Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 151317
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0617 MST Sunday, January 15, 2017

This forecast is for Sunday, January 15, 2017:

If the trigger temperature of 51.5 F/10.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7361 ft MSL (2076 ft AGL)

Forecast maximum temperature................... 40.0 F/4.9 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................. 6196 ft MSL (911 ft AGL)
Thermal soaring outlook for Monday 01/16....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 14402 ft MSL (9117 ft AGL)
Wave soaring outlook for Monday 01/16.......... Poor

Remarks...

Sunrise/Sunset.................... 07:18:37 / 16:59:32 MST
Total possible sunshine........... 9 hr 40 min 55 sec (580 min 55 sec)
Altitude of sun at 12:09:04 MST... 29.22 degrees

Upper air data from rawinsonde observation taken on 01/15/2017 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 14580 ft MSL (9295 ft AGL)
Lifted condensation level....... 9377 ft MSL (4091 ft AGL)
Lifted index.................... +12.3
K index......................... +13.3

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  -62.5 -80.5   245   24   12   3.5   1.9   96.6 205.8    52.5      M    M
 45000  -57.2 -71.0   260   22   12   3.1   1.7   80.7 177.2    46.5      M    M
 40000  -58.7 -73.7   230   47   24 -20.4 -11.2   55.2 131.3    33.1      M    M
 38000  -61.9 -79.4   225   46   24  -0.0  -0.0   41.5 106.7    24.9      M    M
 36000  -61.0 -77.8   220   55   28   4.1   2.2   34.2  93.6    20.5      M    M
 34000  -57.7 -71.9   215   65   33   9.4   5.2   30.6  87.0    18.5      M    M
 32000  -51.3 -60.3   215   63   32   9.5   5.2   30.3  86.5    18.9      M    M
 30000  -45.7 -50.3   225   58   30   8.9   4.9   30.1  86.1    19.2      M    M
 29000  -43.0 -45.4   225   53   27   8.9   4.9   29.6  85.2    19.1      M    M
 28000  -40.4 -40.7   230   49   25   8.9   4.9   29.2  84.5    19.0      M    M
 27000  -37.7 -35.9   230   45   23   8.9   4.9   28.9  84.1    19.1      M    M
 26000  -35.1 -31.2   235   41   21   8.5   4.7   28.6  83.5    19.0      M    M
 25000  -32.6 -26.7   230   36   19   8.5   4.7   28.2  82.7    18.9      M    M
 24000  -30.1 -22.2   230   31   16   8.3   4.5   27.7  81.8    18.7      M    M
 23000  -27.7 -17.9   230   24   13   7.8   4.3   26.9  80.4    18.3      M    M
 22000  -25.4 -13.7   225   17    9   7.8   4.3   26.2  79.1    17.9      M    M
 21000  -23.0  -9.4   215   10    5   7.8   4.3   25.6  78.0    17.6      M    M
 20000  -20.5  -4.9   205   12    6   9.2   5.0   25.1  77.2    17.4      M    M
 19500  -19.1  -2.4   205   12    6  10.1   5.5   25.0  77.0    17.4      M    M
 19000  -18.6  -1.5   200   13    7  -2.3  -1.3   24.0  75.1    16.6      M    M
 18500  -18.5  -1.3   205   14    7   5.0   2.7   22.4  72.3    15.3      M    M
 18000  -17.4   0.7   210   13    7   6.8   3.7   21.9  71.4    15.0      M    M
 17500  -16.4   2.5   210   12    6   6.9   3.8   21.4  70.4    14.6      M    M
 17000  -15.3   4.5   215   11    6   7.0   3.8   20.9  69.6    14.3      M    M
 16500  -14.3   6.3   220   10    5   7.0   3.8   20.4  68.8    14.0      M    M
 16000  -12.8   9.0   225    9    5   6.6   3.6   19.7  67.5    13.4      M    M
 15500  -11.8  10.8   215   11    6   6.6   3.6   19.2  66.5    12.9      M    M
 15000  -10.9  12.4   210   13    7   6.7   3.7   18.6  65.6    12.5      M    M
 14500   -9.9  14.2   205   14    7   7.7   4.2   18.2  64.8    12.1      M    M
 14000   -8.7  16.3   205   16    8   8.0   4.4   17.9  64.3    11.9      M    M
 13500   -7.5  18.5   200   17    9   8.1   4.4   17.6  63.7    11.7      M    M
 13000   -6.3  20.7   200   18    9   8.1   4.4   17.3  63.2    11.4      M    M
 12500   -5.2  22.6   195   18    9   8.1   4.5   17.1  62.8    11.2      M    M
 12000   -4.0  24.8   195   19   10   8.5   4.6   16.9  62.3    11.1      M    M
 11500   -3.0  26.6   190   19   10   2.9   1.6   16.3  61.4    10.6      M    M
 11000   -2.8  27.0   190   19   10   1.9   1.0   15.1  59.1     9.4      M    M
 10500   -2.5  27.5   180   16    8   1.7   1.0   13.8  56.8     8.3      M    M
 10250   -2.4  27.7   175   15    8   2.2   1.2   13.2  55.7     7.7      M    M
 10000   -2.2  28.0   170   14    7   3.7   2.0   12.6  54.7     7.2      M    M
  9750   -1.9  28.6   170   13    7   4.3   2.4   12.2  53.9     6.8      M    M
  9500   -1.5  29.3   170   12    6   4.1   2.3   11.7  53.1     6.4      M    M
  9250   -1.2  29.8   170   11    6   4.2   2.3   11.3  52.3     6.0      M    M
  9000   -0.9  30.4   170   10    5   4.1   2.3   10.9  51.6     5.6      M    M
  8750   -0.6  30.9   170    8    4   4.4   2.4   10.4  50.8     5.2      M    M
  8500   -0.3  31.5   175    6    3   3.3   1.8   10.0  50.0     4.8      M    M
  8250   -0.4  31.3   175    4    2  -8.4  -4.6    9.2  48.5     4.0      M    M
  8000   -1.4  29.5   185    2    1 -16.4  -9.0    7.3  45.1     2.2      M    M
  7750   -2.2  28.0   200    1    1  -2.8  -1.5    5.7  42.2     0.7      M    M
  7500   -1.9  28.6   255    1    0   5.7   3.1    5.2  41.4     0.2      M    M
  7250   -1.6  29.1   310    1    1   3.3   1.8    4.8  40.6    -0.2    228  1.2
  7000   -1.3  29.7   325    2    1   4.4   2.4    4.3  39.8    -0.6    211  1.1
  6750   -1.0  30.2   330    3    1   2.4   1.3    3.9  39.0    -1.0    195  1.0
  6500   -1.0  30.2   335    3    2  -1.7  -0.9    3.1  37.7    -1.8    187  0.9
  6250   -1.2  29.8   340    4    2  -2.8  -1.6    2.2  36.0    -2.7    186  0.9
  6000   -1.4  29.5   340    5    3  -2.9  -1.6    1.3  34.3    -3.7    185  0.9
  5750   -1.7  28.9   340    3    2  -1.6  -0.9    0.3  32.6    -4.6    184  0.9
  5500   -1.9  28.6   340    2    1  -6.5  -3.6   -0.6  30.9    -5.6    183  0.9

