Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 181242
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0642 MDT Tuesday, April 18, 2017

This forecast is for Tuesday, April 18, 2017:

If the trigger temperature of 69.7 F/20.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 788 ft/min (4.0 m/s)
   Maximum height of thermals.................. 15277 ft MSL (10438 ft AGL)

Forecast maximum temperature................... 79.0 F/26.6 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12416 ft MSL (7577 ft AGL)
Thermal soaring outlook for Wednesday 04/19.... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:32:41 / 19:53:49 MDT
Total possible sunshine........... 13 hr 21 min 8 sec (801 min 8 sec)
Altitude of sun at 13:13:25 MDT... 61.98 degrees

Upper air data from rawinsonde observation taken on 04/18/2017 at 0600 MDT

Freezing level.................. 12504 ft MSL (7665 ft AGL)
Convective condensation level... 18631 ft MSL (13792 ft AGL)
Lifted condensation level....... 17315 ft MSL (12476 ft AGL)
Lifted index.................... +2.9
K index......................... +16.9

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  -65.9 -86.6   285   56   29  -0.1  -0.0   88.8 191.9    35.9      M    M
 45000  -61.0 -77.8   295   81   41   5.7   3.1   71.1 160.0    27.7      M    M
 40000  -56.0 -68.8   285   90   46   1.0   0.5   56.3 133.3    19.9      M    M
 38000  -55.3 -67.5   280   80   41   2.1   1.1   48.5 119.3    15.2      M    M
 36000  -53.3 -63.9   270   70   36   2.9   1.6   43.0 109.4    11.8      M    M
 34000  -48.5 -55.3   265   69   36   9.2   5.0   41.6 106.8    11.0      M    M
 32000  -43.0 -45.4   270   64   33   8.3   4.5   41.1 106.0    11.0      M    M
 30000  -37.2 -35.0   275   60   31   8.3   4.6   40.2 104.3    10.5      M    M
 29000  -34.7 -30.5   275   51   26   8.3   4.6   39.6 103.2    10.2      M    M
 28000  -32.2 -26.0   275   42   21   8.3   4.6   39.1 102.4    10.0      M    M
 27000  -29.7 -21.5   265   38   20   8.3   4.6   38.4 101.2     9.6      M    M
 26000  -27.3 -17.1   250   37   19   3.0   1.7   37.8 100.1     9.2      M    M
 25000  -25.6 -14.1   235   37   19   8.7   4.8   36.3  97.4     8.1      M    M
 24000  -23.1  -9.6   235   39   20   7.6   4.2   35.8  96.4     7.7      M    M
 23000  -20.8  -5.4   240   41   21   7.7   4.2   35.0  95.0     7.1      M    M
 22000  -18.7  -1.7   245   44   23   4.5   2.4   34.1  93.4     6.5      M    M
 21000  -17.5   0.5   245   39   20   3.8   2.1   32.1  89.8     4.8      M    M
 20000  -15.4   4.3   245   34   18   8.5   4.7   31.2  88.1     4.1      M    M
 19500  -14.2   6.4   245   34   17   8.5   4.7   30.9  87.7     3.9      M    M
 19000  -12.9   8.8   250   33   17   8.5   4.7   30.7  87.3     3.7      M    M
 18500  -11.6  11.1   250   33   17   8.9   4.9   30.6  87.0     3.6      M    M
 18000  -10.6  12.9   245   32   17   5.0   2.7   30.0  86.0     3.1      M    M
 17500   -9.8  14.4   245   32   16   5.2   2.9   29.3  84.7     2.4      M    M
 17000   -8.5  16.7   240   31   16   6.6   3.6   28.3  83.0     1.6      M    M
 16500   -7.5  18.5   235   31   16   6.6   3.6   27.8  82.1     1.2      M    M
 16000   -6.5  20.3   235   31   16   6.5   3.6   27.3  81.2     0.7      M    M
