Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 261320
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0620 MST Monday, January 26, 2015

This forecast is for Monday, January 26, 2015:

If the trigger temperature of 66.2 F/19.0 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 481 ft/min (2.4 m/s)
   Maximum height of thermals.................. 11497 ft MSL (6212 ft AGL)

Forecast maximum temperature................... 70.0 F/21.6 C
Time of trigger temperature.................... 1230 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8431 ft MSL (3145 ft AGL)
Thermal soaring outlook for Tuesday 01/27...... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 15104 ft MSL (9819 ft AGL)
Wave soaring outlook for Tuesday 01/27......... Poor

Remarks... Strong upper ridge will pass over colorado today and tonight.

Sunrise/Sunset.................... 07:12:27 / 17:10:37 MST
Total possible sunshine........... 9 hr 58 min 10 sec (598 min 10 sec)
Altitude of sun at 12:11:55 MST... 31.64 degrees

Upper air data from rawinsonde observation taken on 01/26/2015 at 0500 MST

Freezing level.................. 13194 ft MSL (7909 ft AGL)
Convective condensation level... 19930 ft MSL (14645 ft AGL)
Lifted condensation level....... 16712 ft MSL (11427 ft AGL)
Lifted index.................... +5.1
K index......................... +4.3

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  -61.1 -78.0   310   27   14  -4.9  -2.7   96.4 205.5    43.2      M    M
 45000  -59.7 -75.5   340   47   24  -1.2  -0.7   74.0 165.3    32.5      M    M
 40000  -65.8 -86.4   300   39   20   7.3   4.0   40.6 105.1    12.9      M    M
 38000  -60.5 -76.9   310   37   19   8.9   4.9   39.7 103.5    12.7      M    M
 36000  -55.1 -67.2   320   35   18   8.6   4.7   39.1 102.4    12.6      M    M
 34000  -50.6 -59.1   340   38   20   8.4   4.6   37.3  99.1    11.6      M    M
 32000  -45.2 -49.4   330   41   21   8.7   4.8   36.6  97.9    11.4      M    M
 30000  -39.9 -39.8   325   42   22   8.9   4.9   35.9  96.6    11.2      M    M
 29000  -37.3 -35.1   325   43   22   9.0   4.9   35.6  96.0    11.0      M    M
 28000  -34.5 -30.1   330   45   23   9.2   5.1   35.3  95.6    11.0      M    M
 27000  -31.3 -24.3   330   47   24   8.1   4.4   34.8  94.6    10.7      M    M
 26000  -28.8 -19.8   335   48   25   8.6   4.7   34.3  93.7    10.5      M    M
 25000  -26.2 -15.2   335   50   26   8.3   4.6   33.9  93.0    10.2      M    M
 24000  -24.1 -11.4   335   51   26   5.5   3.0   32.9  91.3     9.6      M    M
 23000  -21.7  -7.1   330   54   28   9.1   5.0   32.3  90.1     9.1      M    M
 22000  -19.1  -2.4   330   50   26   8.8   4.8   31.9  89.4     8.9      M    M
 21000  -16.5   2.3   325   46   24   7.9   4.3   31.6  88.9     8.8      M    M
 20000  -14.6   5.7   335   39   20   6.3   3.4   30.4  86.8     7.9      M    M
 19500  -13.6   7.5   340   37   19   6.3   3.4   29.8  85.6     7.3      M    M
 19000  -12.7   9.1   345   35   18   6.5   3.6   29.2  84.6     6.9      M    M
