Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 311252
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0552 MST Saturday, January 31, 2015

This forecast is for Saturday, January 31, 2015:

If the trigger temperature of 50.8 F/10.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7036 ft MSL (2197 ft AGL)

Forecast maximum temperature................... 44.0 F/7.1 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 02/01....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:21:37 / 17:32:35 MST
Total possible sunshine........... 10 hr 10 min 58 sec (610 min 58 sec)
Altitude of sun at 12:27:28 MST... 33.63 degrees

Upper air data from rawinsonde observation taken on 01/31/2015 at 0500 MST

Freezing level.................. 7298 ft MSL (2459 ft AGL)
Convective condensation level... 8420 ft MSL (3581 ft AGL)
Lifted condensation level....... 7189 ft MSL (2350 ft AGL)
Lifted index.................... +9.4
K index......................... +20.1

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   265   29   15   2.0   1.1  102.8 217.1    54.8      M    M
 45000  -53.5 -64.3   260   34   17  -0.5  -0.3   87.1 188.8    49.1      M    M
 40000  -53.7 -64.7   230   37   19   0.2   0.1   63.4 146.1    37.0      M    M
 38000  -55.5 -67.9   195   41   21  -6.0  -3.3   51.8 125.2    30.2      M    M
 36000  -55.5 -67.9   205   48   25  -1.1  -0.6   42.2 108.0    24.5      M    M
 34000  -53.9 -65.0   210   72   37   6.1   3.4   36.1  97.1    20.9      M    M
 32000  -49.7 -57.5   210   50   26   8.4   4.6   33.7  92.7    19.7      M    M
 30000  -44.2 -47.6   220   33   17  10.1   5.5   33.3  91.9    19.9      M    M
 29000  -41.3 -42.3   215   26   13   9.5   5.2   33.1  91.6    20.0      M    M
 28000  -38.5 -37.3   200   19   10   9.5   5.2   33.1  91.6    20.2      M    M
 27000  -35.8 -32.4   205   19   10   8.7   4.8   32.8  91.0    20.2      M    M
 26000  -33.2 -27.8   210   18    9   8.8   4.8   32.4  90.3    20.2      M    M
 25000  -30.7 -23.3   215   18    9   8.1   4.5   31.9  89.4    20.0      M    M
 24000  -28.3 -18.9   215   17    9   8.2   4.5   31.3  88.3    19.7      M    M
 23000  -26.0 -14.8   220   16    8   7.5   4.1   30.4  86.7    19.2      M    M
 22000  -23.8 -10.8   225   15    8   7.5   4.1   29.5  85.2    18.7      M    M
 21000  -21.6  -6.9   230   14    7   7.5   4.1   28.8  83.8    18.3      M    M
 20000  -19.4  -2.9   235   13    7   7.5   4.1   28.2  82.7    17.9      M    M
 19500  -18.2  -0.8   230   13    7   7.5   4.1   27.8  82.0    17.6      M    M
 19000  -16.6   2.1   225   14    7   7.5   4.1   27.1  80.9    17.2      M    M
 18500  -15.4   4.3   220   15    8   7.3   4.0   26.8  80.2    17.0      M    M
 18000  -14.6   5.7   220   15    8   4.9   2.7   26.1  78.9    16.5      M    M
 17500  -13.9   7.0   215   15    8   5.0   2.8   25.3  77.5    15.8      M    M
 17000  -13.1   8.4   215   14    7   5.1   2.8   24.5  76.1    15.2      M    M
 16500  -12.4   9.7   220   11    6   5.1   2.8   23.7  74.6    14.6      M    M
 16000  -11.7  10.9   230    9    5   5.1   2.8   22.9  73.2    13.9      M    M
 15500  -10.9  12.4   225    8    4   5.1   2.8   22.0  71.7    13.2      M    M
