Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 181211
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0611 MDT Saturday, March 18, 2017

This forecast is for Saturday, March 18, 2017:

If the trigger temperature of 69.7 F/20.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1153 ft/min (5.9 m/s)
   Maximum height of thermals.................. 18096 ft MSL (12811 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 1145 MDT
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................. 13882 ft MSL (8597 ft AGL)
Thermal soaring outlook for Sunday 03/19....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 14386 ft MSL (9101 ft AGL)
Wave soaring outlook for Sunday 03/19.......... Poor

Remarks...

Sunrise/Sunset.................... 07:05:15 / 19:09:30 MDT
Total possible sunshine........... 12 hr 4 min 15 sec (724 min 15 sec)
Altitude of sun at 13:07:23 MDT... 49.53 degrees

Upper air data from rawinsonde observation taken on 03/18/2017 at 0600 MDT

Freezing level.................. 12962 ft MSL (7677 ft AGL)
Convective condensation level... 18640 ft MSL (13355 ft AGL)
Lifted condensation level....... 18693 ft MSL (13407 ft AGL)
Lifted index.................... +0.7
K index......................... +2.8

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  -65.8 -86.4   280   27   14  -1.2  -0.6   91.0 195.7    36.3      M    M
 45000  -72.9 -99.2   300   35   18 -40.0 -22.0   53.2 127.8    16.0      M    M
 40000  -66.9 -88.4   275   18    9   7.7   4.2   39.5 103.0     8.1      M    M
 38000  -62.1 -79.8   280   19   10   8.7   4.8   37.8 100.1     7.2      M    M
 36000  -56.5 -69.7   275   18    9   9.4   5.2   37.4  99.3     7.1      M    M
 34000  -50.9 -59.6   275   18    9   9.0   4.9   37.1  98.7     7.1      M    M
 32000  -45.5 -49.9   280   19   10   9.0   4.9   36.5  97.6     6.8      M    M
 30000  -39.5 -39.1   280   26   13   8.8   4.8   35.8  96.4     6.5      M    M
 29000  -36.9 -34.4   290   26   13   8.8   4.8   35.3  95.5     6.2      M    M
 28000  -34.3 -29.7   300   26   13   8.8   4.8   34.9  94.9     6.0      M    M
 27000  -31.6 -24.9   305   27   14   8.8   4.8   34.7  94.4     5.8      M    M
 26000  -29.0 -20.2   300   27   14   8.8   4.8   34.2  93.5     5.5      M    M
 25000  -26.4 -15.5   295   27   14   8.6   4.7   33.8  92.8     5.3      M    M
 24000  -24.1 -11.4   285   26   13   7.2   4.0   33.0  91.4     4.7      M    M
 23000  -21.9  -7.4   280   26   13   7.2   4.0   32.1  89.7     4.0      M    M
 22000  -19.8  -3.6   275   26   13   6.8   3.8   31.2  88.1     3.3      M    M
 21000  -17.7   0.1   280   25   13   6.9   3.8   30.1  86.2     2.4      M    M
 20000  -15.7   3.7   285   24   12   6.9   3.8   29.2  84.5     1.6      M    M
 19500  -14.7   5.5   285   21   11   6.9   3.8   28.6  83.6     1.2      M    M
 19000  -13.6   7.5   280   17    9   7.2   4.0   28.2  82.7     0.7      M    M
 18500  -12.5   9.5   280   16    8   7.4   4.1   27.7  81.9     0.4      M    M
 18000  -11.4  11.5   280   14    7   7.4   4.1   27.3  81.1    -0.0   1151  5.8
 17500  -10.3  13.5   280   13    7   7.4   4.1   26.9  80.5    -0.4   1104  5.6
 17000   -9.2  15.4   280   12    6   7.4   4.1   26.6  79.8    -0.7   1056  5.4
 16500   -8.1  17.4   285   11    5   7.4   4.1   26.2  79.2    -1.0   1008  5.1
 16000   -7.0  19.4   285    9    5   7.4   4.1   25.9  78.7    -1.3    961  4.9
 15500   -5.9  21.4   285    8    4   7.5   4.1   25.6  78.0    -1.7    913  4.6
 15000   -4.3  24.3   290    6    3   7.5   4.1   25.0  77.0    -2.2    841  4.3
 14500   -3.2  26.2   290    8    4   7.5   4.1   24.6  76.3    -2.6    794  4.0
 14000   -2.1  28.2   290   10    5   7.5   4.1   24.2  75.6    -3.0    746  3.8
 13500   -1.0  30.2   295   13    7   7.5   4.1   23.8  74.8    -3.4    698  3.5
 13000    0.1  32.2   295   17    9   7.5   4.1   23.4  74.1    -3.8    650  3.3
 12500    1.2  34.2   295   20   10   7.5   4.1   23.0  73.4    -4.2    603  3.1
 12000    2.3  36.1   295   23   12   8.1   4.5   22.7  72.8    -4.6    554  2.8
 11500    3.6  38.5   290   23   12   8.2   4.5   22.4  72.4    -4.9    502  2.6
 11000    4.8  40.6   285   23   12   8.2   4.5   22.2  72.0    -5.1    451  2.3
 10500    6.0  42.8   285   20   10   8.2   4.5   22.0  71.6    -5.4    400  2.0
 10250    6.6  43.9   285   19   10   8.2   4.5   21.8  71.3    -5.5    374  1.9
 10000    7.2  45.0   285   18   10   8.2   4.5   21.7  71.1    -5.7    349  1.8
  9750    7.8  46.0   285   18    9   8.2   4.5   21.6  70.9    -5.8    323  1.6
  9500    8.4  47.1   280   17    9   8.2   4.5   21.5  70.7    -5.9    297  1.5
  9250    9.0  48.2   280   16    8   8.2   4.5   21.4  70.5    -6.0    272  1.4
  9000    9.6  49.3   280   15    8   8.2   4.5   21.3  70.3    -6.2    246  1.3
  8750   10.3  50.5   280   14    7   8.2   4.5   21.1  70.1    -6.3    221  1.1
  8500   10.9  51.6   280   13    7   8.2   4.5   21.0  69.8    -6.5    195  1.0
  8250   11.5  52.7   285   13    7   8.2   4.5   20.9  69.6    -6.6    170  0.9
  8000   12.1  53.8   285   12    6   8.2   4.5   20.8  69.4    -6.7    144  0.7
  7750   12.7  54.9   280   11    6   8.2   4.5   20.6  69.2    -6.9    118  0.6
  7500   13.3  55.9   275   10    5   8.2   4.5   20.5  68.9    -7.1     93  0.5
  7250   13.9  57.0   270    9    5   8.1   4.4   20.4  68.7    -7.2     67  0.3
  7000   14.1  57.4   265    8    4  -5.8  -3.2   19.9  67.8    -7.7     53  0.3
  6750   12.6  54.7   255    7    3 -36.8 -20.2   17.6  63.6   -10.0     92  0.5
  6500    9.7  49.5   240    6    3 -21.4 -11.7   14.0  57.2   -13.6    170  0.9
  6250    9.5  49.1   225    5    3   3.0   1.7   13.1  55.5   -14.6    168  0.9
  6000    9.4  48.9   200    5    3  -4.3  -2.4   12.2  53.9   -15.5    166  0.8
  5750    9.2  48.6   200    3    2   0.8   0.4   11.3  52.3   -16.5    164  0.8
  5500    8.8  47.8   200    2    1 -18.7 -10.2   10.2  50.4   -17.6    167  0.9

