Soaring Guidance
Issued by NWS Denver/Boulder, CO

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493
UXUS97 KBOU 131330
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0629 MST Saturday, February 13, 2016

This forecast is for Saturday, February 13, 2016:

If the trigger temperature of 67.3 F/19.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6669 ft MSL (1384 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6467 ft MSL (1181 ft AGL)
Thermal soaring outlook for Sunday 02/14....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Improving
Height of stable layer (12-18K ft MSL)......... 13640 ft MSL (8355 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 14131 ft MSL (8846 ft AGL)
Wave soaring outlook for Sunday 02/14.......... Good

Remarks... Moderate westerly flow aloft this morning will be increasing this
           afternoon.

Sunrise/Sunset.................... 06:54:47 / 17:31:41 MST
Total possible sunshine........... 10 hr 36 min 54 sec (636 min 54 sec)
Altitude of sun at 12:13:33 MST... 36.92 degrees

Upper air data from rawinsonde observation taken on 02/13/2016 at 0500 MST

Freezing level.................. 5962 ft MSL (677 ft AGL)
Additional freezing level....... 12085 ft MSL (6800 ft AGL)
Convective condensation level... 19061 ft MSL (13776 ft AGL)
Lifted condensation level....... 15965 ft MSL (10680 ft AGL)
Lifted index.................... +5.1
K index......................... -14.4

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  -61.6 -78.9   290   57   29   3.2   1.8   96.8 206.3    45.2      M    M
 45000  -56.4 -69.5   285   80   41   4.5   2.5   80.9 177.7    38.7      M    M
 40000  -62.2 -80.0   280   77   40  -1.0  -0.6   47.7 117.9    19.7      M    M
 38000  -62.8 -81.0   280   72   37   6.4   3.5   37.9 100.2    13.6      M    M
 36000  -58.6 -73.5   275   67   35   8.2   4.5   35.5  95.9    12.3      M    M
 34000  -53.6 -64.5   275   62   32   8.5   4.6   34.3  93.7    11.8      M    M
 32000  -48.5 -55.3   275   57   29   9.2   5.1   33.4  92.1    11.4      M    M
 30000  -43.4 -46.1   270   51   26   7.5   4.1   32.5  90.5    11.1      M    M
 29000  -41.1 -42.0   270   47   24   7.5   4.1   31.5  88.8    10.5      M    M
 28000  -38.1 -36.6   275   41   21   9.2   5.0   30.8  87.4    10.0      M    M
 27000  -35.4 -31.7   275   36   19   8.8   4.8   30.4  86.7     9.8      M    M
 26000  -32.8 -27.0   275   31   16   8.8   4.8   30.0  86.0     9.7      M    M
 25000  -30.1 -22.2   280   27   14   9.0   4.9   29.7  85.5     9.5      M    M
 24000  -27.5 -17.5   280   23   12   8.1   4.4   29.3  84.8     9.3      M    M
 23000  -25.1 -13.2   280   24   12   8.2   4.5   28.7  83.6     8.9      M    M
 22000  -22.6  -8.7   280   25   13   8.2   4.5   28.1  82.6     8.5      M    M
 21000  -20.4  -4.7   280   26   13   6.2   3.4   27.5  81.4     8.1      M    M
 20000  -18.1  -0.6   295   28   14   8.9   4.9   26.8  80.2     7.5      M    M
 19500  -16.7   1.9   295   28   15   9.1   5.0   26.6  79.9     7.5      M    M
 19000  -15.4   4.3   300   29   15  10.5   5.8   26.5  79.7     7.4      M    M
 18500  -14.0   6.8   295   33   17   7.1   3.9   26.4  79.6     7.4      M    M
 18000  -12.8   9.0   295   34   17   7.8   4.3   26.1  78.9     7.2      M    M
 17500  -11.6  11.1   295   34   17   8.1   4.5   25.8  78.4     6.9      M    M
 17000  -10.3  13.5   295   34   18   8.1   4.5   25.5  77.9     6.7      M    M
 16500   -9.1  15.6   295   35   18   8.1   4.4   25.2  77.4     6.5      M    M
 16000   -7.9  17.8   295   35   18   7.2   3.9   25.0  77.0     6.4      M    M
 15500   -6.9  19.6   295   36   19   6.4   3.5   24.4  75.9     5.9      M    M
 15000   -6.0  21.2   290   38   19   6.3   3.5   23.8  74.8     5.4      M    M
 14500   -5.0  23.0   290   39   20   6.4   3.5   23.2  73.8     4.9      M    M
 14000   -3.6  25.5   285   41   21   4.2   2.3   22.4  72.4     4.2      M    M
 13500   -3.3  26.1   285   41   21   5.3   2.9   21.3  70.3     3.1      M    M
 13000   -2.2  28.0   285   40   21   8.4   4.6   20.9  69.6     2.7      M    M
 12500   -0.9  30.4   280   37   19   8.8   4.8   20.8  69.4     2.6      M    M
 12000    0.4  32.7   280   34   17   8.8   4.8   20.6  69.1     2.5      M    M
 11500    1.7  35.1   280   30   16   8.8   4.8   20.4  68.8     2.3      M    M
 11000    3.1  37.6   280   27   14   8.8   4.9   20.3  68.5     2.2      M    M
 10500    4.4  39.9   280   24   13   8.8   4.9   20.1  68.3     2.0      M    M
 10250    5.0  41.0   280   23   12   8.9   4.9   20.1  68.2     2.0      M    M
 10000    5.7  42.3   280   22   11   9.0   4.9   20.0  68.0     1.9      M    M
  9750    6.3  43.3   280   21   11   9.0   4.9   20.0  67.9     1.8      M    M
  9500    7.0  44.6   285   21   11   9.0   4.9   19.9  67.8     1.8      M    M
  9250    7.7  45.9   285   20   10   9.0   4.9   19.9  67.8     1.7      M    M
  9000    8.3  46.9   285   19   10   9.0   4.9   19.8  67.7     1.7      M    M
  8750    9.0  48.2   280   19   10   9.0   4.9   19.7  67.5     1.6      M    M
  8500    9.6  49.3   280   18    9   9.0   4.9   19.7  67.4     1.5      M    M
  8250   10.3  50.5   275   18    9   9.0   4.9   19.6  67.3     1.5      M    M
  8000   11.0  51.8   275   18    9   9.0   4.9   19.6  67.2     1.4      M    M
  7750   11.6  52.9   275   18    9   9.1   5.0   19.5  67.1     1.3      M    M
  7500   12.3  54.1   280   18   10   8.8   4.8   19.4  67.0     1.3      M    M
  7250   12.9  55.2   280   19   10  10.1   5.5   19.4  66.9     1.2      M    M
  7000   13.6  56.5   280   19   10   5.2   2.8   19.3  66.8     1.1      M    M
  6750   13.9  57.0   270   15    8  10.8   5.9   18.9  66.1     0.7      M    M
  6500   12.7  54.9   255   12    6 -76.6 -42.0   17.1  62.8    -1.2     37  0.2
  6250    4.2  39.6   235   10    5 -88.3 -48.5    7.8  46.0   -10.5    287  1.5
  6000    0.9  33.6   205   10    5 -37.8 -20.8    3.8  38.9   -14.6    378  1.9
  5750   -2.7  27.1   205    6    3 -37.5 -20.6   -0.7  30.8   -18.9    479  2.4
  5500   -2.3  27.9   200    1    1  55.1  30.2   -1.0  30.3   -19.3    458  2.3

