Soaring Guidance
Issued by NWS Denver/Boulder, CO

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058
UXUS97 KBOU 181248
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0547 MST Saturday, February 18, 2017

This forecast is for Saturday, February 18, 2017:

If the trigger temperature of 57.9 F/14.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 583 ft/min (3.0 m/s)
   Maximum height of thermals.................. 13482 ft MSL (8197 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... 1145 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9498 ft MSL (4213 ft AGL)
Thermal soaring outlook for Sunday 02/19....... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Becoming fair by 1200 MST as flo
Height of stable layer (12-18K ft MSL)......... 13416 ft MSL (8131 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 17604 ft MSL (12319 ft AGL)
Wave soaring outlook for Sunday 02/19.......... Poor

Remarks... Deep southwesterly flow becoming southerly ahead of western u. S.
           Trough.

Sunrise/Sunset.................... 06:47:22 / 17:39:20 MST
Total possible sunshine........... 10 hr 51 min 58 sec (651 min 58 sec)
Altitude of sun at 12:13:21 MST... 38.78 degrees

Upper air data from rawinsonde observation taken on 02/18/2017 at 0500 MST

Freezing level.................. 10523 ft MSL (5238 ft AGL)
Convective condensation level... 19957 ft MSL (14672 ft AGL)
Lifted condensation level....... 16795 ft MSL (11509 ft AGL)
Lifted index.................... +7.7
K index......................... +10.1

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  -62.0 -79.6   255   31   16   4.8   2.6   93.6 200.6    43.7      M    M
 45000  -54.7 -66.5   230   44   23   5.4   3.0   81.0 177.9    39.0      M    M
 40000  -46.7 -52.1   255   61   31   2.2   1.2   70.6 159.1    34.8      M    M
 38000  -47.6 -53.7   245   52   27  -2.6  -1.4   60.5 140.9    28.9      M    M
 36000  -56.6 -69.9   240   50   26 -31.2 -17.1   38.8 101.9    14.6      M    M
 34000  -53.2 -63.8   245   56   29   9.8   5.4   35.3  95.6    12.5      M    M
 32000  -46.7 -52.1   245   54   28   9.5   5.2   35.3  95.5    12.9      M    M
 30000  -41.3 -42.3   245   41   21   8.5   4.7   34.7  94.5    12.8      M    M
 29000  -38.7 -37.7   240   33   17   8.5   4.7   34.3  93.7    12.6      M    M
 28000  -36.2 -33.2   240   32   16   8.5   4.7   33.7  92.6    12.2      M    M
 27000  -33.6 -28.5   240   31   16   8.5   4.7   33.2  91.7    12.0      M    M
 26000  -31.0 -23.8   235   30   15   9.2   5.0   32.8  91.1    11.8      M    M
 25000  -28.3 -18.9   235   29   15   9.1   5.0   32.6  90.7    11.8      M    M
 24000  -25.8 -14.4   240   32   16   7.1   3.9   32.1  89.8    11.5      M    M
 23000  -24.0 -11.2   240   32   16   6.0   3.3   30.7  87.2    10.5      M    M
 22000  -22.2  -8.0   235   32   16   6.0   3.3   29.3  84.8     9.4      M    M
 21000  -20.3  -4.5   235   32   16   7.2   3.9   28.2  82.8     8.6      M    M
 20000  -18.2  -0.8   230   32   16   7.1   3.9   27.3  81.2     7.9      M    M
 19500  -17.1   1.2   230   32   16   7.1   3.9   26.8  80.3     7.5      M    M
