Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 230050
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1750 MST Saturday, November 22, 2014

This forecast is for Sunday, November 23, 2014:

If the trigger temperature of 42.5 F/5.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8553 ft MSL (3266 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 opaque middle
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 6384 ft MSL (1097 ft AGL)
Thermal soaring outlook for Monday 11/24....... 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 PVA
Potential height of wave....................... 19596 ft MSL (14309 ft AGL)
Wave soaring outlook for Monday 11/24.......... Poor

Remarks... None

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 numerical model forecast valid on 11/23/2014 at 0500 MST

Freezing level.................. 5636 ft MSL (349 ft AGL)
Convective condensation level... 8579 ft MSL (3292 ft AGL)
Lifted condensation level....... 8553 ft MSL (3266 ft AGL)
Lifted index.................... +4.8
K index......................... +18.9

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  -59.7 -75.5   275   30   16   5.8   3.2      M     M       M      M    M
 45000  -50.9 -59.6   275   47   24   6.2   3.4      M     M       M      M    M
 40000  -46.7 -52.1   285   51   26   2.7   1.5      M     M       M      M    M
 38000  -45.3 -49.5   285   53   27   0.9   0.5      M     M       M      M    M
 36000  -44.7 -48.5   280   57   29   0.9   0.5      M     M       M      M    M
 34000  -44.2 -47.6   275   61   32   0.9   0.5      M     M       M      M    M
 32000  -43.8 -46.8   270   56   29   0.7   0.4      M     M       M      M    M
 30000  -43.4 -46.1   255   51   26   0.5   0.3      M     M       M      M    M
 29000  -42.7 -44.9   250   48   25   2.8   1.5   31.9  89.5    20.4      M    M
 28000  -41.9 -43.4   245   45   23   2.8   1.5   29.1  84.4    18.5      M    M
 27000  -41.0 -41.8   240   42   22   2.8   1.5   26.5  79.7    16.6      M    M
 26000  -40.0 -40.0   235   40   21   6.0   3.3   24.2  75.5    15.0      M    M
 25000  -38.2 -36.8   235   41   21   5.9   3.2   22.6  72.6    14.0      M    M
 24000  -36.4 -33.5   230   41   21   5.9   3.2   21.2  70.1    13.0      M    M
 23000  -34.7 -30.5   225   41   21   4.7   2.6   19.7  67.5    12.0      M    M
 22000  -33.4 -28.1   240   34   18   4.6   2.5   17.7  63.9    10.5      M    M
 21000  -32.0 -25.6   260   30   15   4.6   2.5   15.9  60.6     9.1      M    M
 20000  -30.2 -22.4   275   28   14   8.6   4.7   14.6  58.3     8.1      M    M
 19500  -28.9 -20.0   280   27   14   8.5   4.6   14.4  57.9     7.9      M    M
 19000  -27.7 -17.9   285   26   13   8.5   4.6   14.1  57.4     7.7      M    M
 18500  -26.4 -15.5   285   25   13   8.5   4.6   13.9  57.1     7.6      M    M
 18000  -25.2 -13.4   295   25   13   8.0   4.4   13.8  56.8     7.5      M    M
 17500  -24.2 -11.6   295   25   13   6.1   3.4   13.2  55.8     7.0      M    M
 17000  -22.8  -9.0   300   25   13   6.7   3.6   12.3  54.2     6.3      M    M
 16500  -21.7  -7.1   305   25   13   7.3   4.0   11.9  53.4     5.9      M    M
 16000  -20.6  -5.1   305   24   12   7.3   4.0   11.5  52.7     5.6      M    M
 15500  -19.4  -2.9   305   24   12   8.8   4.8   11.2  52.2     5.4      M    M
 15000  -18.1  -0.6   305   24   12   8.8   4.8   11.0  51.9     5.2      M    M
 14500  -16.9   1.6   310   23   12   7.7   4.2   10.8  51.4     5.0      M    M
 14000  -15.8   3.6   310   23   12   7.8   4.3   10.5  50.8     4.7      M    M
 13500  -14.6   5.7   310   22   12   7.3   4.0   10.1  50.2     4.4      M    M
 13000  -13.6   7.5   310   23   12   7.2   4.0    9.7  49.5     4.0      M    M
 12500  -12.4   9.7   310   23   12   8.1   4.5    9.3  48.8     3.7      M    M
 12000  -11.2  11.8   310   21   11   8.5   4.7    9.1  48.4     3.4      M    M
 11500  -10.1  13.8   315   20   10   6.4   3.5    8.8  47.9     3.2      M    M
 11000   -9.2  15.4   315   21   11   5.8   3.2    8.2  46.7     2.6      M    M
 10500   -8.3  17.1   315   21   11   6.6   3.6    7.6  45.7     2.0      M    M
 10250   -7.8  18.0   320   20   11   6.8   3.8    7.4  45.3     1.8      M    M
 10000   -7.3  18.9   320   20   10   6.6   3.6    7.1  44.8     1.5      M    M
  9750   -6.9  19.6   320   21   11   6.4   3.5    6.9  44.4     1.3      M    M
  9500   -6.4  20.5   325   21   11   6.5   3.6    6.6  43.9     1.0      M    M
  9250   -5.9  21.4   330   21   11   6.4   3.5    6.3  43.4     0.8      M    M
  9000   -5.5  22.1   335   21   11   6.8   3.7    6.1  43.0     0.5      M    M
  8750   -5.0  23.0   335   21   11   6.1   3.3    5.9  42.5     0.3      M    M
  8500   -4.6  23.7   345   22   11   5.4   3.0    5.5  41.9    -0.1    211  1.1
  8250   -4.2  24.4   350   22   12   5.2   2.8    5.2  41.3    -0.4    192  1.0
  8000   -3.8  25.2   355   23   12   6.8   3.7    4.9  40.7    -0.8    173  0.9
  7750   -3.2  26.2   360   25   13   6.4   3.5    4.7  40.4    -0.9    149  0.8
  7500   -2.9  26.8   360   25   13   4.6   2.5    4.3  39.7    -1.3    131  0.7
  7250   -2.5  27.5   005   26   13   4.9   2.7    3.9  39.1    -1.7    113  0.6
  7000   -2.2  28.0   010   27   14   5.8   3.2    3.6  38.4    -2.1     95  0.5
  6750   -1.7  28.9   010   26   13   5.5   3.0    3.3  38.0    -2.4     74  0.4
  6500   -1.4  29.5   015   25   13   4.3   2.3    2.9  37.2    -2.8     57  0.3
  6250   -1.1  30.0   015   23   12   4.9   2.7    2.5  36.5    -3.2     39  0.2
  6000   -0.7  30.7   020   20   10   5.1   2.8    2.2  35.9    -3.5     21  0.1
  5750   -0.3  31.5   020   17    9   5.8   3.2    1.8  35.3    -3.9      1  0.0
  5500    0.2  32.4   020   12    6   8.2   4.5    1.6  34.9    -4.1      M    M