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

           02/13/2016 at 0800 MST          |       02/13/2016 at 1100 MST
                                           |
K index... -14.8  LI... +3.3               | K index... -23.9  LI... +3.4
CAPE... 0.0  CIN... -0.6                   | CAPE... 0.0  CIN... -0.6
                                           |
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 -59.5 -75.1  285  49 25   0.7   0.4 | -58.9 -74.0  270  43 22  -0.1  -0.0
 45000 -58.5 -73.3  280  87 45  -1.8  -1.0 | -59.0 -74.2  275  86 44  -1.6  -0.9
 40000 -64.9 -84.8  280  74 38  -4.3  -2.4 | -64.3 -83.7  275  77 40  -3.6  -2.0
 38000 -63.5 -82.3  275  70 36   7.9   4.3 | -62.9 -81.2  275  73 37   7.2   3.9
 36000 -58.7 -73.7  275  66 34   7.9   4.3 | -58.6 -73.5  275  68 35   7.2   3.9
 34000 -53.3 -63.9  280  62 32   8.2   4.5 | -54.1 -65.4  270  64 33   8.2   4.5
 32000 -48.4 -55.1  280  58 30   8.2   4.5 | -48.6 -55.5  270  60 31   8.3   4.5
 30000 -43.4 -46.1  280  54 28   8.2   4.5 | -43.5 -46.3  270  57 29   8.5   4.7
 29000 -41.0 -41.8  280  51 26   8.2   4.5 | -41.0 -41.8  270  55 28   8.5   4.7
 28000 -38.5 -37.3  280  49 25   8.2   4.5 | -38.4 -37.1  270  53 27   8.5   4.7
 27000 -36.0 -32.8  280  46 24   8.4   4.6 | -35.9 -32.6  270  51 26   8.3   4.6
 26000 -33.5 -28.3  280  43 22   8.4   4.6 | -33.4 -28.1  270  48 25   8.4   4.6
 25000 -31.0 -23.8  280  40 21   8.4   4.6 | -30.9 -23.6  270  45 23   8.4   4.6
 24000 -28.5 -19.3  280  38 19   8.2   4.5 | -28.4 -19.1  270  42 22   7.6   4.2
 23000 -26.0 -14.8  280  34 18   8.2   4.5 | -26.2 -15.2  270  38 19   7.5   4.1
 22000 -23.6 -10.5  280  31 16   8.2   4.5 | -23.9 -11.0  270  34 17   7.5   4.1
 21000 -21.1  -6.0  275  28 14   7.9   4.3 | -21.6  -6.9  270  30 15   8.1   4.4
 20000 -18.8  -1.8  275  25 13   7.9   4.3 | -19.2  -2.6  270  25 13   8.0   4.4
 19500 -17.6   0.3  275  23 12   7.9   4.3 | -18.0  -0.4  265  23 12   8.0   4.4
 19000 -16.4   2.5  270  22 11   7.9   4.3 | -16.8   1.8  265  21 11   8.0   4.4
 18500 -15.2   4.6  270  20 10   7.9   4.3 | -15.5   4.1  265  19 10   8.7   4.8
 18000 -14.0   6.8  270  19 10   7.9   4.3 | -14.2   6.4  270  17  9   8.8   4.8
 17500 -12.2  10.0  275  17  9   8.0   4.4 | -12.9   8.8  270  16  8   9.0   4.9
 17000 -11.0  12.2  275  16  8   8.0   4.4 | -10.8  12.6  275  15  8   9.3   5.1
 16500  -9.8  14.4  280  15  8   8.4   4.6 |  -9.4  15.1  280  15  8   8.7   4.8
 16000  -8.5  16.7  285  16  8   8.7   4.8 |  -8.2  17.2  285  16  8   8.3   4.5