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

           03/18/2017 at 0900 MDT          |       03/18/2017 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +4.4        | CAPE...     0.0    LI...       +3.6
CINH...    -0.2    K Index...  +2.7        | CINH...     0.0    K Index...  +4.1
                                           |
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 -67.6 -89.7  330  26 13  -2.2  -1.2 | -67.7 -89.9  330  26 13  -2.4  -1.3
 45000 -70.5 -94.9  320  22 11   3.5   1.9 | -70.7 -95.3  330  28 14   4.0   2.2
 40000 -65.7 -86.3  305  15  8   2.9   1.6 | -65.3 -85.5  295  14  7   3.4   1.9
 38000 -61.4 -78.5  270  12  6   8.2   4.5 | -60.9 -77.6  240  13  7   8.0   4.4
 36000 -56.4 -69.5  230  14  7   8.2   4.5 | -56.1 -69.0  210  22 11   8.0   4.4
 34000 -51.3 -60.3  220  17  9   8.8   4.8 | -51.1 -60.0  200  30 15   8.6   4.7
 32000 -46.1 -51.0  225  14  7   8.8   4.8 | -46.0 -50.8  200  33 17   8.6   4.7
 30000 -40.1 -40.2  245  11  6   8.8   4.8 | -40.1 -40.2  195  36 18   8.8   4.8
 29000 -37.5 -35.5  260  10  5   8.8   4.8 | -37.5 -35.5  195  36 19   8.8   4.8
 28000 -34.9 -30.8  275  10  5   8.8   4.8 | -34.9 -30.8  195  37 19   8.8   4.8
 27000 -32.3 -26.1  285  11  6   8.5   4.7 | -32.3 -26.1  195  36 18   8.5   4.7
 26000 -29.7 -21.5  290  12  6   8.5   4.7 | -29.7 -21.5  200  34 18   8.5   4.7
 25000 -27.2 -17.0  295  12  6   8.5   4.7 | -27.2 -17.0  200  33 17   8.5   4.7
 24000 -24.7 -12.5  295  13  6   8.1   4.4 | -24.7 -12.5  200  31 16   8.3   4.6
 23000 -22.3  -8.1  285  12  6   8.1   4.4 | -22.2  -8.0  200  29 15   8.3   4.6
 22000 -19.9  -3.8  280  12  6   8.1   4.4 | -19.7  -3.5  205  27 14   8.4   4.6
 21000 -17.6   0.3  270  11  6   7.6   4.2 | -17.4   0.7  205  26 13   7.4   4.1
 20000 -15.3   4.5  260  11  6   7.6   4.2 | -15.2   4.6  205  26 13   7.4   4.1
 19500 -14.2   6.4  255  11  6   7.6   4.2 | -14.1   6.6  205  26 13   7.4   4.1
 19000 -13.0   8.6  250  11  6   7.3   4.0 | -13.0   8.6  200  26 13   7.2   4.0
 18500 -12.0  10.4  250  10  5   7.0   3.9 | -11.9  10.6  200  25 13   7.0   3.9
 18000 -11.0  12.2  250  10  5   7.0   3.8 | -10.9  12.4  200  25 13   7.0   3.9
 17500  -9.9  14.2  250   9  5   7.0   3.9 |  -9.9  14.2  200  24 12   7.1   3.9
 17000  -8.4  16.9  260   8  4   7.1   3.9 |  -8.3  17.1  205  21 11   7.1   3.9
 16500  -7.3  18.9  280   8  4   7.1   3.9 |  -7.3  18.9  205  19 10   7.0   3.8
 16000  -6.3  20.7  300   8  4   7.1   3.9 |  -6.2  20.8  205  17  9   7.0   3.8
