Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 241320
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0620 MST Monday, November 24, 2014

This forecast is for Monday, November 24, 2014:

If the trigger temperature of 38.1 F/3.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 127 ft/min (0.6 m/s)
   Maximum height of thermals.................. 11748 ft MSL (6463 ft AGL)

Forecast maximum temperature................... 41.0 F/5.5 C
Time of trigger temperature.................... 1015 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6240 ft MSL (954 ft AGL)
Thermal soaring outlook for Tuesday 11/25...... 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 PVA
Potential height of wave....................... 23733 ft MSL (18448 ft AGL)
Wave soaring outlook for Tuesday 11/25......... Good

Remarks...

Sunrise/Sunset.................... 06:54:15 / 16:38:08 MST
Total possible sunshine........... 9 hr 43 min 53 sec (583 min 53 sec)
Altitude of sun at 11:46:21 MST... 29.64 degrees

Upper air data from rawinsonde observation taken on 11/24/2014 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 15130 ft MSL (9845 ft AGL)
Lifted condensation level....... 14427 ft MSL (9142 ft AGL)
Lifted index.................... +2.4
K index......................... +6.5

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  -56.2 -69.2   285   48   25  10.2   5.6  109.8 229.6    59.3      M    M
 45000  -49.8 -57.6   295   31   16   6.3   3.5   94.4 201.9    54.3      M    M
 40000  -48.4 -55.1   295   57   29 -25.5 -14.0   73.5 164.3    44.4      M    M
 38000  -49.7 -57.5   290   45   23   2.9   1.6   62.6 144.7    38.4      M    M
 36000  -49.3 -56.7   285   26   14 -12.6  -6.9   54.6 130.3    33.9      M    M
 34000  -47.1 -52.8   320   32   16   3.7   2.1   49.3 120.7    31.1      M    M
 32000  -46.5 -51.7   315   41   21   1.2   0.7   41.8 107.3    26.5      M    M
 30000  -52.0 -61.6   300   53   28   0.4   0.2   25.4  77.7    15.1      M    M
 29000  -51.8 -61.2   310   53   27   4.6   2.5   21.7  71.1    12.6      M    M
 28000  -53.0 -63.4   315   60   31 -11.7  -6.4   16.3  61.4     8.6      M    M
 27000  -52.7 -62.9   315   67   34  -5.3  -2.9   12.9  55.2     6.1      M    M
 26000  -51.1 -60.0   315   62   32  10.2   5.6   11.1  52.0     4.8      M    M
 25000  -48.2 -54.8   315   57   29   9.5   5.2   11.2  52.1     4.9      M    M
 24000  -45.4 -49.7   320   58   30   9.1   5.0   11.0  51.8     4.8      M    M
 23000  -42.7 -44.9   320   59   30   9.8   5.4   10.7  51.3     4.7      M    M
 22000  -39.7 -39.5   325   55   28   9.2   5.1   10.8  51.4     4.7      M    M
 21000  -37.2 -35.0   330   52   27   8.2   4.5   10.3  50.6     4.4      M    M
 20000  -34.5 -30.1   335   49   25   9.4   5.1   10.1  50.1     4.2      M    M
 19500  -33.1 -27.6   335   48   25   9.4   5.1   10.0  50.0     4.2      M    M
 19000  -31.7 -25.1   335   46   24   9.3   5.1    9.9  49.8     4.1      M    M
 18500  -30.3 -22.5   335   45   23   8.5   4.6    9.9  49.7     4.1      M    M
 18000  -29.3 -20.7   335   43   22   6.9   3.8    9.4  48.8     3.7      M    M
 17500  -28.4 -19.1   335   42   22   4.8   2.6    8.7  47.7     3.1      M    M
 17000  -27.7 -17.9   335   41   21   5.5   3.0    7.9  46.1     2.4      M    M
 16500  -26.5 -15.7   330   39   20   9.2   5.0    7.6  45.6     2.2      M    M
 16000  -25.2 -13.4   330   38   20   9.0   4.9    7.5  45.4     2.1      M    M
 15500  -23.8 -10.8   330   37   19   9.0   4.9    7.3  45.1     1.9      M    M
 15000  -21.8  -7.2   335   36   18   9.0   4.9    7.1  44.7     1.8      M    M
 14500  -20.5  -4.9   335   35   18   9.0   4.9    7.0  44.5     1.7      M    M
 14000  -19.1  -2.4   335   34   17   8.9   4.9    6.9  44.3     1.6      M    M
 13500  -17.8  -0.0   330   34   17   8.1   4.4    6.7  44.1     1.4      M    M
 13000  -16.8   1.8   325   34   17   6.8   3.7    6.2  43.2     1.0      M    M
 12500  -15.7   3.7   325   34   17   6.8   3.7    5.8  42.4     0.6      M    M
 12000  -14.7   5.5   320   34   17   6.8   3.7    5.3  41.6     0.2      M    M
 11500  -13.7   7.3   325   31   16   6.8   3.7    4.8  40.7    -0.3    498  2.5
 11000  -12.7   9.1   325   28   15   6.9   3.8    4.4  39.9    -0.7    453  2.3
 10500  -11.7  10.9   315   32   17   7.4   4.0    3.9  39.0    -1.2    408  2.1
 10250  -11.1  12.0   315   34   18   8.8   4.8    3.8  38.8    -1.3    382  1.9
 10000  -10.4  13.3   310   36   19   9.1   5.0    3.7  38.7    -1.4    354  1.8
  9750   -9.7  14.5   310   38   20   9.0   5.0    3.7  38.6    -1.4    327  1.7
  9500   -9.1  15.6   310   38   20   9.1   5.0    3.6  38.5    -1.5    299  1.5
  9250   -8.4  16.9   310   39   20   9.1   5.0    3.6  38.4    -1.6    271  1.4
  9000   -7.7  18.1   310   39   20   9.1   5.0    3.5  38.3    -1.6    244  1.2
  8750   -7.0  19.4   305   39   20   9.1   5.0    3.4  38.2    -1.7    216  1.1
  8500   -6.4  20.5   305   39   20   9.1   5.0    3.4  38.1    -1.7    188  1.0
  8250   -5.7  21.7   300   40   20   9.1   5.0    3.3  38.0    -1.8    161  0.8
  8000   -5.0  23.0   300   40   21   9.1   5.0    3.3  37.9    -1.8    133  0.7
  7750   -4.3  24.3   300   37   19   9.0   5.0    3.2  37.8    -1.9    105  0.5
  7500   -3.6  25.5   300   33   17   9.2   5.1    3.2  37.7    -2.0     77  0.4
  7250   -3.1  26.4   305   30   16   5.1   2.8    3.0  37.5    -2.1     52  0.3
  7000   -2.8  27.0   305   27   14   4.1   2.2    2.5  36.6    -2.6     37  0.2
  6750   -2.3  27.9   305   24   12   8.5   4.7    2.3  36.1    -2.9     15  0.1
  6500   -1.6  29.1   300   21   11   9.7   5.3    2.3  36.1    -2.9      M    M
  6250   -0.9  30.4   300   18    9   8.4   4.6    2.2  36.0    -3.0      M    M
  6000   -0.5  31.1   295   15    8   3.2   1.8    2.0  35.5    -3.2      M    M
  5750   -0.4  31.3   295   10    5   0.7   0.4    1.3  34.3    -3.9      M    M
  5500   -0.3  31.5   295    5    3   0.4   0.2    0.6  33.2    -4.6      M    M

