Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 211248
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0548 MST Tuesday, November 21, 2017

This forecast is for Tuesday, November 21, 2017:

If the trigger temperature of 59.4 F/15.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 76 ft/min (0.4 m/s)
   Maximum height of thermals.................. 7928 ft MSL (3089 ft AGL)

Forecast maximum temperature................... 52.0 F/11.6 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
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................. 6731 ft MSL (1891 ft AGL)
Thermal soaring outlook for Wednesday 11/22.... Fair

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

Remarks...

Sunrise/Sunset.................... 07:04:19 / 16:55:50 MST
Total possible sunshine........... 9 hr 51 min 31 sec (591 min 31 sec)
Altitude of sun at 12:00:15 MST... 30.86 degrees

Upper air data from rawinsonde observation taken on 11/21/2017 at 0500 MST

Freezing level.................. 10255 ft MSL (5416 ft AGL)
Convective condensation level... 20686 ft MSL (15847 ft AGL)
Lifted condensation level....... 13846 ft MSL (9007 ft AGL)
Lifted index.................... +14.9
K index......................... +19.0

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  -58.9 -74.0   335   53   27 -12.0  -6.6  102.8 217.0    52.2      M    M
 45000  -69.3 -92.7   310  123   63 -21.4 -11.7   60.2 140.3    30.0      M    M
 40000  -60.0 -76.0   325  118   61   6.8   3.7   51.6 124.9    26.6      M    M
 38000  -57.0 -70.6   330  121   62   8.3   4.5   47.4 117.2    24.4      M    M
 36000  -50.8 -59.4   325  112   58   9.8   5.4   46.9 116.3    24.8      M    M
 34000  -45.0 -49.0   320  111   57   9.8   5.4   46.8 116.3    25.5      M    M
 32000  -40.2 -40.4   315  106   54   5.3   2.9   45.3 113.6    25.0      M    M
 30000  -35.4 -31.7   310  103   53   8.7   4.8   43.9 111.0    24.5      M    M
 29000  -32.8 -27.0   315  102   53   9.3   5.1   43.4 110.2    24.5      M    M
 28000  -31.1 -24.0   315  101   52   4.3   2.4   41.8 107.3    23.6      M    M
 27000  -29.2 -20.6   320  101   52   7.0   3.9   40.4 104.7    22.7      M    M
 26000  -27.1 -16.8   320  101   52   7.0   3.9   39.3 102.8    22.2      M    M
 25000  -25.0 -13.0   325  101   52   7.5   4.1   38.4 101.1    21.7      M    M
 24000  -23.9 -11.0   325   94   48   7.1   3.9   36.2  97.1    20.2      M    M
 23000  -22.8  -9.0   325   84   43  -9.3  -5.1   34.0  93.1    18.5      M    M
 22000  -21.9  -7.4   320   74   38   7.4   4.1   31.6  88.8    16.7      M    M
 21000  -19.7  -3.5   320   73   38   7.3   4.0   30.6  87.1    16.0      M    M
 20000  -17.6   0.3   320   73   38   6.6   3.6   29.8  85.6    15.5      M    M
 19500  -16.3   2.7   320   70   36   5.7   3.1   28.7  83.6    14.6      M    M
 19000  -15.5   4.1   320   67   35   6.0   3.3   27.9  82.3    14.1      M    M
 18500  -14.5   5.9   325   63   33   7.0   3.8   27.4  81.4    13.7      M    M
 18000  -13.4   7.9   325   59   30   7.0   3.8   27.0  80.5    13.4      M    M
