Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 211238
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0538 MST Saturday, January 21, 2017

This forecast is for Saturday, January 21, 2017:

If the trigger temperature of 43.0 F/6.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 4964 ft MSL (125 ft AGL)

Forecast maximum temperature................... 36.0 F/2.7 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Sunday 01/22....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:28:32 / 17:21:41 MST
Total possible sunshine........... 9 hr 53 min 8 sec (593 min 8 sec)
Altitude of sun at 12:25:30 MST... 31.22 degrees

Upper air data from rawinsonde observation taken on 01/21/2017 at 0500 MST

Freezing level.................. 5992 ft MSL (1153 ft AGL)
Convective condensation level... 11562 ft MSL (6723 ft AGL)
Lifted condensation level....... 8617 ft MSL (3777 ft AGL)
Lifted index.................... +7.5
K index......................... +18.9

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  -51.3 -60.3   245   27   14   7.1   3.9  117.0 242.6    65.3      M    M
 45000  -47.6 -53.7   280   33   17  -0.4  -0.2   97.3 207.2    57.9      M    M
 40000  -46.4 -51.5   270   28   14   6.3   3.5   76.0 168.8    47.9      M    M
 38000  -44.2 -47.6   270   29   15   5.1   2.8   70.4 158.6    45.4      M    M
 36000  -43.8 -46.8   255   36   18  -1.8  -1.0   62.4 144.2    41.1      M    M
 34000  -45.9 -50.6   245   33   17  -0.5  -0.3   50.9 123.7    34.2      M    M
 32000  -47.1 -52.8   240   21   11   4.9   2.7   41.1 105.9    27.9      M    M
 30000  -49.6 -57.3   225   53   27  -4.5  -2.4   28.6  83.5    19.6      M    M
 29000  -52.1 -61.8   200   64   33   4.3   2.4   21.3  70.4    14.3      M    M
 28000  -49.7 -57.5   200   58   30   8.6   4.7   20.5  68.9    13.9      M    M
 27000  -47.1 -52.8   200   53   27   8.6   4.7   20.0  68.1    13.7      M    M
 26000  -44.6 -48.3   205   47   24   8.6   4.7   19.7  67.4    13.6      M    M
 25000  -42.0 -43.6   205   42   22   8.6   4.7   19.4  67.0    13.6      M    M
 24000  -39.4 -38.9   205   40   20   8.6   4.7   18.9  66.0    13.3      M    M
 23000  -36.8 -34.2   210   37   19   8.8   4.8   18.5  65.3    13.2      M    M
 22000  -34.2 -29.6   215   36   18   8.6   4.7   18.0  64.4    12.9      M    M
 21000  -31.7 -25.1   220   34   18   8.6   4.7   17.6  63.7    12.7      M    M
 20000  -29.1 -20.4   225   33   17   8.8   4.8   17.3  63.1    12.6      M    M
 19500  -27.9 -18.2   225   29   15   7.3   4.0   17.0  62.6    12.4      M    M
 19000  -26.8 -16.2   220   25   13   7.3   4.0   16.5  61.7    12.1      M    M
 18500  -25.7 -14.3   215   21   11   7.3   4.0   16.1  61.0    11.8      M    M
 18000  -24.6 -12.3   210   17    9   7.3   4.0   15.7  60.2    11.5      M    M
 17500  -23.5 -10.3   205   14    7   7.2   4.0   15.3  59.5    11.2      M    M
 17000  -22.5  -8.5   210   12    6   7.2   3.9   14.9  58.8    10.9      M    M
 16500  -20.9  -5.6   215   11    6   7.2   4.0   14.3  57.7    10.4      M    M
 16000  -19.8  -3.6   220   11    6   7.2   4.0   13.9  57.0    10.1      M    M
 15500  -18.8  -1.8   230   13    7   7.2   4.0   13.5  56.2     9.8      M    M