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

           01/15/2017 at 0800 MST          |       01/15/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +1.7        | CAPE...     0.0    LI...       +1.6
CINH...     0.0    K Index... +18.3        | CINH...    -0.3    K Index... +21.2
                                           |
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 -60.0 -76.0  260  11  6   1.9   1.0 | -60.7 -77.3  260  11  6   2.5   1.4
 45000 -57.0 -70.6  245  11  6   1.7   0.9 | -56.7 -70.1  245  13  7   2.2   1.2
 40000 -60.3 -76.5  225  18  9  -2.3  -1.3 | -59.5 -75.1  220  19 10  -2.0  -1.1
 38000 -60.5 -76.9  220  22 12   2.5   1.4 | -59.7 -75.5  210  23 12   2.3   1.3
 36000 -59.1 -74.4  210  29 15   2.5   1.4 | -58.3 -72.9  200  31 16   2.3   1.3
 34000 -57.3 -71.1  210  35 18   7.6   4.2 | -56.6 -69.9  195  38 19   7.6   4.2
 32000 -51.5 -60.7  210  32 16   8.6   4.7 | -51.0 -59.8  200  29 15   8.4   4.6
 30000 -46.3 -51.3  210  28 15   9.2   5.1 | -45.8 -50.4  205  22 11   9.2   5.0
 29000 -43.5 -46.3  210  26 13   9.3   5.1 | -43.0 -45.4  205  20 10   9.3   5.1
 28000 -40.8 -41.4  210  23 12   9.3   5.1 | -40.2 -40.4  200  18  9   9.3   5.1
 27000 -38.0 -36.4  210  20 10   8.9   4.9 | -37.5 -35.5  200  17  9   8.8   4.8
 26000 -35.4 -31.7  210  18  9   8.6   4.7 | -35.0 -31.0  200  16  8   8.4   4.6
 25000 -32.8 -27.0  210  16  8   8.6   4.7 | -32.5 -26.5  200  15  8   8.4   4.6
 24000 -30.3 -22.5  210  13  7   8.4   4.6 | -29.9 -21.8  205  14  7   8.4   4.6
 23000 -27.9 -18.2  205  11  6   7.8   4.3 | -27.4 -17.3  205  13  7   8.7   4.8
 22000 -25.6 -14.1  205   9  5   7.8   4.3 | -24.8 -12.6  200  12  6   8.7   4.8
 21000 -23.3  -9.9  205   8  4   7.7   4.2 | -22.2  -8.0  200  10  5   7.3   4.0
 20000 -21.0  -5.8  205   7  4   7.6   4.2 | -20.3  -4.5  195   8  4   6.4   3.5
 19500 -19.9  -3.8  200   6  3   7.6   4.2 | -19.4  -2.9  185   7  4   6.4   3.5
 19000 -18.8  -1.8  200   6  3   7.6   4.2 | -18.5  -1.3  180   6  3   6.4   3.5
 18500 -17.6   0.3  200   6  3   8.1   4.4 | -17.5   0.5  170   5  3   6.7   3.7
 18000 -16.3   2.7  200   6  3   8.7   4.8 | -16.4   2.5  165   5  2   7.4   4.0
 17500 -15.0   5.0  200   6  3   8.9   4.9 | -15.3   4.5  165   4  2   7.3   4.0
 17000 -13.9   7.0  200   6  3   7.0   3.9 | -14.2   6.4  170   4  2   7.5   4.1
 16500 -12.8   9.0  205   6  3   7.2   4.0 | -12.6   9.3  170   4  2   7.6   4.2
 16000 -11.3  11.7  205   6  3   6.6   3.6 | -11.5  11.3  170   4  2   6.7   3.7
