Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 231314
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0614 MST Sunday, November 23, 2014

This forecast is for Sunday, November 23, 2014:

If the trigger temperature of 44.9 F/7.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7468 ft MSL (2183 ft AGL)

Forecast maximum temperature................... 41.0 F/5.5 C
Time of trigger temperature.................... None
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................. None
Thermal soaring outlook for Monday 11/24....... Fair

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Becoming poor by 1100
Height of stable layer (12-18K ft MSL)......... 12189 ft MSL (6904 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 14408 ft MSL (9123 ft AGL)
Wave soaring outlook for Monday 11/24.......... Fair

Remarks...

Sunrise/Sunset.................... 06:53:10 / 16:38:38 MST
Total possible sunshine........... 9 hr 45 min 28 sec (585 min 28 sec)
Altitude of sun at 11:46:04 MST... 29.85 degrees

Upper air data from rawinsonde observation taken on 11/23/2014 at 0500 MST

Freezing level.................. 6396 ft MSL (1111 ft AGL)
Convective condensation level... 12970 ft MSL (7685 ft AGL)
Lifted condensation level....... 10482 ft MSL (5197 ft AGL)
Lifted index.................... +5.6
K index......................... +14.1

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  -57.6 -71.7   265   54   28   4.8   2.7  103.7 218.6    56.5      M    M
 45000  -50.4 -58.7   285   49   25   6.2   3.4   91.0 195.8    52.6      M    M
 40000  -48.1 -54.6   265   72   37   6.8   3.7   71.4 160.5    43.4      M    M
 38000  -47.0 -52.6   265   57   29   0.7   0.4   64.3 147.7    39.7      M    M
 36000  -46.2 -51.2   265   59   30   4.3   2.4   56.8 134.2    35.6      M    M
 34000  -44.5 -48.1   265   62   32  -0.2  -0.1   49.8 121.6    31.7      M    M
 32000  -48.3 -54.9   245   60   31   6.1   3.4   36.3  97.3    22.7      M    M
 30000  -45.4 -49.7   240   45   23   0.7   0.4   32.3  90.1    20.4      M    M
 29000  -45.2 -49.4   245   49   25   0.6   0.3   28.7  83.6    17.9      M    M
 28000  -44.9 -48.8   245   43   22  -1.1  -0.6   25.2  77.3    15.4      M    M
 27000  -46.4 -51.5   240   37   19   4.5   2.5   19.5  67.1    11.2      M    M
 26000  -43.9 -47.0   240   31   16   9.0   4.9   19.0  66.1    11.0      M    M
 25000  -41.1 -42.0   240   31   16   9.3   5.1   18.8  65.8    10.9      M    M
 24000  -38.3 -36.9   240   32   16   9.3   5.1   18.6  65.4    10.9      M    M
 23000  -35.5 -31.9   240   32   16   9.0   4.9   18.4  65.2    10.9      M    M
 22000  -32.8 -27.0   245   32   16   9.0   4.9   18.1  64.5    10.7      M    M
 21000  -30.1 -22.2   250   32   16   9.0   4.9   17.8  64.0    10.6      M    M
 20000  -27.4 -17.3   255   32   16   8.9   4.9   17.6  63.7    10.6      M    M
 19500  -26.1 -15.0   255   31   16   8.7   4.7   17.4  63.4    10.5      M    M
 19000  -24.8 -12.6   255   29   15   8.7   4.8   17.2  63.0    10.4      M    M
 18500  -23.5 -10.3   255   28   14   8.6   4.7   17.0  62.7    10.3      M    M
 18000  -22.3  -8.1   255   26   13   4.2   2.3   16.8  62.2    10.1      M    M
 17500  -21.8  -7.2   260   26   13   5.1   2.8   15.6  60.1     9.1      M    M
 17000  -21.2  -6.2   265   26   14   4.7   2.6   14.7  58.5     8.4      M    M
 16500  -19.8  -3.6   275   27   14   9.6   5.3   13.8  56.9     7.6      M    M
 16000  -18.4  -1.1   280   28   14   9.1   5.0   13.7  56.7     7.6      M    M
 15500  -17.1   1.2   285   29   15   9.1   5.0   13.6  56.4     7.5      M    M
 15000  -15.8   3.6   290   29   15   8.0   4.4   13.4  56.1     7.4      M    M
 14500  -14.6   5.7   290   30   16   7.8   4.3   13.1  55.6     7.2      M    M
 14000  -13.5   7.7   295   31   16   6.7   3.7   12.7  54.8     6.8      M    M
 13500  -12.6   9.3   295   29   15   6.8   3.7   12.1  53.9     6.3      M    M
 13000  -11.6  11.1   295   27   14   6.7   3.7   11.7  53.0     5.9      M    M
 12500  -10.6  12.9   290   25   13   5.7   3.1   11.2  52.2     5.5      M    M
 12000  -10.5  13.1   290   23   12   1.1   0.6    9.8  49.6     4.1      M    M
 11500   -9.6  14.7   290   20   10   7.7   4.2    9.2  48.6     3.6      M    M
 11000   -8.4  16.9   285   17    9   7.6   4.2    8.9  48.0     3.3      M    M
 10500   -7.3  18.9   305   14    7   7.6   4.2    8.5  47.4     3.0      M    M
 10250   -6.8  19.8   315   13    7   7.6   4.2    8.4  47.1     2.8      M    M
 10000   -6.2  20.8   325   13    7   7.7   4.2    8.2  46.8     2.6      M    M
  9750   -5.6  21.9   325   13    7   7.4   4.0    8.0  46.5     2.5      M    M
  9500   -5.1  22.8   335   14    7   6.7   3.7    7.8  46.1     2.3      M    M
  9250   -4.6  23.7   345   16    8   7.1   3.9    7.6  45.7     2.0      M    M
  9000   -4.0  24.8   350   18    9   9.0   4.9    7.5  45.4     1.9      M    M
  8750   -3.3  26.1   355   19   10   9.9   5.4    7.5  45.4     1.9      M    M
  8500   -2.6  27.3   360   21   11  10.0   5.5    7.5  45.4     1.9      M    M
  8250   -1.8  28.8   360   22   12   8.9   4.9    7.5  45.4     1.9      M    M
  8000   -1.1  30.0   005   24   12  13.2   7.2    7.5  45.5     1.9      M    M
  7750   -0.4  31.3   005   26   13  -2.9  -1.6    7.5  45.5     1.9      M    M
  7500   -1.4  29.5   010   27   14 -15.2  -8.4    5.6  42.1     0.2      M    M
  7250   -1.9  28.6   010   29   15   0.7   0.4    4.4  39.9    -1.0    133  0.7
  7000   -1.5  29.3   010   31   16   7.7   4.2    4.0  39.2    -1.4    114  0.6
  6750   -0.9  30.4   010   28   15   8.2   4.5    3.9  39.0    -1.5     88  0.4
  6500   -0.3  31.5   015   26   13   7.9   4.3    3.8  38.8    -1.6     63  0.3
  6250    0.3  32.5   015   23   12   8.5   4.7    3.6  38.6    -1.8     37  0.2
  6000    1.0  33.8   020   20   10   9.2   5.1    3.6  38.5    -1.8     10  0.1
  5750    1.6  34.9   025   15    8   9.3   5.1    3.6  38.4    -1.9      M    M
  5500    2.3  36.1   040   10    5   9.0   4.9    3.5  38.3    -2.0      M    M

