Soaring Guidance
Issued by NWS Pueblo, CO

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378
UXUS97 KPUB 271307
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0707 MDT Saturday, May 27, 2017

This forecast is for Saturday, May 27, 2017:

If the trigger temperature of 61.6 F/16.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9825 ft MSL (2199 ft AGL)

Forecast maximum temperature................... 56.0 F/13.8 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1100 MDT
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................. 9161 ft MSL (1535 ft AGL)
Thermal soaring outlook for Sunday 05/28....... Good

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

Remarks...

Sunrise/Sunset.................... 05:37:37 / 20:15:23 MDT
Total possible sunshine........... 14 hr 37 min 46 sec (877 min 46 sec)
Altitude of sun at 12:56:30 MDT... 72.42 degrees

Upper air data from numerical model forecast valid on 05/27/2017 at 0600 MDT

Freezing level.................. 13130 ft MSL (5504 ft AGL)
Convective condensation level... 17431 ft MSL (9805 ft AGL)
Lifted condensation level....... 15218 ft MSL (7592 ft AGL)
Lifted index.................... +3.2
K index......................... -4.3

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  -57.0 -70.6   255   16    8  -0.1  -0.0      M     M       M      M    M
 45000  -57.1 -70.8   245   22   12  -0.2  -0.1      M     M       M      M    M
 40000  -57.4 -71.3   250   28   15  -0.2  -0.1      M     M       M      M    M
 38000  -55.7 -68.3   250   28   14   4.4   2.4      M     M       M      M    M
 36000  -52.7 -62.9   245   26   14   4.4   2.4      M     M       M      M    M
 34000  -49.2 -56.6   240   25   13   7.5   4.1      M     M       M      M    M
 32000  -44.7 -48.5   240   23   12   7.5   4.1      M     M       M      M    M
 30000  -40.1 -40.2   240   22   12   8.0   4.4   28.2  82.7    11.5      M    M
 29000  -37.7 -35.9   240   22   11   8.0   4.4   27.5  81.4    11.1      M    M
 28000  -35.3 -31.5   240   22   11   8.0   4.4   26.9  80.4    10.7      M    M
 27000  -33.0 -27.4   240   22   11   7.3   4.0   26.2  79.2    10.3      M    M
 26000  -30.8 -23.4   245   21   11   7.4   4.1   25.2  77.4     9.7      M    M
 25000  -28.5 -19.3   245   21   11   7.4   4.1   24.4  75.9     9.1      M    M
 24000  -26.3 -15.3   245   21   11   7.9   4.4   23.7  74.6     8.6      M    M
 23000  -23.9 -11.0   240   19   10   8.0   4.4   23.0  73.4     8.1      M    M
 22000  -20.9  -5.6   230   18    9   8.0   4.4   22.3  72.1     7.6      M    M
 21000  -18.6  -1.5   230   17    9   7.6   4.2   21.6  70.8     7.1      M    M
 20000  -16.3   2.7   235   16    8   7.6   4.2   20.8  69.4     6.5      M    M
 19500  -15.2   4.6   235   16    8   7.6   4.2   20.4  68.8     6.2      M    M
 19000  -14.0   6.8   240   16    8   7.8   4.3   20.1  68.2     6.0      M    M
 18500  -12.8   9.0   245   16    8   8.4   4.6   19.9  67.8     5.8      M    M
 18000  -11.6  11.1   250   16    8   8.4   4.6   19.6  67.3     5.6      M    M
 17500  -10.4  13.3   250   16    8   7.2   3.9   19.3  66.8     5.4      M    M
 17000   -9.3  15.3   255   17    9   7.0   3.8   18.9  66.0     4.9      M    M
 16500   -8.3  17.1   260   18    9   6.7   3.7   18.4  65.1     4.5      M    M
 16000   -7.4  18.7   260   18    9   6.3   3.5   17.8  64.1     4.0      M    M
 15500   -6.5  20.3   265   17    9   6.4   3.5   17.3  63.2     3.5      M    M
 15000   -5.3  22.5   265   17    9   9.6   5.3   17.0  62.7     3.2      M    M
 14500   -4.0  24.8   265   16    8   9.3   5.1   17.0  62.5     3.1      M    M
 14000   -2.6  27.3   270   16    8   9.5   5.2   16.9  62.4     3.0      M    M
 13500   -1.2  29.8   270   15    8   9.5   5.2   16.9  62.4     3.0      M    M
 13000    0.3  32.5   270   15    8  12.8   7.0   16.9  62.5     3.1      M    M
 12500    1.9  35.4   270   15    8   7.6   4.2   17.1  62.8     3.2      M    M
 12000    3.2  37.8   270   15    8   8.8   4.8   16.9  62.4     3.0      M    M
 11750    3.9  39.0   270   14    7   9.7   5.3   16.9  62.3     3.0      M    M
 11500    4.6  40.3   270   13    7   8.8   4.8   16.8  62.3     3.0      M    M
 11250    5.2  41.4   275   12    6   9.3   5.1   16.7  62.1     2.9      M    M
 11000    5.9  42.6   275   11    6   6.0   3.3   16.7  62.0     2.8      M    M
 10750    6.1  43.0   275   10    5   2.9   1.6   16.2  61.1     2.3      M    M
 10500    6.3  43.3   275    9    5   3.3   1.8   15.7  60.2     1.9      M    M
 10250    6.6  43.9   280    8    4   6.7   3.7   15.3  59.5     1.4      M    M
 10000    7.1  44.8   280    7    3   1.3   0.7   15.0  59.0     1.2      M    M
  9750    6.7  44.1   290    6    3  -5.7  -3.1   13.9  57.0     0.1      M    M
  9500    6.4  43.5   295    6    3  -3.9  -2.1   12.8  55.1    -1.0    228  1.2
  9250    6.0  42.8   305    6    3  -3.9  -2.1   11.8  53.2    -2.1    232  1.2
  9000    5.6  42.1   310    5    3  -5.6  -3.1   10.7  51.3    -3.3    237  1.2
  8750    5.0  41.0   315    6    3  -7.2  -4.0    9.4  49.0    -4.6    247  1.3
  8500    4.4  39.9   320    6    3  -7.2  -4.0    8.2  46.7    -6.0    258  1.3
  8250    3.8  38.8   325    7    4  -5.1  -2.8    6.9  44.5    -7.3    268  1.4
  8000    3.7  38.7   325    7    4   4.9   2.7    6.1  43.0    -8.2    264  1.3
  7750    4.4  39.9   325    6    3  14.8   8.1    6.2  43.2    -8.2    234  1.2
  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 * * * * * *