 17500  -12.4   9.7   325   55   28   6.1   3.4   26.5  79.6    13.0      M    M
 17000  -11.6  11.1   325   51   26   5.9   3.3   25.7  78.3    12.5      M    M
 16500  -11.0  12.2   325   47   24   2.5   1.4   24.8  76.7    11.7      M    M
 16000  -10.4  13.3   325   43   22   5.5   3.0   23.9  75.0    10.9      M    M
 15500   -9.6  14.7   325   38   20   5.2   2.9   23.1  73.6    10.2      M    M
 15000   -8.8  16.2   325   33   17   6.4   3.5   22.4  72.4     9.6      M    M
 14500   -7.9  17.8   330   28   15   6.6   3.6   21.9  71.5     9.2      M    M
 14000   -6.9  19.6   330   24   12   6.6   3.6   21.4  70.6     8.8      M    M
 13500   -5.9  21.4   325   26   14   6.7   3.6   20.9  69.6     8.3      M    M
 13000   -5.0  23.0   325   29   15   6.7   3.7   20.4  68.7     7.8      M    M
 12500   -4.0  24.8   320   31   16   6.7   3.7   19.9  67.8     7.4      M    M
 12000   -3.0  26.6   320   33   17   6.5   3.6   19.4  66.9     7.0      M    M
 11500   -1.9  28.6   320   30   15   9.4   5.2   19.0  66.3     6.6      M    M
 11000   -1.2  29.8   315   27   14  -0.5  -0.3   18.2  64.8     5.9      M    M
 10500   -0.6  30.9   310   24   13   8.0   4.4   17.3  63.1     5.1      M    M
 10250   -0.0  32.0   310   23   12   7.4   4.1   17.1  62.9     5.0      M    M
 10000    0.5  32.9   310   22   11   6.9   3.8   16.9  62.5     4.8      M    M
  9750    1.1  34.0   305   21   11   7.0   3.8   16.7  62.0     4.6      M    M
  9500    1.6  34.9   305   21   11   7.0   3.8   16.5  61.6     4.4      M    M
  9250    2.1  35.8   305   20   10   6.8   3.8   16.3  61.3     4.3      M    M
  9000    2.7  36.9   300   19   10   7.4   4.1   16.1  60.9     4.1      M    M
  8750    3.2  37.8   300   16    8   5.1   2.8   15.8  60.5     3.9      M    M
  8500    3.5  38.3   295   12    6  -1.1  -0.6   15.2  59.4     3.4      M    M
  8250    3.1  37.6   285    8    4 -13.9  -7.6   14.0  57.1     2.3      M    M
  8000    2.0  35.6   265    4    2 -11.3  -6.2   11.9  53.5     0.5      M    M
  7750    1.6  34.9   270    4    2  -3.9  -2.1   10.8  51.5    -0.6    278  1.4
  7500    1.3  34.3   280    4    2  -1.8  -1.0    9.7  49.4    -1.6    281  1.4
  7250    1.5  34.7   295    4    2   5.1   2.8    9.2  48.5    -2.2    267  1.4
  7000    1.9  35.4   305    4    2   5.1   2.8    8.8  47.8    -2.5    248  1.3
  6750    2.3  36.1   320    2    1   5.0   2.7    8.4  47.2    -2.9    229  1.2
  6500    2.6  36.7   025    1    0   5.6   3.1    8.1  46.5    -3.2    210  1.1
  6250    3.0  37.4   100    2    1   3.2   1.8    7.7  45.9    -3.6    192  1.0
  6000    3.1  37.6   110    4    2   0.8   0.5    7.1  44.8    -4.3    182  0.9
  5750    3.2  37.8   115    5    3   3.5   1.9    6.5  43.7    -4.9    171  0.9
  5500    3.5  38.3   120    5    3   2.1   1.2    6.0  42.9    -5.4    156  0.8
  5250    3.4  38.1   125    6    3  -3.7  -2.0    5.2  41.4    -6.2    151  0.8
  5000    2.9  37.2   125    6    3  -8.0  -4.4    4.0  39.3    -7.4    158  0.8

