Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 051302
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0602 MST Thursday, March 5, 2015

This forecast is for Thursday, March 5, 2015:

If the trigger temperature of 39.0 F/3.9 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 254 ft/min (1.3 m/s)
   Maximum height of thermals.................. 10068 ft MSL (4761 ft AGL)

Forecast maximum temperature................... 40.0 F/4.9 C
Time of trigger temperature.................... 1315 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7061 ft MSL (1754 ft AGL)
Thermal soaring outlook for Friday 03/06....... Poor

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1700 MST)......... Becoming poor
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 26459 ft MSL (21152 ft AGL)
Wave soaring outlook for Friday 03/06.......... Poor

Remarks...

Sunrise/Sunset.................... 06:26:45 / 17:54:32 MST
Total possible sunshine........... 11 hr 27 min 47 sec (687 min 47 sec)
Altitude of sun at 12:10:52 MST... 44.30 degrees

Upper air data from numerical model forecast valid on 03/05/2015 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 18342 ft MSL (13035 ft AGL)
Lifted condensation level....... 14631 ft MSL (9325 ft AGL)
Lifted index.................... +9.2
K index......................... -9.4

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  -56.4 -69.5   280   44   23   3.2   1.7      M     M       M      M    M
 45000  -51.4 -60.5   280   39   20   3.3   1.8      M     M       M      M    M
 40000  -51.2 -60.2   295   39   20  -0.2  -0.1      M     M       M      M    M
 38000  -51.5 -60.7   295   39   20  -1.6  -0.9      M     M       M      M    M
 36000  -52.4 -62.3   300   39   20  -1.5  -0.8      M     M       M      M    M
 34000  -53.3 -63.9   300   38   20  -1.5  -0.8      M     M       M      M    M
 32000  -52.6 -62.7   310   37   19   1.9   1.0      M     M       M      M    M
 30000  -51.3 -60.3   325   36   19   3.1   1.7      M     M       M      M    M
 29000  -49.5 -57.1   330   37   19   6.7   3.6   23.3  74.0    14.3      M    M
 28000  -47.5 -53.5   335   39   20   6.6   3.6   22.1  71.7    13.5      M    M
 27000  -45.5 -49.9   340   40   21   6.7   3.7   21.0  69.7    12.8      M    M
 26000  -43.3 -45.9   340   41   21   7.9   4.3   20.0  68.1    12.2      M    M
 25000  -40.9 -41.6   345   41   21   7.9   4.4   19.3  66.7    11.8      M    M
 24000  -38.5 -37.3   345   42   21   7.9   4.4   18.7  65.6    11.4      M    M
 23000  -36.1 -33.0   345   41   21   8.0   4.4   18.0  64.4    11.0      M    M
 22000  -33.8 -28.8   340   41   21   8.0   4.4   17.3  63.2    10.6      M    M
 21000  -31.4 -24.5   335   40   21   8.0   4.4   16.8  62.2    10.2      M    M
 20000  -29.0 -20.2   335   40   21   7.8   4.3   16.0  60.9     9.7      M    M
 19500  -27.9 -18.2   335   40   20   7.8   4.3   15.7  60.2     9.5      M    M
 19000  -26.7 -16.1   335   40   20   7.8   4.3   15.3  59.6     9.3      M    M
 18500  -25.5 -13.9   335   40   20   7.8   4.3   15.0  59.1     9.1      M    M
 18000  -24.4 -11.9   335   39   20   7.6   4.2   14.7  58.5     8.8      M    M
 17500  -23.3  -9.9   330   39   20   7.6   4.2   14.3  57.8     8.5      M    M
 17000  -22.1  -7.8   330   39   20   7.4   4.0   14.0  57.2     8.3      M    M
 16500  -21.0  -5.8   330   38   19   7.2   3.9   13.5  56.4     7.9      M    M
 16000  -19.4  -2.9   330   36   19   7.0   3.8   12.9  55.2     7.4      M    M
 15500  -18.4  -1.1   330   35   18   6.9   3.8   12.4  54.3     7.0      M    M
 15000  -17.4   0.7   330   34   18   6.2   3.4   11.9  53.5     6.6      M    M
 14500  -16.5   2.3   330   33   17   5.7   3.2   11.2  52.2     6.1      M    M
 14000  -15.6   3.9   330   31   16   5.5   3.0   10.6  51.1     5.5      M    M
 13500  -14.9   5.2   325   29   15   5.2   2.8    9.8  49.7     4.8      M    M
 13000  -14.1   6.6   325   27   14   5.1   2.8    9.1  48.4     4.2      M    M
 12500  -13.4   7.9   325   25   13   4.8   2.6    8.3  46.9     3.5      M    M
 12000  -12.6   9.3   325   22   11   4.6   2.5    7.5  45.5     2.8      M    M
 11500  -12.0  10.4   325   19   10   4.3   2.4    6.6  43.9     1.9      M    M
 11000  -11.4  11.5   320   16    8   5.0   2.7    5.7  42.3     1.1      M    M
 10500  -10.5  13.1   320   14    7   5.8   3.2    5.1  41.2     0.5      M    M
 10250  -10.1  13.8   315   13    7   5.8   3.2    4.8  40.6     0.2      M    M
 10000   -9.7  14.5   315   12    6   3.9   2.1    4.4  40.0    -0.1    347  1.8
  9750   -9.4  15.1   315   11    6   7.0   3.8    4.0  39.2    -0.5    330  1.7
  9500   -8.6  16.5   310   11    6  10.6   5.8    4.0  39.2    -0.5    301  1.5
  9250   -7.9  17.8   305   10    5   9.2   5.1    4.0  39.2    -0.5    272  1.4
  9000   -7.3  18.9   305   10    5   7.8   4.3    3.9  39.1    -0.6    245  1.2
  8750   -6.7  19.9   305   10    5   9.2   5.0    3.8  38.8    -0.8    220  1.1
  8500   -5.9  21.4   305   11    6  11.8   6.5    3.9  39.0    -0.7    188  1.0
  8250   -5.1  22.8   305   11    6   8.5   4.7    3.9  39.1    -0.6    157  0.8
  8000   -4.6  23.7   305   13    7   6.3   3.5    3.7  38.7    -0.9    135  0.7
  7750   -4.1  24.6   305   15    8   6.1   3.4    3.5  38.2    -1.1    112  0.6
  7500   -3.8  25.2   300   18    9   2.5   1.4    3.1  37.5    -1.5     96  0.5
  7250   -3.7  25.3   300   20   10  -1.0  -0.5    2.4  36.2    -2.2     87  0.4
  7000   -3.9  25.0   290   20   10  -1.9  -1.1    1.5  34.6    -3.1     84  0.4
  6750   -4.0  24.8   285   20   10  -1.7  -1.0    0.6  33.1    -4.0     81  0.4
  6500   -4.2  24.4   280   18    9  -2.1  -1.1   -0.3  31.5    -4.9     78  0.4
  6250   -4.4  24.1   275   16    8  -3.8  -2.1   -1.2  29.8    -5.8     76  0.4
  6000   -4.6  23.7   265   13    7   1.2   0.6   -2.2  28.1    -6.8     75  0.4
  5750   -5.0  23.0   250   11    6 -24.4 -13.4   -3.3  26.1    -7.9     79  0.4
  5500   -8.9  16.0   225    8    4 -75.5 -41.4   -7.9  17.7   -12.6    189  1.0

