Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 260027
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1727 MST Wednesday, February 25, 2015

This forecast is for Thursday, February 26, 2015:

If the trigger temperature of 26.2 F/-3.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5307 ft MSL (0 ft AGL)

Forecast maximum temperature................... 19.0 F/-7.7 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................. None
Thermal soaring outlook for Friday 02/27....... Poor

Wave Soaring Index............................. Fair
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....................... 14896 ft MSL (9589 ft AGL)
Wave soaring outlook for Friday 02/27.......... Poor

Remarks... Snow will continue tonight and Thursday

Sunrise/Sunset.................... 06:37:07 / 17:46:51 MST
Total possible sunshine........... 11 hr 9 min 44 sec (669 min 44 sec)
Altitude of sun at 12:12:15 MST... 41.64 degrees

Upper air data from numerical model forecast valid on 02/26/2015 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 8076 ft MSL (2769 ft AGL)
Lifted condensation level....... 7264 ft MSL (1957 ft AGL)
Lifted index.................... +14.5
K index......................... +4.1

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  -53.1 -63.6   310   42   21   2.6   1.4      M     M       M      M    M
 45000  -49.0 -56.2   310   51   26   2.6   1.5      M     M       M      M    M
 40000  -48.8 -55.8   315   59   30  -0.4  -0.2      M     M       M      M    M
 38000  -49.1 -56.4   315   62   32  -1.2  -0.6      M     M       M      M    M
 36000  -50.9 -59.6   315   61   32  -3.2  -1.8      M     M       M      M    M
 34000  -52.9 -63.2   315   60   31  -3.2  -1.8      M     M       M      M    M
 32000  -53.1 -63.6   320   64   33   1.9   1.0      M     M       M      M    M
 30000  -51.9 -61.4   325   71   37   2.0   1.1      M     M       M      M    M
 29000  -50.6 -59.1   325   73   38   7.5   4.1   23.5  74.3    23.0      M    M
 28000  -48.4 -55.1   325   73   37   7.4   4.0   22.5  72.4    22.6      M    M
 27000  -46.2 -51.2   330   72   37   7.4   4.0   21.6  70.8    22.2      M    M
 26000  -44.0 -47.2   330   72   37   5.7   3.1   20.8  69.4    21.8      M    M
 25000  -42.7 -44.9   325   63   33   4.5   2.4   18.6  65.5    20.4      M    M
 24000  -41.3 -42.3   325   55   28   4.4   2.4   16.6  61.9    19.0      M    M
 23000  -40.0 -40.0   320   47   24   5.1   2.8   14.8  58.6    17.8      M    M
 22000  -38.3 -36.9   320   44   22   5.7   3.1   13.1  55.6    16.7      M    M
 21000  -36.6 -33.9   315   40   21   5.7   3.1   11.7  53.0    15.7      M    M
 20000  -35.0 -31.0   315   36   19   4.9   2.7   10.2  50.3    14.6      M    M
 19500  -34.3 -29.7   310   34   17   4.9   2.7    9.3  48.7    13.9      M    M
 19000  -33.5 -28.3   310   31   16   4.9   2.7    8.4  47.1    13.3      M    M
 18500  -32.8 -27.0   305   29   15   5.0   2.7    7.6  45.6    12.6      M    M
 18000  -32.1 -25.8   305   27   14   5.2   2.9    6.8  44.2    12.0      M    M
 17500  -31.1 -24.0   300   26   13   7.1   3.9    6.2  43.2    11.6      M    M
 17000  -30.1 -22.2   300   25   13   6.9   3.8    5.7  42.3    11.3      M    M
 16500  -28.9 -20.0   300   24   12   8.4   4.6    5.4  41.7    11.0      M    M
 16000  -27.1 -16.8   295   25   13   8.5   4.6    5.0  41.1    10.8      M    M
 15500  -25.7 -14.3   295   26   13   9.4   5.1    4.9  40.8    10.7      M    M
 15000  -24.3 -11.7   295   27   14   9.3   5.1    4.8  40.7    10.7      M    M
 14500  -22.9  -9.2   295   27   14   9.3   5.1    4.7  40.5    10.7      M    M
 14000  -21.6  -6.9   290   27   14   9.4   5.2    4.7  40.4    10.7      M    M
 13500  -20.3  -4.5   290   27   14   8.3   4.6    4.5  40.1    10.6      M    M
 13000  -19.0  -2.2   290   26   13   8.7   4.8    4.3  39.7    10.4      M    M
 12500  -18.0  -0.4   285   24   13   4.6   2.5    3.8  38.9    10.0      M    M
 12000  -17.3   0.9   280   23   12   4.9   2.7    3.0  37.4     9.3      M    M
 11500  -16.8   1.8   275   20   11   2.8   1.5    2.0  35.7     8.4      M    M
 11000  -16.3   2.7   270   18    9   2.9   1.6    1.7  33.7     7.5      M    M
 10500  -16.0   3.2   265   16    8   2.3   1.3   -0.2  31.7     6.4      M    M
 10250  -15.8   3.6   265   15    8   2.9   1.6   -0.8  30.6     5.9      M    M
 10000  -15.6   3.9   265   14    7   0.9   0.5   -1.3  29.6     5.4      M    M
  9750  -15.6   3.9   260   13    7   1.4   0.8   -2.1  28.3     4.7      M    M
  9500  -15.3   4.5   265   11    5   3.9   2.1   -2.6  27.3     4.2      M    M
  9250  -15.1   4.8   275    8    4   3.5   1.9   -3.1  26.4     3.7      M    M
  9000  -14.8   5.4   295    5    3   3.0   1.7   -3.6  25.6     3.2      M    M
  8750  -14.6   5.7   330    4    2   3.9   2.1   -4.1  24.6     2.8      M    M
  8500  -14.2   6.4   360    4    2   5.4   3.0   -4.5  23.9     2.4      M    M
  8250  -13.8   7.2   020    5    3   6.2   3.4   -4.8  23.4     2.1      M    M
  8000  -13.3   8.1   035    6    3   8.4   4.6   -5.0  23.0     1.9      M    M
  7750  -12.6   9.3   045    5    2   8.9   4.9   -5.0  22.9     1.8      M    M
  7500  -12.0  10.4   055    4    2   8.3   4.5   -5.1  22.7     1.7      M    M
  7250  -11.4  11.5   065    4    2   8.3   4.5   -5.3  22.5     1.6      M    M
  7000  -10.8  12.6   075    5    2   8.1   4.4   -5.4  22.3     1.5      M    M
  6750  -10.2  13.6   080    5    3   8.7   4.8   -5.5  22.1     1.4      M    M
  6500   -9.5  14.9   080    6    3   9.4   5.1   -5.5  22.0     1.3      M    M
  6250   -8.8  16.2   080    6    3   9.1   5.0   -5.6  22.0     1.3      M    M
  6000   -8.2  17.2   075    6    3   9.4   5.2   -5.6  21.9     1.2      M    M
  5750   -7.5  18.5   075    5    3   8.3   4.5   -5.7  21.8     1.2      M    M
  5500   -7.0  19.4   070    5    2   5.8   3.2   -5.9  21.4     0.9      M    M