 18500  -11.7  10.9   345   34   17   6.7   3.7   28.6  83.6     6.4      M    M
 18000  -10.7  12.7   345   33   17   6.8   3.7   28.1  82.6     6.0      M    M
 17500   -9.7  14.5   350   31   16   6.8   3.7   27.6  81.7     5.6      M    M
 17000   -8.7  16.3   350   30   16   6.8   3.7   27.2  80.9     5.2      M    M
 16500   -7.7  18.1   360   34   18   6.8   3.7   26.6  80.0     4.7      M    M
 16000   -6.7  19.9   005   40   21   6.8   3.7   26.1  79.1     4.3      M    M
 15500   -5.7  21.7   005   42   22   7.1   3.9   25.6  78.1     3.8      M    M
 15000   -4.5  23.9   010   43   22   8.4   4.6   25.3  77.6     3.6      M    M
 14500   -3.3  26.1   010   43   22   8.3   4.6   25.1  77.2     3.4      M    M
 14000   -2.1  28.2   005   43   22   8.3   4.5   24.9  76.8     3.2      M    M
 13500   -0.4  31.3   005   44   23   6.3   3.4   24.4  75.9     2.7      M    M
 13000    0.6  33.1   360   45   23   6.3   3.4   23.8  74.8     2.1      M    M
 12500    1.5  34.7   360   46   24   6.4   3.5   23.2  73.8     1.6      M    M
 12000    2.3  36.1   360   46   24   3.3   1.8   22.6  72.6     1.0      M    M
 11500    2.6  36.7   360   41   21   2.0   1.1   21.3  70.4    -0.2    477  2.4
 11000    3.1  37.6   355   36   19   6.3   3.5   20.3  68.6    -1.1    447  2.3
 10500    4.1  39.4   355   31   16   7.4   4.1   19.9  67.9    -1.5    401  2.0
 10250    4.7  40.5   355   29   15   8.3   4.5   19.8  67.6    -1.7    376  1.9
 10000    5.4  41.7   355   27   14   8.5   4.7   19.7  67.4    -1.8    349  1.8
  9750    6.0  42.8   350   24   13   8.4   4.6   19.6  67.2    -1.9    323  1.6
  9500    6.6  43.9   350   22   11   8.5   4.7   19.5  67.1    -2.0    297  1.5
  9250    7.2  45.0   345   20   10   8.3   4.6   19.4  66.9    -2.1    271  1.4
  9000    7.9  46.2   345   17    9   9.0   4.9   19.3  66.8    -2.2    245  1.2
  8750    8.5  47.3   340   13    7   6.6   3.6   19.2  66.6    -2.3    218  1.1
  8500    8.7  47.7   335    9    5  -2.1  -1.1   18.7  65.6    -2.8    205  1.0
  8250    8.5  47.3   320    5    3   0.7   0.4   17.7  63.8    -3.8    205  1.0
  8000    8.9  48.0   275    3    2   9.1   5.0   17.4  63.3    -4.1    184  0.9
  7750    9.6  49.3   255    4    2   9.3   5.1   17.4  63.3    -4.1    156  0.8
  7500   10.3  50.5   245    4    2   9.2   5.1   17.3  63.2    -4.2    128  0.6
  7250   11.0  51.8   235    5    3   9.3   5.1   17.3  63.1    -4.2    100  0.5
  7000   11.7  53.1   230    6    3   9.0   5.0   17.3  63.1    -4.2     72  0.4
  6750   12.3  54.1   225    7    4  10.1   5.5   17.2  63.0    -4.3     44  0.2
  6500   13.0  55.4   225    9    5   6.2   3.4   17.2  63.0    -4.4     16  0.1
  6250   13.2  55.8   220   10    5   0.2   0.1   16.6  62.0    -4.9      4  0.0
  6000   13.2  55.8   220   12    6   0.6   0.3   15.9  60.7    -5.7      M    M
  5750   12.6  54.7   220    8    4 -24.0 -13.2   14.6  58.4    -7.0      6  0.0
  5500    8.9  48.0   220    4    2 -75.1 -41.2   10.2  50.4   -11.4    110  0.6

