Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 171233
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0633 MDT Thursday, May 17, 2018

This forecast is for Thursday, May 17, 2018:

If the trigger temperature of 76.9 F/24.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1646 ft/min (8.4 m/s)
   Maximum height of thermals.................. 21455 ft MSL (16616 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1115 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................. 13740 ft MSL (8901 ft AGL)
Thermal soaring outlook for Friday 05/18....... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:59:28 / 20:21:26 MDT
Total possible sunshine........... 14 hr 21 min 59 sec (861 min 59 sec)
Altitude of sun at 13:10:39 MDT... 70.32 degrees

Upper air data from rawinsonde observation taken on 05/17/2018 at 0600 MDT

Freezing level.................. 13551 ft MSL (8712 ft AGL)
Convective condensation level... 21144 ft MSL (16305 ft AGL)
Lifted condensation level....... 21398 ft MSL (16558 ft AGL)
Lifted index.................... +0.6
K index......................... +4.6

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  -58.8 -73.8   235   30   16  -0.6  -0.3  100.3 212.6    40.7      M    M
 45000  -56.6 -69.9   240   40   21  -1.0  -0.5   79.3 174.8    30.6      M    M
 40000  -55.5 -67.9   245   57   30  -0.1  -0.1   58.1 136.6    18.8      M    M
 38000  -57.1 -70.8   240   66   34   0.9   0.5   45.8 114.5    11.1      M    M
 36000  -54.2 -65.6   235   62   32   6.8   3.8   41.3 106.3     8.3      M    M
 34000  -49.8 -57.6   235   58   30   8.5   4.7   39.4 102.8     7.1      M    M
 32000  -44.6 -48.3   230   55   29   8.5   4.7   38.3 100.9     6.5      M    M
 30000  -39.6 -39.3   225   53   27   8.3   4.6   37.4  99.4     6.0      M    M
 29000  -37.1 -34.8   220   51   26   8.3   4.6   36.8  98.2     5.6      M    M
 28000  -34.6 -30.3   220   49   25   8.3   4.6   36.2  97.2     5.2      M    M
 27000  -32.3 -26.1   215   47   24   7.3   4.0   35.3  95.5     4.5      M    M
 26000  -30.1 -22.2   215   46   23   7.3   4.0   34.3  93.8     3.8      M    M
 25000  -28.0 -18.4   210   44   23   7.3   4.0   33.5  92.3     3.2      M    M
 24000  -25.6 -14.1   215   41   21   8.5   4.7   32.8  91.0     2.7      M    M
 23000  -23.5 -10.3   210   41   21   8.3   4.5   31.7  89.1     1.8      M    M
 22000  -22.1  -7.8   205   41   21   7.6   4.2   29.9  85.8     0.3      M    M
 21000  -19.6  -3.3   205   41   21   8.3   4.6   29.4  84.8    -0.1   1610  8.2
 20000  -16.8   1.8   200   40   21   7.0   3.9   28.4  83.1    -1.0   1489  7.6
 19500  -15.7   3.7   200   37   19   8.5   4.6   28.0  82.5    -1.4   1440  7.3
 19000  -14.5   5.9   200   34   17   8.7   4.8   27.8  82.0    -1.6   1389  7.1
 18500  -13.2   8.2   200   32   17   8.9   4.9   27.7  81.8    -1.8   1334  6.8
 18000  -11.8  10.8   200   30   16   9.0   4.9   27.5  81.6    -1.9   1279  6.5
 17500  -10.5  13.1   205   29   15   9.0   4.9   27.4  81.4    -2.0   1224  6.2
 17000   -9.1  15.6   205   26   14   9.0   4.9   27.3  81.2    -2.1   1169  5.9
 16500   -7.8  18.0   200   22   11   9.0   4.9   27.2  80.9    -2.2   1114  5.7
