Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 261127
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0527 MDT Sunday, April 26, 2015

This forecast is for Sunday, April 26, 2015:

If the trigger temperature of 52.9 F/11.6 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 299 ft/min (1.5 m/s)
   Maximum height of thermals.................. 10072 ft MSL (2901 ft AGL)

Forecast maximum temperature................... 47.0 F/8.8 C
Time of trigger temperature.................... None
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................. None
Thermal soaring outlook for Monday 04/27....... Fair

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

Remarks...

Sunrise/Sunset.................... 06:07:41 / 19:45:44 MDT
Total possible sunshine........... 13 hr 38 min 2 sec (818 min 2 sec)
Altitude of sun at 12:56:52 MDT... 64.64 degrees

Upper air data from numerical model forecast valid on 04/26/2015 at 0600 MDT

Freezing level.................. 9624 ft MSL (2453 ft AGL)
Convective condensation level... 12098 ft MSL (4927 ft AGL)
Lifted condensation level....... 10425 ft MSL (3254 ft AGL)
Lifted index.................... -0.0
K index......................... +18.1

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  -55.4 -67.7   245   29   15   1.5   0.8      M     M       M      M    M
 45000  -53.2 -63.8   240   33   17   1.6   0.9      M     M       M      M    M
 40000  -55.2 -67.4   230   32   17  -1.4  -0.8      M     M       M      M    M
 38000  -56.0 -68.8   220   29   15  -1.2  -0.7      M     M       M      M    M
 36000  -56.7 -70.1   195   22   11  -1.2  -0.7      M     M       M      M    M
 34000  -57.3 -71.1   165   21   11   4.6   2.5      M     M       M      M    M
 32000  -52.4 -62.3   160   21   11   8.2   4.5      M     M       M      M    M
 30000  -47.4 -53.3   160   21   11   9.3   5.1   22.1  71.8    10.5      M    M
 29000  -44.6 -48.3   165   22   11   9.4   5.2   21.8  71.3    10.5      M    M
 28000  -41.7 -43.1   170   22   12   9.4   5.2   21.7  71.1    10.5      M    M
 27000  -38.2 -36.8   175   24   12   9.2   5.0   21.7  71.1    10.7      M    M
 26000  -35.6 -32.1   175   24   12   8.6   4.7   21.2  70.2    10.4      M    M
 25000  -33.0 -27.4   175   25   13   8.6   4.7   20.8  69.4    10.2      M    M
 24000  -30.4 -22.7   180   25   13   8.6   4.7   20.5  68.9    10.0      M    M
 23000  -28.0 -18.4   180   25   13   8.0   4.4   19.8  67.7     9.6      M    M
 22000  -25.6 -14.1   185   26   13   8.0   4.4   19.2  66.6     9.2      M    M
 21000  -23.2  -9.8   185   26   13   7.6   4.2   18.7  65.7     8.8      M    M
 20000  -21.1  -6.0   190   23   12   7.0   3.9   17.7  63.8     8.0      M    M
 19500  -20.0  -4.0   190   22   11   7.0   3.9   17.2  63.0     7.6      M    M
 19000  -19.0  -2.2   190   21   11   7.0   3.9   16.8  62.2     7.3      M    M
 18500  -18.0  -0.4   195   20   10   7.1   3.9   16.3  61.4     6.9      M    M
 18000  -16.9   1.6   195   19   10   7.3   4.0   15.9  60.6     6.6      M    M
 17500  -15.8   3.6   195   19   10   7.2   4.0   15.5  59.9     6.2      M    M
 17000  -14.7   5.5   195   18    9   8.0   4.4   15.1  59.2     5.9      M    M
 16500  -13.5   7.7   190   18    9   8.1   4.4   14.8  58.7     5.7      M    M
 16000  -12.3   9.9   190   18    9   8.4   4.6   14.6  58.2     5.4      M    M
 15500  -11.1  12.0   190   17    9   8.7   4.8   14.4  57.9     5.2      M    M
 15000   -9.8  14.4   185   17    9   8.8   4.8   14.2  57.6     5.1      M    M
 14500   -8.5  16.7   185   17    9   8.8   4.8   14.1  57.3     4.9      M    M
 14000   -7.3  18.9   185   16    8   8.9   4.9   13.9  57.1     4.7      M    M
 13500   -6.0  21.2   185   16    8   8.7   4.8   13.8  56.8     4.6      M    M
 13000   -4.7  23.5   185   15    8   8.7   4.8   13.6  56.5     4.4      M    M
 12500   -3.4  25.9   185   14    7   8.8   4.8   13.4  56.2     4.3      M    M
 12000   -2.2  28.0   190   13    6   7.6   4.1   13.2  55.8     4.1      M    M
 11750   -1.7  28.9   195   12    6   7.0   3.8   13.0  55.4     3.9      M    M
 11500   -1.2  29.8   195   11    6   6.2   3.4   12.8  55.0     3.6      M    M
 11250   -0.7  30.7   200   11    5   6.2   3.4   12.5  54.4     3.4      M    M
 11000   -0.3  31.5   200   10    5   5.2   2.9   12.2  53.9     3.1      M    M
 10750   -0.0  32.0   205   10    5   2.0   1.1   11.7  53.1     2.6      M    M
 10500   -0.0  32.0   195   10    5  -0.5  -0.3   11.0  51.8     1.9      M    M
 10250   -0.3  31.5   175   12    6  -1.5  -0.8    9.3  48.8     0.2      M    M
 10000   -0.4  31.3   165   13    7   1.8   1.0    8.5  47.3    -0.7    296  1.5
  9750   -0.0  32.0   160   14    7   7.6   4.2    8.2  46.7    -1.0    278  1.4
  9500    0.6  33.1   155   15    8   8.5   4.6    8.0  46.5    -1.2    253  1.3
  9250    1.1  34.0   150   16    8   8.4   4.6    7.9  46.3    -1.3    228  1.2
  9000    1.7  35.1   150   18    9   8.1   4.4    7.8  46.1    -1.5    203  1.0
  8750    2.3  36.1   145   16    8   8.3   4.6    7.7  45.8    -1.7    179  0.9
  8500    2.9  37.2   140   16    8   8.9   4.9    7.6  45.7    -1.8    153  0.8
  8250    3.5  38.3   135   15    8   8.7   4.8    7.5  45.6    -1.9    127  0.6
  8000    4.1  39.4   135   14    7   7.8   4.3    7.4  45.4    -2.0    102  0.5
  7750    4.6  40.3   130   12    6   7.9   4.3    7.3  45.1    -2.2     79  0.4
  7500    5.3  41.5   130    9    5   9.9   5.4    7.2  45.0    -2.3     52  0.3
  7250    5.9  42.6   125    6    3   5.8   3.2    7.1  44.9    -2.4     26  0.1
  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 * * * * * *