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

           11/21/2017 at 0800 MST          |       11/21/2017 at 1100 MST
                                           |
K index... +18.0  LI... +3.3               | K index... +11.3  LI... +7.5
CAPE... +13.9  CIN... -12.4                | 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 -66.3 -87.3  325  61 31  -1.5  -0.8 | -68.0 -90.4  325  63 32  -1.8  -1.0
 45000 -67.6 -89.7  320 105 54   4.4   2.4 | -68.8 -91.8  320  97 50   6.8   3.8
 40000 -60.6 -77.1  340 129 66   4.2   2.3 | -58.6 -73.5  335 100 51   7.6   4.2
 38000 -54.9 -66.8  340 121 62   9.1   5.0 | -53.5 -64.3  335  96 50   8.5   4.7
 36000 -49.4 -56.9  335 112 57   9.1   5.0 | -48.4 -55.1  340  93 48   8.5   4.7
 34000 -44.2 -47.6  335 106 54   8.6   4.7 | -43.5 -46.3  340  90 46   8.1   4.4
 32000 -39.0 -38.2  335 102 52   8.6   4.7 | -38.1 -36.6  335  86 44   8.1   4.4
 30000 -34.4 -29.9  330  98 50   7.0   3.9 | -33.4 -28.1  340  83 43   7.5   4.1
 29000 -32.3 -26.1  330  96 49   7.1   3.9 | -31.2 -24.2  340  81 42   7.5   4.1
 28000 -30.2 -22.4  330  94 48   7.1   3.9 | -28.9 -20.0  345  80 41   7.6   4.2
 27000 -28.0 -18.4  325  91 47   7.4   4.1 | -26.8 -16.2  345  78 40   6.9   3.8
 26000 -25.8 -14.4  330  89 46   7.5   4.1 | -24.8 -12.6  340  77 40   6.9   3.8
 25000 -23.5 -10.3  330  86 44   7.5   4.1 | -22.7  -8.9  340  76 39   6.9   3.8
 24000 -21.4  -6.5  330  84 43   5.9   3.2 | -20.6  -5.1  340  76 39   7.4   4.1
 23000 -19.6  -3.3  330  83 43   6.0   3.3 | -18.4  -1.1  340  74 38   7.4   4.1
 22000 -17.3   0.9  335  83 43   6.1   3.4 | -16.2   2.8  340  73 38   7.3   4.0
 21000 -16.1   3.0  335  80 41   2.8   1.6 | -14.3   6.3  340  72 37   4.9   2.7
 20000 -15.3   4.5  335  73 38   2.8   1.5 | -12.9   8.8  340  69 36   4.8   2.7
 19500 -14.9   5.2  330  70 36   2.8   1.5 | -12.2  10.0  340  68 35   4.8   2.7
 19000 -14.5   5.9  330  67 35   2.5   1.4 | -11.5  11.3  340  67 35   4.7   2.6
 18500 -14.3   6.3  330  64 33   1.9   1.0 | -10.9  12.4  340  63 33   2.0   1.1
 18000 -14.0   6.8  335  60 31   1.7   0.9 | -10.7  12.7  340  60 31   1.9   1.1
 17500 -13.6   7.5  335  57 29   4.1   2.3 | -10.4  13.3  340  57 29   1.6   0.9
 17000 -13.0   8.6  335  54 28   4.1   2.2 | -10.2  13.6  340  53 27   1.6   0.9
 16500 -12.4   9.7  335  50 26   4.2   2.3 |  -9.9  14.2  345  49 25   2.7   1.5
 16000 -11.8  10.8  340  47 24   4.3   2.4 |  -9.5  14.9  345  44 22   3.0   1.7
 15500 -11.2  11.8  340  44 23   5.1   2.8 |  -9.1  15.6  345  38 20   3.9   2.1
