Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 050109
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1809 MST Wednesday, March 4, 2015

This forecast is for Thursday, March 5, 2015:

If the trigger temperature of 36.6 F/2.5 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 371 ft/min (1.9 m/s)
   Maximum height of thermals.................. 10530 ft MSL (5223 ft AGL)

Forecast maximum temperature................... 40.0 F/4.9 C
Time of trigger temperature.................... 1230 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7377 ft MSL (2071 ft AGL)
Thermal soaring outlook for Friday 03/06....... Good

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1700 MST)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 26691 ft MSL (21384 ft AGL)
Wave soaring outlook for Friday 03/06.......... Fair

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... 19535 ft MSL (14228 ft AGL)
Lifted condensation level....... 15526 ft MSL (10219 ft AGL)
Lifted index.................... +10.6
K index......................... -17.1

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -56.6 -69.9   280   44   23   2.6   1.4      M     M       M      M    M
 45000  -52.5 -62.5   280   43   22   2.7   1.5      M     M       M      M    M
 40000  -51.5 -60.7   280   35   18   0.5   0.3      M     M       M      M    M
 38000  -51.6 -60.9   285   33   17  -3.2  -1.8      M     M       M      M    M
 36000  -53.5 -64.3   290   32   17  -3.1  -1.7      M     M       M      M    M
 34000  -55.3 -67.5   290   32   17  -3.4  -1.9      M     M       M      M    M
 32000  -53.8 -64.8   305   30   15   3.8   2.1      M     M       M      M    M
 30000  -51.3 -60.3   320   29   15   5.5   3.0      M     M       M      M    M
 29000  -49.0 -56.2   330   30   16   7.5   4.1   23.8  74.9    14.6      M    M
 28000  -46.8 -52.2   335   32   17   7.5   4.1   22.9  73.3    14.1      M    M
 27000  -44.5 -48.1   340   34   18   7.5   4.1   22.2  71.9    13.7      M    M
 26000  -42.2 -44.0   340   35   18   7.8   4.3   21.4  70.4    13.3      M    M
 25000  -39.9 -39.8   340   35   18   7.8   4.3   20.5  69.0    12.8      M    M
 24000  -37.6 -35.7   340   35   18   7.8   4.3   19.9  67.8    12.4      M    M
 23000  -35.4 -31.7   335   34   18   7.1   3.9   19.0  66.2    11.8      M    M
 22000  -33.2 -27.8   335   34   17   7.1   3.9   18.0  64.4    11.1      M    M
 21000  -31.1 -24.0   330   33   17   7.1   3.9   17.1  62.8    10.5      M    M
 20000  -28.9 -20.0   330   34   18   7.5   4.1   16.2  61.2     9.9      M    M
 19500  -27.8 -18.0   330   35   18   7.5   4.1   15.8  60.5     9.6      M    M
 19000  -26.7 -16.1   330   35   18   7.5   4.1   15.4  59.8     9.4      M    M
 18500  -25.5 -13.9   330   36   18   7.5   4.1   15.1  59.2     9.1      M    M
 18000  -24.4 -11.9   330   36   18   7.6   4.2   14.7  58.5     8.8      M    M
 17500  -23.3  -9.9   330   36   18   7.6   4.2   14.3  57.8     8.6      M    M
 17000  -22.1  -7.8   330   36   18   7.6   4.1   14.0  57.2     8.3      M    M
 16500  -21.0  -5.8   325   35   18   7.5   4.1   13.6  56.5     8.0      M    M
 16000  -19.9  -3.8   325   35   18   7.4   4.0   13.2  55.8     7.7      M    M
 15500  -18.3  -0.9   325   33   17   6.9   3.8   12.5  54.5     7.1      M    M
 15000  -17.3   0.9   325   33   17   6.3   3.4   12.0  53.7     6.7      M    M
 14500  -16.4   2.5   325   32   16   5.9   3.3   11.4  52.5     6.2      M    M
 14000  -15.5   4.1   325   31   16   5.3   2.9   10.8  51.4     5.7      M    M
 13500  -14.8   5.4   325   29   15   4.7   2.6    9.9  49.9     4.9      M    M
 13000  -14.1   6.6   325   28   14   4.3   2.4    9.1  48.4     4.2      M    M
 12500  -13.5   7.7   325   26   13   3.9   2.2    8.1  46.7     3.4      M    M
 12000  -12.9   8.8   320   24   12   3.8   2.1    7.2  45.0     2.5      M    M
 11500  -12.4   9.7   320   21   11   3.7   2.0    6.2  43.2     1.6      M    M
 11000  -11.8  10.8   320   18    9   4.1   2.2    5.3  41.5     0.7      M    M
 10500  -11.2  11.8   320   15    8   4.5   2.5    4.4  39.9    -0.1    366  1.9
 10250  -10.9  12.4   320   14    7   4.2   2.3    4.0  39.2    -0.5    349  1.8
 10000  -10.6  12.9   315   12    6   2.1   1.1    3.5  38.3    -1.0    334  1.7
  9750  -10.4  13.3   315   12    6   5.0   2.8    2.9  37.3    -1.5    321  1.6
  9500   -9.9  14.2   305   10    5   8.5   4.7    2.8  37.0    -1.7    297  1.5
  9250   -9.3  15.3   300    9    4   7.1   3.9    2.6  36.7    -1.9    273  1.4
  9000   -8.8  16.2   290    8    4   5.8   3.2    2.4  36.2    -2.1    250  1.3
  8750   -8.3  17.1   285    8    4   8.1   4.5    2.1  35.7    -2.4    229  1.2
  8500   -7.6  18.3   285    8    4  10.8   5.9    2.1  35.8    -2.4    199  1.0
  8250   -6.8  19.8   285    8    4   9.1   5.0    2.1  35.8    -2.4    170  0.9
  8000   -6.2  20.8   285    9    5   8.0   4.4    2.0  35.6    -2.5    143  0.7
  7750   -5.6  21.9   290   10    5   9.6   5.3    1.9  35.5    -2.6    117  0.6
  7500   -4.9  23.2   295   11    6   5.8   3.2    1.9  35.4    -2.6     90  0.5
  7250   -4.8  23.4   290   13    6  -0.0  -0.0    1.3  34.3    -3.3     78  0.4
  7000   -4.8  23.4   285   14    7   0.4   0.2    0.5  32.9    -4.0     71  0.4
  6750   -4.8  23.4   285   15    8  -0.7  -0.4   -0.2  31.6    -4.7     64  0.3
  6500   -4.9  23.2   280   15    8  -1.0  -0.6   -1.0  30.1    -5.6     59  0.3
  6250   -4.9  23.2   270   13    7   1.7   0.9   -1.8  28.8    -6.3     52  0.3
  6000   -4.9  23.2   260   12    6  -4.2  -2.3   -2.5  27.5    -7.1     44  0.2
  5750   -6.0  21.2   245   11    6 -30.5 -16.7   -4.4  24.1    -9.0     72  0.4
  5500   -9.4  15.1   225    9    5 -56.3 -30.9   -8.5  16.7   -13.1    166  0.8

