Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 230131
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1831 MST Thursday, January 22, 2015

This forecast is for Friday, January 23, 2015:

If the trigger temperature of 48.4 F/9.1 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 219 ft/min (1.1 m/s)
   Maximum height of thermals.................. 8596 ft MSL (3309 ft AGL)

Forecast maximum temperature................... 47.0 F/8.8 C
Time of trigger temperature.................... 1415 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................. 6853 ft MSL (1566 ft AGL)
Thermal soaring outlook for Saturday 01/24..... Poor

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)................ Neither
Potential height of wave....................... 44747 ft MSL (39460 ft AGL)
Wave soaring outlook for Saturday 01/24........ Poor

Remarks...

Sunrise/Sunset.................... 07:14:33 / 17:07:08 MST
Total possible sunshine........... 9 hr 52 min 35 sec (592 min 35 sec)
Altitude of sun at 12:11:14 MST... 30.91 degrees

Upper air data from numerical model forecast valid on 01/23/2015 at 0500 MST

Freezing level.................. 6011 ft MSL (724 ft AGL)
Additional freezing level....... 7583 ft MSL (2296 ft AGL)
Convective condensation level... 20537 ft MSL (15250 ft AGL)
Lifted condensation level....... 15425 ft MSL (10138 ft AGL)
Lifted index.................... +11.3
K index......................... -0.3

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  -58.3 -72.9   355   20   10   1.5   0.8      M     M       M      M    M
 45000  -56.0 -68.8   360   29   15   1.9   1.0      M     M       M      M    M
 40000  -59.1 -74.4   010   32   16  -2.2  -1.2      M     M       M      M    M
 38000  -59.4 -74.9   010   33   17   2.6   1.4      M     M       M      M    M
 36000  -57.8 -72.0   010   35   18   2.6   1.4      M     M       M      M    M
 34000  -55.5 -67.9   010   36   19   8.7   4.8      M     M       M      M    M
 32000  -50.6 -59.1   010   34   18   8.2   4.5      M     M       M      M    M
 30000  -45.6 -50.1   010   33   17   8.0   4.4   30.6  87.1    16.7      M    M
 29000  -43.2 -45.8   010   32   16   8.1   4.4   29.8  85.7    16.3      M    M
 28000  -40.8 -41.4   015   31   16   8.1   4.4   29.2  84.5    16.0      M    M
 27000  -38.4 -37.1   015   30   16   7.7   4.2   28.7  83.6    15.8      M    M
 26000  -36.2 -33.2   015   29   15   7.1   3.9   27.6  81.6    15.1      M    M
 25000  -34.1 -29.4   015   28   14   7.1   3.9   26.5  79.8    14.5      M    M
 24000  -32.0 -25.6   015   27   14   7.1   3.9   25.6  78.2    13.9      M    M
 23000  -29.8 -21.6   010   25   13   7.4   4.1   24.7  76.4    13.3      M    M
 22000  -27.6 -17.7   010   24   12   7.4   4.1   23.8  74.9    12.8      M    M
 21000  -25.3 -13.5   010   23   12   7.6   4.2   23.1  73.5    12.3      M    M
 20000  -23.0  -9.4   010   24   12   7.7   4.2   22.2  72.0    11.7      M    M
 19500  -21.9  -7.4   005   24   12   7.7   4.2   21.9  71.4    11.4      M    M
 19000  -20.8  -5.4   005   24   13   7.7   4.2   21.5  70.8    11.2      M    M
 18500  -19.6  -3.3   005   25   13   7.1   3.9   21.2  70.2    11.0      M    M
 18000  -18.7  -1.7   005   25   13   6.1   3.4   20.6  69.1    10.5      M    M
 17500  -17.8  -0.0   005   25   13   6.1   3.4   20.0  68.0    10.0      M    M
 17000  -16.5   2.3   010   26   13   6.1   3.4   19.1  66.3     9.2      M    M
 16500  -15.5   4.1   010   26   13   6.1   3.4   18.4  65.2     8.7      M    M
 16000  -14.7   5.5   010   25   13   6.0   3.3   17.8  64.1     8.2      M    M
 15500  -13.8   7.2   010   25   13   6.0   3.3   17.2  62.9     7.6      M    M
 15000  -12.9   8.8   010   25   13   6.0   3.3   16.6  61.8     7.1      M    M
 14500  -12.0  10.4   010   24   13   6.0   3.3   15.9  60.7     6.6      M    M
 14000  -11.1  12.0   005   24   12   6.3   3.4   15.3  59.6     6.0      M    M
 13500  -10.2  13.6   005   23   12   6.3   3.5   14.7  58.5     5.5      M    M
 13000   -9.2  15.4   005   22   11   6.6   3.6   14.2  57.6     5.1      M    M
 12500   -8.1  17.4   360   21   11   6.8   3.7   13.7  56.7     4.7      M    M
 12000   -7.1  19.2   360   21   11   5.4   3.0   13.2  55.7     4.3      M    M
 11500   -6.3  20.7   355   20   10   5.0   2.7   12.4  54.3     3.6      M    M
 11000   -5.6  21.9   355   19   10   4.8   2.6   11.6  52.9     3.0      M    M
 10500   -4.9  23.2   355   18    9   5.0   2.7   10.8  51.5     2.2      M    M
 10250   -4.5  23.9   355   17    9   3.4   1.9   10.4  50.7     1.8      M    M
 10000   -4.3  24.3   355   17    9   3.7   2.0    9.9  49.8     1.3      M    M
  9750   -3.9  25.0   355   16    8   7.3   4.0    9.5  49.2     1.0      M    M
  9500   -3.3  26.1   360   16    8   8.6   4.7    9.4  48.9     0.9      M    M
  9250   -2.7  27.1   005   15    8   6.9   3.8    9.3  48.7     0.7      M    M
  9000   -2.3  27.9   005   15    8   5.4   3.0    9.0  48.2     0.4      M    M
  8750   -1.8  28.8   005   15    7   6.5   3.6    8.7  47.6     0.1      M    M
  8500   -1.3  29.7   005   14    7   6.8   3.7    8.4  47.2    -0.1    209  1.1
  8250   -0.9  30.4   005   13    7   4.9   2.7    8.2  46.7    -0.4    188  1.0
  8000   -0.5  31.1   360   11    6   4.0   2.2    7.7  45.9    -0.8    171  0.9
  7750   -0.2  31.6   355    9    5   4.2   2.3    7.3  45.1    -1.2    154  0.8
  7500    0.1  32.2   345    7    4   3.5   1.9    6.9  44.3    -1.6    137  0.7
  7250    0.3  32.5   335    7    4   2.9   1.6    6.3  43.4    -2.1    123  0.6
  7000    0.5  32.9   330    7    4   3.0   1.6    5.8  42.5    -2.7    109  0.6
  6750    0.7  33.3   325    7    4   2.8   1.6    5.3  41.5    -3.2     96  0.5
  6500    0.8  33.4   315    8    4  -2.3  -1.3    4.6  40.3    -3.9     87  0.4
  6250    0.4  32.7   310   10    5  -3.1  -1.7    3.6  38.4    -5.0     90  0.5
  6000    0.1  32.2   305   11    6 -10.7  -5.9    2.5  36.5    -6.1     92  0.5
  5750   -1.5  29.3   295   10    5 -28.7 -15.8    0.2  32.4    -8.4    132  0.7
  5500   -3.9  25.0   270    7    3 -31.9 -17.5   -2.9  26.8   -11.5    198  1.0