 19000  -16.1   3.0   235   31   16   7.1   3.9   26.4  79.5     7.1      M    M
 18500  -15.0   5.0   235   31   16   7.1   3.9   25.9  78.7     6.8      M    M
 18000  -14.0   6.8   235   31   16   6.4   3.5   25.4  77.7     6.3      M    M
 17500  -13.1   8.4   240   32   17   6.4   3.5   24.8  76.7     5.9      M    M
 17000  -12.1  10.2   240   33   17   6.5   3.5   24.3  75.7     5.4      M    M
 16500  -11.2  11.8   245   31   16   6.5   3.5   23.7  74.7     4.9      M    M
 16000   -9.7  14.5   250   28   14   6.5   3.5   22.9  73.2     4.2      M    M
 15500   -8.8  16.2   255   27   14   6.5   3.6   22.3  72.1     3.7      M    M
 15000   -7.8  18.0   255   26   14   7.1   3.9   21.7  71.1     3.2      M    M
 14500   -7.2  19.0   260   26   13   1.0   0.5   20.8  69.5     2.4      M    M
 14000   -7.0  19.4   260   25   13   1.2   0.7   19.4  66.9     1.1      M    M
 13500   -6.8  19.8   270   23   12   0.9   0.5   18.0  64.4    -0.2    680  3.5
 13000   -6.4  20.5   275   22   11   7.3   4.0   16.9  62.5    -1.2    651  3.3
 12500   -5.1  22.8   270   19   10   8.7   4.8   16.8  62.2    -1.3    597  3.0
 12000   -3.8  25.2   270   17    9   8.8   4.8   16.6  61.9    -1.5    543  2.8
 11500   -2.5  27.5   270   13    7   8.8   4.8   16.5  61.6    -1.6    489  2.5
 11000   -1.1  30.0   265   10    5   8.7   4.8   16.3  61.4    -1.8    435  2.2
 10500    0.2  32.4   275   11    6   8.5   4.7   16.1  61.0    -2.0    381  1.9
 10250    0.8  33.4   280   11    6   9.8   5.4   16.0  60.9    -2.1    354  1.8
 10000    1.5  34.7   285   12    6   4.7   2.6   16.0  60.7    -2.1    327  1.7
  9750    1.6  34.9   285   11    5   2.9   1.6   15.3  59.6    -2.7    315  1.6
  9500    2.1  35.8   295    8    4   6.6   3.6   15.0  59.1    -3.0    294  1.5
  9250    2.5  36.5   305    6    3   5.6   3.1   14.7  58.5    -3.3    274  1.4
  9000    2.9  37.2   325    4    2   5.9   3.2   14.4  58.0    -3.6    253  1.3
  8750    3.4  38.1   315    3    2   5.8   3.2   14.1  57.4    -3.9    233  1.2
  8500    3.8  38.8   305    3    1   5.8   3.2   13.8  56.9    -4.2    212  1.1
  8250    4.3  39.7   285    2    1   5.8   3.2   13.5  56.3    -4.5    191  1.0
  8000    4.7  40.5   260    2    1   5.8   3.2   13.2  55.8    -4.8    171  0.9
  7750    5.1  41.2   235    2    1   5.8   3.2   12.9  55.2    -5.1    150  0.8
  7500    5.6  42.1   215    3    2   5.8   3.2   12.6  54.7    -5.4    129  0.7
  7250    6.0  42.8   205    4    2   5.8   3.2   12.3  54.1    -5.7    109  0.6
  7000    6.5  43.7   200    5    3   5.8   3.2   12.0  53.6    -6.0     88  0.4
  6750    6.9  44.4   200    5    3   5.8   3.2   11.7  53.0    -6.3     68  0.3
  6500    7.4  45.3   205    5    3   5.7   3.1   11.4  52.5    -6.7     47  0.2
  6250    7.8  46.0   205    6    3   6.1   3.3   11.1  51.9    -7.0     26  0.1
  6000    8.2  46.8   205    6    3   3.6   2.0   10.7  51.3    -7.3      7  0.0
  5750    8.2  46.8   205    4    2  -3.1  -1.7   10.0  50.1    -8.1      M    M
  5500    7.2  45.0   205    2    1 -30.2 -16.6    8.3  46.9    -9.8     23  0.1