           05/27/2017 at 0900 MDT          |       05/27/2017 at 1200 MDT
                                           |
CAPE...   +98.1    LI...       -0.6        | CAPE...  +501.1    LI...       -2.8
CINH...   -76.9    K Index...  +4.0        | CINH...     0.0    K Index... +23.4
                                           |
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 -56.5 -69.7  250  16  8   0.3   0.1 | -56.3 -69.3  255  16  8   1.1   0.6
 45000 -56.3 -69.3  250  25 13  -0.7  -0.4 | -54.9 -66.8  260  26 14  -1.1  -0.6
 40000 -57.3 -71.1  245  30 15  -0.7  -0.4 | -56.5 -69.7  250  31 16  -1.0  -0.6
 38000 -55.6 -68.1  245  31 16   4.7   2.6 | -54.7 -66.5  245  32 17   4.4   2.4
 36000 -52.5 -62.5  245  30 16   4.7   2.6 | -52.0 -61.6  245  33 17   4.4   2.4
 34000 -49.0 -56.2  240  30 15   7.2   4.0 | -48.8 -55.8  240  33 17   7.0   3.8
 32000 -44.7 -48.5  240  29 15   7.2   4.0 | -44.6 -48.3  240  33 17   7.0   3.8
 30000 -40.2 -40.4  240  27 14   7.8   4.3 | -40.3 -40.5  245  32 17   7.2   4.0
 29000 -37.9 -36.2  240  26 14   7.8   4.3 | -38.2 -36.8  245  32 16   7.2   4.0
 28000 -35.6 -32.1  245  26 13   7.8   4.3 | -36.0 -32.8  245  31 16   7.2   4.0
 27000 -33.3 -27.9  245  25 13   7.4   4.0 | -33.8 -28.8  245  30 15   7.1   3.9
 26000 -31.1 -24.0  245  24 12   7.4   4.1 | -31.7 -25.1  245  29 15   7.2   3.9
 25000 -28.8 -19.8  245  23 12   7.4   4.1 | -29.5 -21.1  245  28 14   7.2   3.9
 24000 -26.6 -15.9  245  22 11   6.9   3.8 | -27.4 -17.3  245  27 14   6.9   3.8
 23000 -24.6 -12.3  250  21 11   6.7   3.7 | -25.4 -13.7  245  26 13   6.7   3.7
 22000 -22.6  -8.7  250  20 11   6.7   3.7 | -22.9  -9.2  250  25 13   6.8   3.7
 21000 -20.0  -4.0  255  20 10   7.5   4.1 | -20.8  -5.4  250  24 12   7.7   4.2
 20000 -17.8  -0.0  255  20 10   7.6   4.2 | -18.5  -1.3  250  22 11   7.8   4.3
 19500 -16.6   2.1  255  20 10   7.6   4.2 | -17.4   0.7  250  22 11   7.8   4.3
 19000 -15.5   4.1  260  20 10   7.8   4.3 | -16.2   2.8  255  21 11   7.9   4.3
 18500 -14.2   6.4  260  20 10   9.2   5.0 | -15.0   5.0  255  20 10   8.6   4.7
 18000 -12.8   9.0  260  20 10   9.2   5.1 | -13.8   7.2  255  19 10   8.6   4.7
 17500 -11.5  11.3  265  20 10   7.6   4.2 | -12.5   9.5  260  17  9   8.1   4.5
 17000 -10.5  13.1  265  20 10   7.3   4.0 | -11.4  11.5  260  16  8   8.0   4.4