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

           01/23/2015 at 0800 MST          |       01/23/2015 at 1100 MST
                                           |
K index... +6.1  LI... +6.4                | K index... +10.1  LI... +4.9
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.1
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -58.5 -73.3  355  19 10   1.1   0.6 | -58.5 -73.3  340  16  8   1.7   0.9
 45000 -56.8 -70.2  005  27 14   1.5   0.8 | -55.9 -68.6  335  22 11   2.1   1.2
 40000 -59.2 -74.6  360  28 15  -1.7  -0.9 | -58.5 -73.3  330  22 11  -1.8  -1.0
 38000 -59.0 -74.2  005  29 15   2.9   1.6 | -58.5 -73.3  330  23 12   2.3   1.3
 36000 -57.3 -71.1  005  30 15   2.9   1.6 | -57.1 -70.8  335  24 12   2.3   1.3
 34000 -55.2 -67.4  010  30 15   8.2   4.5 | -55.3 -67.5  340  25 13   8.6   4.7
 32000 -50.6 -59.1  005  29 15   7.8   4.3 | -50.4 -58.7  345  23 12   8.2   4.5
 30000 -45.9 -50.6  005  27 14   7.7   4.2 | -45.5 -49.9  350  21 11   7.8   4.3
 29000 -43.6 -46.5  360  27 14   7.7   4.2 | -43.2 -45.8  350  21 11   7.9   4.3
 28000 -41.3 -42.3  360  26 13   7.7   4.2 | -40.2 -40.4  350  21 11   7.9   4.3
 27000 -38.4 -37.1  355  25 13   7.8   4.3 | -37.8 -36.0  355  21 11   7.6   4.2
 26000 -36.1 -33.0  355  24 12   7.8   4.3 | -35.6 -32.1  350  21 11   7.3   4.0
 25000 -33.8 -28.8  350  24 12   7.8   4.3 | -33.5 -28.3  345  21 11   7.3   4.0
 24000 -31.4 -24.5  350  23 12   7.6   4.2 | -31.3 -24.3  340  22 11   7.2   4.0
 23000 -29.2 -20.6  350  22 11   7.4   4.0 | -29.2 -20.6  340  21 11   7.0   3.9
 22000 -27.0 -16.6  345  22 11   7.4   4.0 | -27.1 -16.8  340  21 11   7.0   3.9
 21000 -24.9 -12.8  345  21 11   6.9   3.8 | -25.0 -13.0  340  21 11   6.7   3.7
 20000 -22.9  -9.2  345  21 11   6.8   3.7 | -23.1  -9.6  340  20 10   6.5   3.6
 19500 -21.9  -7.4  350  21 11   6.8   3.7 | -22.1  -7.8  340  19 10   6.6   3.6
 19000 -20.9  -5.6  350  21 11   6.8   3.7 | -21.1  -6.0  340  18 10   6.5   3.6
 18500 -19.9  -3.8  350  22 11   6.6   3.6 | -20.2  -4.4  340  18  9   6.1   3.3
 18000 -18.9  -2.0  355  22 11   6.5   3.6 | -19.4  -2.9  340  18  9   5.7   3.1
 17500 -17.9  -0.2  355  22 11   6.5   3.6 | -18.5  -1.3  340  18  9   5.7   3.1
 17000 -17.0   1.4  355  22 11   6.2   3.4 | -17.6   0.3  345  18  9   6.6   3.6
 16500 -16.1   3.0  360  22 12   6.2   3.4 | -16.7   1.9  345  18  9   6.5   3.6
 16000 -15.2   4.6  360  23 12   6.4   3.5 | -15.7   3.7  345  18  9   6.3   3.5