 15000  -17.7   0.1   235   15    8   7.2   4.0   13.1  55.5     9.5      M    M
 14500  -16.6   2.1   225   15    8   7.2   4.0   12.6  54.7     9.1      M    M
 14000  -15.6   3.9   215   16    8   7.2   4.0   12.2  54.0     8.8      M    M
 13500  -14.5   5.9   220   19   10   7.3   4.0   11.8  53.2     8.4      M    M
 13000  -13.4   7.9   225   21   11   7.3   4.0   11.4  52.5     8.1      M    M
 12500  -12.4   9.7   220   23   12   7.3   4.0   10.9  51.7     7.7      M    M
 12000  -11.3  11.7   215   25   13   7.3   4.0   10.5  50.9     7.3      M    M
 11500  -10.2  13.6   205   27   14   6.8   3.7   10.1  50.2     6.9      M    M
 11000   -9.4  15.1   195   30   15   5.8   3.2    9.5  49.1     6.4      M    M
 10500   -8.5  16.7   195   26   14   5.8   3.2    8.8  47.9     5.8      M    M
 10250   -8.1  17.4   195   25   13   5.8   3.2    8.5  47.3     5.5      M    M
 10000   -7.7  18.1   195   23   12   5.8   3.2    8.2  46.7     5.2      M    M
  9750   -7.2  19.0   200   21   11   5.8   3.2    7.9  46.2     4.9      M    M
  9500   -6.8  19.8   200   19   10   5.8   3.2    7.6  45.7     4.6      M    M
  9250   -6.4  20.5   195   18    9   5.1   2.8    7.3  45.1     4.3      M    M
  9000   -6.1  21.0   185   17    9   4.6   2.5    6.9  44.4     4.0      M    M
  8750   -5.7  21.7   175   18    9   4.7   2.6    6.5  43.7     3.6      M    M
  8500   -5.4  22.3   165   20   10   4.7   2.6    6.1  42.9     3.2      M    M
  8250   -5.0  23.0   155   22   11   4.7   2.6    5.7  42.2     2.9      M    M
  8000   -4.7  23.5   150   25   13   4.7   2.6    5.3  41.5     2.5      M    M
  7750   -4.3  24.3   150   23   12   4.6   2.5    4.9  40.8     2.1      M    M
  7500   -4.0  24.8   150   21   11   4.8   2.6    4.5  40.1     1.8      M    M
  7250   -3.5  25.7   155   19   10   7.6   4.2    4.2  39.6     1.5      M    M
  7000   -2.8  27.0   155   16    8   9.4   5.2    4.2  39.5     1.4      M    M
  6750   -2.2  28.0   155   15    8   9.0   4.9    4.1  39.4     1.4      M    M
  6500   -1.5  29.3   155   14    7   9.0   4.9    4.1  39.3     1.3      M    M
  6250   -0.8  30.6   155   13    7   9.3   5.1    4.0  39.2     1.3      M    M
  6000   -0.2  31.6   155   12    6   8.1   4.4    4.0  39.1     1.2      M    M
  5750    0.4  32.7   150   11    5   6.3   3.5    3.7  38.7     1.0      M    M
  5500    0.8  33.4   135    9    5   6.3   3.4    3.5  38.3     0.7      M    M
  5250    1.3  34.3   120    8    4   6.3   3.5    3.2  37.8     0.5      M    M
  5000    1.7  35.1   100    7    4   6.1   3.3    3.0  37.3     0.2      M    M

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

           01/21/2017 at 0800 MST          |       01/21/2017 at 1100 MST
                                           |
K index... +21.8  LI... +1.1               | K index... +22.5  LI... +1.2
CAPE... 0.0  CIN... -0.2                   | CAPE... 0.0  CIN... -2.6
                                           |
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 -52.2 -62.0  280  37 19   2.7   1.5 | -51.8 -61.2  280  43 22   2.8   1.5
 45000 -47.9 -54.2  285  44 23   2.7   1.5 | -47.7 -53.9  285  52 27   2.8   1.5
