Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 251316
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0616 MST Wednesday, February 25, 2015

This forecast is for Wednesday, February 25, 2015:

If the trigger temperature of 49.2 F/9.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5502 ft MSL (217 ft AGL)

Forecast maximum temperature................... 43.0 F/6.6 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............ 20 mph or less
Height of the -3 thermal index................. 5358 ft MSL (73 ft AGL)
Thermal soaring outlook for Thursday 02/26..... Poor

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Becoming poor by 1400 MST
Height of stable layer (12-18K ft MSL)......... 13159 ft MSL (7874 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 23493 ft MSL (18208 ft AGL)
Wave soaring outlook for Thursday 02/26........ Poor

Remarks... Cold front by early afternoon with snow and northerly winds behind it

Sunrise/Sunset.................... 06:38:33 / 17:45:44 MST
Total possible sunshine........... 11 hr 7 min 11 sec (667 min 11 sec)
Altitude of sun at 12:12:25 MST... 41.26 degrees

Upper air data from rawinsonde observation taken on 02/25/2015 at 0500 MST

Freezing level.................. 8290 ft MSL (3005 ft AGL)
Convective condensation level... 15883 ft MSL (10598 ft AGL)
Lifted condensation level....... 12066 ft MSL (6781 ft AGL)
Lifted index.................... +9.8
K index......................... +9.5

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  -57.7 -71.9   310   54   28  -1.8  -1.0  105.3 221.5    56.5      M    M
 45000  -53.3 -63.9   295   47   24  -0.8  -0.4   87.0 188.5    49.4      M    M
 40000  -52.6 -62.7   305   55   28  -4.6  -2.5   65.1 149.1    38.5      M    M
 38000  -52.7 -62.9   300   55   28  -8.0  -4.4   56.0 132.9    33.4      M    M
 36000  -53.8 -64.8   300   47   24   0.2   0.1   45.8 114.4    27.3      M    M
 34000  -59.0 -74.2   290   52   27   5.9   3.2   29.8  85.7    16.8      M    M
 32000  -54.4 -65.9   300   49   25   8.0   4.4   28.2  82.8    16.0      M    M
 30000  -49.4 -56.9   300   51   26   7.3   4.0   26.0  78.8    14.9      M    M
 29000  -46.6 -51.9   300   52   27   9.2   5.0   25.8  78.5    14.9      M    M
 28000  -43.9 -47.0   300   53   27   8.9   4.9   25.5  77.9    14.9      M    M
 27000  -41.3 -42.3   295   53   27   8.8   4.9   25.0  77.0    14.7      M    M
 26000  -38.6 -37.5   295   54   28   8.8   4.9   24.7  76.4    14.6      M    M
 25000  -36.0 -32.8   295   55   28   8.4   4.6   24.4  75.9    14.5      M    M
 24000  -33.5 -28.3   300   56   29   8.7   4.8   23.8  74.9    14.3      M    M
 23000  -31.7 -25.1   310   58   30   4.9   2.7   22.5  72.4    13.3      M    M
 22000  -30.3 -22.5   310   48   25   1.8   1.0   20.6  69.2    12.0      M    M
 21000  -28.8 -19.8   315   38   20   8.1   4.4   19.0  66.1    10.7      M    M
 20000  -26.4 -15.5   315   38   20   8.3   4.5   18.5  65.2    10.3      M    M
 19500  -25.2 -13.4   315   36   19   8.3   4.5   18.2  64.7    10.1      M    M
 19000  -23.9 -11.0   320   35   18   8.3   4.6   17.9  64.2     9.9      M    M
 18500  -22.7  -8.9   325   33   17   8.6   4.7   17.6  63.8     9.8      M    M
 18000  -21.6  -6.9   325   31   16   7.6   4.2   17.3  63.1     9.5      M    M
 17500  -20.3  -4.5   330   29   15   8.6   4.7   17.1  62.8     9.4      M    M
 17000  -19.0  -2.2   335   27   14   8.7   4.8   16.9  62.5     9.3      M    M
 16500  -17.7   0.1   335   27   14   8.7   4.7   16.7  62.1     9.2      M    M
 16000  -16.4   2.5   330   27   14   8.6   4.7   16.5  61.8     9.0      M    M
 15500  -15.1   4.8   330   26   13   8.1   4.5   16.4  61.4     8.9      M    M
 15000  -13.5   7.7   325   24   12   7.6   4.2   15.8  60.4     8.5      M    M
 14500  -12.3   9.9   320   23   12   7.6   4.2   15.4  59.8     8.2      M    M
 14000  -11.2  11.8   320   22   11   7.4   4.1   15.1  59.2     7.9      M    M
 13500  -10.1  13.8   330   22   11   5.2   2.9   14.7  58.5     7.6      M    M
 13000   -9.7  14.5   340   21   11   4.5   2.5   13.6  56.5     6.6      M    M
 12500   -8.9  16.0   350   18    9   5.5   3.0   12.9  55.3     6.0      M    M
 12000   -8.0  17.6   360   16    8   5.5   3.0   12.3  54.1     5.4      M    M
 11500   -7.2  19.0   345   15    8   5.5   3.0   11.6  52.8     4.8      M    M
 11000   -6.4  20.5   335   15    8   5.4   3.0   10.9  51.6     4.2      M    M
 10500   -5.4  22.3   330   17    9   8.0   4.4   10.3  50.6     3.7      M    M
 10250   -4.8  23.4   330   18    9   9.0   4.9   10.3  50.5     3.6      M    M
 10000   -4.1  24.6   330   19   10   8.6   4.7   10.2  50.3     3.6      M    M
  9750   -3.5  25.7   330   21   11   8.2   4.5   10.1  50.2     3.5      M    M
  9500   -2.9  26.8   325   22   12   8.0   4.4   10.0  49.9     3.4      M    M
  9250   -2.3  27.9   320   24   13   8.1   4.4    9.8  49.7     3.2      M    M
  9000   -1.7  28.9   320   26   13   8.0   4.4    9.7  49.5     3.1      M    M
  8750   -1.1  30.0   320   25   13   8.0   4.4    9.6  49.2     3.0      M    M
  8500   -0.5  31.1   320   25   13   8.0   4.4    9.4  49.0     2.9      M    M
  8250    0.1  32.2   315   24   13   8.0   4.4    9.3  48.8     2.8      M    M
  8000    0.7  33.3   315   24   12   8.0   4.4    9.2  48.5     2.6      M    M
  7750    1.3  34.3   315   24   12   8.0   4.4    9.0  48.3     2.5      M    M
  7500    1.9  35.4   315   25   13   8.0   4.4    8.9  48.0     2.4      M    M
  7250    2.5  36.5   315   25   13   8.0   4.4    8.8  47.8     2.3      M    M
  7000    3.1  37.6   315   25   13   8.1   4.4    8.7  47.6     2.1      M    M
  6750    3.7  38.7   315   23   12   8.0   4.4    8.5  47.3     2.0      M    M
  6500    4.3  39.7   310   22   11   8.3   4.6    8.4  47.1     1.9      M    M
  6250    4.9  40.8   310   20   10   6.9   3.8    8.2  46.8     1.7      M    M
  6000    5.3  41.5   305   18    9   3.9   2.1    7.9  46.2     1.4      M    M
  5750    5.7  42.3   300   14    7   7.9   4.3    7.5  45.5     1.0      M    M
  5500    6.0  42.8   290    9    5  -6.7  -3.7    7.1  44.9     0.6      M    M