 15500 -14.3   6.3  360  23 12   6.4   3.5 | -14.8   5.4  345  19 10   6.3   3.5
 15000 -13.3   8.1  360  23 12   6.6   3.6 | -13.9   7.0  345  19 10   6.8   3.7
 14500 -12.3   9.9  360  22 11   6.8   3.7 | -12.8   9.0  350  19 10   7.2   4.0
 14000 -10.8  12.6  360  22 11   6.8   3.7 | -11.2  11.8  350  20 10   6.4   3.5
 13500  -9.8  14.4  355  21 11   6.8   3.8 | -10.3  13.5  350  20 10   6.4   3.5
 13000  -8.8  16.2  355  21 11   6.1   3.4 |  -9.3  15.3  350  21 11   6.4   3.5
 12500  -7.9  17.8  350  20 10   6.0   3.3 |  -8.4  16.9  350  21 11   6.4   3.5
 12000  -7.0  19.4  350  19 10   4.9   2.7 |  -7.5  18.5  350  22 11   5.4   3.0
 11500  -6.3  20.7  345  19 10   4.7   2.6 |  -6.7  19.9  350  21 11   5.3   2.9
 11000  -5.7  21.7  345  18  9   3.7   2.0 |  -6.0  21.2  350  20 10   3.9   2.1
 10500  -5.2  22.6  345  17  9   3.9   2.1 |  -5.4  22.3  350  17  9   4.0   2.2
 10250  -4.9  23.2  345  16  8   1.8   1.0 |  -5.1  22.8  350  16  8   2.1   1.1
 10000  -4.8  23.4  345  16  8   2.7   1.5 |  -5.0  23.0  350  16  8   2.7   1.5
  9750  -4.4  24.1  345  15  8   6.9   3.8 |  -4.6  23.7  350  14  7   6.3   3.4
  9500  -3.9  25.0  350  14  7   7.4   4.0 |  -4.1  24.6  355  13  7   6.6   3.6
  9250  -3.4  25.9  355  14  7   6.6   3.6 |  -3.7  25.3  360  12  6   5.8   3.2
  9000  -2.9  26.8  360  14  7   6.1   3.4 |  -3.2  26.2  005  12  6   5.6   3.1
  8750  -2.4  27.7  005  14  7   7.4   4.1 |  -2.8  27.0  010  11  6   7.9   4.3
  8500  -1.8  28.8  010  14  7   7.7   4.2 |  -2.1  28.2  015  10  5   8.8   4.8
  8250  -1.3  29.7  015  14  7   6.5   3.6 |  -1.5  29.3  020  10  5   8.1   4.4
  8000  -0.8  30.6  010  13  7   6.0   3.3 |  -0.9  30.4  020   9  5   8.0   4.4
  7750  -0.4  31.3  010  12  6   6.3   3.5 |  -0.3  31.5  025   8  4   7.7   4.2
  7500   0.1  32.2  005  10  5   5.6   3.1 |   0.3  32.5  030   7  4   6.7   3.6
  7250   0.5  32.9  355   8  4   4.8   2.7 |   0.7  33.3  020   5  3   6.0   3.3
  7000   0.9  33.6  345   7  4   5.2   2.9 |   1.2  34.2  360   3  2   6.3   3.5
  6750   1.3  34.3  330   6  3   4.1   2.3 |   1.7  35.1  315   2  1   5.9   3.3
  6500   1.4  34.5  320   7  4  -0.5  -0.3 |   2.0  35.6  300   4  2   2.7   1.5
  6250   1.3  34.3  315   9  5   1.0   0.6 |   2.1  35.8  305   6  3   3.2   1.7
  6000   1.2  34.2  310  12  6  -9.8  -5.4 |   2.3  36.1  305   8  4  -3.9  -2.1
  5750  -0.5  31.1  295  10  5 -32.5 -17.8 |   1.3  34.3  295   6  3 -15.7  -8.6
  5500  -3.2  26.2  270   6  3 -35.9 -19.7 |   0.1  32.2  275   4  2 -12.4  -6.8

