Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 240205
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1904 MST Friday, January 23, 2015

This forecast is for Saturday, January 24, 2015:

If the trigger temperature of 53.7 F/12.0 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 326 ft/min (1.7 m/s)
   Maximum height of thermals.................. 9858 ft MSL (4571 ft AGL)

Forecast maximum temperature................... 55.0 F/13.2 C
Time of trigger temperature.................... 1315 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................. 8002 ft MSL (2715 ft AGL)
Thermal soaring outlook for Sunday 01/25....... Fair

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....................... 25947 ft MSL (20660 ft AGL)
Wave soaring outlook for Sunday 01/25.......... Fair

Remarks...

Sunrise/Sunset.................... 07:13:53 / 17:08:17 MST
Total possible sunshine........... 9 hr 54 min 25 sec (594 min 25 sec)
Altitude of sun at 12:11:28 MST... 31.15 degrees

Upper air data from numerical model forecast valid on 01/24/2015 at 0500 MST

Freezing level.................. 5668 ft MSL (381 ft AGL)
Additional freezing level....... 9330 ft MSL (4043 ft AGL)
Convective condensation level... 18069 ft MSL (12782 ft AGL)
Lifted condensation level....... 14927 ft MSL (9640 ft AGL)
Lifted index.................... +5.6
K index......................... -24.9

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  -59.0 -74.2   340   27   14   2.3   1.2      M     M       M      M    M
 45000  -55.5 -67.9   345   26   14   0.4   0.2      M     M       M      M    M
 40000  -57.0 -70.6   010   43   22  -1.0  -0.6      M     M       M      M    M
 38000  -57.2 -71.0   015   47   24   0.5   0.3      M     M       M      M    M
 36000  -56.9 -70.4   020   46   24   0.5   0.3      M     M       M      M    M
 34000  -56.1 -69.0   030   46   23   8.0   4.4      M     M       M      M    M
 32000  -51.6 -60.9   035   45   23   7.5   4.1      M     M       M      M    M
 30000  -46.3 -51.3   040   45   23   8.8   4.8   29.0  84.3    12.2      M    M
 29000  -43.6 -46.5   040   43   22   8.9   4.9   28.6  83.5    12.0      M    M
 28000  -41.0 -41.8   040   42   22   8.9   4.9   28.3  82.9    11.9      M    M
 27000  -38.4 -37.1   035   40   21   7.2   4.0   28.0  82.4    11.9      M    M
 26000  -36.4 -33.5   030   34   18   6.6   3.6   26.7  80.0    11.0      M    M
 25000  -34.4 -29.9   020   29   15   6.6   3.6   25.5  77.9    10.1      M    M
 24000  -32.4 -26.3   005   26   13   7.5   4.1   24.4  76.0     9.4      M    M
 23000  -29.9 -21.8   360   25   13   8.6   4.7   23.9  75.0     9.1      M    M
 22000  -27.3 -17.1   355   25   13   8.6   4.7   23.5  74.3     8.8      M    M
 21000  -24.7 -12.5   350   25   13   8.3   4.5   23.1  73.6     8.6      M    M
 20000  -22.3  -8.1   355   25   13   8.2   4.5   22.5  72.5     8.2      M    M
 19500  -21.0  -5.8   355   24   12   8.2   4.5   22.2  72.0     8.1      M    M
 19000  -19.8  -3.6   355   24   12   8.3   4.5   22.0  71.6     7.9      M    M
 18500  -18.6  -1.5   360   23   12   8.1   4.4   21.8  71.2     7.8      M    M
 18000  -17.4   0.7   360   22   11   8.0   4.4   21.5  70.6     7.5      M    M
 17500  -16.2   2.8   360   21   11   8.0   4.4   21.2  70.1     7.3      M    M
 17000  -15.0   5.0   360   20   10   7.8   4.3   20.8  69.5     7.1      M    M
 16500  -13.8   7.2   360   20   10   7.8   4.3   20.5  68.9     6.8      M    M
 16000  -12.6   9.3   360   19   10   8.0   4.4   20.2  68.4     6.6      M    M
 15500  -11.4  11.5   360   17    9   8.0   4.4   19.9  67.8     6.3      M    M
 15000   -9.7  14.5   360   15    8   7.3   4.0   19.4  66.9     5.9      M    M
 14500   -8.6  16.5   360   14    7   7.5   4.1   19.0  66.2     5.6      M    M
 14000   -7.6  18.3   360   13    7   5.9   3.2   18.5  65.3     5.2      M    M
 13500   -6.7  19.9   355   12    6   6.0   3.3   17.9  64.2     4.6      M    M
 13000   -5.8  21.6   350   11    6   5.8   3.2   17.2  63.0     4.1      M    M
 12500   -5.0  23.0   345   11    5   5.8   3.2   16.6  61.9     3.5      M    M
 12000   -4.1  24.6   340   10    5   6.4   3.5   16.0  60.8     2.9      M    M
 11500   -3.1  26.4   330   11    6   6.5   3.6   15.5  59.8     2.5      M    M
 11000   -2.2  28.0   325   11    6   5.1   2.8   14.9  58.8     1.9      M    M
 10500   -1.5  29.3   325   11    6   5.6   3.0   14.1  57.4     1.1      M    M
 10250   -1.2  29.8   320   11    6   2.5   1.4   13.7  56.7     0.8      M    M
 10000   -1.1  30.0   320   11    6   2.9   1.6   13.0  55.5     0.1      M    M
  9750   -0.7  30.7   320   11    6   6.5   3.6   12.7  54.9    -0.2    314  1.6
  9500   -0.2  31.6   320   12    6   6.7   3.7   12.4  54.4    -0.5    294  1.5
  9250    0.2  32.4   315   12    6   4.3   2.3   12.2  53.9    -0.8    273  1.4
  9000    0.3  32.5   310   11    6   2.4   1.3   11.6  52.9    -1.4    261  1.3
  8750    0.6  33.1   305   11    6   4.9   2.7   11.1  52.0    -1.9    247  1.3
  8500    0.9  33.6   300   10    5   5.4   3.0   10.8  51.4    -2.2    229  1.2
  8250    1.3  34.3   290   10    5   5.0   2.7   10.4  50.8    -2.6    211  1.1
  8000    1.6  34.9   285    9    5   4.9   2.7   10.1  50.1    -3.0    193  1.0
  7750    2.0  35.6   275    9    5   4.4   2.4    9.7  49.4    -3.4    175  0.9
  7500    2.3  36.1   265    9    5   5.7   3.1    9.3  48.7    -3.8    157  0.8
  7250    2.9  37.2   265    9    5   7.3   4.0    9.1  48.3    -4.0    134  0.7
  7000    3.4  38.1   265    9    5   7.4   4.1    8.9  48.0    -4.2    110  0.6
  6750    4.0  39.2   265    9    5   6.9   3.8    8.7  47.6    -4.4     86  0.4
  6500    4.3  39.7   270   10    5  -0.8  -0.5    8.3  46.9    -4.8     70  0.4
  6250    4.0  39.2   270   12    6  -0.8  -0.4    7.3  45.1    -5.8     69  0.4
  6000    3.8  38.8   270   14    7 -14.8  -8.1    6.3  43.3    -6.8     69  0.4
  5750    1.5  34.7   265   13    7 -41.8 -23.0    3.3  37.9    -9.8    131  0.7
  5500   -1.8  28.8   245    9    5 -40.1 -22.0   -0.7  30.7   -13.8    222  1.1

