Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 251223
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0623 MDT Thursday, May 25, 2017

This forecast is for Thursday, May 25, 2017:

If the trigger temperature of 74.3 F/23.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 508 ft/min (2.6 m/s)
   Maximum height of thermals.................. 13375 ft MSL (8090 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8183 ft MSL (2898 ft AGL)
Thermal soaring outlook for Friday 05/26....... Fair

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 14408 ft MSL (9123 ft AGL)
Wave soaring outlook for Friday 05/26.......... Poor

Remarks...

Sunrise/Sunset.................... 05:36:42 / 20:16:15 MDT
Total possible sunshine........... 14 hr 39 min 33 sec (879 min 33 sec)
Altitude of sun at 12:56:28 MDT... 71.30 degrees

Upper air data from rawinsonde observation taken on 05/25/2017 at 0600 MDT

Freezing level.................. 13886 ft MSL (8601 ft AGL)
Convective condensation level... 15703 ft MSL (10418 ft AGL)
Lifted condensation level....... 15404 ft MSL (10119 ft AGL)
Lifted index.................... -2.7
K index......................... +21.1

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  -63.8 -82.8   275   28   14   4.2   2.3   89.5 193.1    36.9      M    M
 45000  -60.7 -77.3   245   55   28  -1.6  -0.9   70.4 158.6    27.7      M    M
 40000  -58.1 -72.6   240   75   39   5.1   2.8   51.4 124.5    17.1      M    M
 38000  -54.1 -65.4   245   71   36   7.1   3.9   48.4 119.0    15.5      M    M
 36000  -49.9 -57.8   245   66   34   6.6   3.6   46.3 115.3    14.5      M    M
 34000  -45.2 -49.4   250   65   34   7.9   4.3   43.7 110.6    13.1      M    M
 32000  -41.3 -42.3   240   55   28   4.6   2.5   40.8 105.5    11.3      M    M
 30000  -37.8 -36.0   230   46   24   4.3   2.4   37.7  99.8     9.2      M    M
 29000  -36.9 -34.4   225   38   20   3.2   1.8   35.0  95.0     7.2      M    M
 28000  -35.2 -31.4   215   31   16   8.5   4.7   33.5  92.4     6.2      M    M
 27000  -32.6 -26.7   205   24   12   8.7   4.8   33.2  91.8     6.0      M    M
 26000  -29.9 -21.8   210   23   12   8.7   4.8   32.8  91.0     5.7      M    M
 25000  -27.4 -17.3   215   22   11   7.9   4.3   32.4  90.3     5.4      M    M
 24000  -25.1 -13.2   225   21   11   7.9   4.3   31.6  88.9     4.8      M    M
 23000  -22.3  -8.1   235   24   12   9.6   5.3   31.3  88.4     4.6      M    M
 22000  -19.4  -2.9   240   26   14   9.6   5.3   31.2  88.2     4.6      M    M
 21000  -16.5   2.3   245   29   15   9.6   5.3   31.2  88.2     4.6      M    M
 20000  -14.1   6.6   250   33   17   4.4   2.4   30.8  87.4     4.3      M    M
 19500  -13.4   7.9   250   36   19   4.8   2.7   29.9  85.8     3.6      M    M
 19000  -12.6   9.3   255   40   21   4.2   2.3   29.0  84.3     2.8      M    M
 18500  -11.5  11.3   255   44   23   9.6   5.2   28.6  83.6     2.5      M    M
 18000  -10.4  13.3   255   44   23   8.0   4.4   28.3  82.9     2.1      M    M
 17500   -9.2  15.4   260   45   23   7.9   4.3   27.9  82.3     1.8      M    M
 17000   -8.1  17.4   260   45   23   7.9   4.3   27.6  81.7     1.5      M    M
 16500   -6.4  20.5   265   46   23   7.9   4.3   27.2  81.0     1.1      M    M
 16000   -5.1  22.8   265   46   24   8.6   4.7   27.0  80.6     0.9      M    M
 15500   -3.9  25.0   270   47   24   8.6   4.7   26.8  80.2     0.7      M    M
 15000   -2.6  27.3   270   47   24   8.6   4.7   26.6  79.9     0.5      M    M
 14500   -1.3  29.7   275   48   25   8.6   4.7   26.5  79.7     0.4      M    M
 14000   -0.1  31.8   275   49   25   8.6   4.7   26.3  79.4     0.2      M    M
 13500    1.2  34.2   275   46   24   8.6   4.7   26.1  79.0     0.0      M    M
 13000    2.5  36.5   275   44   23   8.6   4.7   25.9  78.7    -0.2    660  3.4
 12500    3.7  38.7   270   42   22   8.6   4.7   25.8  78.4    -0.4    607  3.1
 12000    5.0  41.0   270   39   20   8.6   4.7   25.6  78.1    -0.5    555  2.8
 11500    6.3  43.3   270   35   18   8.6   4.7   25.4  77.7    -0.8    502  2.5
 11000    7.5  45.5   265   30   16   8.6   4.7   25.2  77.3    -1.0    449  2.3
 10500    8.8  47.8   265   26   13   8.6   4.7   25.0  77.0    -1.2    396  2.0
 10250    9.4  48.9   260   24   12   8.7   4.8   24.9  76.8    -1.3    370  1.9
 10000   10.1  50.2   260   22   11   8.4   4.6   24.8  76.7    -1.4    343  1.7
  9750   10.6  51.1   260   21   11   7.3   4.0   24.6  76.4    -1.6    319  1.6
  9500   11.2  52.2   265   20   10   6.9   3.8   24.4  76.0    -1.8    296  1.5
  9250   11.7  53.1   265   18    9   7.0   3.8   24.2  75.6    -2.0    274  1.4
  9000   12.2  54.0   270   17    9   7.0   3.8   24.0  75.2    -2.3    251  1.3
  8750   12.7  54.9   275   16    8   7.0   3.8   23.8  74.8    -2.5    228  1.2
  8500   13.2  55.8   275   15    8   7.0   3.8   23.6  74.5    -2.7    206  1.0
  8250   13.7  56.7   280   14    7   7.0   3.8   23.4  74.1    -2.9    183  0.9
  8000   14.2  57.6   285   13    7   7.0   3.8   23.2  73.7    -3.2    161  0.8
  7750   14.7  58.5   290   13    7   7.0   3.8   23.0  73.3    -3.4    138  0.7
  7500   15.2  59.4   290   12    6   7.0   3.8   22.7  72.9    -3.6    115  0.6
  7250   15.7  60.3   295   12    6   7.0   3.8   22.5  72.6    -3.9     93  0.5
  7000   16.2  61.2   300   12    6   7.0   3.8   22.3  72.2    -4.1     70  0.4
  6750   16.7  62.1   305   13    7   7.0   3.8   22.1  71.8    -4.3     48  0.2
  6500   17.2  63.0   305   14    7   7.0   3.8   21.9  71.4    -4.6     25  0.1
  6250   17.7  63.9   310   15    8   7.2   3.9   21.7  71.0    -4.8      2  0.0
  6000   18.2  64.8   310   16    8   6.4   3.5   21.5  70.6    -5.1      M    M
  5750   18.8  65.8   310   12    6   9.4   5.1   21.3  70.3    -5.3      M    M
  5500   19.3  66.7   305    7    4  -1.4  -0.8   21.0  69.9    -5.6      M    M