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

           02/25/2015 at 0800 MST          |       02/25/2015 at 1100 MST
                                           |
K index... +9.5  LI... +276.7              | K index... +11.2  LI... +276.8
CAPE... 0.0  CIN... -0.8                   | CAPE... 0.0  CIN... -0.4
                                           |
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 -55.3 -67.5  300  37 19   2.0   1.1 | -55.0 -67.0  290  43 22   2.1   1.1
 45000 -52.3 -62.1  300  47 24   2.0   1.1 | -51.9 -61.4  295  52 27   2.1   1.1
 40000 -49.2 -56.6  300  47 24   1.9   1.1 | -49.1 -56.4  295  52 27   1.7   0.9
 38000 -48.9 -56.0  300  48 24  -7.5  -4.1 | -48.6 -55.5  295  52 27  -5.3  -2.9
 36000 -52.9 -63.2  295  52 27  -6.7  -3.7 | -51.4 -60.5  290  58 30  -4.6  -2.5
 34000 -56.9 -70.4  290  58 30  -6.5  -3.6 | -54.1 -65.4  290  65 33  -4.4  -2.4
 32000 -54.7 -66.5  285  60 31   6.9   3.8 | -53.6 -64.5  285  66 34   2.9   1.6
 30000 -50.1 -58.2  285  61 31   7.4   4.1 | -51.8 -61.2  285  65 33   3.0   1.6
 29000 -47.5 -53.5  285  60 31   8.7   4.8 | -50.1 -58.2  285  64 33   7.9   4.3
 28000 -44.9 -48.8  290  60 31   8.7   4.8 | -47.1 -52.8  290  62 32   8.1   4.4
 27000 -42.3 -44.1  290  60 31   8.7   4.8 | -44.7 -48.5  290  61 32   8.1   4.4
 26000 -40.1 -40.2  290  58 30   6.0   3.3 | -42.3 -44.1  290  59 30   7.4   4.1
 25000 -38.3 -36.9  295  56 29   5.9   3.3 | -40.1 -40.2  290  53 27   7.4   4.1
 24000 -36.5 -33.7  300  55 28   6.0   3.3 | -37.9 -36.2  290  48 25   7.4   4.1
 23000 -34.6 -30.3  305  52 27   7.5   4.1 | -35.7 -32.3  290  43 22   7.7   4.2
 22000 -32.3 -26.1  305  49 25   7.5   4.1 | -33.4 -28.1  295  38 20   7.6   4.2
 21000 -30.1 -22.2  305  45 23   7.5   4.1 | -31.1 -24.0  295  34 18   7.7   4.2
 20000 -27.8 -18.0  305  42 22   7.6   4.2 | -28.9 -20.0  295  31 16   7.3   4.0
 19500 -26.7 -16.1  305  40 21   7.6   4.2 | -27.8 -18.0  300  30 15   7.3   4.0
 19000 -25.6 -14.1  305  39 20   7.6   4.2 | -26.7 -16.1  305  29 15   7.3   4.0
 18500 -24.5 -12.1  305  38 19   7.6   4.2 | -25.6 -14.1  305  28 14   7.3   4.0
 18000 -23.3  -9.9  305  36 19   7.2   4.0 | -24.6 -12.3  310  27 14   6.6   3.6
 17500 -22.3  -8.1  305  35 18   7.1   3.9 | -23.6 -10.5  315  27 14   6.3   3.4
 17000 -21.2  -6.2  305  33 17   7.2   3.9 | -22.7  -8.9  320  28 14   6.3   3.5
 16500 -20.1  -4.2  305  32 16   7.5   4.1 | -21.8  -7.2  320  29 15   6.5   3.6
 16000 -19.0  -2.2  305  31 16   7.6   4.2 | -20.8  -5.4  325  30 15   6.5   3.6