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

           03/05/2015 at 0800 MST          |       03/05/2015 at 1100 MST
                                           |
K index... -12.7  LI... +281.8             | K index... -16.1  LI... +280.1
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 -56.5 -69.7  280  38 19   2.5   1.3 | -55.5 -67.9  280  31 16   2.1   1.1
 45000 -52.6 -62.7  275  36 19   2.6   1.4 | -52.4 -62.3  280  37 19   2.2   1.2
 40000 -51.4 -60.5  285  33 17   0.7   0.4 | -51.7 -61.1  285  35 18   0.3   0.2
 38000 -51.5 -60.7  290  32 16  -3.0  -1.7 | -51.9 -61.4  285  34 18  -3.1  -1.7
 36000 -53.3 -63.9  300  34 17  -3.0  -1.6 | -53.7 -64.7  300  33 17  -3.0  -1.7
 34000 -55.1 -67.2  305  36 19  -3.3  -1.8 | -55.8 -68.4  315  35 18  -1.7  -1.0
 32000 -54.0 -65.2  320  36 18   2.5   1.4 | -54.6 -66.3  320  38 20   2.2   1.2
 30000 -52.5 -62.5  330  37 19   5.5   3.0 | -53.2 -63.8  325  43 22   6.2   3.4
 29000 -50.1 -58.2  335  37 19   8.0   4.4 | -50.6 -59.1  325  43 22   8.9   4.9
 28000 -47.7 -53.9  340  38 20   8.0   4.4 | -47.9 -54.2  325  43 22   8.9   4.9
 27000 -45.3 -49.5  345  39 20   8.0   4.4 | -45.3 -49.5  325  43 22   8.9   4.9
 26000 -42.7 -44.9  345  39 20   8.7   4.8 | -42.6 -44.7  325  41 21   8.6   4.7
 25000 -40.1 -40.2  340  37 19   8.8   4.8 | -40.1 -40.2  330  39 20   8.6   4.7
 24000 -37.5 -35.5  340  36 18   8.8   4.8 | -37.5 -35.5  335  37 19   8.7   4.7
 23000 -34.9 -30.8  340  36 18   8.4   4.6 | -34.9 -30.8  335  35 18   8.5   4.7
 22000 -32.4 -26.3  340  37 19   8.4   4.6 | -32.3 -26.1  340  34 17   8.5   4.7
 21000 -29.9 -21.8  340  38 20   8.4   4.6 | -29.8 -21.6  340  32 17   8.4   4.6
 20000 -27.4 -17.3  340  37 19   8.0   4.4 | -27.4 -17.3  340  32 16   7.8   4.3
 19500 -26.3 -15.3  340  37 19   8.0   4.4 | -26.2 -15.2  340  32 16   7.8   4.3
 19000 -25.1 -13.2  340  36 19   8.0   4.4 | -25.1 -13.2  335  32 16   7.9   4.3
 18500 -23.9 -11.0  340  36 18   7.9   4.4 | -23.9 -11.0  335  32 16   7.9   4.4
 18000 -22.8  -9.0  340  35 18   6.9   3.8 | -22.6  -8.7  335  31 16   8.4   4.6
 17500 -21.7  -7.1  340  34 18   7.0   3.8 | -20.8  -5.4  335  31 16   8.2   4.5
 17000 -20.7  -5.3  335  33 17   6.6   3.6 | -19.6  -3.3  335  30 16   7.7   4.2
 16500 -19.3  -2.7  335  32 17   6.4   3.5 | -18.4  -1.1  335  30 15   7.8   4.3
 16000 -18.3  -0.9  330  31 16   6.6   3.6 | -17.3   0.9  335  29 15   7.1   3.9
 15500 -17.3   0.9  330  29 15   6.7   3.7 | -16.2   2.8  335  29 15   7.2   4.0
