Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 231250
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0650 MDT Monday, March 23, 2015

This forecast is for Monday, March 23, 2015:

If the trigger temperature of 59.6 F/15.3 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 568 ft/min (2.9 m/s)
   Maximum height of thermals.................. 16185 ft MSL (10878 ft AGL)

Forecast maximum temperature................... 68.0 F/20.5 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 10815 ft MSL (5508 ft AGL)
Thermal soaring outlook for Tuesday 03/24...... Good

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... Some improvement
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 39007 ft MSL (33700 ft AGL)
Wave soaring outlook for Tuesday 03/24......... Excellent

Remarks... Increasing moisture aloft through this afternoon as an upper level
           disturbance approaches the state from the northwest.

Sunrise/Sunset.................... 06:58:20 / 19:13:20 MDT
Total possible sunshine........... 12 hr 14 min 59 sec (734 min 59 sec)
Altitude of sun at 13:06:01 MDT... 51.37 degrees

Upper air data from numerical model forecast valid on 03/23/2015 at 0600 MDT

Freezing level.................. 10975 ft MSL (5668 ft AGL)
Convective condensation level... 14173 ft MSL (8866 ft AGL)
Lifted condensation level....... 14571 ft MSL (9264 ft AGL)
Lifted index.................... -0.5
K index......................... +16.8

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  -58.6 -73.5   270   30   16   1.7   0.9      M     M       M      M    M
 45000  -55.9 -68.6   270   43   22  -1.2  -0.6      M     M       M      M    M
 40000  -61.1 -78.0   265   68   35  -3.4  -1.9      M     M       M      M    M
 38000  -60.6 -77.1   265   71   37   5.2   2.9      M     M       M      M    M
 36000  -57.4 -71.3   265   68   35   5.2   2.9      M     M       M      M    M
 34000  -54.0 -65.2   260   65   33   8.0   4.4      M     M       M      M    M
 32000  -49.4 -56.9   260   59   31   7.8   4.3      M     M       M      M    M
 30000  -44.1 -47.4   265   54   28   8.1   4.5   31.3  88.4     8.5      M    M
 29000  -41.6 -42.9   265   52   27   8.1   4.5   30.6  87.1     8.1      M    M
 28000  -39.2 -38.6   265   51   26   8.1   4.5   30.0  86.0     7.7      M    M
 27000  -36.8 -34.2   270   49   25   8.4   4.6   29.5  85.1     7.4      M    M
 26000  -34.3 -29.7   270   47   24   8.4   4.6   28.9  84.0     7.0      M    M
 25000  -31.7 -25.1   270   45   23   8.4   4.6   28.4  83.1     6.7      M    M
 24000  -29.2 -20.6   270   42   22   7.6   4.2   28.0  82.5     6.4      M    M
 23000  -27.2 -17.0   270   39   20   6.8   3.7   26.8  80.3     5.5      M    M
 22000  -25.2 -13.4   270   36   19   6.8   3.7   25.8  78.4     4.7      M    M
 21000  -23.2  -9.8   270   34   17   5.9   3.2   24.7  76.5     3.9      M    M
 20000  -21.5  -6.7   265   33   17   5.8   3.2   23.3  73.9     2.7      M    M
 19500  -20.6  -5.1   260   32   17   5.8   3.2   22.6  72.7     2.1      M    M
 19000  -19.7  -3.5   260   32   16   5.8   3.2   21.9  71.5     1.5      M    M
 18500  -18.8  -1.8   260   31   16   7.4   4.1   21.4  70.5     1.0      M    M
 18000  -17.6   0.3   260   31   16   8.1   4.4   21.1  69.9     0.8      M    M
 17500  -16.4   2.5   260   31   16   8.2   4.5   20.8  69.4     0.5      M    M
 17000  -15.1   4.8   260   30   15   8.9   4.9   20.6  69.1     0.3      M    M
 16500  -13.8   7.2   260   27   14   8.9   4.9   20.4  68.8     0.2      M    M
 16000  -11.9  10.6   260   25   13   8.6   4.7   20.2  68.3    -0.1    936  4.8
 15500  -10.6  12.9   255   24   12   8.7   4.7   20.0  68.0    -0.3    882  4.5
 15000   -9.3  15.3   255   23   12   8.9   4.9   19.8  67.7    -0.5    829  4.2
 14500   -8.0  17.6   250   23   12   8.9   4.9   19.7  67.4    -0.6    774  3.9
 14000   -6.7  19.9   250   24   12   8.3   4.6   19.5  67.1    -0.8    721  3.7
 13500   -5.5  22.1   245   23   12   8.4   4.6   19.3  66.7    -1.0    669  3.4
 13000   -4.3  24.3   245   23   12   7.7   4.2   19.0  66.2    -1.3    618  3.1
 12500   -3.2  26.2   240   21   11   7.5   4.1   18.6  65.5    -1.6    570  2.9
 12000   -2.1  28.2   235   20   10   7.3   4.0   18.3  64.9    -2.0    522  2.7
 11500   -1.0  30.2   230   18    9   7.2   3.9   17.8  64.1    -2.4    476  2.4
 11000    0.0  32.0   225   17    9   7.2   3.9   17.4  63.4    -2.9    430  2.2
 10500    1.0  33.8   215   16    8   7.8   4.3   17.0  62.6    -3.3    385  2.0
 10250    1.6  34.9   215   16    8   4.8   2.6   16.8  62.3    -3.5    362  1.8
 10000    1.8  35.2   210   16    8   5.3   2.9   16.3  61.4    -4.0    347  1.8
  9750    2.4  36.3   205   17    9   8.6   4.7   16.2  61.1    -4.2    322  1.6
  9500    3.0  37.4   200   18    9   8.1   4.4   16.0  60.9    -4.4    297  1.5
  9250    3.5  38.3   195   19   10   7.0   3.8   15.9  60.6    -4.5    273  1.4
  9000    4.0  39.2   195   20   10   5.9   3.2   15.6  60.1    -4.8    252  1.3
  8750    4.5  40.1   195   21   11   6.7   3.7   15.4  59.6    -5.1    231  1.2
  8500    5.0  41.0   195   22   11   7.0   3.9   15.1  59.2    -5.3    208  1.1
  8250    5.5  41.9   190   23   12   6.2   3.4   14.9  58.8    -5.6    186  0.9
  8000    5.9  42.6   190   24   12   5.6   3.1   14.6  58.3    -5.9    165  0.8
  7750    6.3  43.3   190   25   13   6.5   3.6   14.3  57.8    -6.2    145  0.7
  7500    6.8  44.2   190   25   13   6.7   3.7   14.1  57.3    -6.4    122  0.6
  7250    7.3  45.1   190   25   13   6.3   3.4   13.8  56.9    -6.7    101  0.5
  7000    7.8  46.0   190   26   13   5.7   3.2   13.5  56.4    -7.0     80  0.4
  6750    8.2  46.8   190   26   14   6.9   3.8   13.3  55.9    -7.3     59  0.3
  6500    8.6  47.5   190   26   14   1.4   0.7   12.9  55.3    -7.6     39  0.2
  6250    8.4  47.1   185   24   13  -4.6  -2.5   12.0  53.5    -8.6     40  0.2
  6000    8.1  46.6   185   23   12  -2.1  -1.2   11.0  51.8    -9.7     41  0.2
  5750    7.8  46.0   180   21   11  -7.3  -4.0   10.0  50.0   -10.7     43  0.2
  5500    6.7  44.1   175   16    8 -19.4 -10.6    8.3  46.9   -12.6     68  0.3