 16500  -9.4  15.1  265  20 10   7.2   4.0 | -10.2  13.6  265  15  8   7.9   4.4
 16000  -8.4  16.9  265  19 10   7.0   3.8 |  -9.1  15.6  265  14  7   7.7   4.2
 15500  -7.3  18.9  265  18  9   7.0   3.9 |  -8.0  17.6  265  13  7   7.8   4.3
 15000  -6.3  20.7  270  16  8   7.8   4.3 |  -6.9  19.6  265  12  6   7.3   4.0
 14500  -5.2  22.6  270  15  8   7.8   4.3 |  -5.8  21.6  265  11  6   7.5   4.1
 14000  -4.0  24.8  270  13  7   8.8   4.8 |  -4.8  23.4  265   9  5   6.6   3.6
 13500  -2.8  27.0  275  11  6   8.9   4.9 |  -3.9  25.0  265   8  4   6.5   3.6
 13000  -1.5  29.3  280  10  5  10.4   5.7 |  -2.9  26.8  265   6  3   7.5   4.1
 12500  -0.1  31.8  285   8  4   7.8   4.3 |  -2.0  28.4  275   5  2   5.2   2.8
 12000   1.1  34.0  290   7  4   7.2   3.9 |  -1.2  29.8  295   4  2   5.3   2.9
 11750   1.6  34.9  290   7  3   6.3   3.5 |  -0.8  30.6  305   3  2   5.0   2.7
 11500   2.1  35.8  295   6  3   7.6   4.1 |  -0.5  31.1  315   3  2   6.2   3.4
 11250   2.8  37.0  300   6  3   8.7   4.8 |   0.0  32.0  335   3  2   7.5   4.1
 11000   3.4  38.1  300   6  3   6.5   3.6 |   0.6  33.1  355   3  2   7.4   4.1
 10750   3.8  38.8  305   6  3   4.9   2.7 |   1.1  34.0  005   4  2   7.6   4.2
 10500   4.2  39.6  310   5  3   5.5   3.0 |   1.6  34.9  015   5  2   7.8   4.3
 10250   4.6  40.3  310   5  2   8.2   4.5 |   2.3  36.1  020   5  3  11.2   6.1
 10000   5.3  41.5  315   5  2   6.7   3.7 |   3.2  37.8  025   6  3  11.4   6.2
  9750   5.6  42.1  315   4  2   3.9   2.1 |   3.9  39.0  025   6  3   9.3   5.1
  9500   5.9  42.6  320   4  2   3.9   2.1 |   4.6  40.3  025   6  3   9.7   5.3
  9250   6.2  43.2  325   4  2   6.7   3.7 |   5.3  41.5  025   6  3  10.3   5.7
  9000   6.7  44.1  325   4  2   6.7   3.7 |   6.1  43.0  030   6  3  10.7   5.9
  8750   7.0  44.6  325   4  2   3.9   2.1 |   6.9  44.4  030   6  3  10.2   5.6
  8500   7.2  45.0  330   5  2   4.3   2.3 |   7.7  45.9  030   6  3  10.1   5.5
  8250   7.5  45.5  330   5  3   6.4   3.5 |   8.4  47.1  030   6  3  11.2   6.1
  8000   8.1  46.6  335   5  2  14.6   8.0 |   9.5  49.1  030   6  3  19.3  10.6
  7750   9.5  49.1  340   4  2  21.3  11.7 |  11.3  52.3  030   6  3  29.1  16.0
  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