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

           02/26/2015 at 0800 MST          |       02/26/2015 at 1100 MST
                                           |
K index... +3.4  LI... +276.6              | K index... +2.0  LI... +277.6
CAPE... 0.0  CIN... -0.1                   | 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 -52.4 -62.3  310  45 23   1.8   1.0 | -52.3 -62.1  305  42 22   2.0   1.1
 45000 -49.8 -57.6  310  49 25   1.8   1.0 | -49.3 -56.7  300  46 24   2.0   1.1
 40000 -49.5 -57.1  310  54 28  -0.2  -0.1 | -48.8 -55.8  305  48 25  -0.0  -0.0
 38000 -49.5 -57.1  315  57 29  -1.4  -0.7 | -48.8 -55.8  305  49 25  -1.3  -0.7
 36000 -52.2 -62.0  315  59 31  -4.6  -2.5 | -51.9 -61.4  305  52 27  -5.5  -3.0
 34000 -55.0 -67.0  315  62 32  -4.6  -2.6 | -55.3 -67.5  305  56 29  -5.5  -3.0
 32000 -55.2 -67.4  315  67 34   3.2   1.8 | -55.7 -68.3  305  58 30   3.3   1.8
 30000 -53.0 -63.4  315  74 38   3.4   1.9 | -53.5 -64.3  305  60 31   3.4   1.9
 29000 -51.3 -60.3  315  75 39   8.2   4.5 | -51.9 -61.4  305  61 31   8.1   4.4
 28000 -48.8 -55.8  315  74 38   8.3   4.5 | -49.4 -56.9  305  62 32   8.2   4.5
 27000 -46.4 -51.5  315  73 38   8.3   4.5 | -46.9 -52.4  305  62 32   8.2   4.5
 26000 -43.9 -47.0  320  72 37   7.2   4.0 | -44.5 -48.1  305  63 32   7.5   4.1
 25000 -41.9 -43.4  320  71 36   6.8   3.7 | -42.4 -44.3  310  63 32   7.2   4.0
 24000 -39.8 -39.6  320  69 36   6.8   3.7 | -40.2 -40.4  310  63 32   7.2   4.0
 23000 -37.8 -36.0  320  67 35   5.1   2.8 | -38.1 -36.6  310  63 32   6.0   3.3
 22000 -36.6 -33.9  320  62 32   4.2   2.3 | -36.5 -33.7  315  60 31   5.4   2.9
 21000 -35.3 -31.5  325  56 29   4.2   2.3 | -34.9 -30.8  315  57 30   5.4   2.9
 20000 -34.0 -29.2  325  50 26   5.2   2.8 | -33.2 -27.8  315  54 28   5.7   3.1
 19500 -33.2 -27.8  325  46 24   5.1   2.8 | -32.4 -26.3  315  51 26   5.7   3.1
 19000 -32.4 -26.3  320  43 22   5.1   2.8 | -31.5 -24.7  315  48 25   5.7   3.1
 18500 -31.7 -25.1  320  39 20   5.1   2.8 | -30.7 -23.3  320  45 23   5.7   3.1
 18000 -30.9 -23.6  320  36 19   4.9   2.7 | -29.8 -21.6  320  43 22   5.7   3.1
 17500 -30.3 -22.5  320  33 17   3.6   2.0 | -29.0 -20.2  320  40 21   5.4   3.0
 17000 -29.8 -21.6  315  30 15   3.5   1.9 | -28.2 -18.8  315  38 19   5.6   3.1
 16500 -29.1 -20.4  310  27 14   6.2   3.4 | -27.5 -17.5  315  35 18   3.8   2.1
 16000 -28.1 -18.6  305  24 12   6.2   3.4 | -26.9 -16.4  310  31 16   3.7   2.1
