Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 261345
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0645 MST Sunday, February 26, 2017

This forecast is for Sunday, February 26, 2017:

If the trigger temperature of 24.3 F/-4.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 765 ft/min (3.9 m/s)
   Maximum height of thermals.................. 16207 ft MSL (8647 ft AGL)

Forecast maximum temperature................... 33.0 F/1.0 C
Time of trigger temperature.................... 0930 MST
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................. 13037 ft MSL (5476 ft AGL)
Thermal soaring outlook for Monday 02/27....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:35:16 / 17:48:53 MST
Total possible sunshine........... 11 hr 13 min 37 sec (673 min 37 sec)
Altitude of sun at 12:12:04 MST... 42.51 degrees

Upper air data from numerical model forecast valid on 02/26/2017 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 16596 ft MSL (9036 ft AGL)
Lifted condensation level....... 16611 ft MSL (9051 ft AGL)
Lifted index.................... +7.7
K index......................... -8.8

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  -55.9 -68.6   265   28   14   1.4   0.8      M     M       M      M    M
 45000  -53.7 -64.7   260   35   18   1.4   0.8      M     M       M      M    M
 40000  -51.9 -61.4   265   36   19   1.1   0.6      M     M       M      M    M
 38000  -51.3 -60.3   265   37   19   0.9   0.5      M     M       M      M    M
 36000  -51.1 -60.0   265   34   18   0.2   0.1      M     M       M      M    M
 34000  -51.0 -59.8   270   32   16   0.2   0.1      M     M       M      M    M
 32000  -50.5 -58.9   270   27   14   1.3   0.7      M     M       M      M    M
 30000  -49.6 -57.3   275   20   10   1.3   0.7      M     M       M      M    M
 29000  -48.8 -55.8   280   17    9   5.4   2.9   18.0  64.4    13.4      M    M
 28000  -47.3 -53.1   285   14    7   5.1   2.8   16.1  60.9    12.1      M    M
 27000  -45.8 -50.4   290   11    6   5.1   2.8   14.3  57.7    10.9      M    M
 26000  -44.3 -47.7   305    9    4   5.7   3.1   12.7  54.8     9.7      M    M
 25000  -42.2 -44.0   305    8    4   7.0   3.8   11.5  52.7     8.9      M    M
 24000  -40.1 -40.2   305    7    4   7.0   3.8   10.5  50.9     8.1      M    M
 23000  -38.0 -36.4   305    7    4   6.7   3.7    9.6  49.3     7.5      M    M
 22000  -36.3 -33.3   300    7    3   5.6   3.1    8.1  46.6     6.3      M    M
 21000  -34.6 -30.3   295    6    3   5.6   3.1    6.6  43.9     5.2      M    M
 20000  -32.9 -27.2   295    7    3   5.6   3.1    5.3  41.5     4.1      M    M
 19500  -32.1 -25.8   290    8    4   5.6   3.1    4.5  40.1     3.4      M    M
 19000  -31.3 -24.3   290    9    5   5.6   3.1    3.7  38.7     2.8      M    M
 18500  -30.5 -22.9   290   10    5   5.6   3.0    3.0  37.5     2.2      M    M