 15500 -10.3  13.5  205   6  3   6.7   3.7 | -10.6  12.9  170   4  2   6.8   3.7
 15000  -9.4  15.1  205   6  3   6.2   3.4 |  -9.6  14.7  165   4  2   6.4   3.5
 14500  -8.5  16.7  205   6  3   6.3   3.4 |  -8.7  16.3  160   4  2   6.3   3.5
 14000  -7.6  18.3  205   5  3   5.5   3.0 |  -7.8  18.0  155   4  2   5.6   3.1
 13500  -6.9  19.6  205   5  3   5.3   2.9 |  -7.1  19.2  150   4  2   5.1   2.8
 13000  -6.1  21.0  200   4  2   4.6   2.5 |  -6.3  20.7  150   4  2   4.0   2.2
 12500  -5.6  21.9  195   4  2   4.1   2.3 |  -5.9  21.4  150   4  2   3.0   1.6
 12000  -5.0  23.0  185   4  2   4.6   2.5 |  -5.5  22.1  155   4  2   4.5   2.5
 11500  -4.3  24.3  180   4  2   5.0   2.7 |  -4.6  23.7  150   4  2   6.9   3.8
 11000  -3.6  25.5  175   5  2   4.7   2.6 |  -3.6  25.5  150   4  2   6.2   3.4
 10500  -2.9  26.8  165   4  2   4.4   2.4 |  -2.8  27.0  125   4  2   5.1   2.8
 10250  -2.6  27.3  160   4  2   4.3   2.4 |  -2.4  27.7  110   4  2   6.0   3.3
 10000  -2.4  27.7  155   4  2   1.2   0.6 |  -2.1  28.2  100   4  2   1.0   0.6
  9750  -2.4  27.7  150   4  2  -0.9  -0.5 |  -2.3  27.9  100   4  2  -4.5  -2.4
  9500  -2.4  27.7  145   3  2  -0.2  -0.1 |  -2.6  27.3  090   4  2  -3.9  -2.2
  9250  -2.4  27.7  140   3  2  -0.2  -0.1 |  -2.8  27.0  085   4  2  -3.9  -2.1
  9000  -2.4  27.7  130   3  1   0.3   0.2 |  -3.1  26.4  080   4  2  -2.9  -1.6
  8750  -2.3  27.9  120   3  1  -0.6  -0.3 |  -3.2  26.2  070   3  2  -1.8  -1.0
  8500  -2.4  27.7  105   3  1  -1.8  -1.0 |  -3.3  26.1  060   3  2  -2.1  -1.1
  8250  -2.4  27.7  095   3  1  -0.5  -0.3 |  -3.4  25.9  050   3  2  -0.3  -0.2
  8000  -2.4  27.7  080   3  1   0.2   0.1 |  -3.3  26.1  035   3  2   2.2   1.2
  7750  -2.4  27.7  070   3  1   0.9   0.5 |  -3.1  26.4  030   3  2   2.1   1.1
  7500  -2.3  27.9  065   3  1   1.7   0.9 |  -3.0  26.6  020   3  2   2.1   1.2
  7250  -2.2  28.0  055   3  1   1.1   0.6 |  -2.8  27.0  010   3  2   2.9   1.6
  7000  -2.1  28.2  050   3  1   0.7   0.4 |  -2.5  27.5  005   3  2   3.6   2.0
  6750  -2.1  28.2  040   2  1   1.6   0.9 |  -2.3  27.9  355   3  2   2.8   1.5
  6500  -2.0  28.4  030   2  1  -0.2  -0.1 |  -2.1  28.2  350   3  2   2.2   1.2
  6250  -2.1  28.2  020   2  1  -2.3  -1.3 |  -1.9  28.6  345   3  1   2.5   1.4
  6000  -2.3  27.9  360   1  1  -1.5  -0.8 |  -1.8  28.8  340   2  1   2.1   1.2
  5750  -2.4  27.7  330   1  1  -2.5  -1.4 |  -1.6  29.1  330   2  1   3.4   1.9
  5500  -2.7  27.1  300   1  0  -5.0  -2.7 |  -1.2  29.8  325   1  1   8.8   4.8