 16000   -6.5  20.3   190   18   10   9.0   4.9   27.1  80.7    -2.4   1059  5.4
 15500   -5.1  22.8   200   15    8   9.0   4.9   26.9  80.4    -2.5   1004  5.1
 15000   -3.8  25.2   210   12    6   8.9   4.9   26.8  80.2    -2.7    949  4.8
 14500   -2.4  27.7   215   14    7   8.9   4.9   26.6  79.9    -2.8    894  4.5
 14000   -1.1  30.0   220   15    8   8.9   4.9   26.5  79.7    -2.9    839  4.3
 13500    0.2  32.4   220   15    8   8.9   4.9   26.4  79.4    -3.1    785  4.0
 13000    1.6  34.9   225   15    8   8.9   4.9   26.2  79.2    -3.2    730  3.7
 12500    2.9  37.2   225   16    8   8.9   4.9   26.1  78.9    -3.4    675  3.4
 12000    4.2  39.6   225   16    8   8.9   4.9   26.0  78.8    -3.5    620  3.2
 11500    5.5  41.9   225   14    7   8.9   4.9   25.8  78.4    -3.7    566  2.9
 11000    6.9  44.4   230   12    6   8.9   4.9   25.6  78.1    -3.9    511  2.6
 10500    8.2  46.8   230   10    5   8.8   4.8   25.5  77.8    -4.0    456  2.3
 10250    8.9  48.0   235    9    5   9.0   4.9   25.4  77.7    -4.1    429  2.2
 10000    9.6  49.3   235   10    5   9.3   5.1   25.4  77.6    -4.2    401  2.0
  9750   10.3  50.5   240   11    5   9.4   5.2   25.3  77.6    -4.2    373  1.9
  9500   11.0  51.8   240   12    6   9.4   5.1   25.3  77.5    -4.2    344  1.7
  9250   11.7  53.1   245   13    7   9.4   5.2   25.3  77.5    -4.3    316  1.6
  9000   12.4  54.3   245   14    7   9.4   5.1   25.3  77.5    -4.3    287  1.5
  8750   13.1  55.6   245   14    7   9.4   5.2   25.2  77.4    -4.4    259  1.3
  8500   13.8  56.8   245   14    7   9.2   5.0   25.2  77.3    -4.4    230  1.2
  8250   14.5  58.1   250   14    7  10.3   5.6   25.1  77.3    -4.5    202  1.0
  8000   15.2  59.4   250   14    7   6.1   3.4   25.1  77.2    -4.5    173  0.9
  7750   15.4  59.7   245   12    6   0.9   0.5   24.6  76.2    -5.0    160  0.8
  7500   15.5  59.9   235    9    5   4.3   2.4   24.0  75.1    -5.6    148  0.8
  7250   16.0  60.8   220    7    4   8.5   4.7   23.7  74.7    -5.9    125  0.6
  7000   16.8  62.2   195    6    3  11.1   6.1   23.7  74.7    -5.9     96  0.5
  6750   17.5  63.5   175    7    4   5.8   3.2   23.7  74.7    -5.9     67  0.3
  6500   17.6  63.7   165   10    5  -0.3  -0.2   23.1  73.6    -6.5     56  0.3
  6250   17.6  63.7   155   12    6   0.6   0.3   22.4  72.3    -7.3     49  0.2
  6000   17.6  63.7   150   15    8  -1.0  -0.6   21.6  71.0    -8.0     41  0.2
  5750   17.6  63.7   145   14    7   4.7   2.6   20.9  69.7    -8.8     34  0.2
  5500   17.6  63.7   140   10    5 -16.5  -9.1   20.2  68.4    -9.5     26  0.1
  5250   15.2  59.4   125    8    4 -31.6 -17.3   17.1  62.8   -12.7     91  0.5
  5000   14.2  57.6   095    6    3   7.8   4.3   15.3  59.6   -14.5    115  0.6

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

           05/17/2018 at 0900 MDT          |       05/17/2018 at 1200 MDT
                                           |
K index... +11.6  LI... +2.3               | K index... +15.4  LI... +1.6
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 -57.5 -71.5  250  34 17   2.6   1.4 | -57.4 -71.3  250  31 16   2.7   1.5
 45000 -54.0 -65.2  250  43 22  -0.1  -0.1 | -53.8 -64.8  250  43 22  -0.4  -0.2
