Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 251212
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0612 MDT Wednesday, March 25, 2015

This forecast is for Wednesday, March 25, 2015:

If the trigger temperature of 48.8 F/9.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6432 ft MSL (1147 ft AGL)

Forecast maximum temperature................... 45.0 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 Thursday 03/26..... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... Showers through the day
Height of stable layer (12-18K ft MSL)......... 12431 ft MSL (7146 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 31402 ft MSL (26117 ft AGL)
Wave soaring outlook for Thursday 03/26........ Poor

Remarks...

Sunrise/Sunset.................... 06:55:08 / 19:15:22 MDT
Total possible sunshine........... 12 hr 20 min 14 sec (740 min 14 sec)
Altitude of sun at 13:05:25 MDT... 52.15 degrees

Upper air data from rawinsonde observation taken on 03/25/2015 at 0600 MDT

Freezing level.................. 7932 ft MSL (2647 ft AGL)
Convective condensation level... 12435 ft MSL (7150 ft AGL)
Lifted condensation level....... 10748 ft MSL (5463 ft AGL)
Lifted index.................... +7.3
K index......................... +16.0

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  -54.8 -66.6   285   31   16 -14.1  -7.7  110.1 230.2    58.6      M    M
 45000  -52.8 -63.0   290   24   12   2.6   1.4   88.5 191.3    49.5      M    M
 40000  -55.0 -67.0   275   45   23  -5.7  -3.1   61.6 143.0    35.5      M    M
 38000  -60.2 -76.4   265   59   30   5.2   2.9   44.9 112.7    25.2      M    M
 36000  -57.6 -71.7   260   61   31   2.7   1.5   40.2 104.3    22.7      M    M
 34000  -57.7 -71.9   260   63   32   3.7   2.0   31.5  88.7    17.2      M    M
 32000  -53.1 -63.6   260   67   35   5.5   3.0   28.8  83.9    15.7      M    M
 30000  -48.4 -55.1   255   66   34   9.3   5.1   27.3  81.1    15.0      M    M
 29000  -45.8 -50.4   255   64   33   9.4   5.2   26.8  80.3    14.9      M    M
 28000  -42.9 -45.2   255   62   32   9.7   5.3   26.8  80.3    15.0      M    M
 27000  -40.5 -40.9   260   60   31   6.4   3.5   26.1  79.0    14.7      M    M
 26000  -38.6 -37.5   260   59   30   7.7   4.2   24.8  76.7    13.8      M    M
 25000  -36.0 -32.8   260   57   29   8.8   4.8   24.4  76.0    13.7      M    M
 24000  -33.5 -28.3   260   57   29   8.3   4.5   23.9  75.0    13.4      M    M
 23000  -31.2 -24.2   260   53   27   7.4   4.1   23.1  73.5    12.9      M    M
 22000  -29.4 -20.9   265   49   25   5.5   3.0   21.8  71.2    11.9      M    M
 21000  -27.8 -18.0   265   46   23   5.1   2.8   20.2  68.4    10.8      M    M
 20000  -25.5 -13.9   270   42   22   8.4   4.6   19.5  67.1    10.3      M    M
 19500  -24.3 -11.7   270   41   21   8.4   4.6   19.2  66.6    10.1      M    M
 19000  -23.0  -9.4   265   39   20   8.4   4.6   19.0  66.2    10.0      M    M
 18500  -21.8  -7.2   270   34   18   8.4   4.6   18.8  65.8     9.8      M    M
 18000  -20.6  -5.1   280   29   15   7.6   4.2   18.5  65.2     9.5      M    M
 17500  -19.5  -3.1   285   25   13   7.7   4.2   18.1  64.6     9.3      M    M
 17000  -18.3  -0.9   295   21   11   7.7   4.2   17.8  64.0     9.0      M    M
 16500  -17.2   1.0   290   20   10   7.7   4.2   17.4  63.4     8.7      M    M
 16000  -15.5   4.1   280   20   10   7.7   4.2   16.9  62.4     8.3      M    M
 15500  -14.4   6.1   275   19   10   8.0   4.4   16.5  61.7     8.0      M    M
 15000  -13.4   7.9   270   18    9   5.0   2.8   16.0  60.8     7.6      M    M
 14500  -12.6   9.3   265   17    9   5.1   2.8   15.2  59.4     6.9      M    M
 14000  -11.9  10.6   260   16    8   5.1   2.8   14.5  58.0     6.2      M    M
 13500  -11.2  11.8   265   14    7   5.1   2.8   13.7  56.6     5.5      M    M
 13000  -10.4  13.3   265   11    6   5.3   2.9   12.9  55.3     4.8      M    M
 12500   -9.8  14.4   280    7    3   0.8   0.5   12.0  53.5     4.0      M    M
 12000   -9.0  15.8   325    4    2  10.3   5.6   11.3  52.3     3.4      M    M
 11500   -7.6  18.3   325    2    1   9.3   5.1   11.2  52.2     3.3      M    M
 11000   -6.2  20.8   130    1    0   9.2   5.1   11.1  52.0     3.3      M    M
 10500   -4.8  23.4   130    8    4   7.6   4.2   11.0  51.8     3.2      M    M
 10250   -4.4  24.1   130   12    6   6.1   3.4   10.7  51.3     3.0      M    M
 10000   -3.9  25.0   145   12    6   6.5   3.6   10.5  50.9     2.7      M    M
  9750   -3.4  25.9   135   12    6   6.5   3.5   10.2  50.4     2.5      M    M
  9500   -2.9  26.8   130   13    6   6.5   3.6   10.0  49.9     2.2      M    M
  9250   -2.5  27.5   120   13    7   6.5   3.6    9.7  49.5     2.0      M    M
  9000   -2.0  28.4   115   14    7   6.5   3.6    9.5  49.1     1.7      M    M
  8750   -1.5  29.3   110   12    6   6.5   3.6    9.2  48.6     1.4      M    M
  8500   -1.1  30.0   105   10    5   6.5   3.6    9.0  48.1     1.2      M    M
  8250   -0.6  30.9   100    8    4   6.5   3.6    8.7  47.7     0.9      M    M
  8000   -0.1  31.8   090    7    4   6.4   3.5    8.5  47.2     0.7      M    M
  7750    0.3  32.5   100    7    4   6.9   3.8    8.2  46.8     0.4      M    M
  7500    0.9  33.6   110    7    4   8.4   4.6    8.0  46.5     0.3      M    M
  7250    1.6  34.9   120    7    4   8.9   4.9    8.0  46.4     0.2      M    M
  7000    2.3  36.1   130    8    4   8.8   4.8    7.9  46.3     0.1      M    M
  6750    2.9  37.2   130    6    3   8.8   4.8    7.8  46.1     0.1      M    M
  6500    3.6  38.5   135    5    2   8.8   4.8    7.8  46.0     0.0      M    M
  6250    4.3  39.7   140    3    1   8.8   4.9    7.7  45.9    -0.0      M    M
  6000    4.9  40.8   165    1    1   8.8   4.8    7.6  45.8    -0.1      M    M
  5750    5.6  42.1   280    1    1   9.1   5.0    7.6  45.6    -0.2      M    M
  5500    6.2  43.2   300    3    2   7.7   4.2    7.5  45.5    -0.3      M    M