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

           01/26/2015 at 0800 MST          |       01/26/2015 at 1100 MST
                                           |
K index... +4.0  LI... +5.5                | K index... +3.9  LI... +5.1
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 -64.2 -83.6  320  40 21   2.7   1.5 | -65.4 -85.7  330  42 22   3.7   2.0
 45000 -60.7 -77.3  340  46 24  -1.6  -0.9 | -60.7 -77.3  335  40 21  -1.6  -0.9
 40000 -63.1 -81.6  300  31 16  -1.7  -0.9 | -63.4 -82.1  300  39 20  -2.0  -1.1
 38000 -60.2 -76.4  300  31 16   6.8   3.7 | -60.1 -76.2  295  39 20   7.2   3.9
 36000 -56.1 -69.0  310  34 17   6.8   3.7 | -55.8 -68.4  295  40 20   7.2   3.9
 34000 -50.6 -59.1  320  36 18   9.4   5.2 | -50.3 -58.5  295  39 20   9.1   5.0
 32000 -44.9 -48.8  325  37 19   9.4   5.2 | -44.8 -48.6  300  37 19   9.1   5.0
 30000 -39.3 -38.7  330  38 19   9.2   5.1 | -39.5 -39.1  310  33 17   8.5   4.7
 29000 -36.6 -33.9  335  38 20   9.2   5.1 | -37.0 -34.6  320  30 15   8.5   4.7
 28000 -33.8 -28.8  340  39 20   9.3   5.1 | -34.4 -29.9  330  28 15   8.4   4.6
 27000 -31.2 -24.2  340  39 20   8.3   4.5 | -31.8 -25.2  335  27 14   9.2   5.0
 26000 -28.7 -19.7  345  39 20   8.3   4.5 | -29.0 -20.2  335  26 13   9.2   5.0
 25000 -26.2 -15.2  345  39 20   8.2   4.5 | -26.2 -15.2  335  25 13   9.1   5.0
 24000 -24.1 -11.4  345  37 19   5.9   3.2 | -24.0 -11.2  335  25 13   5.8   3.2
 23000 -22.4  -8.3  340  34 18   5.9   3.2 | -22.3  -8.1  340  25 13   5.7   3.1
 22000 -20.6  -5.1  340  32 16   5.9   3.2 | -20.6  -5.1  345  25 13   5.6   3.1
 21000 -18.5  -1.3  340  30 15   8.0   4.4 | -18.5  -1.3  345  24 12   8.1   4.5
 20000 -16.1   3.0  335  28 14   8.0   4.4 | -16.0   3.2  340  22 11   8.2   4.5
 19500 -14.8   5.4  335  27 14   8.0   4.4 | -14.8   5.4  340  21 11   8.2   4.5
 19000 -13.6   7.5  335  26 13   8.0   4.4 | -13.6   7.5  340  20 10   8.0   4.4
 18500 -12.4   9.7  345  28 14   8.1   4.4 | -12.4   9.7  345  22 11   7.8   4.3
 18000 -11.2  11.8  350  31 16   8.3   4.5 | -11.2  11.8  345  23 12   7.9   4.3
 17500 -10.2  13.6  355  33 17   6.0   3.3 | -10.1  13.8  350  25 13   6.9   3.8
 17000  -9.3  15.3  360  34 18   6.1   3.4 |  -9.1  15.6  355  26 14   7.0   3.8
 16500  -7.9  17.8  005  35 18   6.6   3.6 |  -7.5  18.5  355  28 15   7.3   4.0
 16000  -6.9  19.6  005  36 18   6.5   3.6 |  -6.5  20.3  360  29 15   7.2   4.0
 15500  -5.9  21.4  010  36 19   7.2   4.0 |  -5.4  22.3  360  29 15   7.4   4.0
 15000  -4.8  23.4  010  36 18   7.4   4.1 |  -4.3  24.3  005  29 15   7.4   4.0
 14500  -3.7  25.3  010  35 18   7.3   4.0 |  -3.2  26.2  005  28 15   7.1   3.9
 14000  -2.7  27.1  010  33 17   7.2   3.9 |  -2.2  28.0  005  28 14   6.9   3.8
 13500  -1.6  29.1  010  32 16   7.0   3.9 |  -1.2  29.8  010  27 14   7.0   3.9
 13000  -0.6  30.9  010  30 15   6.6   3.6 |  -0.1  31.8  010  26 14   7.2   3.9
 12500   0.4  32.7  005  28 14   6.4   3.5 |   1.0  33.8  010  26 13   7.1   3.9
 12000   1.3  34.3  005  27 14   5.6   3.1 |   2.0  35.6  010  25 13   7.0   3.8
 11500   2.1  35.8  005  26 14   5.7   3.1 |   3.1  37.6  015  25 13   6.8   3.7
 11000   2.9  37.2  360  25 13   5.9   3.2 |   4.0  39.2  010  24 12   6.0   3.3
 10500   3.8  38.8  360  24 13   4.7   2.6 |   4.9  40.8  010  23 12   4.5   2.4
 10250   4.0  39.2  360  24 12   2.5   1.4 |   5.1  41.2  010  23 12   2.7   1.5
 10000   4.3  39.7  355  23 12   6.9   3.8 |   5.4  41.7  005  22 11   6.9   3.8
  9750   5.0  41.0  355  21 11  10.5   5.8 |   6.1  43.0  005  20 10   9.4   5.2
  9500   5.7  42.3  350  19 10   8.5   4.7 |   6.7  44.1  360  17  9   8.0   4.4
  9250   6.2  43.2  350  19 10   6.4   3.5 |   7.2  45.0  360  17  9   6.5   3.6
  9000   6.7  44.1  350  19 10   8.3   4.6 |   7.7  45.9  355  17  9   8.5   4.7
  8750   7.5  45.5  350  20 10  11.5   6.3 |   8.5  47.3  355  17  9  10.7   5.9
  8500   8.4  47.1  350  21 11   9.7   5.3 |   9.2  48.6  355  17  9   8.7   4.8
  8250   9.0  48.2  350  21 11   8.0   4.4 |   9.8  49.6  355  17  9   7.2   4.0
  8000   9.6  49.3  350  20 11   8.9   4.9 |  10.4  50.7  350  16  8   8.3   4.6
  7750  10.3  50.5  350  20 10   8.9   4.9 |  11.0  51.8  350  15  8   8.5   4.6
  7500  10.9  51.6  345  18 10   6.9   3.8 |  11.6  52.9  345  13  7   6.6   3.6
  7250  11.3  52.3  340  16  8   5.6   3.1 |  12.0  53.6  340  11  6   6.0   3.3
  7000  11.8  53.2  335  14  7   6.6   3.6 |  12.5  54.5  330  10  5   5.4   3.0
  6750  12.2  54.0  330  12  6   5.6   3.1 |  12.9  55.2  315   8  4   5.7   3.1
  6500  12.5  54.5  320  12  6   1.4   0.8 |  13.3  55.9  310   9  4   5.5   3.0
  6250  12.7  54.9  315  12  6   9.1   5.0 |  13.8  56.8  305   9  5   9.1   5.0
  6000  13.0  55.4  305  13  7 -18.6 -10.2 |  14.2  57.6  300  10  5  -5.2  -2.9
  5750   9.6  49.3  285  11  6 -61.2 -33.6 |  12.9  55.2  280   8  4 -18.5 -10.1
  5500   5.1  41.2  260   8  4 -49.0 -26.9 |  12.2  54.0  260   6  3   2.5   1.4