 15500   -5.5  22.1   230   29   15   5.1   2.8   26.8  80.2     0.2      M    M
 15000   -4.9  23.2   225   28   14   0.6   0.4   25.8  78.5    -0.6    864  4.4
 14500   -5.5  22.1   215   27   14   3.7   2.0   23.7  74.6    -2.7    866  4.4
 14000   -4.1  24.6   210   26   13   9.0   5.0   23.6  74.5    -2.7    810  4.1
 13500   -2.7  27.1   215   25   13   9.4   5.2   23.5  74.4    -2.8    753  3.8
 13000   -1.3  29.7   215   24   12   9.5   5.2   23.5  74.3    -2.9    696  3.5
 12500    0.1  32.2   220   24   12   9.4   5.2   23.4  74.2    -3.0    640  3.2
 12000    1.4  34.5   225   23   12   5.4   3.0   23.3  74.0    -3.1    586  3.0
 11500    1.8  35.2   230   22   11   5.8   3.2   22.2  71.9    -4.3    561  2.8
 11000    3.1  37.6   240   22   11   9.2   5.1   22.0  71.7    -4.4    506  2.6
 10500    4.5  40.1   245   22   11   9.4   5.1   22.0  71.6    -4.5    450  2.3
 10250    5.2  41.4   250   22   11   9.2   5.0   22.0  71.5    -4.6    422  2.1
 10000    5.9  42.6   250   22   11   8.8   4.9   21.9  71.4    -4.7    394  2.0
  9750    6.5  43.7   250   22   11   8.8   4.8   21.8  71.3    -4.7    367  1.9
  9500    7.2  45.0   245   21   11   8.8   4.8   21.8  71.2    -4.8    340  1.7
  9250    7.8  46.0   245   21   11   8.8   4.8   21.7  71.1    -4.8    312  1.6
  9000    8.5  47.3   245   21   11   8.8   4.8   21.7  71.0    -4.9    285  1.4
  8750    9.2  48.6   245   20   10   8.8   4.8   21.6  70.8    -5.0    258  1.3
  8500    9.8  49.6   245   19   10   8.8   4.8   21.5  70.7    -5.1    230  1.2
  8250   10.5  50.9   240   18    9   8.8   4.8   21.4  70.6    -5.1    203  1.0
  8000   11.2  52.2   240   17    9   8.8   4.8   21.4  70.5    -5.2    176  0.9
  7750   11.8  53.2   240   16    8   8.8   4.8   21.3  70.3    -5.3    148  0.8
  7500   12.5  54.5   240   16    8   8.8   4.8   21.2  70.2    -5.4    121  0.6
  7250   13.2  55.8   245   15    8   8.8   4.8   21.1  70.1    -5.4     94  0.5
  7000   13.8  56.8   245   14    7   8.8   4.9   21.1  69.9    -5.5     66  0.3
  6750   14.5  58.1   235   12    6   8.7   4.8   21.0  69.8    -5.6     39  0.2
  6500   15.2  59.4   220   10    5   9.1   5.0   20.9  69.6    -5.7     12  0.1
  6250   15.8  60.4   200    9    5   7.6   4.2   20.8  69.5    -5.8      M    M
  6000   16.2  61.2   175   10    5   2.7   1.5   20.5  68.9    -6.1      M    M
  5750   16.3  61.3   160    9    5   0.3   0.2   19.8  67.7    -6.8      M    M
  5500   16.2  61.2   150    8    4  -8.6  -4.7   18.9  66.0    -7.7      M    M
  5250   15.1  59.2   130    7    4 -15.7  -8.6   17.1  62.8    -9.5      M    M
  5000   14.1  57.4   110    7    4 -13.2  -7.2   15.3  59.6   -11.3      0  0.0

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

           04/18/2017 at 0900 MDT          |       04/18/2017 at 1200 MDT
                                           |
K index... +18.4  LI... +3.6               | K index... +6.6  LI... +4.0
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 -65.2 -85.4  295  54 28   3.1   1.7 | -64.8 -84.6  285  45 23   3.1   1.7
 45000 -60.6 -77.1  295  75 39   2.8   1.5 | -59.9 -75.8  280  63 32   2.9   1.6
 40000 -56.3 -69.3  280  90 46   2.6   1.4 | -55.5 -67.9  275  88 46   2.8   1.5
