Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 281248
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0648 MDT Sunday, June 28, 2015

This forecast is for Sunday, June 28, 2015:

If the trigger temperature of 90.3 F/32.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1662 ft/min (8.4 m/s)
   Maximum height of thermals.................. 21689 ft MSL (16850 ft AGL)

Forecast maximum temperature................... 99.0 F/37.7 C
Time of trigger temperature.................... 1130 MDT
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................. 10673 ft MSL (5834 ft AGL)
Thermal soaring outlook for Monday 06/29....... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:50:37 / 20:44:08 MDT
Total possible sunshine........... 14 hr 53 min 31 sec (893 min 31 sec)
Altitude of sun at 13:17:26 MDT... 74.11 degrees

Upper air data from rawinsonde observation taken on 06/28/2015 at 0600 MDT

Freezing level.................. 16763 ft MSL (11924 ft AGL)
Convective condensation level... 18375 ft MSL (13536 ft AGL)
Lifted condensation level....... 18934 ft MSL (14095 ft AGL)
Lifted index.................... -2.5
K index......................... +15.8

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  -65.1 -85.2   005   38   19   3.2   1.8   86.0 186.7    28.2      M    M
 45000  -64.2 -83.6   340   38   20   6.7   3.7   62.9 145.3    16.0      M    M
 40000  -54.3 -65.7   355   32   16   7.7   4.2   54.7 130.4    11.7      M    M
 38000  -49.9 -57.8   340   34   17   4.8   2.6   52.5 126.5    10.5      M    M
 36000  -45.4 -49.7   360   30   15   9.1   5.0   50.5 122.9     9.4      M    M
 34000  -39.8 -39.6   350   27   14   9.3   5.1   50.1 122.1     9.3      M    M
 32000  -35.0 -31.0   350   22   11   7.5   4.1   48.9 119.9     8.6      M    M
 30000  -29.9 -21.8   005   20   10   8.3   4.6   46.9 116.4     7.3      M    M
 29000  -27.4 -17.3   005   22   11   8.4   4.6   46.2 115.2     6.9      M    M
 28000  -24.9 -12.8   360   23   12   8.4   4.6   45.7 114.2     6.5      M    M
 27000  -22.4  -8.3   360   25   13   8.5   4.7   45.3 113.5     6.3      M    M
 26000  -20.3  -4.5   360   22   11   6.6   3.6   44.3 111.7     5.5      M    M
 25000  -18.0  -0.4   360   20   10   7.7   4.2   43.4 110.1     4.9      M    M
 24000  -16.0   3.2   360   19   10   3.9   2.1   42.2 108.0     4.0      M    M
 23000  -15.1   4.8   360   14    7   5.5   3.0   39.9 103.9     2.1      M    M
 22000  -13.4   7.9   360    9    5   1.4   0.8   38.5 101.3     0.9      M    M
 21000  -12.0  10.4   355    4    2   8.7   4.8   36.9  98.4    -0.7   1606  8.2
 20000   -9.3  15.3   035    4    2   8.9   4.9   36.6  97.9    -0.8   1493  7.6