           04/26/2015 at 0900 MDT          |       04/26/2015 at 1200 MDT
                                           |
K index... +18.8  LI... +272.0             | K index... +18.6  LI... +272.3
CAPE... +163.7  CIN... -16.6               | CAPE... +70.5  CIN... -30.6
                                           |
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 -55.1 -67.2  245  26 13   1.2   0.7 | -54.8 -66.6  245  22 11   1.0   0.6
 45000 -53.1 -63.6  245  28 14   0.8   0.5 | -53.2 -63.8  240  21 11   0.7   0.4
 40000 -54.8 -66.6  225  28 15  -1.2  -0.7 | -54.6 -66.3  225  22 12  -1.0  -0.6
 38000 -55.6 -68.1  215  26 13  -1.3  -0.7 | -55.3 -67.5  210  21 11  -1.4  -0.8
 36000 -56.4 -69.5  195  20 10  -1.3  -0.7 | -56.2 -69.2  185  20 10  -1.4  -0.8
 34000 -57.0 -70.6  170  18  9   4.2   2.3 | -56.9 -70.4  160  22 11   4.1   2.3
 32000 -52.2 -62.0  160  20 10   8.1   4.4 | -52.1 -61.8  160  25 13   8.0   4.4
 30000 -47.3 -53.1  160  23 12   9.4   5.2 | -47.2 -53.0  155  27 14   9.3   5.1
 29000 -44.4 -47.9  160  24 13   9.6   5.3 | -44.4 -47.9  160  27 14   9.4   5.2
 28000 -41.5 -42.7  160  26 13   9.6   5.3 | -40.8 -41.4  160  27 14   9.4   5.2
 27000 -38.0 -36.4  160  27 14   9.3   5.1 | -38.0 -36.4  160  27 14   9.3   5.1
 26000 -35.4 -31.7  160  28 14   8.5   4.7 | -35.3 -31.5  160  27 14   9.0   4.9
 25000 -32.8 -27.0  160  27 14   8.5   4.7 | -32.6 -26.7  165  27 14   9.0   4.9
 24000 -30.3 -22.5  160  27 14   8.5   4.7 | -29.9 -21.8  165  28 14   9.0   5.0
 23000 -28.0 -18.4  160  27 14   7.6   4.2 | -27.6 -17.7  160  28 14   7.4   4.1
 22000 -25.7 -14.3  165  26 13   7.6   4.2 | -25.4 -13.7  155  28 14   7.4   4.1
 21000 -23.4 -10.1  165  25 13   7.5   4.1 | -23.2  -9.8  150  28 14   7.2   3.9
 20000 -21.2  -6.2  160  24 12   7.3   4.0 | -21.1  -6.0  150  27 14   6.8   3.7
 19500 -20.2  -4.4  160  24 12   7.3   4.0 | -20.1  -4.2  145  27 14   6.8   3.7
 19000 -19.1  -2.4  155  24 12   7.4   4.0 | -19.1  -2.4  145  27 14   6.8   3.7
 18500 -18.0  -0.4  155  23 12   7.4   4.1 | -18.1  -0.6  145  27 14   6.8   3.7
 18000 -16.9   1.6  150  24 12   7.6   4.2 | -17.1   1.2  145  27 14   6.9   3.8
 17500 -15.7   3.7  150  24 12   7.6   4.2 | -16.1   3.0  145  28 14   6.8   3.8
 17000 -14.6   5.7  150  24 12   7.6   4.2 | -15.0   5.0  145  28 14   7.3   4.0
 16500 -13.5   7.7  150  24 12   7.6   4.2 | -13.9   7.0  145  28 14   7.4   4.1
