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281
UXUS97 KGJT 211238
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0638 MDT Monday, July 21, 2014

This forecast is for Monday, July 21, 2014:

If the trigger temperature of 88.7 F/31.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1248 ft/min (6.3 m/s)
   Maximum height of thermals.................. 18033 ft MSL (13194 ft AGL)

Forecast maximum temperature................... 96.0 F/36.0 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................. 11208 ft MSL (6368 ft AGL)
Thermal soaring outlook for Tuesday 07/22...... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:05:17 / 20:35:59 MDT
Total possible sunshine........... 14 hr 30 min 42 sec (870 min 42 sec)
Altitude of sun at 13:20:31 MDT... 71.22 degrees

Upper air data from rawinsonde observation taken on 07/21/2014 at 0600 MDT

Freezing level.................. 16293 ft MSL (11454 ft AGL)
Convective condensation level... 17679 ft MSL (12840 ft AGL)
Lifted condensation level....... 17987 ft MSL (13147 ft AGL)
Lifted index.................... -3.4
K index......................... +21.0

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -66.3 -87.3   235   16    8  -3.2  -1.8   83.5 182.3    27.8      M    M
 45000  -61.9 -79.4   245   58   30   6.0   3.3   66.1 151.0    19.1      M    M
 40000  -51.1 -60.0   235   83   43   7.9   4.3   59.3 138.8    15.9      M    M
 38000  -46.7 -52.1   235   68   35   6.1   3.3   57.0 134.6    14.7      M    M
 36000  -43.1 -45.6   230   54   28   6.9   3.8   53.9 129.0    12.9      M    M
 34000  -38.1 -36.6   230   49   25   8.4   4.6   52.6 126.8    12.3      M    M
 32000  -33.1 -27.6   235   47   24   8.4   4.6   51.6 124.9    11.9      M    M
 30000  -27.9 -18.2   230   48   25   7.0   3.8   49.8 121.7    10.9      M    M
 29000  -26.3 -15.3   225   44   23   3.8   2.1   48.0 118.5     9.6      M    M
 28000  -25.2 -13.4   220   40   21   3.8   2.1   45.7 114.3     7.9      M    M
 27000  -23.7 -10.7   225   38   20   7.8   4.3   43.9 111.1     6.6      M    M
 26000  -21.4  -6.5   230   36   19   7.5   4.1   43.1 109.5     6.0      M    M
 25000  -20.1  -4.2   235   36   18  -1.6  -0.9   41.1 106.0     4.5      M    M
 24000  -19.2  -2.6   250   33   17   9.8   5.4   38.6 101.5     2.5      M    M
 23000  -16.5   2.3   245   31   16  10.1   5.6   38.5 101.3     2.3      M    M
 22000  -14.7   5.5   245   29   15   9.3   5.1   37.2  98.9     1.2      M    M
 21000  -12.0  10.4   240   28   14   9.1   5.0   36.9  98.5     1.0      M    M
 20000   -9.3  15.3   235   26   13   8.1   4.4   36.7  98.0     0.8      M    M
 19500   -8.1  17.4   230   26   13   8.1   4.4   36.4  97.5     0.6      M    M
 19000   -6.9  19.6   230   26   13   8.5   4.7   36.1  97.0     0.3      M    M