 15500 -17.5   0.5  310  30 15   6.6   3.6 | -19.8  -3.6  325  31 16   6.9   3.8
 15000 -16.5   2.3  315  30 15   6.7   3.7 | -18.3  -0.9  325  32 16   6.9   3.8
 14500 -15.5   4.1  320  30 15   7.2   3.9 | -17.3   0.9  330  32 17   6.6   3.6
 14000 -14.4   6.1  325  31 16   7.2   3.9 | -16.3   2.7  330  32 17   6.6   3.6
 13500 -13.4   7.9  330  32 17   7.3   4.0 | -15.4   4.3  330  32 16   6.3   3.4
 13000 -12.3   9.9  330  34 17   7.3   4.0 | -14.4   6.1  330  31 16   6.3   3.5
 12500 -11.1  12.0  330  35 18   8.0   4.4 | -13.5   7.7  330  30 16   6.5   3.5
 12000 -10.0  14.0  330  36 18   8.1   4.4 | -12.6   9.3  335  29 15   6.3   3.5
 11500  -8.9  16.0  335  36 18   6.2   3.4 | -11.5  11.3  335  27 14   7.9   4.4
 11000  -8.0  17.6  335  36 19   6.4   3.5 | -10.4  13.3  335  26 13   7.8   4.3
 10500  -7.0  19.4  335  36 19   6.4   3.5 |  -9.3  15.3  340  24 13   6.6   3.6
 10250  -6.6  20.1  335  36 18   6.3   3.5 |  -8.8  16.2  340  24 12   5.6   3.1
 10000  -6.1  21.0  335  36 18   6.7   3.7 |  -8.4  16.9  340  23 12   9.8   5.4
  9750  -5.6  21.9  330  35 18   6.8   3.7 |  -7.5  18.5  340  22 11  10.9   6.0
  9500  -5.1  22.8  330  34 18   6.5   3.6 |  -6.9  19.6  340  21 11   7.3   4.0
  9250  -4.6  23.7  330  34 18   6.6   3.6 |  -6.3  20.7  340  21 11   8.3   4.6
  9000  -4.1  24.6  330  34 17   6.5   3.5 |  -5.7  21.7  340  20 10   7.6   4.2
  8750  -3.7  25.3  325  33 17   5.0   2.8 |  -5.1  22.8  345  20 10   7.6   4.2
  8500  -3.4  25.9  325  32 17   4.1   2.3 |  -4.6  23.7  345  19 10   7.9   4.4
  8250  -3.1  26.4  320  31 16   4.2   2.3 |  -4.0  24.8  350  18  9   7.8   4.3
  8000  -2.7  27.1  320  30 16   5.8   3.2 |  -3.4  25.9  350  17  9   8.5   4.7
  7750  -2.2  28.0  320  28 14   6.5   3.6 |  -2.7  27.1  350  17  9   7.9   4.3
  7500  -1.8  28.8  320  26 14   5.3   2.9 |  -2.2  28.0  355  16  8   6.8   3.7
  7250  -1.4  29.5  320  25 13   6.2   3.4 |  -1.7  28.9  355  15  8   7.4   4.0
  7000  -0.9  30.4  320  23 12   7.5   4.1 |  -1.1  30.0  355  15  8   8.0   4.4
  6750  -0.3  31.5  320  21 11   7.1   3.9 |  -0.5  31.1  360  14  7   7.6   4.2
  6500   0.2  32.4  320  19 10   6.3   3.4 |   0.0  32.0  005  13  7   6.8   3.7
  6250   0.6  33.1  320  17  9   4.1   2.2 |   0.5  32.9  005  12  6   5.1   2.8
  6000   0.8  33.4  320  14  7   2.6   1.4 |   0.7  33.3  005  10  5   4.1   2.3
  5750   1.0  33.8  320  12  6   2.6   1.4 |   1.0  33.8  005   8  4   4.0   2.2
  5500   0.9  33.6  310   8  4  -6.9  -3.8 |   1.3  34.3  355   5  3   1.0   0.5