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

           03/23/2015 at 0900 MDT          |       03/23/2015 at 1200 MDT
                                           |
K index... +16.5  LI... +273.3             | K index... +15.9  LI... +272.7
CAPE... 0.0  CIN... M                      | CAPE... +16.5  CIN... -95.0
                                           |
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 -57.9 -72.2  270  31 16   2.0   1.1 | -56.7 -70.1  265  32 16   2.6   1.5
 45000 -54.8 -66.6  260  46 24  -0.8  -0.4 | -52.5 -62.5  255  51 26  -0.2  -0.1
 40000 -59.5 -75.1  260  63 33  -3.1  -1.7 | -58.6 -73.5  250  69 35  -4.1  -2.2
 38000 -59.5 -75.1  260  67 34   3.3   1.8 | -59.2 -74.6  250  71 37   3.1   1.7
 36000 -57.5 -71.5  255  66 34   3.3   1.8 | -57.3 -71.1  250  66 34   3.1   1.7
 34000 -55.1 -67.2  255  65 34   8.3   4.5 | -55.2 -67.4  250  61 31   7.6   4.2
 32000 -50.5 -58.9  255  60 31   7.8   4.3 | -50.0 -58.0  250  57 29   7.7   4.2
 30000 -44.9 -48.8  250  55 28   9.6   5.3 | -45.3 -49.5  250  54 28   8.0   4.4
 29000 -42.0 -43.6  255  54 28   9.6   5.3 | -42.9 -45.2  250  52 27   8.1   4.4
 28000 -39.1 -38.4  255  52 27   9.6   5.3 | -40.5 -40.9  255  50 26   8.1   4.4
 27000 -36.3 -33.3  255  50 26   8.3   4.5 | -38.0 -36.4  255  48 25   7.9   4.4
 26000 -34.0 -29.2  250  49 25   7.8   4.3 | -35.7 -32.3  255  46 24   7.8   4.3
 25000 -31.7 -25.1  250  48 25   7.8   4.3 | -33.4 -28.1  250  44 22   7.8   4.3
 24000 -29.3 -20.7  245  46 24   6.9   3.8 | -31.0 -23.8  250  41 21   7.9   4.3
 23000 -27.7 -17.9  245  43 22   5.5   3.0 | -28.6 -19.5  255  40 21   8.3   4.5
 22000 -26.0 -14.8  240  39 20   5.5   3.0 | -26.1 -15.0  255  39 20   8.3   4.6
 21000 -24.3 -11.7  235  35 18   6.6   3.6 | -23.7 -10.7  255  38 20   7.0   3.8
 20000 -22.3  -8.1  240  30 15   6.9   3.8 | -21.8  -7.2  250  34 17   6.4   3.5
 19500 -21.3  -6.3  240  27 14   6.9   3.8 | -20.8  -5.4  250  31 16   6.4   3.5
 19000 -20.3  -4.5  240  25 13   7.0   3.8 | -19.9  -3.8  245  29 15   6.4   3.5
 18500 -19.2  -2.6  245  22 12   8.1   4.5 | -18.9  -2.0  245  27 14   7.2   4.0
 18000 -17.9  -0.2  245  23 12   8.8   4.8 | -17.7   0.1  245  27 14   8.1   4.4
 17500 -16.6   2.1  250  23 12   8.8   4.9 | -16.5   2.3  250  27 14   8.2   4.5
 17000 -15.3   4.5  250  24 12   9.2   5.0 | -15.4   4.3  250  28 15   7.4   4.1
 16500 -13.9   7.0  250  24 12   9.2   5.0 | -13.7   7.3  255  31 16   7.6   4.2
 16000 -11.9  10.6  255  25 13   8.6   4.7 | -12.6   9.3  255  30 15   7.6   4.2