 18500   -5.6  21.9   235   25   13   9.4   5.2   36.0  96.8     0.1      M    M
 18000   -4.2  24.4   240   25   13   8.0   4.4   36.0  96.7     0.1      M    M
 17500   -3.3  26.1   240   24   12   6.0   3.3   35.4  95.7    -0.5   1212  6.2
 17000   -2.1  28.2   235   23   12   9.4   5.2   35.0  95.1    -0.8   1163  5.9
 16500   -0.2  31.6   230   21   11   7.4   4.1   34.8  94.6    -1.0   1082  5.5
 16000    0.8  33.4   225   20   10   7.3   4.0   34.4  93.9    -1.5   1037  5.3
 15500    1.9  35.4   210   21   11   7.4   4.1   34.0  93.1    -1.9    992  5.0
 15000    2.9  37.2   205   22   12   7.7   4.2   33.6  92.5    -2.4    947  4.8
 14500    4.1  39.4   205   19   10   9.5   5.2   33.4  92.2    -2.6    894  4.5
 14000    5.5  41.9   210   16    8   9.4   5.2   33.4  92.2    -2.6    837  4.3
 13500    6.9  44.4   215   14    7   9.4   5.2   33.4  92.1    -2.7    780  4.0
 13000    8.3  46.9   215   13    7   9.4   5.2   33.3  92.0    -2.7    724  3.7
 12500    9.7  49.5   220   15    8   9.4   5.2   33.3  91.9    -2.8    667  3.4
 12000   11.1  52.0   225   17    9   9.4   5.2   33.2  91.8    -2.9    610  3.1
 11500   12.5  54.5   235   20   10   9.4   5.2   33.1  91.7    -3.0    554  2.8
 11000   13.9  57.0   245   23   12   9.4   5.1   33.1  91.6    -3.0    497  2.5
 10500   15.3  59.5   245   21   11   8.9   4.9   33.0  91.4    -3.1    440  2.2
 10250   16.0  60.8   245   20   10   8.3   4.5   32.9  91.2    -3.2    414  2.1
 10000   16.6  61.9   245   19   10   8.4   4.6   32.8  91.0    -3.4    388  2.0
  9750   17.2  63.0   245   19   10   8.3   4.6   32.7  90.8    -3.5    362  1.8
  9500   17.8  64.0   250   18    9   8.3   4.6   32.6  90.6    -3.6    336  1.7
  9250   18.5  65.3   250   17    9   8.4   4.6   32.5  90.4    -3.7    310  1.6
  9000   19.1  66.4   250   16    8   8.2   4.5   32.4  90.3    -3.8    284  1.4
  8750   19.7  67.5   245   14    7   8.8   4.8   32.3  90.1    -3.9    258  1.3
  8500   20.3  68.5   235   12    6   6.5   3.6   32.1  89.9    -4.0    232  1.2
  8250   20.6  69.1   220   11    6   3.8   2.1   31.7  89.1    -4.5    215  1.1
  8000   20.9  69.6   205   10    5   4.1   2.3   31.3  88.4    -5.0    201  1.0
  7750   21.1  70.0   185   11    6   4.2   2.3   30.9  87.6    -5.5    186  0.9
  7500   21.4  70.5   170   13    7   4.0   2.2   30.4  86.8    -6.0    171  0.9
  7250   21.6  70.9   160   15    8   4.8   2.6   30.0  86.0    -6.5    156  0.8
  7000   21.9  71.4   150   18    9   2.2   1.2   29.6  85.3    -6.9    141  0.7
  6750   21.5  70.7   145   20   10 -15.4  -8.4   28.5  83.3    -8.1    146  0.7
  6500   20.2  68.4   145   21   11  -5.4  -2.9   26.5  79.6   -10.1    176  0.9
  6250   20.8  69.4   140   22   11  12.4   6.8   26.4  79.5   -10.2    150  0.8