 18000  -29.6 -21.3   290   11    6   5.4   3.0    2.4  36.3     1.6      M    M
 17500  -28.2 -18.8   285   14    7   7.4   4.1    1.6  34.9     0.9      M    M
 17000  -27.1 -16.8   285   16    8   7.4   4.1    1.2  34.2     0.5      M    M
 16500  -26.0 -14.8   280   18    9   7.2   4.0    0.8  33.4     0.2      M    M
 16000  -24.9 -12.8   280   20   10   7.3   4.0    0.4  32.7    -0.2    737  3.7
 15500  -23.9 -11.0   280   22   11   6.2   3.4   -0.1  31.9    -0.7    691  3.5
 15000  -23.0  -9.4   280   22   12   5.9   3.3   -0.7  30.7    -1.3    650  3.3
 14500  -22.1  -7.8   275   23   12   6.7   3.7   -1.3  29.6    -1.8    609  3.1
 14000  -21.0  -5.8   280   23   12   7.3   4.0   -1.7  28.9    -2.2    561  2.9
 13500  -19.9  -3.8   280   23   12   7.0   3.9   -2.1  28.2    -2.6    514  2.6
 13000  -18.9  -2.0   280   23   12   6.7   3.7   -2.6  27.3    -3.1    469  2.4
 12500  -17.9  -0.2   285   22   11   5.7   3.1   -3.1  26.5    -3.5    424  2.2
 12000  -17.1   1.2   285   20   10   6.7   3.7   -3.7  25.3    -4.2    384  2.0
 11750  -16.6   2.1   285   18   10   6.0   3.3   -4.0  24.9    -4.4    362  1.8
 11500  -16.1   3.0   285   17    9   7.5   4.1   -4.2  24.4    -4.7    341  1.7
 11250  -15.5   4.1   285   16    8   8.5   4.7   -4.3  24.2    -4.8    314  1.6
 11000  -14.9   5.2   290   15    8   7.8   4.3   -4.5  23.9    -5.0    289  1.5
 10750  -14.3   6.3   290   13    7   8.1   4.5   -4.6  23.7    -5.1    264  1.3
 10500  -13.7   7.3   290   12    6   6.7   3.7   -4.8  23.4    -5.3    240  1.2
 10250  -13.2   8.2   290   10    5   7.0   3.8   -5.0  22.9    -5.6    218  1.1
 10000  -12.6   9.3   295    9    5   9.3   5.1   -5.1  22.7    -5.7    192  1.0
  9750  -11.9  10.6   295    8    4   9.0   4.9   -5.2  22.7    -5.7    164  0.8
  9500  -11.3  11.7   300    6    3   7.3   4.0   -5.3  22.5    -5.9    138  0.7
  9250  -10.8  12.6   300    5    3   6.3   3.4   -5.5  22.0    -6.1    116  0.6
  9000  -10.3  13.5   305    4    2   7.1   3.9   -5.8  21.6    -6.4     94  0.5
  8750   -9.9  14.2   310    3    2   3.6   2.0   -6.0  21.1    -6.7     73  0.4
  8500   -9.8  14.4   310    3    1  -0.6  -0.3   -6.7  19.9    -7.4     64  0.3
  8250   -9.8  14.4   315    2    1   0.4   0.2   -7.5  18.5    -8.1     57  0.3
  8000   -9.8  14.4   320    2    1  -0.8  -0.4   -8.2  17.3    -8.9     49  0.2
  7750  -10.3  13.5   315    2    1 -15.4  -8.4   -9.4  15.1   -10.1     56  0.3
  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 * * * * * *

           02/26/2017 at 0800 MST          |       02/26/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +3.7        | CAPE...     0.0    LI...       +4.4
CINH...     0.0    K Index... -11.6        | CINH...    -0.5    K Index... -19.3
                                           |
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 -55.9 -68.6  265  28 14   1.4   0.7 | -55.2 -67.4  255  29 15   1.1   0.6
