Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 311257
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0657 MDT Friday, October 31, 2014

This forecast is for Friday, October 31, 2014:

If the trigger temperature of 70.8 F/21.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 186 ft/min (0.9 m/s)
   Maximum height of thermals.................. 9042 ft MSL (4203 ft AGL)

Forecast maximum temperature................... 71.0 F/22.1 C
Time of trigger temperature.................... 1430 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................. 7193 ft MSL (2354 ft AGL)
Thermal soaring outlook for Saturday 11/01..... Fair

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

Remarks...

Sunrise/Sunset.................... 07:40:46 / 18:15:36 MDT
Total possible sunshine........... 10 hr 34 min 50 sec (634 min 50 sec)
Altitude of sun at 12:57:51 MDT... 36.65 degrees

Upper air data from rawinsonde observation taken on 10/31/2014 at 0600 MDT

Freezing level.................. 13545 ft MSL (8706 ft AGL)
Convective condensation level... 19773 ft MSL (14934 ft AGL)
Lifted condensation level....... 16168 ft MSL (11329 ft AGL)
Lifted index.................... +6.3
K index......................... -19.0

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  -66.4 -87.5   265   27   14   9.8   5.4   88.6 191.4    38.2      M    M
 45000  -63.5 -82.3   260   40   20   1.4   0.8   67.4 153.3    28.2      M    M
 40000  -59.4 -74.9   260   38   20   2.7   1.5   51.1 124.0    19.4      M    M
 38000  -56.0 -68.8   255   34   18   8.3   4.6   47.5 117.4    17.5      M    M
 36000  -51.0 -59.8   260   28   15   8.3   4.6   46.1 115.0    17.0      M    M
 34000  -46.4 -51.5   260   24   12   7.4   4.1   44.4 111.9    16.2      M    M
 32000  -41.2 -42.2   235   22   11   7.8   4.3   42.5 108.5    15.3      M    M
 30000  -36.9 -34.4   240   23   12   7.7   4.2   40.6 105.0    14.2      M    M
 29000  -34.5 -30.1   240   17    9   7.7   4.2   39.7 103.4    13.7      M    M
 28000  -32.2 -26.0   240   12    6   7.7   4.2   39.0 102.1    13.3      M    M
 27000  -30.0 -22.0   235   16    8   5.5   3.0   38.0 100.5    12.8      M    M
 26000  -28.6 -19.5   235   21   11   6.7   3.7   36.1  97.0    11.4      M    M
 25000  -26.2 -15.2   235   25   13   8.1   4.5   35.5  95.9    11.0      M    M
 24000  -23.7 -10.7   225   25   13   8.7   4.8   35.0  95.0    10.7      M    M
 23000  -21.1  -6.0   220   26   13   8.4   4.6   34.7  94.4    10.5      M    M
 22000  -18.6  -1.5   220   30   15   8.1   4.5   34.0  93.2    10.1      M    M
 21000  -16.1   3.0   225   34   18   8.5   4.7   33.4  92.2     9.8      M    M
 20000  -14.3   6.3   225   39   20   4.7   2.6   32.1  89.8     8.8      M    M
 19500  -13.2   8.2   225   37   19   9.6   5.3   31.6  89.0     8.5      M    M
 19000  -11.9  10.6   230   35   18   8.6   4.7   31.6  88.8     8.5      M    M
 18500  -10.7  12.7   230   34   18   8.0   4.4   31.2  88.1     8.2      M    M
 18000   -8.9  16.0   225   33   17   8.0   4.4   30.7  87.2     7.8      M    M