  6000   21.5  70.7   135   24   12   7.8   4.3   26.3  79.4   -10.3    124  0.6
  5750   22.1  71.8   135   22   11   9.3   5.1   26.2  79.2   -10.5     98  0.5
  5500   22.7  72.9   130   19   10   8.0   4.4   26.2  79.1   -10.6     72  0.4
  5250   23.3  73.9   125   16    8  11.8   6.5   26.1  79.0   -10.7     45  0.2
  5000   24.0  75.2   120   13    7  -2.2  -1.2   26.0  78.9   -10.8     19  0.1

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

           07/21/2014 at 0900 MDT          |       07/21/2014 at 1200 MDT
                                           |
K index... +24.7  LI... +0.4               | K index... +25.9  LI... +0.2
CAPE... 0.0  CIN... -3.5                   | CAPE... +27.6  CIN... -74.4
                                           |
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 -65.1 -85.2  235  31 16   2.0   1.1 | -64.9 -84.8  235  27 14   1.8   1.0
 45000 -60.4 -76.7  240  50 25   5.5   3.0 | -60.2 -76.4  235  46 23   5.9   3.2
 40000 -51.8 -61.2  235  76 39   7.5   4.1 | -50.6 -59.1  240  68 35   7.0   3.9
 38000 -46.7 -52.1  230  75 38   7.6   4.2 | -46.4 -51.5  235  65 34   7.0   3.8
 36000 -42.1 -43.8  230  74 38   7.3   4.0 | -42.2 -44.0  230  63 33   6.9   3.8
 34000 -37.9 -36.2  230  62 32   7.0   3.9 | -38.1 -36.6  230  57 29   6.8   3.7
 32000 -33.7 -28.7  230  49 25   7.1   3.9 | -34.1 -29.4  230  51 26   6.9   3.8
 30000 -30.1 -22.2  230  41 21   5.8   3.2 | -30.4 -22.7  230  45 23   5.9   3.3
 29000 -28.4 -19.1  230  38 19   5.8   3.2 | -28.6 -19.5  230  42 22   5.9   3.3
 28000 -26.6 -15.9  230  34 18   7.0   3.9 | -26.3 -15.3  230  38 20   7.4   4.1
 27000 -24.5 -12.1  235  31 16   7.2   4.0 | -24.1 -11.4  230  35 18   7.3   4.0
 26000 -22.3  -8.1  240  28 14   7.2   4.0 | -21.9  -7.4  235  32 17   7.3   4.0
 25000 -20.1  -4.2  245  25 13   7.1   3.9 | -19.8  -3.6  235  29 15   7.3   4.0
 24000 -18.1  -0.6  245  24 12   6.6   3.6 | -17.6   0.3  240  27 14   7.2   4.0
 23000 -16.1   3.0  245  23 12   6.7   3.7 | -15.4   4.3  240  25 13   7.2   4.0
 22000 -14.2   6.4  245  22 11   6.9   3.8 | -13.3   8.1  245  23 12   7.4   4.1
 21000 -11.5  11.3  245  23 12   7.3   4.0 | -11.0  12.2  240  24 12   7.6   4.2
 20000  -9.4  15.1  245  24 12   7.4   4.1 |  -8.8  16.2  240  25 13   7.7   4.2
 19500  -8.3  17.1  245  25 13   7.4   4.1 |  -7.7  18.1  240  25 13   7.5   4.1
 19000  -7.3  18.9  245  26 13   7.4   4.0 |  -6.7  19.9  240  26 13   6.9   3.8
 18500  -6.2  20.8  245  27 14   7.3   4.0 |  -5.7  21.7  240  26 13   6.9   3.8
 18000  -5.1  22.8  245  28 14   8.3   4.5 |  -4.7  23.5  240  26 14   7.1   3.9
 17500  -3.9  25.0  245  28 14   8.3   4.5 |  -3.7  25.3  240  27 14   7.2   4.0
 17000  -2.8  27.0  245  28 14   8.9   4.9 |  -2.7  27.1  240  27 14   7.6   4.2