 40000 -54.2 -65.6  250  53 27  -0.2  -0.1 | -54.5 -66.1  240  52 27  -0.4  -0.2
 38000 -53.5 -64.3  245  57 29   1.6   0.9 | -53.6 -64.5  240  56 29   1.9   1.1
 36000 -52.6 -62.7  240  62 32   1.6   0.9 | -52.5 -62.5  240  61 31   1.9   1.1
 34000 -50.2 -58.4  235  64 33   7.8   4.3 | -49.9 -57.8  235  63 32   7.9   4.3
 32000 -45.6 -50.1  235  61 31   7.7   4.2 | -45.2 -49.4  235  60 31   7.8   4.3
 30000 -40.9 -41.6  230  57 29   7.9   4.3 | -40.5 -40.9  230  56 29   8.1   4.5
 29000 -38.5 -37.3  230  55 28   7.9   4.3 | -38.0 -36.4  230  52 27   8.1   4.5
 28000 -35.6 -32.1  225  53 27   7.9   4.3 | -35.0 -31.0  230  47 24   8.1   4.5
 27000 -33.1 -27.6  225  51 26   8.2   4.5 | -32.7 -26.9  230  44 23   7.4   4.1
 26000 -30.7 -23.3  225  49 25   8.3   4.5 | -30.4 -22.7  230  44 22   7.4   4.0
 25000 -28.2 -18.8  225  47 24   8.3   4.5 | -28.2 -18.8  225  43 22   7.4   4.0
 24000 -25.8 -14.4  220  45 23   7.5   4.1 | -26.0 -14.8  225  42 21   7.5   4.1
 23000 -23.5 -10.3  225  43 22   7.6   4.2 | -23.8 -10.8  230  41 21   7.5   4.1
 22000 -21.3  -6.3  225  40 21   7.6   4.2 | -21.6  -6.9  230  40 21   7.5   4.1
 21000 -19.0  -2.2  225  38 20   7.6   4.2 | -19.3  -2.7  230  38 19   7.4   4.1
 20000 -16.7   1.9  225  36 19   7.6   4.2 | -17.1   1.2  230  34 18   7.4   4.1
 19500 -15.6   3.9  225  35 18   7.6   4.2 | -16.0   3.2  230  32 17   7.4   4.1
 19000 -14.5   5.9  225  34 17   7.6   4.1 | -14.9   5.2  230  30 16   7.4   4.1
 18500 -13.4   7.9  225  33 17   7.1   3.9 | -13.9   7.0  230  28 14   6.5   3.6
 18000 -12.4   9.7  225  31 16   7.2   3.9 | -12.9   8.8  230  26 13   6.6   3.6
 17500 -11.3  11.7  220  30 15   7.1   3.9 | -12.0  10.4  230  24 12   7.3   4.0
 17000 -10.3  13.5  220  28 14   7.1   3.9 | -10.9  12.4  225  21 11   7.6   4.2
 16500  -9.3  15.3  220  26 14   7.4   4.1 |  -9.8  14.4  225  19 10   7.9   4.3
 16000  -8.1  17.4  220  24 12   8.7   4.8 |  -8.6  16.5  220  18  9   8.9   4.9
 15500  -6.8  19.8  220  22 11   8.6   4.7 |  -7.3  18.9  220  17  9   8.8   4.8
 15000  -5.5  22.1  220  20 10   9.6   5.2 |  -5.9  21.4  215  16  8   9.6   5.3
 14500  -4.1  24.6  220  18  9   9.5   5.2 |  -4.5  23.9  215  15  8   9.6   5.3
 14000  -2.7  27.1  220  17  9   9.3   5.1 |  -3.0  26.6  210  15  8   9.6   5.2
 13500  -0.6  30.9  215  15  8   9.2   5.1 |  -0.9  30.4  210  14  7   9.6   5.3
 13000   0.7  33.3  215  14  7   8.7   4.8 |   0.5  32.9  205  13  7   9.2   5.0
 12500   2.0  35.6  220  12  6   8.8   4.8 |   1.9  35.4  205  12  6   9.2   5.1
 12000   3.3  37.9  220  11  6   8.5   4.7 |   3.3  37.9  205  11  6   9.1   5.0
 11500   4.6  40.3  225  10  5   8.6   4.7 |   4.6  40.3  205  11  6   9.3   5.1
 11000   5.8  42.4  225   9  5   7.4   4.1 |   5.9  42.6  205  10  5   7.6   4.2
 10500   6.9  44.4  225   9  4   7.8   4.3 |   7.0  44.6  200   9  5   8.8   4.8
 10250   7.6  45.7  225   8  4   9.7   5.3 |   7.8  46.0  200   9  5  10.4   5.7
 10000   8.3  46.9  225   8  4   8.6   4.7 |   8.5  47.3  200   9  4   8.7   4.8
  9750   8.8  47.8  225   8  4   6.8   3.7 |   9.1  48.4  200   8  4   7.9   4.3
  9500   9.4  48.9  225   7  4   7.6   4.1 |   9.7  49.5  200   8  4   8.2   4.5
  9250   9.9  49.8  220   7  4   6.2   3.4 |  10.3  50.5  200   7  4   7.8   4.3