           01/23/2015 at 1400 MST          |       01/23/2015 at 1700 MST
                                           |
K index... +8.2  LI... +6.3                | K index... +9.5  LI... +6.6
CAPE... 0.0  CIN... -0.7                   | CAPE... 0.0  CIN... -0.5
                                           |
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 -58.3 -72.9  335  20 10   2.1   1.2 | -58.2 -72.8  345  21 11   1.5   0.8
 45000 -55.1 -67.2  330  30 15   2.6   1.4 | -56.0 -68.8  340  31 16   1.7   0.9
 40000 -57.4 -71.3  325  25 13  -1.6  -0.9 | -56.3 -69.3  320  27 14  -0.3  -0.1
 38000 -57.7 -71.9  320  24 12   1.1   0.6 | -56.4 -69.5  305  27 14  -0.0  -0.0
 36000 -57.0 -70.6  315  24 12   1.1   0.6 | -56.4 -69.5  290  29 15  -0.0  -0.0
 34000 -55.9 -68.6  305  24 12   8.1   4.5 | -56.1 -69.0  280  33 17   6.8   3.7
 32000 -51.1 -60.0  310  23 12   8.1   4.5 | -51.6 -60.9  290  28 14   7.4   4.1
 30000 -46.2 -51.2  315  23 12   8.3   4.6 | -47.1 -52.8  295  24 12   8.5   4.6
 29000 -43.8 -46.8  320  22 11   8.2   4.5 | -44.6 -48.3  305  22 11   8.3   4.5
 28000 -40.7 -41.3  325  21 11   8.2   4.5 | -41.5 -42.7  310  21 11   8.3   4.5
 27000 -38.3 -36.9  325  20 10   7.9   4.3 | -39.0 -38.2  320  20 10   8.2   4.5
 26000 -36.0 -32.8  335  20 10   7.6   4.2 | -36.6 -33.9  320  20 10   8.2   4.5
 25000 -33.7 -28.7  340  20 10   7.7   4.2 | -34.2 -29.6  325  19 10   8.2   4.5
 24000 -31.4 -24.5  345  20 10   7.5   4.1 | -31.8 -25.2  325  19 10   8.0   4.4
 23000 -29.3 -20.7  345  20 10   7.1   3.9 | -29.5 -21.1  330  18  9   7.6   4.2
 22000 -27.2 -17.0  345  20 10   7.2   3.9 | -27.2 -17.0  335  18  9   7.6   4.2
 21000 -25.1 -13.2  350  20 11   6.9   3.8 | -25.0 -13.0  340  17  9   6.9   3.8
 20000 -23.0  -9.4  350  20 10   6.9   3.8 | -23.0  -9.4  340  16  8   6.7   3.7
 19500 -22.0  -7.6  350  20 10   6.9   3.8 | -22.0  -7.6  345  16  8   6.7   3.7
 19000 -21.0  -5.8  350  20 10   6.9   3.8 | -21.0  -5.8  345  15  8   6.7   3.7
 18500 -20.0  -4.0  350  19 10   6.7   3.7 | -20.0  -4.0  345  15  8   6.7   3.7
 18000 -19.0  -2.2  345  19 10   6.5   3.6 | -19.0  -2.2  345  15  8   6.8   3.7
 17500 -18.1  -0.6  345  19 10   6.5   3.6 | -18.0  -0.4  345  15  8   6.8   3.7
 17000 -17.1   1.2  345  20 10   6.1   3.3 | -17.1   1.2  345  16  8   6.0   3.3
 16500 -16.2   2.8  340  20 10   6.1   3.4 | -16.2   2.8  345  16  8   6.1   3.3
 16000 -15.3   4.5  340  20 10   5.8   3.2 | -15.4   4.3  345  17  9   5.2   2.9
 15500 -14.5   5.9  335  20 10   5.8   3.2 | -14.6   5.7  345  18  9   5.0   2.8
