Soaring Guidance
Issued by NWS Denver/Boulder, CO

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378
UXUS97 KBOU 161230
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0630 MDT Monday, April 16, 2018

This forecast is for Monday, April 16, 2018:

If the trigger temperature of 66.3 F/19.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 935 ft/min (4.7 m/s)
   Maximum height of thermals.................. 17840 ft MSL (12555 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ 1700 MDT
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 15244 ft MSL (9959 ft AGL)
Thermal soaring outlook for Tuesday 04/17...... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 14402 ft MSL (9117 ft AGL)
Wave soaring outlook for Tuesday 04/17......... Good

Remarks... Upper ridge moving over colorado today with very warm temperatures
           and moderate westerly flow aloft.

Sunrise/Sunset.................... 06:19:59 / 19:38:27 MDT
Total possible sunshine........... 13 hr 18 min 28 sec (798 min 28 sec)
Altitude of sun at 12:59:13 MDT... 60.52 degrees

Upper air data from rawinsonde observation taken on 04/16/2018 at 0600 MDT

Freezing level.................. 11965 ft MSL (6680 ft AGL)
Convective condensation level... 19181 ft MSL (13896 ft AGL)
Lifted condensation level....... 18797 ft MSL (13511 ft AGL)
Lifted index.................... +0.9
K index......................... +1.6

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  -60.7 -77.3   270   53   27   5.1   2.8   96.3 205.3    41.0      M    M
 45000  -59.2 -74.6   245   67   35   3.8   2.1   74.1 165.4    30.3      M    M
 40000  -54.2 -65.6   270   83   43   3.4   1.9   58.9 138.1    22.4      M    M
 38000  -52.2 -62.0   270   82   42  -4.4  -2.4   53.3 127.9    19.1      M    M
 36000  -54.5 -66.1   275   92   47  -2.2  -1.2   41.3 106.3    11.3      M    M
 34000  -50.8 -59.4   275   94   48   7.7   4.2   38.1 100.7     9.4      M    M
 32000  -45.6 -50.1   270   81   42   7.8   4.3   36.3  97.3     8.3      M    M
 30000  -41.1 -42.0   270   68   35   7.1   3.9   34.7  94.5     7.3      M    M
 29000  -39.0 -38.2   270   62   32   7.1   3.9   33.6  92.5     6.5      M    M
 28000  -36.7 -34.1   270   57   29   8.2   4.5   32.8  91.0     6.0      M    M
 27000  -34.3 -29.7   270   52   27   8.2   4.5   32.0  89.7     5.5      M    M
 26000  -31.8 -25.2   270   48   24   8.2   4.5   31.5  88.6     5.1      M    M
 25000  -29.4 -20.9   270   43   22   8.2   4.5   31.0  87.8     4.7      M    M
 24000  -26.8 -16.2   270   39   20   8.3   4.6   30.4  86.8     4.3      M    M
 23000  -24.4 -11.9   270   36   18   8.1   4.4   29.7  85.5     3.8      M    M
 22000  -22.0  -7.6   270   32   17   8.1   4.4   29.2  84.5     3.4      M    M
 21000  -19.7  -3.5   265   29   15   7.0   3.9   28.5  83.3     2.9      M    M
 20000  -17.6   0.3   265   26   13   7.6   4.2   27.6  81.6     2.1      M    M
 19500  -16.4   2.5   265   23   12   7.9   4.3   27.2  81.0     1.8      M    M
 19000  -15.2   4.6   265   19   10   8.0   4.4   26.9  80.5     1.5      M    M