 15000 -16.3   2.7  325  27 14   5.9   3.2 | -15.2   4.6  335  29 15   6.7   3.7
 14500 -15.5   4.1  325  25 13   5.7   3.1 | -14.2   6.4  330  27 14   6.7   3.7
 14000 -14.7   5.5  325  23 12   5.2   2.9 | -13.2   8.2  330  25 13   5.6   3.1
 13500 -13.9   7.0  320  21 11   4.9   2.7 | -12.4   9.7  330  23 12   5.2   2.9
 13000 -13.2   8.2  320  19 10   4.7   2.6 | -11.7  10.9  330  20 10   5.0   2.7
 12500 -12.5   9.5  315  17  9   4.6   2.5 | -11.0  12.2  330  18  9   4.9   2.7
 12000 -11.8  10.8  310  16  8   4.0   2.2 | -10.2  13.6  330  16  8   5.0   2.8
 11500 -11.3  11.7  305  14  7   3.4   1.9 |  -9.5  14.9  325  14  7   5.2   2.8
 11000 -10.8  12.6  300  12  6   4.6   2.5 |  -8.7  16.3  320  12  6   3.9   2.1
 10500 -10.0  14.0  290  10  5   5.5   3.0 |  -8.2  17.2  315  10  5   3.5   1.9
 10250  -9.6  14.7  285  10  5   4.8   2.7 |  -8.0  17.6  310   9  5   2.8   1.5
 10000  -9.3  15.3  280  10  5   3.2   1.7 |  -7.8  18.0  305   8  4   2.5   1.4
  9750  -9.0  15.8  280   9  5   7.1   3.9 |  -7.5  18.5  305   8  4   6.3   3.5
  9500  -8.2  17.2  275   9  5  11.1   6.1 |  -6.9  19.6  300   8  4   9.0   4.9
  9250  -7.5  18.5  275   9  5   8.3   4.6 |  -6.3  20.7  290   7  4   7.1   3.9
  9000  -7.0  19.4  275   9  5   5.5   3.0 |  -5.9  21.4  295   7  4   4.8   2.6
  8750  -6.6  20.1  280  10  5   7.6   4.2 |  -5.4  22.3  295   7  4   8.8   4.8
  8500  -5.9  21.4  285  11  5   9.4   5.1 |  -4.6  23.7  300   7  4  11.3   6.2
  8250  -5.3  22.5  285  12  6   6.4   3.5 |  -3.9  25.0  305   8  4   6.8   3.7
  8000  -4.9  23.2  290  13  7   4.8   2.6 |  -3.5  25.7  305  10  5   5.5   3.0
  7750  -4.5  23.9  290  14  7   6.0   3.3 |  -3.1  26.4  300  12  6   5.2   2.8
  7500  -4.1  24.6  295  16  8   3.8   2.1 |  -2.8  27.0  300  15  8   2.7   1.5
  7250  -3.9  25.0  290  15  8   1.0   0.5 |  -2.7  27.1  295  14  7   1.7   1.0
  7000  -3.9  25.0  285  15  8   1.4   0.7 |  -2.6  27.3  285  12  6   1.6   0.9
  6750  -3.8  25.2  285  15  8   0.8   0.5 |  -2.4  27.7  275  11  6   2.7   1.5
  6500  -3.8  25.2  280  14  7  -1.3  -0.7 |  -2.2  28.0  260   9  5   3.8   2.1
  6250  -3.9  25.0  275  12  6  -0.4  -0.2 |  -1.9  28.6  245   8  4   4.6   2.5
  6000  -4.0  24.8  270  10  5  -6.0  -3.3 |  -1.6  29.1  230   7  4   1.0   0.6
  5750  -5.2  22.6  250   9  5 -26.9 -14.8 |  -1.8  28.8  215   7  3  -1.8  -1.0
  5500  -8.0  17.6  230   7  4 -42.8 -23.5 |  -1.8  28.8  200   6  3   4.8   2.6

