Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 191306
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0606 MST Monday, January 19, 2015

This forecast is for Monday, January 19, 2015:

If the trigger temperature of 57.8 F/14.3 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 353 ft/min (1.8 m/s)
   Maximum height of thermals.................. 12012 ft MSL (6727 ft AGL)

Forecast maximum temperature................... 61.0 F/16.6 C
Time of trigger temperature.................... 1200 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6374 ft MSL (1088 ft AGL)
Thermal soaring outlook for Tuesday 01/20...... Poor

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Becoming fair
Height of stable layer (12-18K ft MSL)......... 12667 ft MSL (7382 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 13159 ft MSL (7874 ft AGL)
Wave soaring outlook for Tuesday 01/20......... Good

Remarks...

Sunrise/Sunset.................... 07:16:54 / 17:02:34 MST
Total possible sunshine........... 9 hr 45 min 40 sec (585 min 40 sec)
Altitude of sun at 12:10:08 MST... 30.01 degrees

Upper air data from rawinsonde observation taken on 01/19/2015 at 0500 MST

Freezing level.................. 10324 ft MSL (5039 ft AGL)
Convective condensation level... 17537 ft MSL (12252 ft AGL)
Lifted condensation level....... 15546 ft MSL (10261 ft AGL)
Lifted index.................... +2.2
K index......................... -16.6

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  -60.0 -76.0   250   31   16   8.9   4.9  101.9 215.5    48.8      M    M
 45000  -54.3 -65.7   300   58   30 -18.9 -10.3   85.6 186.0    42.4      M    M
 40000  -61.9 -79.4   290   79   41 -12.9  -7.1   50.1 122.2    22.2      M    M
 38000  -63.1 -81.6   290   75   39 -11.3  -6.2   39.4 103.0    15.7      M    M
 36000  -59.9 -75.8   280   65   33   4.6   2.5   35.5  95.9    13.4      M    M
 34000  -57.9 -72.2   275   56   29   1.2   0.7   30.2  86.3    10.0      M    M
 32000  -53.5 -64.3   265   48   25   9.6   5.3   28.0  82.4     8.7      M    M
 30000  -47.1 -52.8   275   48   25   9.4   5.2   27.7  81.9     8.7      M    M
 29000  -44.3 -47.7   275   48   25   9.4   5.2   27.5  81.5     8.7      M    M
 28000  -41.4 -42.5   270   47   24   9.4   5.2   27.4  81.4     8.7      M    M
 27000  -38.6 -37.5   270   47   24   9.4   5.2   27.4  81.4     8.8      M    M
 26000  -36.1 -33.0   280   45   23   6.0   3.3   26.9  80.4     8.5      M    M
 25000  -34.0 -29.2   290   44   23   7.5   4.1   25.8  78.5     7.8      M    M
 24000  -32.5 -26.5   285   43   22   6.7   3.7   24.1  75.3     6.4      M    M
 23000  -30.1 -22.2   285   44   23   8.1   4.5   23.4  74.2     6.0      M    M
 22000  -27.6 -17.7   285   45   23   8.5   4.7   22.9  73.3     5.6      M    M
 21000  -24.9 -12.8   285   46   24   9.0   5.0   22.6  72.7     5.4      M    M
 20000  -22.2  -8.0   285   47   24   9.0   5.0   22.4  72.4     5.4      M    M
 19500  -20.9  -5.6   285   47   24   9.1   5.0   22.3  72.1     5.3      M    M
