Soaring Guidance
Issued by NWS Grand Junction, CO

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822
UXUS97 KGJT 261242
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0542 MST Sunday, February 26, 2017

This forecast is for Sunday, February 26, 2017:

If the trigger temperature of 33.7 F/0.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 963 ft/min (4.9 m/s)
   Maximum height of thermals.................. 15766 ft MSL (10927 ft AGL)

Forecast maximum temperature................... 42.0 F/6.0 C
Time of trigger temperature.................... 1015 MST
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................. 12151 ft MSL (7311 ft AGL)
Thermal soaring outlook for Monday 02/27....... Good

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

Remarks...

Sunrise/Sunset.................... 06:50:24 / 18:02:43 MST
Total possible sunshine........... 11 hr 12 min 19 sec (672 min 19 sec)
Altitude of sun at 12:26:49 MST... 42.49 degrees

Upper air data from rawinsonde observation taken on 02/26/2017 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 14914 ft MSL (10075 ft AGL)
Lifted condensation level....... 15472 ft MSL (10633 ft AGL)
Lifted index.................... +10.5
K index......................... -14.8

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  -55.5 -67.9   265   53   27  -0.8  -0.4  114.3 237.7    61.1      M    M
 45000  -53.1 -63.6   265   58   30   7.0   3.8   92.1 197.7    52.1      M    M
 40000  -50.9 -59.6   265   67   35   6.0   3.3   72.1 161.8    42.9      M    M
 38000  -53.1 -63.6   270   57   30   0.9   0.5   59.7 139.4    35.8      M    M
 36000  -52.5 -62.5   270   56   29   1.3   0.7   51.9 125.4    31.5      M    M
 34000  -52.4 -62.3   270   45   23   1.2   0.7   43.6 110.5    26.5      M    M
 32000  -53.0 -63.4   280   28   14   0.5   0.3   33.4  92.1    20.0      M    M
 30000  -51.6 -60.9   335   14    7  -5.7  -3.1   27.3  81.2    16.0      M    M
 29000  -50.4 -58.7   360   15    8   7.7   4.2   25.0  77.0    14.5      M    M
 28000  -48.1 -54.6   025   12    6   7.5   4.1   24.2  75.6    14.1      M    M
 27000  -45.8 -50.4   030   14    7   8.0   4.4   23.3  74.0    13.6      M    M
 26000  -43.4 -46.1   035   16    8   8.1   4.4   22.7  72.8    13.3      M    M
 25000  -41.0 -41.8   040   18    9   8.1   4.4   22.2  71.9    13.1      M    M
 24000  -38.6 -37.5   050   14    7   8.1   4.4   21.5  70.8    12.7      M    M
 23000  -36.4 -33.5   040   13    7  -3.1  -1.7   20.6  69.0    12.1      M    M
 22000  -35.6 -32.1   015    6    3   6.9   3.8   17.9  64.2    10.1      M    M
 21000  -34.3 -29.7   300    6    3  -0.7  -0.4   15.9  60.7     8.6      M    M
 20000  -33.0 -27.4   280   10    5   5.6   3.1   14.0  57.2     7.1      M    M
 19500  -32.2 -26.0   285   15    8   5.3   2.9   13.2  55.8     6.5      M    M
 19000  -31.3 -24.3   285   22   11   1.2   0.6   12.5  54.5     5.9      M    M
 18500  -31.9 -25.4   275   26   13  -3.6  -2.0   10.1  50.2     3.9      M    M