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

           11/23/2014 at 0800 MST          |       11/23/2014 at 1100 MST
                                           |
K index... +12.5  LI... -0.4               | K index... +6.6  LI... -0.6
CAPE... +20.0  CIN... -25.0                | CAPE... +52.9  CIN... -41.4
                                           |
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 -59.2 -74.6  245  29 15   4.6   2.5 | -57.6 -71.7  250  32 17   2.4   1.3
 45000 -51.9 -61.4  245  35 18   4.8   2.6 | -53.8 -64.8  260  39 20   2.2   1.2
 40000 -46.6 -51.9  280  45 23   3.5   1.9 | -47.3 -53.1  280  47 24   4.5   2.5
 38000 -44.7 -48.5  285  50 26   1.6   0.9 | -44.9 -48.8  285  51 26   2.2   1.2
 36000 -43.7 -46.7  280  51 26   1.7   0.9 | -43.5 -46.3  280  51 26   2.3   1.3
 34000 -42.7 -44.9  280  52 27   1.6   0.9 | -42.1 -43.8  280  52 27   2.2   1.2
 32000 -42.2 -44.0  280  47 24   0.4   0.2 | -41.9 -43.4  280  48 25  -0.4  -0.2
 30000 -42.0 -43.6  275  41 21   0.4   0.2 | -42.1 -43.8  285  42 22  -0.4  -0.2
 29000 -41.7 -43.1  275  38 20   1.1   0.6 | -42.2 -44.0  285  39 20  -0.2  -0.1
 28000 -41.4 -42.5  275  35 18   1.1   0.6 | -42.2 -44.0  285  35 18  -0.1  -0.1
 27000 -41.1 -42.0  275  33 17   1.1   0.6 | -42.3 -44.1  285  31 16  -0.1  -0.1
 26000 -40.7 -41.3  270  30 15   2.3   1.3 | -42.3 -44.1  285  27 14   1.4   0.8
 25000 -39.9 -39.8  270  27 14   2.7   1.5 | -41.6 -42.9  285  25 13   2.3   1.3
 24000 -39.0 -38.2  265  24 12   2.7   1.5 | -40.9 -41.6  285  22 11   2.3   1.3
 23000 -38.2 -36.8  260  22 11   3.6   2.0 | -40.2 -40.4  285  20 10   4.0   2.2
 22000 -37.0 -34.6  270  20 10   4.1   2.3 | -38.7 -37.7  290  19 10   5.1   2.8
 21000 -35.8 -32.4  280  19 10   4.2   2.3 | -37.1 -34.8  290  18  9   5.2   2.8
 20000 -34.0 -29.2  290  20 10   9.3   5.1 | -35.2 -31.4  290  18 10   9.2   5.1
 19500 -32.7 -26.9  295  22 11   9.0   4.9 | -33.9 -29.0  290  20 10   9.0   4.9
 19000 -31.3 -24.3  295  24 12   8.9   4.9 | -32.5 -26.5  295  21 11   9.0   4.9
 18500 -30.0 -22.0  300  26 13   9.0   4.9 | -31.2 -24.2  295  23 12   9.0   4.9
 18000 -28.7 -19.7  305  28 14   9.0   5.0 | -29.8 -21.6  295  24 12   9.0   4.9
 17500 -27.3 -17.1  305  30 15   9.4   5.2 | -28.5 -19.3  295  25 13   9.2   5.1
 17000 -25.9 -14.6  310  31 16   9.5   5.2 | -27.1 -16.8  295  26 13   9.2   5.1
 16500 -24.5 -12.1  310  32 16   9.0   5.0 | -25.7 -14.3  300  26 13   9.1   5.0
 16000 -22.5  -8.5  315  32 16   9.0   4.9 | -24.4 -11.9  300  26 13   9.1   5.0
