Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 241241
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0641 MDT Friday, March 24, 2017

This forecast is for Friday, March 24, 2017:

If the trigger temperature of 49.3 F/9.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 553 ft/min (2.8 m/s)
   Maximum height of thermals.................. 14702 ft MSL (9863 ft AGL)

Forecast maximum temperature................... 63.0 F/17.7 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ 1100 MDT
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13499 ft MSL (8659 ft AGL)
Thermal soaring outlook for Saturday 03/25..... Good

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

Remarks...

Sunrise/Sunset.................... 07:10:43 / 19:29:23 MDT
Total possible sunshine........... 12 hr 18 min 41 sec (738 min 41 sec)
Altitude of sun at 13:20:13 MDT... 52.62 degrees

Upper air data from rawinsonde observation taken on 03/24/2017 at 0600 MDT

Freezing level.................. 7976 ft MSL (3137 ft AGL)
Convective condensation level... 11203 ft MSL (6364 ft AGL)
Lifted condensation level....... 13312 ft MSL (8473 ft AGL)
Lifted index.................... +0.9
K index......................... +13.6

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  -56.9 -70.4   255   50   26   4.4   2.4  107.0 224.6    51.1      M    M
 45000  -52.3 -62.1   265   30   15   0.6   0.3   90.1 194.2    44.3      M    M
 40000  -50.5 -58.9   300   20   10  -2.9  -1.6   68.5 155.4    33.4      M    M
 38000  -52.4 -62.3   310   29   15   3.6   2.0   56.8 134.3    26.5      M    M
 36000  -56.3 -69.3   335   36   18  -1.3  -0.7   42.6 108.7    17.4      M    M
 34000  -52.7 -62.9   340   41   21   8.2   4.5   39.3 102.8    15.6      M    M
 32000  -50.8 -59.4   355   42   22   5.8   3.2   33.8  92.9    12.0      M    M
 30000  -46.9 -52.4   345   34   18   5.8   3.2   30.3  86.5     9.7      M    M
 29000  -45.2 -49.4   340   28   15   5.9   3.2   28.6  83.6     8.6      M    M
 28000  -43.0 -45.4   335   23   12   8.8   4.9   27.8  82.0     8.1      M    M
 27000  -40.3 -40.5   325   18    9   9.0   4.9   27.5  81.6     8.0      M    M
 26000  -37.6 -35.7   325   14    7   9.0   4.9   27.2  80.9     7.8      M    M
 25000  -34.9 -30.8   330   10    5   9.0   4.9   26.9  80.4     7.7      M    M
 24000  -32.2 -26.0   350   16    8   9.0   4.9   26.6  79.8     7.5      M    M
 23000  -29.6 -21.3   340   17    9   8.8   4.8   26.1  79.0     7.2      M    M
 22000  -27.0 -16.6   335   22   11   8.8   4.8   25.7  78.3     7.0      M    M
 21000  -24.4 -11.9   330   27   14   8.3   4.6   25.4  77.7     6.8      M    M
 20000  -21.9  -7.4   345   29   15   8.3   4.6   24.9  76.8     6.5      M    M
 19500  -20.7  -5.3   350   28   14   8.3   4.6   24.6  76.3     6.3      M    M
 19000  -19.4  -2.9   355   26   14   8.3   4.6   24.4  75.9     6.1      M    M
 18500  -18.2  -0.8   360   25   13   8.3   4.6   24.1  75.4     5.9      M    M
 18000  -17.0   1.4   010   25   13   8.0   4.4   23.9  75.0     5.7      M    M