 19500   -7.7  18.1   045    4    2   9.8   5.4   36.7  98.0    -0.7   1431  7.3
 19000   -6.5  20.3   035    4    2   9.0   4.9   36.4  97.5    -0.9   1380  7.0
 18500   -5.1  22.8   020    4    2   9.6   5.3   36.4  97.5    -1.0   1323  6.7
 18000   -3.7  25.3   010    4    2   8.5   4.7   36.4  97.5    -1.1   1267  6.4
 17500   -2.6  27.3   360    4    2   9.1   5.0   36.0  96.8    -1.5   1221  6.2
 17000   -1.1  30.0   350    5    2  10.1   5.5   36.1  96.9    -1.4   1160  5.9
 16500    1.1  34.0   340    6    3   9.0   5.0   36.0  96.9    -1.4   1073  5.5
 16000    2.4  36.3   335    6    3   9.1   5.0   36.0  96.7    -1.5   1018  5.2
 15500    3.7  38.7   340    5    3   9.1   5.0   35.8  96.5    -1.7    964  4.9
 15000    5.1  41.2   350    4    2   9.1   5.0   35.8  96.4    -1.8    909  4.6
 14500    6.4  43.5   360    3    2   9.1   5.0   35.7  96.2    -1.9    854  4.3
 14000    7.7  45.9   015    3    2   9.1   5.0   35.6  96.1    -2.0    799  4.1
 13500    9.1  48.4   010    2    1   9.1   5.0   35.5  95.8    -2.1    744  3.8
 13000   10.4  50.7   005    2    1   9.1   5.0   35.3  95.6    -2.3    689  3.5
 12500   11.8  53.2   360    1    1   9.1   5.0   35.3  95.5    -2.4    634  3.2
 12000   13.1  55.6   340    1    1   9.1   5.0   35.2  95.3    -2.5    580  2.9
 11500   14.4  57.9   315    2    1   9.1   5.0   35.0  95.0    -2.7    525  2.7
 11000   15.8  60.4   300    2    1   9.3   5.1   34.9  94.8    -2.9    470  2.4
 10500   17.0  62.6   290    3    1   7.2   4.0   34.7  94.4    -3.1    418  2.1
 10250   17.5  63.5   255    1    1   7.2   3.9   34.4  94.0    -3.4    396  2.0
 10000   18.0  64.4   185    2    1   7.2   4.0   34.2  93.6    -3.6    373  1.9
  9750   18.5  65.3   165    3    2   7.2   4.0   34.0  93.3    -3.8    350  1.8
  9500   19.1  66.4   155    5    3   7.2   4.0   33.8  92.9    -4.0    327  1.7
  9250   19.6  67.3   150    7    4   7.2   4.0   33.7  92.6    -4.2    304  1.5
  9000   20.1  68.2   150    9    5   7.2   4.0   33.5  92.3    -4.5    281  1.4
  8750   20.6  69.1   155   10    5   7.3   4.0   33.3  91.9    -4.7    259  1.3
  8500   21.1  70.0   155   11    6   7.2   3.9   33.1  91.5    -4.9    236  1.2
  8250   21.6  70.9   160   12    6   7.6   4.2   32.9  91.2    -5.1    213  1.1
  8000   22.2  72.0   160   13    7   6.0   3.3   32.7  90.8    -5.4    190  1.0
  7750   22.4  72.3   155   13    6   1.8   1.0   32.2  90.0    -5.8    175  0.9
  7500   22.5  72.5   150   12    6   0.3   0.2   31.5  88.8    -6.5    166  0.8
  7250   22.5  72.5   145   12    6   0.9   0.5   30.8  87.5    -7.2    158  0.8
  7000   22.5  72.5   135   12    6   0.1   0.0   30.1  86.3    -7.9    149  0.8
  6750   22.6  72.7   135   12    6   2.9   1.6   29.5  85.0    -8.7    140  0.7