 16000 -12.4   9.7  150  23 12   7.6   4.2 | -12.8   9.0  145  28 14   7.6   4.2
 15500 -11.3  11.7  150  22 12   7.6   4.2 | -11.7  10.9  145  27 14   8.0   4.4
 15000 -10.2  13.6  150  22 11   7.6   4.2 | -10.5  13.1  145  27 14   8.1   4.4
 14500  -9.1  15.6  150  20 10   7.6   4.2 |  -9.4  15.1  145  25 13   8.4   4.6
 14000  -8.0  17.6  150  19 10   7.6   4.2 |  -8.2  17.2  145  24 12   8.6   4.7
 13500  -6.9  19.6  150  17  9   7.3   4.0 |  -7.0  19.4  140  22 11   7.2   3.9
 13000  -5.8  21.6  150  15  8   7.4   4.0 |  -6.0  21.2  140  19 10   7.5   4.1
 12500  -4.7  23.5  150  12  6   7.0   3.8 |  -5.0  23.0  135  17  9   5.7   3.1
 12000  -3.7  25.3  150   9  4   5.9   3.2 |  -4.2  24.4  125  14  7   4.4   2.4
 11750  -3.3  26.1  150   6  3   4.9   2.7 |  -3.9  25.0  110  12  6   3.6   2.0
 11500  -3.0  26.6  155   5  2   4.1   2.3 |  -3.7  25.3  110  10  5   3.5   1.9
 11250  -2.7  27.1  165   4  2   3.7   2.0 |  -3.4  25.9  115   9  4   3.3   1.8
 11000  -2.5  27.5  185   4  2   4.6   2.5 |  -3.2  26.2  120   7  4   3.5   1.9
 10750  -2.1  28.2  210   3  2   4.7   2.6 |  -2.9  26.8  125   5  3   4.3   2.4
 10500  -1.8  28.8  205   4  2   3.1   1.7 |  -2.2  28.0  145   8  4   5.1   2.8
 10250  -1.5  29.3  175   7  3   3.5   1.9 |  -1.8  28.8  150  11  6   5.4   3.0
 10000  -1.3  29.7  165   9  4   0.3   0.2 |  -1.5  29.3  155  13  7   4.3   2.4
  9750  -1.4  29.5  160  10  5   3.3   1.8 |  -1.2  29.8  150  15  8   4.4   2.4
  9500  -0.9  30.4  155  12  6   8.7   4.8 |  -0.8  30.6  145  16  8   5.6   3.1
  9250  -0.3  31.5  150  13  7   7.2   4.0 |  -0.5  31.1  140  17  9   5.0   2.8
  9000   0.2  32.4  150  15  8   7.8   4.3 |  -0.1  31.8  135  18  9   5.9   3.2
  8750   0.8  33.4  145  15  8   9.8   5.4 |   0.4  32.7  130  18  9   9.3   5.1
  8500   1.6  34.9  140  15  7  11.3   6.2 |   1.2  34.2  125  17  9  11.1   6.1
  8250   2.4  36.3  135  15  8  10.8   5.9 |   2.0  35.6  125  16  8  10.4   5.7
  8000   3.1  37.6  135  14  7  10.3   5.7 |   2.7  36.9  120  15  8   9.3   5.1
  7750   3.9  39.0  135  12  6  11.9   6.5 |   3.4  38.1  120  14  7  12.6   6.9
  7500   4.9  40.8  130   9  5  15.8   8.6 |   4.6  40.3  120  12  6  20.2  11.1
  7250   5.9  42.6  130   7  4   8.7   4.8 |   5.8  42.4  120  11  5   6.3   3.5
  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