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

           03/25/2015 at 0900 MDT          |       03/25/2015 at 1200 MDT
                                           |
K index... +20.7  LI... +275.1             | K index... +16.6  LI... +275.2
CAPE... +16.3  CIN... -1.8                 | CAPE... +46.3  CIN... -4.5
                                           |
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 -54.0 -65.2  305  21 11   0.7   0.4 | -53.9 -65.0  305  17  9   0.9   0.5
 45000 -52.9 -63.2  290  24 12   0.7   0.4 | -52.6 -62.7  295  23 12   0.9   0.5
 40000 -54.1 -65.4  275  42 22  -0.9  -0.5 | -52.0 -61.6  285  40 21   0.3   0.2
 38000 -54.5 -66.1  270  48 25  -0.3  -0.2 | -51.8 -61.2  280  45 23   0.4   0.2
 36000 -54.7 -66.5  265  52 27  -0.3  -0.2 | -51.6 -60.9  275  46 23   0.4   0.2
 34000 -54.8 -66.6  255  57 29   0.4   0.2 | -51.3 -60.3  265  47 24   0.0   0.0
 32000 -51.9 -61.4  255  55 28   5.3   2.9 | -49.6 -57.3  255  52 27   3.2   1.7
 30000 -48.8 -55.8  250  53 27   6.1   3.3 | -47.5 -53.5  245  59 31   4.2   2.3
 29000 -46.5 -51.7  255  53 27   7.8   4.3 | -46.0 -50.8  245  57 29   4.9   2.7
 28000 -43.6 -46.5  255  54 28   7.8   4.3 | -44.6 -48.3  245  55 28   4.9   2.7
 27000 -41.3 -42.3  255  54 28   7.8   4.3 | -43.1 -45.6  245  52 27   4.9   2.7
 26000 -38.9 -38.0  255  53 27   7.9   4.4 | -41.5 -42.7  245  50 26   5.8   3.2
 25000 -36.6 -33.9  255  52 27   7.9   4.4 | -39.7 -39.5  245  49 25   5.8   3.2
 24000 -34.2 -29.6  260  50 26   8.0   4.4 | -38.0 -36.4  245  47 24   5.9   3.2
 23000 -32.0 -25.6  260  49 25   7.0   3.9 | -36.0 -32.8  245  44 23   7.5   4.1
 22000 -29.9 -21.8  260  47 24   7.0   3.9 | -33.7 -28.7  250  40 20   7.5   4.1
 21000 -27.8 -18.0  260  45 23   7.0   3.8 | -31.5 -24.7  250  36 18   7.5   4.1
 20000 -25.9 -14.6  265  43 22   6.5   3.6 | -28.8 -19.8  250  31 16   9.6   5.2
 19500 -24.9 -12.8  265  41 21   6.5   3.6 | -27.4 -17.3  250  29 15   9.6   5.2
 19000 -24.0 -11.2  265  40 21   6.5   3.6 | -26.0 -14.8  250  27 14   9.6   5.3
 18500 -23.0  -9.4  265  39 20   6.5   3.6 | -24.5 -12.1  250  25 13   9.9   5.4
 18000 -22.1  -7.8  270  37 19   6.3   3.4 | -23.3  -9.9  255  23 12   6.4   3.5
 17500 -21.2  -6.2  270  35 18   6.3   3.5 | -22.4  -8.3  260  22 11   6.8   3.7
 17000 -20.2  -4.4  270  33 17   6.1   3.3 | -21.4  -6.5  265  21 11   4.8   2.6
 16500 -19.4  -2.9  270  29 15   6.0   3.3 | -20.8  -5.4  275  22 11   4.0   2.2
 16000 -18.5  -1.3  275  25 13   5.9   3.2 | -20.3  -4.5  285  23 12   4.8   2.6