 15000 -13.6   7.5  335  20 11   5.6   3.1 | -13.9   7.0  345  18 10   5.0   2.8
 14500 -12.8   9.0  335  21 11   5.4   2.9 | -13.2   8.2  340  19 10   5.0   2.8
 14000 -11.6  11.1  335  22 11   5.5   3.0 | -12.0  10.4  340  20 11   4.9   2.7
 13500 -10.8  12.6  335  22 11   5.5   3.0 | -11.3  11.7  340  21 11   4.8   2.7
 13000 -10.0  14.0  335  22 11   5.7   3.2 | -10.5  13.1  335  21 11   5.5   3.0
 12500  -9.1  15.6  340  22 11   5.8   3.2 |  -9.7  14.5  340  22 11   5.7   3.1
 12000  -8.3  17.1  340  22 11   5.3   2.9 |  -8.9  16.0  340  22 11   5.3   2.9
 11500  -7.5  18.5  340  22 11   5.1   2.8 |  -8.1  17.4  340  22 11   5.2   2.8
 11000  -6.7  19.9  340  21 11   5.4   3.0 |  -7.3  18.9  345  22 11   5.6   3.1
 10500  -5.9  21.4  345  20 10   6.0   3.3 |  -6.4  20.5  345  22 11   6.2   3.4
 10250  -5.5  22.1  345  20 10   3.4   1.9 |  -6.0  21.2  350  22 11   3.8   2.1
 10000  -5.3  22.5  345  19 10   4.2   2.3 |  -5.8  21.6  350  22 11   4.2   2.3
  9750  -4.8  23.4  345  19 10   8.5   4.7 |  -5.3  22.5  350  21 11   8.2   4.5
  9500  -4.2  24.4  350  18  9   9.0   5.0 |  -4.7  23.5  355  21 11   8.8   4.9
  9250  -3.5  25.7  350  17  9   6.9   3.8 |  -4.1  24.6  355  21 11   6.6   3.6
  9000  -3.1  26.4  350  16  8   5.4   3.0 |  -3.7  25.3  355  20 10   5.1   2.8
  8750  -2.6  27.3  350  15  8   7.5   4.1 |  -3.2  26.2  355  19 10   8.2   4.5
  8500  -2.0  28.4  350  14  7   8.0   4.4 |  -2.5  27.5  360  18  9   8.8   4.8
  8250  -1.4  29.5  350  13  7   7.5   4.1 |  -2.0  28.4  360  17  9   7.1   3.9
  8000  -0.9  30.4  345  11  6   7.3   4.0 |  -1.5  29.3  360  15  8   6.5   3.5
  7750  -0.3  31.5  345  10  5   7.8   4.3 |  -0.9  30.4  360  14  7   7.9   4.4
  7500   0.3  32.5  340   8  4   7.8   4.3 |  -0.3  31.5  360  12  6   8.1   4.4
  7250   0.8  33.4  340   7  4   7.2   4.0 |   0.2  32.4  360  12  6   6.9   3.8
  7000   1.4  34.5  335   6  3   7.6   4.2 |   0.8  33.4  005  11  5   7.5   4.1
  6750   1.9  35.4  330   6  3   6.6   3.6 |   1.3  34.3  005  10  5   6.4   3.5
  6500   2.3  36.1  330   5  3   2.7   1.5 |   1.7  35.1  010   8  4   4.0   2.2
  6250   2.3  36.1  335   5  2   1.9   1.1 |   1.9  35.4  010   7  4   4.1   2.3
  6000   2.4  36.3  345   4  2  -0.3  -0.2 |   2.2  36.0  015   6  3   1.7   0.9
  5750   2.1  35.8  355   3  2  -5.5  -3.0 |   1.9  35.4  020   4  2  -6.6  -3.6
  5500   1.5  34.7  360   2  1  -5.4  -2.9 |   1.1  34.0  005   1  1 -12.0  -6.6
________________________________________________________________________________

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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