Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 151232
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0532 MST Monday, January 15, 2018

This forecast is for Monday, January 15, 2018:

If the trigger temperature of 52.7 F/11.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 197 ft/min (1.0 m/s)
   Maximum height of thermals.................. 7496 ft MSL (2657 ft AGL)

Forecast maximum temperature................... 47.0 F/8.8 C
Time of trigger temperature.................... None
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................. 6424 ft MSL (1585 ft AGL)
Thermal soaring outlook for Tuesday 01/16...... Fair

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 07:31:32 / 17:14:52 MST
Total possible sunshine........... 9 hr 43 min 20 sec (583 min 20 sec)
Altitude of sun at 12:23:35 MST... 29.92 degrees

Upper air data from rawinsonde observation taken on 01/15/2018 at 0500 MST

Freezing level.................. 5462 ft MSL (623 ft AGL)
Additional freezing level....... 8183 ft MSL (3344 ft AGL)
Convective condensation level... 17161 ft MSL (12322 ft AGL)
Lifted condensation level....... 11099 ft MSL (6260 ft AGL)
Lifted index.................... +12.0
K index......................... -3.1

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  -63.6 -82.5   295   54   28  -9.2  -5.1   96.8 206.3    50.1      M    M
 45000  -62.2 -80.0   310   63   32   1.8   1.0   74.4 166.0    40.1      M    M
 40000  -66.7 -88.1   305   51   26   2.6   1.4   43.9 110.9    23.1      M    M
 38000  -63.3 -81.9   305   47   24   6.8   3.7   40.1 104.2    21.3      M    M
 36000  -58.7 -73.7   310   44   22   8.1   4.5   38.2 100.7    20.6      M    M
 34000  -53.2 -63.8   315   39   20   7.9   4.3   36.7  98.0    20.1      M    M
 32000  -48.5 -55.3   320   39   20   8.0   4.4   35.1  95.2    19.5      M    M
 30000  -43.5 -46.3   320   43   22   8.5   4.6   34.0  93.2    19.2      M    M
 29000  -41.0 -41.8   320   42   22   8.4   4.6   33.4  92.2    19.0      M    M
 28000  -38.6 -37.5   315   41   21   8.1   4.4   32.8  91.1    18.8      M    M
 27000  -36.1 -33.0   315   40   21   8.2   4.5   32.2  89.9    18.5      M    M
 26000  -34.1 -29.4   310   39   20   7.5   4.1   31.1  87.9    17.8      M    M
 25000  -31.7 -25.1   310   38   20   8.5   4.7   30.5  86.9    17.6      M    M
 24000  -29.0 -20.2   310   36   19   8.6   4.7   30.1  86.2    17.5      M    M
 23000  -26.5 -15.7   310   36   19   7.5   4.1   29.6  85.3    17.3      M    M
 22000  -24.2 -11.6   315   36   19   9.0   5.0   28.9  84.0    16.9      M    M
 21000  -21.5  -6.7   315   36   19   8.9   4.9   28.5  83.4    16.8      M    M
 20000  -19.0  -2.2   315   36   19   7.7   4.2   28.1  82.6    16.6      M    M
 19500  -17.8  -0.0   315   36   18   7.8   4.3   27.8  82.0    16.4      M    M
 19000  -16.6   2.1   315   35   18   7.8   4.3   27.4  81.3    16.2      M    M
 18500  -15.0   5.0   310   34   18   6.4   3.5   26.7  80.1    15.7      M    M
 18000  -14.3   6.3   310   34   17   4.4   2.4   26.0  78.7    15.1      M    M