 38000 -53.7 -64.7  280  81 42   4.5   2.5 | -53.1 -63.6  270  84 43   4.1   2.3
 36000 -51.0 -59.8  275  71 37   4.5   2.5 | -50.7 -59.3  270  78 40   4.1   2.3
 34000 -47.3 -53.1  270  66 34   8.2   4.5 | -47.0 -52.6  265  74 38   8.1   4.5
 32000 -42.4 -44.3  270  66 34   8.2   4.5 | -42.2 -44.0  260  72 37   8.1   4.5
 30000 -37.5 -35.5  270  63 33   8.2   4.5 | -36.8 -34.2  260  65 34   7.8   4.3
 29000 -35.0 -31.0  270  60 31   8.2   4.5 | -34.5 -30.1  260  60 31   7.8   4.3
 28000 -32.0 -25.6  270  56 29   8.2   4.5 | -32.2 -26.0  265  54 28   7.8   4.3
 27000 -29.7 -21.5  270  52 27   7.3   4.0 | -29.9 -21.8  260  50 26   7.6   4.1
 26000 -27.5 -17.5  270  49 25   7.3   4.0 | -27.6 -17.7  255  46 24   7.6   4.2
 25000 -25.3 -13.5  265  45 23   7.3   4.0 | -25.3 -13.5  250  43 22   7.6   4.2
 24000 -23.1  -9.6  265  42 22   8.0   4.4 | -23.0  -9.4  245  42 22   7.1   3.9
 23000 -20.7  -5.3  260  40 21   8.0   4.4 | -20.9  -5.6  240  44 22   7.2   3.9
 22000 -18.3  -0.9  255  38 20   8.0   4.4 | -18.7  -1.7  240  45 23   7.2   3.9
 21000 -16.2   2.8  255  37 19   6.4   3.5 | -16.6   2.1  240  46 24   7.0   3.8
 20000 -14.3   6.3  255  37 19   6.3   3.5 | -14.5   5.9  240  46 24   7.0   3.9
 19500 -13.4   7.9  255  38 19   6.4   3.5 | -13.5   7.7  245  46 24   7.0   3.9
 19000 -12.4   9.7  250  38 19   6.4   3.5 | -12.4   9.7  245  46 24   7.0   3.9
 18500 -11.6  11.1  250  37 19   5.5   3.0 | -11.4  11.5  245  45 23   6.4   3.5
 18000 -10.7  12.7  250  37 19   5.6   3.1 | -10.5  13.1  245  43 22   6.5   3.5
 17500  -9.9  14.2  250  36 18   5.7   3.2 |  -9.5  14.9  250  42 21   6.0   3.3
 17000  -9.1  15.6  250  35 18   5.9   3.2 |  -8.7  16.3  250  40 21   5.7   3.1
 16500  -8.2  17.2  250  34 17   6.0   3.3 |  -7.8  18.0  250  38 20   5.8   3.2
 16000  -7.3  18.9  250  33 17   6.8   3.7 |  -7.0  19.4  245  37 19   6.3   3.5
 15500  -6.4  20.5  250  32 16   6.8   3.7 |  -6.0  21.2  245  36 18   6.3   3.5
 15000  -5.4  22.3  250  31 16   7.1   3.9 |  -5.1  22.8  245  35 18   6.7   3.7
 14500  -4.3  24.3  245  30 15   7.2   3.9 |  -4.1  24.6  245  34 17   6.7   3.7
 14000  -3.3  26.1  245  29 15   6.3   3.4 |  -2.7  27.1  245  32 16   6.1   3.3
 13500  -2.0  28.4  240  28 14   6.0   3.3 |  -1.8  28.8  245  30 16   6.2   3.4
 13000  -1.2  29.8  235  26 14   5.2   2.9 |  -1.0  30.2  245  29 15   5.7   3.1
 12500  -0.4  31.3  235  25 13   5.2   2.9 |  -0.1  31.8  245  28 15   5.8   3.2
 12000   0.4  32.7  235  24 12   6.3   3.5 |   0.6  33.1  240  27 14   4.9   2.7
 11500   1.3  34.3  235  24 12   6.4   3.5 |   1.3  34.3  235  25 13   4.9   2.7
 11000   2.2  36.0  235  23 12   5.3   2.9 |   2.0  35.6  230  23 12   5.8   3.2
 10500   3.0  37.4  235  22 11   4.3   2.4 |   2.9  37.2  225  20 10   4.9   2.7
 10250   3.4  38.1  235  21 11   9.2   5.1 |   3.3  37.9  220  19 10   9.8   5.4
 10000   4.3  39.7  230  21 11  10.6   5.8 |   4.2  39.6  220  18  9  11.9   6.5
  9750   4.8  40.6  230  20 10   6.5   3.6 |   4.9  40.8  220  17  9   8.4   4.6
  9500   5.4  41.7  230  19 10   7.9   4.3 |   5.6  42.1  215  16  8   9.4   5.2
  9250   6.0  42.8  230  18  9   6.4   3.5 |   6.2  43.2  215  15  8   8.8   4.8
  9000   6.4  43.5  225  17  9   6.3   3.5 |   6.9  44.4  220  15  8   9.7   5.3