 15000  -10.2  13.6   215    7    4   5.1   2.8   21.2  70.2    12.6      M    M
 14500   -9.4  15.1   210    6    3   5.0   2.7   20.4  68.8    11.9      M    M
 14000   -8.7  16.3   200    6    3   3.2   1.7   19.7  67.4    11.3      M    M
 13500   -8.5  16.7   210    8    4   1.6   0.9   18.3  64.9    10.1      M    M
 13000   -8.3  17.1   215   10    5   3.7   2.0   16.9  62.4     8.9      M    M
 12500   -7.4  18.7   220   12    6   6.4   3.5   16.3  61.4     8.4      M    M
 12000   -6.4  20.5   225   13    7   6.5   3.6   15.8  60.5     7.9      M    M
 11500   -5.5  22.1   215   11    6   6.5   3.6   15.3  59.5     7.4      M    M
 11000   -4.6  23.7   200    9    5   5.6   3.1   14.8  58.6     6.9      M    M
 10500   -3.9  25.0   180    8    4   4.4   2.4   13.9  57.0     6.1      M    M
 10250   -3.6  25.5   170    8    4   4.3   2.4   13.5  56.3     5.7      M    M
 10000   -3.3  26.1   160    9    4   4.5   2.4   13.1  55.5     5.3      M    M
  9750   -2.9  26.8   160    8    4   4.9   2.7   12.7  54.8     5.0      M    M
  9500   -2.6  27.3   170    6    3   5.1   2.8   12.3  54.1     4.6      M    M
  9250   -2.2  28.0   195    4    2   5.0   2.8   11.9  53.4     4.3      M    M
  9000   -1.9  28.6   230    4    2   5.0   2.8   11.5  52.8     3.9      M    M
  8750   -1.5  29.3   250    5    2   5.1   2.8   11.2  52.1     3.5      M    M
  8500   -1.1  30.0   260    6    3   5.0   2.7   10.8  51.4     3.2      M    M
  8250   -0.8  30.6   270    7    4   5.3   2.9   10.4  50.7     2.8      M    M
  8000   -0.4  31.3   275    9    5   3.9   2.1   10.1  50.1     2.5      M    M
  7750   -0.2  31.6   280    7    4   1.6   0.9    9.5  49.1     1.9      M    M
  7500   -0.1  31.8   290    4    2   1.4   0.8    8.8  47.9     1.3      M    M
  7250   -0.0  32.0   320    2    1   1.5   0.8    8.2  46.7     0.7      M    M
  7000    0.1  32.2   025    3    1   1.2   0.7    7.6  45.6     0.0      M    M
  6750    0.3  32.5   025    3    2   4.6   2.5    7.0  44.6    -0.5    149  0.8
  6500    0.8  33.4   015    3    2   7.3   4.0    6.7  44.1    -0.8    127  0.6
  6250    1.2  34.2   010    4    2   6.5   3.6    6.5  43.7    -1.0    105  0.5
  6000    1.7  35.1   360    4    2   6.7   3.7    6.3  43.3    -1.3     84  0.4
  5750    2.2  36.0   350    3    2   6.7   3.7    6.0  42.9    -1.5     62  0.3
  5500    2.7  36.9   335    3    1   6.7   3.7    5.8  42.5    -1.8     40  0.2
  5250    3.1  37.6   315    2    1   6.7   3.7    5.6  42.0    -2.1     18  0.1
  5000    3.6  38.5   290    3    1   6.9   3.8    5.4  41.6    -2.3      M    M

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

           01/31/2015 at 0800 MST          |       01/31/2015 at 1100 MST
                                           |
K index... +18.6  LI... +4.7               | K index... +18.7  LI... +4.1
CAPE... 0.0  CIN... -1.0                   | CAPE... 0.0  CIN... M
                                           |
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 -58.7 -73.7  260  25 13   3.5   1.9 | -58.7 -73.7  260  30 16   3.5   1.9
 45000 -53.4 -64.1  250  33 17   2.1   1.1 | -53.3 -63.9  260  41 21   2.2   1.2
 40000 -53.1 -63.6  235  30 15   0.2   0.1 | -52.0 -61.6  245  31 16   0.9   0.5