 18500  -14.1   6.6   265   19   10   5.7   3.1   26.5  79.6     1.1      M    M
 18000  -13.4   7.9   270   19   10   5.1   2.8   25.6  78.1     0.4      M    M
 17500  -12.7   9.1   270   18    9   5.1   2.8   24.8  76.7    -0.3   1117  5.7
 17000  -11.9  10.6   275   18    9   5.7   3.1   24.1  75.3    -1.0   1080  5.5
 16500  -11.0  12.2   280   21   11   6.3   3.5   23.5  74.3    -1.6   1036  5.3
 16000   -9.5  14.9   285   28   14   6.4   3.5   22.6  72.8    -2.3    971  4.9
 15500   -8.6  16.5   280   31   16   6.4   3.5   22.1  71.7    -2.8    927  4.7
 15000   -7.6  18.3   280   35   18   6.4   3.5   21.5  70.7    -3.4    884  4.5
 14500   -6.6  20.1   275   38   20   7.9   4.3   21.0  69.8    -3.8    839  4.3
 14000   -5.3  22.5   275   40   21   8.8   4.9   20.9  69.6    -4.0    784  4.0
 13500   -3.9  25.0   275   37   19   8.9   4.9   20.7  69.3    -4.1    730  3.7
 13000   -2.6  27.3   275   34   18   8.9   4.9   20.6  69.1    -4.3    675  3.4
 12500   -1.3  29.7   275   31   16   8.9   4.9   20.5  68.9    -4.4    620  3.1
 12000    0.1  32.2   275   28   14   8.9   4.9   20.4  68.7    -4.5    565  2.9
 11500    1.4  34.5   275   26   13   8.9   4.9   20.2  68.4    -4.7    510  2.6
 11000    2.7  36.9   275   24   12   8.9   4.9   20.1  68.1    -4.9    455  2.3
 10500    4.1  39.4   280   22   11   9.0   4.9   19.9  67.9    -5.1    400  2.0
 10250    4.7  40.5   280   21   11   8.8   4.9   19.9  67.7    -5.1    373  1.9
 10000    5.4  41.7   280   20   10   8.1   4.4   19.8  67.6    -5.2    347  1.8
  9750    6.0  42.8   280   19   10   7.6   4.1   19.6  67.3    -5.4    322  1.6
  9500    6.5  43.7   280   18    9   7.8   4.3   19.4  67.0    -5.6    297  1.5
  9250    7.1  44.8   280   17    9   7.2   4.0   19.3  66.7    -5.7    273  1.4
  9000    7.6  45.7   280   16    8   5.5   3.0   19.0  66.3    -6.0    251  1.3
  8750    7.9  46.2   280   13    7   4.8   2.6   18.7  65.6    -6.4    233  1.2
  8500    8.3  46.9   275   10    5   5.0   2.8   18.3  64.9    -6.8    215  1.1
  8250    8.6  47.5   275    7    4   4.9   2.7   17.9  64.3    -7.2    197  1.0
  8000    9.0  48.2   265    4    2   5.3   2.9   17.6  63.6    -7.6    179  0.9
  7750    9.3  48.7   225    5    3   4.0   2.2   17.2  63.0    -8.0    161  0.8
  7500    9.7  49.5   210    8    4   8.8   4.8   16.8  62.3    -8.4    143  0.7
  7250    9.8  49.6   200   11    6 -18.5 -10.2   16.2  61.2    -9.0    133  0.7
  7000    7.2  45.0   195   14    7 -30.1 -16.5   12.9  55.2   -12.3    202  1.0
  6750    5.9  42.6   195   13    6 -14.2  -7.8   10.8  51.5   -14.4    234  1.2
  6500    4.6  40.3   195   11    6 -16.6  -9.1    8.8  47.8   -16.5    266  1.4
  6250    3.7  38.7   200   10    5  -6.7  -3.7    7.1  44.9   -18.2    286  1.5
  6000    3.4  38.1   200    8    4  -2.2  -1.2    6.2  43.1   -19.2    287  1.5
  5750    3.1  37.6   210    5    3  -3.8  -2.1    5.2  41.3   -20.3    289  1.5
  5500    2.8  37.0   245    2    1  -1.9  -1.1    4.2  39.6   -21.4    290  1.5