 15000 -10.2  13.6  345  41 21   7.5   4.1 |  -8.4  16.9  345  36 18   5.1   2.8
 14500  -9.1  15.6  345  39 20   7.4   4.1 |  -7.6  18.3  345  33 17   5.3   2.9
 14000  -7.9  17.8  345  37 19   8.2   4.5 |  -6.8  19.8  345  33 17   6.3   3.5
 13500  -6.7  19.9  345  34 18   8.1   4.4 |  -5.9  21.4  340  32 17   6.3   3.4
 13000  -5.4  22.3  345  32 16   9.1   5.0 |  -5.1  22.8  340  30 16   5.2   2.9
 12500  -4.1  24.6  345  30 15   9.1   5.0 |  -4.3  24.3  340  27 14   5.2   2.8
 12000  -2.9  26.8  345  27 14   7.8   4.3 |  -3.3  26.1  340  24 12   8.2   4.5
 11500  -1.7  28.9  340  24 12   8.0   4.4 |  -2.2  28.0  340  20 10   7.9   4.4
 11000  -0.6  30.9  335  21 11   7.2   4.0 |  -1.1  30.0  335  18  9   7.4   4.1
 10500   0.4  32.7  335  19 10   7.7   4.2 |   0.0  32.0  330  16  8   7.5   4.1
 10250   0.9  33.6  335  19 10   5.1   2.8 |   0.5  32.9  330  15  8   5.2   2.8
 10000   1.2  34.2  330  18  9   4.0   2.2 |   0.8  33.4  330  15  8   5.4   3.0
  9750   1.6  34.9  330  18  9   6.0   3.3 |   1.3  34.3  330  14  7   8.0   4.4
  9500   2.0  35.6  325  18  9   5.6   3.1 |   1.9  35.4  330  13  7   6.6   3.6
  9250   2.4  36.3  320  17  9   3.8   2.1 |   2.3  36.1  330  13  7   3.9   2.1
  9000   2.6  36.7  315  17  9   2.3   1.3 |   2.5  36.5  325  12  6   2.5   1.4
  8750   2.8  37.0  315  16  8   1.8   1.0 |   2.7  36.9  325  11  6   3.0   1.6
  8500   3.0  37.4  310  14  7   0.8   0.4 |   2.9  37.2  325   9  5   1.4   0.8
  8250   3.0  37.4  305  12  6  -0.1  -0.0 |   3.0  37.4  325   8  4  -0.3  -0.2
  8000   3.1  37.6  300  10  5  -0.2  -0.1 |   3.0  37.4  325   6  3  -0.3  -0.2
  7750   3.1  37.6  295   8  4  -0.4  -0.2 |   3.0  37.4  325   4  2  -0.5  -0.2
  7500   3.1  37.6  285   6  3   1.3   0.7 |   3.1  37.6  325   2  1   2.4   1.3
  7250   3.4  38.1  280   5  3   2.8   1.5 |   3.5  38.3  315   1  0   4.9   2.7
  7000   3.6  38.5  270   4  2   2.4   1.3 |   3.8  38.8  000   0  0   3.8   2.1
  6750   3.8  38.8  250   3  2   2.7   1.5 |   4.2  39.6  165   1  1   6.3   3.4
  6500   4.1  39.4  235   2  1   2.4   1.3 |   4.8  40.6  165   2  1   8.9   4.9
  6250   4.2  39.6  210   2  1   2.7   1.5 |   5.5  41.9  170   2  1   8.7   4.8
  6000   4.4  39.9  190   3  1   0.9   0.5 |   6.2  43.2  175   2  1   8.6   4.7
  5750   4.2  39.6  185   4  2  -5.9  -3.3 |   6.9  44.4  175   2  1  13.2   7.3
  5500   3.5  38.3  165   3  2 -11.4  -6.2 |   8.2  46.8  175   2  1  21.3  11.7
  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