 38000 -53.1 -63.6  230  28 15  -0.1  -0.1 | -52.2 -62.0  245  26 14  -1.8  -1.0
 36000 -53.2 -63.8  230  26 14  -0.1  -0.1 | -53.2 -63.8  250  19 10  -1.8  -1.0
 34000 -52.8 -63.0  235  24 12   5.6   3.1 | -54.2 -65.6  265  12  6   2.8   1.5
 32000 -49.8 -57.6  240  23 12   5.0   2.7 | -50.1 -58.2  295  12  6   6.1   3.3
 30000 -46.3 -51.3  250  22 11   9.9   5.4 | -46.1 -51.0  310  13  6   9.5   5.2
 29000 -43.4 -46.1  250  20 10   9.6   5.3 | -43.3 -45.9  305  12  6   9.4   5.1
 28000 -40.5 -40.9  250  18  9   9.6   5.3 | -40.5 -40.9  300  12  6   9.4   5.1
 27000 -37.6 -35.7  250  16  8   9.6   5.3 | -37.7 -35.9  295  12  6   9.4   5.1
 26000 -34.8 -30.6  250  14  7   9.6   5.3 | -34.9 -30.8  290  11  6   9.3   5.1
 25000 -31.9 -25.4  245  12  6   9.6   5.3 | -32.1 -25.8  285  11  6   9.3   5.1
 24000 -29.0 -20.2  235  10  5   9.8   5.4 | -29.3 -20.7  280  11  5   9.5   5.2
 23000 -26.6 -15.9  235   9  5   7.6   4.2 | -26.9 -16.4  280  10  5   7.8   4.3
 22000 -24.4 -11.9  240  10  5   7.6   4.2 | -24.6 -12.3  285  10  5   7.8   4.3
 21000 -22.1  -7.8  240  10  5   7.5   4.1 | -22.3  -8.1  290  10  5   7.5   4.1
 20000 -19.9  -3.8  245  10  5   7.3   4.0 | -20.3  -4.5  295  10  5   6.6   3.6
 19500 -18.9  -2.0  245  11  6   7.3   4.0 | -19.3  -2.7  300  10  5   6.6   3.6
 19000 -17.8  -0.0  245  11  6   7.3   4.0 | -18.4  -1.1  300  10  5   6.6   3.6
 18500 -16.7   1.9  245  12  6   7.3   4.0 | -17.4   0.7  300  11  5   6.6   3.6
 18000 -15.7   3.7  245  12  6   6.3   3.5 | -16.5   2.3  305  11  6   6.1   3.3
 17500 -14.8   5.4  245  12  6   6.4   3.5 | -15.6   3.9  305  11  6   6.1   3.4
 17000 -13.8   7.2  250  12  6   6.0   3.3 | -14.7   5.5  310  11  6   5.9   3.2
 16500 -13.0   8.6  250  11  6   5.9   3.2 | -13.8   7.2  310  11  6   5.8   3.2
 16000 -12.1  10.2  255  10  5   5.7   3.1 | -13.0   8.6  315  11  6   5.8   3.2
 15500 -10.9  12.4  260   9  5   5.3   2.9 | -11.7  10.9  320  11  5   5.7   3.1
 15000 -10.2  13.6  260   9  4   5.0   2.7 | -10.9  12.4  325  11  5   5.4   3.0
 14500  -9.5  14.9  260   8  4   4.8   2.6 | -10.1  13.8  325  10  5   5.3   2.9
 14000  -8.8  16.2  265   7  4   4.4   2.4 |  -9.4  15.1  330  10  5   5.2   2.8
 13500  -8.2  17.2  265   7  3   3.7   2.0 |  -8.6  16.5  335  10  5   5.0   2.7
 13000  -7.7  18.1  270   6  3   3.8   2.1 |  -7.9  17.8  335   9  5   4.9   2.7
 12500  -7.1  19.2  270   6  3   4.3   2.4 |  -7.2  19.0  335   9  4   4.7   2.6
 12000  -6.4  20.5  265   5  3   4.3   2.4 |  -6.5  20.3  335   8  4   4.7   2.6
 11500  -5.8  21.6  270   6  3   4.6   2.5 |  -5.8  21.6  335   8  4   5.0   2.7
 11000  -5.1  22.8  275   6  3   4.5   2.4 |  -5.1  22.8  335   8  4   4.7   2.6
 10500  -4.5  23.9  280   7  3   3.6   2.0 |  -4.5  23.9  330   8  4   3.4   1.9
 10250  -4.3  24.3  285   7  4   3.9   2.1 |  -4.3  24.3  325   8  4   4.0   2.2
 10000  -3.9  25.0  285   7  4   5.4   2.9 |  -3.9  25.0  325   8  4   5.4   2.9
  9750  -3.5  25.7  285   8  4   5.4   2.9 |  -3.5  25.7  320   8  4   4.9   2.7
  9500  -3.2  26.2  290   8  4   4.4   2.4 |  -3.2  26.2  315   9  4   4.0   2.2
  9250  -2.9  26.8  290   8  4   4.8   2.6 |  -2.9  26.8  315   9  5   4.2   2.3