           03/05/2015 at 1400 MST          |       03/05/2015 at 1700 MST
                                           |
K index... -14.3  LI... +279.4             | K index... -5.0  LI... +279.2
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 -55.6 -68.1  275  30 15   2.4   1.3 | -55.9 -68.6  280  33 17   2.2   1.2
 45000 -52.0 -61.6  275  36 19   2.5   1.4 | -52.7 -62.9  275  36 18   2.3   1.3
 40000 -51.4 -60.5  285  33 17   0.3   0.1 | -53.4 -64.1  300  29 15  -0.6  -0.4
 38000 -51.6 -60.9  295  32 16  -3.0  -1.6 | -53.9 -65.0  310  29 15  -1.1  -0.6
 36000 -53.6 -64.5  310  32 17  -2.9  -1.6 | -54.5 -66.1  330  31 16  -1.1  -0.6
 34000 -55.4 -67.7  325  34 18  -1.5  -0.8 | -55.2 -67.4  340  35 18  -0.4  -0.2
 32000 -54.4 -65.9  330  36 18   1.9   1.0 | -53.8 -64.8  355  42 22   2.5   1.4
 30000 -53.1 -63.6  330  37 19   6.1   3.4 | -52.4 -62.3  005  52 27   4.8   2.7
 29000 -50.6 -59.1  330  35 18   8.5   4.7 | -50.1 -58.2  005  51 26   7.6   4.2
 28000 -48.0 -54.4  325  34 17   8.5   4.7 | -47.3 -53.1  005  49 25   7.6   4.2
 27000 -45.5 -49.9  325  32 17   8.4   4.6 | -45.0 -49.0  005  47 24   7.8   4.3
 26000 -42.7 -44.9  325  33 17   9.2   5.1 | -42.3 -44.1  005  45 23   9.4   5.1
 25000 -40.0 -40.0  330  36 18   9.3   5.1 | -39.5 -39.1  360  44 22   9.3   5.1
 24000 -37.2 -35.0  330  38 20   9.3   5.1 | -36.7 -34.1  360  42 21   9.3   5.1
 23000 -34.6 -30.3  330  37 19   8.2   4.5 | -34.0 -29.2  360  39 20   8.9   4.9
 22000 -32.2 -26.0  335  35 18   8.2   4.5 | -31.3 -24.3  360  35 18   8.9   4.9
 21000 -29.7 -21.5  335  32 17   8.2   4.5 | -28.7 -19.7  355  32 17   8.7   4.8
 20000 -27.3 -17.1  330  31 16   8.0   4.4 | -26.1 -15.0  350  31 16   8.6   4.7
 19500 -26.1 -15.0  330  30 16   8.0   4.4 | -24.8 -12.6  345  30 16   8.7   4.7
 19000 -24.9 -12.8  330  30 15   8.0   4.4 | -23.5 -10.3  340  30 15   8.6   4.7
 18500 -23.1  -9.6  325  29 15   8.0   4.4 | -22.2  -8.0  335  30 15   8.1   4.5
 18000 -21.9  -7.4  325  28 15   8.0   4.4 | -21.1  -6.0  335  30 15   7.6   4.2
 17500 -20.7  -5.3  325  28 14   7.9   4.4 | -20.0  -4.0  330  30 16   7.6   4.2
 17000 -19.5  -3.1  325  28 14   7.7   4.2 | -18.9  -2.0  330  30 16   7.2   4.0
 16500 -18.3  -0.9  325  27 14   7.8   4.3 | -17.8  -0.0  325  30 16   7.2   4.0
 16000 -17.2   1.0  325  27 14   7.2   3.9 | -16.7   1.9  325  30 15   7.4   4.1
 15500 -16.1   3.0  325  27 14   7.3   4.0 | -15.6   3.9  325  29 15   7.4   4.1
 15000 -15.0   5.0  325  26 14   6.7   3.7 | -14.0   6.8  320  28 14   7.1   3.9