 15500 -10.7  12.7  255  26 13   8.6   4.7 | -11.5  11.3  250  28 14   7.5   4.1
 15000  -9.4  15.1  255  26 13   8.5   4.7 | -10.2  13.6  245  26 13   9.3   5.1
 14500  -8.2  17.2  255  24 13   8.5   4.7 |  -8.9  16.0  245  25 13   9.3   5.1
 14000  -6.9  19.6  255  24 12   8.6   4.7 |  -7.6  18.3  245  24 12   8.9   4.9
 13500  -5.6  21.9  255  23 12   8.6   4.7 |  -6.3  20.7  245  22 11   8.9   4.9
 13000  -4.3  24.3  250  23 12   8.8   4.8 |  -5.0  23.0  240  20 10   8.4   4.6
 12500  -3.0  26.6  250  22 11   8.8   4.8 |  -3.8  25.2  245  18  9   8.2   4.5
 12000  -1.7  28.9  245  21 11   8.9   4.9 |  -2.6  27.3  245  16  8   8.4   4.6
 11500  -0.3  31.5  245  20 10   9.0   5.0 |  -1.3  29.7  250  13  7   8.6   4.7
 11000   1.0  33.8  240  19 10   8.0   4.4 |  -0.0  32.0  260  11  6   8.3   4.5
 10500   2.1  35.8  235  18  9   8.2   4.5 |   1.2  34.2  265  10  5   7.3   4.0
 10250   2.6  36.7  230  18  9   4.8   2.7 |   1.8  35.2  265  10  5  11.1   6.1
 10000   2.9  37.2  230  18  9   4.8   2.6 |   2.8  37.0  270  10  5  11.5   6.3
  9750   3.4  38.1  230  18  9   8.0   4.4 |   3.4  38.1  270   9  5   7.9   4.4
  9500   4.0  39.2  225  18  9   7.4   4.0 |   4.1  39.4  275   9  5   9.2   5.0
  9250   4.5  40.1  225  17  9   6.9   3.8 |   4.7  40.5  275   9  5   7.8   4.3
  9000   4.9  40.8  220  18  9   5.2   2.9 |   5.2  41.4  275   8  4   6.2   3.4
  8750   5.3  41.5  220  18  9   5.0   2.8 |   5.7  42.3  275   8  4   6.2   3.4
  8500   5.7  42.3  215  19 10   4.9   2.7 |   6.2  43.2  275   8  4   6.7   3.7
  8250   6.0  42.8  210  20 10   5.8   3.2 |   6.6  43.9  275   9  4   5.9   3.3
  8000   6.5  43.7  205  21 11   6.8   3.7 |   7.0  44.6  265   8  4   4.4   2.4
  7750   7.0  44.6  205  23 12   5.6   3.1 |   7.3  45.1  245   8  4   3.7   2.0
  7500   7.4  45.3  205  24 12   5.0   2.8 |   7.5  45.5  230   8  4   2.9   1.6
  7250   7.7  45.9  200  25 13   4.1   2.3 |   7.7  45.9  210   9  5   6.6   3.6
  7000   8.0  46.4  200  26 13   3.2   1.8 |   8.4  47.1  200  10  5   9.9   5.4
  6750   8.2  46.8  200  26 13   3.6   1.9 |   9.0  48.2  190  10  5   8.6   4.7
  6500   8.4  47.1  195  27 14  -0.4  -0.2 |   9.6  49.3  185  10  5   9.4   5.1
  6250   8.1  46.6  195  25 13  -4.8  -2.7 |  10.4  50.7  185  10  5  10.8   5.9
  6000   7.7  45.9  190  22 11  -5.0  -2.7 |  11.2  52.2  185  10  5  11.2   6.2
  5750   7.2  45.0  185  20 10  -5.4  -3.0 |  12.0  53.6  185  10  5  10.4   5.7
  5500   6.8  44.2  175  15  8  -0.8  -0.4 |  12.9  55.2  185   9  5  14.6   8.0