  9000  -2.5  27.5  290   9  4   4.2   2.3 |  -2.6  27.3  310   9  5   4.3   2.3
  8750  -2.2  28.0  290   9  4   4.0   2.2 |  -2.3  27.9  305   9  5   4.3   2.4
  8500  -1.9  28.6  295   9  5   4.3   2.4 |  -2.0  28.4  305   9  5   4.1   2.3
  8250  -1.6  29.1  295   9  5   4.3   2.4 |  -1.7  28.9  305   9  5   4.4   2.4
  8000  -1.3  29.7  295   9  5   4.2   2.3 |  -1.4  29.5  305   9  5   4.6   2.5
  7750  -1.0  30.2  295   9  4   3.7   2.0 |  -1.1  30.0  305   8  4   4.1   2.2
  7500  -0.8  30.6  295   8  4   3.6   2.0 |  -0.8  30.6  305   8  4   4.0   2.2
  7250  -0.5  31.1  295   8  4   3.3   1.8 |  -0.5  31.1  305   7  4   3.4   1.8
  7000  -0.3  31.5  300   7  3   2.7   1.5 |  -0.3  31.5  305   6  3   2.8   1.5
  6750  -0.1  31.8  300   6  3   1.7   1.0 |  -0.1  31.8  300   5  2   2.4   1.3
  6500  -0.0  32.0  305   5  2   1.4   0.8 |   0.1  32.2  295   4  2   4.1   2.3
  6250   0.1  32.2  305   4  2   2.2   1.2 |   0.6  33.1  280   3  1   7.6   4.2
  6000   0.3  32.5  310   3  1   2.5   1.3 |   1.2  34.2  265   3  1   8.6   4.7
  5750   0.5  32.9  320   2  1   2.9   1.6 |   1.8  35.2  250   3  1   9.2   5.0
  5500   0.8  33.4  320   1  1   4.3   2.4 |   2.5  36.5  250   2  1   9.5   5.2
  5250   1.1  34.0  320   1  1   5.7   3.1 |   3.2  37.8  250   2  1   8.8   4.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/31/2015 at 1400 MST          |       01/31/2015 at 1700 MST
                                           |
K index... +19.1  LI... +3.1               | K index... +4.1  LI... +4.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -58.4 -73.1  265  31 16   3.2   1.7 | -58.4 -73.1  270  33 17   3.1   1.7
 45000 -53.6 -64.5  270  37 19   2.2   1.2 | -53.6 -64.5  275  34 17   1.9   1.0
 40000 -52.1 -61.8  270  32 16   1.0   0.5 | -53.5 -64.3  285  29 15   0.0   0.0
 38000 -52.2 -62.0  270  28 14  -2.1  -1.1 | -53.6 -64.5  305  28 15  -0.4  -0.2
 36000 -53.5 -64.3  280  22 12  -2.0  -1.1 | -53.8 -64.8  335  35 18  -0.4  -0.2
 34000 -54.7 -66.5  295  18  9   2.5   1.4 | -54.0 -65.2  350  48 24   3.4   1.9
 32000 -50.2 -58.4  305  16  8   6.6   3.6 | -50.5 -58.9  350  45 23   5.8   3.2
 30000 -46.0 -50.8  320  16  8   9.1   5.0 | -46.2 -51.2  350  41 21   9.0   4.9
 29000 -43.3 -45.9  325  18  9   8.9   4.9 | -43.6 -46.5  355  40 21   8.8   4.8
 28000 -40.6 -41.1  335  21 11   9.0   4.9 | -40.9 -41.6  355  39 20   8.8   4.8
 27000 -37.9 -36.2  340  24 12   8.9   4.9 | -38.3 -36.9  355  38 19   8.8   4.8
 26000 -35.3 -31.5  340  26 13   8.9   4.9 | -35.7 -32.3  355  37 19   8.6   4.7
 25000 -32.6 -26.7  335  28 14   8.9   4.9 | -33.1 -27.6  360  37 19   8.6   4.7
 24000 -29.9 -21.8  335  29 15   9.0   4.9 | -30.5 -22.9  360  37 19   8.7   4.8
 23000 -27.4 -17.3  335  28 14   8.1   4.5 | -28.2 -18.8  005  37 19   7.5   4.1
 22000 -25.0 -13.0  340  26 13   8.1   4.5 | -26.0 -14.8  005  37 19   7.5   4.1
 21000 -22.6  -8.7  340  24 12   7.7   4.2 | -23.7 -10.7  010  37 19   7.5   4.1
 20000 -20.6  -5.1  345  23 12   6.6   3.6 | -21.5  -6.7  005  35 18   7.5   4.1
 19500 -19.6  -3.3  345  23 12   6.6   3.6 | -20.4  -4.7  005  34 18   7.5   4.1
 19000 -18.7  -1.7  345  23 12   6.6   3.6 | -19.2  -2.6  005  34 17   7.5   4.1