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

           05/25/2017 at 0900 MDT          |       05/25/2017 at 1200 MDT
                                           |
CAPE...  +208.2    LI...       +0.8        | CAPE...  +422.2    LI...       -1.6
CINH...  -114.4    K Index... +17.3        | CINH...    -5.2    K Index... +25.5
                                           |
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 -60.7 -77.3  245  21 11   0.9   0.5 | -60.0 -76.0  250  20 10   1.4   0.8
 45000 -59.2 -74.6  245  35 18   1.5   0.8 | -57.9 -72.2  245  32 16   1.5   0.8
 40000 -57.1 -70.8  235  37 19   1.5   0.8 | -55.7 -68.3  240  34 17   1.4   0.8
 38000 -54.8 -66.6  235  36 18   5.1   2.8 | -54.0 -65.2  240  32 17   3.7   2.0
 36000 -51.7 -61.1  235  33 17   5.1   2.8 | -51.5 -60.7  245  30 15   3.7   2.0
 34000 -48.0 -54.4  235  29 15   6.3   3.5 | -48.8 -55.8  245  26 13   6.0   3.3
 32000 -44.2 -47.6  240  24 12   6.3   3.5 | -45.2 -49.4  240  20 10   6.0   3.3
 30000 -40.2 -40.4  240  20 10   7.5   4.1 | -41.2 -42.2  240  16  8   8.0   4.4
 29000 -38.0 -36.4  240  18  9   7.4   4.1 | -38.8 -37.8  240  15  8   8.0   4.4
 28000 -35.7 -32.3  240  17  9   7.4   4.1 | -36.4 -33.5  240  14  7   8.0   4.4
 27000 -33.5 -28.3  240  16  8   8.4   4.6 | -34.0 -29.2  240  14  7   8.3   4.5
 26000 -30.9 -23.6  240  16  8   8.4   4.6 | -31.5 -24.7  245  15  7   8.3   4.6
 25000 -28.4 -19.1  245  16  8   8.4   4.6 | -29.0 -20.2  250  15  8   8.3   4.6
 24000 -25.9 -14.6  245  17  9   8.6   4.7 | -26.6 -15.9  250  16  8   8.2   4.5
 23000 -23.3  -9.9  245  17  9   8.7   4.8 | -24.2 -11.6  255  18  9   8.0   4.4
 22000 -20.7  -5.3  245  18  9   8.7   4.8 | -21.8  -7.2  255  19 10   8.1   4.4
 21000 -18.1  -0.6  245  18  9   8.5   4.6 | -19.4  -2.9  255  21 11   8.0   4.4
 20000 -15.6   3.9  250  18 10   8.4   4.6 | -17.0   1.4  255  21 11   8.0   4.4
 19500 -14.4   6.1  250  19 10   8.4   4.6 | -15.8   3.6  255  21 11   8.0   4.4
 19000 -13.1   8.4  250  19 10   8.4   4.6 | -14.1   6.6  260  21 11   8.0   4.4
 18500 -11.9  10.6  250  19 10   8.2   4.5 | -12.9   8.8  260  20 11   8.1   4.4
 18000 -10.7  12.7  255  19 10   8.0   4.4 | -11.7  10.9  260  20 10   8.1   4.5
 17500  -8.9  16.0  255  19 10   8.0   4.4 | -10.5  13.1  260  19 10   8.3   4.6
 17000  -7.7  18.1  260  19 10   8.0   4.4 |  -9.2  15.4  260  18  9   8.5   4.6
 16500  -6.5  20.3  260  19 10   8.0   4.4 |  -8.0  17.6  255  17  9   8.5   4.7
 16000  -5.3  22.5  260  20 10   7.9   4.3 |  -6.7  19.9  255  16  8   9.0   5.0