 15500  -5.2  22.6  320  10  5   7.4   4.0 |  -5.2  22.6  210  15  8   7.2   3.9
 15000  -4.1  24.6  335  15  8   7.4   4.1 |  -4.1  24.6  215  12  6   7.2   3.9
 14500  -3.0  26.6  345  20 10   7.6   4.1 |  -3.1  26.4  220  10  5   7.7   4.2
 14000  -1.9  28.6  350  27 14   7.7   4.2 |  -1.9  28.6  220   9  5   8.0   4.4
 13500  -0.8  30.6  355  34 17   7.8   4.3 |  -0.7  30.7  220   8  4   8.1   4.5
 13000   0.4  32.7  355  40 21   8.1   4.4 |   0.5  32.9  210   9  5   8.2   4.5
 12500   1.6  34.9  355  46 24   8.1   4.5 |   1.7  35.1  205  10  5   8.3   4.6
 12000   2.8  37.0  355  48 25   8.1   4.5 |   3.0  37.4  195  15  8   8.5   4.7
 11500   4.0  39.2  355  50 26   8.2   4.5 |   4.2  39.6  190  21 11   8.5   4.7
 11000   5.2  41.4  355  48 25   8.2   4.5 |   5.5  41.9  185  29 15   8.5   4.7
 10500   6.4  43.5  355  45 23   8.2   4.5 |   6.7  44.1  185  37 19   9.1   5.0
 10250   7.0  44.6  355  42 22   8.1   4.5 |   7.4  45.3  185  41 21   9.5   5.2
 10000   7.6  45.7  355  38 19   7.8   4.3 |   8.1  46.6  185  45 23   8.3   4.6
  9750   8.2  46.8  355  33 17   7.7   4.2 |   8.7  47.7  185  50 26   8.1   4.4
  9500   8.7  47.7  350  28 14   7.6   4.2 |   9.3  48.7  185  54 28   8.0   4.4
  9250   9.3  48.7  350  24 12   6.9   3.8 |   9.9  49.8  180  57 29   7.5   4.1
  9000   9.8  49.6  350  19 10   7.9   4.3 |  10.4  50.7  180  58 30   8.5   4.7
  8750  10.5  50.9  325   7  4   9.5   5.2 |  11.1  52.0  180  61 31   9.6   5.3
  8500  11.1  52.0  205   9  5   8.3   4.5 |  11.8  53.2  180  63 32   8.9   4.9
  8250  11.7  53.1  190  21 11   7.3   4.0 |  12.4  54.3  180  62 32   8.4   4.6
  8000  12.2  54.0  185  32 16   7.3   4.0 |  13.1  55.6  180  62 32   8.7   4.8
  7750  12.7  54.9  185  42 22   6.4   3.5 |  13.7  56.7  180  61 31   9.0   5.0
  7500  13.1  55.6  185  49 25   4.8   2.6 |  14.4  57.9  180  59 30   8.8   4.8
  7250  13.4  56.1  185  52 27   3.7   2.1 |  15.0  59.0  180  57 29   8.7   4.8
  7000  13.7  56.7  185  54 28   4.7   2.6 |  15.7  60.3  180  55 29   8.4   4.6
  6750  14.0  57.2  185  56 29   1.9   1.0 |  16.3  61.3  180  54 28   8.5   4.7
  6500  13.9  57.0  185  56 29  -2.8  -1.5 |  17.0  62.6  180  53 27   9.4   5.2
  6250  13.7  56.7  185  57 29  -2.2  -1.2 |  17.7  63.9  180  51 26   9.9   5.4
  6000  13.4  56.1  180  57 29  -5.8  -3.2 |  18.4  65.1  180  49 25   9.1   5.0
  5750  12.7  54.9  180  57 29 -10.2  -5.6 |  19.2  66.6  180  48 25  14.2   7.8
  5500  12.1  53.8  180  58 30  -6.3  -3.4 |  20.6  69.1  180  45 23  24.8  13.6