  6500   23.0  73.4   135   12    6   8.0   4.4   29.2  84.5    -9.0    120  0.6
  6250   23.7  74.7   135   11    6   9.0   4.9   29.1  84.4    -9.1     93  0.5
  6000   24.3  75.7   135   11    6   9.0   4.9   29.0  84.2    -9.1     66  0.3
  5750   25.0  77.0   135   10    5   8.1   4.5   29.0  84.1    -9.2     39  0.2
  5500   25.6  78.1   130    9    5  11.5   6.3   28.9  84.0    -9.3     12  0.1
  5250   26.3  79.3   125    8    4  -1.2  -0.6   28.8  83.9    -9.4      M    M
  5000   24.9  76.8   115    7    4 -35.2 -19.3   26.7  80.1   -11.5     18  0.1

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

           06/28/2015 at 0900 MDT          |       06/28/2015 at 1200 MDT
                                           |
K index... +12.1  LI... +273.9             | K index... +13.0  LI... +271.5
CAPE... 0.0  CIN... -138.3                 | CAPE... +372.1  CIN... -71.3
                                           |
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 -65.3 -85.5  005  22 12   1.1   0.6 | -64.8 -84.6  015  19 10   1.3   0.7
 45000 -61.8 -79.2  350  31 16   4.5   2.4 | -61.3 -78.3  355  29 15   3.9   2.1
 40000 -54.2 -65.6  355  33 17   8.1   4.5 | -54.4 -65.9  350  33 17   8.1   4.5
 38000 -49.4 -56.9  360  34 18   8.1   4.5 | -49.6 -57.3  360  34 17   8.1   4.4
 36000 -44.5 -48.1  005  35 18   8.3   4.5 | -44.7 -48.5  005  35 18   8.3   4.5
 34000 -39.4 -38.9  005  31 16   8.5   4.7 | -39.6 -39.3  010  29 15   8.5   4.7
 32000 -34.3 -29.7  010  27 14   8.7   4.8 | -34.5 -30.1  015  23 12   8.8   4.8
 30000 -29.5 -21.1  010  26 14   8.0   4.4 | -28.8 -19.8  025  22 11   8.4   4.6
 29000 -26.5 -15.7  015  26 13   8.0   4.4 | -26.3 -15.3  025  21 11   8.3   4.6
 28000 -24.3 -11.7  015  25 13   6.4   3.5 | -24.0 -11.2  025  20 10   6.9   3.8
 27000 -22.4  -8.3  015  22 11   6.5   3.5 | -22.0  -7.6  025  18  9   6.9   3.8
 26000 -20.5  -4.9  015  20 10   6.5   3.6 | -19.9  -3.8  020  17  9   7.0   3.8
 25000 -18.6  -1.5  015  18  9   6.9   3.8 | -17.9  -0.2  015  15  8   5.9   3.2
 24000 -16.5   2.3  015  17  9   7.0   3.9 | -16.2   2.8  015  13  7   5.7   3.1
 23000 -14.3   6.3  010  16  8   7.0   3.9 | -14.6   5.7  015  11  6   5.7   3.1
 22000 -12.2  10.0  005  14  7   7.1   3.9 | -12.8   9.0  015  10  5   7.7   4.2
 21000 -10.1  13.8  360  11  6   7.1   3.9 | -10.4  13.3  005   9  5   7.9   4.4
 20000  -7.9  17.8  345   9  4   7.2   3.9 |  -7.9  17.8  360   9  5   8.0   4.4
 19500  -6.9  19.6  340   8  4   7.6   4.2 |  -6.7  19.9  355   9  5   7.8   4.3
 19000  -5.6  21.9  330   7  4   8.3   4.6 |  -5.6  21.9  345   9  4   7.7   4.2
 18500  -4.4  24.1  325   7  3   8.3   4.6 |  -4.5  23.9  335   8  4   7.6   4.2
 18000  -3.1  26.4  325   6  3   8.6   4.7 |  -3.3  26.1  330   8  4   8.6   4.7