 15500 -26.6 -15.9  305  22 11   8.4   4.6 | -25.9 -14.6  305  26 13   5.7   3.1
 15000 -25.3 -13.5  305  21 11   8.2   4.5 | -25.1 -13.2  300  23 12   5.3   2.9
 14500 -24.1 -11.4  310  20 10   9.1   5.0 | -24.1 -11.4  295  20 10   8.5   4.7
 14000 -22.7  -8.9  310  20 10   9.1   5.0 | -22.9  -9.2  290  18 10   8.1   4.4
 13500 -21.4  -6.5  310  19 10   8.6   4.7 | -21.6  -6.9  290  17  9   9.4   5.2
 13000 -20.1  -4.2  310  19 10   8.6   4.7 | -20.2  -4.4  290  16  8   9.5   5.2
 12500 -18.9  -2.0  310  19 10   8.4   4.6 | -18.9  -2.0  290  15  8   8.3   4.6
 12000 -17.6   0.3  310  19 10   8.8   4.8 | -17.6   0.3  290  15  8   8.5   4.7
 11500 -16.6   2.1  305  18 10   4.9   2.7 | -16.5   2.3  290  14  7   6.6   3.6
 11000 -15.8   3.6  300  18  9   5.3   2.9 | -15.5   4.1  290  13  7   6.9   3.8
 10500 -15.3   4.5  295  16  8   1.6   0.9 | -14.8   5.4  285  11  6   3.0   1.6
 10250 -15.2   4.6  290  15  8   2.3   1.3 | -14.5   5.9  280  11  5   3.8   2.1
 10000 -15.0   5.0  280  14  7   1.2   0.7 | -14.3   6.3  275  10  5   2.3   1.2
  9750 -15.0   5.0  280  14  7   0.3   0.2 | -14.2   6.4  275  10  5   2.1   1.2
  9500 -15.0   5.0  275  12  6   0.8   0.5 | -13.9   7.0  265   9  4   3.3   1.8
  9250 -14.9   5.2  265   9  5   0.4   0.2 | -13.7   7.3  250   8  4   3.4   1.9
  9000 -14.9   5.2  255   8  4   1.9   1.0 | -13.5   7.7  235   7  4   1.8   1.0
  8750 -14.6   5.7  250   5  3   4.4   2.4 | -13.4   7.9  225   7  3   1.9   1.0
  8500 -14.3   6.3  245   4  2   5.0   2.7 | -13.2   8.2  215   6  3   4.3   2.4
  8250 -13.9   7.0  230   2  1   5.6   3.1 | -12.8   9.0  200   6  3   4.4   2.4
  8000 -13.4   7.9  205   1  1   6.7   3.7 | -12.5   9.5  190   6  3   5.0   2.7
  7750 -12.9   8.8  180   1  0   7.0   3.9 | -12.1  10.2  180   6  3   5.2   2.9
  7500 -12.4   9.7  155   1  1   6.8   3.8 | -11.7  10.9  170   5  3   4.7   2.6
  7250 -11.9  10.6  135   1  1   7.4   4.1 | -11.4  11.5  160   5  3   6.5   3.6
  7000 -11.3  11.7  120   2  1   7.9   4.3 | -10.8  12.6  140   5  3   8.2   4.5
  6750 -10.7  12.7  115   3  1   7.8   4.3 | -10.2  13.6  125   5  3   7.6   4.2
  6500 -10.1  13.8  110   4  2   8.0   4.4 |  -9.7  14.5  115   5  3   8.8   4.8
  6250  -9.5  14.9  105   4  2   8.1   4.5 |  -8.9  16.0  110   5  3  10.1   5.6
  6000  -9.0  15.8  105   4  2   8.2   4.5 |  -8.2  17.2  110   5  3   9.7   5.3
  5750  -8.4  16.9  100   4  2   8.0   4.4 |  -7.5  18.5  105   5  3  11.0   6.0
  5500  -7.8  18.0  100   4  2   7.3   4.0 |  -6.5  20.3  105   5  3  14.6   8.0