 15500 -21.2  -6.2  315  32 16   8.0   4.4 | -23.0  -9.4  305  26 13   9.0   4.9
 15000 -20.0  -4.0  315  31 16   8.2   4.5 | -21.0  -5.8  310  27 14   9.0   4.9
 14500 -18.9  -2.0  315  30 16   7.5   4.1 | -19.7  -3.5  310  27 14   8.3   4.6
 14000 -17.7   0.1  315  29 15   7.5   4.1 | -18.5  -1.3  315  29 15   8.4   4.6
 13500 -16.6   2.1  315  28 14   7.6   4.2 | -17.2   1.0  315  30 15   8.6   4.7
 13000 -15.5   4.1  315  27 14   7.7   4.2 | -16.0   3.2  320  30 16   8.6   4.7
 12500 -14.4   6.1  315  27 14   7.5   4.1 | -14.7   5.5  320  31 16   8.1   4.5
 12000 -13.3   8.1  315  27 14   7.4   4.1 | -13.5   7.7  320  30 16   8.2   4.5
 11500 -12.2  10.0  315  26 13   7.6   4.2 | -12.3   9.9  320  29 15   7.6   4.2
 11000 -11.1  12.0  315  22 12   7.8   4.3 | -11.2  11.8  320  28 15   7.7   4.2
 10500 -10.0  14.0  310  20 10   6.8   3.7 | -10.2  13.6  320  27 14   6.7   3.7
 10250  -9.5  14.9  310  20 10   6.5   3.5 |  -9.7  14.5  320  26 13   6.2   3.4
 10000  -9.0  15.8  315  19 10   7.6   4.2 |  -9.2  15.4  320  25 13   8.2   4.5
  9750  -8.4  16.9  310  18  9   8.0   4.4 |  -8.5  16.7  320  24 12   9.1   5.0
  9500  -7.9  17.8  315  17  9   7.1   3.9 |  -7.9  17.8  315  23 12   7.7   4.3
  9250  -7.4  18.7  315  17  9   7.5   4.1 |  -7.3  18.9  315  22 12   8.2   4.5
  9000  -6.8  19.8  320  16  8   6.6   3.6 |  -6.7  19.9  315  22 11   7.9   4.3
  8750  -6.4  20.5  320  16  8   6.5   3.6 |  -6.1  21.0  315  21 11   8.2   4.5
  8500  -5.9  21.4  320  15  8   7.3   4.0 |  -5.5  22.1  310  20 10   8.7   4.8
  8250  -5.3  22.5  325  15  8   6.9   3.8 |  -4.9  23.2  310  18  9   8.1   4.5
  8000  -4.8  23.4  325  14  7   7.8   4.3 |  -4.3  24.3  310  17  9   9.9   5.4
  7750  -4.2  24.4  330  14  7   7.4   4.1 |  -3.5  25.7  305  15  8   9.2   5.1
  7500  -3.8  25.2  330  13  7   6.3   3.5 |  -2.9  26.8  305  14  7   6.9   3.8
  7250  -3.3  26.1  330  13  6   6.6   3.6 |  -2.4  27.7  300  13  6   7.9   4.3
  7000  -2.8  27.0  335  12  6   7.4   4.1 |  -1.8  28.8  295  11  6   9.9   5.4
  6750  -2.3  27.9  330  10  5   6.2   3.4 |  -1.0  30.2  290  10  5   9.6   5.3
  6500  -1.9  28.6  330   8  4   4.2   2.3 |  -0.4  31.3  285   9  4   7.8   4.3
  6250  -1.6  29.1  325   6  3   6.1   3.3 |   0.2  32.4  275   8  4   9.7   5.3
  6000  -1.1  30.0  300   4  2   7.4   4.1 |   1.0  33.8  275   7  4  11.4   6.2
  5750  -0.6  30.9  250   3  2   7.4   4.0 |   1.8  35.2  270   7  3   9.9   5.5
  5500   0.0  32.0  225   4  2   9.6   5.3 |   2.5  36.5  270   6  3  10.9   6.0