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

           03/05/2015 at 0800 MST          |       03/05/2015 at 1100 MST
                                           |
K index... -8.7  LI... +280.7              | K index... -7.6  LI... +279.7
CAPE... 0.0  CIN... -0.7                   | CAPE... 0.0  CIN... -0.7
                                           |
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 -56.2 -69.2  280  39 20   2.7   1.5 | -55.5 -67.9  290  37 19   2.2   1.2
 45000 -52.0 -61.6  280  38 19   2.8   1.5 | -52.1 -61.8  285  41 21   2.3   1.3
 40000 -51.3 -60.3  290  36 19   0.3   0.1 | -50.5 -58.9  290  37 19   1.0   0.5
 38000 -51.5 -60.7  295  36 18  -2.5  -1.4 | -50.6 -59.1  295  35 18  -4.2  -2.3
 36000 -53.0 -63.4  300  36 19  -2.4  -1.3 | -53.0 -63.4  305  36 19  -4.1  -2.2
 34000 -54.4 -65.9  310  38 19  -2.6  -1.4 | -55.7 -68.3  320  40 21  -3.0  -1.6
 32000 -53.8 -64.8  325  36 18   1.7   0.9 | -54.7 -66.5  330  42 22   2.2   1.2
 30000 -52.8 -63.0  335  36 18   4.1   2.3 | -53.3 -63.9  335  45 23   5.4   3.0
 29000 -50.6 -59.1  340  37 19   7.4   4.0 | -50.9 -59.6  335  43 22   8.1   4.4
 28000 -48.4 -55.1  345  39 20   7.4   4.0 | -48.5 -55.3  330  41 21   8.1   4.4
 27000 -46.2 -51.2  350  42 21   7.3   4.0 | -46.1 -51.0  330  39 20   8.0   4.4
 26000 -43.7 -46.7  350  42 22   8.8   4.8 | -43.3 -45.9  325  38 19   9.6   5.3
 25000 -41.1 -42.0  350  42 22   8.8   4.8 | -40.4 -40.7  325  36 19   9.6   5.3
 24000 -38.5 -37.3  345  41 21   8.8   4.8 | -37.6 -35.7  320  35 18   9.7   5.3
 23000 -35.8 -32.4  345  41 21   8.9   4.9 | -35.0 -31.0  320  35 18   8.2   4.5
 22000 -33.1 -27.6  345  41 21   9.0   4.9 | -32.5 -26.5  325  35 18   8.2   4.5
 21000 -30.4 -22.7  345  41 21   8.9   4.9 | -30.0 -22.0  330  36 19   8.2   4.5
 20000 -27.9 -18.2  340  39 20   8.4   4.6 | -27.6 -17.7  330  36 19   8.3   4.5
 19500 -26.6 -15.9  340  39 20   8.4   4.6 | -26.3 -15.3  330  36 19   8.3   4.5
 19000 -25.4 -13.7  340  38 20   8.4   4.6 | -25.1 -13.2  330  36 19   8.3   4.5
 18500 -24.1 -11.4  340  37 19   8.4   4.6 | -23.9 -11.0  330  36 19   8.3   4.5
 18000 -23.0  -9.4  340  36 19   7.1   3.9 | -22.6  -8.7  330  35 18   8.2   4.5
 17500 -21.9  -7.4  335  36 18   7.2   4.0 | -20.8  -5.4  330  34 17   8.4   4.6
 17000 -20.8  -5.4  335  35 18   7.6   4.2 | -19.4  -2.9  330  33 17   8.8   4.8
 16500 -19.1  -2.4  330  33 17   7.8   4.3 | -18.1  -0.6  330  31 16   8.9   4.9
 16000 -18.0  -0.4  330  32 16   6.7   3.7 | -16.8   1.8  330  30 15   8.0   4.4