 15500 -17.6   0.3  275  21 11   5.8   3.2 | -18.8  -1.8  295  25 13   6.8   3.7
 15000 -16.3   2.7  285  16  8   6.5   3.6 | -17.8  -0.0  300  26 13   7.5   4.1
 14500 -15.3   4.5  290  14  7   6.8   3.7 | -16.6   2.1  305  25 13   7.7   4.2
 14000 -14.3   6.3  295  12  6   7.1   3.9 | -15.5   4.1  310  25 13   6.6   3.6
 13500 -13.2   8.2  305  11  6   7.4   4.1 | -14.7   5.5  315  24 12   5.6   3.1
 13000 -12.1  10.2  310  10  5   7.2   3.9 | -13.9   7.0  325  24 12   5.9   3.2
 12500 -11.1  12.0  310   8  4   6.7   3.7 | -12.9   8.8  330  24 12   6.4   3.5
 12000 -10.2  13.6  315   7  4   6.5   3.6 | -12.0  10.4  335  24 12   6.9   3.8
 11500  -9.3  15.3  315   6  3   6.3   3.5 | -10.9  12.4  335  24 12   7.5   4.1
 11000  -8.3  17.1  315   4  2   7.0   3.8 |  -9.8  14.4  340  24 12   7.7   4.2
 10500  -7.2  19.0  310   4  2   8.0   4.4 |  -8.6  16.5  345  24 12   8.2   4.5
 10250  -6.6  20.1  310   4  2   7.5   4.1 |  -8.0  17.6  345  24 12   6.8   3.7
 10000  -6.2  20.8  305   4  2   4.7   2.6 |  -7.7  18.1  345  24 12   4.5   2.5
  9750  -5.8  21.6  310   4  2   6.2   3.4 |  -7.2  19.0  345  23 12   7.6   4.2
  9500  -5.2  22.6  310   6  3   9.0   5.0 |  -6.5  20.3  345  23 12  10.5   5.7
  9250  -4.6  23.7  315   7  3   7.7   4.2 |  -5.8  21.6  345  22 11   8.7   4.8
  9000  -4.1  24.6  315   8  4   5.9   3.2 |  -5.3  22.5  345  22 11   6.9   3.8
  8750  -3.7  25.3  315   9  4   5.8   3.2 |  -4.8  23.4  350  21 11   7.7   4.2
  8500  -3.3  26.1  315   9  5   6.7   3.7 |  -4.1  24.6  350  20 11   8.9   4.9
  8250  -2.8  27.0  315  10  5   6.3   3.5 |  -3.5  25.7  350  20 10   7.8   4.3
  8000  -2.4  27.7  320  11  6   6.2   3.4 |  -3.0  26.6  350  19 10   7.5   4.1
  7750  -1.9  28.6  320  11  6   6.1   3.3 |  -2.4  27.7  350  18 10   6.6   3.6
  7500  -1.5  29.3  325  11  6   6.0   3.3 |  -2.0  28.4  350  18  9   5.8   3.2
  7250  -1.1  30.0  325  11  6   5.7   3.1 |  -1.6  29.1  350  16  8   6.5   3.6
  7000  -0.6  30.9  330  11  6   6.2   3.4 |  -1.1  30.0  355  14  7   6.6   3.6
  6750  -0.2  31.6  335  11  5   4.2   2.3 |  -0.7  30.7  355  11  6   6.5   3.6
  6500   0.0  32.0  340  10  5   6.5   3.6 |  -0.2  31.6  355   8  4   9.3   5.1
  6250   0.7  33.3  345   9  5  10.6   5.8 |   0.6  33.1  360   8  4  11.7   6.4
  6000   1.4  34.5  345   8  4   9.6   5.2 |   1.4  34.5  360   7  4  10.5   5.8
  5750   2.2  36.0  350   7  4  10.4   5.7 |   2.3  36.1  360   6  3  12.7   7.0
  5500   3.0  37.4  345   6  3  12.6   6.9 |   3.4  38.1  005   6  3  18.0   9.9