 45000 -53.8 -64.8  260  34 17   1.4   0.7 | -53.5 -64.3  255  32 16   1.1   0.6
 40000 -52.1 -61.8  260  34 18   1.0   0.6 | -53.5 -64.3  255  30 15  -0.2  -0.1
 38000 -51.5 -60.7  260  34 17   0.9   0.5 | -53.6 -64.5  255  29 15  -0.0  -0.0
 36000 -51.3 -60.3  260  30 15   0.3   0.2 | -53.3 -63.9  260  25 13   0.6   0.3
 34000 -51.1 -60.0  265  26 13   0.3   0.2 | -52.8 -63.0  270  20 10   0.6   0.4
 32000 -50.5 -58.9  270  20 10   1.3   0.7 | -51.8 -61.2  280  15  8   2.3   1.3
 30000 -49.7 -57.5  280  14  7   1.3   0.7 | -50.4 -58.7  305  11  6   2.4   1.3
 29000 -48.9 -56.0  285  11  6   5.4   2.9 | -49.2 -56.6  315  10  5   6.8   3.7
 28000 -47.4 -53.3  290   9  5   5.1   2.8 | -47.2 -53.0  320  10  5   6.7   3.7
 27000 -45.9 -50.6  295   8  4   5.1   2.8 | -45.2 -49.4  325  10  5   6.7   3.7
 26000 -44.4 -47.9  305   6  3   5.8   3.2 | -43.2 -45.8  330  10  5   6.8   3.7
 25000 -42.2 -44.0  315   5  3   7.3   4.0 | -41.1 -42.0  330   8  4   7.0   3.8
 24000 -40.0 -40.0  320   5  3   7.3   4.0 | -39.0 -38.2  330   7  4   7.0   3.8
 23000 -37.8 -36.0  330   5  2   6.9   3.8 | -36.9 -34.4  330   6  3   7.2   4.0
 22000 -36.1 -33.0  315   4  2   5.8   3.2 | -34.6 -30.3  330   5  3   7.5   4.1
 21000 -34.3 -29.7  295   4  2   5.8   3.2 | -31.8 -25.2  325   4  2   7.4   4.1
 20000 -32.2 -26.0  275   4  2   5.3   2.9 | -30.1 -22.2  310   4  2   3.9   2.1
 19500 -31.5 -24.7  270   4  2   5.3   2.9 | -29.5 -21.1  295   4  2   3.9   2.1
 19000 -30.7 -23.3  265   4  2   5.3   2.9 | -28.9 -20.0  280   4  2   3.9   2.1
 18500 -29.9 -21.8  265   4  2   5.4   2.9 | -28.3 -18.9  270   5  2   3.9   2.1
 18000 -29.1 -20.4  260   4  2   5.9   3.3 | -27.7 -17.9  260   5  3   3.9   2.1
 17500 -28.0 -18.4  270   4  2   7.5   4.1 | -27.2 -17.0  255   6  3   3.9   2.1
 17000 -26.9 -16.4  280   5  3   7.7   4.2 | -26.6 -15.9  245   6  3   3.6   2.0
 16500 -25.9 -14.6  285   6  3   5.8   3.2 | -25.9 -14.6  245   6  3   6.1   3.4
 16000 -25.0 -13.0  285   8  4   5.9   3.3 | -25.0 -13.0  250   7  3   5.8   3.2
 15500 -24.1 -11.4  285   9  5   6.0   3.3 | -24.1 -11.4  255   7  4   7.0   3.8
 15000 -23.2  -9.8  285  11  6   6.0   3.3 | -23.0  -9.4  260   8  4   7.2   3.9
 14500 -22.3  -8.1  285  13  7   6.3   3.5 | -21.9  -7.4  270   9  5   7.1   3.9
 14000 -21.4  -6.5  285  14  7   6.5   3.6 | -20.8  -5.4  275  10  5   7.1   3.9
 13500 -20.4  -4.7  285  16  8   6.5   3.5 | -19.8  -3.6  280  10  5   7.3   4.0
 13000 -19.5  -3.1  285  16  8   6.5   3.6 | -18.7  -1.7  285  11  6   7.3   4.0
 12500 -18.5  -1.3  285  17  9   7.9   4.3 | -17.5   0.5  285  12  6   4.1   2.3
 12000 -17.6   0.3  290  15  8   4.1   2.3 | -17.0   1.4  280  12  6   6.6   3.6
 11750 -17.2   1.0  290  15  8   4.2   2.3 | -16.6   2.1  280  12  6   5.3   2.9
 11500 -16.9   1.6  290  14  7   6.3   3.5 | -16.2   2.8  275  11  6   7.1   3.9
 11250 -16.3   2.7  290  13  7   7.4   4.1 | -15.6   3.9  270  10  5   8.1   4.5