           01/15/2017 at 1400 MST          |       01/15/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +2.0        | CAPE...     0.0    LI...       +2.5
CINH...    -0.9    K Index... +22.3        | CINH...    -0.4    K Index... +22.0
                                           |
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 -60.4 -76.7  265  11  6   2.9   1.6 | -59.7 -75.5  265  12  6   2.8   1.6
 45000 -55.9 -68.6  255  13  7   2.7   1.5 | -55.5 -67.9  260  12  6   3.0   1.6
 40000 -60.5 -76.9  225  20 10  -3.3  -1.8 | -59.3 -74.7  230  15  7  -2.8  -1.5
 38000 -60.9 -77.6  215  23 12   3.8   2.1 | -59.9 -75.8  210  17  9   2.1   1.2
 36000 -58.6 -73.5  195  28 14   3.8   2.1 | -58.6 -73.5  185  22 11   2.1   1.2
 34000 -56.1 -69.0  185  34 17   7.6   4.2 | -57.1 -70.8  175  29 15   7.7   4.2
 32000 -50.5 -58.9  195  27 14   8.4   4.6 | -50.7 -59.3  180  25 13   9.5   5.2
 30000 -45.4 -49.7  200  21 11   8.8   4.8 | -45.0 -49.0  185  21 11   9.2   5.1
 29000 -42.7 -44.9  200  19 10   8.8   4.8 | -42.2 -44.0  190  18  9   9.3   5.1
 28000 -40.1 -40.2  200  17  9   8.8   4.9 | -39.4 -38.9  195  15  8   9.3   5.1
 27000 -37.4 -35.3  195  15  8   9.1   5.0 | -36.7 -34.1  205  12  6   9.0   5.0
 26000 -34.6 -30.3  195  14  7   9.4   5.1 | -34.1 -29.4  200  11  6   8.5   4.7
 25000 -31.8 -25.2  190  13  7   9.4   5.1 | -31.6 -24.9  200  10  5   8.5   4.7
 24000 -29.0 -20.2  190  12  6   9.2   5.1 | -29.0 -20.2  195   9  5   8.6   4.7
 23000 -26.7 -16.1  185  10  5   7.5   4.1 | -26.7 -16.1  195   8  4   7.6   4.2
 22000 -24.5 -12.1  180   9  4   7.6   4.1 | -24.4 -11.9  195   7  3   7.7   4.2
 21000 -22.2  -8.0  175   7  3   7.4   4.0 | -22.1  -7.8  190   6  3   7.4   4.1
 20000 -20.1  -4.2  175   5  3   7.2   3.9 | -20.1  -4.2  175   4  2   7.0   3.9
 19500 -19.0  -2.2  170   5  2   7.2   4.0 | -19.0  -2.2  165   4  2   7.0   3.9
 19000 -18.0  -0.4  170   4  2   7.2   3.9 | -18.0  -0.4  150   3  2   7.0   3.9
 18500 -16.9   1.6  170   3  2   7.1   3.9 | -16.9   1.6  130   3  2   7.1   3.9
 18000 -15.9   3.4  160   3  2   6.5   3.6 | -15.9   3.4  120   3  2   7.2   3.9
 17500 -15.0   5.0  150   3  2   6.6   3.6 | -14.8   5.4  110   4  2   7.2   4.0
 17000 -14.0   6.8  145   3  2   6.5   3.6 | -13.8   7.2  105   4  2   6.8   3.7
 16500 -13.0   8.6  140   3  2   6.6   3.6 | -12.8   9.0  100   4  2   6.7   3.7
 16000 -11.6  11.1  135   3  2   6.8   3.7 | -11.4  11.5  095   5  3   6.0   3.3
 15500 -10.6  12.9  135   3  2   6.9   3.8 | -10.5  13.1  095   5  3   6.0   3.3
 15000  -9.6  14.7  135   4  2   6.1   3.4 |  -9.7  14.5  095   6  3   6.0   3.3