 40000 -44.1 -47.4  275  42 22   2.5   1.4 | -43.7 -46.7  285  50 26   2.7   1.5
 38000 -42.6 -44.7  275  41 21   0.9   0.5 | -42.1 -43.8  285  49 25   0.9   0.5
 36000 -42.9 -45.2  270  36 18  -0.4  -0.2 | -42.2 -44.0  280  41 21  -0.1  -0.1
 34000 -43.1 -45.6  265  31 16  -0.4  -0.2 | -42.3 -44.1  270  36 18  -0.1  -0.1
 32000 -44.4 -47.9  255  28 14  -2.9  -1.6 | -43.4 -46.1  265  29 15  -2.8  -1.5
 30000 -46.1 -51.0  240  27 14  -3.0  -1.6 | -45.1 -49.2  250  22 11  -2.8  -1.5
 29000 -46.8 -52.2  230  27 14   0.2   0.1 | -45.8 -50.4  240  20 10  -0.2  -0.1
 28000 -46.7 -52.1  225  27 14   0.3   0.2 | -45.8 -50.4  225  18  9  -0.1  -0.1
 27000 -46.6 -51.9  215  27 14   0.3   0.2 | -45.8 -50.4  210  18  9  -0.1  -0.1
 26000 -46.5 -51.7  205  28 15   0.0   0.0 | -45.9 -50.6  190  19 10  -0.5  -0.3
 25000 -44.0 -47.2  205  29 15  10.5   5.8 | -44.0 -47.2  195  20 10   8.0   4.4
 24000 -40.9 -41.6  205  30 15  10.5   5.7 | -41.6 -42.9  200  21 11   7.9   4.3
 23000 -37.8 -36.0  205  31 16  10.6   5.8 | -39.3 -38.7  205  22 11   7.9   4.3
 22000 -35.1 -31.2  205  30 15   8.8   4.8 | -36.6 -33.9  215  21 11   9.3   5.1
 21000 -32.4 -26.3  205  28 14   8.8   4.8 | -33.8 -28.8  225  20 10   9.3   5.1
 20000 -29.8 -21.6  205  26 14   8.3   4.6 | -30.4 -22.7  235  19 10   8.9   4.9
 19500 -28.6 -19.5  200  25 13   7.9   4.3 | -29.1 -20.4  235  19 10   9.0   4.9
 19000 -26.9 -16.4  200  22 11   7.9   4.3 | -27.7 -17.9  240  18 10   9.0   4.9
 18500 -25.7 -14.3  195  20 10   7.9   4.3 | -26.4 -15.5  240  18  9   9.0   4.9
 18000 -24.5 -12.1  190  19 10   7.9   4.3 | -25.1 -13.2  240  18  9   9.1   5.0
 17500 -23.4 -10.1  185  17  9   7.7   4.2 | -23.8 -10.8  240  16  8   7.8   4.3
 17000 -22.3  -8.1  185  15  8   7.7   4.2 | -22.7  -8.9  235  15  8   8.0   4.4
 16500 -21.1  -6.0  185  13  7   7.1   3.9 | -21.5  -6.7  230  13  7   7.0   3.8
 16000 -20.1  -4.2  190  11  6   6.8   3.7 | -20.5  -4.9  230  12  6   6.7   3.7
 15500 -19.1  -2.4  195   9  4   6.7   3.7 | -19.6  -3.3  230  11  6   6.8   3.7
 15000 -18.2  -0.8  210   8  4   6.6   3.6 | -18.5  -1.3  235  11  6   7.0   3.8
 14500 -17.2   1.0  225   7  4   6.6   3.6 | -17.5   0.5  245  11  6   7.0   3.9
 14000 -16.1   3.0  240   7  4   7.4   4.1 | -16.4   2.5  250  11  6   7.6   4.2
 13500 -15.1   4.8  255   8  4   7.4   4.0 | -15.3   4.5  255  11  6   7.6   4.2
 13000 -14.0   6.8  265  10  5   7.0   3.9 | -14.2   6.4  260  10  5   7.3   4.0
 12500 -13.0   8.6  270  12  6   7.1   3.9 | -13.1   8.4  260  10  5   7.4   4.1
 12000 -12.0  10.4  270  13  7   6.5   3.6 | -12.1  10.2  265   9  5   6.9   3.8
 11500 -11.0  12.2  270  15  8   6.5   3.5 | -11.1  12.0  270  10  5   7.0   3.8
 11000 -10.0  14.0  265  17  9   7.2   4.0 | -10.1  13.8  270  10  5   6.5   3.6
 10500  -9.0  15.8  265  18  9   6.9   3.8 |  -9.1  15.6  270  12  6   6.2   3.4
 10250  -8.4  16.9  265  18  9   8.9   4.9 |  -8.6  16.5  270  12  6   8.1   4.4
 10000  -7.8  18.0  260  18  9   8.2   4.5 |  -8.0  17.6  270  13  7   7.1   3.9
  9750  -7.3  18.9  260  17  9   5.9   3.2 |  -7.6  18.3  265  14  7   4.5   2.5
  9500  -6.8  19.8  255  17  9   6.5   3.5 |  -7.3  18.9  265  15  8   5.2   2.9
  9250  -6.4  20.5  255  17  9   6.5   3.6 |  -6.9  19.6  265  15  8   5.7   3.1