 14500 -14.0   6.8  325  25 13   6.7   3.7 | -12.9   8.8  320  27 14   7.2   3.9
 14000 -13.1   8.4  325  24 12   6.1   3.4 | -11.9  10.6  320  25 13   6.2   3.4
 13500 -12.2  10.0  325  22 11   6.0   3.3 | -11.0  12.2  315  23 12   6.1   3.4
 13000 -11.3  11.7  325  20 10   5.9   3.3 | -10.1  13.8  315  21 11   6.1   3.3
 12500 -10.4  13.3  325  18  9   5.9   3.3 |  -9.2  15.4  315  19 10   6.1   3.3
 12000  -9.5  14.9  330  17  9   5.9   3.3 |  -8.3  17.1  315  18  9   5.4   2.9
 11500  -8.6  16.5  325  15  7   6.0   3.3 |  -7.6  18.3  310  16  8   5.1   2.8
 11000  -7.8  18.0  325  13  6   5.3   2.9 |  -6.7  19.9  305  14  7   6.4   3.5
 10500  -7.0  19.4  320  11  5   5.5   3.0 |  -5.8  21.6  305  13  7   7.1   3.9
 10250  -6.6  20.1  320  10  5   3.6   2.0 |  -5.3  22.5  305  13  7   4.7   2.6
 10000  -6.5  20.3  315   9  5   2.2   1.2 |  -5.0  23.0  305  13  6   5.5   3.0
  9750  -6.2  20.8  310   9  5   5.8   3.2 |  -4.4  24.1  305  13  7  10.6   5.8
  9500  -5.6  21.9  305   9  4   7.9   4.3 |  -3.5  25.7  305  14  7  12.2   6.7
  9250  -5.1  22.8  300   9  4   6.5   3.6 |  -2.7  27.1  305  15  8   8.3   4.5
  9000  -4.7  23.5  300   9  5   5.2   2.9 |  -2.3  27.9  300  16  8   4.8   2.6
  8750  -4.2  24.4  300   9  5   9.2   5.0 |  -1.9  28.6  300  18  9   6.2   3.4
  8500  -3.4  25.9  300   9  5  11.2   6.1 |  -1.5  29.3  300  19 10   5.7   3.1
  8250  -2.7  27.1  305  10  5   7.4   4.1 |  -1.1  30.0  300  20 10   4.4   2.4
  8000  -2.2  28.0  305  11  6   6.2   3.4 |  -0.9  30.4  295  19 10   3.6   2.0
  7750  -1.8  28.8  305  13  6   7.0   3.9 |  -0.6  30.9  295  18  9   4.6   2.5
  7500  -1.3  29.7  310  14  7   4.7   2.6 |  -0.2  31.6  295  16  8   4.2   2.3
  7250  -1.1  30.0  305  12  6   2.6   1.4 |   0.0  32.0  290  14  7   3.0   1.7
  7000  -0.9  30.4  305  10  5   3.0   1.6 |   0.2  32.4  290  12  6   3.3   1.8
  6750  -0.7  30.7  300   8  4   3.1   1.7 |   0.5  32.9  285   9  5   3.2   1.7
  6500  -0.4  31.3  290   6  3   3.0   1.6 |   0.7  33.3  275   8  4   3.2   1.8
  6250  -0.2  31.6  260   4  2   2.5   1.4 |   1.0  33.8  255   7  3   3.2   1.8
  6000   0.0  32.0  220   4  2   2.7   1.5 |   1.2  34.2  235   7  3   3.2   1.8
  5750   0.2  32.4  195   4  2   4.3   2.4 |   1.3  34.3  220   6  3  -1.4  -0.8
  5500   0.4  32.7  180   3  2   7.2   3.9 |   0.8  33.4  205   4  2  -8.9  -4.9
________________________________________________________________________________

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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