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

           11/24/2014 at 0800 MST          |       11/24/2014 at 1100 MST
                                           |
K index... +11.0  LI... +1.9               | K index... +16.2  LI... +1.8
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 -53.3 -63.9  305  21 11   1.2   0.7 | -53.3 -63.9  295  27 14   2.0   1.1
 45000 -51.5 -60.7  325  25 13   1.2   0.7 | -50.3 -58.5  300  27 14   2.0   1.1
 40000 -48.5 -55.3  325  40 21   2.1   1.2 | -48.4 -55.1  320  33 17   1.0   0.6
 38000 -47.2 -53.0  325  47 24   0.4   0.2 | -47.8 -54.0  330  36 19  -0.4  -0.2
 36000 -48.3 -54.9  320  40 20  -1.9  -1.0 | -48.9 -56.0  325  37 19  -1.8  -1.0
 34000 -49.5 -57.1  310  33 17  -1.9  -1.0 | -49.9 -57.8  325  38 20  -1.8  -1.0
 32000 -50.8 -59.4  310  31 16  -2.6  -1.4 | -50.6 -59.1  325  38 20  -0.7  -0.4
 30000 -52.4 -62.3  315  33 17  -2.6  -1.5 | -51.0 -59.8  330  37 19  -0.7  -0.4
 29000 -53.1 -63.6  315  35 18   0.5   0.3 | -51.2 -60.2  330  36 19   0.7   0.4
 28000 -52.6 -62.7  310  36 18   1.2   0.7 | -50.8 -59.4  320  35 18   0.8   0.5
 27000 -52.3 -62.1  300  37 19   1.2   0.7 | -50.6 -59.1  315  34 18   0.8   0.5
 26000 -51.7 -61.1  295  39 20   7.1   3.9 | -50.2 -58.4  310  34 17   4.9   2.7
 25000 -48.7 -55.7  300  37 19  10.2   5.6 | -48.1 -54.6  305  32 16   7.0   3.9
 24000 -45.6 -50.1  300  35 18  10.2   5.6 | -46.0 -50.8  305  30 15   7.0   3.9
 23000 -42.6 -44.7  305  33 17   9.5   5.2 | -43.8 -46.8  305  28 15   9.2   5.1
 22000 -39.8 -39.6  310  30 16   9.3   5.1 | -40.9 -41.6  310  26 14   9.7   5.3
 21000 -37.0 -34.6  310  27 14   9.3   5.1 | -38.0 -36.4  315  25 13   9.7   5.3
 20000 -34.3 -29.7  315  25 13   8.8   4.8 | -35.2 -31.4  320  23 12   8.9   4.9
 19500 -33.0 -27.4  315  24 12   8.8   4.8 | -33.9 -29.0  320  22 12   8.9   4.9
 19000 -31.7 -25.1  320  22 12   8.8   4.8 | -32.6 -26.7  320  21 11   8.9   4.9
 18500 -30.4 -22.7  320  21 11   8.8   4.8 | -31.2 -24.2  320  21 11   8.9   4.9
 18000 -29.1 -20.4  325  20 10   8.6   4.7 | -29.9 -21.8  320  20 10   8.5   4.7
 17500 -27.8 -18.0  330  20 10   8.2   4.5 | -28.7 -19.7  325  19 10   7.9   4.3
 17000 -26.6 -15.9  330  20 10   8.2   4.5 | -27.6 -17.7  330  19 10   7.9   4.3
 16500 -25.4 -13.7  335  20 10   7.8   4.3 | -26.4 -15.5  335  19 10   7.3   4.0
 16000 -24.3 -11.7  340  21 11   7.9   4.3 | -25.3 -13.5  335  20 10   7.4   4.1
 15500 -23.1  -9.6  340  22 11   7.2   4.0 | -24.3 -11.7  340  20 10   7.3   4.0