           11/23/2014 at 1400 MST          |       11/23/2014 at 1700 MST
                                           |
K index... +14.4  LI... +0.5               | K index... +11.5  LI... -0.6
CAPE... +4.8  CIN... -28.1                 | CAPE... +76.3  CIN... -10.4
                                           |
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 -57.3 -71.1  265  33 17   2.2   1.2 | -55.8 -68.4  270  32 16   1.7   1.0
 45000 -54.1 -65.4  275  49 25   2.2   1.2 | -53.1 -63.6  280  42 21   1.8   1.0
 40000 -46.9 -52.4  280  46 24   4.9   2.7 | -47.6 -53.7  285  48 25   3.9   2.1
 38000 -44.3 -47.7  280  44 23   1.1   0.6 | -45.4 -49.7  290  50 26   1.7   0.9
 36000 -43.6 -46.5  285  47 24   1.3   0.7 | -44.5 -48.1  290  49 25   1.4   0.8
 34000 -42.8 -45.0  290  49 25   1.3   0.7 | -43.7 -46.7  295  48 25   1.4   0.8
 32000 -43.0 -45.4  290  48 25  -1.2  -0.6 | -44.2 -47.6  300  47 24  -1.9  -1.1
 30000 -43.7 -46.7  295  44 23  -1.2  -0.7 | -45.3 -49.5  305  46 24  -1.9  -1.0
 29000 -44.0 -47.2  295  42 22  -0.3  -0.1 | -45.6 -50.1  310  45 23   1.1   0.6
 28000 -44.1 -47.4  295  38 20  -0.3  -0.2 | -45.3 -49.5  310  43 22   1.0   0.5
 27000 -44.2 -47.6  295  34 17  -0.3  -0.2 | -45.0 -49.0  310  41 21   1.0   0.5
 26000 -44.3 -47.7  295  30 15   1.3   0.7 | -44.8 -48.6  310  38 20   1.7   0.9
 25000 -43.6 -46.5  300  26 13   2.5   1.4 | -43.9 -47.0  310  36 19   3.0   1.6
 24000 -42.8 -45.0  305  22 11   2.5   1.4 | -43.0 -45.4  305  34 18   3.0   1.6
 23000 -42.0 -43.6  310  18  9   5.4   2.9 | -42.1 -43.8  305  32 16   4.3   2.3
 22000 -39.8 -39.6  315  18 10   7.4   4.0 | -40.3 -40.5  300  30 16   6.4   3.5
 21000 -37.6 -35.7  320  19 10   7.4   4.1 | -38.4 -37.1  295  29 15   6.4   3.5
 20000 -35.3 -31.5  325  21 11   9.0   4.9 | -36.3 -33.3  295  28 14   8.1   4.5
 19500 -34.0 -29.2  320  23 12   8.9   4.9 | -35.1 -31.2  300  28 15   8.0   4.4
 19000 -32.6 -26.7  320  25 13   8.9   4.9 | -33.9 -29.0  305  29 15   8.0   4.4
 18500 -31.3 -24.3  320  26 14   8.9   4.9 | -32.7 -26.9  305  29 15   8.0   4.4
 18000 -30.0 -22.0  320  28 14   8.8   4.8 | -31.5 -24.7  310  30 16   8.0   4.4
 17500 -28.7 -19.7  320  29 15   8.5   4.6 | -30.4 -22.7  310  32 17   7.9   4.3
 17000 -27.4 -17.3  320  30 15   8.5   4.7 | -29.2 -20.6  315  35 18   7.9   4.3
 16500 -26.2 -15.2  320  31 16   8.2   4.5 | -28.0 -18.4  315  37 19   7.8   4.3
 16000 -25.0 -13.0  320  31 16   8.2   4.5 | -26.2 -15.2  315  40 21   7.8   4.3
 15500 -23.8 -10.8  320  32 17   8.0   4.4 | -25.1 -13.2  320  41 21   7.7   4.2