 15500  -4.2  24.4  265  21 11   7.9   4.3 |  -5.4  22.3  255  15  8   9.0   4.9
 15000  -3.0  26.6  265  21 11   7.5   4.1 |  -4.0  24.8  255  14  7   9.0   4.9
 14500  -1.9  28.6  265  21 11   7.5   4.1 |  -2.7  27.1  255  13  7   9.0   5.0
 14000  -0.8  30.6  270  20 10   7.7   4.2 |  -1.4  29.5  255  13  6   9.4   5.1
 13500   0.3  32.5  270  20 10   7.8   4.3 |   0.1  32.2  255  12  6   9.6   5.3
 13000   1.5  34.7  270  19 10   8.0   4.4 |   1.5  34.7  255  11  5   9.6   5.2
 12500   2.7  36.9  270  17  9   8.3   4.5 |   2.9  37.2  255  10  5   9.4   5.2
 12000   3.9  39.0  275  16  8   8.3   4.6 |   4.3  39.7  255   9  5   9.4   5.2
 11500   5.1  41.2  275  15  7   8.8   4.8 |   5.7  42.3  255   8  4   9.4   5.2
 11000   6.4  43.5  275  13  7   8.6   4.7 |   7.1  44.8  255   8  4   9.2   5.1
 10500   7.6  45.7  275  12  6   7.0   3.8 |   8.4  47.1  255   7  3   8.2   4.5
 10250   8.2  46.8  275  11  6   9.4   5.2 |   9.0  48.2  260   6  3  10.1   5.5
 10000   9.0  48.2  275  10  5  11.1   6.1 |   9.9  49.8  260   6  3  11.2   6.2
  9750   9.7  49.5  275  10  5   9.5   5.2 |  10.7  51.3  260   6  3  10.6   5.8
  9500  10.4  50.7  275   9  4   9.2   5.0 |  11.4  52.5  265   5  3  10.8   5.9
  9250  11.1  52.0  280   7  4   8.9   4.9 |  12.2  54.0  265   5  3   9.8   5.4
  9000  11.7  53.1  280   7  4   7.7   4.2 |  12.9  55.2  270   5  3   8.3   4.6
  8750  12.3  54.1  275   7  3   7.7   4.2 |  13.5  56.3  270   5  3   9.0   4.9
  8500  12.8  55.0  275   6  3   8.2   4.5 |  14.2  57.6  270   5  2   9.7   5.3
  8250  13.4  56.1  275   5  3   7.6   4.2 |  15.0  59.0  270   5  2   9.4   5.1
  8000  14.0  57.2  275   4  2   9.5   5.2 |  15.7  60.3  270   4  2  10.1   5.6
  7750  14.8  58.6  270   4  2   9.5   5.2 |  16.5  61.7  275   4  2  10.3   5.6
  7500  15.4  59.7  270   3  2   7.4   4.1 |  17.2  63.0  275   4  2   9.6   5.3
  7250  16.0  60.8  265   3  1   8.5   4.7 |  17.9  64.2  275   4  2  10.0   5.5
  7000  16.6  61.9  260   2  1   6.1   3.3 |  18.6  65.5  280   4  2   9.0   4.9
  6750  16.9  62.4  245   2  1   6.2   3.4 |  19.3  66.7  280   4  2   9.4   5.2
  6500  17.5  63.5  230   2  1   8.6   4.7 |  20.1  68.2  280   4  2  10.6   5.8
  6250  18.1  64.6  220   2  1   8.0   4.4 |  20.8  69.4  280   4  2  10.5   5.7
  6000  18.7  65.7  210   2  1   7.4   4.1 |  21.6  70.9  285   4  2  10.7   5.9
  5750  19.2  66.6  195   2  1  11.0   6.0 |  22.6  72.7  285   4  2  15.6   8.5
  5500  20.3  68.5  195   2  1  18.5  10.1 |  24.0  75.2  285   3  2  23.8  13.0