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

           11/23/2014 at 0800 MST          |       11/23/2014 at 1100 MST
                                           |
K index... +6.2  LI... +3.0                | K index... +7.4  LI... +2.5
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 -57.1 -70.8  270  33 17   4.5   2.5 | -55.1 -67.2  265  42 22   3.4   1.9
 45000 -50.3 -58.5  270  44 22   4.7   2.6 | -49.8 -57.6  270  45 23   3.4   1.9
 40000 -47.2 -53.0  275  49 25   1.9   1.0 | -46.0 -50.8  280  57 30   2.5   1.3
 38000 -46.1 -51.0  275  50 26   2.0   1.1 | -44.7 -48.5  280  61 32   0.2   0.1
 36000 -44.9 -48.8  270  49 25   1.9   1.1 | -44.4 -47.9  280  55 28   0.4   0.2
 34000 -43.6 -46.5  265  47 24   2.1   1.1 | -44.1 -47.4  275  49 25   0.4   0.2
 32000 -43.9 -47.0  265  42 22  -1.1  -0.6 | -44.3 -47.7  275  40 21  -0.6  -0.3
 30000 -44.5 -48.1  265  36 19  -1.1  -0.6 | -44.7 -48.5  265  31 16  -0.5  -0.3
 29000 -44.4 -47.9  260  33 17   1.4   0.8 | -44.6 -48.3  265  27 14   1.1   0.6
 28000 -44.0 -47.2  250  31 16   1.5   0.8 | -44.2 -47.6  260  24 12   1.1   0.6
 27000 -43.5 -46.3  245  29 15   1.5   0.8 | -43.9 -47.0  255  21 11   1.1   0.6
 26000 -42.9 -45.2  235  28 15   4.6   2.5 | -43.5 -46.3  255  18  9   2.8   1.6
 25000 -41.3 -42.3  230  29 15   5.4   2.9 | -42.4 -44.3  260  19 10   3.7   2.0
 24000 -39.7 -39.5  230  31 16   5.4   2.9 | -41.3 -42.3  260  20 10   3.7   2.0
 23000 -38.1 -36.6  225  32 16   6.8   3.7 | -40.1 -40.2  265  21 11   6.6   3.6
 22000 -35.9 -32.6  240  29 15   7.3   4.0 | -37.7 -35.9  275  23 12   8.0   4.4
 21000 -33.7 -28.7  250  29 15   7.3   4.0 | -35.3 -31.5  285  26 14   8.0   4.4
 20000 -31.5 -24.7  265  27 14   7.6   4.2 | -32.9 -27.2  290  29 15   7.9   4.3
 19500 -30.3 -22.5  270  26 13   7.6   4.2 | -31.7 -25.1  295  29 15   7.9   4.3
 19000 -29.2 -20.6  280  25 13   7.6   4.2 | -30.5 -22.9  300  30 15   7.9   4.3
 18500 -28.1 -18.6  290  25 13   7.6   4.2 | -29.3 -20.7  305  31 16   7.9   4.3
 18000 -26.9 -16.4  300  25 13   7.6   4.2 | -28.2 -18.8  310  32 16   8.0   4.4
 17500 -25.8 -14.4  305  27 14   7.4   4.1 | -26.9 -16.4  310  31 16   8.6   4.7
 17000 -24.7 -12.5  310  28 15   7.3   4.0 | -25.6 -14.1  315  31 16   8.6   4.7
 16500 -22.9  -9.2  310  30 15   8.5   4.7 | -24.4 -11.9  315  30 16   7.6   4.2
 16000 -21.6  -6.9  310  30 15   8.5   4.6 | -22.7  -8.9  320  30 16   7.6   4.2
 15500 -20.4  -4.7  310  30 15   8.0   4.4 | -21.7  -7.1  320  30 16   6.8   3.7
