Soaring Guidance
Issued by NWS Pueblo, CO

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902
UXUS97 KPUB 291253
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0653 MDT Friday, April 29, 2016

This forecast is for Friday, April 29, 2016:

If the trigger temperature of 40.2 F/4.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9108 ft MSL (2350 ft AGL)

Forecast maximum temperature................... 33.0 F/1.0 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
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................. None
Thermal soaring outlook for Saturday 04/30..... Poor

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

Remarks...

Sunrise/Sunset.................... 06:02:57 / 19:49:23 MDT
Total possible sunshine........... 13 hr 46 min 26 sec (826 min 26 sec)
Altitude of sun at 12:56:20 MDT... 65.82 degrees

Upper air data from numerical model forecast valid on 04/29/2016 at 0600 MDT

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 12445 ft MSL (5687 ft AGL)
Lifted condensation level....... 8933 ft MSL (2176 ft AGL)
Lifted index.................... +8.8
K index......................... +19.6

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  -55.3 -67.5   235   26   13   0.9   0.5      M     M       M      M    M
 45000  -53.9 -65.0   225   28   14   0.6   0.3      M     M       M      M    M
 40000  -55.1 -67.2   210   41   21  -0.9  -0.5      M     M       M      M    M
 38000  -55.3 -67.5   210   46   24   0.8   0.4      M     M       M      M    M
 36000  -54.8 -66.6   205   52   27   0.8   0.4      M     M       M      M    M
 34000  -54.3 -65.7   200   58   30   2.6   1.4      M     M       M      M    M
 32000  -51.5 -60.7   195   58   30   4.8   2.6      M     M       M      M    M
 30000  -47.9 -54.2   185   58   30   9.6   5.3   21.3  70.4    15.9      M    M
 29000  -45.1 -49.2   190   58   30   9.2   5.1   21.0  69.8    15.8      M    M
 28000  -42.4 -44.3   190   57   29   9.2   5.1   20.8  69.4    15.9      M    M
 27000  -39.6 -39.3   190   57   29   9.2   5.1   20.7  69.3    16.0      M    M
 26000  -36.9 -34.4   190   51   26   9.2   5.1   20.4  68.8    16.0      M    M
 25000  -34.1 -29.4   190   44   23   9.2   5.1   20.2  68.4    16.0      M    M
 24000  -31.3 -24.3   190   37   19   9.3   5.1   20.1  68.2    16.1      M    M
 23000  -28.7 -19.7   190   33   17   8.7   4.8   19.7  67.5    16.0      M    M
 22000  -26.1 -15.0   185   29   15   8.8   4.8   19.4  66.9    15.8      M    M
 21000  -23.5 -10.3   185   26   13   8.1   4.5   19.1  66.4    15.8      M    M
 20000  -21.5  -6.7   190   23   12   6.6   3.6   18.0  64.4    14.9      M    M
 19500  -20.5  -4.9   190   22   11   6.6   3.6   17.5  63.4    14.5      M    M
 19000  -19.6  -3.3   195   21   11   6.6   3.6   16.9  62.5    14.1      M    M
 18500  -18.6  -1.5   195   20   10   6.6   3.6   16.5  61.6    13.7      M    M
 18000  -17.6   0.3   195   20   11   6.6   3.6   15.9  60.7    13.3      M    M
 17500  -16.7   1.9   195   22   11   6.5   3.6   15.4  59.7    12.9      M    M