 18500 -17.7   0.1  345  23 12   6.6   3.6 | -18.1  -0.6  005  33 17   7.4   4.1
 18000 -16.8   1.8  350  22 11   5.9   3.2 | -17.0   1.4  005  33 17   7.3   4.0
 17500 -15.9   3.4  350  22 11   5.9   3.3 | -15.9   3.4  360  33 17   7.4   4.0
 17000 -15.0   5.0  350  21 11   5.9   3.2 | -14.9   5.2  360  33 17   6.2   3.4
 16500 -14.2   6.4  350  21 11   5.9   3.2 | -14.0   6.8  360  32 17   5.9   3.3
 16000 -13.3   8.1  350  20 10   6.0   3.3 | -13.1   8.4  005  32 16   5.8   3.2
 15500 -12.4   9.7  350  19 10   6.3   3.5 | -12.3   9.9  005  31 16   5.5   3.0
 15000 -11.0  12.2  355  17  9   6.2   3.4 | -11.5  11.3  005  29 15   5.7   3.1
 14500 -10.1  13.8  360  17  9   6.1   3.3 | -10.2  13.6  360  27 14   6.2   3.4
 14000  -9.2  15.4  360  16  8   5.9   3.2 |  -9.3  15.3  360  25 13   5.8   3.2
 13500  -8.4  16.9  005  15  8   5.6   3.1 |  -8.6  16.5  355  23 12   5.2   2.8
 13000  -7.6  18.3  010  15  8   5.5   3.0 |  -7.9  17.8  355  22 11   5.0   2.7
 12500  -6.8  19.8  010  14  7   5.2   2.9 |  -7.2  19.0  355  21 11   4.4   2.4
 12000  -6.1  21.0  015  13  7   5.2   2.8 |  -6.6  20.1  355  20 10   4.5   2.5
 11500  -5.3  22.5  015  12  6   4.8   2.7 |  -6.0  21.2  355  18  9   4.4   2.4
 11000  -4.6  23.7  015  12  6   4.5   2.5 |  -5.4  22.3  360  17  9   4.5   2.5
 10500  -4.1  24.6  010  10  5   3.2   1.8 |  -4.7  23.5  360  16  8   4.5   2.4
 10250  -3.9  25.0  010  10  5   3.7   2.0 |  -4.3  24.3  005  15  8   5.8   3.2
 10000  -3.6  25.5  010   9  5   4.8   2.6 |  -3.9  25.0  005  15  7   7.2   4.0
  9750  -3.2  26.2  005   9  4   4.9   2.7 |  -3.4  25.9  005  14  7   6.3   3.4
  9500  -2.9  26.8  005   8  4   4.4   2.4 |  -2.9  26.8  005  13  7   5.9   3.2
  9250  -2.5  27.5  360   8  4   4.6   2.6 |  -2.5  27.5  005  13  7   6.0   3.3
  9000  -2.2  28.0  355   7  4   3.7   2.0 |  -2.1  28.2  005  12  6   5.7   3.1
  8750  -2.0  28.4  355   7  3   3.7   2.0 |  -1.7  28.9  360  11  6   5.4   3.0
  8500  -1.6  29.1  345   6  3   4.4   2.4 |  -1.3  29.7  360  11  5   5.6   3.1
  8250  -1.3  29.7  340   6  3   4.6   2.5 |  -0.9  30.4  355  10  5   5.1   2.8
  8000  -1.0  30.2  335   6  3   5.1   2.8 |  -0.6  30.9  350   9  5   4.1   2.3
  7750  -0.6  30.9  325   5  3   4.5   2.5 |  -0.3  31.5  340   8  4   4.4   2.4
  7500  -0.3  31.5  310   5  2   2.8   1.5 |   0.1  32.2  335   7  4   4.2   2.3
  7250  -0.1  31.8  295   5  2   7.0   3.8 |   0.4  32.7  325   7  4   6.8   3.8
  7000   0.6  33.1  285   5  2  11.0   6.0 |   1.0  33.8  320   6  3   9.4   5.1
  6750   1.4  34.5  275   5  3   9.1   5.0 |   1.7  35.1  315   6  3   8.1   4.4
  6500   2.0  35.6  270   5  3   9.5   5.2 |   2.3  36.1  315   6  3   8.9   4.9
  6250   2.8  37.0  270   5  3  10.9   6.0 |   3.0  37.4  310   6  3  10.5   5.8
  6000   3.6  38.5  270   5  3  11.1   6.1 |   3.8  38.8  305   5  3  10.6   5.8
  5750   4.4  39.9  270   5  3  10.3   5.7 |   4.5  40.1  305   5  3   9.0   5.0
  5500   5.1  41.2  270   5  2   9.8   5.4 |   5.1  41.2  305   5  2   6.3   3.4
  5250   5.9  42.6  270   5  3  10.0   5.5 |   5.5  41.9  305   5  2   4.6   2.5
  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 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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