 17500  -15.7   3.7   005   26   13   3.7   2.0   23.6  74.6     5.5      M    M
 17000  -15.2   4.6   360   26   14   7.7   4.2   22.5  72.6     4.6      M    M
 16500  -14.1   6.6   355   27   14   5.7   3.1   22.1  71.8     4.2      M    M
 16000  -13.8   7.2   350   29   15   3.2   1.8   20.1  68.2     2.4      M    M
 15500  -13.2   8.2   350   27   14   4.0   2.2   19.2  66.5     1.5      M    M
 15000  -12.7   9.1   350   25   13   1.8   1.0   18.1  64.7     0.6      M    M
 14500  -12.7   9.1   355   27   14   2.0   1.1   16.6  61.8    -0.9    744  3.8
 14000  -12.2  10.0   360   30   15   4.0   2.2   15.5  59.9    -1.8    715  3.6
 13500  -12.2  10.0   360   33   17  -5.7  -3.1   14.0  57.2    -3.3    698  3.5
 13000  -11.8  10.8   005   37   19  11.0   6.0   12.8  55.1    -4.4    673  3.4
 12500  -10.4  13.3   005   41   21   9.3   5.1   12.7  54.9    -4.5    617  3.1
 12000   -9.1  15.6   005   44   23   9.2   5.1   12.7  54.8    -4.6    561  2.9
 11500   -7.7  18.1   005   41   21   9.2   5.1   12.6  54.6    -4.7    506  2.6
 11000   -6.4  20.5   005   38   19   6.4   3.5   12.4  54.3    -4.9    452  2.3
 10500   -5.7  21.7   005   35   18   5.0   2.7   11.6  52.9    -5.7    417  2.1
 10250   -5.4  22.3   005   33   17   5.0   2.8   11.2  52.2    -6.1    400  2.0
 10000   -5.1  22.8   005   32   16   4.4   2.4   10.8  51.5    -6.5    382  1.9
  9750   -4.7  23.5   005   28   15   6.6   3.6   10.4  50.8    -7.0    365  1.9
  9500   -4.1  24.6   360   25   13   9.2   5.1   10.4  50.6    -7.1    338  1.7
  9250   -3.4  25.9   360   22   11   8.8   4.8   10.3  50.5    -7.1    311  1.6
  9000   -2.8  27.0   355   19   10   8.9   4.9   10.3  50.5    -7.2    284  1.4
  8750   -2.1  28.2   355   19   10   8.9   4.9   10.2  50.3    -7.3    257  1.3
  8500   -1.5  29.3   350   18    9   8.9   4.9   10.1  50.2    -7.4    230  1.2
  8250   -0.8  30.6   350   18    9   8.9   4.9   10.1  50.1    -7.5    203  1.0
  8000   -0.1  31.8   345   18    9   8.9   4.9   10.0  50.0    -7.5    176  0.9
  7750    0.5  32.9   340   18    9   8.9   4.9    9.9  49.9    -7.6    149  0.8
  7500    1.2  34.2   340   19   10   8.9   4.9    9.9  49.8    -7.7    122  0.6
  7250    1.8  35.2   335   19   10   8.9   4.9    9.8  49.6    -7.8     95  0.5
  7000    2.5  36.5   330   20   10   8.9   4.9    9.7  49.5    -7.9     68  0.3
  6750    3.1  37.6   325   20   10   8.9   4.9    9.7  49.4    -8.0     40  0.2
  6500    3.8  38.8   325   21   11   8.9   4.9    9.6  49.3    -8.1     13  0.1
  6250    4.5  40.1   320   21   11   8.9   4.9    9.5  49.1    -8.2      M    M
  6000    5.1  41.2   315   22   11   8.9   4.9    9.5  49.0    -8.3      M    M
  5750    5.8  42.4   315   20   10   8.8   4.8    9.4  48.9    -8.4      M    M
  5500    6.4  43.5   315   17    9   9.3   5.1    9.3  48.7    -8.5      M    M
  5250    7.1  44.8   315   15    8   7.2   4.0    9.2  48.6    -8.6      M    M
  5000    7.2  45.0   310   12    6  -4.2  -2.3    8.7  47.6    -9.2      M    M