 11000 -15.8   3.6  285  12  6   5.9   3.2 | -15.0   5.0  265   9  5   7.5   4.1
 10750 -15.4   4.3  285  11  6   6.3   3.5 | -14.5   5.9  260   8  4   7.8   4.3
 10500 -14.9   5.2  285  10  5   7.5   4.1 | -13.9   7.0  250   8  4   6.4   3.5
 10250 -14.3   6.3  280  10  5   9.0   5.0 | -13.5   7.7  240   7  4   6.6   3.6
 10000 -13.6   7.5  280   9  5   9.6   5.3 | -12.9   8.8  235   6  3   8.6   4.7
  9750 -12.8   9.0  275   8  4   9.6   5.3 | -12.2  10.0  230   6  3   8.6   4.7
  9500 -12.2  10.0  275   7  4   8.8   4.8 | -11.6  11.1  225   5  3   8.0   4.4
  9250 -11.5  11.3  270   7  3   8.4   4.6 | -11.0  12.2  215   5  2   8.0   4.4
  9000 -10.8  12.6  270   6  3  10.3   5.6 | -10.4  13.3  205   4  2   9.6   5.2
  8750 -10.1  13.8  265   5  3   7.7   4.2 |  -9.7  14.5  200   4  2  10.2   5.6
  8500  -9.7  14.5  265   5  2   3.7   2.0 |  -8.9  16.0  195   4  2   9.8   5.4
  8250  -9.4  15.1  265   4  2   4.9   2.7 |  -8.2  17.2  190   4  2   9.7   5.3
  8000  -9.1  15.6  265   4  2   3.9   2.2 |  -7.5  18.5  185   4  2   9.7   5.3
  7750  -9.1  15.6  265   3  1  -7.2  -3.9 |  -6.7  19.9  180   4  2  13.3   7.3
  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

           02/26/2017 at 1400 MST          |       02/26/2017 at 1700 MST
                                           |
CAPE...   +48.6    LI...       +4.8        | CAPE...   +20.0    LI...       +5.7
CINH...    -2.4    K Index... -13.1        | CINH...   -10.4    K Index... -15.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -55.1 -67.2  205  74 38   0.8   0.4 | -56.5 -69.7  210  65 34   1.1   0.6
 45000 -53.9 -65.0  210  65 33   0.8   0.4 | -54.9 -66.8  210  63 33   1.1   0.6
 40000 -56.0 -68.8  220  48 25  -1.9  -1.0 | -56.1 -69.0  230  44 23  -1.3  -0.7
 38000 -57.1 -70.8  225  41 21  -0.2  -0.1 | -56.9 -70.4  245  38 19  -0.8  -0.5
 36000 -56.2 -69.2  300  28 15   1.4   0.7 | -57.2 -71.0  280  33 17  -0.6  -0.3
 34000 -55.4 -67.7  340  60 31   1.3   0.7 | -57.6 -71.7  315  41 21  -0.5  -0.3
 32000 -53.5 -64.3  350 109 56   4.2   2.3 | -55.1 -67.2  335  57 29   6.4   3.5
 30000 -51.0 -59.8  355 166 85   4.3   2.4 | -51.3 -60.3  340  75 39   6.4   3.5
 29000 -49.3 -56.7  355 188 97   7.5   4.1 | -49.1 -56.4  345  83 43   7.7   4.2
 28000 -47.1 -52.8  355 200 103   7.4   4.0 | -46.8 -52.2  345  90 46   7.8   4.3
 27000 -44.9 -48.8  360 211 109   7.4   4.0 | -44.4 -47.9  350  96 50   7.8   4.3
 26000 -42.7 -44.9  360 223 115   7.4   4.0 | -42.1 -43.8  350 103 53   7.9   4.3
 25000 -39.9 -39.8  360 210 108   7.4   4.0 | -39.7 -39.5  350 110 56   7.9   4.3
 24000 -37.7 -35.9  360 200 103   7.4   4.0 | -36.8 -34.2  350 118 61   7.9   4.3
 23000 -35.5 -31.9  360 193 99   7.2   4.0 | -34.4 -29.9  355 117 60   7.7   4.2
 22000 -33.3 -27.9  360 196 101   7.2   4.0 | -32.1 -25.8  355  98 50   7.7   4.2
 21000 -31.2 -24.2  360 200 103   7.2   3.9 | -29.8 -21.6  350  79 41   7.7   4.2