 16500  -1.4  29.5  240  27 14   9.3   5.1 |  -1.5  29.3  240  27 14   8.5   4.6
 16000  -0.1  31.8  240  25 13   9.3   5.1 |  -0.4  31.3  240  27 14   8.6   4.7
 15500   1.2  34.2  240  24 12   8.6   4.7 |   0.8  33.4  240  26 14   8.7   4.8
 15000   2.5  36.5  240  23 12   8.6   4.7 |   2.1  35.8  235  25 13   8.7   4.8
 14500   3.8  38.8  240  22 11   8.8   4.8 |   3.3  37.9  235  24 12   8.8   4.9
 14000   5.1  41.2  240  21 11   8.8   4.8 |   4.6  40.3  235  23 12   8.9   4.9
 13500   6.4  43.5  240  20 10   8.6   4.7 |   6.6  43.9  235  21 11   8.3   4.6
 13000   7.7  45.9  240  20 10   8.6   4.7 |   7.8  46.0  235  21 11   8.3   4.6
 12500   9.0  48.2  240  19 10   8.7   4.8 |   9.1  48.4  235  20 10   8.9   4.9
 12000  10.3  50.5  240  18  9   8.8   4.8 |  10.5  50.9  235  18  9   9.0   4.9
 11500  11.6  52.9  245  17  9   8.7   4.8 |  11.8  53.2  235  16  8   8.4   4.6
 11000  12.9  55.2  245  17  9   8.3   4.6 |  13.0  55.4  240  15  8   8.6   4.7
 10500  14.2  57.6  245  16  8   4.1   2.3 |  14.0  57.2  245  14  7   4.4   2.4
 10250  14.4  57.9  245  16  8   5.1   2.8 |  14.5  58.1  245  13  7   8.4   4.6
 10000  15.1  59.2  245  15  8  11.4   6.2 |  15.2  59.4  245  13  7  11.1   6.1
  9750  15.9  60.6  245  14  7  10.4   5.7 |  16.0  60.8  250  12  6   9.9   5.4
  9500  16.6  61.9  245  14  7   8.1   4.4 |  16.7  62.1  250  11  6   7.1   3.9
  9250  17.1  62.8  245  13  7   5.3   2.9 |  17.1  62.8  250  11  6   7.3   4.0
  9000  17.5  63.5  245  12  6   7.3   4.0 |  17.8  64.0  250  10  5   9.5   5.2
  8750  18.1  64.6  245  11  6   8.6   4.7 |  18.5  65.3  255   9  5   8.9   4.9
  8500  18.7  65.7  245  10  5   6.4   3.5 |  19.1  66.4  255   8  4   7.9   4.3
  8250  19.0  66.2  240   9  4   4.4   2.4 |  19.7  67.5  255   7  4   7.7   4.2
  8000  19.4  66.9  240   7  4   5.4   3.0 |  20.3  68.5  255   6  3   9.4   5.1
  7750  19.8  67.6  240   6  3   5.9   3.2 |  21.0  69.8  255   6  3  10.3   5.7
  7500  20.2  68.4  235   5  3   5.4   3.0 |  21.7  71.1  260   6  3   9.9   5.4
  7250  20.6  69.1  225   5  3   5.1   2.8 |  22.4  72.3  260   6  3  10.1   5.5
  7000  21.0  69.8  215   5  3   5.2   2.8 |  23.2  73.8  260   6  3   9.8   5.4
  6750  21.3  70.3  205   6  3   4.6   2.5 |  23.9  75.0  260   5  3  10.5   5.8
  6500  21.6  70.9  195   5  3   4.2   2.3 |  24.7  76.5  260   5  3  11.3   6.2
  6250  21.9  71.4  185   4  2   4.1   2.2 |  25.6  78.1  260   5  3  11.2   6.1
  6000  22.1  71.8  175   4  2   4.7   2.6 |  26.4  79.5  260   5  3  11.1   6.1
  5750  22.6  72.7  165   4  2  11.6   6.4 |  27.3  81.1  260   5  3  13.4   7.4
  5500  23.8  74.8  165   3  2  21.2  11.6 |  28.4  83.1  260   5  3  15.8   8.6