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

           03/24/2017 at 0900 MDT          |       03/24/2017 at 1200 MDT
                                           |
K index... +3.8  LI... +6.0                | K index... -4.9  LI... +6.1
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 -56.9 -70.4  260  31 16   2.5   1.4 | -57.0 -70.6  260  26 14   2.7   1.5
 45000 -53.1 -63.6  270  32 16   1.6   0.9 | -53.0 -63.4  270  33 17   1.1   0.6
 40000 -55.2 -67.4  325  28 14  -1.4  -0.7 | -59.3 -74.7  305  48 25  -4.1  -2.3
 38000 -55.5 -67.9  345  42 21   0.3   0.2 | -59.3 -74.7  325  50 26   3.6   2.0
 36000 -55.3 -67.5  355  68 35   0.3   0.2 | -57.1 -70.8  355  58 30   3.6   2.0
 34000 -54.4 -65.9  360  90 46  10.0   5.5 | -54.5 -66.1  010  73 38   8.0   4.4
 32000 -49.1 -56.4  360  80 41   8.9   4.9 | -49.9 -57.8  005  74 38   7.8   4.3
 30000 -44.0 -47.2  005  70 36   5.4   2.9 | -45.0 -49.0  005  72 37   9.6   5.3
 29000 -42.3 -44.1  360  60 31   5.7   3.1 | -42.1 -43.8  005  66 34   9.6   5.3
 28000 -40.6 -41.1  360  50 26   5.7   3.1 | -38.5 -37.3  360  60 31   9.6   5.3
 27000 -38.4 -37.1  355  38 20   6.6   3.6 | -35.7 -32.3  355  55 28   7.9   4.3
 26000 -36.3 -33.3  350  36 19   7.1   3.9 | -33.4 -28.1  355  54 28   7.8   4.3
 25000 -34.2 -29.6  350  34 18   7.1   3.9 | -31.0 -23.8  350  52 27   7.8   4.3
 24000 -32.0 -25.6  350  32 17   7.5   4.1 | -28.7 -19.7  345  51 26   7.2   3.9
 23000 -29.6 -21.3  350  33 17   8.1   4.4 | -26.7 -16.1  345  49 25   6.7   3.7
 22000 -27.2 -17.0  350  35 18   8.1   4.4 | -24.7 -12.5  345  47 24   6.7   3.7
 21000 -24.8 -12.6  350  35 18   8.0   4.4 | -22.6  -8.7  345  45 23   7.1   3.9
 20000 -22.4  -8.3  350  34 18   8.0   4.4 | -20.5  -4.9  345  43 22   7.1   3.9
 19500 -21.2  -6.2  350  34 18   8.0   4.4 | -19.4  -2.9  345  42 22   7.1   3.9
 19000 -20.0  -4.0  350  34 17   8.0   4.4 | -18.4  -1.1  345  42 21   7.1   3.9
 18500 -18.9  -2.0  350  33 17   7.7   4.2 | -17.3   0.9  345  41 21   6.6   3.6
 18000 -17.8  -0.0  355  33 17   7.5   4.1 | -16.4   2.5  345  39 20   6.5   3.6
 17500 -16.7   1.9  355  32 17   7.4   4.1 | -15.4   4.3  345  38 20   6.3   3.4
 17000 -15.6   3.9  355  33 17   7.1   3.9 | -14.6   5.7  345  37 19   5.1   2.8
 16500 -14.5   5.9  355  33 17   7.2   4.0 | -13.8   7.2  350  35 18   5.0   2.7
 16000 -13.5   7.7  355  33 17   6.7   3.7 | -12.9   8.8  350  34 17   7.4   4.1
 15500 -12.5   9.5  355  33 17   6.6   3.6 | -11.8  10.8  350  33 17   7.4   4.1
 15000 -11.5  11.3  360  33 17   5.8   3.2 | -10.7  12.7  355  31 16   6.7   3.7