           04/26/2015 at 1500 MDT          |       04/26/2015 at 1800 MDT
                                           |
K index... +18.3  LI... +272.4             | K index... +23.8  LI... +273.7
CAPE... +44.2  CIN... -23.3                | CAPE... +15.8  CIN... -3.6
                                           |
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 -55.4 -67.7  260  20 10   1.2   0.6 | -55.1 -67.2  275  14  7   0.6   0.3
 45000 -53.6 -64.5  245  20 10   0.7   0.4 | -54.2 -65.6  280  13  6   0.4   0.2
 40000 -54.7 -66.5  240  14  7  -0.8  -0.5 | -55.1 -67.2  300   4  2  -0.7  -0.4
 38000 -55.4 -67.7  220  13  7  -1.4  -0.8 | -55.7 -68.3  270   2  1  -1.3  -0.7
 36000 -56.2 -69.2  195  16  8  -1.4  -0.8 | -56.4 -69.5  225   7  4  -1.3  -0.7
 34000 -56.9 -70.4  180  22 11   5.1   2.8 | -57.0 -70.6  220  13  7   5.3   2.9
 32000 -51.7 -61.1  170  23 12   8.7   4.8 | -51.0 -59.8  205  11  5   8.9   4.9
 30000 -46.4 -51.5  160  25 13   9.5   5.2 | -45.6 -50.1  185   9  5   9.4   5.1
 29000 -42.9 -45.2  155  26 13   9.4   5.2 | -42.8 -45.0  175  10  5   9.4   5.1
 28000 -40.1 -40.2  145  27 14   9.4   5.2 | -40.0 -40.0  165  10  5   9.4   5.2
 27000 -37.2 -35.0  140  29 15   9.0   4.9 | -37.2 -35.0  155  11  6   9.1   5.0
 26000 -34.8 -30.6  140  27 14   8.1   4.5 | -34.7 -30.5  150  14  7   8.2   4.5
 25000 -32.4 -26.3  135  25 13   8.1   4.5 | -32.3 -26.1  150  17  9   8.2   4.5
 24000 -29.9 -21.8  130  23 12   8.1   4.5 | -29.8 -21.6  150  20 10   8.2   4.5
 23000 -27.4 -17.3  135  22 11   8.7   4.8 | -27.4 -17.3  150  20 10   8.3   4.5
 22000 -24.8 -12.6  140  21 11   8.7   4.8 | -24.9 -12.8  150  20 10   8.3   4.6
 21000 -22.2  -8.0  145  20 10   7.3   4.0 | -22.5  -8.5  150  19 10   7.8   4.3
 20000 -20.5  -4.9  145  23 12   5.5   3.0 | -20.4  -4.7  150  21 11   6.9   3.8
 19500 -19.7  -3.5  140  24 12   5.5   3.0 | -19.4  -2.9  150  22 11   6.9   3.8
 19000 -18.8  -1.8  140  26 13   5.6   3.0 | -18.3  -0.9  155  23 12   6.9   3.8
 18500 -18.0  -0.4  140  27 14   5.8   3.2 | -17.3   0.9  155  24 12   6.9   3.8
 18000 -17.0   1.4  135  28 14   6.9   3.8 | -16.4   2.5  155  25 13   5.9   3.2
 17500 -16.0   3.2  135  28 15   6.8   3.8 | -15.5   4.1  155  27 14   6.0   3.3
 17000 -15.0   5.0  135  28 15   6.8   3.7 | -14.7   5.5  155  29 15   5.6   3.1
 16500 -14.0   6.8  135  28 14   6.8   3.8 | -13.9   7.0  150  31 16   5.5   3.0