 15000 -22.1  -7.8  340  22 12   7.1   3.9 | -23.2  -9.8  340  22 11   7.3   4.0
 14500 -21.0  -5.8  345  23 12   7.0   3.9 | -22.1  -7.8  345  23 12   7.4   4.1
 14000 -19.5  -3.1  345  26 13   6.8   3.7 | -20.4  -4.7  345  24 12   7.5   4.1
 13500 -18.4  -1.1  350  28 15   8.3   4.5 | -19.3  -2.7  345  25 13   7.9   4.3
 13000 -17.2   1.0  350  31 16   8.0   4.4 | -18.1  -0.6  350  26 13   7.9   4.3
 12500 -15.9   3.4  345  34 17   9.5   5.2 | -17.0   1.4  350  28 14   7.7   4.2
 12000 -14.5   5.9  345  36 19   9.5   5.2 | -15.8   3.6  350  30 15   7.7   4.2
 11500 -13.1   8.4  345  38 19   9.0   5.0 | -14.6   5.7  350  32 16   8.4   4.6
 11000 -11.7  10.9  340  39 20   9.2   5.1 | -13.4   7.9  345  34 17   8.3   4.6
 10500 -10.5  13.1  335  39 20   7.3   4.0 | -12.2  10.0  345  34 18   8.0   4.4
 10250 -10.0  14.0  335  39 20   6.7   3.7 | -11.6  11.1  345  34 17   6.8   3.7
 10000  -9.4  15.1  335  39 20  10.0   5.5 | -11.0  12.2  345  33 17  11.6   6.3
  9750  -8.5  16.7  330  39 20  10.1   5.5 | -10.0  14.0  345  32 16  12.5   6.9
  9500  -8.0  17.6  325  39 20   6.6   3.6 |  -9.3  15.3  340  31 16   8.2   4.5
  9250  -7.4  18.7  325  39 20   7.8   4.3 |  -8.6  16.5  340  30 16   9.8   5.4
  9000  -6.9  19.6  320  39 20   6.5   3.5 |  -7.9  17.8  340  29 15   7.8   4.3
  8750  -6.5  20.3  320  38 20   5.7   3.1 |  -7.4  18.7  340  28 14   7.2   3.9
  8500  -6.0  21.2  315  38 19   6.3   3.4 |  -6.8  19.8  340  27 14   8.2   4.5
  8250  -5.6  21.9  310  37 19   6.1   3.3 |  -6.2  20.8  340  26 13   8.0   4.4
  8000  -5.1  22.8  310  36 19   6.7   3.7 |  -5.6  21.9  340  24 12   8.1   4.5
  7750  -4.6  23.7  305  34 17   6.0   3.3 |  -5.0  23.0  340  22 11   8.6   4.7
  7500  -4.2  24.4  305  31 16   4.6   2.5 |  -4.4  24.1  335  19 10   8.7   4.8
  7250  -3.8  25.2  305  29 15   6.1   3.4 |  -3.7  25.3  335  17  9   9.6   5.3
  7000  -3.3  26.1  305  27 14   8.4   4.6 |  -2.9  26.8  335  17  9  11.0   6.0
  6750  -2.7  27.1  300  24 13   7.3   4.0 |  -2.2  28.0  335  16  8   9.3   5.1
  6500  -2.2  28.0  300  22 11   5.7   3.1 |  -1.5  29.3  335  15  8   9.0   5.0
  6250  -1.8  28.8  300  20 10   5.0   2.8 |  -0.8  30.6  335  15  8  10.8   5.9
  6000  -1.5  29.3  300  17  9   4.5   2.5 |   0.0  32.0  335  14  7  10.8   5.9
  5750  -1.2  29.8  295  14  7   3.7   2.0 |   0.9  33.6  335  14  7  11.0   6.1
  5500  -1.0  30.2  290  10  5  -1.0  -0.6 |   1.8  35.2  335  13  7  14.0   7.7