           02/26/2015 at 1400 MST          |       02/26/2015 at 1700 MST
                                           |
K index... +8.0  LI... +277.6              | K index... +9.3  LI... +277.4
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.8
                                           |
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 -52.6 -62.7  300  38 20   1.5   0.8 | -53.0 -63.4  305  40 21   1.6   0.9
 45000 -50.4 -58.7  300  48 25   1.5   0.8 | -50.7 -59.3  300  45 23   1.6   0.9
 40000 -48.9 -56.0  300  49 25   0.8   0.5 | -49.0 -56.2  300  47 24   1.0   0.5
 38000 -48.4 -55.1  300  49 25  -0.9  -0.5 | -48.5 -55.3  300  47 24   1.5   0.8
 36000 -51.3 -60.3  300  52 27  -5.0  -2.7 | -51.2 -60.2  300  50 26  -4.6  -2.5
 34000 -54.3 -65.7  300  55 28  -5.0  -2.8 | -53.9 -65.0  300  53 27  -4.6  -2.5
 32000 -55.0 -67.0  300  56 29   1.9   1.0 | -54.7 -66.5  295  54 28   1.0   0.6
 30000 -53.9 -65.0  300  56 29   1.8   1.0 | -54.1 -65.4  295  55 28   1.1   0.6
 29000 -53.0 -63.4  300  56 29   8.1   4.4 | -53.0 -63.4  295  56 29   8.5   4.7
 28000 -50.1 -58.2  300  58 30   7.7   4.2 | -50.6 -59.1  295  57 29   8.0   4.4
 27000 -47.8 -54.0  300  59 30   7.7   4.2 | -48.2 -54.8  295  58 30   8.0   4.4
 26000 -45.5 -49.9  300  60 31   7.6   4.2 | -45.8 -50.4  295  59 30   7.8   4.3
 25000 -43.2 -45.8  300  58 30   7.6   4.2 | -43.6 -46.5  295  57 29   7.5   4.1
 24000 -41.0 -41.8  300  57 29   7.6   4.2 | -41.3 -42.3  295  55 28   7.5   4.1
 23000 -38.7 -37.7  300  55 28   6.4   3.5 | -39.1 -38.4  295  53 27   6.6   3.6
 22000 -37.0 -34.6  300  52 27   5.8   3.2 | -37.4 -35.3  290  49 25   5.7   3.1
 21000 -35.2 -31.4  300  49 25   5.9   3.2 | -35.7 -32.3  290  46 23   5.6   3.1
 20000 -33.4 -28.1  300  46 24   6.7   3.7 | -33.8 -28.8  290  42 22   7.6   4.2
 19500 -32.4 -26.3  300  45 23   6.7   3.7 | -32.7 -26.9  290  41 21   7.4   4.1
 19000 -31.4 -24.5  300  44 23   6.7   3.7 | -31.6 -24.9  290  40 21   7.4   4.1
 18500 -30.4 -22.7  300  43 22   6.7   3.7 | -30.0 -22.0  290  39 20   7.4   4.1
 18000 -29.4 -20.9  300  42 22   6.5   3.6 | -28.9 -20.0  290  37 19   6.6   3.6
 17500 -28.6 -19.5  300  41 21   5.4   3.0 | -28.0 -18.4  290  37 19   6.3   3.4
 17000 -27.8 -18.0  300  39 20   5.4   2.9 | -27.0 -16.6  290  36 19   6.6   3.6
 16500 -26.9 -16.4  300  37 19   6.6   3.6 | -25.9 -14.6  290  35 18   8.0   4.4
 16000 -25.9 -14.6  300  35 18   6.5   3.6 | -24.7 -12.5  290  35 18   7.9   4.4
 15500 -24.9 -12.8  295  34 18   7.2   4.0 | -23.6 -10.5  285  33 17   7.8   4.3
 15000 -23.2  -9.8  285  33 17   7.5   4.1 | -22.4  -8.3  285  32 16   7.9   4.3