 18000  -31.6 -24.9   265   31   16   6.9   3.8    8.8  47.8     2.7      M    M
 17500  -30.7 -23.3   255   32   17   5.6   3.1    8.1  46.5     2.1      M    M
 17000  -29.6 -21.3   255   34   18   4.2   2.3    6.8  44.3     1.1      M    M
 16500  -28.8 -19.8   255   35   18   7.7   4.2    6.1  42.9     0.4      M    M
 16000  -27.6 -17.7   255   36   18   6.7   3.7    5.8  42.5     0.2      M    M
 15500  -26.8 -16.2   260   34   18   5.6   3.1    5.1  41.2    -0.4    934  4.7
 15000  -25.9 -14.6   265   33   17   6.7   3.7    4.5  40.1    -1.0    892  4.5
 14500  -24.9 -12.8   265   32   16   8.1   4.5    4.0  39.2    -1.5    848  4.3
 14000  -23.4 -10.1   270   31   16   9.4   5.2    4.0  39.1    -1.5    790  4.0
 13500  -22.0  -7.6   270   27   14   9.0   4.9    3.9  39.1    -1.6    733  3.7
 13000  -20.8  -5.4   275   24   12   6.6   3.6    3.6  38.5    -1.8    682  3.5
 12500  -20.0  -4.0   275   20   10   5.1   2.8    2.9  37.2    -2.5    644  3.3
 12000  -19.3  -2.7   280   17    9   5.4   3.0    2.1  35.9    -3.3    607  3.1
 11500  -18.2  -0.8   280   14    7   8.7   4.8    1.7  35.1    -3.6    559  2.8
 11000  -16.8   1.8   280   12    6   8.8   4.8    1.6  34.8    -3.8    504  2.6
 10500  -15.5   4.1   280   12    6   8.6   4.7    1.4  34.5    -3.9    450  2.3
 10250  -14.9   5.2   280   12    6   9.4   5.2    1.3  34.4    -4.0    422  2.1
 10000  -14.1   6.6   280   12    6  10.9   6.0    1.4  34.5    -4.0    392  2.0
  9750  -13.3   8.1   280   12    6   9.6   5.3    1.5  34.6    -3.9    361  1.8
  9500  -12.7   9.1   275   12    6   8.2   4.5    1.4  34.4    -4.0    334  1.7
  9250  -12.0  10.4   270   11    6   8.9   4.9    1.3  34.3    -4.1    308  1.6
  9000  -11.4  11.5   265   11    6   7.6   4.2    1.2  34.1    -4.2    281  1.4
  8750  -10.9  12.4   265   10    5   5.6   3.1    0.9  33.6    -4.5    259  1.3
  8500  -10.5  13.1   265    9    5   5.8   3.2    0.6  33.1    -4.8    240  1.2
  8250  -10.1  13.8   260    8    4   6.8   3.8    0.3  32.6    -5.1    219  1.1
  8000   -9.5  14.9   260    7    4   7.6   4.2    0.1  32.2    -5.4    196  1.0
  7750   -9.0  15.8   265    7    3   8.1   4.5   -0.0  32.0    -5.5    172  0.9
  7500   -8.3  17.1   270    6    3   8.4   4.6   -0.1  31.8    -5.7    145  0.7
  7250   -7.7  18.1   275    6    3   8.3   4.6   -0.2  31.6    -5.8    119  0.6
  7000   -7.1  19.2   280    6    3   8.3   4.6   -0.3  31.4    -5.9     93  0.5
  6750   -6.5  20.3   280    5    3   8.2   4.5   -0.5  31.2    -6.0     67  0.3
  6500   -5.8  21.6   285    5    2   7.9   4.3   -0.6  30.9    -6.2     42  0.2
  6250   -5.3  22.5   290    4    2   7.8   4.3   -0.7  30.7    -6.3     17  0.1
  6000   -4.7  23.5   295    3    2   7.6   4.2   -0.9  30.4    -6.5      M    M
  5750   -4.1  24.6   310    3    1   8.6   4.7   -1.0  30.2    -6.7      M    M
  5500   -3.6  25.5   335    3    1   4.8   2.6   -1.2  29.9    -6.9      M    M
  5250   -3.4  25.9   355    3    2   1.6   0.9   -1.8  28.8    -7.5      M    M
  5000   -3.3  26.1   010    4    2  -1.3  -0.7   -2.4  27.7    -8.1      M    M