 14500 -10.8  12.6  360  33 17   5.2   2.8 |  -9.8  14.4  355  30 16   6.3   3.5
 14000 -10.0  14.0  360  32 17   4.8   2.6 |  -8.9  16.0  360  29 15   5.3   2.9
 13500  -9.5  14.9  360  32 16   3.7   2.1 |  -8.1  17.4  005  28 14   3.8   2.1
 13000  -8.6  16.5  005  31 16   4.3   2.4 |  -7.6  18.3  010  28 14   3.1   1.7
 12500  -8.0  17.6  005  32 16   4.5   2.5 |  -7.2  19.0  015  28 14   3.1   1.7
 12000  -7.4  18.7  010  32 16   4.0   2.2 |  -6.7  19.9  020  28 14   2.9   1.6
 11500  -6.8  19.8  010  31 16   3.8   2.1 |  -6.3  20.7  025  28 14   2.7   1.5
 11000  -6.2  20.8  015  30 15   5.5   3.0 |  -5.8  21.6  025  27 14   5.5   3.0
 10500  -5.3  22.5  015  27 14   6.6   3.6 |  -5.0  23.0  025  24 12   6.4   3.5
 10250  -4.9  23.2  015  25 13   3.1   1.7 |  -4.6  23.7  025  22 12   2.9   1.6
 10000  -4.8  23.4  020  25 13   5.1   2.8 |  -4.5  23.9  025  21 11   4.3   2.3
  9750  -4.1  24.6  020  26 13   9.8   5.4 |  -3.9  25.0  025  19 10   8.8   4.8
  9500  -3.5  25.7  025  27 14   9.3   5.1 |  -3.3  26.1  025  17  9   7.8   4.3
  9250  -2.8  27.0  025  29 15   6.6   3.6 |  -2.8  27.0  025  16  8   7.0   3.8
  9000  -2.5  27.5  030  30 15   4.4   2.4 |  -2.3  27.9  020  15  8   7.9   4.3
  8750  -2.1  28.2  030  31 16   6.6   3.6 |  -1.6  29.1  020  14  7  10.2   5.6
  8500  -1.6  29.1  030  31 16   6.1   3.4 |  -0.9  30.4  020  14  7   9.8   5.4
  8250  -1.2  29.8  030  31 16   4.2   2.3 |  -0.2  31.6  020  13  7   9.0   4.9
  8000  -1.0  30.2  030  29 15   3.2   1.8 |   0.4  32.7  020  13  7   9.0   5.0
  7750  -0.8  30.6  030  27 14   2.8   1.5 |   1.1  34.0  020  12  6   9.8   5.4
  7500  -0.6  30.9  030  24 12   4.8   2.6 |   1.9  35.4  020  12  6  10.1   5.6
  7250  -0.1  31.8  030  21 11   7.3   4.0 |   2.6  36.7  020  12  6  10.3   5.7
  7000   0.4  32.7  030  19 10   7.3   4.0 |   3.4  38.1  020  12  6  10.0   5.5
  6750   1.0  33.8  030  17  9   8.0   4.4 |   4.2  39.6  020  11  6  10.4   5.7
  6500   1.5  34.7  030  15  8   7.5   4.1 |   5.0  41.0  020  11  6  11.2   6.2
  6250   2.1  35.8  030  13  7   7.5   4.1 |   5.8  42.4  020  11  6  12.5   6.9
  6000   2.6  36.7  030  11  5   5.9   3.2 |   6.7  44.1  020  10  5   8.9   4.9
  5750   3.0  37.4  025   7  4   6.9   3.8 |   7.3  45.1  020  10  5  11.1   6.1
  5500   3.6  38.5  025   7  4   9.9   5.4 |   8.5  47.3  020  10  5  17.5   9.6
  5250   4.3  39.7  025   7  4   7.4   4.1 |   9.6  49.3  020  10  5  12.4   6.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           03/24/2017 at 1500 MDT          |       03/24/2017 at 1800 MDT