  9000  10.3  50.5  220   7  3   5.2   2.8 |  10.9  51.6  200   7  3   8.1   4.5
  8750  10.8  51.4  215   6  3   5.7   3.1 |  11.5  52.7  205   6  3   8.7   4.8
  8500  11.2  52.2  215   6  3   5.4   3.0 |  12.2  54.0  205   6  3   8.5   4.7
  8250  11.6  52.9  210   6  3   6.5   3.6 |  12.8  55.0  205   5  3   9.5   5.2
  8000  12.1  53.8  210   5  3   5.5   3.0 |  13.6  56.5  205   5  3   9.9   5.4
  7750  12.4  54.3  210   5  2   3.9   2.1 |  14.3  57.7  205   5  3   9.4   5.1
  7500  12.8  55.0  210   5  2   4.3   2.3 |  15.0  59.0  210   5  3   9.7   5.3
  7250  13.1  55.6  205   4  2   4.0   2.2 |  15.8  60.4  210   5  3  10.4   5.7
  7000  13.4  56.1  200   5  2   4.3   2.3 |  16.6  61.9  210   5  3  10.4   5.7
  6750  13.7  56.7  200   5  2   3.9   2.1 |  17.3  63.1  210   5  3   9.6   5.3
  6500  14.0  57.2  195   5  2   6.0   3.3 |  18.0  64.4  215   5  3  10.6   5.8
  6250  14.6  58.3  190   5  2   8.1   4.4 |  18.9  66.0  215   5  2  11.8   6.5
  6000  15.1  59.2  185   5  2   7.9   4.4 |  19.7  67.5  215   5  2  11.1   6.1
  5750  15.7  60.3  185   5  2   9.5   5.2 |  20.6  69.1  215   5  2  11.4   6.3
  5500  16.5  61.7  185   4  2  11.0   6.0 |  21.5  70.7  215   5  2  15.3   8.4
  5250  17.3  63.1  185   4  2  11.1   6.1 |  22.8  73.0  220   5  2  19.3  10.6
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/17/2018 at 1500 MDT          |       05/17/2018 at 1800 MDT
                                           |
K index... +16.4  LI... +1.0               | K index... +15.7  LI... +1.4
CAPE... 0.0  CIN... -1.1                   | 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  245  29 15   1.9   1.0 | -57.0 -70.6  250  27 14   2.2   1.2
 45000 -54.4 -65.9  250  42 22  -0.1  -0.0 | -53.9 -65.0  250  37 19   0.0   0.0
 40000 -54.5 -66.1  240  50 26  -0.0  -0.0 | -53.9 -65.0  245  45 23   0.1   0.0
 38000 -53.6 -64.5  240  53 27   1.9   1.0 | -53.1 -63.6  240  47 24   1.8   1.0
 36000 -52.5 -62.5  235  56 29   1.9   1.0 | -52.0 -61.6  235  49 25   1.8   1.0
 34000 -50.0 -58.0  235  58 30   7.6   4.2 | -49.8 -57.6  235  50 26   6.9   3.8
 32000 -45.5 -49.9  235  57 29   7.5   4.1 | -45.7 -50.3  230  50 26   6.9   3.8
 30000 -40.8 -41.4  230  54 28   8.5   4.7 | -41.3 -42.3  230  49 25   8.5   4.6
 29000 -37.6 -35.7  230  51 26   8.5   4.7 | -38.1 -36.6  230  47 24   8.5   4.6
 28000 -35.0 -31.0  230  49 25   8.5   4.7 | -35.6 -32.1  230  45 23   8.4   4.6
 27000 -32.6 -26.7  230  46 24   7.6   4.2 | -33.2 -27.8  230  42 22   7.3   4.0
 26000 -30.3 -22.5  230  43 22   7.6   4.1 | -31.0 -23.8  230  40 20   7.4   4.0
 25000 -28.1 -18.6  230  40 21   7.6   4.2 | -28.8 -19.8  230  37 19   7.4   4.0
 24000 -25.9 -14.6  230  38 20   6.3   3.5 | -26.6 -15.9  230  34 17   7.6   4.2
 23000 -24.0 -11.2  230  36 18   6.5   3.6 | -24.3 -11.7  230  30 15   7.6   4.2
 22000 -22.1  -7.8  230  34 17   6.6   3.6 | -22.1  -7.8  225  26 14   7.7   4.2
 21000 -19.9  -3.8  225  31 16   8.6   4.7 | -19.7  -3.5  225  23 12   8.7   4.8
 20000 -17.4   0.7  220  26 14   8.6   4.7 | -17.1   1.2  220  22 11   8.7   4.8
 19500 -16.2   2.8  220  24 13   8.6   4.7 | -15.8   3.6  215  21 11   8.7   4.8
 19000 -14.9   5.2  215  22 12   8.6   4.7 | -14.6   5.7  215  20 10   8.8   4.8