  8750   6.9  44.4  225  16  8   7.4   4.1 |   7.7  45.9  220  15  8  10.5   5.8
  8500   7.5  45.5  225  16  8   7.1   3.9 |   8.5  47.3  220  14  7  10.3   5.6
  8250   8.0  46.4  225  15  8   7.8   4.3 |   9.2  48.6  220  14  7  10.5   5.8
  8000   8.6  47.5  220  15  8   6.7   3.7 |  10.0  50.0  220  14  7  10.1   5.6
  7750   9.0  48.2  215  15  8   5.2   2.8 |  10.7  51.3  220  14  7   9.6   5.3
  7500   9.4  48.9  210  14  7   5.2   2.9 |  11.5  52.7  220  14  7   9.9   5.5
  7250   9.8  49.6  205  15  8   5.3   2.9 |  12.2  54.0  220  13  7  10.5   5.8
  7000  10.2  50.4  195  15  8   4.7   2.6 |  13.0  55.4  220  13  7  10.1   5.5
  6750  10.5  50.9  190  15  8   3.5   1.9 |  13.7  56.7  220  13  7   9.0   5.0
  6500  10.8  51.4  185  15  8   2.6   1.4 |  14.4  57.9  220  13  7  10.4   5.7
  6250  11.0  51.8  180  13  7   2.2   1.2 |  15.3  59.5  220  12  6  12.1   6.7
  6000  11.1  52.0  175  12  6   2.6   1.4 |  16.2  61.2  220  12  6  10.5   5.7
  5750  11.4  52.5  170  10  5   6.6   3.6 |  16.9  62.4  220  11  6  11.6   6.4
  5500  12.1  53.8  170   9  5  10.5   5.8 |  18.0  64.4  225  11  6  15.9   8.7
  5250  12.9  55.2  170   9  4   9.1   5.0 |  19.2  66.6  225  11  6  16.8   9.2
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/18/2017 at 1500 MDT          |       04/18/2017 at 1800 MDT
                                           |
K index... +18.2  LI... +1.3               | K index... +18.5  LI... +0.3
CAPE... +1.3  CIN... -0.4                  | CAPE... +4.2  CIN... -1.4
                                           |
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 -64.3 -83.7  270  40 21   3.0   1.7 | -64.2 -83.6  255  44 23   3.4   1.9
 45000 -59.3 -74.7  265  63 32   4.0   2.2 | -58.6 -73.5  260  70 36   4.5   2.5
 40000 -53.2 -63.8  265  91 47   4.1   2.3 | -51.8 -61.2  260  92 47   4.6   2.5
 38000 -51.5 -60.7  265  88 45   2.8   1.5 | -50.3 -58.5  255  91 47   2.2   1.2
 36000 -49.8 -57.6  260  83 43   2.8   1.5 | -49.0 -56.2  255  89 46   2.2   1.2
 34000 -46.8 -52.2  255  80 41   7.8   4.3 | -46.7 -52.1  250  87 45   6.2   3.4
 32000 -42.1 -43.8  255  78 40   7.8   4.3 | -43.0 -45.4  250  85 44   6.1   3.4
 30000 -37.0 -34.6  255  71 37   7.3   4.0 | -38.4 -37.1  250  80 41   7.8   4.3
 29000 -34.9 -30.8  255  66 34   7.3   4.0 | -36.0 -32.8  255  76 39   7.8   4.3
 28000 -32.7 -26.9  255  61 31   7.3   4.0 | -33.7 -28.7  255  73 38   7.8   4.3
 27000 -30.4 -22.7  255  56 29   7.9   4.3 | -31.4 -24.5  255  67 34   7.7   4.2
 26000 -28.0 -18.4  250  51 26   7.9   4.3 | -29.1 -20.4  255  57 29   7.7   4.2
 25000 -25.6 -14.1  245  47 24   7.9   4.3 | -26.7 -16.1  250  48 24   7.7   4.2
 24000 -23.3  -9.9  240  46 24   6.9   3.8 | -24.5 -12.1  245  42 21   6.9   3.8
 23000 -21.2  -6.2  240  49 25   7.0   3.8 | -22.4  -8.3  245  45 23   7.0   3.9
 22000 -19.1  -2.4  235  52 27   7.0   3.8 | -20.2  -4.4  245  48 25   7.0   3.8
 21000 -17.1   1.2  240  52 27   6.2   3.4 | -18.3  -0.9  245  49 25   5.5   3.0
 20000 -15.3   4.5  240  50 26   6.2   3.4 | -16.7   1.9  245  47 24   5.6   3.1
 19500 -14.3   6.3  240  49 25   6.2   3.4 | -15.8   3.6  245  46 24   5.6   3.1
 19000 -13.4   7.9  240  49 25   6.3   3.5 | -15.0   5.0  245  45 23   5.5   3.0