           11/21/2017 at 1400 MST          |       11/21/2017 at 1700 MST
                                           |
K index... +1.1  LI... +9.0                | K index... -3.0  LI... +8.6
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 -69.0 -92.2  325  63 32  -2.0  -1.1 | -69.7 -93.5  330  61 31  -1.2  -0.7
 45000 -69.6 -93.3  325  91 47   7.2   4.0 | -69.3 -92.7  330  87 45   7.1   3.9
 40000 -58.8 -73.8  330  84 43   8.0   4.4 | -58.6 -73.5  335  84 43   8.3   4.6
 38000 -53.6 -64.5  335  83 43   8.5   4.7 | -53.4 -64.1  335  84 43   8.6   4.7
 36000 -48.5 -55.3  340  83 43   8.5   4.7 | -48.2 -54.8  335  83 43   8.6   4.7
 34000 -42.9 -45.2  345  82 42   8.2   4.5 | -42.7 -44.9  340  79 41   7.9   4.4
 32000 -38.0 -36.4  345  80 41   8.2   4.5 | -38.0 -36.4  340  75 39   8.0   4.4
 30000 -33.1 -27.6  345  77 39   8.2   4.5 | -32.9 -27.2  340  69 35   8.7   4.8
 29000 -30.6 -23.1  340  74 38   8.2   4.5 | -30.2 -22.4  340  65 34   8.7   4.8
 28000 -28.2 -18.8  340  72 37   8.4   4.6 | -27.6 -17.7  340  62 32   8.7   4.8
 27000 -26.0 -14.8  340  69 35   6.9   3.8 | -25.1 -13.2  340  56 29   8.3   4.5
 26000 -24.0 -11.2  340  64 33   6.9   3.8 | -22.6  -8.7  335  51 26   8.3   4.6
 25000 -21.9  -7.4  340  60 31   6.9   3.8 | -20.2  -4.4  335  46 24   8.3   4.6
 24000 -19.9  -3.8  345  58 30   6.4   3.5 | -18.4  -1.1  335  44 22   4.2   2.3
 23000 -18.0  -0.4  345  57 29   6.4   3.5 | -17.2   1.0  335  44 23   4.1   2.3
 22000 -16.1   3.0  340  56 29   6.4   3.5 | -16.0   3.2  335  45 23   4.1   2.3
 21000 -14.1   6.6  345  56 29   7.0   3.8 | -14.3   6.3  335  45 23   6.6   3.6
 20000 -12.0  10.4  345  56 29   7.0   3.8 | -12.3   9.9  340  44 23   6.7   3.7
 19500 -10.4  13.3  350  56 29   7.1   3.9 | -10.8  12.6  340  43 22   6.6   3.6
 19000  -9.5  14.9  350  56 29   4.8   2.6 |  -9.8  14.4  340  43 22   7.2   3.9
 18500  -8.8  16.2  350  55 28   4.4   2.4 |  -8.8  16.2  345  42 22   7.1   3.9
 18000  -8.2  17.2  350  54 28   3.9   2.1 |  -7.7  18.1  345  41 21   6.8   3.7
 17500  -7.8  18.0  350  52 27   1.6   0.9 |  -6.8  19.8  350  41 21   6.0   3.3
 17000  -7.6  18.3  350  51 26   1.5   0.8 |  -5.8  21.6  350  40 21   6.3   3.4
 16500  -7.3  18.9  350  49 25   3.7   2.1 |  -5.1  22.8  350  40 21   3.4   1.9
 16000  -6.7  19.9  350  47 24   3.9   2.1 |  -4.6  23.7  355  39 20   3.6   2.0
 15500  -6.1  21.0  350  44 23   3.9   2.1 |  -4.0  24.8  355  39 20   4.4   2.4
 15000  -5.5  22.1  350  42 21   3.8   2.1 |  -3.3  26.1  355  38 20   4.8   2.6
 14500  -5.0  23.0  350  39 20   3.8   2.1 |  -2.6  27.3  355  37 19   4.4   2.4
 14000  -4.5  23.9  350  36 18   3.7   2.0 |  -2.0  28.4  355  36 19   3.5   1.9
 13500  -4.0  24.8  345  33 17   3.7   2.0 |  -1.5  29.3  355  35 18   3.4   1.9
 13000  -3.6  25.5  345  30 16   2.3   1.3 |  -1.1  30.0  355  33 17   3.1   1.7
 12500  -3.3  26.1  340  27 14   2.5   1.4 |  -0.6  30.9  355  31 16   3.2   1.8
 12000  -2.8  27.0  340  24 12   4.5   2.5 |  -0.5  31.1  350  28 14   0.1   0.1
 11500  -2.2  28.0  335  20 10   4.3   2.4 |  -0.5  31.1  350  25 13   0.5   0.3
 11000  -1.4  29.5  335  17  9   7.8   4.3 |  -0.4  31.3  345  20 10   2.2   1.2
 10500  -0.3  31.5  330  13  7   7.5   4.1 |  -0.2  31.6  345  14  7   2.5   1.4
 10250   0.2  32.4  330  12  6   5.8   3.2 |   0.0  32.0  340  12  6   5.1   2.8
 10000   0.7  33.3  330  11  6   6.8   3.7 |   0.5  32.9  340  10  5   7.7   4.2
  9750   1.3  34.3  330  10  5   8.9   4.9 |   1.1  34.0  340   8  4   8.3   4.6
  9500   1.9  35.4  335   8  4   7.7   4.2 |   1.7  35.1  340   6  3   7.7   4.2
  9250   2.4  36.3  335   7  4   6.1   3.3 |   2.2  36.0  345   4  2   6.4   3.5
  9000   2.8  37.0  340   7  3   5.7   3.1 |   2.7  36.9  360   3  2   6.3   3.4
  8750   3.3  37.9  345   6  3   7.1   3.9 |   3.2  37.8  030   2  1   7.5   4.1
  8500   3.8  38.8  360   5  3   5.6   3.1 |   3.8  38.8  070   3  2   6.5   3.6
  8250   4.1  39.4  010   4  2   3.4   1.9 |   4.2  39.6  080   4  2   5.1   2.8
  8000   4.4  39.9  025   3  2   3.6   2.0 |   4.6  40.3  090   5  2   5.4   3.0
  7750   4.7  40.5  045   3  1   4.8   2.6 |   5.0  41.0  090   6  3   7.6   4.2
  7500   5.1  41.2  070   2  1   5.7   3.1 |   5.7  42.3  090   7  3   7.7   4.2
  7250   5.6  42.1  075   2  1   5.6   3.1 |   6.2  43.2  090   7  4   6.3   3.5
  7000   6.0  42.8  080   2  1   5.1   2.8 |   6.7  44.1  090   7  4   6.6   3.6
  6750   6.5  43.7  085   2  1   7.0   3.9 |   7.2  45.0  090   8  4   7.1   3.9
  6500   7.2  45.0  090   2  1   9.9   5.4 |   7.8  46.0  090   7  4   7.9   4.3
  6250   7.9  46.2  090   1  1  10.0   5.5 |   8.4  47.1  085   7  3   7.6   4.2
  6000   8.7  47.7  090   1  1   9.8   5.4 |   9.0  48.2  085   6  3   8.5   4.6
  5750   9.5  49.1  090   1  1  13.7   7.5 |   9.5  49.1  085   6  3   4.2   2.3
  5500  10.8  51.4  080   1  1  20.8  11.4 |   9.5  49.1  085   5  2  -5.2  -2.8
  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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