           05/25/2017 at 1500 MDT          |       05/25/2017 at 1800 MDT
                                           |
CAPE...  +614.7    LI...       -1.7        | CAPE...  +598.9    LI...       -1.7
CINH...    -9.6    K Index... +27.2        | CINH...   -38.6    K Index... +28.0
                                           |
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 -59.3 -74.7  250  19 10   1.7   0.9 | -58.9 -74.0  255  19 10   1.9   1.0
 45000 -56.8 -70.2  250  30 15   0.8   0.4 | -56.2 -69.2  255  27 14   0.2   0.1
 40000 -55.4 -67.7  245  31 16   0.9   0.5 | -55.7 -68.3  255  27 14   0.3   0.2
 38000 -54.1 -65.4  250  29 15   2.5   1.4 | -54.7 -66.5  255  24 12   2.3   1.3
 36000 -52.6 -62.7  250  25 13   2.5   1.4 | -53.3 -63.9  255  19 10   2.3   1.3
 34000 -50.2 -58.4  255  22 11   7.2   3.9 | -50.9 -59.6  255  16  8   8.0   4.4
 32000 -45.9 -50.6  255  18  9   7.2   3.9 | -46.1 -51.0  250  17  9   8.1   4.4
 30000 -41.3 -42.3  250  16  8   8.6   4.7 | -41.2 -42.2  250  18  9   8.5   4.7
 29000 -38.7 -37.7  250  16  8   8.6   4.7 | -38.0 -36.4  250  18  9   8.5   4.7
 28000 -36.1 -33.0  250  16  8   8.6   4.7 | -35.5 -31.9  250  18  9   8.5   4.7
 27000 -33.5 -28.3  250  16  8   8.3   4.5 | -33.0 -27.4  250  18  9   8.2   4.5
 26000 -31.1 -24.0  250  17  9   8.2   4.5 | -30.5 -22.9  250  18  9   8.2   4.5
 25000 -28.6 -19.5  255  17  9   8.3   4.5 | -28.1 -18.6  250  18  9   8.2   4.5
 24000 -26.2 -15.2  255  18  9   8.3   4.5 | -25.7 -14.3  255  18  9   8.0   4.4
 23000 -23.7 -10.7  255  18  9   8.3   4.6 | -23.3  -9.9  255  17  9   7.9   4.4
 22000 -21.2  -6.2  255  18  9   8.4   4.6 | -21.0  -5.8  250  17  9   8.0   4.4
 21000 -18.8  -1.8  250  19 10   8.0   4.4 | -18.6  -1.5  250  17  9   7.9   4.3
 20000 -15.9   3.4  250  18  9   8.0   4.4 | -16.3   2.7  255  16  8   7.9   4.4
 19500 -14.7   5.5  250  17  9   8.0   4.4 | -15.1   4.8  255  16  8   7.9   4.4
 19000 -13.5   7.7  250  17  9   8.0   4.4 | -14.0   6.8  255  15  8   8.0   4.4
 18500 -12.4   9.7  250  17  9   7.5   4.1 | -12.8   9.0  255  15  8   7.8   4.3
 18000 -11.3  11.7  245  16  8   7.6   4.2 | -11.7  10.9  255  14  7   7.7   4.2
 17500 -10.2  13.6  245  16  8   7.7   4.2 | -10.6  12.9  255  14  7   7.7   4.2
 17000  -9.0  15.8  245  15  8   7.8   4.3 |  -9.4  15.1  255  13  7   7.8   4.3
 16500  -7.9  17.8  245  15  8   7.7   4.3 |  -8.3  17.1  255  13  7   7.8   4.3
 16000  -6.7  19.9  245  14  7   8.5   4.7 |  -6.6  20.1  255  12  6   7.9   4.3
 15500  -5.4  22.3  245  14  7   8.4   4.6 |  -5.4  22.3  255  11  6   7.9   4.3