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

           02/26/2017 at 0800 MST          |       02/26/2017 at 1100 MST
                                           |
K index... -8.8  LI... +7.6                | K index... -10.5  LI... +8.8
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 -55.2 -67.4  265  48 25   1.4   0.7 | -55.7 -68.3  260  49 25   1.4   0.8
 45000 -53.1 -63.6  270  57 29   1.4   0.7 | -53.5 -64.3  265  55 28   1.4   0.8
 40000 -54.1 -65.4  275  52 27  -1.2  -0.6 | -56.5 -69.7  275  52 27  -2.8  -1.5
 38000 -54.8 -66.6  275  49 25  -0.9  -0.5 | -58.2 -72.8  275  50 26  -1.0  -0.6
 36000 -54.9 -66.8  280  39 20  -0.0  -0.0 | -57.2 -71.0  285  43 22   1.6   0.9
 34000 -54.9 -66.8  295  30 16  -0.1  -0.0 | -56.3 -69.3  295  38 19   1.6   0.9
 32000 -53.6 -64.5  310  23 12   3.7   2.0 | -54.1 -65.4  305  32 17   4.8   2.6
 30000 -51.4 -60.5  345  19 10   3.7   2.0 | -51.3 -60.3  315  27 14   4.8   2.6
 29000 -49.4 -56.9  355  19 10   7.5   4.1 | -49.5 -57.1  320  25 13   8.0   4.4
 28000 -47.1 -52.8  360  19 10   7.7   4.2 | -46.6 -51.9  325  23 12   7.8   4.3
 27000 -44.8 -48.6  360  19 10   7.7   4.2 | -44.2 -47.6  325  22 11   7.8   4.3
 26000 -42.5 -44.5  005  18 10   7.5   4.1 | -41.9 -43.4  325  21 11   7.6   4.2
 25000 -40.2 -40.4  005  16  8   7.5   4.1 | -39.6 -39.3  325  19 10   7.6   4.1
 24000 -38.0 -36.4  010  13  7   7.5   4.1 | -37.4 -35.3  325  17  9   7.6   4.1
 23000 -35.8 -32.4  015  10  5   6.5   3.6 | -35.2 -31.4  320  15  8   6.7   3.7
 22000 -34.0 -29.2  010   9  5   5.9   3.3 | -33.2 -27.8  315  13  7   6.6   3.6
 21000 -32.2 -26.0  005   8  4   5.9   3.3 | -31.2 -24.2  310  10  5   6.6   3.6
 20000 -30.5 -22.9  350   7  4   4.7   2.6 | -29.3 -20.7  300   9  5   5.8   3.2
 19500 -29.8 -21.6  335   8  4   4.8   2.6 | -28.5 -19.3  300   9  5   5.8   3.2
 19000 -29.1 -20.4  325   9  5   4.8   2.6 | -27.6 -17.7  300  10  5   5.8   3.2
 18500 -28.4 -19.1  315  10  5   4.8   2.6 | -26.7 -16.1  295  10  5   5.8   3.2
 18000 -27.6 -17.7  305  12  6   5.1   2.8 | -25.8 -14.4  295  10  5   5.4   3.0
 17500 -27.3 -17.1  295  15  8   0.4   0.2 | -25.4 -13.7  290  12  6   1.0   0.5
 17000 -27.1 -16.8  285  19 10   0.8   0.4 | -25.2 -13.4  290  15  8   1.3   0.7
 16500 -26.9 -16.4  280  23 12   2.3   1.3 | -25.0 -13.0  285  19 10   1.5   0.8
 16000 -26.5 -15.7  280  25 13   2.9   1.6 | -24.8 -12.6  285  21 11   1.5   0.8
 15500 -26.1 -15.0  275  27 14   4.2   2.3 | -24.6 -12.3  280  24 12   2.8   1.5
 15000 -25.2 -13.4  275  27 14   5.8   3.2 | -24.0 -11.2  280  25 13   3.7   2.0