           03/18/2017 at 1500 MDT          |       03/18/2017 at 1800 MDT
                                           |
CAPE...     0.0    LI...       +2.3        | CAPE...    +3.1    LI...       +0.1
CINH...    -1.2    K Index... +12.4        | CINH...    -0.5    K Index... +19.0
                                           |
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 -67.4 -89.3  325  23 12  -2.3  -1.3 | -67.3 -89.1  315  19 10  -2.0  -1.1
 45000 -70.4 -94.7  330  30 15   4.1   2.3 | -69.8 -93.6  305  17  9   4.1   2.2
 40000 -64.7 -84.5  320  19 10   3.6   2.0 | -64.2 -83.6  305  17  9   3.6   2.0
 38000 -60.5 -76.9  265  12  6   7.7   4.2 | -60.0 -76.0  270  13  7   7.8   4.3
 36000 -55.9 -68.6  210  22 11   7.7   4.2 | -55.3 -67.5  220  18  9   7.8   4.3
 34000 -51.0 -59.8  200  34 18   8.6   4.7 | -50.5 -58.9  210  26 13   8.3   4.6
 32000 -45.2 -49.4  195  44 23   8.6   4.7 | -44.9 -48.8  205  31 16   8.3   4.6
 30000 -40.0 -40.0  195  49 25   8.7   4.8 | -39.9 -39.8  200  35 18   8.2   4.5
 29000 -37.4 -35.3  195  50 26   8.7   4.8 | -37.5 -35.5  200  37 19   8.2   4.5
 28000 -34.7 -30.5  195  51 26   8.8   4.8 | -35.1 -31.2  200  39 20   8.2   4.5
 27000 -32.2 -26.0  195  49 25   8.3   4.5 | -32.6 -26.7  200  39 20   8.1   4.4
 26000 -29.8 -21.6  195  47 24   8.3   4.5 | -30.2 -22.4  200  37 19   8.1   4.4
 25000 -27.3 -17.1  195  44 23   8.3   4.5 | -27.8 -18.0  200  35 18   8.1   4.4
 24000 -24.9 -12.8  195  43 22   8.1   4.4 | -25.5 -13.9  200  35 18   7.4   4.1
 23000 -22.4  -8.3  195  41 21   8.1   4.4 | -23.3  -9.9  200  35 18   7.4   4.1
 22000 -20.0  -4.0  195  40 20   8.1   4.4 | -21.1  -6.0  200  35 18   7.4   4.1
 21000 -17.8  -0.0  195  38 20   7.4   4.1 | -18.9  -2.0  195  39 20   7.3   4.0
 20000 -15.6   3.9  195  37 19   7.4   4.1 | -16.7   1.9  195  44 23   7.4   4.0
 19500 -14.5   5.9  195  37 19   7.4   4.1 | -15.7   3.7  190  46 24   7.4   4.1
 19000 -13.4   7.9  195  36 19   7.2   3.9 | -14.6   5.7  190  49 25   7.8   4.3
 18500 -12.4   9.7  195  36 18   6.9   3.8 | -13.4   7.9  190  53 27   8.4   4.6
 18000 -11.4  11.5  195  35 18   6.9   3.8 | -12.2  10.0  190  57 29   8.4   4.6
 17500  -9.9  14.2  195  35 18   6.9   3.8 | -10.3  13.5  185  60 31   8.8   4.8
 17000  -8.9  16.0  195  35 18   6.9   3.8 |  -9.0  15.8  185  61 32   8.8   4.8
 16500  -7.8  18.0  195  37 19   8.0   4.4 |  -7.7  18.1  185  62 32   8.9   4.9
 16000  -6.6  20.1  190  39 20   7.9   4.3 |  -6.3  20.7  185  62 32   8.8   4.8
 15500  -5.4  22.3  190  42 22   8.5   4.7 |  -5.0  23.0  185  62 32   9.2   5.1
 15000  -4.1  24.6  190  45 23   8.6   4.7 |  -3.6  25.5  185  61 31   9.3   5.1