 15000 -19.2  -2.6  310  29 15   8.2   4.5 | -20.7  -5.3  320  30 16   6.9   3.8
 14500 -18.1  -0.6  310  29 15   6.8   3.7 | -19.6  -3.3  325  30 15   6.7   3.7
 14000 -17.1   1.2  315  29 15   6.9   3.8 | -18.6  -1.5  325  29 15   6.8   3.7
 13500 -16.2   2.8  320  29 15   6.0   3.3 | -17.7   0.1  325  29 15   6.3   3.4
 13000 -15.3   4.5  320  29 15   5.9   3.2 | -16.8   1.8  330  29 15   6.2   3.4
 12500 -14.5   5.9  325  29 15   6.1   3.3 | -15.8   3.6  330  28 15   6.6   3.6
 12000 -13.6   7.5  330  30 15   6.1   3.3 | -14.8   5.4  335  29 15   6.5   3.6
 11500 -12.6   9.3  335  30 16   6.4   3.5 | -13.8   7.2  335  29 15   7.9   4.3
 11000 -11.6  11.1  340  31 16   6.5   3.6 | -12.6   9.3  340  30 15   8.2   4.5
 10500 -10.6  12.9  345  32 16   6.7   3.7 | -11.4  11.5  340  30 16   6.9   3.8
 10250 -10.1  13.8  345  32 16   6.2   3.4 | -10.9  12.4  345  30 16   6.5   3.6
 10000  -9.6  14.7  350  32 16   8.0   4.4 | -10.4  13.3  345  30 16   8.1   4.4
  9750  -9.0  15.8  350  32 16   8.5   4.7 |  -9.7  14.5  345  30 16   8.9   4.9
  9500  -8.4  16.9  350  32 17   7.0   3.8 |  -9.1  15.6  345  30 15   7.9   4.3
  9250  -7.9  17.8  355  32 17   7.2   3.9 |  -8.5  16.7  350  29 15   8.1   4.5
  9000  -7.3  18.9  355  33 17   7.8   4.3 |  -7.9  17.8  350  29 15   8.3   4.5
  8750  -6.7  19.9  355  33 17   8.0   4.4 |  -7.3  18.9  350  28 14   8.3   4.6
  8500  -6.2  20.8  355  33 17   7.5   4.1 |  -6.7  19.9  350  27 14   8.2   4.5
  8250  -5.6  21.9  360  33 17   7.4   4.0 |  -6.1  21.0  350  26 13   8.0   4.4
  8000  -5.0  23.0  360  33 17   8.6   4.7 |  -5.5  22.1  350  25 13   8.8   4.8
  7750  -4.4  24.1  360  33 17   7.6   4.2 |  -4.8  23.4  350  22 11   8.7   4.8
  7500  -3.9  25.0  360  32 16   5.6   3.1 |  -4.3  24.3  350  21 11   7.6   4.2
  7250  -3.5  25.7  360  31 16   6.2   3.4 |  -3.7  25.3  355  19 10   8.6   4.7
  7000  -3.1  26.4  360  29 15   6.2   3.4 |  -3.0  26.6  355  18  9  10.6   5.8
  6750  -2.6  27.3  360  27 14   6.5   3.6 |  -2.2  28.0  355  18  9  10.2   5.6
  6500  -2.1  28.2  360  24 13   6.5   3.6 |  -1.5  29.3  355  17  9   8.9   4.9
  6250  -1.6  29.1  360  22 11   7.4   4.0 |  -0.8  30.6  355  17  9  10.5   5.8
  6000  -1.1  30.0  360  18 10   8.3   4.5 |   0.1  32.2  355  16  8  11.9   6.5
  5750  -0.5  31.1  355  15  8   8.1   4.4 |   0.9  33.6  355  15  8  10.2   5.6
  5500   0.1  32.2  355  11  5   9.2   5.0 |   1.7  35.1  355  14  7  11.5   6.3