 17500   -7.7  18.1   220   32   16   8.0   4.4   30.4  86.7     7.6      M    M
 17000   -6.5  20.3   220   31   16   8.0   4.4   30.1  86.2     7.4      M    M
 16500   -5.3  22.5   215   31   16   8.0   4.4   29.9  85.8     7.2      M    M
 16000   -4.1  24.6   215   30   16   8.0   4.4   29.6  85.3     7.1      M    M
 15500   -2.9  26.8   220   31   16   7.8   4.3   29.3  84.7     6.8      M    M
 15000   -1.7  28.9   220   31   16   6.0   3.3   29.0  84.2     6.6      M    M
 14500   -1.1  30.0   225   32   17   2.2   1.2   28.1  82.6     5.8      M    M
 14000   -0.9  30.4   225   33   17   6.7   3.7   26.9  80.4     4.5      M    M
 13500    0.2  32.4   225   31   16   7.9   4.3   26.6  79.8     4.2      M    M
 13000    1.4  34.5   225   29   15   8.3   4.6   26.3  79.4     3.9      M    M
 12500    2.7  36.9   225   28   14   8.4   4.6   26.1  79.0     3.7      M    M
 12000    3.9  39.0   225   26   13   8.4   4.6   25.9  78.6     3.6      M    M
 11500    5.2  41.4   220   27   14   8.3   4.5   25.7  78.2     3.4      M    M
 11000    6.4  43.5   220   28   15   6.4   3.5   25.4  77.8     3.2      M    M
 10500    7.2  45.0   215   30   15   4.6   2.5   24.6  76.4     2.5      M    M
 10250    7.5  45.5   215   30   16   4.1   2.3   24.2  75.6     2.1      M    M
 10000    7.8  46.0   215   31   16   4.4   2.4   23.8  74.8     1.7      M    M
  9750    8.1  46.6   215   28   15   4.3   2.4   23.3  74.0     1.3      M    M
  9500    8.4  47.1   210   26   13   4.6   2.5   22.9  73.3     0.8      M    M
  9250    8.7  47.7   210   23   12   4.0   2.2   22.5  72.5     0.4      M    M
  9000    9.0  48.2   205   20   10   6.5   3.6   22.1  71.8    -0.0    285  1.4
  8750    9.6  49.3   200   18    9   9.1   5.0   22.0  71.6    -0.1    258  1.3
  8500   10.3  50.5   190   17    9   8.4   4.6   21.9  71.4    -0.2    232  1.2
  8250   10.9  51.6   180   16    8   8.8   4.8   21.8  71.3    -0.3    206  1.0
  8000   11.5  52.7   165   15    8   7.8   4.3   21.7  71.1    -0.4    179  0.9
  7750   12.2  54.0   160   16    8  11.2   6.2   21.6  71.0    -0.5    153  0.8
  7500   12.8  55.0   155   17    9  -1.5  -0.8   21.5  70.8    -0.6    127  0.6
  7250   11.9  53.4   155   18    9 -17.3  -9.5   19.8  67.7    -2.2    146  0.7
  7000   10.9  51.6   150   19   10  -8.0  -4.4   18.0  64.5    -4.0    169  0.9
  6750   10.8  51.4   150   17    9   3.6   2.0   17.2  62.9    -4.9    165  0.8
  6500   11.2  52.2   145   14    7   6.3   3.5   16.9  62.3    -5.2    145  0.7
  6250   11.6  52.9   140   11    6   6.0   3.3   16.6  61.8    -5.5    126  0.6
  6000   12.0  53.6   135    9    4   4.7   2.6   16.3  61.3    -5.8    106  0.5
  5750   12.2  54.0   130    8    4  -0.9  -0.5   15.7  60.2    -6.5     94  0.5
  5500   12.1  53.8   130    7    4   3.4   1.9   14.9  58.8    -7.3     89  0.5
  5250   12.0  53.6   130    7    3 -16.8  -9.2   14.1  57.4    -8.1     84  0.4
  5000    8.9  48.0   130    6    3 -60.9 -33.4   10.3  50.6   -11.9    169  0.9