 14500  -8.8  16.2  135   4  2   5.9   3.2 |  -8.8  16.2  095   6  3   6.0   3.3
 14000  -7.9  17.8  135   4  2   5.6   3.1 |  -7.9  17.8  100   7  4   5.5   3.0
 13500  -7.2  19.0  130   4  2   5.3   2.9 |  -7.2  19.0  095   7  4   4.6   2.5
 13000  -6.4  20.5  125   5  2   4.8   2.6 |  -6.6  20.1  095   8  4   4.3   2.4
 12500  -5.8  21.6  115   4  2   3.8   2.1 |  -6.1  21.0  090   7  4   3.2   1.8
 12000  -5.3  22.5  105   4  2   4.7   2.6 |  -5.6  21.9  085   7  4   3.8   2.1
 11500  -4.4  24.1  095   5  3   7.0   3.8 |  -4.8  23.4  080   7  3   6.7   3.7
 11000  -3.3  26.1  090   6  3   6.3   3.4 |  -3.8  25.2  075   7  3   6.3   3.5
 10500  -2.6  27.3  090   7  3   4.5   2.4 |  -3.0  26.6  080   6  3   5.4   2.9
 10250  -2.3  27.9  090   7  4   5.6   3.1 |  -2.6  27.3  080   6  3   6.3   3.4
 10000  -1.9  28.6  090   8  4   1.6   0.9 |  -2.2  28.0  085   6  3   3.1   1.7
  9750  -2.1  28.2  090   7  4  -4.0  -2.2 |  -2.1  28.2  080   6  3  -0.3  -0.2
  9500  -2.4  27.7  090   7  3  -4.2  -2.3 |  -2.1  28.2  080   5  3  -0.1  -0.0
  9250  -2.6  27.3  085   6  3  -3.9  -2.1 |  -2.1  28.2  080   5  3   1.1   0.6
  9000  -3.0  26.6  085   5  3  -5.8  -3.2 |  -2.1  28.2  080   5  2  -3.7  -2.0
  8750  -3.4  25.9  075   4  2  -3.8  -2.1 |  -2.6  27.3  070   4  2  -6.5  -3.6
  8500  -3.4  25.9  060   3  2  -1.0  -0.6 |  -2.9  26.8  050   3  2  -3.9  -2.2
  8250  -3.5  25.7  040   3  2  -0.9  -0.5 |  -3.2  26.2  025   3  2  -4.0  -2.2
  8000  -3.5  25.7  025   3  2   1.8   1.0 |  -3.4  25.9  010   3  2  -0.8  -0.5
  7750  -3.3  26.1  010   3  2   1.6   0.9 |  -3.3  26.1  005   4  2   1.0   0.5
  7500  -3.3  26.1  005   3  2   0.4   0.2 |  -3.3  26.1  005   4  2   0.6   0.4
  7250  -3.2  26.2  360   3  2   2.4   1.3 |  -3.2  26.2  360   4  2   1.4   0.8
  7000  -2.9  26.8  355   3  2   4.0   2.2 |  -3.0  26.6  360   3  2   2.4   1.3
  6750  -2.6  27.3  350   3  2   3.5   1.9 |  -2.9  26.8  360   3  2   1.4   0.8
  6500  -2.3  27.9  345   3  2   4.3   2.3 |  -2.8  27.0  360   3  1   2.1   1.2
  6250  -2.0  28.4  345   3  1   5.1   2.8 |  -2.5  27.5  355   2  1   5.0   2.8
  6000  -1.6  29.1  345   2  1   4.8   2.6 |  -2.1  28.2  350   2  1   5.6   3.1
  5750  -1.2  29.8  340   2  1   6.2   3.4 |  -1.7  28.9  340   2  1   6.0   3.3
  5500  -0.6  30.9  335   1  1  11.3   6.2 |  -1.1  30.0  330   1  1   9.3   5.1
________________________________________________________________________________

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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