           01/26/2015 at 1400 MST          |       01/26/2015 at 1700 MST
                                           |
K index... +2.8  LI... +4.6                | K index... -0.7  LI... +4.7
CAPE... 0.0  CIN... -0.3                   | 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 -65.0 -85.0  325  40 21   4.7   2.6 | -65.1 -85.2  320  40 20   4.8   2.6
 45000 -59.1 -74.4  325  42 21  -2.5  -1.4 | -59.0 -74.2  320  39 20  -2.2  -1.2
 40000 -63.4 -82.1  300  47 24  -4.0  -2.2 | -62.9 -81.2  310  45 23  -3.3  -1.8
 38000 -59.8 -75.6  295  46 23   7.3   4.0 | -59.6 -75.3  300  44 23   7.0   3.8
 36000 -55.5 -67.9  295  44 23   7.3   4.0 | -55.4 -67.7  295  44 22   7.0   3.8
 34000 -50.7 -59.3  290  41 21   8.6   4.7 | -50.7 -59.3  295  41 21   8.5   4.6
 32000 -45.6 -50.1  290  38 19   8.6   4.7 | -45.7 -50.3  295  35 18   8.5   4.6
 30000 -40.3 -40.5  295  34 17   9.1   5.0 | -40.4 -40.7  300  32 16   9.0   4.9
 29000 -37.6 -35.7  295  31 16   9.1   5.0 | -37.1 -34.8  300  31 16   9.0   4.9
 28000 -34.2 -29.6  295  28 15   9.1   5.0 | -34.4 -29.9  300  30 16   9.1   5.0
 27000 -31.5 -24.7  300  26 13   9.0   4.9 | -31.8 -25.2  305  29 15   8.5   4.6
 26000 -28.8 -19.8  310  24 12   9.0   4.9 | -29.3 -20.7  305  27 14   8.5   4.6
 25000 -26.1 -15.0  320  23 12   9.0   4.9 | -26.7 -16.1  310  25 13   8.5   4.6
 24000 -23.8 -10.8  325  22 11   6.9   3.8 | -24.4 -11.9  315  23 12   7.6   4.2
 23000 -21.8  -7.2  335  21 11   6.8   3.7 | -22.1  -7.8  325  20 11   7.5   4.1
 22000 -19.7  -3.5  345  21 11   6.8   3.7 | -19.9  -3.8  335  19 10   7.5   4.1
 21000 -17.6   0.3  350  21 11   7.3   4.0 | -17.6   0.3  345  18  9   7.8   4.3
 20000 -15.4   4.3  350  22 11   7.3   4.0 | -15.2   4.6  350  18  9   7.8   4.3
 19500 -14.4   6.1  350  22 11   7.3   4.0 | -14.1   6.6  350  18  9   7.8   4.3
 19000 -13.3   8.1  350  22 11   7.6   4.2 | -12.9   8.8  350  17  9   7.7   4.2
 18500 -12.1  10.2  350  22 11   7.7   4.2 | -11.8  10.8  350  17  9   7.6   4.2
 18000 -11.0  12.2  350  22 11   7.7   4.2 | -10.6  12.9  350  16  8   7.6   4.2
 17500  -9.8  14.4  350  22 11   7.6   4.2 |  -9.5  14.9  350  15  8   7.7   4.2
 17000  -8.7  16.3  355  22 11   7.7   4.2 |  -8.3  17.1  350  15  8   7.7   4.2
 16500  -7.6  18.3  355  22 12   7.6   4.2 |  -7.2  19.0  355  14  7   7.3   4.0
 16000  -6.5  20.3  355  22 12   7.6   4.2 |  -6.1  21.0  355  14  7   7.2   4.0
 15500  -5.3  22.5  360  22 12   7.6   4.2 |  -5.1  22.8  355  14  7   7.2   4.0
 15000  -4.2  24.4  360  22 12   7.6   4.2 |  -4.0  24.8  360  14  7   7.4   4.0
