -24.1 -11.4  180 174 90   7.8   4.3 | -23.9 -11.0  180 186 96   6.3   3.5
 24000 -21.6  -6.9  180 172 89   8.5   4.7 | -21.8  -7.2  180 186 96   7.8   4.3
 23000 -19.0  -2.2  180 170 87   8.6   4.7 | -19.4  -2.9  180 185 95   7.9   4.3
 22000 -16.5   2.3  185 167 86   8.5   4.7 | -17.1   1.2  180 185 95   7.8   4.3
 21000 -13.8   7.2  185 165 85   9.1   5.0 | -14.6   5.7  180 185 95   8.6   4.7
 20000 -10.5  13.1  185 162 84   9.1   5.0 | -11.4  11.5  180 186 96   8.6   4.7
 19500  -9.1  15.6  180 162 83   9.1   5.0 | -10.1  13.8  180 186 96   8.5   4.7
 19000  -7.7  18.1  180 162 84   9.2   5.0 |  -8.8  16.2  180 186 96   9.9   5.4
 18500  -6.4  20.5  180 164 85   9.2   5.0 |  -7.3  18.9  180 186 96   9.8   5.3
 18000  -5.0  23.0  180 166 86   9.2   5.0 |  -5.8  21.6  180 185 95   9.7   5.3
 17500  -3.6  25.5  180 168 87   9.2   5.1 |  -4.4  24.1  180 185 95   9.6   5.2
 17000  -2.3  27.9  180 170 87   9.2   5.1 |  -3.0  26.6  180 185 95   9.6   5.3
 16500  -0.9  30.4  180 172 89   9.1   5.0 |  -1.6  29.1  180 184 95   9.4   5.1
 16000   0.4  32.7  180 175 90   9.1   5.0 |  -0.2  31.6  180 184 95   9.4   5.1
 15500   1.8  35.2  180 178 92   9.3   5.1 |   1.2  34.2  180 184 95   9.5   5.2
 15000   3.2  37.8  180 181 93   9.3   5.1 |   2.7  36.9  180 184 95   9.5   5.2
 14500   4.6  40.3  180 183 94   9.3   5.1 |   4.1  39.4  180 184 95   9.5   5.2
 14000   6.0  42.8  180 185 95   9.3   5.1 |   5.5  41.9  180 184 95   9.3   5.1
 13500   7.3  45.1  180 188 97   9.3   5.1 |   6.9  44.4  180 184 95   9.3   5.1
 13000   8.8  47.8  180 188 97   9.7   5.3 |   8.4  47.1  180 185 95  10.4   5.7
 12500  10.2  50.4  180 188 97   9.0   5.0 |   9.8  49.6  180 185 95   9.2   5.0
 12000  11.5  52.7  180 187 96   9.3   5.1 |  11.1  52.0  180 185 95   8.8   4.8
 11750  12.2  54.0  180 186 96   9.7   5.3 |  11.8  53.2  180 185 95   9.4   5.2
 11500  13.0  55.4  180 185 95  10.6   5.8 |  12.5  54.5  180 185 95  10.4   5.7
 11250  13.8  56.8  180 184 95   9.9   5.4 |  13.3  55.9  180 185 95   9.9   5.4
 11000  14.4  57.9  180 183 94   8.9   4.9 |  14.0  57.2  180 185 95   9.1   5.0
 10750  15.1  59.2  180 183 94   8.4   4.6 |  14.7  58.5  180 185 95   8.5   4.7
 10500  15.8  60.4  180 182 94  10.2   5.6 |  15.3  59.5  180 186 95  10.2   5.6
 10250  16.6  61.9  180 182 93  11.4   6.3 |  16.2  61.2  180 185 95  11.4   6.2
 10000  17.4  63.3  180 181 93   9.7   5.3 |  17.0  62.6  180 185 95   9.8   5.4
  9750  18.1  64.6  180 180 93   9.6   5.3 |  17.7  63.9  180 185 95   9.4   5.2
  9500  18.8  65.8  180 180 93   9.2   5.0 |  18.4  65.1  180 185 95   9.3   5.1
  9250  19.5  67.1  180 179 92  11.1   6.1 |  19.1  66.4  180 185 95  10.2   5.6
  9000  20.4  68.7  180 178 92  11.4   6.3 |  19.9  67.8  180 185 95  10.3   5.6
  8750  21.2  70.2  180 177 91   9.9   5.4 |  20.6  69.1  180 185 95   9.4   5.1
  8500  22.0  71.6  180 177 91   9.9   5.4 |  21.3  70.3  180 184 95   9.5   5.2
  8250  22.7  72.9  180 176 91  11.4   6.3 |  22.0  71.6  180 184 95   9.9   5.4
  8000  23.8  74.8  180 176 90  18.1   9.9 |  22.8  73.0  180 184 95  10.5   5.7
  7750  25.3  77.5  180 175 90  23.8  13.1 |  23.5  74.3  180 184 95  10.1   5.6
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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).  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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