 15500  -7.2  19.0  290  16  8   8.6   4.7 |  -6.9  19.6  290  18  9   8.2   4.5
 15000  -6.0  21.2  290  17  9   8.2   4.5 |  -5.8  21.6  295  19 10   7.7   4.2
 14500  -4.7  23.5  295  18  9   8.2   4.5 |  -4.6  23.7  295  21 11   7.7   4.2
 14000  -3.5  25.7  295  19 10   8.7   4.8 |  -3.4  25.9  295  23 12   8.1   4.5
 13500  -2.2  28.0  295  21 11   8.7   4.8 |  -2.2  28.0  300  26 13   8.2   4.5
 13000  -0.9  30.4  295  22 11   8.0   4.4 |  -1.1  30.0  300  28 15   7.1   3.9
 12500   0.3  32.5  295  25 13   8.1   4.4 |  -0.0  32.0  295  32 16   7.1   3.9
 12000   1.5  34.7  295  27 14   7.7   4.2 |   1.0  33.8  295  35 18   6.9   3.8
 11500   2.6  36.7  295  28 15   7.8   4.3 |   2.1  35.8  295  37 19   6.9   3.8
 11000   3.7  38.7  295  30 15   6.8   3.8 |   3.0  37.4  295  38 20   5.6   3.1
 10500   4.7  40.5  295  31 16   7.4   4.1 |   3.8  38.8  295  38 19   6.0   3.3
 10250   5.2  41.4  295  32 17   4.1   2.3 |   4.2  39.6  295  37 19   3.1   1.7
 10000   5.4  41.7  290  32 17   4.5   2.5 |   4.3  39.7  295  37 19   4.0   2.2
  9750   5.9  42.6  290  32 17   8.0   4.4 |   4.8  40.6  295  36 19   7.5   4.1
  9500   6.4  43.5  290  32 16   7.5   4.1 |   5.3  41.5  295  35 18   7.0   3.9
  9250   6.9  44.4  290  32 16   6.3   3.5 |   5.8  42.4  295  34 18   5.6   3.1
  9000   7.3  45.1  290  31 16   5.0   2.7 |   6.1  43.0  295  33 17   3.6   2.0
  8750   7.7  45.9  290  30 16   5.6   3.1 |   6.3  43.3  295  31 16   4.1   2.2
  8500   8.1  46.6  285  30 15   5.7   3.1 |   6.6  43.9  295  29 15   4.1   2.2
  8250   8.5  47.3  285  29 15   4.7   2.6 |   6.9  44.4  295  28 14   4.6   2.5
  8000   8.8  47.8  285  26 14   3.8   2.1 |   7.2  45.0  295  24 13   5.1   2.8
  7750   9.0  48.2  280  24 12   3.6   2.0 |   7.6  45.7  290  21 11   4.9   2.7
  7500   9.3  48.7  280  21 11   3.4   1.9 |   8.0  46.4  290  18  9   5.0   2.7
  7250   9.5  49.1  280  19 10   4.0   2.2 |   8.3  46.9  290  15  8   5.3   2.9
  7000   9.8  49.6  275  16  8   3.5   1.9 |   8.7  47.7  290  12  6   5.1   2.8
  6750  10.1  50.2  270  13  7   5.2   2.9 |   9.1  48.4  285   9  5   6.2   3.4
  6500  10.3  50.5  265  10  5  -4.9  -2.7 |   9.5  49.1  285   6  3   1.5   0.8
  6250   9.3  48.7  255   9  5 -14.6  -8.0 |   9.3  48.7  270   5  3  -3.3  -1.8
  6000   8.4  47.1  245   8  4 -10.4  -5.7 |   9.1  48.4  250   4  2  -1.1  -0.6
  5750   7.4  45.3  230   8  4 -17.4  -9.5 |   8.9  48.0  225   4  2  -4.0  -2.2
  5500   5.1  41.2  220   7  4 -46.2 -25.3 |   8.1  46.6  210   4  2 -15.9  -8.7