 15500 -17.0   1.4  330  30 15   6.7   3.7 | -15.6   3.9  325  28 14   8.1   4.5
 15000 -16.0   3.2  325  28 15   6.2   3.4 | -14.5   5.9  325  26 13   7.0   3.8
 14500 -15.1   4.8  325  26 13   6.1   3.3 | -13.5   7.7  320  23 12   6.9   3.8
 14000 -14.2   6.4  320  23 12   5.4   2.9 | -12.5   9.5  315  20 11   5.8   3.2
 13500 -13.5   7.7  320  21 11   4.8   2.6 | -11.7  10.9  310  18  9   5.3   2.9
 13000 -12.8   9.0  315  19 10   4.5   2.5 | -10.9  12.4  300  16  8   4.3   2.4
 12500 -12.1  10.2  315  17  9   4.3   2.3 | -10.4  13.3  300  14  7   3.7   2.0
 12000 -11.5  11.3  315  14  7   4.6   2.5 |  -9.8  14.4  295  12  6   3.3   1.8
 11500 -10.8  12.6  315  12  6   5.1   2.8 |  -9.4  15.1  290  10  5   3.1   1.7
 11000 -10.0  14.0  310  10  5   5.2   2.8 |  -8.9  16.0  285   8  4   4.8   2.6
 10500  -9.2  15.4  310   8  4   5.4   2.9 |  -8.1  17.4  275   7  4   6.0   3.3
 10250  -8.8  16.2  310   7  4   4.8   2.6 |  -7.6  18.3  275   7  4   4.5   2.5
 10000  -8.5  16.7  305   6  3   3.9   2.2 |  -7.4  18.7  270   7  4   3.2   1.7
  9750  -8.1  17.4  305   6  3   7.6   4.1 |  -7.0  19.4  275   7  4   8.3   4.6
  9500  -7.4  18.7  305   6  3  10.7   5.9 |  -6.2  20.8  280   7  4  12.1   6.6
  9250  -6.7  19.9  300   6  3   8.9   4.9 |  -5.4  22.3  280   7  4   9.3   5.1
  9000  -6.1  21.0  305   6  3   6.8   3.7 |  -4.8  23.4  285   8  4   6.7   3.7
  8750  -5.6  21.9  315   7  4   8.7   4.8 |  -4.2  24.4  290   9  4   8.8   4.8
  8500  -4.8  23.4  325   8  4  11.0   6.0 |  -3.5  25.7  295  10  5  10.4   5.7
  8250  -4.1  24.6  325  10  5   7.3   4.0 |  -2.9  26.8  300  12  6   5.0   2.7
  8000  -3.7  25.3  325  13  7   5.0   2.7 |  -2.7  27.1  300  15  8   2.5   1.4
  7750  -3.3  26.1  320  16  8   5.7   3.1 |  -2.5  27.5  300  18  9   1.2   0.7
  7500  -3.0  26.6  315  19 10   1.7   0.9 |  -2.5  27.5  300  19 10   1.5   0.8
  7250  -3.1  26.4  310  20 10  -2.7  -1.5 |  -2.3  27.9  295  18  9   4.7   2.6
  7000  -3.3  26.1  305  19 10  -3.1  -1.7 |  -1.9  28.6  295  16  8   4.6   2.6
  6750  -3.5  25.7  295  19 10  -3.3  -1.8 |  -1.6  29.1  290  14  7   4.6   2.5
  6500  -3.8  25.2  290  17  9  -1.2  -0.7 |  -1.3  29.7  285  11  6   2.2   1.2
  6250  -3.7  25.3  285  14  7   1.9   1.0 |  -1.2  29.8  270   9  4   1.3   0.7
  6000  -3.6  25.5  280  11  6  -2.2  -1.2 |  -1.1  30.0  245   7  4  -0.0  -0.0
  5750  -4.5  23.9  260   8  4 -23.1 -12.7 |  -1.2  29.8  215   6  3  -0.2  -0.1
  5500  -7.2  19.0  230   6  3 -45.4 -24.9 |  -1.2  29.8  200   5  2   5.3   2.9