  9000  -5.9  21.4  245  15  8   6.5   3.6 |  -6.4  20.5  265  16  8   6.3   3.4
  8750  -5.4  22.3  240  14  7   6.2   3.4 |  -6.0  21.2  265  16  8   6.5   3.5
  8500  -5.0  23.0  230  14  7   5.9   3.2 |  -5.5  22.1  265  16  8   6.3   3.5
  8250  -4.6  23.7  220  13  7   4.5   2.5 |  -5.1  22.8  265  16  8   5.8   3.2
  8000  -4.3  24.3  210  13  6   3.7   2.0 |  -4.7  23.5  265  15  8   5.6   3.1
  7750  -4.0  24.8  200  12  6   3.9   2.1 |  -4.2  24.4  265  15  8   6.7   3.7
  7500  -3.8  25.2  190  12  6   3.5   1.9 |  -3.7  25.3  265  14  7   6.2   3.4
  7250  -3.5  25.7  180  12  6   3.2   1.7 |  -3.4  25.9  265  11  6   4.9   2.7
  7000  -3.3  26.1  170  12  6   2.8   1.6 |  -3.0  26.6  260   9  5   5.2   2.9
  6750  -3.1  26.4  165  12  6   4.3   2.3 |  -2.6  27.3  250   7  4   5.4   3.0
  6500  -2.7  27.1  160  11  6   5.7   3.1 |  -2.2  28.0  240   6  3   6.2   3.4
  6250  -2.3  27.9  155   9  5   5.4   3.0 |  -1.7  28.9  230   5  2   6.7   3.7
  6000  -1.9  28.6  150   7  4   5.4   2.9 |  -1.3  29.7  215   4  2   5.7   3.1
  5750  -1.5  29.3  140   5  3   5.8   3.2 |  -0.8  30.6  200   4  2   9.3   5.1
  5500  -1.0  30.2  135   4  2   7.2   4.0 |   0.2  32.4  205   3  2  17.7   9.7
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/21/2017 at 1400 MST          |       01/21/2017 at 1700 MST
                                           |
K index... +20.5  LI... +0.3               | K index... +19.3  LI... +0.9
CAPE... +1.7  CIN... -0.9                  | CAPE... +12.7  CIN... -2.2
                                           |
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 -52.2 -62.0  280  50 26   3.3   1.8 | -53.4 -64.1  285  53 27   3.5   1.9
 45000 -47.3 -53.1  285  60 31   3.2   1.8 | -48.1 -54.6  285  64 33   3.5   1.9
 40000 -43.2 -45.8  290  61 31   2.7   1.5 | -43.4 -46.1  295  71 37   3.0   1.6
 38000 -41.6 -42.9  290  59 31  -0.1  -0.0 | -41.8 -43.2  300  73 37   0.6   0.3
 36000 -41.5 -42.7  290  53 27   0.1   0.1 | -41.5 -42.7  295  67 35   0.6   0.3
 34000 -41.4 -42.5  285  47 24   0.1   0.1 | -41.1 -42.0  295  62 32   0.6   0.3
 32000 -42.6 -44.7  280  37 19  -3.1  -1.7 | -41.9 -43.4  295  52 27  -2.2  -1.2
 30000 -44.5 -48.1  270  26 13  -3.1  -1.7 | -43.2 -45.8  290  41 21  -2.2  -1.2
 29000 -45.3 -49.5  260  21 11  -0.8  -0.4 | -43.8 -46.8  285  34 18  -1.7  -0.9
 28000 -45.5 -49.9  240  17  9  -0.9  -0.5 | -44.3 -47.7  275  25 13  -1.7  -0.9
 27000 -45.8 -50.4  215  16  8  -0.9  -0.5 | -44.8 -48.6  255  18  9  -1.7  -0.9
 26000 -46.1 -51.0  195  18  9  -0.9  -0.5 | -45.3 -49.5  220  16  8  -0.8  -0.4
 25000 -44.2 -47.6  195  16  8   8.0   4.4 | -43.7 -46.7  215  14  7   6.8   3.7
 24000 -41.8 -43.2  210  13  7   8.0   4.4 | -41.7 -43.1  220  12  6   6.7   3.7
 23000 -39.4 -38.9  225  12  6   8.0   4.4 | -39.1 -38.4  225   9  5   8.3   4.5
 22000 -36.9 -34.4  240  10  5   8.8   4.8 | -36.5 -33.7  235   8  4   8.7   4.8
 21000 -33.6 -28.5  265   9  5   8.8   4.8 | -33.8 -28.8  245   8  4   8.8   4.8
 20000 -31.0 -23.8  280  10  5   8.4   4.6 | -31.2 -24.2  260   8  4   8.7   4.8
 19500 -29.7 -21.5  280  11  6   8.4   4.6 | -29.9 -21.8  265   8  4   8.7   4.8