 14500  -3.1  26.4  360  22 12   7.6   4.2 |  -2.4  27.7  360  14  7   7.4   4.0
 14000  -1.5  29.3  005  22 11   7.4   4.0 |  -1.3  29.7  360  13  7   7.4   4.1
 13500  -0.4  31.3  005  22 11   7.2   4.0 |  -0.2  31.6  360  13  7   7.5   4.1
 13000   0.7  33.3  005  21 11   7.0   3.9 |   0.9  33.6  360  12  6   7.6   4.2
 12500   1.7  35.1  005  20 10   6.8   3.7 |   2.0  35.6  355  11  6   7.3   4.0
 12000   2.7  36.9  005  19 10   6.4   3.5 |   3.0  37.4  350  10  5   6.4   3.5
 11500   3.6  38.5  005  18  9   6.4   3.5 |   3.9  39.0  345  10  5   6.3   3.5
 11000   4.6  40.3  005  17  9   6.1   3.4 |   4.8  40.6  340   9  4   6.1   3.3
 10500   5.5  41.9  005  16  8   4.1   2.3 |   5.8  42.4  330   8  4   4.3   2.4
 10250   5.7  42.3  005  15  8   3.2   1.8 |   6.0  42.8  325   7  4   3.3   1.8
 10000   6.1  43.0  005  14  7   7.8   4.3 |   6.4  43.5  325   7  4   7.4   4.1
  9750   6.8  44.2  360  13  7   9.6   5.3 |   7.0  44.6  320   7  3   9.1   5.0
  9500   7.4  45.3  360  12  6   7.8   4.3 |   7.7  45.9  315   6  3   7.8   4.3
  9250   7.9  46.2  360  11  6   5.6   3.1 |   8.2  46.8  315   6  3   6.0   3.3
  9000   8.4  47.1  360  11  6   8.0   4.4 |   8.6  47.5  320   5  3   7.6   4.2
  8750   9.1  48.4  360  10  5  10.2   5.6 |   9.3  48.7  335   4  2   9.4   5.1
  8500   9.8  49.6  005  10  5   8.7   4.8 |   9.9  49.8  350   4  2   8.2   4.5
  8250  10.4  50.7  005  10  5   8.0   4.4 |  10.5  50.9  355   3  2   7.7   4.2
  8000  11.0  51.8  005  10  5   8.4   4.6 |  11.1  52.0  005   3  1   7.8   4.3
  7750  11.6  52.9  005  10  5   8.2   4.5 |  11.7  53.1  005   1  1   7.8   4.3
  7500  12.2  54.0  360   8  4   7.2   3.9 |  12.3  54.1  250   1  0   8.1   4.5
  7250  12.7  54.9  345   6  3   7.0   3.8 |  12.9  55.2  225   3  2   8.2   4.5
  7000  13.2  55.8  315   4  2   6.3   3.5 |  13.5  56.3  220   5  3   8.5   4.6
  6750  13.7  56.7  270   4  2   6.7   3.7 |  14.2  57.6  215   8  4   8.6   4.7
  6500  14.2  57.6  260   5  2   8.0   4.4 |  14.7  58.5  220   9  4   7.3   4.0
  6250  14.7  58.5  255   5  3   7.6   4.2 |  15.3  59.5  220   9  5   9.5   5.2
  6000  15.2  59.4  250   6  3   8.4   4.6 |  15.9  60.6  225   9  5   1.2   0.7
  5750  15.9  60.6  245   6  3   8.9   4.9 |  15.0  59.0  220   9  5 -17.3  -9.5
  5500  16.4  61.5  235   5  3   7.6   4.1 |  13.2  55.8  210   8  4 -22.6 -12.4
________________________________________________________________________________

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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