 14500  -2.9  26.8  190  47 24   8.8   4.8 |  -2.2  28.0  185  60 31   9.4   5.2
 14000  -1.6  29.1  185  49 25   8.9   4.9 |  -0.8  30.6  185  58 30   9.5   5.2
 13500  -0.2  31.6  185  51 26   9.0   4.9 |   0.6  33.1  185  56 29   9.4   5.2
 13000   1.1  34.0  185  53 27   9.2   5.0 |   2.0  35.6  185  52 27   9.3   5.1
 12500   2.5  36.5  185  55 28   9.2   5.1 |   3.4  38.1  185  47 24   9.3   5.1
 12000   3.9  39.0  185  57 29   9.4   5.2 |   4.8  40.6  185  36 18   9.5   5.2
 11500   5.3  41.5  180  59 30   9.4   5.1 |   6.2  43.2  185  22 12   9.5   5.2
 11000   6.7  44.1  180  61 31   9.4   5.1 |   7.6  45.7  340   5  2   9.2   5.0
 10500   8.1  46.6  180  62 32   9.1   5.0 |   9.0  48.2  360  38 20   8.9   4.9
 10250   8.8  47.8  180  63 32   9.2   5.1 |   9.7  49.5  360  46 24   9.0   5.0
 10000   9.5  49.1  180  63 32   9.8   5.4 |  10.4  50.7  360  58 30   9.6   5.2
  9750  10.2  50.4  180  63 33   9.9   5.4 |  11.1  52.0  360  71 36   9.6   5.2
  9500  10.9  51.6  180  64 33   9.5   5.2 |  11.8  53.2  360  84 43   9.4   5.1
  9250  11.6  52.9  180  64 33   8.8   4.8 |  12.5  54.5  360  93 48   8.7   4.8
  9000  12.3  54.1  180  63 33   9.6   5.3 |  13.2  55.8  360  97 50   8.9   4.9
  8750  13.0  55.4  180  62 32  10.4   5.7 |  13.8  56.8  360 101 52   9.3   5.1
  8500  13.8  56.8  180  61 31  10.1   5.6 |  14.5  58.1  360 106 55   9.3   5.1
  8250  14.6  58.3  180  59 30  10.2   5.6 |  15.3  59.5  360 109 56   9.7   5.3
  8000  15.3  59.5  180  57 29   9.9   5.5 |  16.0  60.8  360 110 57   9.6   5.3
  7750  16.0  60.8  180  55 28   9.4   5.2 |  16.7  62.1  360 112 57   9.1   5.0
  7500  16.7  62.1  180  52 27  10.0   5.5 |  17.4  63.3  360 113 58   9.6   5.3
  7250  17.5  63.5  180  48 25  10.6   5.8 |  18.1  64.6  360 113 58  10.3   5.7
  7000  18.3  64.9  180  45 23  10.1   5.6 |  18.9  66.0  360 114 59  10.0   5.5
  6750  19.0  66.2  180  42 22   9.4   5.1 |  19.6  67.3  360 114 59   9.2   5.0
  6500  19.7  67.5  180  39 20   9.8   5.4 |  20.3  68.5  360 115 59   9.3   5.1
  6250  20.5  68.9  180  37 19  11.0   6.0 |  21.0  69.8  360 115 59   9.8   5.4
  6000  21.3  70.3  180  34 18   9.0   5.0 |  21.7  71.1  360 116 59   9.5   5.2
  5750  22.0  71.6  180  32 16  13.6   7.5 |  22.5  72.5  360 116 60  10.0   5.5
  5500  23.5  74.3  180  28 14  26.4  14.5 |  23.2  73.8  360 115 59  11.4   6.3
________________________________________________________________________________

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.

CINH (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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