 19000 -28.5 -19.3  285  12  6   8.4   4.6 | -28.6 -19.5  270   8  4   8.7   4.8
 18500 -27.2 -17.0  285  13  6   8.5   4.6 | -27.3 -17.1  275   9  5   8.7   4.8
 18000 -25.9 -14.6  285  14  7   8.5   4.6 | -26.0 -14.8  280   9  5   8.5   4.7
 17500 -24.7 -12.5  285  14  7   8.8   4.9 | -24.8 -12.6  285  10  5   8.0   4.4
 17000 -23.3  -9.9  285  14  7   8.9   4.9 | -23.6 -10.5  285  11  6   8.1   4.4
 16500 -22.1  -7.8  285  14  7   8.0   4.4 | -22.5  -8.5  290  12  6   7.1   3.9
 16000 -20.9  -5.6  290  14  7   7.9   4.3 | -21.4  -6.5  290  14  7   7.1   3.9
 15500 -19.7  -3.5  290  14  7   7.7   4.2 | -20.4  -4.7  295  15  8   7.1   3.9
 15000 -18.6  -1.5  290  15  8   7.6   4.1 | -19.3  -2.7  295  17  9   7.1   3.9
 14500 -17.5   0.5  285  16  8   7.5   4.1 | -18.3  -0.9  300  19 10   7.3   4.0
 14000 -16.4   2.5  285  17  9   7.1   3.9 | -17.2   1.0  300  20 10   7.5   4.1
 13500 -15.4   4.3  280  18  9   7.1   3.9 | -16.1   3.0  305  21 11   7.5   4.1
 13000 -14.3   6.3  280  18  9   7.4   4.0 | -15.0   5.0  305  21 11   7.3   4.0
 12500 -13.2   8.2  275  18  9   7.4   4.0 | -13.9   7.0  305  22 11   7.3   4.0
 12000 -12.2  10.0  275  18  9   6.8   3.7 | -12.8   9.0  310  23 12   7.3   4.0
 11500 -11.2  11.8  275  18  9   6.8   3.8 | -11.8  10.8  310  23 12   7.2   4.0
 11000 -10.2  13.6  275  18  9   6.8   3.7 | -10.7  12.7  310  24 12   7.0   3.8
 10500  -9.2  15.4  270  18  9   6.8   3.7 |  -9.7  14.5  310  25 13   7.0   3.8
 10250  -8.7  16.3  270  18  9   6.9   3.8 |  -9.2  15.4  315  26 13   7.1   3.9
 10000  -8.2  17.2  270  18  9   6.5   3.6 |  -8.7  16.3  310  26 13   6.9   3.8
  9750  -7.8  18.0  270  18  9   6.0   3.3 |  -8.2  17.2  310  26 13   6.6   3.6
  9500  -7.3  18.9  270  18  9   6.4   3.5 |  -7.7  18.1  310  26 13   7.0   3.8
  9250  -6.8  19.8  270  18  9   7.3   4.0 |  -7.1  19.2  310  24 12   7.5   4.1
  9000  -6.3  20.7  270  18  9   7.3   4.0 |  -6.6  20.1  310  23 12   7.2   3.9
  8750  -5.8  21.6  265  19 10   6.3   3.5 |  -6.1  21.0  305  21 11   6.5   3.5
  8500  -5.3  22.5  265  19 10   6.5   3.5 |  -5.6  21.9  305  20 10   7.1   3.9
  8250  -4.8  23.4  265  19 10   7.1   3.9 |  -5.1  22.8  300  18 10   8.0   4.4
  8000  -4.3  24.3  265  20 10   7.0   3.9 |  -4.5  23.9  295  17  9   7.7   4.2
  7750  -3.8  25.2  265  20 10   6.3   3.4 |  -4.0  24.8  290  17  9   6.1   3.4
  7500  -3.4  25.9  265  20 10   5.7   3.1 |  -3.6  25.5  285  16  8   6.0   3.3
  7250  -2.9  26.8  270  18  9   5.9   3.3 |  -3.1  26.4  280  17  9   7.1   3.9
  7000  -2.5  27.5  270  17  9   5.8   3.2 |  -2.6  27.3  280  17  9   6.7   3.7
  6750  -2.1  28.2  270  15  8   5.8   3.2 |  -2.1  28.2  275  16  8   6.4   3.5
  6500  -1.7  28.9  270  13  7   6.4   3.5 |  -1.7  28.9  275  15  8   6.4   3.5
  6250  -1.2  29.8  275  11  6   7.0   3.9 |  -1.2  29.8  275  13  7   6.3   3.5
  6000  -0.7  30.7  275   9  5   6.7   3.7 |  -0.8  30.6  270  11  6   6.8   3.7
  5750  -0.2  31.6  280   8  4  10.2   5.6 |  -0.2  31.6  275  10  5   8.1   4.4
  5500   0.8  33.4  280   8  4  16.3   8.9 |   0.4  32.7  270   9  5   8.8   4.8
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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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