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

           02/18/2017 at 0800 MST          |       02/18/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +2.9        | CAPE...     0.0    LI...       +2.7
CINH...    -0.1    K Index... +19.1        | CINH...    -0.1    K Index... +18.6
                                           |
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 -61.1 -78.0  230  17  9   4.6   2.5 | -61.5 -78.7  220  18  9   4.5   2.5
 45000 -54.0 -65.2  225  23 12   3.1   1.7 | -54.5 -66.1  220  26 14   3.0   1.6
 40000 -49.3 -56.7  240  28 14   3.2   1.7 | -49.9 -57.8  230  28 14   3.1   1.7
 38000 -49.4 -56.9  235  29 15  -3.0  -1.7 | -49.8 -57.6  225  29 15  -2.1  -1.2
 36000 -51.2 -60.2  230  29 15  -3.0  -1.7 | -51.1 -60.0  220  31 16  -2.1  -1.2
 34000 -51.4 -60.5  225  29 15   8.0   4.4 | -51.5 -60.7  215  33 17   8.7   4.8
 32000 -46.5 -51.7  225  27 14   8.3   4.6 | -46.4 -51.5  220  31 16   7.6   4.2
 30000 -41.5 -42.7  230  25 13   8.5   4.7 | -41.7 -43.1  220  29 15   8.4   4.6
 29000 -38.9 -38.0  235  24 12   8.5   4.7 | -39.1 -38.4  225  27 14   8.4   4.6
 28000 -36.4 -33.5  235  23 12   8.5   4.7 | -36.6 -33.9  225  25 13   8.4   4.6
 27000 -33.8 -28.8  240  22 11   8.0   4.4 | -34.1 -29.4  225  23 12   8.0   4.4
 26000 -31.6 -24.9  240  21 11   7.5   4.1 | -31.9 -25.4  230  22 11   7.5   4.1
 25000 -29.3 -20.7  240  20 10   7.5   4.1 | -29.6 -21.3  230  21 11   7.5   4.1
 24000 -27.1 -16.8  240  19 10   7.5   4.1 | -27.4 -17.3  230  19 10   7.5   4.1
 23000 -25.0 -13.0  240  18  9   6.9   3.8 | -25.3 -13.5  230  18  9   7.2   4.0
 22000 -23.0  -9.4  240  17  9   6.9   3.8 | -23.1  -9.6  230  18  9   7.2   4.0
 21000 -20.9  -5.6  240  16  8   7.0   3.8 | -21.0  -5.8  230  17  9   7.1   3.9
 20000 -18.9  -2.0  240  15  8   7.0   3.9 | -18.9  -2.0  225  17  9   6.9   3.8
 19500 -17.8  -0.0  240  15  8   7.0   3.9 | -17.9  -0.2  225  17  9   7.0   3.8
 19000 -16.8   1.8  240  15  8   7.0   3.9 | -16.9   1.6  225  17  9   7.0   3.8
 18500 -15.2   4.6  240  14  7   6.8   3.7 | -15.3   4.5  220  16  8   7.0   3.9
 18000 -14.3   6.3  235  14  7   6.7   3.7 | -14.3   6.3  220  16  8   7.1   3.9
 17500 -13.3   8.1  235  13  7   6.7   3.7 | -13.3   8.1  220  15  8   7.0   3.9
 17000 -12.3   9.9  235  13  6   6.5   3.5 | -12.3   9.9  220  15  8   6.6   3.6
 16500 -11.4  11.5  235  12  6   6.5   3.6 | -11.3  11.7  220  14  7   6.7   3.7
 16000 -10.4  13.3  235  11  6   6.2   3.4 | -10.3  13.5  220  13  7   6.2   3.4
 15500  -9.5  14.9  235  10  5   6.2   3.4 |  -9.4  15.1  215  13  7   6.2   3.4
 15000  -8.6  16.5  235   9  5   6.2   3.4 |  -8.5  16.7  215  12  6   6.0   3.3
 14500  -7.7  18.1  230   8  4   6.2   3.4 |  -7.7  18.1  210  11  6   5.9   3.3
 14000  -6.8  19.8  230   7  4   6.1   3.4 |  -6.8  19.8  210  10  5   6.1   3.3
 13500  -5.9  21.4  225   7  3   6.1   3.3 |  -5.9  21.4  205  10  5   6.3   3.5
 13000  -5.0  23.0  220   6  3   6.1   3.3 |  -5.0  23.0  200   9  5   6.4   3.5
 12500  -4.1  24.6  210   5  2   6.2   3.4 |  -4.0  24.8  195   8  4   7.0   3.8
 12000  -3.2  26.2  205   4  2   6.2   3.4 |  -2.9  26.8  190   8  4   7.0   3.8
 11500  -2.3  27.9  195   3  2   6.6   3.6 |  -1.8  28.8  180   8  4   7.6   4.2
 11000  -1.3  29.7  185   3  2   6.6   3.6 |  -0.7  30.7  175   7  4   7.6   4.1
 10500  -0.2  31.6  170   3  1   7.8   4.3 |   0.4  32.7  170   7  4   7.5   4.1
 10250   0.4  32.7  165   3  1   7.8   4.3 |   1.0  33.8  170   7  3   7.7   4.2
 10000   1.0  33.8  160   2  1   8.2   4.5 |   1.6  34.9  165   6  3   8.5   4.7
  9750   1.6  34.9  155   2  1   9.0   4.9 |   2.2  36.0  165   6  3   8.7   4.8
  9500   2.3  36.1  155   2  1   9.0   4.9 |   2.9  37.2  165   6  3   8.4   4.6
  9250   3.0  37.4  150   1  1   9.6   5.3 |   3.5  38.3  160   5  3   9.1   5.0
  9000   3.7  38.7  140   1  0   7.2   3.9 |   4.2  39.6  160   5  3   6.7   3.7
  8750   4.1  39.4  130   1  0   5.8   3.2 |   4.5  40.1  160   5  2   5.5   3.0
  8500   4.6  40.3  000   0  0   7.2   4.0 |   5.0  41.0  160   4  2   7.0   3.8
  8250   5.1  41.2  000   0  0   7.1   3.9 |   5.5  41.9  155   4  2   6.8   3.7
  8000   5.6  42.1  000   0  0   6.4   3.5 |   6.0  42.8  155   3  2   6.0   3.3
  7750   6.1  43.0  355   1  0   5.8   3.2 |   6.4  43.5  150   3  2   5.7   3.1
  7500   6.5  43.7  355   1  0   6.4   3.5 |   6.9  44.4  150   3  1   6.5   3.5
  7250   7.0  44.6  350   1  1   5.9   3.3 |   7.4  45.3  150   2  1   6.1   3.3
  7000   7.4  45.3  345   1  1   4.4   2.4 |   7.8  46.0  150   2  1   4.7   2.6
  6750   7.7  45.9  340   1  1   2.5   1.4 |   8.1  46.6  160   2  1   5.5   3.0
  6500   7.9  46.2  330   1  1   3.3   1.8 |   8.6  47.5  160   2  1   6.8   3.7
  6250   8.1  46.6  315   1  1  -0.5  -0.3 |   9.1  48.4  160   2  1   6.8   3.7
  6000   7.8  46.0  300   1  1  -5.5  -3.0 |   9.7  49.5  165   2  1   7.2   3.9
  5750   7.4  45.3  290   1  1  -4.9  -2.7 |  10.2  50.4  165   1  1   7.9   4.4
  5500   6.8  44.2  250   1  1 -11.5  -6.3 |  11.0  51.8  165   1  1  14.1   7.7