 17500  -13.6   7.5   310   32   16   5.5   3.0   25.1  77.2    14.4      M    M
 17000  -12.8   9.0   310   30   16   5.5   3.0   24.4  75.9    13.9      M    M
 16500  -11.9  10.6   310   28   15   5.2   2.9   23.7  74.6    13.3      M    M
 16000  -10.9  12.4   310   27   14   8.0   4.4   23.2  73.7    12.9      M    M
 15500   -9.8  14.4   310   27   14   7.8   4.3   22.8  73.0    12.7      M    M
 15000   -8.6  16.5   310   26   14   7.8   4.3   22.5  72.4    12.5      M    M
 14500   -7.4  18.7   310   26   13   8.1   4.4   22.2  71.9    12.3      M    M
 14000   -6.6  20.1   310   26   13   3.9   2.1   21.5  70.7    11.7      M    M
 13500   -6.1  21.0   310   24   12   3.5   1.9   20.6  69.0    10.9      M    M
 13000   -5.3  22.5   315   22   11   8.3   4.6   19.7  67.5    10.3      M    M
 12500   -4.1  24.6   315   21   11   5.9   3.2   19.5  67.0    10.0      M    M
 12000   -3.1  26.4   320   19   10   5.8   3.2   18.9  66.0     9.6      M    M
 11500   -2.2  28.0   320   17    9   5.9   3.3   18.2  64.8     9.1      M    M
 11000   -1.3  29.7   320   15    8   6.3   3.4   17.6  63.7     8.6      M    M
 10500   -0.6  30.9   315   13    7   2.0   1.1   16.8  62.3     7.8      M    M
 10250   -0.5  31.1   315   12    6   1.9   1.1   16.2  61.1     7.2      M    M
 10000   -0.4  31.3   310   12    6   2.3   1.3   15.6  60.0     6.7      M    M
  9750   -0.2  31.6   305   11    6   2.8   1.5   15.0  59.0     6.1      M    M
  9500   -0.1  31.8   295   11    6   1.0   0.6   14.4  57.9     5.5      M    M
  9250   -0.2  31.6   290   11    6  -3.5  -1.9   13.5  56.4     4.7      M    M
  9000   -0.6  30.9   280   11    6  -2.7  -1.5   12.5  54.4     3.6      M    M
  8750   -0.6  30.9   280   10    5   2.1   1.2   11.7  53.1     2.8      M    M
  8500   -0.4  31.3   275    9    4   3.9   2.1   11.2  52.1     2.3      M    M
  8250   -0.1  31.8   275    7    4   3.9   2.2   10.7  51.3     1.9      M    M
  8000    0.2  32.4   270    6    3   5.3   2.9   10.3  50.6     1.5      M    M
  7750    0.5  32.9   265    4    2   1.6   0.9    9.9  49.8     1.1      M    M
  7500    0.4  32.7   230    2    1  -3.8  -2.1    9.0  48.2     0.2      M    M
  7250    0.1  32.2   135    2    1  -2.0  -1.1    8.0  46.4    -0.8    198  1.0
  7000    0.1  32.2   115    4    2   1.6   0.9    7.3  45.1    -1.5    191  1.0
  6750    0.3  32.5   120    6    3   2.4   1.3    6.7  44.0    -2.1    178  0.9
  6500    0.4  32.7   125    7    4   2.3   1.3    6.1  43.0    -2.7    166  0.8
  6250    0.6  33.1   130    8    4   2.0   1.1    5.5  41.9    -3.2    153  0.8
  6000    0.8  33.4   135   10    5   3.3   1.8    5.0  40.9    -3.8    141  0.7
  5750    0.9  33.6   135    9    5  -1.6  -0.9    4.4  39.9    -4.4    129  0.7
  5500    0.4  32.7   130    8    4 -10.7  -5.9    3.1  37.6    -5.6    137  0.7
  5250   -0.5  31.1   125    6    3 -12.6  -6.9    1.5  34.7    -7.3    156  0.8
  5000   -1.4  29.5   110    5    2 -13.1  -7.2   -0.2  31.7    -9.0    177  0.9