           02/13/2016 at 1400 MST          |       02/13/2016 at 1700 MST
                                           |
K index... -11.7  LI... +5.6               | K index... +5.6  LI... +5.1
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... -0.6
                                           |
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 -56.6 -69.9  280  64 33  -1.2  -0.6 | -56.7 -70.1  280  67 35  -2.7  -1.5
 45000 -58.5 -73.3  275  90 46  -2.2  -1.2 | -60.8 -77.4  275  85 44  -2.8  -1.5
 40000 -64.5 -84.1  275  81 42  -4.0  -2.2 | -64.3 -83.7  270  80 41  -2.2  -1.2
 38000 -63.3 -81.9  270  77 40   7.6   4.1 | -62.8 -81.0  270  78 40   7.0   3.8
 36000 -58.8 -73.8  270  74 38   7.6   4.2 | -58.6 -73.5  270  76 39   7.0   3.8
 34000 -54.2 -65.6  270  70 36   8.1   4.4 | -54.3 -65.7  270  74 38   8.4   4.6
 32000 -49.3 -56.7  265  61 32   8.1   4.4 | -49.2 -56.6  270  70 36   8.4   4.6
 30000 -43.8 -46.8  260  53 27   8.6   4.7 | -44.3 -47.7  270  66 34   7.8   4.3
 29000 -41.2 -42.2  255  49 25   8.6   4.7 | -41.9 -43.4  275  64 33   7.9   4.3
 28000 -38.6 -37.5  255  46 24   8.6   4.7 | -39.0 -38.2  275  61 31   7.9   4.3
 27000 -36.1 -33.0  250  43 22   8.6   4.7 | -36.6 -33.9  275  58 30   8.6   4.7
 26000 -33.5 -28.3  255  41 21   8.6   4.7 | -34.0 -29.2  270  55 28   8.7   4.8
 25000 -30.9 -23.6  260  38 20   8.6   4.7 | -31.4 -24.5  270  51 26   8.7   4.8
 24000 -28.4 -19.1  270  37 19   8.4   4.6 | -28.8 -19.8  265  48 25   8.5   4.7
 23000 -25.9 -14.6  270  35 18   8.3   4.6 | -26.3 -15.3  270  48 25   8.4   4.6
 22000 -23.4 -10.1  275  34 17   8.3   4.6 | -23.8 -10.8  270  48 25   8.4   4.6
 21000 -20.9  -5.6  280  33 17   7.9   4.3 | -21.4  -6.5  275  48 25   7.4   4.0
 20000 -18.5  -1.3  280  32 16   7.9   4.3 | -19.2  -2.6  280  49 25   7.4   4.0
 19500 -17.3   0.9  285  31 16   7.9   4.3 | -18.1  -0.6  280  49 25   7.4   4.0
 19000 -16.2   2.8  285  31 16   7.9   4.3 | -17.0   1.4  285  50 26   7.4   4.0
 18500 -15.0   5.0  285  31 16   7.5   4.1 | -15.9   3.4  285  50 26   7.0   3.8
 18000 -13.9   7.0  285  30 16   7.4   4.1 | -14.9   5.2  290  50 26   6.9   3.8
 17500 -12.8   9.0  290  30 16   7.4   4.1 | -13.9   7.0  290  50 26   6.8   3.7
 17000 -11.7  10.9  290  32 16   7.3   4.0 | -12.9   8.8  290  51 26   6.5   3.6
 16500 -10.6  12.9  290  34 17   7.4   4.1 | -11.9  10.6  295  51 26   6.5   3.6
 16000  -9.0  15.8  290  36 19   6.4   3.5 | -11.0  12.2  295  51 26   6.6   3.6
 15500  -8.1  17.4  295  37 19   6.4   3.5 | -10.0  14.0  295  51 26   6.6   3.6
 15000  -7.1  19.2  295  39 20   6.3   3.5 |  -8.5  16.7  295  51 26   6.6   3.6