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

           01/24/2015 at 0800 MST          |       01/24/2015 at 1100 MST
                                           |
K index... -22.9  LI... +5.6               | K index... -23.4  LI... +7.0
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.8
                                           |
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  345  30 15   2.5   1.3 | -59.3 -74.7  345  28 14   2.5   1.4
 45000 -55.7 -68.3  350  33 17   0.4   0.2 | -55.5 -67.9  340  31 16   1.5   0.8
 40000 -56.9 -70.4  355  38 20  -0.8  -0.5 | -54.1 -65.4  355  35 18   1.0   0.5
 38000 -57.0 -70.6  360  39 20   0.8   0.4 | -54.5 -66.1  355  36 18  -2.4  -1.3
 36000 -56.5 -69.7  360  37 19   0.8   0.4 | -55.9 -68.6  360  35 18  -2.4  -1.3
 34000 -55.6 -68.1  360  35 18   7.9   4.3 | -56.6 -69.9  360  34 17   9.2   5.0
 32000 -51.4 -60.5  010  32 17   7.1   3.9 | -51.3 -60.3  350  31 16   7.8   4.3
 30000 -46.3 -51.3  015  31 16   8.8   4.8 | -46.3 -51.3  345  28 14   9.3   5.1
 29000 -43.6 -46.5  015  32 16   8.8   4.8 | -43.5 -46.3  345  25 13   9.3   5.1
 28000 -41.0 -41.8  015  32 17   8.8   4.8 | -40.7 -41.3  345  22 11   9.3   5.1
 27000 -38.4 -37.1  015  33 17   8.7   4.8 | -38.0 -36.4  340  20 10   8.8   4.8
 26000 -35.8 -32.4  015  30 16   8.6   4.7 | -35.4 -31.7  340  22 11   8.8   4.8
 25000 -33.2 -27.8  010  28 14   8.6   4.7 | -32.7 -26.9  340  24 12   8.8   4.8
 24000 -30.6 -23.1  005  26 13   8.1   4.4 | -30.1 -22.2  340  25 13   8.7   4.8
 23000 -28.3 -18.9  360  25 13   7.6   4.2 | -27.5 -17.5  340  26 13   8.7   4.8
 22000 -26.0 -14.8  360  24 12   7.6   4.2 | -24.8 -12.6  340  26 13   8.8   4.8
 21000 -23.8 -10.8  355  23 12   7.5   4.1 | -22.3  -8.1  335  26 14   6.9   3.8
 20000 -21.5  -6.7  355  23 12   7.5   4.1 | -20.3  -4.5  335  25 13   6.9   3.8
 19500 -20.4  -4.7  355  23 12   7.5   4.1 | -19.2  -2.6  330  25 13   6.9   3.8
 19000 -19.3  -2.7  355  23 12   7.5   4.1 | -18.2  -0.8  330  24 12   7.0   3.8
 18500 -18.2  -0.8  355  23 12   7.1   3.9 | -17.2   1.0  325  23 12   6.6   3.6
 18000 -17.1   1.2  355  22 11   7.0   3.8 | -16.2   2.8  325  21 11   6.5   3.6
 17500 -16.1   3.0  350  22 11   7.1   3.9 | -15.2   4.6  320  19 10   6.4   3.5
 17000 -14.9   5.2  350  21 11   7.7   4.2 | -14.3   6.3  320  18  9   6.0   3.3
 16500 -13.8   7.2  345  21 11   7.7   4.2 | -13.4   7.9  320  17  9   5.9   3.2
 16000 -12.7   9.1  345  21 11   7.5   4.1 | -11.9  10.6  315  17  9   6.8   3.7