 16000 -13.1   8.4  135  28 14   7.5   4.1 | -13.1   8.4  145  32 17   5.9   3.2
 15500 -11.9  10.6  135  27 14   8.4   4.6 | -11.6  11.1  140  33 17   6.7   3.7
 15000 -10.7  12.7  135  27 14   8.6   4.7 | -10.6  12.9  135  34 17   7.0   3.8
 14500  -9.3  15.3  140  26 13   9.8   5.4 |  -9.6  14.7  135  32 17   7.2   3.9
 14000  -7.9  17.8  140  25 13  10.3   5.7 |  -8.5  16.7  135  31 16   7.7   4.2
 13500  -6.8  19.8  140  23 12   4.8   2.6 |  -7.3  18.9  135  29 15   8.4   4.6
 13000  -6.1  21.0  140  21 11   5.3   2.9 |  -6.1  21.0  140  26 13   8.1   4.5
 12500  -5.3  22.5  140  18  9   5.4   2.9 |  -5.0  23.0  135  23 12   7.3   4.0
 12000  -4.5  23.9  130  15  8   4.7   2.6 |  -4.1  24.6  130  18  9   4.5   2.5
 11750  -4.2  24.4  125  14  7   4.6   2.5 |  -3.8  25.2  125  15  8   4.3   2.3
 11500  -3.8  25.2  120  12  6   5.2   2.9 |  -3.5  25.7  115  14  7   3.9   2.2
 11250  -3.5  25.7  115  11  6   4.9   2.7 |  -3.2  26.2  105  12  6   4.0   2.2
 11000  -3.1  26.4  110  10  5   6.3   3.5 |  -3.0  26.6  095  11  6   4.2   2.3
 10750  -2.6  27.3  100  10  5   7.0   3.8 |  -2.6  27.3  090  10  5   4.6   2.5
 10500  -1.8  28.8  115  10  5   4.5   2.4 |  -2.3  27.9  085  11  5   4.5   2.5
 10250  -1.5  29.3  125  11  5   4.4   2.4 |  -2.0  28.4  080  11  6   5.0   2.7
 10000  -1.2  29.8  135  12  6   5.1   2.8 |  -1.7  28.9  075  11  6   3.3   1.8
  9750  -0.9  30.4  140  13  6   2.3   1.3 |  -1.5  29.3  080  12  6   2.5   1.4
  9500  -0.8  30.6  135  14  7  -0.3  -0.2 |  -1.2  29.8  090  13  6   3.8   2.1
  9250  -0.8  30.6  130  15  8  -0.1  -0.1 |  -1.0  30.2  095  13  7   2.9   1.6
  9000  -0.7  30.7  125  16  8   4.3   2.4 |  -0.7  30.7  105  15  7   5.0   2.8
  8750  -0.2  31.6  120  15  8   8.4   4.6 |  -0.2  31.6  100  15  8   8.3   4.5
  8500   0.3  32.5  115  15  8   7.2   3.9 |   0.4  32.7  100  15  8   8.6   4.7
  8250   0.9  33.6  110  15  7   8.2   4.5 |   1.0  33.8  095  14  7   8.6   4.7
  8000   1.5  34.7  110  14  7   9.5   5.2 |   1.6  34.9  095  14  7   9.5   5.2
  7750   2.3  36.1  110  12  6  12.7   7.0 |   2.3  36.1  095  12  6   9.2   5.1
  7500   3.4  38.1  110  11  5  17.0   9.3 |   2.9  37.2  095  11  5   8.5   4.7
  7250   4.4  39.9  105   9  5   9.6   5.3 |   3.5  38.3  095   9  5   7.7   4.2
  7000     M     M    M   M  M     M     M |   4.0  39.2  090   8  4   5.6   3.0
  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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