 17500  -1.9  28.6  325   6  3   8.6   4.7 |  -2.0  28.4  325   8  4   8.7   4.8
 17000  -0.6  30.9  325   6  3   8.7   4.8 |  -0.8  30.6  325   8  4   8.8   4.8
 16500   0.7  33.3  330   6  3   8.7   4.8 |   0.5  32.9  325   7  4   9.0   4.9
 16000   1.9  35.4  335   6  3   8.8   4.8 |   1.8  35.2  325   7  4   9.0   4.9
 15500   3.2  37.8  340   6  3   8.8   4.8 |   3.1  37.6  325   6  3   9.1   5.0
 15000   4.5  40.1  345   5  3   8.9   4.9 |   4.5  40.1  320   6  3   9.1   5.0
 14500   5.8  42.4  350   5  3   9.0   4.9 |   6.5  43.7  320   5  2   8.8   4.8
 14000   7.7  45.9  360   5  2   9.1   5.0 |   7.9  46.2  320   4  2   8.8   4.9
 13500   9.1  48.4  010   4  2   8.8   4.8 |   9.2  48.6  315   4  2   8.9   4.9
 13000  10.4  50.7  010   4  2   8.8   4.8 |  10.5  50.9  315   3  2   8.9   4.9
 12500  11.7  53.1  015   4  2   8.7   4.8 |  11.8  53.2  310   3  2   8.9   4.9
 12000  13.0  55.4  020   3  2   8.7   4.8 |  13.1  55.6  300   3  1   9.0   4.9
 11500  14.3  57.7  025   2  1   7.9   4.3 |  14.4  57.9  285   3  1   8.2   4.5
 11000  15.4  59.7  035   1  1   8.0   4.4 |  15.6  60.1  265   3  1   8.4   4.6
 10500  16.3  61.3  085   1  0   3.9   2.2 |  16.6  61.9  245   3  1   4.8   2.6
 10250  16.7  62.1  130   1  0   7.1   3.9 |  17.0  62.6  240   3  2   7.8   4.3
 10000  17.4  63.3  155   1  1  10.0   5.5 |  17.7  63.9  235   3  2   9.6   5.3
  9750  18.0  64.4  165   2  1   9.0   4.9 |  18.4  65.1  225   4  2   8.9   4.9
  9500  18.6  65.5  170   3  1   6.5   3.6 |  18.9  66.0  225   4  2   6.9   3.8
  9250  19.0  66.2  170   3  2   6.3   3.5 |  19.4  66.9  225   4  2   7.0   3.9
  9000  19.6  67.3  175   4  2   8.6   4.7 |  20.0  68.0  220   4  2   8.6   4.7
  8750  20.2  68.4  175   5  2   7.9   4.4 |  20.6  69.1  220   5  2   8.1   4.4
  8500  20.7  69.3  175   6  3   6.3   3.5 |  21.1  70.0  220   5  3   7.4   4.1
  8250  21.1  70.0  175   7  3   5.6   3.1 |  21.5  70.7  220   5  3   7.3   4.0
  8000  21.4  70.5  170   8  4   5.6   3.1 |  22.0  71.6  220   5  3   7.3   4.0
  7750  21.7  71.1  170   9  4   4.0   2.2 |  22.4  72.3  215   5  3   8.2   4.5
  7500  21.9  71.4  165   9  5   2.2   1.2 |  23.0  73.4  215   5  3   9.5   5.2
  7250  22.0  71.6  165   9  5   2.3   1.3 |  23.7  74.7  215   5  3   9.7   5.3
  7000  22.1  71.8  160   9  5   1.2   0.7 |  24.4  75.9  215   5  3   9.7   5.3
  6750  22.1  71.8  160   9  5   1.4   0.7 |  25.1  77.2  220   5  3  10.6   5.8
  6500  22.2  72.0  155   8  4   2.6   1.4 |  25.9  78.6  220   5  3  11.0   6.0
  6250  22.3  72.1  155   7  4   2.5   1.4 |  26.7  80.1  220   5  3  11.2   6.1
  6000  22.5  72.5  150   6  3   1.8   1.0 |  27.6  81.7  220   5  3  10.0   5.5