 17000  -15.7   3.7   190   24   12   7.1   3.9   14.9  58.8    12.5      M    M
 16500  -14.6   5.7   190   25   13   7.3   4.0   14.5  58.0    12.2      M    M
 16000  -13.6   7.5   185   26   13   6.9   3.8   14.1  57.3    11.9      M    M
 15500  -12.6   9.3   185   26   13   6.0   3.3   13.5  56.3    11.4      M    M
 15000  -11.8  10.8   185   25   13   6.0   3.3   12.9  55.2    10.9      M    M
 14500  -10.5  13.1   185   20   10   5.5   3.0   11.9  53.4    10.0      M    M
 14000   -9.7  14.5   190   17    9   5.4   3.0   11.2  52.1     9.4      M    M
 13500   -8.9  16.0   185   13    7   5.3   2.9   10.5  50.8     8.8      M    M
 13000   -8.1  17.4   180   10    5   5.1   2.8    9.8  49.6     8.2      M    M
 12500   -7.4  18.7   165    8    4   4.7   2.6    9.0  48.1     7.4      M    M
 12000   -6.8  19.8   145    8    4   2.9   1.6    8.1  46.5     6.6      M    M
 11750   -6.7  19.9   140    8    4   2.3   1.3    7.5  45.5     6.1      M    M
 11500   -6.5  20.3   135    9    4   2.0   1.1    6.9  44.4     5.5      M    M
 11250   -6.3  20.7   135    9    5   2.7   1.5    6.3  43.3     5.0      M    M
 11000   -6.2  20.8   130   10    5   0.3   0.1    5.7  42.3     4.4      M    M
 10750   -6.2  20.8   130   10    5   0.2   0.1    4.9  40.8     3.6      M    M
 10500   -6.1  21.0   130   11    6   2.7   1.5    4.3  39.7     3.1      M    M
 10250   -5.9  21.4   130   11    6   2.1   1.1    3.7  38.7     2.5      M    M
 10000   -5.8  21.6   130   12    6   2.1   1.2    3.1  37.6     1.9      M    M
  9750   -5.6  21.9   130   12    6   2.1   1.2    2.5  36.5     1.4      M    M
  9500   -5.5  22.1   125   12    6   2.4   1.3    1.9  35.5     0.8      M    M
  9250   -5.3  22.5   125   12    6   2.1   1.2    1.4  34.5     0.2      M    M
  9000   -5.1  22.8   120   12    6   3.7   2.0    0.8  33.5    -0.3    236  1.2
  8750   -4.7  23.5   120   12    6   5.4   3.0    0.5  32.8    -0.7    218  1.1
  8500   -4.4  24.1   120   12    6   5.2   2.8    0.1  32.2    -1.0    199  1.0
  8250   -4.0  24.8   120   11    6   5.5   3.0   -0.2  31.6    -1.4    180  0.9
  8000   -3.6  25.5   120   10    5   6.0   3.3   -0.5  31.1    -1.7    160  0.8
  7750   -3.1  26.4   120    9    5   6.7   3.7   -0.8  30.6    -2.0    139  0.7
  7500   -2.6  27.3   120    7    3   7.7   4.2   -1.0  30.3    -2.2    116  0.6
  7250   -2.1  28.2   120    5    2   5.6   3.1   -1.1  30.0    -2.4     93  0.5
  7000   -1.8  28.8   120    4    2   1.2   0.7   -1.0  30.2    -2.3     78  0.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           04/29/2016 at 0900 MDT          |       04/29/2016 at 1200 MDT
                                           |
K index... +18.1  LI... +274.9             | K index... +12.5  LI... +274.8
CAPE... 0.0  CIN... M                      | CAPE... +3.1  CIN... -18.2
                                           |
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 -54.8 -66.6  235  32 16  -0.1  -0.1 | -54.2 -65.6  235  30 16   0.1   0.1