                                           |
K index... -20.4  LI... +6.4               | K index... -8.8  LI... +6.5
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 -58.5 -73.3  270  24 13   2.5   1.4 | -59.6 -75.3  265  24 13   2.3   1.3
 45000 -54.8 -66.6  295  28 15   0.2   0.1 | -56.2 -69.2  290  22 11  -1.0  -0.5
 40000 -63.1 -81.6  310  60 31  -5.4  -3.0 | -64.5 -84.1  310  51 26  -5.3  -2.9
 38000 -62.1 -79.8  315  61 31   6.5   3.6 | -62.3 -80.1  315  57 29   8.2   4.5
 36000 -58.2 -72.8  330  54 28   6.5   3.6 | -57.4 -71.3  320  59 30   8.2   4.5
 34000 -53.9 -65.0  340  50 26   8.7   4.8 | -52.4 -62.3  320  58 30   8.5   4.7
 32000 -48.7 -55.7  345  50 26   8.7   4.8 | -47.3 -53.1  325  51 26   8.5   4.7
 30000 -43.5 -46.3  345  49 25   8.3   4.6 | -42.4 -44.3  330  44 23   7.8   4.3
 29000 -41.0 -41.8  350  49 25   8.3   4.5 | -40.0 -40.0  335  41 21   7.8   4.3
 28000 -37.9 -36.2  355  49 25   8.3   4.5 | -37.7 -35.9  340  38 19   7.8   4.3
 27000 -35.4 -31.7  355  48 25   9.0   4.9 | -35.3 -31.5  345  35 18   8.6   4.7
 26000 -32.7 -26.9  355  46 23   8.9   4.9 | -32.1 -25.8  345  32 16   8.7   4.8
 25000 -30.1 -22.2  355  44 22   8.9   4.9 | -29.5 -21.1  350  29 15   8.7   4.8
 24000 -27.4 -17.3  355  42 21   8.3   4.6 | -26.9 -16.4  355  28 14   8.5   4.7
 23000 -24.9 -12.8  350  41 21   8.3   4.6 | -24.4 -11.9  345  27 14   8.5   4.7
 22000 -22.4  -8.3  345  42 21   8.3   4.6 | -21.8  -7.2  340  27 14   8.5   4.7
 21000 -20.1  -4.2  340  42 22   6.6   3.6 | -19.4  -2.9  330  27 14   7.2   4.0
 20000 -18.1  -0.6  340  41 21   6.7   3.7 | -17.2   1.0  325  29 15   7.3   4.0
 19500 -17.1   1.2  340  41 21   6.7   3.7 | -16.2   2.8  325  29 15   7.3   4.0
 19000 -16.0   3.2  340  41 21   6.8   3.7 | -15.1   4.8  325  30 16   7.4   4.1
 18500 -15.1   4.8  340  40 21   5.7   3.1 | -14.1   6.6  325  31 16   5.9   3.2
 18000 -14.2   6.4  345  39 20   5.8   3.2 | -13.2   8.2  325  30 16   6.0   3.3
 17500 -13.4   7.9  345  38 19   6.1   3.4 | -12.3   9.9  330  30 15   6.0   3.3
 17000 -12.4   9.7  350  37 19   6.7   3.7 | -11.4  11.5  330  28 15   5.9   3.3
 16500 -11.4  11.5  350  35 18   6.7   3.7 | -10.5  13.1  335  27 14   6.0   3.3
 16000 -10.4  13.3  355  34 18   6.7   3.7 |  -9.5  14.9  340  26 13   6.6   3.6
 15500  -9.4  15.1  360  33 17   6.8   3.7 |  -8.6  16.5  345  25 13   6.6   3.6
 15000  -8.5  16.7  360  31 16   4.7   2.6 |  -7.6  18.3  350  23 12   6.9   3.8