 19000  -19.5  -3.1   285   46   24   8.5   4.7   22.1  71.9     5.2      M    M
 18500  -18.2  -0.8   295   44   23   9.0   4.9   21.9  71.5     5.0      M    M
 18000  -16.9   1.6   300   44   22   9.2   5.0   21.8  71.2     4.9      M    M
 17500  -15.5   4.1   300   43   22   9.2   5.0   21.7  71.0     4.8      M    M
 17000  -14.1   6.6   305   43   22   9.2   5.0   21.6  70.8     4.8      M    M
 16500  -12.7   9.1   305   43   22   9.2   5.0   21.5  70.7     4.8      M    M
 16000  -11.3  11.7   310   43   22   9.2   5.0   21.5  70.6     4.7      M    M
 15500  -10.0  14.0   305   42   22   8.9   4.9   21.4  70.5     4.7      M    M
 15000   -8.6  16.5   300   42   22   5.2   2.8   20.4  68.7     3.8      M    M
 14500   -8.1  17.4   295   42   22   2.9   1.6   19.4  66.9     3.0      M    M
 14000   -7.1  19.2   290   42   22   9.4   5.2   18.9  66.0     2.5      M    M
 13500   -5.8  21.6   290   43   22   9.5   5.2   18.7  65.7     2.3      M    M
 13000   -4.9  23.2   290   44   23   1.1   0.6   18.2  64.7     1.8      M    M
 12500   -4.7  23.5   290   45   23   4.9   2.7   16.9  62.3     0.5      M    M
 12000   -3.8  25.2   290   46   24   5.9   3.2   16.2  61.2    -0.1    546  2.8
 11500   -3.0  26.6   290   46   24   5.6   3.1   15.6  60.1    -0.7    506  2.6
 11000   -1.9  28.6   285   46   24  10.0   5.5   15.3  59.5    -1.1    457  2.3
 10500   -0.4  31.3   285   46   24   9.6   5.3   15.3  59.6    -1.1    398  2.0
 10250    0.4  32.7   285   46   24  10.9   6.0   15.3  59.6    -1.0    368  1.9
 10000    1.2  34.2   285   47   24   8.7   4.8   15.4  59.7    -1.0    337  1.7
  9750    1.6  34.9   285   44   23   5.8   3.2   15.1  59.2    -1.2    315  1.6
  9500    2.1  35.8   285   41   21   6.7   3.7   14.9  58.8    -1.5    294  1.5
  9250    2.5  36.5   280   38   20   6.1   3.3   14.6  58.3    -1.8    273  1.4
  9000    3.0  37.4   280   36   18   7.7   4.2   14.4  57.9    -2.1    252  1.3
  8750    3.7  38.7   280   34   18   9.3   5.1   14.3  57.8    -2.1    224  1.1
  8500    4.3  39.7   280   33   17   8.9   4.9   14.3  57.7    -2.2    197  1.0
  8250    5.0  41.0   285   31   16   9.0   4.9   14.2  57.6    -2.2    169  0.9
  8000    5.7  42.3   285   30   15   9.0   4.9   14.2  57.5    -2.3    142  0.7
  7750    6.4  43.5   285   28   14   9.0   4.9   14.1  57.4    -2.4    114  0.6
  7500    7.0  44.6   285   26   13   9.0   4.9   14.0  57.2    -2.4     87  0.4
  7250    7.7  45.9   285   24   12   9.0   5.0   14.0  57.1    -2.5     59  0.3
  7000    8.4  47.1   285   22   11   8.8   4.8   13.9  57.1    -2.6     32  0.2
  6750    9.0  48.2   285   20   10   9.8   5.4   13.9  56.9    -2.6      4  0.0
  6500    9.7  49.5   285   19   10   6.1   3.3   13.8  56.8    -2.7      M    M
  6250    9.9  49.8   280   17    9   2.1   1.2   13.3  55.9    -3.2      M    M
  6000   10.1  50.2   280   15    8   1.2   0.6   12.7  54.9    -3.8      M    M
  5750   10.2  50.4   275   11    5   6.2   3.4   12.1  53.8    -4.4      M    M
  5500   10.4  50.7   260    6    3 -12.8  -7.0   11.6  52.8    -5.0      M    M