 45000 -55.0 -67.0  220  37 19   0.1   0.0 | -54.0 -65.2  225  35 18   0.2   0.1
 40000 -53.9 -65.0  195  40 20   0.8   0.4 | -53.0 -63.4  200  35 18   0.7   0.4
 38000 -53.4 -64.1  190  43 22   0.9   0.5 | -52.3 -62.1  190  36 18   2.1   1.2
 36000 -52.9 -63.2  185  48 24   0.9   0.5 | -51.0 -59.8  180  36 18   2.1   1.2
 34000 -52.3 -62.1  180  52 27   1.6   0.9 | -49.7 -57.5  175  36 19   2.2   1.2
 32000 -50.5 -58.9  175  50 26   3.1   1.7 | -47.8 -54.0  165  36 18   2.9   1.6
 30000 -48.0 -54.4  170  48 25  10.3   5.6 | -45.9 -50.6  160  35 18   5.2   2.9
 29000 -45.2 -49.4  170  48 25   9.4   5.2 | -44.2 -47.6  160  35 18   5.7   3.1
 28000 -42.4 -44.3  170  49 25   9.5   5.2 | -42.5 -44.5  155  35 18   5.7   3.1
 27000 -39.5 -39.1  165  49 25   9.5   5.2 | -40.8 -41.4  155  35 18   5.6   3.1
 26000 -36.8 -34.2  170  47 24   9.0   4.9 | -38.7 -37.7  155  35 18   7.7   4.2
 25000 -34.1 -29.4  170  45 23   9.0   4.9 | -36.4 -33.5  155  35 18   7.8   4.3
 24000 -31.5 -24.7  175  43 22   9.2   5.0 | -34.0 -29.2  160  35 18   7.8   4.3
 23000 -29.2 -20.6  175  41 21   7.1   3.9 | -31.6 -24.9  160  33 17   8.3   4.5
 22000 -27.0 -16.6  180  38 20   7.2   3.9 | -29.1 -20.4  165  31 16   8.3   4.5
 21000 -24.9 -12.8  185  36 19   7.4   4.0 | -26.7 -16.1  170  30 15   8.3   4.5
 20000 -22.5  -8.5  185  34 17   8.4   4.6 | -24.1 -11.4  175  28 14   8.8   4.8
 19500 -21.2  -6.2  180  33 17   8.4   4.6 | -22.7  -8.9  175  27 14   8.8   4.8
 19000 -20.0  -4.0  180  32 16   8.4   4.6 | -21.4  -6.5  180  26 13   8.8   4.8
 18500 -18.8  -1.8  180  31 16   8.5   4.7 | -20.1  -4.2  180  25 13   8.9   4.9
 18000 -17.6   0.3  175  30 15   6.8   3.7 | -18.9  -2.0  180  24 12   7.7   4.2
 17500 -16.6   2.1  175  29 15   7.0   3.8 | -17.7   0.1  180  22 11   7.7   4.2
 17000 -15.6   3.9  170  29 15   7.2   4.0 | -16.6   2.1  175  20 10   6.9   3.8
 16500 -14.5   5.9  170  29 15   7.3   4.0 | -15.7   3.7  175  20 10   6.4   3.5
 16000 -13.5   7.7  170  28 14   7.4   4.1 | -14.8   5.4  170  20 10   6.8   3.7
 15500 -12.4   9.7  170  27 14   7.7   4.2 | -12.9   8.8  165  21 11   9.5   5.2
 15000 -11.3  11.7  170  27 14   8.2   4.5 | -11.5  11.3  165  22 11   7.6   4.2
 14500 -10.1  13.8  165  26 13   4.3   2.3 | -10.8  12.6  160  23 12   4.6   2.5
 14000  -9.5  14.9  160  25 13   3.7   2.0 | -10.1  13.8  155  23 12   3.7   2.1
 13500  -9.1  15.6  150  20 10   2.3   1.3 |  -9.9  14.2  155  20 11  -0.2  -0.1
 13000  -8.7  16.3  135  14  7   2.5   1.4 |  -9.9  14.2  150  16  8   0.2   0.1
 12500  -8.3  17.1  120  13  7   3.6   2.0 |  -9.5  14.9  145  14  7   4.3   2.4
 12000  -7.8  18.0  105  14  7   2.1   1.1 |  -9.0  15.8  135  12  6   3.4   1.9
 11750  -7.7  18.1  100  15  8   2.4   1.3 |  -8.7  16.3  130  11  6   4.3   2.4
 11500  -7.5  18.5  100  16  8   2.7   1.5 |  -8.4  16.9  125  11  6   4.9   2.7
 11250  -7.3  18.9  100  16  8   2.6   1.4 |  -8.0  17.6  120  12  6   5.0   2.7
 11000  -7.1  19.2  100  16  8   2.9   1.6 |  -7.6  18.3  115  12  6   4.1   2.2
 10750  -6.9  19.6  100  16  8   3.2   1.8 |  -7.4  18.7  110  12  6   3.3   1.8