 15500 -11.0  12.2  340  21 11   7.5   4.1 | -10.9  12.4  315  17  9   6.8   3.8
 15000  -9.8  14.4  340  20 10   7.7   4.2 |  -9.8  14.4  315  17  9   6.9   3.8
 14500  -8.6  16.5  335  20 10   7.8   4.3 |  -8.8  16.2  315  17  9   7.0   3.8
 14000  -7.6  18.3  335  19 10   6.8   3.7 |  -7.8  18.0  315  17  9   6.3   3.4
 13500  -6.5  20.3  330  19 10   6.9   3.8 |  -6.8  19.8  320  17  9   6.3   3.5
 13000  -5.5  22.1  330  18  9   6.8   3.7 |  -5.9  21.4  320  16  8   6.9   3.8
 12500  -4.5  23.9  330  17  9   6.8   3.7 |  -4.8  23.4  320  15  8   7.0   3.8
 12000  -3.5  25.7  330  16  8   6.6   3.6 |  -3.8  25.2  325  15  7   6.9   3.8
 11500  -2.5  27.5  325  15  8   6.6   3.6 |  -2.8  27.0  325  14  7   6.9   3.8
 11000  -1.6  29.1  325  14  7   5.2   2.8 |  -1.8  28.8  330  13  6   6.3   3.4
 10500  -0.9  30.4  320  14  7   5.7   3.1 |  -0.9  30.4  330  11  6   6.9   3.8
 10250  -0.5  31.1  320  13  7   2.4   1.3 |  -0.4  31.3  330  11  6   3.5   1.9
 10000  -0.5  31.1  320  13  7   2.6   1.4 |  -0.3  31.5  330  11  6   3.9   2.1
  9750  -0.1  31.8  320  13  6   6.1   3.4 |   0.2  32.4  325  10  5   7.4   4.1
  9500   0.3  32.5  315  12  6   6.1   3.3 |   0.7  33.3  325  10  5   6.8   3.8
  9250   0.7  33.3  310  11  6   4.3   2.4 |   1.2  34.2  325   9  5   5.6   3.1
  9000   0.9  33.6  310  11  6   3.4   1.9 |   1.6  34.9  325   9  5   5.0   2.8
  8750   1.3  34.3  305  10  5   6.5   3.6 |   2.0  35.6  320  10  5   7.1   3.9
  8500   1.8  35.2  305  10  5   7.4   4.1 |   2.6  36.7  320  10  5   7.5   4.1
  8250   2.4  36.3  305  10  5   7.5   4.1 |   3.1  37.6  320  10  5   7.5   4.1
  8000   2.9  37.2  305  10  5   7.4   4.1 |   3.7  38.7  320  11  6   7.4   4.0
  7750   3.5  38.3  305  11  6   9.3   5.1 |   4.2  39.6  320  12  6   8.1   4.5
  7500   4.2  39.6  310  12  6   7.1   3.9 |   4.8  40.6  320  12  6   6.7   3.7
  7250   4.5  40.1  310  14  7   2.9   1.6 |   5.2  41.4  315  14  7   4.4   2.4
  7000   4.8  40.6  310  17  9   3.9   2.2 |   5.5  41.9  310  16  8   5.4   3.0
  6750   5.0  41.0  310  20 10   1.2   0.6 |   5.8  42.4  310  18 10   2.2   1.2
  6500   4.7  40.5  310  21 11 -10.6  -5.8 |   5.6  42.1  305  20 10  -6.6  -3.6
  6250   3.6  38.5  305  19 10 -13.4  -7.3 |   4.9  40.8  300  17  9  -8.5  -4.7
  6000   2.5  36.5  300  17  9 -21.3 -11.7 |   4.2  39.6  285  16  8 -11.7  -6.4
  5750   0.2  32.4  285  14  7 -36.1 -19.8 |   2.9  37.2  275  13  7 -18.6 -10.2
  5500  -2.5  27.5  270   8  4 -31.6 -17.3 |   1.5  34.7  260   9  4 -17.1  -9.4