  5750  22.6  72.7  145   5  2   6.5   3.6 |  28.3  82.9  220   5  2  12.3   6.7
  5500  23.4  74.1  145   5  2  11.8   6.5 |  29.4  84.9  220   5  2  15.9   8.7
  5250  24.1  75.4  140   5  2   7.7   4.2 |  30.5  86.9  225   5  2  13.1   7.2
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           06/28/2015 at 1500 MDT          |       06/28/2015 at 1800 MDT
                                           |
K index... +18.3  LI... +272.8             | K index... +17.9  LI... +273.5
CAPE... +58.2  CIN... -58.1                | CAPE... 0.0  CIN... -6.7
                                           |
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 -65.3 -85.5  020  14  7   2.1   1.1 | -65.5 -85.9  025  14  7   2.0   1.1
 45000 -61.0 -77.8  360  24 12   3.9   2.2 | -60.9 -77.6  005  20 11   4.4   2.4
 40000 -54.1 -65.4  360  31 16   8.0   4.4 | -53.4 -64.1  010  29 15   8.0   4.4
 38000 -49.3 -56.7  005  31 16   7.9   4.4 | -48.7 -55.7  010  31 16   8.0   4.4
 36000 -44.6 -48.3  015  32 17   8.4   4.6 | -43.9 -47.0  010  32 17   8.4   4.6
 34000 -39.2 -38.6  015  29 15   8.9   4.9 | -38.6 -37.5  015  27 14   8.7   4.8
 32000 -33.2 -27.8  020  25 13   8.7   4.8 | -32.8 -27.0  020  22 11   8.7   4.8
 30000 -28.2 -18.8  020  19 10   8.3   4.6 | -27.8 -18.0  015  19 10   8.2   4.5
 29000 -25.8 -14.4  020  16  8   8.3   4.6 | -25.4 -13.7  015  18  9   8.2   4.5
 28000 -23.3  -9.9  020  14  7   7.7   4.2 | -23.0  -9.4  015  17  9   7.3   4.0
 27000 -21.0  -5.8  020  14  7   7.7   4.2 | -20.8  -5.4  010  15  8   7.4   4.1
 26000 -18.8  -1.8  020  14  7   7.8   4.3 | -18.6  -1.5  005  14  7   7.4   4.1
 25000 -16.6   2.1  020  13  7   5.6   3.1 | -16.5   2.3  360  13  7   6.1   3.3
 24000 -15.1   4.8  015  12  6   5.2   2.8 | -14.8   5.4  355  14  7   5.8   3.2
 23000 -13.5   7.7  005  11  6   5.2   2.9 | -13.1   8.4  355  14  7   5.8   3.2
 22000 -11.9  10.6  355  10  5   7.5   4.1 | -11.3  11.7  350  15  8   7.1   3.9
 21000  -9.6  14.7  355  11  5   7.7   4.2 |  -9.2  15.4  345  15  8   7.3   4.0
 20000  -7.3  18.9  350  11  6   7.7   4.2 |  -7.0  19.4  340  15  8   7.4   4.1
 19500  -6.2  20.8  350  11  6   7.8   4.3 |  -6.0  21.2  340  15  8   7.8   4.3
 19000  -5.0  23.0  350  10  5   8.0   4.4 |  -4.7  23.5  340  15  8   8.6   4.7
 18500  -3.7  25.3  350  10  5   8.0   4.4 |  -3.5  25.7  335  15  8   8.6   4.7
 18000  -2.5  27.5  345   9  5   8.1   4.4 |  -2.2  28.0  335  15  8   8.7   4.8
 17500  -1.3  29.7  340   9  5   8.1   4.4 |  -1.0  30.2  335  14  7   8.8   4.8
 17000  -0.1  31.8  335   9  5   8.1   4.5 |   0.3  32.5  335  14  7   8.8   4.8
 16500   1.1  34.0  330   9  5   8.3   4.6 |   1.6  34.9  335  13  7   8.9   4.9
 16000   2.3  36.1  325   9  5   8.4   4.6 |   3.0  37.4  335  13  6   8.9   4.9