 18500 -12.5   9.5  240  47 24   5.3   2.9 | -14.1   6.6  245  43 22   7.0   3.8
 18000 -11.7  10.9  240  46 24   5.4   3.0 | -13.1   8.4  240  42 22   6.9   3.8
 17500 -10.9  12.4  240  44 23   5.7   3.1 | -12.1  10.2  240  40 21   7.2   3.9
 17000 -10.1  13.8  240  44 22   6.0   3.3 | -11.0  12.2  235  39 20   7.5   4.1
 16500  -9.2  15.4  240  43 22   6.1   3.3 | -10.0  14.0  235  38 19   7.7   4.2
 16000  -8.3  17.1  240  42 22   6.4   3.5 |  -8.7  16.3  230  36 19   9.6   5.2
 15500  -7.4  18.7  240  40 21   6.4   3.5 |  -7.3  18.9  230  35 18   9.4   5.2
 15000  -5.9  21.4  235  37 19   8.0   4.4 |  -5.9  21.4  230  34 18   9.5   5.2
 14500  -4.8  23.4  235  34 18   8.1   4.5 |  -3.8  25.2  225  32 17   9.5   5.2
 14000  -3.5  25.7  230  32 16   9.2   5.0 |  -2.4  27.7  225  31 16   9.3   5.1
 13500  -2.2  28.0  225  29 15   9.2   5.0 |  -1.0  30.2  225  31 16   9.4   5.1
 13000  -0.9  30.4  225  27 14   8.8   4.8 |   0.3  32.5  225  30 15   9.2   5.0
 12500   0.4  32.7  220  25 13   8.8   4.8 |   1.7  35.1  225  29 15   9.2   5.0
 12000   1.7  35.1  220  22 12   9.1   5.0 |   3.1  37.6  225  27 14   9.2   5.0
 11500   3.1  37.6  220  20 11   9.2   5.0 |   4.4  39.9  225  26 14   9.2   5.0
 11000   4.4  39.9  225  19 10   8.0   4.4 |   5.8  42.4  230  25 13   8.8   4.8
 10500   5.6  42.1  225  18  9   9.0   5.0 |   7.1  44.8  230  24 12   9.4   5.2
 10250   6.4  43.5  225  17  9  11.9   6.6 |   7.8  46.0  230  23 12  11.1   6.1
 10000   7.3  45.1  230  17  9  10.9   6.0 |   8.7  47.7  230  23 12   9.9   5.4
  9750   8.0  46.4  230  17  9   9.3   5.1 |   9.3  48.7  235  22 11   8.9   4.9
  9500   8.7  47.7  230  16  8   9.8   5.4 |  10.0  50.0  235  21 11   8.9   4.9
  9250   9.4  48.9  230  16  8   9.5   5.2 |  10.7  51.3  235  21 11   9.8   5.4
  9000  10.1  50.2  230  16  8   9.8   5.4 |  11.5  52.7  235  20 10  10.2   5.6
  8750  10.9  51.6  230  16  8  10.2   5.6 |  12.2  54.0  240  20 10   9.5   5.2
  8500  11.7  53.1  230  16  8  10.0   5.5 |  12.9  55.2  240  19 10   9.6   5.3
  8250  12.4  54.3  230  15  8  10.9   6.0 |  13.6  56.5  240  19 10  10.0   5.5
  8000  13.3  55.9  235  15  8  10.3   5.6 |  14.4  57.9  240  19 10   9.7   5.3
  7750  13.9  57.0  235  15  8   9.0   4.9 |  15.1  59.2  240  18  9   9.0   4.9
  7500  14.6  58.3  235  15  8   9.6   5.3 |  15.8  60.4  245  18  9   9.2   5.1
  7250  15.4  59.7  235  15  8  10.5   5.7 |  16.5  61.7  245  18  9  10.8   5.9
  7000  16.2  61.2  235  14  7  10.4   5.7 |  17.3  63.1  245  17  9  10.8   5.9
  6750  16.9  62.4  235  14  7   9.1   5.0 |  18.1  64.6  245  17  9   9.0   4.9
  6500  17.6  63.7  235  14  7  10.6   5.8 |  18.7  65.7  245  17  8   9.6   5.3
  6250  18.5  65.3  235  13  7  12.6   6.9 |  19.5  67.1  245  16  8  10.8   6.0
  6000  19.4  66.9  235  13  7  11.4   6.3 |  20.3  68.5  245  15  8  10.7   5.9
  5750  20.2  68.4  240  12  6  11.1   6.1 |  21.1  70.0  245  14  7  10.0   5.5
  5500  21.2  70.2  240  12  6  14.7   8.1 |  21.8  71.2  245  13  7   9.3   5.1
  5250  22.4  72.3  240  12  6  18.8  10.3 |  22.5  72.5  245  13  7   9.0   5.0
  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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