           11/24/2014 at 1400 MST          |       11/24/2014 at 1700 MST
                                           |
K index... +16.5  LI... +0.3               | K index... +14.6  LI... +0.4
CAPE... 0.0  CIN... -3.6                   | CAPE... 0.0  CIN... -9.2
                                           |
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 -54.6 -66.3  320  24 12   2.2   1.2 | -55.1 -67.2  325  27 14   2.7   1.5
 45000 -51.3 -60.3  310  34 17   2.2   1.2 | -50.9 -59.6  320  41 21   2.7   1.5
 40000 -49.0 -56.2  315  35 18   1.3   0.7 | -50.0 -58.0  330  43 22   0.2   0.1
 38000 -48.3 -54.9  320  35 18  -0.4  -0.2 | -49.9 -57.8  330  44 23  -0.4  -0.2
 36000 -49.4 -56.9  330  37 19  -2.0  -1.1 | -50.5 -58.9  340  46 24  -1.0  -0.5
 34000 -50.6 -59.1  335  39 20  -2.0  -1.1 | -51.1 -60.0  345  49 25  -1.0  -0.5
 32000 -50.8 -59.4  335  40 21   1.1   0.6 | -51.1 -60.0  345  50 26   0.6   0.3
 30000 -50.1 -58.2  335  40 21   1.1   0.6 | -50.7 -59.3  350  50 26   0.7   0.4
 29000 -49.8 -57.6  330  39 20   0.8   0.5 | -50.2 -58.4  350  49 25   3.3   1.8
 28000 -49.5 -57.1  325  36 18   0.9   0.5 | -49.2 -56.6  350  46 24   3.3   1.8
 27000 -49.3 -56.7  320  33 17   0.9   0.5 | -48.2 -54.8  350  43 22   3.3   1.8
 26000 -48.9 -56.0  315  31 16   3.4   1.9 | -47.2 -53.0  350  40 21   2.1   1.1
 25000 -47.5 -53.5  310  33 17   4.8   2.6 | -46.8 -52.2  350  36 18   1.6   0.9
 24000 -46.0 -50.8  305  34 18   4.8   2.6 | -46.3 -51.3  350  31 16   1.6   0.9
 23000 -44.5 -48.1  300  36 18   8.2   4.5 | -45.5 -49.9  350  28 14   8.3   4.5
 22000 -41.7 -43.1  305  34 17   9.1   5.0 | -42.7 -44.9  350  28 14   9.4   5.2
 21000 -39.0 -38.2  305  32 16   9.1   5.0 | -39.8 -39.6  350  28 14   9.4   5.2
 20000 -36.3 -33.3  310  30 15   8.9   4.9 | -37.2 -35.0  350  28 15   8.5   4.7
 19500 -35.0 -31.0  310  30 15   8.9   4.9 | -35.9 -32.6  350  28 15   8.5   4.7
 19000 -33.7 -28.7  305  29 15   8.9   4.9 | -34.6 -30.3  350  29 15   8.5   4.7
 18500 -32.3 -26.1  305  29 15   8.9   4.9 | -33.4 -28.1  345  29 15   8.5   4.7
 18000 -31.0 -23.8  305  28 15   8.7   4.8 | -32.1 -25.8  345  29 15   8.3   4.5
 17500 -29.7 -21.5  305  28 14   8.5   4.7 | -30.9 -23.6  345  29 15   8.2   4.5
 17000 -28.5 -19.3  305  27 14   8.5   4.7 | -29.7 -21.5  340  29 15   8.3   4.6
 16500 -27.3 -17.1  310  27 14   8.0   4.4 | -28.3 -18.9  340  29 15   9.1   5.0
 16000 -26.1 -15.0  315  27 14   8.0   4.4 | -27.0 -16.6  340  29 15   9.2   5.0
 15500 -24.9 -12.8  320  28 14   8.0   4.4 | -25.7 -14.3  340  30 15   8.2   4.5