           02/18/2017 at 1400 MST          |       02/18/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +2.9        | CAPE...    +0.9    LI...       +1.7
CINH...    -0.1    K Index... +18.2        | CINH...    -3.8    K Index... +21.0
                                           |
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 -61.1 -78.0  220  20 10   4.3   2.4 | -61.0 -77.8  215  19 10   4.3   2.3
 45000 -54.4 -65.9  220  27 14   3.0   1.6 | -54.4 -65.9  220  26 14   2.6   1.4
 40000 -49.9 -57.8  220  29 15   3.1   1.7 | -50.3 -58.5  215  31 16   2.8   1.5
 38000 -49.7 -57.5  220  31 16  -1.9  -1.1 | -50.0 -58.0  215  34 17  -1.4  -0.7
 36000 -50.9 -59.6  215  34 18  -1.9  -1.1 | -50.8 -59.4  215  37 19  -1.4  -0.7
 34000 -51.3 -60.3  215  36 19   8.6   4.7 | -51.0 -59.8  215  39 20   8.3   4.5
 32000 -46.2 -51.2  215  33 17   7.5   4.1 | -46.1 -51.0  215  35 18   7.2   4.0
 30000 -41.6 -42.9  215  30 16   8.3   4.6 | -41.5 -42.7  210  32 16   8.5   4.7
 29000 -39.1 -38.4  215  29 15   8.3   4.6 | -39.0 -38.2  210  31 16   8.5   4.7
 28000 -36.6 -33.9  215  27 14   8.3   4.6 | -36.5 -33.7  210  29 15   8.5   4.7
 27000 -34.1 -29.4  215  25 13   8.1   4.4 | -33.9 -29.0  210  28 14   8.1   4.4
 26000 -31.8 -25.2  215  24 12   7.8   4.3 | -31.7 -25.1  210  27 14   7.6   4.1
 25000 -29.5 -21.1  215  23 12   7.8   4.3 | -29.4 -20.9  210  27 14   7.6   4.2
 24000 -27.2 -17.0  215  22 11   7.8   4.3 | -27.2 -17.0  210  27 14   7.6   4.2
 23000 -25.0 -13.0  215  21 11   7.5   4.1 | -25.0 -13.0  210  26 13   7.2   3.9
 22000 -22.7  -8.9  215  20 10   7.5   4.1 | -22.9  -9.2  210  24 12   7.2   4.0
 21000 -20.5  -4.9  210  19 10   7.4   4.1 | -20.7  -5.3  210  23 12   7.2   4.0
 20000 -18.4  -1.1  210  19 10   7.2   4.0 | -18.6  -1.5  210  22 11   7.3   4.0
 19500 -17.3   0.9  210  19 10   7.2   4.0 | -17.5   0.5  210  22 11   7.3   4.0
 19000 -16.2   2.8  210  20 10   7.2   4.0 | -16.4   2.5  210  22 11   7.3   4.0
 18500 -14.6   5.7  210  20 10   6.9   3.8 | -15.3   4.5  210  22 11   7.3   4.0
 18000 -13.7   7.3  210  19 10   6.7   3.7 | -13.9   7.0  210  22 11   6.3   3.5
 17500 -12.7   9.1  210  19 10   6.7   3.7 | -13.0   8.6  210  21 11   6.3   3.5
 17000 -11.7  10.9  210  18  9   6.3   3.4 | -12.1  10.2  210  21 11   6.2   3.4
 16500 -10.8  12.6  205  17  9   6.3   3.5 | -11.2  11.8  210  20 10   6.2   3.4
 16000  -9.9  14.2  205  16  8   6.3   3.5 | -10.2  13.6  205  20 10   6.3   3.5
 15500  -8.9  16.0  205  16  8   6.3   3.5 |  -9.3  15.3  205  19 10   6.4   3.5
 15000  -8.0  17.6  205  15  8   6.3   3.4 |  -8.4  16.9  205  18  9   6.6   3.6