 14500  -7.8  18.0  005  29 15   4.3   2.4 |  -6.5  20.3  355  22 11   6.9   3.8
 14000  -7.2  19.0  005  27 14   4.1   2.2 |  -5.5  22.1  360  20 10   5.8   3.2
 13500  -6.3  20.7  015  24 12   4.2   2.3 |  -4.7  23.5  360  18  9   5.2   2.9
 13000  -5.8  21.6  020  22 11   4.3   2.3 |  -3.8  25.2  010  16  8   1.8   1.0
 12500  -5.2  22.6  020  21 11   4.5   2.4 |  -3.5  25.7  015  14  7   2.4   1.3
 12000  -4.6  23.7  025  20 10   3.3   1.8 |  -3.1  26.4  020  12  6   3.2   1.8
 11500  -4.2  24.4  025  19 10   3.2   1.8 |  -2.7  27.1  020  11  6   3.4   1.9
 11000  -3.7  25.3  020  16  8   4.9   2.7 |  -2.2  28.0  020   9  5   6.0   3.3
 10500  -3.0  26.6  015  12  6   5.4   3.0 |  -1.4  29.5  015   7  4   6.4   3.5
 10250  -2.7  27.1  010  11  5   3.5   1.9 |  -1.0  30.2  015   6  3   4.0   2.2
 10000  -2.4  27.7  010  10  5   6.5   3.5 |  -0.7  30.7  015   5  3   5.7   3.1
  9750  -1.7  28.9  010  10  5  10.5   5.8 |  -0.1  31.8  010   5  2   9.2   5.1
  9500  -1.0  30.2  005   9  5   9.5   5.2 |   0.5  32.9  360   4  2   8.3   4.6
  9250  -0.4  31.3  005   9  5   7.8   4.3 |   1.1  34.0  355   3  2   6.6   3.6
  9000   0.2  32.4  005   8  4   8.7   4.8 |   1.6  34.9  345   2  1   7.6   4.2
  8750   1.0  33.8  005   8  4  11.3   6.2 |   2.3  36.1  330   2  1   9.9   5.5
  8500   1.8  35.2  005   8  4  10.4   5.7 |   3.0  37.4  315   2  1   9.1   5.0
  8250   2.5  36.5  005   8  4  10.0   5.5 |   3.6  38.5  300   2  1   8.4   4.6
  8000   3.3  37.9  005   7  4  10.0   5.5 |   4.3  39.7  295   2  1   8.7   4.8
  7750   4.0  39.2  005   7  4  10.5   5.8 |   4.9  40.8  285   2  1   9.5   5.2
  7500   4.8  40.6  360   7  4  10.2   5.6 |   5.6  42.1  280   2  1   9.6   5.3
  7250   5.6  42.1  360   7  3   9.9   5.4 |   6.4  43.5  275   2  1   9.7   5.3
  7000   6.3  43.3  360   6  3  10.1   5.5 |   7.1  44.8  270   2  1   9.7   5.3
  6750   7.1  44.8  360   6  3  10.6   5.8 |   7.8  46.0  265   2  1  10.1   5.5
  6500   7.9  46.2  360   6  3  10.8   5.9 |   8.6  47.5  265   2  1  10.5   5.7
  6250   8.7  47.7  360   6  3  11.0   6.1 |   9.4  48.9  260   2  1  10.9   6.0
  6000   9.5  49.1  360   5  3  10.1   5.5 |  10.2  50.4  255   3  1   9.7   5.3
  5750  10.3  50.5  360   5  3  12.7   7.0 |  10.9  51.6  255   3  1   9.1   5.0
  5500  11.4  52.5  360   5  3  16.3   8.9 |  11.6  52.9  260   2  1  10.0   5.5
  5250  12.5  54.5  360   5  3  13.5   7.4 |  12.3  54.1  265   2  1   9.2   5.1
  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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