           02/25/2015 at 1400 MST          |       02/25/2015 at 1700 MST
                                           |
K index... +17.5  LI... +275.8             | K index... +15.1  LI... +275.0
CAPE... +24.6  CIN... -2.4                 | CAPE... +76.3  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 -54.9 -66.8  300  41 21   1.9   1.1 | -52.3 -62.1  305  46 24   1.0   0.5
 45000 -52.0 -61.6  300  59 30   1.9   1.1 | -50.8 -59.4  300  61 31   1.0   0.5
 40000 -49.4 -56.9  295  56 29   1.6   0.9 | -49.5 -57.1  300  55 28   0.9   0.5
 38000 -48.7 -55.7  295  54 28  -2.2  -1.2 | -49.0 -56.2  300  52 27   0.5   0.2
 36000 -49.8 -57.6  295  55 28  -1.9  -1.0 | -48.7 -55.7  305  51 26   0.4   0.2
 34000 -50.9 -59.6  295  55 28  -1.8  -1.0 | -48.5 -55.3  305  51 26   0.5   0.2
 32000 -51.7 -61.1  290  55 28  -1.0  -0.6 | -49.7 -57.5  300  52 27  -3.6  -1.9
 30000 -52.3 -62.1  285  56 29  -0.8  -0.5 | -51.8 -61.2  295  54 28  -3.6  -2.0
 29000 -51.6 -60.9  285  55 28   7.4   4.0 | -52.1 -61.8  290  55 28   6.8   3.7
 28000 -48.8 -55.8  285  52 27   7.3   4.0 | -49.9 -57.8  290  54 28   5.8   3.2
 27000 -46.7 -52.1  285  49 25   7.3   4.0 | -48.2 -54.8  290  53 27   5.8   3.2
 26000 -44.4 -47.9  285  47 24   7.9   4.3 | -46.3 -51.3  290  52 27   7.5   4.1
 25000 -42.1 -43.8  290  46 23   7.8   4.3 | -44.1 -47.4  290  50 26   7.5   4.1
 24000 -39.7 -39.5  290  44 23   7.8   4.3 | -41.8 -43.2  295  48 25   7.5   4.1
 23000 -37.3 -35.1  295  43 22   9.0   5.0 | -39.6 -39.3  295  46 24   8.1   4.5
 22000 -34.6 -30.3  295  42 21   8.9   4.9 | -37.1 -34.8  295  44 23   8.1   4.5
 21000 -32.0 -25.6  295  40 21   8.9   4.9 | -34.7 -30.5  295  42 22   8.2   4.5
 20000 -29.6 -21.3  300  40 21   7.1   3.9 | -32.3 -26.1  290  39 20   8.2   4.5
 19500 -28.6 -19.5  300  40 21   7.0   3.9 | -31.1 -24.0  290  37 19   8.2   4.5
 19000 -27.5 -17.5  300  40 21   7.1   3.9 | -29.8 -21.6  290  35 18   8.2   4.5
 18500 -26.5 -15.7  305  40 21   7.0   3.9 | -28.6 -19.5  290  33 17   8.2   4.5
 18000 -25.4 -13.7  305  41 21   6.3   3.5 | -27.4 -17.3  290  30 16   7.6   4.2
 17500 -24.6 -12.3  305  40 21   5.7   3.1 | -26.4 -15.5  290  29 15   6.6   3.6
 17000 -23.8 -10.8  310  40 21   5.7   3.1 | -25.4 -13.7  290  27 14   6.6   3.6
 16500 -23.0  -9.4  310  39 20   6.0   3.3 | -24.4 -11.9  290  25 13   7.1   3.9
 16000 -22.1  -7.8  310  38 19   5.9   3.2 | -23.4 -10.1  295  24 12   7.0   3.9
 15500 -21.2  -6.2  310  36 18   6.8   3.7 | -22.4  -8.3  300  22 11   6.9   3.8
 15000 -19.6  -3.3  310  31 16   6.9   3.8 | -20.8  -5.4  305  19 10   6.8   3.8