 15000 -22.6  -8.7  320  33 17   7.9   4.4 | -23.9 -11.0  320  43 22   7.7   4.2
 14500 -21.4  -6.5  320  33 17   8.1   4.4 | -22.7  -8.9  325  44 22   8.4   4.6
 14000 -19.6  -3.3  320  32 16   8.3   4.6 | -21.5  -6.7  325  44 22   8.3   4.6
 13500 -18.4  -1.1  320  31 16   7.9   4.3 | -20.3  -4.5  325  43 22   8.5   4.6
 13000 -17.2   1.0  320  31 16   7.9   4.3 | -19.0  -2.2  325  42 22   8.5   4.7
 12500 -16.1   3.0  320  30 15   8.0   4.4 | -17.7   0.1  330  41 21   8.7   4.7
 12000 -14.9   5.2  320  29 15   8.0   4.4 | -16.5   2.3  330  39 20   8.6   4.7
 11500 -13.7   7.3  320  27 14   8.0   4.4 | -15.2   4.6  330  38 20   9.0   5.0
 11000 -12.5   9.5  320  26 13   8.1   4.5 | -13.8   7.2  330  37 19   9.2   5.1
 10500 -11.3  11.7  320  24 13   7.4   4.1 | -12.6   9.3  330  35 18   7.7   4.3
 10250 -10.8  12.6  320  23 12   6.7   3.7 | -12.0  10.4  330  35 18   7.2   4.0
 10000 -10.3  13.5  320  23 12   9.6   5.3 | -11.4  11.5  330  34 18   9.8   5.4
  9750  -9.4  15.1  315  21 11  10.8   5.9 | -10.6  12.9  330  34 17  10.3   5.7
  9500  -8.7  16.3  315  20 10   8.8   4.8 | -10.0  14.0  330  33 17   7.9   4.4
  9250  -8.1  17.4  315  19 10   9.3   5.1 |  -9.3  15.3  335  32 16   8.7   4.8
  9000  -7.4  18.7  315  18  9   9.4   5.1 |  -8.7  16.3  335  31 16   8.2   4.5
  8750  -6.7  19.9  315  18  9   9.7   5.3 |  -8.1  17.4  335  30 16   8.0   4.4
  8500  -5.9  21.4  315  17  9   9.8   5.4 |  -7.5  18.5  335  30 15   8.1   4.4
  8250  -5.2  22.6  315  17  9   9.6   5.3 |  -6.9  19.6  340  29 15   8.0   4.4
  8000  -4.5  23.9  315  17  9  10.3   5.7 |  -6.3  20.7  340  28 14   8.8   4.8
  7750  -3.7  25.3  315  16  8  10.3   5.6 |  -5.7  21.7  340  27 14   8.5   4.7
  7500  -3.0  26.6  315  16  8   9.4   5.2 |  -5.1  22.8  340  26 13   7.7   4.2
  7250  -2.3  27.9  315  16  8   9.8   5.4 |  -4.5  23.9  345  25 13   7.8   4.3
  7000  -1.5  29.3  315  15  8  10.4   5.7 |  -4.0  24.8  345  24 12   7.1   3.9
  6750  -0.7  30.7  315  15  8   9.9   5.5 |  -3.5  25.7  345  22 11   7.9   4.3
  6500  -0.0  32.0  315  15  8   9.1   5.0 |  -2.8  27.0  345  21 11   8.9   4.9
  6250   0.7  33.3  315  15  7  10.3   5.7 |  -2.2  28.0  345  19 10   9.3   5.1
  6000   1.5  34.7  315  14  7  11.4   6.2 |  -1.5  29.3  345  16  8   9.9   5.4
  5750   2.3  36.1  315  13  7  10.5   5.7 |  -0.8  30.6  345  14  7   8.9   4.9
  5500   3.1  37.6  315  12  6  10.8   5.9 |  -0.2  31.6  340  11  6   8.5   4.6
________________________________________________________________________________

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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