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

           10/31/2014 at 0900 MDT          |       10/31/2014 at 1200 MDT
                                           |
K index... +9.9  LI... +3.6                | K index... +13.3  LI... +2.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.7
                                           |
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 -67.0 -88.6  270  34 17   1.8   1.0 | -66.9 -88.4  260  31 16   1.9   1.0
 45000 -63.8 -82.8  265  38 19   3.7   2.0 | -63.7 -82.7  265  35 18   3.6   2.0
 40000 -58.3 -72.9  260  31 16   4.0   2.2 | -58.0 -72.4  255  30 15   4.2   2.3
 38000 -54.7 -66.5  250  29 15   6.2   3.4 | -54.4 -65.9  245  30 16   6.1   3.3
 36000 -51.0 -59.8  235  28 14   6.2   3.4 | -50.8 -59.4  235  32 17   6.1   3.3
 34000 -46.6 -51.9  235  26 13   8.2   4.5 | -46.7 -52.1  230  30 16   7.4   4.1
 32000 -41.1 -42.0  240  23 12   8.2   4.5 | -42.3 -44.1  230  26 13   7.4   4.1
 30000 -36.6 -33.9  240  19 10   7.0   3.8 | -37.4 -35.3  235  21 11   8.6   4.7
 29000 -34.5 -30.1  240  17  9   7.0   3.8 | -34.9 -30.8  240  19 10   8.6   4.7
 28000 -32.4 -26.3  235  16  8   7.0   3.8 | -31.6 -24.9  250  17  9   8.8   4.8
 27000 -30.3 -22.5  230  16  8   7.4   4.0 | -29.4 -20.9  245  16  8   7.2   4.0
 26000 -28.1 -18.6  225  16  8   7.4   4.0 | -27.2 -17.0  230  16  8   7.2   4.0
 25000 -25.8 -14.4  220  17  9   7.4   4.1 | -25.0 -13.0  220  18  9   7.2   4.0
 24000 -23.5 -10.3  215  19 10   7.9   4.4 | -22.9  -9.2  215  20 10   6.6   3.6
 23000 -21.2  -6.2  220  22 11   8.0   4.4 | -21.0  -5.8  220  22 11   6.6   3.6
 22000 -18.8  -1.8  220  25 13   8.0   4.4 | -19.0  -2.2  220  24 13   6.6   3.6
 21000 -16.7   1.9  220  27 14   6.2   3.4 | -17.0   1.4  220  26 14   6.5   3.6
 20000 -14.8   5.4  225  28 15   6.2   3.4 | -15.1   4.8  225  28 14   6.5   3.6
 19500 -13.9   7.0  225  29 15   6.2   3.4 | -14.1   6.6  225  28 15   6.5   3.6
 19000 -13.0   8.6  225  30 15   6.5   3.6 | -13.1   8.4  225  29 15   6.9   3.8
 18500 -12.0  10.4  230  29 15   7.1   3.9 | -12.0  10.4  230  28 15   7.5   4.1
 18000 -10.4  13.3  230  29 15   7.2   4.0 | -10.9  12.4  230  28 14   7.6   4.2
 17500  -9.3  15.3  230  29 15   7.5   4.1 |  -9.9  14.2  230  27 14   6.2   3.4
 17000  -8.2  17.2  230  29 15   7.6   4.2 |  -9.0  15.8  230  28 14   6.4   3.5
 16500  -7.2  19.0  230  29 15   7.0   3.9 |  -8.0  17.6  230  28 14   6.4   3.5
 16000  -6.1  21.0  225  29 15   7.2   3.9 |  -7.1  19.2  230  29 15   6.5   3.6
 15500  -5.1  22.8  225  29 15   7.5   4.1 |  -6.2  20.8  230  29 15   6.8   3.7
 15000  -4.0  24.8  225  28 15   7.7   4.2 |  -5.2  22.6  230  30 15   7.4   4.1
 14500  -2.9  26.8  225  28 14   7.8   4.3 |  -4.1  24.6  225  30 16   7.4   4.0
 14000  -1.7  28.9  225  27 14   8.0   4.4 |  -3.0  26.6  225  31 16   8.6   4.7
 13500  -0.5  31.1  225  25 13   8.2   4.5 |  -1.1  30.0  225  30 16   8.4   4.6
 13000   0.8  33.4  230  25 13   8.9   4.9 |   0.1  32.2  230  30 15   8.3   4.5
 12500   2.1  35.8  230  24 12   8.8   4.8 |   1.3  34.3  230  29 15   8.2   4.5
 12000   3.3  37.9  230  25 13   8.2   4.5 |   2.5  36.5  230  28 14   7.9   4.4
 11500   4.6  40.3  225  25 13   8.3   4.5 |   3.6  38.5  235  27 14   8.0   4.4
 11000   5.8  42.4  225  26 13   7.6   4.2 |   4.8  40.6  235  26 14   7.9   4.3
 10500   6.9  44.4  220  27 14   7.4   4.1 |   6.0  42.8  235  25 13   5.5   3.0
 10250   7.4  45.3  220  27 14   4.2   2.3 |   6.3  43.3  235  25 13   4.7   2.6