 15500   3.5  38.3  320  10  5   8.9   4.9 |   4.3  39.7  340  12  6   8.8   4.8
 15000   5.4  41.7  315   9  5   9.0   4.9 |   6.3  43.3  340  11  6   8.8   4.8
 14500   6.7  44.1  310   9  5   9.5   5.2 |   7.6  45.7  340  10  5   9.1   5.0
 14000   8.0  46.4  305   9  5   9.5   5.2 |   9.0  48.2  340  10  5   9.1   5.0
 13500   9.4  48.9  305   9  4   9.1   5.0 |  10.4  50.7  335   9  4   9.1   5.0
 13000  10.8  51.4  300   8  4   9.1   5.0 |  11.7  53.1  335   8  4   9.2   5.0
 12500  12.1  53.8  300   8  4   9.3   5.1 |  13.1  55.6  335   7  4   9.0   4.9
 12000  13.6  56.5  295   7  4   9.4   5.2 |  14.4  57.9  325   6  3   9.0   4.9
 11500  15.0  59.0  295   7  4   8.9   4.9 |  15.8  60.4  320   5  3   8.9   4.9
 11000  16.3  61.3  290   7  3   9.1   5.0 |  17.1  62.8  310   5  2   9.1   5.0
 10500  17.4  63.3  290   6  3   5.9   3.2 |  18.3  64.9  300   4  2   5.6   3.1
 10250  18.0  64.4  285   6  3   9.4   5.2 |  18.7  65.7  290   4  2   8.0   4.4
 10000  18.8  65.8  285   6  3  10.6   5.8 |  19.5  67.1  285   4  2  10.8   5.9
  9750  19.6  67.3  285   6  3  10.3   5.6 |  20.2  68.4  275   4  2  10.5   5.8
  9500  20.3  68.5  280   5  3   6.7   3.7 |  21.0  69.8  270   4  2   8.6   4.7
  9250  20.7  69.3  280   5  3   6.9   3.8 |  21.5  70.7  260   4  2   7.8   4.3
  9000  21.3  70.3  280   5  3   9.9   5.4 |  22.2  72.0  250   4  2   9.4   5.1
  8750  22.0  71.6  280   5  3   8.9   4.9 |  22.8  73.0  245   4  2   9.0   4.9
  8500  22.6  72.7  280   5  3   8.0   4.4 |  23.5  74.3  240   4  2   8.8   4.8
  8250  23.1  73.6  280   5  3   7.8   4.3 |  24.1  75.4  235   4  2   8.2   4.5
  8000  23.7  74.7  280   5  3   9.7   5.3 |  24.6  76.3  230   3  2   7.5   4.1
  7750  24.4  75.9  280   5  2  10.4   5.7 |  25.2  77.4  225   3  2   7.3   4.0
  7500  25.1  77.2  280   5  2  10.1   5.5 |  25.8  78.4  220   3  2   9.3   5.1
  7250  25.9  78.6  280   5  3  10.1   5.5 |  26.5  79.7  220   3  2  10.7   5.9
  7000  26.6  79.9  280   5  3  10.0   5.5 |  27.3  81.1  220   3  2   9.5   5.2
  6750  27.4  81.3  275   5  2  10.3   5.7 |  27.9  82.2  215   4  2   9.2   5.1
  6500  28.2  82.8  275   5  2  10.8   5.9 |  28.7  83.7  215   4  2  10.4   5.7
  6250  29.0  84.2  275   5  2  10.9   6.0 |  29.5  85.1  215   4  2  11.0   6.0
  6000  29.8  85.6  275   5  2  10.6   5.8 |  30.2  86.4  215   4  2   9.5   5.2
  5750  30.6  87.1  275   5  2  13.1   7.2 |  30.9  87.6  215   4  2   9.4   5.2
  5500  31.7  89.1  275   5  2  15.8   8.7 |  31.7  89.1  215   3  2  11.2   6.1
  5250  32.8  91.0  280   5  2  13.7   7.5 |  32.5  90.5  215   3  2  10.1   5.5
  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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