           03/05/2015 at 1400 MST          |       03/05/2015 at 1700 MST
                                           |
K index... -1.4  LI... +278.7              | K index... +2.6  LI... +277.5
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... -1.0
                                           |
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  280  36 19   2.5   1.4 | -55.6 -68.1  280  41 21   2.6   1.4
 45000 -51.5 -60.7  280  40 21   2.6   1.4 | -51.8 -61.2  280  43 22   2.7   1.5
 40000 -50.6 -59.1  285  34 17   0.4   0.2 | -54.2 -65.6  290  30 15  -1.9  -1.0
 38000 -51.0 -59.8  295  32 17  -2.7  -1.5 | -55.1 -67.2  305  28 14  -0.4  -0.2
 36000 -52.6 -62.7  315  36 19  -2.8  -1.5 | -55.3 -67.5  335  40 21  -0.4  -0.2
 34000 -54.3 -65.7  330  43 22  -3.1  -1.7 | -55.5 -67.9  345  58 30  -0.1  -0.0
 32000 -53.6 -64.5  340  51 26   1.7   0.9 | -54.1 -65.4  350  66 34   2.6   1.4
 30000 -52.6 -62.7  345  59 30   3.1   1.7 | -52.6 -62.7  355  73 37   5.4   3.0
 29000 -49.9 -57.8  340  55 28   7.9   4.4 | -49.2 -56.6  355  71 37   9.3   5.1
 28000 -47.5 -53.5  340  51 26   8.0   4.4 | -46.4 -51.5  355  70 36   9.3   5.1
 27000 -45.1 -49.2  335  48 25   7.9   4.3 | -43.6 -46.5  355  69 36   9.2   5.1
 26000 -42.7 -44.9  330  46 24   8.3   4.6 | -41.3 -42.3  355  65 33   7.4   4.0
 25000 -40.2 -40.4  330  45 23   8.3   4.6 | -39.1 -38.4  350  60 31   7.4   4.1
 24000 -37.7 -35.9  330  43 22   8.3   4.5 | -36.9 -34.4  350  55 28   7.3   4.0
 23000 -35.1 -31.2  330  41 21   8.9   4.9 | -34.5 -30.1  345  51 26   8.3   4.6
 22000 -32.4 -26.3  325  39 20   8.9   4.9 | -32.0 -25.6  340  48 25   8.3   4.6
 21000 -29.7 -21.5  325  38 19   8.5   4.7 | -29.6 -21.3  335  45 23   8.3   4.5
 20000 -27.4 -17.3  320  36 18   8.0   4.4 | -27.1 -16.8  330  42 22   8.2   4.5
 19500 -26.2 -15.2  320  35 18   8.0   4.4 | -25.9 -14.6  330  41 21   8.2   4.5
 19000 -25.0 -13.0  315  34 18   8.0   4.4 | -24.7 -12.5  325  39 20   8.2   4.5
 18500 -23.8 -10.8  315  33 17   8.0   4.4 | -23.5 -10.3  325  38 20   8.3   4.5
 18000 -22.6  -8.7  315  33 17   8.0   4.4 | -22.2  -8.0  320  36 19   8.3   4.6
 17500 -21.4  -6.5  310  32 16   7.9   4.3 | -21.0  -5.8  320  34 17   8.3   4.6
 17000 -20.2  -4.4  310  31 16   9.1   5.0 | -19.8  -3.6  320  32 17   8.0   4.4
 16500 -18.8  -1.8  310  29 15   9.0   5.0 | -18.5  -1.3  320  32 16   8.1   4.4
 16000 -17.5   0.5  310  28 14   8.5   4.7 | -17.4   0.7  320  31 16   7.0   3.8
 15500 -15.6   3.9  305  25 13   8.5   4.7 | -16.4   2.5  325  31 16   6.7   3.7
 15000 -14.5   5.9  305  24 12   6.2   3.4 | -14.9   5.2  325  30 16   6.1   3.3