 10500  -6.6  20.1  095  16  8   3.2   1.8 |  -7.1  19.2  105  12  6   3.7   2.1
 10250  -6.4  20.5  095  16  8   3.2   1.8 |  -6.9  19.6  100  12  6   3.7   2.1
 10000  -6.2  20.8  090  15  8   3.2   1.8 |  -6.6  20.1  090  12  6   3.3   1.8
  9750  -5.9  21.4  090  15  8   3.4   1.9 |  -6.3  20.7  085  11  6   4.1   2.2
  9500  -5.6  21.9  085  14  7   3.7   2.0 |  -6.0  21.2  080  10  5   5.1   2.8
  9250  -5.4  22.3  085  14  7   3.4   1.8 |  -5.6  21.9  080  10  5   4.6   2.5
  9000  -5.1  22.8  085  13  7   4.5   2.5 |  -5.3  22.5  075   9  5   5.6   3.1
  8750  -4.7  23.5  085  12  6   6.7   3.7 |  -4.8  23.4  070   9  4   7.3   4.0
  8500  -4.2  24.4  085  11  6   7.3   4.0 |  -4.3  24.3  065   8  4   7.7   4.2
  8250  -3.7  25.3  085  10  5   7.2   4.0 |  -3.7  25.3  060   8  4   7.7   4.2
  8000  -3.1  26.4  085   9  5   7.0   3.8 |  -3.1  26.4  055   7  4   8.5   4.6
  7750  -2.6  27.3  085   8  4   7.3   4.0 |  -2.5  27.5  055   6  3   8.7   4.8
  7500  -2.1  28.2  080   7  4   8.5   4.7 |  -1.9  28.6  050   6  3   8.9   4.9
  7250  -1.5  29.3  075   6  3   6.8   3.8 |  -1.2  29.8  050   5  3   7.5   4.1
  7000  -1.1  30.0  075   5  3   2.6   1.4 |  -0.8  30.6  050   5  3   3.8   2.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/29/2016 at 1500 MDT          |       04/29/2016 at 1800 MDT
                                           |
K index... +9.6  LI... +274.8              | K index... +12.3  LI... +276.0
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... -0.5
                                           |
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 -54.5 -66.1  245  29 15   0.8   0.5 | -54.2 -65.6  250  22 12   1.2   0.7
 45000 -53.2 -63.8  235  29 15   0.9   0.5 | -52.4 -62.3  240  22 11   1.2   0.7
 40000 -51.6 -60.9  205  30 16   1.0   0.6 | -50.9 -59.6  220  22 12   1.0   0.6
 38000 -50.9 -59.6  195  30 16   1.4   0.8 | -50.4 -58.7  210  22 11   0.3   0.2
 36000 -50.1 -58.2  185  26 13   1.4   0.8 | -50.2 -58.4  195  17  9   0.3   0.2
 34000 -49.3 -56.7  175  22 12   1.4   0.8 | -50.0 -58.0  180  14  7   0.8   0.4
 32000 -48.5 -55.3  160  19 10   1.1   0.6 | -49.1 -56.4  160  11  6   1.5   0.8
 30000 -47.7 -53.9  145  18  9   5.7   3.2 | -48.2 -54.8  135  11  5   4.4   2.4
 29000 -45.5 -49.9  140  18  9   7.4   4.1 | -46.0 -50.8  145  10  5   7.5   4.1
 28000 -43.3 -45.9  140  18  9   7.4   4.1 | -43.7 -46.7  155   9  4   7.5   4.1
 27000 -41.0 -41.8  135  19 10   7.3   4.0 | -41.5 -42.7  165   8  4   7.5   4.1
 26000 -38.5 -37.3  135  17  9   8.8   4.8 | -39.0 -38.2  185   7  4   8.8   4.8
 25000 -35.9 -32.6  145  14  7   8.8   4.8 | -36.4 -33.5  220   7  3   8.8   4.8
 24000 -33.2 -27.8  160  11  6   8.8   4.8 | -33.8 -28.8  250   9  4   8.8   4.9
 23000 -30.7 -23.3  170  10  5   8.1   4.5 | -30.4 -22.7  265  10  5   8.9   4.9
 22000 -28.3 -18.9  175  11  5   8.1   4.4 | -27.8 -18.0  270   9  5   9.0   4.9
 21000 -25.9 -14.6  175  11  5   8.2   4.5 | -25.1 -13.2  275   8  4   8.7   4.8
 20000 -23.7 -10.7  175  13  7   7.1   3.9 | -22.8  -9.0  275   8  4   7.6   4.2