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

           01/19/2015 at 0800 MST          |       01/19/2015 at 1100 MST
                                           |
K index... -2.8  LI... +3.9                | K index... +5.7  LI... +3.5
CAPE... 0.0  CIN... -0.4                   | CAPE... 0.0  CIN... -0.2
                                           |
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 -59.8 -75.6  290  40 20   2.5   1.4 | -60.3 -76.5  275  40 21   2.1   1.1
 45000 -55.9 -68.6  285  75 38   3.2   1.8 | -57.2 -71.0  290  73 38   1.9   1.1
 40000 -62.9 -81.2  290  82 42  -5.1  -2.8 | -61.7 -79.1  285  78 40  -3.5  -1.9
 38000 -63.7 -82.7  290  81 42   5.1   2.8 | -62.3 -80.1  285  79 40   3.5   1.9
 36000 -60.7 -77.3  285  76 39   5.0   2.8 | -60.2 -76.4  285  78 40   3.5   1.9
 34000 -57.6 -71.7  285  71 37   7.1   3.9 | -57.9 -72.2  285  78 40   7.4   4.0
 32000 -53.1 -63.6  285  62 32   7.5   4.1 | -53.0 -63.4  285  72 37   8.3   4.5
 30000 -47.9 -54.2  285  53 27   8.3   4.6 | -48.1 -54.6  290  66 34   7.8   4.3
 29000 -45.4 -49.7  285  50 26   8.4   4.6 | -45.2 -49.4  290  59 31   7.7   4.3
 28000 -42.9 -45.2  280  48 25   8.4   4.6 | -42.8 -45.0  290  54 28   7.7   4.3
 27000 -40.4 -40.7  280  46 24   8.0   4.4 | -40.5 -40.9  290  49 25   7.8   4.3
 26000 -38.1 -36.6  280  44 23   7.7   4.2 | -38.2 -36.8  290  45 23   7.8   4.3
 25000 -35.8 -32.4  280  42 22   7.7   4.2 | -35.9 -32.6  290  42 22   7.8   4.3
 24000 -33.5 -28.3  280  40 21   8.0   4.4 | -33.5 -28.3  285  39 20   8.1   4.4
 23000 -30.9 -23.6  280  39 20   8.5   4.7 | -31.0 -23.8  290  38 20   8.5   4.7
 22000 -28.4 -19.1  280  39 20   8.5   4.7 | -28.4 -19.1  290  38 19   8.5   4.7
 21000 -25.8 -14.4  280  38 20   9.0   4.9 | -25.9 -14.6  290  37 19   8.5   4.7
 20000 -23.1  -9.6  280  38 19   9.0   4.9 | -23.4 -10.1  290  36 19   8.5   4.7
 19500 -21.8  -7.2  285  37 19   9.0   4.9 | -22.1  -7.8  290  36 18   8.5   4.7
 19000 -20.4  -4.7  285  37 19   9.0   4.9 | -20.8  -5.4  285  35 18   8.5   4.7
 18500 -19.1  -2.4  285  37 19   9.0   5.0 | -19.5  -3.1  285  35 18   8.6   4.7
 18000 -17.7   0.1  285  37 19   9.0   4.9 | -18.2  -0.8  285  34 17   8.6   4.7
 17500 -16.4   2.5  285  36 19   8.9   4.9 | -17.0   1.4  285  32 17   8.5   4.7
 17000 -15.1   4.8  285  36 18   8.4   4.6 | -15.8   3.6  285  31 16   7.4   4.1
 16500 -13.8   7.2  285  36 18   8.4   4.6 | -14.7   5.5  285  31 16   7.4   4.1
 16000 -12.5   9.5  285  35 18   8.9   4.9 | -13.6   7.5  285  29 15   7.8   4.3