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

           01/15/2018 at 0800 MST          |       01/15/2018 at 1100 MST
                                           |
K index... +6.1  LI... +5.9                | K index... +1.0  LI... +6.6
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -63.5 -82.3  315  47 24   1.0   0.5 | -62.7 -80.9  315  45 23   0.2   0.1
 45000 -62.0 -79.6  315  50 26   1.2   0.7 | -62.4 -80.3  310  49 25  -0.1  -0.0
 40000 -64.4 -83.9  315  47 24  -1.7  -0.9 | -64.0 -83.2  310  52 27  -1.1  -0.6
 38000 -62.7 -80.9  315  44 23   6.7   3.7 | -62.4 -80.3  310  49 25   6.2   3.4
 36000 -58.7 -73.7  315  40 21   6.7   3.7 | -58.7 -73.7  315  43 22   6.2   3.4
 34000 -54.4 -65.9  320  37 19   8.1   4.4 | -54.8 -66.6  320  38 20   8.1   4.5
 32000 -49.6 -57.3  320  35 18   8.1   4.4 | -50.0 -58.0  315  39 20   8.0   4.4
 30000 -44.7 -48.5  320  35 18   8.2   4.5 | -44.5 -48.1  320  39 20   8.3   4.6
 29000 -42.2 -44.0  320  35 18   8.2   4.5 | -42.0 -43.6  320  39 20   8.3   4.5
 28000 -39.8 -39.6  320  36 19   8.2   4.5 | -39.6 -39.3  325  39 20   8.3   4.5
 27000 -37.3 -35.1  325  37 19   8.4   4.6 | -37.1 -34.8  325  39 20   8.7   4.7
 26000 -34.8 -30.6  325  37 19   8.5   4.7 | -34.5 -30.1  325  39 20   8.7   4.8
 25000 -32.2 -26.0  325  38 19   8.5   4.7 | -31.9 -25.4  330  40 20   8.7   4.8
 24000 -29.7 -21.5  325  38 20   8.4   4.6 | -29.3 -20.7  330  40 20   8.5   4.7
 23000 -27.2 -17.0  325  38 20   8.2   4.5 | -26.8 -16.2  330  39 20   8.4   4.6
 22000 -24.1 -11.4  325  39 20   8.2   4.5 | -24.2 -11.6  330  39 20   8.5   4.6
 21000 -21.7  -7.1  325  38 20   7.9   4.3 | -21.8  -7.2  330  39 20   6.8   3.7
 20000 -19.3  -2.7  325  38 19   7.9   4.3 | -19.8  -3.6  330  38 19   6.8   3.8
 19500 -18.1  -0.6  325  37 19   7.9   4.3 | -18.8  -1.8  330  37 19   6.9   3.8
 19000 -16.9   1.6  325  37 19   7.9   4.3 | -17.7   0.1  330  37 19   6.9   3.8
 18500 -15.9   3.4  325  36 18   6.3   3.4 | -16.8   1.8  330  36 18   5.7   3.1
 18000 -14.9   5.2  325  35 18   6.4   3.5 | -15.6   3.9  330  34 18   5.4   2.9
 17500 -14.0   6.8  325  34 18   6.3   3.4 | -14.8   5.4  330  34 17   5.9   3.2
 17000 -13.1   8.4  325  33 17   6.2   3.4 | -13.9   7.0  335  33 17   6.0   3.3
 16500 -12.2  10.0  325  32 16   6.2   3.4 | -13.0   8.6  335  32 16   6.0   3.3
 16000 -11.3  11.7  330  31 16   6.0   3.3 | -12.1  10.2  335  31 16   6.1   3.3
 15500 -10.4  13.3  330  29 15   6.1   3.3 | -11.2  11.8  335  30 15   6.1   3.3
 15000  -9.6  14.7  330  28 14   5.1   2.8 | -10.3  13.5  340  29 15   6.0   3.3
 14500  -8.8  16.2  330  27 14   5.3   2.9 |  -9.4  15.1  340  28 15   6.1   3.3
 14000  -8.1  17.4  330  25 13   4.5   2.4 |  -8.6  16.5  340  27 14   5.3   2.9
 13500  -7.4  18.7  335  24 12   4.4   2.4 |  -7.8  18.0  340  26 14   5.3   2.9
 13000  -6.8  19.8  335  22 11   4.4   2.4 |  -7.0  19.4  345  25 13   5.5   3.0
 12500  -6.2  20.8  340  21 11   4.4   2.4 |  -6.2  20.8  345  24 12   5.5   3.0
 12000  -5.6  21.9  345  19 10   4.8   2.6 |  -5.5  22.1  350  23 12   5.3   2.9
 11500  -4.9  23.2  350  18  9   4.9   2.7 |  -4.7  23.5  355  22 11   5.4   2.9
 11000  -4.2  24.4  355  17  9   4.9   2.7 |  -3.9  25.0  360  21 11   4.7   2.6
 10500  -3.4  25.9  360  16  8   5.1   2.8 |  -3.3  26.1  005  19 10   4.9   2.7
 10250  -3.1  26.4  005  16  8   4.0   2.2 |  -2.9  26.8  005  19 10   3.3   1.8
 10000  -2.8  27.0  005  15  8   3.2   1.8 |  -2.8  27.0  005  18  9   2.1   1.2