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

           04/16/2018 at 0900 MDT          |       04/16/2018 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +4.0        | CAPE...     0.0    LI...       +3.3
CINH...    -0.0    K Index...  +9.1        | CINH...    -0.0    K Index... +10.6
                                           |
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 -61.8 -79.2  250  34 18   2.4   1.3 | -61.2 -78.2  250  34 18   1.8   1.0
 45000 -58.1 -72.6  250  41 21   1.2   0.6 | -58.6 -73.5  245  42 22   1.3   0.7
 40000 -56.3 -69.3  260  43 22   1.2   0.7 | -56.6 -69.9  255  42 22   1.3   0.7
 38000 -54.8 -66.6  260  43 22   3.1   1.7 | -55.1 -67.2  255  42 22   3.2   1.8
 36000 -53.0 -63.4  260  43 22   3.1   1.7 | -53.1 -63.6  255  42 21   3.2   1.8
 34000 -49.9 -57.8  265  42 21   7.5   4.1 | -49.9 -57.8  255  40 21   7.7   4.2
 32000 -45.4 -49.7  260  36 19   7.5   4.1 | -45.2 -49.4  255  37 19   7.7   4.2
 30000 -40.8 -41.4  260  31 16   8.1   4.4 | -40.5 -40.9  255  34 17   8.2   4.5
 29000 -38.3 -36.9  260  28 15   8.1   4.4 | -38.1 -36.6  255  32 16   8.2   4.5
 28000 -35.9 -32.6  260  26 13   8.1   4.4 | -35.6 -32.1  255  29 15   8.2   4.5
 27000 -33.5 -28.3  260  23 12   7.6   4.1 | -33.3 -27.9  250  27 14   7.1   3.9
 26000 -31.3 -24.3  260  21 11   7.6   4.2 | -31.1 -24.0  250  23 12   7.3   4.0
 25000 -29.0 -20.2  260  19 10   7.6   4.2 | -28.9 -20.0  250  20 10   7.3   4.0
 24000 -26.7 -16.1  260  16  8   7.7   4.2 | -26.7 -16.1  250  17  9   7.7   4.2
 23000 -24.4 -11.9  260  15  8   7.7   4.2 | -24.4 -11.9  250  16  8   7.9   4.3
 22000 -22.1  -7.8  255  14  7   7.7   4.2 | -22.0  -7.6  250  14  7   7.9   4.3
 21000 -19.9  -3.8  255  12  6   7.1   3.9 | -19.7  -3.5  250  13  7   7.6   4.2
 20000 -17.8  -0.0  255  11  6   7.2   3.9 | -17.4   0.7  250  12  6   7.6   4.2
 19500 -16.7   1.9  255  11  6   7.2   3.9 | -16.3   2.7  250  12  6   7.6   4.2
 19000 -15.6   3.9  260  11  5   7.2   4.0 | -14.6   5.7  255  11  6   7.6   4.2
 18500 -14.6   5.7  260  10  5   7.0   3.8 | -13.4   7.9  255  11  6   7.5   4.1
 18000 -13.0   8.6  260  10  5   6.9   3.8 | -12.3   9.9  260  11  6   7.5   4.1
 17500 -12.0  10.4  260  10  5   7.1   3.9 | -11.2  11.8  260  11  6   7.6   4.2
 17000 -11.0  12.2  265  10  5   7.2   3.9 | -10.1  13.8  265  11  6   7.6   4.2
 16500  -9.9  14.2  265  10  5   7.2   4.0 |  -8.9  16.0  265  11  6   7.5   4.1
 16000  -8.8  16.2  265  11  5   7.4   4.0 |  -7.9  17.8  265  12  6   7.2   3.9
 15500  -7.7  18.1  265  11  6   7.3   4.0 |  -6.8  19.8  265  12  6   7.2   4.0
 15000  -6.6  20.1  270  11  6   7.9   4.3 |  -5.8  21.6  265  13  7   6.7   3.7
 14500  -5.4  22.3  270  12  6   7.8   4.3 |  -4.8  23.4  265  13  7   6.8   3.7
 14000  -4.2  24.4  270  12  6   8.3   4.5 |  -3.8  25.2  265  13  7   7.3   4.0
 13500  -3.0  26.6  270  12  6   8.3   4.6 |  -2.7  27.1  265  12  6   7.3   4.0
 13000  -1.7  28.9  270  12  6   8.1   4.4 |  -1.6  29.1  265  12  6   7.9   4.4
 12500  -0.5  31.1  270  12  6   8.0   4.4 |  -0.3  31.5  265  11  5   8.2   4.5
 12000   0.7  33.3  270  12  6   7.8   4.3 |   0.9  33.6  265  10  5   8.2   4.5
 11500   1.8  35.2  270  11  6   7.6   4.2 |   2.1  35.8  265   8  4   8.2   4.5
 11000   3.0  37.4  270  10  5   7.6   4.1 |   3.3  37.9  265   7  4   8.4   4.6
 10500   4.1  39.4  270   9  4   7.4   4.1 |   4.6  40.3  265   6  3   8.6   4.7
 10250   4.7  40.5  270   8  4   7.9   4.3 |   5.3  41.5  265   5  3   8.6   4.7
 10000   5.3  41.5  265   8  4   8.1   4.4 |   5.9  42.6  260   5  2   8.5   4.7
  9750   5.9  42.6  265   7  4   7.8   4.3 |   6.5  43.7  260   4  2   8.5   4.6
  9500   6.4  43.5  265   6  3   7.8   4.3 |   7.2  45.0  255   3  2   8.3   4.6
  9250   7.0  44.6  265   6  3   8.1   4.4 |   7.8  46.0  255   3  1   8.9   4.9
  9000   7.6  45.7  270   5  2   7.6   4.2 |   8.5  47.3  255   2  1   9.0   4.9
  8750   8.2  46.8  270   4  2   7.1   3.9 |   9.1  48.4  240   1  1   8.3   4.6
  8500   8.7  47.7  265   3  2   7.0   3.9 |   9.8  49.6  225   1  1   8.6   4.7
  8250   9.2  48.6  265   3  1   7.5   4.1 |  10.4  50.7  195   1  1   8.0   4.4
  8000   9.8  49.6  270   2  1   7.6   4.2 |  11.0  51.8  170   1  1   8.0   4.4
  7750  10.3  50.5  270   2  1   6.2   3.4 |  11.6  52.9  150   1  1   9.2   5.0
  7500  10.7  51.3  260   1  1   5.9   3.3 |  12.3  54.1  140   1  1   9.7   5.3
  7250  11.2  52.2  245   1  0   4.8   2.6 |  13.1  55.6  135   2  1   8.9   4.9
  7000  11.4  52.5  230   1  0   3.5   1.9 |  13.7  56.7  130   2  1   8.4   4.6
  6750  11.6  52.9  215   1  0   1.7   0.9 |  14.3  57.7  125   2  1  10.0   5.5
  6500  11.6  52.9  205   2  1  -1.1  -0.6 |  15.1  59.2  120   2  1  10.9   6.0
  6250  11.4  52.5  205   2  1  -3.5  -1.9 |  15.9  60.6  120   2  1  10.3   5.7
  6000  11.1  52.0  200   2  1  -5.0  -2.7 |  16.7  62.1  120   2  1  10.5   5.8
  5750  10.7  51.3  195   2  1  -4.4  -2.4 |  17.4  63.3  115   2  1   9.6   5.2
  5500  10.4  50.7  200   2  1   1.1   0.6 |  18.2  64.8  115   2  1  14.3   7.9