           11/23/2014 at 1400 MST          |       11/23/2014 at 1700 MST
                                           |
K index... +12.8  LI... +1.1               | K index... +15.7  LI... +0.2
CAPE... 0.0  CIN... -0.4                   | CAPE... +3.5  CIN... -2.1
                                           |
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 -55.6 -68.1  260  36 18   3.1   1.7 | -55.7 -68.3  265  39 20   3.3   1.8
 45000 -51.0 -59.8  260  47 24   3.1   1.7 | -50.7 -59.3  265  43 22   3.3   1.8
 40000 -45.9 -50.6  280  54 28   3.3   1.8 | -46.8 -52.2  285  50 26   2.5   1.4
 38000 -44.2 -47.6  285  57 29  -0.1  -0.1 | -45.4 -49.7  290  54 28   1.0   0.5
 36000 -44.1 -47.4  285  53 27   0.2   0.1 | -45.0 -49.0  290  52 27   0.6   0.3
 34000 -44.0 -47.2  285  50 26   0.2   0.1 | -44.7 -48.5  290  50 26   0.5   0.3
 32000 -45.0 -49.0  285  44 23  -2.8  -1.5 | -45.4 -49.7  290  45 23  -2.1  -1.2
 30000 -46.7 -52.1  285  37 19  -2.9  -1.6 | -46.7 -52.1  290  40 21  -2.1  -1.1
 29000 -46.8 -52.2  280  34 18   3.0   1.6 | -46.9 -52.4  295  38 20   2.8   1.5
 28000 -45.9 -50.6  280  33 17   3.1   1.7 | -46.1 -51.0  295  38 19   2.5   1.4
 27000 -45.0 -49.0  275  33 17   3.1   1.7 | -45.4 -49.7  300  37 19   2.5   1.4
 26000 -44.0 -47.2  275  32 17   3.2   1.8 | -44.6 -48.3  300  37 19   2.8   1.5
 25000 -43.1 -45.6  270  34 18   3.3   1.8 | -43.7 -46.7  300  38 20   3.3   1.8
 24000 -42.1 -43.8  270  36 18   3.3   1.8 | -42.7 -44.9  300  40 20   3.3   1.8
 23000 -41.0 -41.8  270  37 19   5.9   3.3 | -41.7 -43.1  300  41 21   4.2   2.3
 22000 -38.8 -37.8  275  39 20   7.3   4.0 | -40.0 -40.0  295  43 22   5.6   3.1
 21000 -36.7 -34.1  280  40 21   7.3   4.0 | -38.4 -37.1  290  45 23   5.6   3.1
 20000 -34.4 -29.9  290  40 20   8.0   4.4 | -36.5 -33.7  285  46 23   8.4   4.6
 19500 -33.2 -27.8  290  37 19   8.0   4.4 | -35.2 -31.4  290  44 23   8.2   4.5
 19000 -32.0 -25.6  295  35 18   8.0   4.4 | -34.0 -29.2  295  43 22   8.2   4.5
 18500 -30.8 -23.4  300  33 17   8.0   4.4 | -32.8 -27.0  295  42 21   8.2   4.5
 18000 -29.6 -21.3  300  30 16   8.1   4.5 | -31.6 -24.9  300  41 21   8.2   4.5
 17500 -28.4 -19.1  305  28 15   8.6   4.7 | -30.3 -22.5  305  40 21   8.5   4.7
 17000 -27.1 -16.8  310  27 14   8.7   4.8 | -29.0 -20.2  310  41 21   8.5   4.7
 16500 -25.9 -14.6  310  26 14   7.5   4.1 | -27.2 -17.0  310  41 21   8.3   4.6
 16000 -24.8 -12.6  315  29 15   7.5   4.1 | -25.9 -14.6  315  40 21   8.3   4.6
 15500 -23.6 -10.5  315  31 16   7.6   4.2 | -24.7 -12.5  315  39 20   8.2   4.5