 14500 -13.5   7.7  310  23 12   6.3   3.5 | -14.0   6.8  325  28 14   6.1   3.4
 14000 -12.7   9.1  310  21 11   4.9   2.7 | -13.1   8.4  325  26 14   6.3   3.4
 13500 -12.0  10.4  315  20 10   4.6   2.5 | -12.2  10.0  330  25 13   6.2   3.4
 13000 -11.3  11.7  315  19 10   4.0   2.2 | -11.2  11.8  335  24 12   6.7   3.7
 12500 -10.8  12.6  320  18  9   3.7   2.0 | -10.2  13.6  335  22 11   6.7   3.7
 12000 -10.2  13.6  320  17  9   5.1   2.8 |  -9.2  15.4  335  20 10   7.8   4.3
 11500  -9.4  15.1  320  16  8   5.6   3.1 |  -8.0  17.6  335  19 10   8.0   4.4
 11000  -8.4  16.9  320  15  8   8.1   4.5 |  -6.8  19.8  330  19 10   7.7   4.2
 10500  -7.1  19.2  320  15  8   9.3   5.1 |  -5.7  21.7  325  21 11   8.1   4.5
 10250  -6.4  20.5  320  16  8   6.8   3.8 |  -5.2  22.6  320  22 11   5.6   3.1
 10000  -6.1  21.0  320  16  8   5.7   3.1 |  -4.9  23.2  320  22 12   3.4   1.9
  9750  -5.5  22.1  315  17  9   9.6   5.3 |  -4.6  23.7  315  24 12   5.3   2.9
  9500  -4.7  23.5  315  19 10  12.5   6.8 |  -4.2  24.4  310  26 13   6.0   3.3
  9250  -3.8  25.2  315  20 11   7.1   3.9 |  -3.8  25.2  305  28 14   5.0   2.7
  9000  -3.6  25.5  310  22 11   1.9   1.1 |  -3.4  25.9  305  27 14   4.2   2.3
  8750  -3.4  25.9  310  24 12   4.4   2.4 |  -3.1  26.4  300  27 14   6.3   3.5
  8500  -3.1  26.4  305  24 12   5.1   2.8 |  -2.6  27.3  300  25 13   7.3   4.0
  8250  -2.7  27.1  305  24 12   5.1   2.8 |  -2.1  28.2  300  23 12   6.2   3.4
  8000  -2.3  27.9  300  22 11   5.2   2.9 |  -1.7  28.9  305  21 11   5.9   3.3
  7750  -2.0  28.4  300  20 10   5.3   2.9 |  -1.2  29.8  305  19 10   6.0   3.3
  7500  -1.6  29.1  305  18  9   3.8   2.1 |  -0.8  30.6  305  18  9   4.0   2.2
  7250  -1.4  29.5  305  15  8   2.6   1.4 |  -0.6  30.9  305  15  8   2.5   1.4
  7000  -1.2  29.8  305  12  6   2.5   1.4 |  -0.4  31.3  300  12  6   3.0   1.6
  6750  -1.0  30.2  305   9  5   3.5   1.9 |  -0.2  31.6  300  10  5   2.6   1.4
  6500  -0.7  30.7  305   7  3   4.5   2.5 |  -0.0  32.0  295   7  4   3.2   1.8
  6250  -0.3  31.5  295   4  2   4.4   2.4 |   0.3  32.5  285   5  3   3.8   2.1
  6000  -0.0  32.0  265   3  1   4.0   2.2 |   0.6  33.1  265   4  2   4.2   2.3
  5750   0.2  32.4  210   2  1   4.7   2.6 |   0.8  33.4  235   3  1   1.6   0.9
  5500   0.5  32.9  170   1  1   7.7   4.2 |   0.5  32.9  200   1  1  -4.3  -2.3
________________________________________________________________________________

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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