 20000 -29.1 -20.4  360 166 85   6.1   3.3 | -27.6 -17.7  350  66 34   6.9   3.8
 19500 -28.2 -18.8  360 125 64   6.1   3.3 | -26.6 -15.9  350  63 32   6.8   3.7
 19000 -27.3 -17.1  355  84 43   6.0   3.3 | -25.6 -14.1  350  59 30   6.8   3.7
 18500 -26.4 -15.5  355  43 22   6.0   3.3 | -24.6 -12.3  350  55 29   6.8   3.7
 18000 -25.5 -13.9  285   6  3   5.0   2.7 | -23.5 -10.3  350  52 27   6.8   3.8
 17500 -25.0 -13.0  230   9  5   2.6   1.4 | -22.5  -8.5  345  43 22   6.9   3.8
 17000 -24.6 -12.3  230  11  5   3.0   1.6 | -21.5  -6.7  340  34 18   6.9   3.8
 16500 -24.5 -12.1  240  10  5  -0.5  -0.3 | -20.7  -5.3  330  21 11   3.4   1.9
 16000 -24.5 -12.1  265   9  5  -0.3  -0.2 | -20.2  -4.4  265  11  6   4.2   2.3
 15500 -24.3 -11.7  290  11  5   5.0   2.7 | -20.0  -4.0  210  22 11  -2.9  -1.6
 15000 -23.4 -10.1  295  12  6   6.1   3.3 | -20.6  -5.1  200  37 19  -3.6  -2.0
 14500 -22.5  -8.5  295  12  6   8.1   4.5 | -21.0  -5.8  195  50 26   4.0   2.2
 14000 -21.1  -6.0  225  15  8   9.4   5.1 | -19.8  -3.6  195  49 25   7.8   4.3
 13500 -19.7  -3.5  205  29 15  10.1   5.6 | -18.6  -1.5  190  49 25   9.7   5.3
 13000 -18.1  -0.6  195  38 20  11.2   6.1 | -16.9   1.6  190  54 28  12.1   6.7
 12500 -16.7   1.9  190  49 25   6.1   3.4 | -15.8   3.6  190  64 33   5.6   3.1
 12000 -15.5   4.1  190  55 28   9.9   5.4 | -14.4   6.1  185  64 33   9.9   5.4
 11750 -14.8   5.4  190  58 30   9.0   4.9 | -13.6   7.5  185  64 33   9.6   5.3
 11500 -14.1   6.6  190  60 31  11.0   6.0 | -12.9   8.8  185  65 33  11.0   6.0
 11250 -13.3   8.1  185  66 34  10.5   5.8 | -12.0  10.4  185  68 35  10.4   5.7
 11000 -12.6   9.3  185  70 36   8.4   4.6 | -11.4  11.5  185  68 35   8.6   4.7
 10750 -11.9  10.6  185  74 38   9.0   5.0 | -10.7  12.7  185  69 35   9.2   5.0
 10500 -11.3  11.7  185  79 41   8.3   4.5 | -10.0  14.0  185  71 36   8.4   4.6
 10250 -10.6  12.9  185  88 45   9.0   5.0 |  -9.4  15.1  185  83 42   9.0   4.9
 10000  -9.9  14.2  185  95 49  10.6   5.8 |  -8.7  16.3  185  85 44  10.3   5.7
  9750  -9.1  15.6  185 100 52  10.2   5.6 |  -7.9  17.8  185  85 44   9.9   5.5
  9500  -8.4  16.9  185 109 56   8.9   4.9 |  -7.2  19.0  185  90 46   9.0   5.0
  9250  -7.8  18.0  180 122 63   8.6   4.7 |  -6.6  20.1  185 102 53   8.7   4.8
  9000  -7.1  19.2  180 134 69  10.1   5.5 |  -5.9  21.4  180 113 58   9.6   5.2
  8750  -6.3  20.7  180 145 75  10.3   5.7 |  -5.1  22.8  180 121 62   9.5   5.2
  8500  -5.6  21.9  180 155 80   9.8   5.4 |  -4.5  23.9  180 131 67   8.8   4.8
  8250  -4.8  23.4  180 164 84   9.7   5.3 |  -3.8  25.2  180 141 73   9.0   4.9
  8000  -4.1  24.6  180 173 89   9.5   5.2 |  -3.2  26.2  180 153 79   8.2   4.5
  7750  -3.3  26.1  180 183 94  12.2   6.7 |  -2.7  27.1  180 172 89   3.8   2.1
  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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