           03/23/2015 at 1500 MDT          |       03/23/2015 at 1800 MDT
                                           |
K index... +21.3  LI... +271.3             | K index... +14.5  LI... +272.0
CAPE... +186.0  CIN... -20.5               | CAPE... +187.7  CIN... -31.1
                                           |
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 -57.8 -72.0  260  25 13   2.6   1.4 | -57.5 -71.5  265  29 15   3.1   1.7
 45000 -53.6 -64.5  255  37 19   1.1   0.6 | -52.6 -62.7  265  43 22   1.8   1.0
 40000 -56.6 -69.9  250  64 33  -2.0  -1.1 | -55.5 -67.9  260  58 30  -2.0  -1.1
 38000 -57.0 -70.6  250  70 36   1.1   0.6 | -56.2 -69.2  260  62 32   0.5   0.3
 36000 -56.4 -69.5  255  69 35   1.1   0.6 | -55.9 -68.6  265  64 33   0.5   0.3
 34000 -55.5 -67.9  260  68 35   5.7   3.1 | -55.5 -67.9  265  66 34   4.1   2.3
 32000 -50.7 -59.3  260  72 37   7.2   3.9 | -51.7 -61.1  270  68 35   6.2   3.4
 30000 -46.3 -51.3  265  75 38   8.1   4.5 | -47.4 -53.3  270  69 35   8.1   4.4
 29000 -43.8 -46.8  265  72 37   8.1   4.5 | -45.0 -49.0  270  67 34   8.0   4.4
 28000 -41.4 -42.5  265  70 36   8.1   4.5 | -42.5 -44.5  270  65 33   8.0   4.4
 27000 -38.9 -38.0  270  68 35   8.1   4.4 | -40.1 -40.2  270  62 32   8.2   4.5
 26000 -36.5 -33.7  270  63 32   8.1   4.4 | -37.6 -35.7  270  58 30   8.5   4.7
 25000 -34.1 -29.4  270  57 30   8.1   4.4 | -35.1 -31.2  270  53 27   8.5   4.7
 24000 -31.7 -25.1  270  52 27   8.0   4.4 | -32.5 -26.5  270  48 24   8.5   4.7
 23000 -29.3 -20.7  270  49 25   8.0   4.4 | -29.9 -21.8  270  45 23   8.8   4.8
 22000 -26.9 -16.4  270  45 23   8.0   4.4 | -27.3 -17.1  270  44 23   8.8   4.8
 21000 -24.5 -12.1  265  42 22   7.6   4.2 | -24.6 -12.3  270  42 22   8.3   4.5
 20000 -22.3  -8.1  265  41 21   7.4   4.1 | -22.3  -8.1  265  40 21   7.8   4.3
 19500 -21.2  -6.2  265  40 21   7.4   4.1 | -21.1  -6.0  265  39 20   7.8   4.3
 19000 -20.1  -4.2  265  39 20   7.5   4.1 | -20.0  -4.0  260  38 20   7.9   4.3
 18500 -19.0  -2.2  260  39 20   7.6   4.2 | -18.8  -1.8  260  38 19   7.8   4.3
 18000 -17.9  -0.2  260  37 19   7.7   4.2 | -17.6   0.3  260  38 19   7.8   4.3
 17500 -16.8   1.8  260  35 18   7.8   4.3 | -16.5   2.3  260  38 20   7.8   4.3
 17000 -15.7   3.7  260  34 17   7.4   4.1 | -15.3   4.5  265  38 20   7.9   4.3
 16500 -14.0   6.8  260  32 16   7.5   4.1 | -14.2   6.4  265  38 19   7.9   4.3
 16000 -12.8   9.0  260  30 15   8.9   4.9 | -12.4   9.7  265  36 19   8.2   4.5
 15500 -11.5  11.3  260  28 14   8.7   4.8 | -11.2  11.8  265  34 18   8.1   4.5
 15000 -10.2  13.6  260  26 13   9.2   5.0 |  -9.9  14.2  265  32 17   8.9   4.9