 10000   7.7  45.9  215  28 14   5.6   3.1 |   6.8  44.2  235  25 13   8.4   4.6
  9750   8.3  46.9  215  29 15   8.8   4.8 |   7.5  45.5  235  24 12   9.0   4.9
  9500   8.9  48.0  210  29 15   7.6   4.2 |   8.1  46.6  235  24 12   7.0   3.9
  9250   9.4  48.9  210  30 16   5.2   2.9 |   8.5  47.3  230  24 12   3.8   2.1
  9000   9.7  49.5  205  31 16   4.1   2.3 |   8.8  47.8  225  23 12   3.6   2.0
  8750  10.0  50.0  205  31 16   5.3   2.9 |   9.1  48.4  225  22 12   4.4   2.4
  8500  10.4  50.7  205  31 16   4.4   2.4 |   9.4  48.9  220  22 11   3.1   1.7
  8250  10.7  51.3  200  30 15   3.1   1.7 |   9.5  49.1  215  20 10   1.5   0.8
  8000  10.8  51.4  200  29 15   2.4   1.3 |   9.7  49.5  205  17  9   2.3   1.3
  7750  11.0  51.8  195  27 14   2.2   1.2 |   9.9  49.8  200  15  8   3.3   1.8
  7500  11.1  52.0  190  25 13   0.7   0.4 |  10.2  50.4  195  13  6   6.2   3.4
  7250  11.1  52.0  185  23 12  -0.5  -0.3 |  10.8  51.4  190  11  6   8.1   4.4
  7000  11.1  52.0  180  22 11  -0.1  -0.1 |  11.4  52.5  190  10  5   7.6   4.2
  6750  11.1  52.0  175  20 10  -0.4  -0.2 |  12.0  53.6  190  10  5   9.2   5.1
  6500  11.0  51.8  170  18  9  -3.7  -2.1 |  12.7  54.9  190   9  5  10.6   5.8
  6250  10.5  50.9  165  15  8  -6.2  -3.4 |  13.5  56.3  190   9  4  10.9   6.0
  6000  10.1  50.2  160  13  7  -4.7  -2.6 |  14.3  57.7  190   8  4   9.7   5.3
  5750   9.7  49.5  150  11  6  -8.0  -4.4 |  15.0  59.0  190   7  4   9.5   5.2
  5500   8.7  47.7  120   7  4 -19.7 -10.8 |  15.8  60.4  190   7  4  11.0   6.0
  5250     M     M    M   M  M     M     M |  16.6  61.9  190   7  4   9.8   5.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           10/31/2014 at 1500 MDT          |       10/31/2014 at 1800 MDT
                                           |
K index... +14.7  LI... +2.4               | K index... +16.9  LI... +2.5
CAPE... 0.0  CIN... -0.6                   | CAPE... 0.0  CIN... -0.4
                                           |
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 -66.6 -87.9  260  31 16   2.1   1.2 | -67.4 -89.3  245  33 17   2.2   1.2
 45000 -63.2 -81.8  260  34 18   3.4   1.9 | -63.9 -83.0  255  38 19   3.0   1.7
 40000 -57.7 -71.9  275  33 17   4.2   2.3 | -59.4 -74.9  265  39 20   2.5   1.4
 38000 -54.0 -65.2  270  32 17   6.4   3.5 | -55.3 -67.5  270  38 19   7.3   4.0
 36000 -50.1 -58.2  270  31 16   6.4   3.5 | -51.0 -59.8  275  36 19   7.3   4.0
 34000 -46.2 -51.2  260  28 15   6.5   3.5 | -46.3 -51.3  280  35 18   8.3   4.6
 32000 -42.4 -44.3  235  28 14   6.5   3.5 | -40.6 -41.1  285  32 17   8.3   4.6
 30000 -37.8 -36.0  225  26 13   8.8   4.8 | -35.7 -32.3  285  29 15   8.0   4.4
 29000 -35.1 -31.2  225  23 12   8.8   4.9 | -33.3 -27.9  280  28 14   8.0   4.4
 28000 -32.5 -26.5  225  21 11   8.8   4.8 | -30.9 -23.6  280  26 13   8.1   4.4
 27000 -29.6 -21.3  230  22 11   6.7   3.7 | -29.2 -20.6  270  26 13   4.3   2.3
 26000 -27.6 -17.7  235  25 13   6.7   3.7 | -28.0 -18.4  265  27 14   4.2   2.3
 25000 -25.6 -14.1  240  29 15   6.8   3.7 | -26.7 -16.1  255  28 15   4.4   2.4
 24000 -23.5 -10.3  245  29 15   7.3   4.0 | -25.0 -13.0  250  30 15   8.4   4.6
 23000 -21.3  -6.3  250  28 14   7.4   4.0 | -22.6  -8.7  250  30 15   8.3   4.5
 22000 -19.2  -2.6  260  27 14   7.4   4.1 | -20.1  -4.2  250  30 16   8.3   4.5
 21000 -17.1   1.2  260  27 14   6.6   3.6 | -17.8  -0.0  250  30 15   7.8   4.3