  5250     M     M    M   M  M     M     M |  29.5  85.1  260   6  3  14.0   7.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/21/2014 at 1500 MDT          |       07/21/2014 at 1800 MDT
                                           |
K index... +26.3  LI... -0.0               | K index... +22.5  LI... +1.0
CAPE... +54.4  CIN... -57.8                | CAPE... +12.7  CIN... -23.7
                                           |
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 -65.5 -85.9  240  34 18   1.8   1.0 | -65.3 -85.5  240  35 18   1.6   0.9
 45000 -60.6 -77.1  240  55 28   6.3   3.4 | -60.2 -76.4  240  58 30   6.2   3.4
 40000 -50.4 -58.7  235  67 34   7.2   4.0 | -50.5 -58.9  235  68 35   7.3   4.0
 38000 -46.1 -51.0  235  63 33   7.2   4.0 | -46.2 -51.2  235  64 33   7.3   4.0
 36000 -41.8 -43.2  235  60 31   7.0   3.9 | -41.8 -43.2  235  60 31   7.0   3.8
 34000 -37.7 -35.9  235  54 28   6.8   3.7 | -37.9 -36.2  235  52 27   6.5   3.6
 32000 -33.6 -28.5  235  48 25   6.9   3.8 | -34.0 -29.2  235  45 23   6.6   3.6
 30000 -30.1 -22.2  235  44 23   5.8   3.2 | -30.4 -22.7  240  39 20   6.1   3.3
 29000 -28.4 -19.1  235  42 21   5.8   3.2 | -28.1 -18.6  245  36 18   6.1   3.4
 28000 -26.0 -14.8  235  39 20   7.6   4.2 | -26.1 -15.0  250  34 17   7.6   4.2
 27000 -23.8 -10.8  240  36 19   7.5   4.1 | -23.9 -11.0  250  32 17   7.5   4.1
 26000 -21.5  -6.7  240  34 18   7.5   4.1 | -21.6  -6.9  250  31 16   7.5   4.1
 25000 -19.3  -2.7  245  32 16   7.3   4.0 | -19.4  -2.9  255  30 15   7.1   3.9
 24000 -17.1   1.2  245  30 15   7.2   4.0 | -17.3   0.9  255  28 15   7.0   3.8
 23000 -15.0   5.0  245  28 14   7.3   4.0 | -15.3   4.5  255  27 14   7.0   3.8
 22000 -12.8   9.0  245  26 13   7.3   4.0 | -13.1   8.4  260  25 13   8.0   4.4
 21000 -10.7  12.7  245  26 13   7.3   4.0 | -10.7  12.7  255  23 12   8.2   4.5
 20000  -8.5  16.7  245  25 13   7.4   4.1 |  -8.3  17.1  250  21 11   8.2   4.5
 19500  -7.4  18.7  245  25 13   7.3   4.0 |  -7.1  19.2  250  20 10   8.0   4.4
 19000  -6.4  20.5  245  25 13   7.2   4.0 |  -6.0  21.2  245  20 10   7.7   4.2
 18500  -5.4  22.3  240  26 13   7.3   4.0 |  -4.9  23.2  240  20 11   7.7   4.2
 18000  -4.3  24.3  240  26 13   8.1   4.4 |  -3.7  25.3  240  21 11   8.4   4.6
 17500  -3.2  26.2  235  25 13   8.2   4.5 |  -2.5  27.5  240  20 11   8.5   4.7
 17000  -2.0  28.4  235  25 13   8.5   4.6 |  -1.3  29.7  235  20 10   8.6   4.7
 16500  -0.8  30.6  230  24 12   8.7   4.8 |  -0.1  31.8  235  19 10   8.8   4.8
 16000   0.4  32.7  230  22 12   8.8   4.8 |   1.1  34.0  235  18  9   8.8   4.8
 15500   1.7  35.1  230  21 11   9.0   4.9 |   2.4  36.3  235  17  9   9.0   4.9
 15000   3.0  37.4  230  20 10   9.0   4.9 |   3.7  38.7  235  16  8   9.0   4.9
 14500   4.3  39.7  230  19 10   9.0   4.9 |   5.1  41.2  235  15  8   9.1   5.0