 14500  -8.9  16.0  260  24 13   9.2   5.0 |  -8.6  16.5  265  30 16   8.9   4.9
 14000  -7.5  18.5  260  23 12   8.8   4.9 |  -7.3  18.9  265  28 14   9.4   5.1
 13500  -6.2  20.8  260  21 11   8.7   4.8 |  -5.9  21.4  265  27 14   9.5   5.2
 13000  -4.9  23.2  260  18  9   8.8   4.8 |  -4.4  24.1  265  26 13   9.4   5.2
 12500  -3.6  25.5  260  17  9   8.8   4.8 |  -3.0  26.6  265  24 13   9.3   5.1
 12000  -2.3  27.9  260  15  8   8.7   4.8 |  -1.7  28.9  265  23 12   9.3   5.1
 11500  -1.1  30.0  255  13  7   8.6   4.7 |  -0.3  31.5  265  21 11   9.2   5.1
 11000   0.2  32.4  250  11  5   8.2   4.5 |   1.1  34.0  265  20 10   8.8   4.8
 10500   1.4  34.5  250   9  5   7.3   4.0 |   2.3  36.1  265  18  9   7.6   4.1
 10250   2.0  35.6  250   8  4  10.2   5.6 |   2.9  37.2  270  17  9  10.2   5.6
 10000   2.8  37.0  250   7  4  10.2   5.6 |   3.8  38.8  270  16  8  10.7   5.8
  9750   3.4  38.1  255   6  3   7.3   4.0 |   4.4  39.9  270  15  8   8.1   4.5
  9500   4.0  39.2  255   5  2   8.2   4.5 |   5.0  41.0  270  14  7   8.4   4.6
  9250   4.6  40.3  260   4  2   7.8   4.3 |   5.6  42.1  270  13  6   8.9   4.9
  9000   5.2  41.4  265   3  2   8.4   4.6 |   6.3  43.3  265  11  6   8.6   4.7
  8750   5.8  42.4  275   2  1   9.0   4.9 |   6.9  44.4  270  10  5   7.8   4.3
  8500   6.4  43.5  290   2  1   8.6   4.7 |   7.5  45.5  270   9  4   7.9   4.3
  8250   7.0  44.6  305   2  1   9.7   5.3 |   8.1  46.6  270   7  4   8.3   4.5
  8000   7.8  46.0  315   2  1  10.8   5.9 |   8.7  47.7  270   6  3   9.0   5.0
  7750   8.6  47.5  320   2  1   9.7   5.3 |   9.3  48.7  270   6  3   8.8   4.8
  7500   9.3  48.7  320   2  1   8.8   4.8 |   9.9  49.8  270   5  3   8.2   4.5
  7250   9.9  49.8  320   2  1  10.0   5.5 |  10.5  50.9  275   5  2   9.4   5.2
  7000  10.7  51.3  320   2  1  11.0   6.1 |  11.2  52.2  275   4  2  10.8   5.9
  6750  11.5  52.7  320   2  1   9.8   5.4 |  12.0  53.6  275   4  2   9.5   5.2
  6500  12.2  54.0  320   3  1   9.5   5.2 |  12.7  54.9  275   4  2   8.7   4.8
  6250  13.0  55.4  325   3  1  10.5   5.8 |  13.4  56.1  275   4  2   9.9   5.4
  6000  13.8  56.8  325   3  1  11.3   6.2 |  14.1  57.4  275   4  2  10.8   5.9
  5750  14.6  58.3  325   3  1   9.8   5.4 |  14.9  58.8  275   4  2   9.3   5.1
  5500  15.4  59.7  325   3  1  13.4   7.3 |  15.5  59.9  275   4  2   8.4   4.6
________________________________________________________________________________

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.

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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