 19500 -22.6  -8.7  175  15  8   7.1   3.9 | -21.7  -7.1  275   8  4   7.6   4.2
 19000 -21.5  -6.7  175  17  9   7.1   3.9 | -20.5  -4.9  270   8  4   7.6   4.2
 18500 -20.4  -4.7  175  18  9   7.2   3.9 | -19.4  -2.9  270   8  4   7.7   4.2
 18000 -19.4  -2.9  180  19 10   6.9   3.8 | -18.3  -0.9  270   8  4   6.8   3.7
 17500 -18.4  -1.1  180  19 10   7.0   3.8 | -17.3   0.9  265   8  4   6.9   3.8
 17000 -17.3   0.9  180  19 10   7.3   4.0 | -16.3   2.7  265   9  5   6.6   3.6
 16500 -16.2   2.8  185  18  9   7.6   4.2 | -15.4   4.3  270   9  5   6.5   3.6
 16000 -15.1   4.8  185  17  9   7.7   4.2 | -14.4   6.1  270  10  5   6.4   3.5
 15500 -13.7   7.3  185  16  8   6.4   3.5 | -13.5   7.7  270  11  5   6.1   3.3
 15000 -12.8   9.0  185  16  8   6.7   3.7 | -12.7   9.1  265  11  6   6.4   3.5
 14500 -11.8  10.8  180  15  8   7.2   3.9 | -12.0  10.4  270  11  6   2.7   1.5
 14000 -10.8  12.6  175  14  7   6.5   3.6 | -11.6  11.1  275  10  5   2.7   1.5
 13500 -10.3  13.5  180  11  6   1.6   0.9 | -11.0  12.2  290  10  5   6.7   3.6
 13000 -10.0  14.0  190   7  3   1.9   1.0 | -10.0  14.0  305  10  5   7.0   3.8
 12500  -9.5  14.9  195   6  3   4.2   2.3 |  -9.1  15.6  315  10  5   3.4   1.9
 12000  -8.9  16.0  195   6  3   4.7   2.6 |  -8.8  16.2  325  10  5   2.8   1.6
 11750  -8.5  16.7  195   6  3   4.8   2.6 |  -8.5  16.7  330  10  5   3.0   1.7
 11500  -8.2  17.2  190   5  3   4.7   2.6 |  -8.3  17.1  335  10  5   3.8   2.1
 11250  -7.8  18.0  185   5  2   4.9   2.7 |  -8.0  17.6  340   9  5   4.1   2.2
 11000  -7.5  18.5  180   4  2   4.1   2.2 |  -7.7  18.1  345   9  5   4.1   2.2
 10750  -7.2  19.0  170   3  2   4.1   2.3 |  -7.4  18.7  350   9  5   4.7   2.6
 10500  -6.9  19.6  155   3  1   5.0   2.7 |  -7.0  19.4  355   9  5   5.1   2.8
 10250  -6.5  20.3  130   2  1   4.7   2.6 |  -6.7  19.9  355   9  5   5.0   2.8
 10000  -6.2  20.8  100   2  1   4.9   2.7 |  -6.3  20.7  360  10  5   5.0   2.7
  9750  -5.8  21.6  075   3  1   5.0   2.7 |  -5.9  21.4  005  10  5   5.2   2.8
  9500  -5.4  22.3  060   3  2   5.0   2.7 |  -5.2  22.6  010  10  5   4.5   2.4
  9250  -5.1  22.8  050   4  2   5.0   2.8 |  -4.9  23.2  015  10  5   4.4   2.4
  9000  -4.7  23.5  045   4  2   4.9   2.7 |  -4.6  23.7  020  10  5   5.3   2.9
  8750  -4.3  24.3  040   5  3   7.2   3.9 |  -4.1  24.6  025  10  5   7.6   4.2
  8500  -3.7  25.3  040   5  3   9.0   4.9 |  -3.5  25.7  030  10  5   8.4   4.6
  8250  -3.1  26.4  040   6  3   8.5   4.7 |  -2.9  26.8  030   9  5   8.5   4.7
  8000  -2.4  27.7  040   6  3   9.0   4.9 |  -2.3  27.9  035   9  5   8.8   4.8
  7750  -1.8  28.8  045   5  3   9.0   4.9 |  -1.6  29.1  035   8  4  11.4   6.2
  7500  -1.1  30.0  050   5  2   9.2   5.0 |  -0.6  30.9  035   8  4  15.9   8.7
  7250  -0.5  31.1  055   5  2   8.0   4.4 |   0.4  32.7  035   7  4   7.8   4.3
  7000  -0.0  32.0  055   5  2   4.9   2.7 |     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) 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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