 14000   5.6  42.1  230  17  9   9.0   4.9 |   7.1  44.8  235  14  7   9.1   5.0
 13500   7.6  45.7  230  16  8   8.4   4.6 |   8.5  47.3  240  13  7   8.8   4.8
 13000   8.9  48.0  230  15  8   8.5   4.7 |   9.8  49.6  240  13  7   8.9   4.9
 12500  10.1  50.2  230  14  7   8.2   4.5 |  11.1  52.0  245  12  6   8.3   4.6
 12000  11.4  52.5  235  13  7   8.2   4.5 |  12.3  54.1  250  12  6   8.3   4.5
 11500  12.6  54.7  235  12  6   7.9   4.4 |  13.6  56.5  250  11  6   8.2   4.5
 11000  13.7  56.7  240  11  6   8.2   4.5 |  14.8  58.6  255  11  6   8.5   4.7
 10500  14.7  58.5  250  10  5   4.8   2.6 |  15.8  60.4  260  11  6   4.6   2.5
 10250  15.1  59.2  255  10  5   7.9   4.3 |  16.2  61.2  260  11  5   8.2   4.5
 10000  15.8  60.4  260   9  5   9.7   5.3 |  16.9  62.4  265  10  5  10.1   5.6
  9750  16.5  61.7  265   9  5   9.1   5.0 |  17.7  63.9  265  10  5   9.4   5.1
  9500  17.1  62.8  275   9  5   7.2   4.0 |  18.3  64.9  270  10  5   7.1   3.9
  9250  17.7  63.9  275   9  5   8.6   4.7 |  18.8  65.8  275   9  5   7.4   4.1
  9000  18.5  65.3  275   9  5  11.2   6.1 |  19.4  66.9  275   9  4   9.3   5.1
  8750  19.3  66.7  280   9  5  10.6   5.8 |  20.1  68.2  280   8  4   9.0   4.9
  8500  20.0  68.0  280   9  5  10.2   5.6 |  20.7  69.3  285   8  4   9.1   5.0
  8250  20.8  69.4  280   9  5  10.0   5.5 |  21.4  70.5  285   8  4   9.1   5.0
  8000  21.5  70.7  280   9  5  10.4   5.7 |  22.1  71.8  285   8  4   9.5   5.2
  7750  22.3  72.1  280   9  5  10.3   5.6 |  22.8  73.0  285   8  4   9.9   5.4
  7500  23.1  73.6  280   9  5  10.0   5.5 |  23.6  74.5  285   8  4  10.0   5.5
  7250  23.8  74.8  280   9  5   9.8   5.4 |  24.3  75.7  285   8  4  10.0   5.5
  7000  24.5  76.1  280   9  5  10.3   5.7 |  25.1  77.2  285   8  4  10.1   5.5
  6750  25.3  77.5  280   9  5  11.0   6.0 |  25.8  78.4  285   8  4  10.7   5.9
  6500  26.1  79.0  280   9  5  11.0   6.0 |  26.6  79.9  285   7  4  10.9   6.0
  6250  27.0  80.6  280   9  5  11.0   6.0 |  27.4  81.3  285   7  4  11.3   6.2
  6000  27.8  82.0  280   9  5  10.9   6.0 |  28.2  82.8  285   7  4   9.5   5.2
  5750  28.7  83.7  280   9  5  14.0   7.7 |  28.9  84.0  285   7  4  10.1   5.5
  5500  29.9  85.8  280   9  5  16.9   9.2 |  29.8  85.6  285   7  4  12.9   7.1
  5250  31.1  88.0  285   9  5  14.7   8.1 |  30.7  87.3  285   7  4  10.6   5.8
  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 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  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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NOAA National Weather Service
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Silver Spring, MD 20910
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Page last modified: May 16, 2007
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