           03/25/2015 at 1500 MDT          |       03/25/2015 at 1800 MDT
                                           |
K index... +17.0  LI... +273.2             | K index... +9.2  LI... +274.5
CAPE... +61.9  CIN... -0.9                 | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -53.8 -64.8  305  22 12   1.6   0.9 | -54.5 -66.1  305  25 13   1.4   0.8
 45000 -51.3 -60.3  300  30 16   1.6   0.9 | -52.3 -62.1  305  29 15   1.3   0.7
 40000 -51.5 -60.7  300  37 19  -0.2  -0.1 | -52.1 -61.8  310  35 18   0.1   0.1
 38000 -51.4 -60.5  300  38 20   0.9   0.5 | -52.0 -61.6  315  37 19   0.0   0.0
 36000 -50.8 -59.4  300  36 19   1.0   0.5 | -52.0 -61.6  325  37 19   0.0   0.0
 34000 -50.3 -58.5  300  34 18   0.8   0.5 | -52.0 -61.6  330  38 20   0.1   0.0
 32000 -49.1 -56.4  295  31 16   2.0   1.1 | -50.5 -58.9  340  42 22   2.7   1.5
 30000 -47.8 -54.0  280  29 15   3.5   1.9 | -48.6 -55.5  350  47 24   6.0   3.3
 29000 -46.3 -51.3  270  28 15   4.8   2.6 | -46.5 -51.7  355  48 25   6.9   3.8
 28000 -44.9 -48.8  260  29 15   4.8   2.6 | -44.4 -47.9  355  49 25   6.9   3.8
 27000 -43.5 -46.3  250  31 16   4.8   2.6 | -42.4 -44.3  360  50 26   7.0   3.8
 26000 -41.9 -43.4  245  32 16   5.8   3.2 | -40.4 -40.7  360  47 24   6.1   3.3
 25000 -40.1 -40.2  240  32 16   5.8   3.2 | -38.6 -37.5  355  44 22   6.1   3.3
 24000 -38.4 -37.1  240  32 17   5.8   3.2 | -36.8 -34.2  355  40 21   6.1   3.3
 23000 -36.4 -33.5  240  31 16   7.2   4.0 | -34.9 -30.8  350  35 18   6.4   3.5
 22000 -34.2 -29.6  250  29 15   7.3   4.0 | -33.0 -27.4  335  32 16   6.4   3.5
 21000 -32.0 -25.6  260  27 14   7.3   4.0 | -31.1 -24.0  320  30 15   6.6   3.6
 20000 -29.8 -21.6  275  24 13   7.7   4.2 | -29.0 -20.2  320  28 15   7.3   4.0
 19500 -28.6 -19.5  285  23 12   7.7   4.2 | -27.9 -18.2  325  27 14   7.3   4.0
 19000 -27.5 -17.5  295  23 12   7.7   4.2 | -26.8 -16.2  325  27 14   7.3   4.0
 18500 -26.3 -15.3  305  23 12   7.7   4.2 | -25.7 -14.3  325  26 13   7.3   4.0
 18000 -25.2 -13.4  310  24 12   7.6   4.2 | -24.6 -12.3  330  25 13   7.4   4.1
 17500 -24.0 -11.2  315  24 12   7.6   4.2 | -23.5 -10.3  335  24 13   7.4   4.1
 17000 -22.9  -9.2  320  25 13   8.1   4.4 | -22.4  -8.3  340  24 12   7.5   4.1
 16500 -21.7  -7.1  325  25 13   8.1   4.5 | -21.3  -6.3  340  24 12   7.5   4.1
 16000 -20.0  -4.0  330  26 14   6.5   3.6 | -19.6  -3.3  345  23 12   7.3   4.0
 15500 -19.0  -2.2  335  27 14   6.7   3.6 | -18.6  -1.5  345  23 12   7.4   4.0
 15000 -18.0  -0.4  335  27 14   6.6   3.6 | -17.5   0.5  350  23 12   6.7   3.7