 14500  -7.1  19.2  200  14  7   6.2   3.4 |  -7.4  18.7  205  16  8   6.8   3.7
 14000  -6.2  20.8  200  13  7   6.1   3.4 |  -6.4  20.5  205  15  8   6.9   3.8
 13500  -5.4  22.3  200  12  6   5.7   3.1 |  -5.4  22.3  200  14  7   7.1   3.9
 13000  -4.6  23.7  195  12  6   5.7   3.1 |  -4.3  24.3  200  12  6   7.1   3.9
 12500  -3.6  25.5  190  11  5   6.5   3.6 |  -3.3  26.1  195  11  6   7.5   4.1
 12000  -2.7  27.1  185  10  5   6.3   3.5 |  -2.2  28.0  195  10  5   7.4   4.1
 11500  -1.6  29.1  180   9  5   8.0   4.4 |  -1.0  30.2  190   9  5   8.5   4.7
 11000  -0.4  31.3  175   8  4   7.9   4.4 |   0.3  32.5  185   9  4   8.4   4.6
 10500   0.7  33.3  170   7  4   6.5   3.6 |   1.5  34.7  185   8  4   8.1   4.4
 10250   1.2  34.2  165   7  4   8.3   4.5 |   2.1  35.8  185   8  4   9.2   5.0
 10000   1.9  35.4  165   7  3  11.0   6.0 |   2.9  37.2  185   8  4  10.7   5.9
  9750   2.7  36.9  160   6  3  10.7   5.9 |   3.7  38.7  180   8  4  10.4   5.7
  9500   3.5  38.3  160   6  3  10.0   5.5 |   4.4  39.9  180   8  4  10.1   5.6
  9250   4.3  39.7  155   6  3  10.5   5.8 |   5.2  41.4  180   7  4  10.4   5.7
  9000   5.0  41.0  155   6  3   8.2   4.5 |   5.9  42.6  180   7  4   7.5   4.1
  8750   5.6  42.1  155   5  3   8.0   4.4 |   6.4  43.5  180   8  4   7.8   4.3
  8500   6.3  43.3  150   5  3   9.9   5.4 |   7.1  44.8  180   7  4  10.2   5.6
  8250   7.0  44.6  150   5  3   9.4   5.1 |   7.9  46.2  180   7  4   9.7   5.3
  8000   7.7  45.9  150   5  2   9.7   5.3 |   8.6  47.5  175   7  4   9.1   5.0
  7750   8.4  47.1  145   5  2   9.8   5.4 |   9.2  48.6  175   7  4   9.0   5.0
  7500   9.2  48.6  145   4  2   9.8   5.4 |  10.0  50.0  175   7  4   9.7   5.3
  7250   9.9  49.8  145   4  2   9.8   5.4 |  10.7  51.3  175   7  4   9.6   5.3
  7000  10.6  51.1  140   4  2   9.6   5.3 |  11.4  52.5  175   7  4   9.4   5.2
  6750  11.3  52.3  140   4  2   9.9   5.5 |  12.1  53.8  175   7  3   9.4   5.1
  6500  12.1  53.8  140   4  2  10.3   5.7 |  12.8  55.0  175   6  3   9.6   5.3
  6250  12.9  55.2  135   4  2  10.2   5.6 |  13.5  56.3  170   6  3   9.5   5.2
  6000  13.6  56.5  135   4  2  10.8   5.9 |  14.3  57.7  170   6  3  10.2   5.6
  5750  14.4  57.9  135   3  2   8.9   4.9 |  15.0  59.0  170   5  3   7.8   4.3
  5500  15.1  59.2  135   3  2  11.5   6.3 |  15.3  59.5  170   4  2   2.3   1.2
________________________________________________________________________________

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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