 18500 -13.7   7.3  210  22 11   8.1   4.5 | -13.4   7.9  215  19 10   7.6   4.2
 18000 -12.5   9.5  210  21 11   8.2   4.5 | -12.2  10.0  210  19 10   7.7   4.2
 17500 -11.3  11.7  210  21 11   8.2   4.5 | -11.1  12.0  210  19 10   8.3   4.5
 17000 -10.0  14.0  205  21 11   8.2   4.5 |  -9.8  14.4  210  19 10   8.6   4.7
 16500  -8.8  16.2  205  20 11   8.4   4.6 |  -8.5  16.7  210  19 10   8.7   4.8
 16000  -7.5  18.5  205  20 10   9.4   5.1 |  -7.2  19.0  210  19 10   9.1   5.0
 15500  -6.1  21.0  205  20 10   9.3   5.1 |  -5.8  21.6  210  19 10   9.0   4.9
 15000  -4.7  23.5  200  19 10   9.2   5.0 |  -4.4  24.1  210  18  9   9.5   5.2
 14500  -3.3  26.1  200  18 10   9.2   5.1 |  -3.0  26.6  210  18  9   9.5   5.2
 14000  -1.3  29.7  200  17  9   8.8   4.8 |  -0.9  30.4  210  17  9   9.4   5.1
 13500   0.0  32.0  200  16  8   8.8   4.8 |   0.5  32.9  215  16  8   9.4   5.1
 13000   1.3  34.3  200  15  8   8.5   4.7 |   1.9  35.4  215  15  8   9.5   5.2
 12500   2.6  36.7  195  14  7   8.5   4.7 |   3.3  37.9  215  15  7   9.5   5.2
 12000   3.9  39.0  195  12  6   8.5   4.7 |   4.7  40.5  215  14  7   9.0   5.0
 11500   5.2  41.4  200  10  5   8.6   4.7 |   6.1  43.0  220  13  7   9.1   5.0
 11000   6.3  43.3  205   8  4   7.3   4.0 |   7.4  45.3  220  12  6   8.0   4.4
 10500   7.4  45.3  215   7  3   8.1   4.4 |   8.5  47.3  225  11  5   8.1   4.5
 10250   8.1  46.6  220   6  3  10.2   5.6 |   9.2  48.6  225  10  5   9.2   5.0
 10000   8.9  48.0  225   6  3   9.6   5.3 |   9.9  49.8  230  10  5   9.0   4.9
  9750   9.5  49.1  230   6  3   8.9   4.9 |  10.5  50.9  230   9  4   8.5   4.7
  9500  10.2  50.4  235   6  3   9.0   5.0 |  11.2  52.2  235   8  4   8.8   4.8
  9250  10.9  51.6  240   6  3   9.1   5.0 |  11.8  53.2  240   7  4   8.0   4.4
  9000  11.6  52.9  245   6  3   9.6   5.3 |  12.4  54.3  245   7  4   7.6   4.1
  8750  12.3  54.1  245   6  3   9.9   5.5 |  13.0  55.4  250   6  3   8.1   4.4
  8500  13.1  55.6  245   6  3   9.6   5.3 |  13.6  56.5  255   6  3   7.9   4.3
  8250  13.8  56.8  250   6  3  11.2   6.1 |  14.2  57.6  260   6  3   8.0   4.4
  8000  14.7  58.5  250   6  3  10.9   6.0 |  14.8  58.6  265   6  3   7.6   4.2
  7750  15.4  59.7  250   6  3   9.1   5.0 |  15.3  59.5  270   6  3   7.2   4.0
  7500  16.1  61.0  255   6  3   9.7   5.3 |  15.8  60.4  270   6  3   7.3   4.0
  7250  16.8  62.2  255   6  3  10.4   5.7 |  16.4  61.5  275   6  3   8.5   4.7
  7000  17.6  63.7  255   7  3  10.3   5.7 |  17.1  62.8  275   6  3   9.4   5.2
  6750  18.4  65.1  255   7  3   9.1   5.0 |  17.8  64.0  275   6  3   9.1   5.0
  6500  19.1  66.4  255   7  3  10.2   5.6 |  18.5  65.3  275   6  3   9.6   5.3
  6250  19.9  67.8  260   7  3  11.8   6.5 |  19.2  66.6  275   6  3  10.5   5.7
  6000  20.8  69.4  260   7  3  11.6   6.4 |  20.0  68.0  275   6  3  10.7   5.8
  5750  21.6  70.9  260   7  3  11.5   6.3 |  20.8  69.4  275   6  3  10.9   6.0
  5500  22.6  72.7  260   7  3  14.3   7.9 |  21.6  70.9  270   6  3   9.4   5.2
  5250  23.8  74.8  260   7  4  18.6  10.2 |  22.2  72.0  270   6  3   6.4   3.5
  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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