 14500 -17.0   1.4  340  28 14   6.5   3.6 | -16.5   2.3  350  23 12   6.7   3.7
 14000 -16.1   3.0  340  29 15   6.8   3.7 | -15.6   3.9  350  23 12   6.3   3.5
 13500 -15.0   5.0  340  29 15   7.0   3.8 | -14.7   5.5  355  23 12   6.2   3.4
 13000 -14.0   6.8  340  29 15   7.0   3.8 | -13.7   7.3  360  23 12   6.8   3.7
 12500 -13.0   8.6  340  29 15   7.0   3.9 | -12.7   9.1  360  23 12   7.1   3.9
 12000 -11.9  10.6  345  29 15   6.8   3.7 | -11.7  10.9  360  23 12   7.0   3.8
 11500 -11.0  12.2  345  27 14   6.6   3.6 | -10.6  12.9  360  23 12   6.9   3.8
 11000 -10.0  14.0  350  26 13   6.6   3.6 |  -9.6  14.7  005  22 11   7.3   4.0
 10500  -9.1  15.6  355  24 12   7.2   3.9 |  -8.5  16.7  005  19 10   7.9   4.3
 10250  -8.6  16.5  360  23 12   4.7   2.6 |  -8.0  17.6  005  17  9   5.1   2.8
 10000  -8.3  17.1  360  22 11   4.7   2.6 |  -7.7  18.1  010  16  8   4.6   2.5
  9750  -7.8  18.0  005  22 11  10.2   5.6 |  -7.2  19.0  010  15  7   9.3   5.1
  9500  -7.0  19.4  010  21 11  12.4   6.8 |  -6.5  20.3  010  13  7  10.9   6.0
  9250  -6.1  21.0  015  20 10  10.0   5.5 |  -5.7  21.7  015  11  6   9.1   5.0
  9000  -5.5  22.1  020  20 10   8.1   4.4 |  -5.2  22.6  015  11  6   7.9   4.3
  8750  -4.8  23.4  020  20 10  10.8   5.9 |  -4.5  23.9  015  11  6  10.7   5.9
  8500  -3.9  25.0  020  20 10  12.1   6.6 |  -3.6  25.5  015  11  6  11.5   6.3
  8250  -3.1  26.4  020  20 10  10.0   5.5 |  -2.9  26.8  015  11  6   9.6   5.3
  8000  -2.4  27.7  020  20 10   9.0   5.0 |  -2.2  28.0  015  11  6   8.7   4.8
  7750  -1.7  28.9  020  20 10   9.9   5.4 |  -1.5  29.3  015  11  6  10.7   5.9
  7500  -1.0  30.2  020  20 10  10.4   5.7 |  -0.6  30.9  015  11  6  10.8   5.9
  7250  -0.2  31.6  020  20 10  10.3   5.7 |   0.1  32.2  015  11  6   9.3   5.1
  7000   0.6  33.1  020  19 10  10.6   5.8 |   0.8  33.4  015  11  6   9.5   5.2
  6750   1.4  34.5  020  19 10   9.7   5.3 |   1.5  34.7  015  11  5  10.1   5.5
  6500   2.1  35.8  020  19 10   9.7   5.3 |   2.3  36.1  010  10  5  10.3   5.7
  6250   2.8  37.0  020  19 10  10.5   5.8 |   3.0  37.4  010  10  5   9.6   5.3
  6000   3.6  38.5  020  19 10  10.4   5.7 |   3.8  38.8  010  10  5  10.3   5.7
  5750   4.5  40.1  020  18  9  16.0   8.8 |   4.6  40.3  010  10  5  12.4   6.8
  5500   6.0  42.8  020  17  9  24.4  13.4 |   5.6  42.1  010   9  5  14.3   7.9
________________________________________________________________________________

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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