 14500 -22.1  -7.8  280  32 16   8.4   4.6 | -21.3  -6.3  285  29 15   7.1   3.9
 14000 -20.9  -5.6  280  29 15   8.5   4.6 | -20.2  -4.4  280  25 13   7.2   4.0
 13500 -19.8  -3.6  275  26 13   6.4   3.5 | -19.3  -2.7  280  21 11   4.8   2.6
 13000 -18.8  -1.8  275  22 11   6.5   3.6 | -18.6  -1.5  275  17  9   4.5   2.5
 12500 -17.9  -0.2  270  18  9   5.3   2.9 | -18.0  -0.4  265  13  7   4.1   2.2
 12000 -17.2   1.0  265  14  7   5.3   2.9 | -17.4   0.7  245  10  5   3.9   2.1
 11500 -16.4   2.5  255  11  6   4.8   2.6 | -16.7   1.9  220   9  5   5.7   3.1
 11000 -15.7   3.7  240   9  5   4.7   2.6 | -15.9   3.4  200   9  5   5.9   3.2
 10500 -14.9   5.2  225   8  4   5.4   3.0 | -15.0   5.0  185  10  5   6.1   3.4
 10250 -14.5   5.9  215   8  4   6.0   3.3 | -14.5   5.9  180   9  5   5.5   3.0
 10000 -14.1   6.6  210   9  5   3.3   1.8 | -14.1   6.6  170   9  5   7.9   4.3
  9750 -13.9   7.0  205   9  5   4.8   2.6 | -13.4   7.9  165  10  5   8.5   4.6
  9500 -13.4   7.9  195  10  5   8.5   4.6 | -12.9   8.8  160  10  5   6.4   3.5
  9250 -12.8   9.0  190  11  6   8.0   4.4 | -12.4   9.7  155  10  5   7.0   3.9
  9000 -12.2  10.0  180  13  7   6.1   3.4 | -11.9  10.6  150  11  5   6.5   3.6
  8750 -11.9  10.6  175  13  7   3.8   2.1 | -11.4  11.5  145  11  5   6.6   3.6
  8500 -11.6  11.1  170  12  6   4.5   2.4 | -10.9  12.4  135  11  6   6.9   3.8
  8250 -11.3  11.7  160  11  6   4.4   2.4 | -10.4  13.3  130  11  6   6.9   3.8
  8000 -10.9  12.4  150  10  5   4.3   2.4 |  -9.9  14.2  120  12  6   6.8   3.7
  7750 -10.6  12.9  135  10  5   4.8   2.6 |  -9.4  15.1  110  12  6   6.5   3.6
  7500 -10.3  13.5  120  10  5   4.6   2.5 |  -9.0  15.8  105  12  6   6.2   3.4
  7250  -9.9  14.2  110  10  5   6.6   3.6 |  -8.5  16.7  095  12  6   6.8   3.7
  7000  -9.3  15.3  100  10  5   9.2   5.0 |  -8.0  17.6  090  12  6   7.7   4.2
  6750  -8.6  16.5  095   9  5   8.4   4.6 |  -7.4  18.7  085  12  6   7.4   4.0
  6500  -8.0  17.6  085   9  4   8.9   4.9 |  -6.9  19.6  075  11  6   7.6   4.2
  6250  -7.3  18.9  085   8  4  10.3   5.7 |  -6.3  20.7  070  11  5   9.1   5.0
  6000  -6.5  20.3  080   8  4  10.6   5.8 |  -5.6  21.9  065  10  5   9.9   5.4
  5750  -5.8  21.6  080   8  4  10.5   5.8 |  -4.9  23.2  060   9  5   9.0   4.9
  5500  -4.9  23.2  080   7  4  12.5   6.8 |  -4.2  24.4  055   8  4   8.7   4.8
________________________________________________________________________________

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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