 20000 -15.2   4.6  255  27 14   6.6   3.6 | -15.4   4.3  250  29 15   7.8   4.3
 19500 -14.2   6.4  250  27 14   6.6   3.6 | -14.3   6.3  245  28 14   7.8   4.3
 19000 -13.2   8.2  245  28 14   6.6   3.6 | -13.1   8.4  245  27 14   7.4   4.1
 18500 -12.2  10.0  245  28 14   6.6   3.6 | -12.2  10.0  245  28 14   5.5   3.0
 18000 -11.2  11.8  240  27 14   6.6   3.6 | -11.3  11.7  240  29 15   5.6   3.0
 17500 -10.2  13.6  235  28 14   7.3   4.0 | -10.3  13.5  240  30 15   7.4   4.0
 17000  -9.1  15.6  235  28 14   7.3   4.0 |  -9.1  15.6  240  30 15   7.7   4.2
 16500  -8.0  17.6  230  28 14   7.0   3.8 |  -7.9  17.8  240  30 15   7.5   4.1
 16000  -7.0  19.4  230  28 14   6.8   3.7 |  -6.9  19.6  240  30 15   6.9   3.8
 15500  -6.1  21.0  230  28 15   6.8   3.7 |  -5.5  22.1  235  30 16   6.8   3.8
 15000  -5.1  22.8  230  28 15   6.4   3.5 |  -4.5  23.9  235  30 15   6.9   3.8
 14500  -4.2  24.4  230  28 15   6.3   3.5 |  -3.6  25.5  235  29 15   7.2   3.9
 14000  -3.2  26.2  230  28 14   8.4   4.6 |  -2.5  27.5  230  28 14   7.6   4.2
 13500  -1.4  29.5  230  27 14   8.2   4.5 |  -1.4  29.5  230  27 14   7.7   4.2
 13000  -0.2  31.6  225  27 14   8.2   4.5 |  -0.2  31.6  225  26 13   8.1   4.5
 12500   1.1  34.0  225  27 14   8.2   4.5 |   1.0  33.8  225  25 13   8.1   4.4
 12000   2.3  36.1  225  27 14   7.9   4.3 |   2.3  36.1  220  25 13   8.7   4.8
 11500   3.4  38.1  225  27 14   7.9   4.3 |   3.7  38.7  220  25 13   8.7   4.8
 11000   4.6  40.3  220  26 14   7.4   4.1 |   4.9  40.8  215  25 13   7.8   4.3
 10500   5.7  42.3  215  25 13   4.5   2.5 |   6.1  43.0  210  25 13   5.2   2.8
 10250   6.0  42.8  215  24 12   5.2   2.9 |   6.4  43.5  210  25 13   6.3   3.5
 10000   6.6  43.9  210  23 12   9.6   5.3 |   7.1  44.8  210  24 12  10.8   5.9
  9750   7.2  45.0  210  22 11   8.7   4.8 |   7.8  46.0  205  23 12   9.7   5.3
  9500   7.9  46.2  205  20 10   8.2   4.5 |   8.5  47.3  205  23 12   9.6   5.3
  9250   8.4  47.1  205  19 10   7.0   3.9 |   9.2  48.6  205  22 11   7.9   4.3
  9000   9.0  48.2  205  18  9   8.2   4.5 |   9.8  49.6  200  22 11   8.5   4.7
  8750   9.6  49.3  205  16  8   9.2   5.0 |  10.5  50.9  200  21 11   9.9   5.4
  8500  10.3  50.5  205  15  8   8.4   4.6 |  11.2  52.2  200  21 11   9.3   5.1
  8250  10.9  51.6  205  13  7   7.6   4.2 |  11.9  53.4  200  20 10   9.1   5.0
  8000  11.4  52.5  205  12  6   8.0   4.4 |  12.5  54.5  195  19 10   8.7   4.8
  7750  12.0  53.6  205  11  6   8.3   4.5 |  13.2  55.8  195  19 10   8.6   4.7
  7500  12.7  54.9  210  10  5   9.1   5.0 |  13.8  56.8  195  18  9   8.6   4.7
  7250  13.4  56.1  210  10  5  10.0   5.5 |  14.5  58.1  195  17  9   8.5   4.7
  7000  14.1  57.4  210   9  5   9.4   5.2 |  15.1  59.2  195  15  8   8.3   4.6
  6750  14.8  58.6  215   9  5   9.5   5.2 |  15.7  60.3  195  14  7   7.8   4.3
  6500  15.6  60.1  215   9  4  10.3   5.6 |  16.3  61.3  195  13  7   7.8   4.3
  6250  16.3  61.3  215   8  4  11.0   6.0 |  16.9  62.4  195  12  6   7.3   4.0
  6000  17.1  62.8  215   8  4   9.3   5.1 |  17.4  63.3  195  10  5   9.1   5.0
  5750  17.8  64.0  220   7  4   8.8   4.8 |  18.0  64.4  190   8  4   4.3   2.4
  5500  18.5  65.3  220   7  4  10.3   5.6 |  18.0  64.4  190   6  3  -3.7  -2.0
  5250  19.2  66.6  220   7  4   9.0   5.0 |  17.7  63.9  190   5  3  -0.7  -0.4
  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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