           04/16/2018 at 1500 MDT          |       04/16/2018 at 1800 MDT
                                           |
CAPE...    +0.2    LI...       +1.1        | CAPE...    +3.5    LI...        0.0
CINH...     0.0    K Index... +14.2        | CINH...    -1.6    K Index... +21.6
                                           |
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 -60.8 -77.4  245  35 18   2.0   1.1 | -60.2 -76.4  245  35 18   1.7   1.0
 45000 -57.9 -72.2  245  42 22   0.4   0.2 | -57.8 -72.0  245  44 23  -0.3  -0.2
 40000 -57.2 -71.0  250  44 23   0.5   0.3 | -58.0 -72.4  245  46 24  -0.2  -0.1
 38000 -55.6 -68.1  250  44 23   3.9   2.1 | -56.3 -69.3  245  46 24   4.6   2.5
 36000 -53.2 -63.8  250  43 22   3.9   2.1 | -53.5 -64.3  245  45 23   4.6   2.5
 34000 -49.6 -57.3  250  41 21   7.9   4.3 | -49.6 -57.3  245  42 22   8.0   4.4
 32000 -44.9 -48.8  245  37 19   7.9   4.3 | -44.8 -48.6  245  39 20   7.9   4.4
 30000 -40.1 -40.2  245  33 17   8.3   4.5 | -40.1 -40.2  245  35 18   7.8   4.3
 29000 -37.6 -35.7  245  32 16   8.3   4.5 | -37.7 -35.9  245  33 17   7.9   4.3
 28000 -35.2 -31.4  245  30 15   8.3   4.5 | -35.4 -31.7  245  30 16   7.9   4.3
 27000 -32.8 -27.0  245  28 14   6.9   3.8 | -33.0 -27.4  245  28 14   7.3   4.0
 26000 -30.7 -23.3  245  26 13   7.1   3.9 | -30.8 -23.4  240  25 13   7.4   4.1
 25000 -28.6 -19.5  240  23 12   7.1   3.9 | -28.6 -19.5  240  23 12   7.4   4.1
 24000 -26.5 -15.7  240  21 11   6.6   3.6 | -26.4 -15.5  240  21 11   7.2   3.9
 23000 -24.5 -12.1  240  19 10   6.4   3.5 | -24.4 -11.9  240  19 10   7.1   3.9
 22000 -22.6  -8.7  235  17  9   6.4   3.5 | -22.3  -8.1  235  17  8   7.1   3.9
 21000 -20.6  -5.1  235  15  8   7.7   4.2 | -20.2  -4.4  235  14  7   6.9   3.8
 20000 -18.4  -1.1  235  14  7   7.6   4.2 | -18.1  -0.6  235  12  6   6.9   3.8
 19500 -17.2   1.0  235  14  7   7.6   4.2 | -17.1   1.2  230  11  6   6.9   3.8
 19000 -15.5   4.1  235  13  7   7.6   4.2 | -16.1   3.0  230  11  5   6.9   3.8
 18500 -14.4   6.1  235  13  7   7.2   4.0 | -14.6   5.7  230   9  5   7.4   4.1
 18000 -13.4   7.9  235  13  7   7.2   4.0 | -13.5   7.7  230   9  4   7.4   4.1
 17500 -12.3   9.9  235  12  6   8.2   4.5 | -12.4   9.7  230   8  4   7.4   4.0
 17000 -11.0  12.2  235  12  6   8.4   4.6 | -11.3  11.7  230   8  4   7.4   4.0
 16500  -9.8  14.4  235  11  6   8.6   4.7 | -10.2  13.6  235   7  4   7.6   4.2
 16000  -8.4  16.9  235  10  5   9.2   5.0 |  -9.0  15.8  235   7  3   8.4   4.6
 15500  -7.1  19.2  230  10  5   9.1   5.0 |  -7.8  18.0  235   6  3   8.3   4.5
 15000  -5.7  21.7  230   9  5   9.1   5.0 |  -6.4  20.5  235   6  3   9.4   5.2