 14500  -6.2  20.8  295  40 21   6.4   3.5 |  -7.5  18.5  295  50 26   6.6   3.6
 14000  -5.2  22.6  295  41 21   6.4   3.5 |  -6.6  20.1  295  49 25   6.4   3.5
 13500  -4.3  24.3  295  40 21   6.4   3.5 |  -5.6  21.9  295  48 25   6.4   3.5
 13000  -3.4  25.9  295  40 21   5.8   3.2 |  -4.7  23.5  295  47 24   6.3   3.5
 12500  -2.6  27.3  295  40 20   5.6   3.1 |  -3.7  25.3  300  45 23   6.3   3.4
 12000  -1.7  28.9  295  39 20   6.2   3.4 |  -2.8  27.0  300  44 22   6.6   3.6
 11500  -0.8  30.6  295  38 19   6.5   3.6 |  -1.8  28.8  295  42 21   6.9   3.8
 11000   0.2  32.4  295  36 19   6.3   3.5 |  -0.8  30.6  295  39 20   5.6   3.1
 10500   1.0  33.8  295  34 18   6.8   3.7 |  -0.1  31.8  295  38 19   4.4   2.4
 10250   1.5  34.7  295  33 17   3.8   2.1 |   0.3  32.5  295  37 19   7.4   4.1
 10000   1.7  35.1  295  32 17   4.7   2.6 |   0.9  33.6  295  35 18   8.6   4.7
  9750   2.2  36.0  295  31 16   8.2   4.5 |   1.4  34.5  295  33 17   6.2   3.4
  9500   2.8  37.0  295  29 15   7.6   4.2 |   1.9  35.4  290  31 16   7.1   3.9
  9250   3.3  37.9  295  27 14   6.7   3.7 |   2.4  36.3  290  30 15   6.0   3.3
  9000   3.7  38.7  295  25 13   6.4   3.5 |   2.8  37.0  290  28 14   6.2   3.4
  8750   4.3  39.7  295  23 12   8.0   4.4 |   3.3  37.9  285  26 13   7.8   4.3
  8500   4.9  40.8  290  21 11   8.0   4.4 |   3.9  39.0  285  24 12   7.8   4.3
  8250   5.5  41.9  290  19 10   8.3   4.5 |   4.5  40.1  280  22 11   8.0   4.4
  8000   6.1  43.0  290  17  9   8.5   4.7 |   5.1  41.2  280  20 10   8.2   4.5
  7750   6.7  44.1  285  15  8   8.2   4.5 |   5.7  42.3  275  18  9   8.3   4.5
  7500   7.3  45.1  285  13  7   8.0   4.4 |   6.3  43.3  270  16  8   8.4   4.6
  7250   7.9  46.2  280  11  6   8.0   4.4 |   6.9  44.4  265  15  8   9.4   5.1
  7000   8.5  47.3  275   9  5   7.9   4.3 |   7.7  45.9  265  14  7  10.1   5.5
  6750   9.1  48.4  265   7  4   8.3   4.6 |   8.4  47.1  260  13  7   8.9   4.9
  6500   9.7  49.5  255   5  3   7.5   4.1 |   9.0  48.2  255  12  6   8.7   4.8
  6250  10.1  50.2  240   5  2   6.1   3.4 |   9.7  49.5  250  11  6   9.2   5.0
  6000  10.6  51.1  220   4  2   6.6   3.6 |  10.3  50.5  250  11  5   9.9   5.4
  5750  11.0  51.8  205   4  2   6.1   3.3 |  11.0  51.8  245  10  5   7.5   4.1
  5500  11.1  52.0  195   4  2   2.1   1.1 |  11.2  52.2  240   8  4  -3.8  -2.1
________________________________________________________________________________

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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