 15000 -22.5  -8.5  320  33 17   7.7   4.2 | -23.5 -10.3  315  37 19   8.2   4.5
 14500 -20.8  -5.4  320  35 18   7.8   4.3 | -22.2  -8.0  320  36 18   8.5   4.7
 14000 -19.6  -3.3  325  35 18   7.8   4.3 | -21.0  -5.8  320  35 18   8.5   4.7
 13500 -18.5  -1.3  325  35 18   7.9   4.3 | -19.7  -3.5  320  33 17   8.7   4.8
 13000 -17.3   0.9  330  34 18   7.9   4.3 | -18.4  -1.1  320  32 16   8.8   4.8
 12500 -16.2   2.8  330  33 17   7.8   4.3 | -17.2   1.0  320  30 16   8.1   4.4
 12000 -15.0   5.0  330  32 16   7.8   4.3 | -16.0   3.2  320  29 15   8.1   4.4
 11500 -13.8   7.2  335  30 16   8.0   4.4 | -14.8   5.4  320  28 14   7.8   4.3
 11000 -12.7   9.1  335  29 15   8.1   4.5 | -13.6   7.5  325  27 14   7.9   4.3
 10500 -11.6  11.1  340  29 15   6.8   3.7 | -12.6   9.3  325  26 14   7.0   3.8
 10250 -11.1  12.0  340  28 15   6.4   3.5 | -12.0  10.4  325  26 13   6.4   3.5
 10000 -10.6  12.9  340  28 14   8.4   4.6 | -11.5  11.3  325  25 13   8.9   4.9
  9750  -9.8  14.4  345  27 14   8.8   4.8 | -10.8  12.6  325  25 13   9.3   5.1
  9500  -9.3  15.3  345  26 13   7.0   3.9 | -10.2  13.6  325  25 13   7.1   3.9
  9250  -8.8  16.2  350  25 13   7.3   4.0 |  -9.7  14.5  325  24 12   7.7   4.2
  9000  -8.2  17.2  350  24 12   8.1   4.4 |  -9.1  15.6  330  24 12   7.7   4.2
  8750  -7.6  18.3  355  23 12   9.5   5.2 |  -8.5  16.7  330  24 12   8.5   4.7
  8500  -6.8  19.8  355  22 11   9.7   5.3 |  -7.8  18.0  335  23 12   8.8   4.8
  8250  -6.1  21.0  355  21 11   9.4   5.2 |  -7.2  19.0  335  23 12   8.5   4.7
  8000  -5.4  22.3  355  21 11  10.6   5.8 |  -6.5  20.3  335  23 12  10.9   6.0
  7750  -4.6  23.7  355  20 11  10.4   5.7 |  -5.6  21.9  340  22 12  10.6   5.8
  7500  -3.9  25.0  355  20 10   9.0   4.9 |  -4.9  23.2  340  22 11   8.4   4.6
  7250  -3.2  26.2  355  20 10   9.7   5.3 |  -4.3  24.3  340  22 11   9.4   5.2
  7000  -2.4  27.7  355  20 10  10.4   5.7 |  -3.5  25.7  340  21 11  10.1   5.6
  6750  -1.7  28.9  355  20 10   9.8   5.4 |  -2.8  27.0  345  20 10   9.7   5.3
  6500  -1.0  30.2  355  19 10   9.1   5.0 |  -2.1  28.2  345  19 10   9.4   5.1
  6250  -0.3  31.5  355  19 10  10.4   5.7 |  -1.4  29.5  345  18  9  10.1   5.5
  6000   0.6  33.1  355  18  9  11.5   6.3 |  -0.6  30.9  345  16  8  10.5   5.8
  5750   1.4  34.5  355  17  9   9.9   5.4 |   0.2  32.4  345  14  7   9.5   5.2
  5500   2.1  35.8  355  16  8  11.3   6.2 |   0.8  33.4  345  12  6   8.2   4.5
________________________________________________________________________________

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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