 15500 -11.2  11.8  285  34 18   8.9   4.9 | -12.4   9.7  285  28 14   7.8   4.3
 15000  -9.3  15.3  290  33 17   7.4   4.1 | -11.3  11.7  280  26 13   7.2   4.0
 14500  -8.2  17.2  290  32 17   7.6   4.2 |  -9.7  14.5  290  24 13   6.9   3.8
 14000  -7.1  19.2  295  32 16   7.0   3.8 |  -8.7  16.3  290  24 12   6.9   3.8
 13500  -6.0  21.2  295  32 16   7.0   3.9 |  -7.7  18.1  295  23 12   6.9   3.8
 13000  -5.0  23.0  300  32 17   6.6   3.6 |  -6.7  19.9  300  23 12   6.5   3.5
 12500  -4.1  24.6  300  35 18   6.7   3.7 |  -5.8  21.6  305  24 13   6.5   3.5
 12000  -3.2  26.2  305  36 18   5.2   2.8 |  -4.9  23.2  305  25 13   5.9   3.2
 11500  -2.5  27.5  305  33 17   4.9   2.7 |  -4.0  24.8  310  24 13   5.8   3.2
 11000  -1.8  28.8  310  32 17   5.7   3.2 |  -3.2  26.2  310  24 12   6.3   3.5
 10500  -0.9  30.4  310  35 18   6.5   3.6 |  -2.3  27.9  310  23 12   7.1   3.9
 10250  -0.5  31.1  305  36 18   3.6   2.0 |  -1.8  28.8  310  22 11   3.6   2.0
 10000  -0.3  31.5  305  36 19   4.4   2.4 |  -1.6  29.1  310  22 11   4.3   2.3
  9750   0.2  32.4  305  36 18   7.8   4.3 |  -1.1  30.0  310  21 11   8.1   4.4
  9500   0.7  33.3  305  35 18   7.4   4.1 |  -0.6  30.9  310  20 10   7.6   4.2
  9250   1.2  34.2  305  34 18   5.7   3.1 |  -0.0  32.0  315  19 10   5.7   3.1
  9000   1.5  34.7  305  33 17   4.3   2.4 |   0.3  32.5  310  18  9   4.3   2.4
  8750   1.9  35.4  305  31 16   5.8   3.2 |   0.7  33.3  315  17  9   6.5   3.6
  8500   2.3  36.1  305  29 15   6.0   3.3 |   1.2  34.2  315  16  8   6.7   3.7
  8250   2.7  36.9  305  27 14   6.0   3.3 |   1.6  34.9  315  15  7   6.5   3.6
  8000   3.2  37.8  305  25 13   6.1   3.3 |   2.1  35.8  315  13  7   6.5   3.6
  7750   3.7  38.7  300  23 12   6.7   3.7 |   2.6  36.7  315  12  6   7.4   4.1
  7500   4.2  39.6  300  20 10   6.8   3.7 |   3.2  37.8  315  10  5   7.7   4.2
  7250   4.6  40.3  300  18  9   6.3   3.4 |   3.8  38.8  315   8  4   7.3   4.0
  7000   5.1  41.2  295  15  8   6.4   3.5 |   4.3  39.7  310   7  3   7.3   4.0
  6750   5.6  42.1  290  13  6   5.8   3.2 |   4.9  40.8  300   5  3   7.8   4.3
  6500   5.9  42.6  285  10  5   2.4   1.3 |   5.5  41.9  285   4  2   8.4   4.6
  6250   5.9  42.6  270   9  4  -3.5  -1.9 |   6.1  43.0  265   4  2   8.2   4.5
  6000   5.8  42.4  250   8  4   9.0   4.9 |   6.7  44.1  245   4  2   9.2   5.1
  5750   6.5  43.7  235   8  4  -8.5  -4.7 |   7.5  45.5  230   5  3   9.0   5.0
  5500   3.2  37.8  210   7  3 -77.4 -42.5 |   8.0  46.4  220   4  2   5.8   3.2