 14500  -4.3  24.3  230   9  5   9.1   5.0 |  -5.0  23.0  240   6  3   9.3   5.1
 14000  -3.0  26.6  225   8  4   9.2   5.0 |  -3.6  25.5  240   6  3   9.6   5.3
 13500  -1.6  29.1  225   8  4   9.2   5.0 |  -2.2  28.0  240   5  3   9.7   5.3
 13000  -0.2  31.6  220   7  4   9.1   5.0 |  -0.7  30.7  240   5  3   9.7   5.3
 12500   1.1  34.0  220   6  3   9.1   5.0 |   0.7  33.3  240   5  3   9.8   5.4
 12000   2.5  36.5  215   5  3   9.1   5.0 |   2.2  36.0  240   5  3   9.8   5.3
 11500   3.8  38.8  210   5  2   9.0   5.0 |   3.6  38.5  245   5  2   9.7   5.3
 11000   5.2  41.4  205   4  2   8.7   4.7 |   5.1  41.2  245   5  2   9.0   4.9
 10500   6.4  43.5  195   3  2   7.7   4.2 |   6.4  43.5  250   4  2   7.6   4.2
 10250   7.1  44.8  190   3  1  10.9   6.0 |   7.0  44.6  250   4  2  11.2   6.1
 10000   8.0  46.4  195   2  1  11.9   6.5 |   8.0  46.4  250   4  2  12.4   6.8
  9750   8.8  47.8  190   2  1   9.3   5.1 |   8.7  47.7  255   4  2   9.5   5.2
  9500   9.5  49.1  185   2  1  10.2   5.6 |   9.5  49.1  255   4  2  10.7   5.9
  9250  10.2  50.4  180   2  1   9.1   5.0 |  10.3  50.5  260   3  2   8.7   4.8
  9000  10.9  51.6  185   2  1   9.1   5.0 |  10.9  51.6  255   4  2   8.7   4.8
  8750  11.6  52.9  180   2  1   9.9   5.5 |  11.6  52.9  260   4  2  10.3   5.6
  8500  12.3  54.1  180   2  1   9.9   5.4 |  12.4  54.3  260   4  2  10.0   5.5
  8250  13.1  55.6  175   1  1   9.3   5.1 |  13.1  55.6  260   4  2   9.6   5.3
  8000  13.8  56.8  165   1  1   9.1   5.0 |  13.8  56.8  265   3  2   9.3   5.1
  7750  14.5  58.1  160   1  1  10.1   5.5 |  14.5  58.1  270   3  2  10.0   5.5
  7500  15.2  59.4  160   1  1  10.5   5.7 |  15.3  59.5  270   3  2  10.3   5.7
  7250  16.0  60.8  160   1  1   9.8   5.4 |  16.0  60.8  270   3  2   9.8   5.4
  7000  16.7  62.1  150   1  0   9.1   5.0 |  16.8  62.2  270   3  2   9.3   5.1
  6750  17.4  63.3  140   1  0  10.3   5.6 |  17.5  63.5  275   3  1  10.0   5.5
  6500  18.2  64.8  140   1  0  11.0   6.0 |  18.2  64.8  275   3  2  10.5   5.8
  6250  19.0  66.2  140   1  0  10.5   5.7 |  19.0  66.2  275   3  2  10.2   5.6
  6000  19.8  67.6  125   1  0  10.7   5.8 |  19.8  67.6  275   3  1  10.4   5.7
  5750  20.6  69.1  115   1  0   9.2   5.0 |  20.5  68.9  280   2  1   9.1   5.0
  5500  21.3  70.3  120   1  0  13.2   7.2 |  21.1  70.0  280   3  1   7.9   4.3
________________________________________________________________________________

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 old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 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.

CINH (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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