  9750  -2.5  27.5  010  14  7   4.7   2.6 |  -2.6  27.3  005  17  9   3.3   1.8
  9500  -2.1  28.2  010  13  7   5.4   2.9 |  -2.4  27.7  010  15  8   3.6   1.9
  9250  -1.8  28.8  015  12  6   4.6   2.5 |  -2.1  28.2  010  14  7   3.3   1.8
  9000  -1.4  29.5  020  11  6   4.0   2.2 |  -1.9  28.6  015  12  6   3.2   1.8
  8750  -1.1  30.0  020  10  5   4.1   2.2 |  -1.6  29.1  015  11  6   4.1   2.3
  8500  -0.9  30.4  025   9  4   4.0   2.2 |  -1.3  29.7  020  10  5   4.5   2.5
  8250  -0.6  30.9  030   8  4   3.7   2.0 |  -1.0  30.2  025   9  4   4.2   2.3
  8000  -0.3  31.5  035   7  3   3.5   1.9 |  -0.7  30.7  030   8  4   3.8   2.1
  7750  -0.1  31.8  040   6  3   3.6   1.9 |  -0.4  31.3  035   7  4   5.0   2.7
  7500   0.2  32.4  050   5  3   3.6   2.0 |   0.0  32.0  040   7  3   5.0   2.8
  7250   0.5  32.9  055   5  2   3.5   1.9 |   0.3  32.5  045   6  3   3.9   2.1
  7000   0.7  33.3  065   5  2   3.6   2.0 |   0.6  33.1  050   6  3   3.9   2.1
  6750   1.0  33.8  070   4  2   3.2   1.8 |   0.9  33.6  055   6  3   4.4   2.4
  6500   1.2  34.2  075   4  2   1.1   0.6 |   1.3  34.3  055   5  3   5.6   3.1
  6250   1.2  34.2  085   5  2   0.0   0.0 |   1.7  35.1  060   4  2   6.2   3.4
  6000   1.3  34.3  095   5  3   0.2   0.1 |   2.2  36.0  065   3  2   5.3   2.9
  5750   1.0  33.8  095   6  3 -12.5  -6.9 |   2.7  36.9  070   3  2  10.1   5.6
  5500  -0.8  30.6  095   5  3 -32.2 -17.6 |   3.8  38.8  065   3  2  20.4  11.2
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/15/2018 at 1400 MST          |       01/15/2018 at 1700 MST
                                           |
K index... +3.0  LI... +6.0                | K index... -8.6  LI... +6.9
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -61.8 -79.2  315  43 22   0.5   0.3 | -62.3 -80.1  320  40 21   0.3   0.2
 45000 -61.1 -78.0  315  45 23   0.6   0.3 | -61.9 -79.4  315  47 24   0.4   0.2
 40000 -64.1 -83.4  315  57 29  -2.0  -1.1 | -64.5 -84.1  320  55 29  -1.9  -1.0
 38000 -62.6 -80.7  315  55 28   6.3   3.5 | -63.0 -81.4  320  56 29   6.6   3.6
 36000 -58.8 -73.8  315  49 25   6.3   3.5 | -59.0 -74.2  325  52 27   6.6   3.6
 34000 -54.8 -66.6  315  43 22   8.0   4.4 | -54.9 -66.8  325  49 25   8.1   4.4
 32000 -50.0 -58.0  320  43 22   8.0   4.4 | -50.0 -58.0  325  47 24   8.1   4.4
 30000 -45.2 -49.4  320  42 21   8.4   4.6 | -45.1 -49.2  325  46 24   8.3   4.5
 29000 -42.7 -44.9  320  41 21   8.4   4.6 | -42.6 -44.7  325  45 23   8.3   4.5
 28000 -40.1 -40.2  325  40 20   8.4   4.6 | -40.1 -40.2  325  44 23   8.3   4.5
 27000 -37.6 -35.7  325  39 20   8.5   4.7 | -37.7 -35.9  325  43 22   8.3   4.6
 26000 -35.0 -31.0  330  38 20   8.6   4.7 | -35.2 -31.4  325  42 21   8.4   4.6
 25000 -32.5 -26.5  330  38 19   8.6   4.7 | -32.7 -26.9  325  40 21   8.4   4.6
 24000 -29.9 -21.8  330  37 19   8.5   4.6 | -30.1 -22.2  325  39 20   8.3   4.6
 23000 -26.8 -16.2  330  37 19   8.2   4.5 | -27.7 -17.9  325  38 20   8.2   4.5
 22000 -24.3 -11.7  330  38 19   8.2   4.5 | -25.2 -13.4  330  38 19   8.2   4.5
 21000 -22.0  -7.6  330  38 19   6.8   3.7 | -22.3  -8.1  330  37 19   6.9   3.8
 20000 -19.9  -3.8  335  37 19   6.9   3.8 | -20.2  -4.4  330  35 18   7.0   3.8
 19500 -18.9  -2.0  335  36 19   6.9   3.8 | -19.1  -2.4  335  34 18   7.0   3.8
 19000 -17.8  -0.0  335  36 18   7.0   3.8 | -18.1  -0.6  335  33 17   7.1   3.9
 18500 -16.9   1.6  335  35 18   6.1   3.3 | -17.1   1.2  335  32 17   5.7   3.1