 14500 -18.6  -1.5  310  29 15   7.2   3.9 | -19.8  -3.6  315  19 10   6.7   3.7
 14000 -17.6   0.3  310  27 14   7.2   3.9 | -18.8  -1.8  320  18  9   6.8   3.7
 13500 -16.5   2.3  315  25 13   7.2   3.9 | -17.9  -0.2  330  18  9   6.2   3.4
 13000 -15.4   4.3  315  23 12   7.2   4.0 | -17.0   1.4  340  18  9   6.2   3.4
 12500 -14.4   6.1  320  22 11   6.8   3.7 | -16.0   3.2  350  19 10   6.6   3.6
 12000 -13.4   7.9  325  21 11   6.9   3.8 | -15.1   4.8  360  20 10   6.7   3.7
 11500 -12.4   9.7  330  20 10   6.5   3.6 | -14.1   6.6  005  22 11   6.0   3.3
 11000 -11.5  11.3  340  20 10   6.6   3.6 | -13.2   8.2  015  23 12   6.1   3.4
 10500 -10.6  12.9  345  20 10   5.9   3.2 | -12.4   9.7  020  25 13   5.3   2.9
 10250 -10.1  13.8  350  20 11   5.2   2.9 | -12.0  10.4  020  26 13   4.7   2.6
 10000  -9.7  14.5  350  21 11   7.9   4.4 | -11.6  11.1  020  27 14   7.5   4.1
  9750  -9.0  15.8  355  21 11   8.5   4.7 | -11.0  12.2  020  27 14   8.7   4.8
  9500  -8.5  16.7  355  22 11   6.1   3.3 | -10.4  13.3  020  27 14   6.8   3.7
  9250  -8.0  17.6  360  22 11   6.9   3.8 |  -9.9  14.2  020  27 14   7.3   4.0
  9000  -7.6  18.3  005  23 12   6.0   3.3 |  -9.4  15.1  020  27 14   7.1   3.9
  8750  -7.1  19.2  005  23 12   6.3   3.4 |  -8.8  16.2  020  26 13   8.3   4.6
  8500  -6.6  20.1  005  22 11   7.2   4.0 |  -8.2  17.2  025  24 13   9.4   5.1
  8250  -6.1  21.0  005  22 11   6.9   3.8 |  -7.5  18.5  025  23 12   9.1   5.0
  8000  -5.6  21.9  010  21 11   8.2   4.5 |  -6.9  19.6  025  22 11   8.9   4.9
  7750  -5.0  23.0  010  20 10   8.0   4.4 |  -6.2  20.8  025  21 11   8.1   4.4
  7500  -4.4  24.1  015  19 10   6.5   3.5 |  -5.7  21.7  025  20 11   7.5   4.1
  7250  -3.9  25.0  015  19 10   7.7   4.2 |  -5.1  22.8  025  20 10   8.0   4.4
  7000  -3.3  26.1  020  17  9   9.2   5.0 |  -4.5  23.9  025  19 10   8.6   4.7
  6750  -2.7  27.1  020  16  8   8.8   4.8 |  -3.9  25.0  025  18  9   8.2   4.5
  6500  -2.0  28.4  025  14  7   8.7   4.8 |  -3.3  26.1  025  18  9   8.2   4.5
  6250  -1.4  29.5  025  13  6   9.9   5.5 |  -2.7  27.1  025  16  8   8.8   4.8
  6000  -0.6  30.9  025  12  6  10.7   5.9 |  -2.1  28.2  025  15  8   9.2   5.1
  5750   0.1  32.2  025  10  5   9.9   5.5 |  -1.4  29.5  025  13  7   8.6   4.7
  5500   0.8  33.4  025   9  5   9.6   5.2 |  -0.8  30.6  020  11  6   7.8   4.3
________________________________________________________________________________

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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