           01/19/2015 at 1400 MST          |       01/19/2015 at 1700 MST
                                           |
K index... +10.1  LI... +2.9               | K index... +16.7  LI... +1.8
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -59.1 -74.4  285  40 21   2.1   1.1 | -58.9 -74.0  285  47 24   1.5   0.8
 45000 -55.9 -68.6  290  71 36   2.6   1.4 | -56.6 -69.9  290  63 33   1.4   0.8
 40000 -60.2 -76.4  290  78 40  -3.2  -1.8 | -59.1 -74.4  290  77 39  -1.9  -1.1
 38000 -61.1 -78.0  290  79 41   2.3   1.2 | -59.7 -75.5  290  79 41   1.0   0.5
 36000 -59.7 -75.5  285  78 40   2.3   1.3 | -59.0 -74.2  285  78 40   1.0   0.6
 34000 -58.3 -72.9  285  77 40   5.8   3.2 | -58.4 -73.1  285  77 40   4.4   2.4
 32000 -53.5 -64.3  285  70 36   7.9   4.3 | -54.0 -65.2  285  73 38   7.4   4.1
 30000 -48.2 -54.8  285  63 32   7.8   4.3 | -49.5 -57.1  285  69 35   8.4   4.6
 29000 -45.8 -50.4  285  59 30   7.9   4.3 | -46.9 -52.4  280  64 33   8.6   4.7
 28000 -43.5 -46.3  285  54 28   7.9   4.3 | -43.7 -46.7  280  59 30   8.6   4.7
 27000 -41.1 -42.0  285  50 26   7.9   4.3 | -41.2 -42.2  280  54 28   8.5   4.7
 26000 -38.8 -37.8  285  47 24   7.9   4.3 | -38.6 -37.5  280  51 26   8.5   4.6
 25000 -36.4 -33.5  285  44 22   7.9   4.3 | -36.1 -33.0  280  49 25   8.5   4.6
 24000 -34.0 -29.2  280  40 21   8.1   4.4 | -33.6 -28.5  280  46 24   8.4   4.6
 23000 -31.4 -24.5  285  39 20   8.8   4.8 | -31.2 -24.2  280  44 23   8.1   4.5
 22000 -28.8 -19.8  285  38 19   8.8   4.8 | -28.7 -19.7  280  43 22   8.2   4.5
 21000 -26.1 -15.0  285  37 19   8.7   4.8 | -26.3 -15.3  285  41 21   7.9   4.3
 20000 -23.6 -10.5  285  35 18   8.6   4.7 | -24.0 -11.2  285  38 20   7.7   4.2
 19500 -22.3  -8.1  285  34 18   8.6   4.7 | -22.8  -9.0  285  36 19   7.7   4.2
 19000 -21.0  -5.8  285  34 17   8.6   4.7 | -21.7  -7.1  285  35 18   7.7   4.2
 18500 -19.7  -3.5  285  33 17   8.2   4.5 | -20.5  -4.9  285  33 17   7.4   4.1
 18000 -18.5  -1.3  285  32 16   7.8   4.3 | -19.5  -3.1  285  32 16   7.0   3.8
 17500 -17.4   0.7  285  31 16   7.8   4.3 | -18.4  -1.1  285  30 15   7.0   3.8
 17000 -16.3   2.7  285  30 15   7.4   4.0 | -17.4   0.7  285  28 15   7.3   4.0
 16500 -15.2   4.6  285  29 15   7.4   4.1 | -16.3   2.7  285  27 14   7.3   4.0
 16000 -14.1   6.6  285  27 14   7.6   4.1 | -15.3   4.5  285  26 13   6.9   3.8
 15500 -12.9   8.8  285  26 14   7.6   4.2 | -14.3   6.3  285  25 13   6.8   3.7
 15000 -11.3  11.7  290  25 13   7.5   4.1 | -13.3   8.1  285  23 12   6.9   3.8
 14500 -10.2  13.6  290  25 13   7.6   4.1 | -11.7  10.9  290  23 12   7.1   3.9
 14000  -9.1  15.6  295  25 13   6.9   3.8 | -10.7  12.7  290  23 12   7.1   3.9
 13500  -8.1  17.4  295  25 13   6.9   3.8 |  -9.7  14.5  285  22 11   7.1   3.9
 13000  -7.1  19.2  295  25 13   6.7   3.7 |  -8.6  16.5  285  21 11   7.8   4.3
 12500  -6.1  21.0  295  25 13   6.8   3.7 |  -7.4  18.7  285  22 11   8.0   4.4
 12000  -5.2  22.6  295  25 13   5.8   3.2 |  -6.3  20.7  285  21 11   7.2   4.0
 11500  -4.4  24.1  290  23 12   5.5   3.0 |  -5.3  22.5  280  18  9   6.9   3.8
 11000  -3.6  25.5  285  22 11   6.1   3.3 |  -4.2  24.4  275  15  8   8.2   4.5
 10500  -2.7  27.1  285  21 11   6.9   3.8 |  -3.0  26.6  270  14  7   9.6   5.3
 10250  -2.2  28.0  280  20 10   4.0   2.2 |  -2.3  27.9  270  14  7   5.0   2.8
 10000  -2.0  28.4  280  20 11   4.8   2.7 |  -2.1  28.2  275  14  7   5.8   3.2
  9750  -1.5  29.3  280  19 10   8.3   4.5 |  -1.4  29.5  270  13  7  10.9   6.0
  9500  -0.9  30.4  280  18  9   7.7   4.2 |  -0.6  30.9  265  12  6   9.9   5.4
  9250  -0.4  31.3  275  16  8   6.4   3.5 |   0.1  32.2  260  11  5   8.8   4.8
  9000   0.0  32.0  270  15  8   5.7   3.1 |   0.7  33.3  255  10  5   8.1   4.4
  8750   0.5  32.9  265  13  7   7.6   4.2 |   1.4  34.5  255   9  5   9.6   5.3
  8500   1.1  34.0  255  12  6   7.9   4.3 |   2.1  35.8  250   9  5   9.9   5.4
  8250   1.7  35.1  245  11  6   7.8   4.3 |   2.8  37.0  250   9  4   9.2   5.0
  8000   2.3  36.1  240  10  5   8.0   4.4 |   3.5  38.3  245   8  4   8.5   4.7
  7750   2.9  37.2  230   9  5   9.0   5.0 |   4.1  39.4  240   8  4   8.7   4.8
  7500   3.6  38.5  225   8  4   9.7   5.3 |   4.8  40.6  240   8  4   8.2   4.5
  7250   4.3  39.7  220   7  4   9.6   5.3 |   5.3  41.5  235   7  4   7.3   4.0
  7000   5.1  41.2  215   7  4   9.7   5.3 |   5.9  42.6  230   6  3   7.0   3.9
  6750   5.8  42.4  215   6  3   9.2   5.0 |   6.4  43.5  220   4  2   6.8   3.7
  6500   6.5  43.7  210   6  3   9.8   5.4 |   6.8  44.2  205   3  1   5.9   3.2
  6250   7.2  45.0  210   5  3  10.7   5.9 |   7.2  45.0  160   2  1   5.2   2.8
  6000   8.0  46.4  210   5  2  10.0   5.5 |   7.6  45.7  125   3  2   6.3   3.5
  5750   8.8  47.8  210   4  2  10.5   5.8 |   8.0  46.4  110   5  3   2.7   1.5
  5500   9.6  49.3  205   3  2  13.2   7.3 |   7.7  45.9  110   5  3  -7.2  -4.0
________________________________________________________________________________

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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