 18000 -15.9   3.4  335  34 18   6.2   3.4 | -16.2   2.8  335  31 16   5.8   3.2
 17500 -15.0   5.0  335  33 17   6.0   3.3 | -15.3   4.5  335  30 16   6.1   3.3
 17000 -14.1   6.6  335  32 17   5.9   3.2 | -14.4   6.1  335  30 15   6.2   3.4
 16500 -13.2   8.2  335  31 16   5.9   3.2 | -13.5   7.7  335  29 15   6.2   3.4
 16000 -12.4   9.7  335  31 16   5.5   3.0 | -12.6   9.3  335  29 15   5.5   3.0
 15500 -11.6  11.1  335  30 15   5.5   3.0 | -11.8  10.8  335  28 14   5.6   3.1
 15000 -10.8  12.6  335  29 15   5.7   3.1 | -11.1  12.0  335  28 14   4.5   2.5
 14500  -9.9  14.2  335  28 14   5.7   3.1 | -10.4  13.3  335  27 14   4.6   2.5
 14000  -9.1  15.6  335  27 14   5.0   2.8 |  -9.7  14.5  335  26 14   4.4   2.4
 13500  -8.4  16.9  335  26 13   5.0   2.7 |  -9.1  15.6  335  25 13   4.4   2.4
 13000  -7.7  18.1  340  25 13   5.2   2.8 |  -8.5  16.7  340  24 13   4.8   2.6
 12500  -7.0  19.4  340  24 12   5.2   2.9 |  -7.8  18.0  340  23 12   4.9   2.7
 12000  -6.2  20.8  345  23 12   5.3   2.9 |  -7.1  19.2  345  23 12   5.2   2.8
 11500  -5.4  22.3  350  22 11   5.3   2.9 |  -6.4  20.5  350  22 11   5.3   2.9
 11000  -4.7  23.5  355  21 11   4.9   2.7 |  -5.6  21.9  355  21 11   4.2   2.3
 10500  -4.0  24.8  005  20 10   5.0   2.7 |  -5.1  22.8  005  20 10   4.0   2.2
 10250  -3.6  25.5  005  19 10   3.8   2.1 |  -4.8  23.4  010  20 10   2.9   1.6
 10000  -3.4  25.9  010  19 10   2.3   1.3 |  -4.7  23.5  010  20 10   1.8   1.0
  9750  -3.3  26.1  010  17  9   2.9   1.6 |  -4.5  23.9  015  18  9   2.8   1.6
  9500  -3.0  26.6  015  15  8   3.3   1.8 |  -4.3  24.3  015  17  9   3.0   1.6
  9250  -2.8  27.0  020  13  7   3.1   1.7 |  -4.1  24.6  020  15  8   4.0   2.2
  9000  -2.6  27.3  025  12  6   3.2   1.8 |  -3.7  25.3  025  14  7   5.6   3.1
  8750  -2.3  27.9  030  11  6   4.3   2.4 |  -3.3  26.1  030  14  7   6.4   3.5
  8500  -1.9  28.6  030  10  5   5.1   2.8 |  -2.8  27.0  035  13  7   7.2   3.9
  8250  -1.5  29.3  035   9  4   5.9   3.2 |  -2.2  28.0  040  13  7   7.1   3.9
  8000  -1.1  30.0  035   8  4   6.7   3.7 |  -1.7  28.9  040  13  7   7.0   3.8
  7750  -0.6  30.9  030   7  4   6.3   3.4 |  -1.2  29.8  040  13  7   8.0   4.4
  7500  -0.1  31.8  030   7  4   7.3   4.0 |  -0.5  31.1  040  13  7   8.6   4.7
  7250   0.5  32.9  025   6  3   8.6   4.7 |   0.1  32.2  040  14  7   8.0   4.4
  7000   1.1  34.0  025   6  3   8.4   4.6 |   0.7  33.3  040  15  7   8.0   4.4
  6750   1.8  35.2  025   6  3   9.2   5.0 |   1.2  34.2  040  15  8   8.2   4.5
  6500   2.5  36.5  020   6  3  10.0   5.5 |   1.9  35.4  040  15  8   8.8   4.8
  6250   3.2  37.8  020   5  3  10.0   5.5 |   2.5  36.5  040  13  7   8.9   4.9
  6000   4.0  39.2  020   5  3   9.6   5.3 |   3.2  37.8  040  12  6   9.7   5.3
  5750   4.8  40.6  020   5  2  12.9   7.1 |   3.9  39.0  040  12  6   6.1   3.4
  5500   6.0  42.8  020   5  3  19.5  10.7 |   4.0  39.2  040  10  5  -2.8  -1.5
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

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 at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  Note that some elevations in numerical weather prediction models
differ from actual station elevations, which can lead to data which appear
to be below ground.  Erroneous data such as these should not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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