           01/24/2015 at 1400 MST          |       01/24/2015 at 1700 MST
                                           |
K index... -18.7  LI... +7.7               | K index... +17.8  LI... +3.6
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.8
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -60.2 -76.4  350  28 15   2.3   1.3 | -59.6 -75.3  005  26 14   3.1   1.7
 45000 -56.6 -69.9  345  31 16   1.5   0.8 | -55.1 -67.2  010  35 18   1.6   0.9
 40000 -54.9 -66.8  345  37 19   1.1   0.6 | -53.4 -64.1  350  40 20   1.1   0.6
 38000 -55.2 -67.4  345  37 19  -2.1  -1.1 | -53.6 -64.5  340  40 21  -2.1  -1.2
 36000 -56.4 -69.5  335  36 19  -2.1  -1.1 | -54.9 -66.8  335  38 19  -2.1  -1.2
 34000 -56.9 -70.4  325  36 18   9.4   5.2 | -55.7 -68.3  325  36 19   6.5   3.6
 32000 -51.3 -60.3  325  35 18   8.3   4.6 | -51.2 -60.2  320  35 18   6.7   3.7
 30000 -46.2 -51.2  325  33 17   9.0   5.0 | -46.7 -52.1  315  34 17   9.5   5.2
 29000 -43.5 -46.3  320  30 16   9.0   5.0 | -43.8 -46.8  315  34 17   9.6   5.3
 28000 -40.8 -41.4  320  28 14   9.0   5.0 | -40.9 -41.6  315  33 17   9.6   5.3
 27000 -38.0 -36.4  315  25 13   9.5   5.2 | -38.1 -36.6  315  33 17   9.1   5.0
 26000 -35.1 -31.2  315  24 13   9.6   5.3 | -35.4 -31.7  320  32 17   8.9   4.9
 25000 -32.2 -26.0  315  23 12   9.6   5.3 | -32.8 -27.0  330  32 17   8.9   4.9
 24000 -29.3 -20.7  315  23 12   9.6   5.3 | -30.1 -22.2  335  33 17   8.5   4.7
 23000 -26.5 -15.7  320  23 12   9.6   5.3 | -27.7 -17.9  335  34 17   7.9   4.4
 22000 -23.6 -10.5  320  24 12   9.6   5.3 | -25.4 -13.7  335  35 18   7.9   4.4
 21000 -20.9  -5.6  320  24 13   5.8   3.2 | -23.0  -9.4  335  36 18   7.8   4.3
 20000 -19.3  -2.7  315  22 12   5.6   3.1 | -20.7  -5.3  325  33 17   7.8   4.3
 19500 -18.4  -1.1  310  22 11   5.6   3.1 | -19.6  -3.3  325  31 16   7.8   4.3
 19000 -17.6   0.3  305  21 11   5.6   3.1 | -18.4  -1.1  320  30 16   7.8   4.3
 18500 -16.8   1.8  300  21 11   5.4   3.0 | -17.3   0.9  315  29 15   5.8   3.2
 18000 -16.0   3.2  290  22 11   5.3   2.9 | -16.6   2.1  315  28 14   4.7   2.6
 17500 -15.1   4.8  285  23 12   5.4   2.9 | -15.9   3.4  320  26 13   4.5   2.5
 17000 -14.3   6.3  285  22 12   5.3   2.9 | -15.3   4.5  320  25 13   3.9   2.2
 16500 -13.6   7.5  290  22 11   5.2   2.9 | -14.7   5.5  325  24 12   3.8   2.1
 16000 -12.3   9.9  295  20 10   6.0   3.3 | -13.5   7.7  330  23 12   6.8   3.7
 15500 -11.4  11.5  300  19 10   6.0   3.3 | -12.5   9.5  330  23 12   6.7   3.7
 15000 -10.5  13.1  305  18  9   5.6   3.1 | -11.5  11.3  335  24 12   7.6   4.2