           05/27/2017 at 1500 MDT          |       05/27/2017 at 1800 MDT
                                           |
CAPE...  +284.2    LI...       +0.8        | CAPE...   +40.5    LI...       -0.1
CINH...   -15.6    K Index... +23.8        | CINH...    -6.6    K Index... +20.6
                                           |
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 -56.4 -69.5  255  17  9   2.3   1.3 | -56.9 -70.4  260  16  8   1.6   0.9
 45000 -53.4 -64.1  265  25 13  -1.4  -0.8 | -54.6 -66.3  265  22 12   0.1   0.1
 40000 -55.4 -67.7  255  34 18  -1.2  -0.7 | -54.4 -65.9  260  30 15   0.2   0.1
 38000 -54.3 -65.7  250  36 18   2.9   1.6 | -53.3 -63.9  255  33 17   2.4   1.3
 36000 -52.5 -62.5  250  36 19   2.9   1.6 | -51.8 -61.2  250  36 18   2.4   1.3
 34000 -50.0 -58.0  250  35 18   6.2   3.4 | -49.6 -57.3  245  37 19   6.1   3.4
 32000 -46.3 -51.3  255  32 16   6.2   3.4 | -45.9 -50.6  235  35 18   6.1   3.3
 30000 -42.1 -43.8  255  29 15   8.0   4.4 | -41.6 -42.9  225  34 17   8.7   4.8
 29000 -39.8 -39.6  255  27 14   8.0   4.4 | -39.0 -38.2  225  32 17   8.7   4.8
 28000 -37.4 -35.3  255  25 13   8.0   4.4 | -36.4 -33.5  220  31 16   8.8   4.8
 27000 -34.9 -30.8  250  24 12   9.5   5.2 | -33.9 -29.0  220  30 16   8.2   4.5
 26000 -32.1 -25.8  250  23 12   9.4   5.1 | -31.4 -24.5  220  29 15   8.3   4.6
 25000 -29.3 -20.7  250  21 11   9.4   5.1 | -28.9 -20.0  220  28 14   8.3   4.6
 24000 -26.5 -15.7  245  20 10   8.9   4.9 | -26.5 -15.7  225  27 14   6.9   3.8
 23000 -23.3  -9.9  245  17  9   8.8   4.8 | -24.1 -11.4  230  25 13   6.3   3.5
 22000 -20.6  -5.1  245  15  8   8.8   4.8 | -22.3  -8.1  240  24 12   6.3   3.5
 21000 -18.2  -0.8  240  12  6   7.4   4.1 | -20.3  -4.5  245  23 12   7.1   3.9
 20000 -16.1   3.0  240  10  5   7.4   4.1 | -18.2  -0.8  250  22 11   7.1   3.9
 19500 -15.0   5.0  240   9  5   7.4   4.1 | -17.1   1.2  250  21 11   7.1   3.9
 19000 -13.9   7.0  240   8  4   7.2   3.9 | -16.1   3.0  255  20 11   7.2   3.9
 18500 -13.0   8.6  240   8  4   5.9   3.3 | -15.0   5.0  255  20 10   7.3   4.0
 18000 -12.1  10.2  240   7  4   6.0   3.3 | -13.9   7.0  260  20 10   7.3   4.0
 17500 -11.2  11.8  240   6  3   6.3   3.4 | -12.9   8.8  265  19 10   6.9   3.8
 17000 -10.3  13.5  240   5  3   6.3   3.5 | -11.9  10.6  270  18  9   6.9   3.8