 15000 -23.7 -10.7  325  29 15   8.1   4.4 | -23.8 -10.8  340  30 15   8.2   4.5
 14500 -21.9  -7.4  330  30 16   8.1   4.4 | -22.6  -8.7  345  31 16   8.1   4.5
 14000 -20.7  -5.3  330  31 16   8.1   4.5 | -21.4  -6.5  345  32 17   8.1   4.4
 13500 -19.5  -3.1  335  31 16   8.1   4.5 | -20.3  -4.5  345  32 17   7.9   4.4
 13000 -18.3  -0.9  335  30 16   8.1   4.5 | -19.1  -2.4  350  32 16   8.2   4.5
 12500 -17.1   1.2  335  30 15   8.1   4.5 | -17.8  -0.0  350  32 17   8.9   4.9
 12000 -15.9   3.4  335  29 15   8.2   4.5 | -16.5   2.3  345  33 17   8.9   4.9
 11500 -14.6   5.7  335  29 15   8.4   4.6 | -15.1   4.8  345  34 17   9.1   5.0
 11000 -13.4   7.9  335  29 15   8.4   4.6 | -13.8   7.2  345  34 17   9.2   5.1
 10500 -12.1  10.2  340  28 15   8.3   4.5 | -12.4   9.7  345  34 17   9.6   5.3
 10250 -11.5  11.3  340  28 14   9.3   5.1 | -11.7  10.9  340  33 17   9.3   5.1
 10000 -10.9  12.4  340  28 14   5.6   3.1 | -11.1  12.0  340  33 17   5.6   3.1
  9750 -10.6  12.9  340  27 14   6.5   3.6 | -10.7  12.7  340  33 17   8.3   4.5
  9500  -9.8  14.4  340  26 13  10.9   6.0 |  -9.8  14.4  340  32 17  13.0   7.1
  9250  -9.1  15.6  340  24 13   9.7   5.3 |  -8.9  16.0  340  32 16  10.6   5.8
  9000  -8.4  16.9  345  23 12   9.0   4.9 |  -8.2  17.2  340  31 16   8.0   4.4
  8750  -7.7  18.1  345  22 11   9.3   5.1 |  -7.6  18.3  340  31 16   8.8   4.8
  8500  -7.0  19.4  345  21 11  10.4   5.7 |  -6.9  19.6  340  30 15  10.8   5.9
  8250  -6.2  20.8  345  20 11  10.2   5.6 |  -6.1  21.0  340  29 15   9.2   5.0
  8000  -5.5  22.1  345  20 10  10.5   5.8 |  -5.5  22.1  340  29 15   8.1   4.5
  7750  -4.7  23.5  345  20 10   9.7   5.3 |  -4.9  23.2  340  28 14   8.4   4.6
  7500  -4.0  24.8  345  19 10   9.1   5.0 |  -4.2  24.4  340  27 14   8.6   4.7
  7250  -3.3  26.1  345  19 10   9.8   5.4 |  -3.6  25.5  345  26 13   8.9   4.9
  7000  -2.5  27.5  345  19 10  10.3   5.7 |  -2.9  26.8  345  25 13   9.2   5.1
  6750  -1.8  28.8  345  19 10   9.8   5.4 |  -2.3  27.9  345  24 13   8.3   4.6
  6500  -1.0  30.2  350  18  9  10.1   5.5 |  -1.7  28.9  350  23 12   7.6   4.2
  6250  -0.3  31.5  350  18  9  10.8   5.9 |  -1.1  30.0  350  21 11   7.5   4.1
  6000   0.5  32.9  350  17  9  10.5   5.8 |  -0.5  31.1  350  19 10   9.0   5.0
  5750   1.3  34.3  350  17  9  10.9   6.0 |   0.1  32.2  350  17  9   5.1   2.8
  5500   2.2  36.0  350  15  8  13.8   7.6 |  -0.0  32.0  350  12  6  -6.5  -3.6
________________________________________________________________________________

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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