 14500  -9.7  14.5  305  16  8   5.6   3.1 | -10.4  13.3  335  25 13   7.7   4.2
 14000  -8.8  16.2  310  15  8   6.5   3.6 |  -9.4  15.1  340  26 13   6.4   3.5
 13500  -7.8  18.0  315  14  7   6.5   3.6 |  -8.4  16.9  340  26 14   6.4   3.5
 13000  -6.8  19.8  325  14  7   7.0   3.8 |  -7.5  18.5  345  27 14   6.6   3.6
 12500  -5.8  21.6  330  14  7   7.0   3.8 |  -6.5  20.3  345  27 14   6.6   3.6
 12000  -4.7  23.5  330  15  8   7.7   4.2 |  -5.5  22.1  350  28 14   7.0   3.8
 11500  -3.5  25.7  335  16  8   7.9   4.3 |  -4.5  23.9  350  29 15   7.0   3.8
 11000  -2.3  27.9  340  17  9   9.1   5.0 |  -3.4  25.9  355  30 16   7.8   4.3
 10500  -0.9  30.4  340  18 10  10.5   5.8 |  -2.2  28.0  355  32 17   8.9   4.9
 10250  -0.2  31.6  340  19 10   4.4   2.4 |  -1.7  28.9  355  33 17   3.8   2.1
 10000  -0.1  31.8  340  19 10   5.9   3.2 |  -1.5  29.3  355  34 17   4.7   2.6
  9750   0.8  33.4  340  20 10  12.8   7.0 |  -0.9  30.4  355  35 18  10.2   5.6
  9500   1.7  35.1  335  21 11  11.7   6.4 |  -0.2  31.6  350  35 18   9.1   5.0
  9250   2.5  36.5  335  21 11   9.3   5.1 |   0.5  32.9  350  36 19   8.1   4.4
  9000   3.0  37.4  335  22 11   6.9   3.8 |   1.0  33.8  350  35 18   6.8   3.7
  8750   3.7  38.7  330  23 12   9.0   4.9 |   1.6  34.9  350  34 17   8.0   4.4
  8500   4.3  39.7  325  24 12   9.0   4.9 |   2.2  36.0  350  32 16   7.9   4.3
  8250   4.9  40.8  325  25 13   5.5   3.0 |   2.8  37.0  345  30 15   6.4   3.5
  8000   5.2  41.4  320  27 14   2.9   1.6 |   3.2  37.8  345  28 14   5.4   3.0
  7750   5.3  41.5  315  29 15   1.5   0.8 |   3.7  38.7  340  27 14   5.8   3.2
  7500   5.3  41.5  310  30 16   0.4   0.2 |   4.1  39.4  335  26 13   3.9   2.1
  7250   5.4  41.7  305  30 15   1.3   0.7 |   4.2  39.6  330  26 13   1.6   0.9
  7000   5.4  41.7  305  28 14   1.2   0.6 |   4.3  39.7  320  25 13   1.7   0.9
  6750   5.5  41.9  300  26 13   2.9   1.6 |   4.4  39.9  315  25 13   0.3   0.1
  6500   5.7  42.3  300  23 12   3.2   1.7 |   4.4  39.9  310  24 12   2.2   1.2
  6250   5.8  42.4  300  20 10   0.6   0.3 |   4.7  40.5  310  21 11   3.9   2.1
  6000   5.9  42.6  300  17  9   5.1   2.8 |   5.0  41.0  305  19 10   6.1   3.3
  5750   6.2  43.2  300  14  7  -3.1  -1.7 |   5.5  41.9  305  16  8   1.9   1.1
  5500   4.8  40.6  295   9  5 -30.5 -16.7 |   5.0  41.0  300  11  6 -13.9  -7.6
________________________________________________________________________________

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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