 15000  -4.1  24.6  240  13  7   8.9   4.9 |  -4.2  24.4  255  11  5   8.2   4.5
 14500  -2.8  27.0  240  12  6   9.0   4.9 |  -3.0  26.6  255  10  5   8.2   4.5
 14000  -1.5  29.3  240  12  6   9.1   5.0 |  -1.8  28.8  255   9  5   8.5   4.7
 13500  -0.1  31.8  240  11  5   9.2   5.1 |  -0.6  30.9  255   9  4   8.7   4.8
 13000   1.3  34.3  240  10  5   9.2   5.1 |   0.7  33.3  260   8  4   9.0   4.9
 12500   2.6  36.7  240   9  5   9.2   5.0 |   2.1  35.8  260   8  4   9.3   5.1
 12000   4.0  39.2  240   8  4   9.2   5.0 |   3.5  38.3  260   7  4   9.4   5.2
 11500   5.4  41.7  245   8  4   9.4   5.2 |   4.9  40.8  265   7  3   9.7   5.3
 11000   6.8  44.2  245   7  4   9.3   5.1 |   6.3  43.3  265   6  3   9.4   5.2
 10500   8.0  46.4  245   6  3   8.0   4.4 |   7.6  45.7  270   6  3   8.5   4.7
 10250   8.7  47.7  250   6  3  10.0   5.5 |   8.3  46.9  275   6  3  10.3   5.6
 10000   9.5  49.1  250   6  3  11.3   6.2 |   9.1  48.4  275   6  3  11.3   6.2
  9750  10.3  50.5  250   5  3  10.7   5.9 |   9.9  49.8  280   6  3  10.4   5.7
  9500  11.1  52.0  250   5  3  11.0   6.0 |  10.7  51.3  285   6  3  10.7   5.9
  9250  11.9  53.4  255   5  2  10.0   5.5 |  11.5  52.7  285   7  3   9.4   5.2
  9000  12.6  54.7  255   5  2   8.1   4.4 |  12.1  53.8  290   7  3   7.4   4.0
  8750  13.2  55.8  255   4  2   8.8   4.9 |  12.6  54.7  290   7  3   8.2   4.5
  8500  13.9  57.0  255   4  2   9.8   5.4 |  13.3  55.9  290   7  4   8.9   4.9
  8250  14.6  58.3  260   4  2   9.4   5.2 |  13.9  57.0  295   7  4   8.9   4.9
  8000  15.3  59.5  260   4  2  10.1   5.5 |  14.6  58.3  295   7  4   8.5   4.7
  7750  16.1  61.0  260   4  2  10.3   5.6 |  15.2  59.4  295   7  4   8.1   4.4
  7500  16.8  62.2  265   3  2   9.7   5.3 |  15.8  60.4  300   7  4   8.2   4.5
  7250  17.6  63.7  265   3  2  10.2   5.6 |  16.4  61.5  300   7  4   8.2   4.5
  7000  18.3  64.9  270   3  2   8.8   4.8 |  17.0  62.6  305   7  4   6.9   3.8
  6750  18.9  66.0  275   3  2   9.3   5.1 |  17.4  63.3  305   7  4   7.0   3.9
  6500  19.7  67.5  275   3  1  11.1   6.1 |  18.0  64.4  310   7  4   8.0   4.4
  6250  20.5  68.9  275   3  1  10.6   5.8 |  18.5  65.3  315   6  3   8.3   4.6
  6000  21.3  70.3  280   3  1  10.2   5.6 |  19.2  66.6  320   6  3  10.0   5.5
  5750  22.1  71.8  285   3  1  11.2   6.1 |  19.9  67.8  320   6  3  10.4   5.7
  5500  22.9  73.2  290   2  1  14.0   7.7 |  20.6  69.1  325   5  2   9.5   5.2
________________________________________________________________________________

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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