 16500  -9.4  15.1  240   4  2   6.0   3.3 | -10.9  12.4  275  18  9   7.1   3.9
 16000  -8.6  16.5  245   4  2   5.4   3.0 |  -9.8  14.4  280  16  8   7.7   4.2
 15500  -7.8  18.0  255   3  2   5.4   3.0 |  -8.7  16.3  285  15  8   7.7   4.2
 15000  -7.0  19.4  270   2  1   5.6   3.1 |  -7.6  18.3  290  15  8   7.8   4.3
 14500  -6.2  20.8  295   2  1   5.7   3.1 |  -6.4  20.5  295  14  7   7.9   4.3
 14000  -5.4  22.3  315   2  1   5.3   2.9 |  -5.4  22.3  295  14  7   6.3   3.5
 13500  -4.6  23.7  340   3  1   5.3   2.9 |  -4.5  23.9  300  13  7   6.4   3.5
 13000  -3.8  25.2  355   4  2   5.4   2.9 |  -3.6  25.5  305  12  6   4.6   2.5
 12500  -3.1  26.4  005   4  2   4.4   2.4 |  -3.0  26.6  315  12  6   4.1   2.2
 12000  -2.5  27.5  010   5  2   4.5   2.5 |  -2.5  27.5  320  12  6   3.1   1.7
 11750  -2.2  28.0  010   5  3   4.6   2.5 |  -2.3  27.9  320  11  6   2.8   1.5
 11500  -1.8  28.8  010   5  3   4.8   2.6 |  -2.1  28.2  325  11  6   2.1   1.1
 11250  -1.5  29.3  015   6  3   5.1   2.8 |  -2.0  28.4  330  11  6   1.0   0.6
 11000  -1.1  30.0  015   6  3   4.3   2.4 |  -1.9  28.6  330  11  6   3.0   1.7
 10750  -0.9  30.4  015   6  3   3.9   2.1 |  -1.6  29.1  335  11  5   4.6   2.5
 10500  -0.6  30.9  010   7  3   3.7   2.0 |  -1.3  29.7  340  11  5   3.7   2.0
 10250  -0.3  31.5  010   7  4   5.4   2.9 |  -1.0  30.2  345  11  5   5.6   3.1
 10000   0.2  32.4  010   7  4   7.9   4.3 |  -0.6  30.9  350  11  5   5.5   3.0
  9750   0.8  33.4  010   8  4   8.0   4.4 |  -0.3  31.5  350  11  5   4.0   2.2
  9500   1.4  34.5  010   8  4   8.4   4.6 |   0.0  32.0  355  11  6   3.9   2.1
  9250   1.9  35.4  010   8  4   6.7   3.7 |   0.3  32.5  360  11  6   5.8   3.2
  9000   2.4  36.3  010   8  4   8.2   4.5 |   0.9  33.6  360  10  5   8.9   4.9
  8750   3.1  37.6  005   9  4  11.0   6.0 |   1.5  34.7  360  10  5   9.2   5.0
  8500   3.9  39.0  005   9  4  10.5   5.8 |   2.2  36.0  005   9  5   9.1   5.0
  8250   4.6  40.3  005   9  5   9.7   5.3 |   2.8  37.0  005   9  5   9.5   5.2
  8000   5.3  41.5  360   8  4  10.8   5.9 |   3.6  38.5  005   8  4  12.2   6.7
  7750   6.2  43.2  360   7  3  15.9   8.7 |   4.6  40.3  005   7  4  15.5   8.5
  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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