 14500 -24.4 -11.9  275  28 14   6.3   3.5 | -23.5 -10.3  280  26 13   4.4   2.4
 14000 -22.8  -9.0  275  27 14   7.3   4.0 | -22.7  -8.9  280  26 13   5.6   3.1
 13500 -21.7  -7.1  275  27 14   7.5   4.1 | -21.4  -6.5  275  25 13   7.0   3.8
 13000 -20.6  -5.1  280  26 13   7.6   4.1 | -20.3  -4.5  275  23 12   7.1   3.9
 12500 -19.5  -3.1  280  25 13   7.6   4.1 | -19.3  -2.7  270  22 11   7.4   4.1
 12000 -18.3  -0.9  280  24 12   7.6   4.2 | -18.2  -0.8  270  20 11   7.5   4.1
 11500 -17.2   1.0  280  22 11   7.0   3.8 | -17.0   1.4  265  19 10   7.9   4.3
 11000 -16.2   2.8  280  20 10   7.0   3.9 | -15.9   3.4  260  17  9   7.9   4.3
 10500 -15.3   4.5  280  17  9   5.2   2.9 | -14.7   5.5  255  16  8   7.6   4.2
 10250 -14.9   5.2  275  15  8   4.7   2.6 | -14.2   6.4  250  15  8   7.0   3.9
 10000 -14.5   5.9  275  14  7   6.7   3.7 | -13.6   7.5  245  15  7   9.3   5.1
  9750 -13.9   7.0  270  12  6   7.8   4.3 | -12.8   9.0  245  14  7   9.3   5.1
  9500 -13.4   7.9  265  11  5   6.5   3.6 | -12.3   9.9  240  13  7   7.0   3.8
  9250 -12.9   8.8  260   9  5   6.8   3.7 | -11.7  10.9  240  12  6   7.7   4.2
  9000 -12.4   9.7  250   8  4   6.9   3.8 | -11.2  11.8  235  11  6   7.1   3.9
  8750 -11.9  10.6  245   7  4   6.7   3.7 | -10.7  12.7  230  10  5   6.4   3.5
  8500 -11.4  11.5  240   6  3   6.3   3.5 | -10.2  13.6  230   9  5   6.2   3.4
  8250 -11.0  12.2  230   5  3   6.3   3.5 |  -9.8  14.4  225   8  4   6.2   3.4
  8000 -10.5  13.1  215   4  2   7.4   4.0 |  -9.3  15.3  220   7  4   5.8   3.2
  7750  -9.9  14.2  210   4  2   7.3   4.0 |  -8.9  16.0  210   6  3   6.3   3.4
  7500  -9.4  15.1  200   4  2   6.1   3.3 |  -8.4  16.9  205   5  3   6.2   3.4
  7250  -8.9  16.0  195   5  2   6.9   3.8 |  -8.0  17.6  195   5  2   8.2   4.5
  7000  -8.4  16.9  185   5  2   7.6   4.2 |  -7.2  19.0  195   5  2  11.1   6.1
  6750  -7.8  18.0  180   5  3   7.2   3.9 |  -6.4  20.5  195   4  2  10.0   5.5
  6500  -7.3  18.9  175   5  3   6.5   3.5 |  -5.7  21.7  195   4  2   9.6   5.3
  6250  -6.9  19.6  170   5  3   5.7   3.1 |  -4.9  23.2  200   4  2  11.0   6.0
  6000  -6.5  20.3  165   5  3   5.4   3.0 |  -4.1  24.6  200   4  2  11.3   6.2
  5750  -6.1  21.0  160   5  2   6.1   3.4 |  -3.3  26.1  200   4  2  10.4   5.7
  5500  -5.7  21.7  145   4  2   4.4   2.4 |  -2.5  27.5  200   4  2  11.2   6.1
  5250  -5.5  22.1  145   3  2   0.8   0.4 |  -1.6  29.1  200   4  2  13.5   7.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           02/26/2017 at 1400 MST          |       02/26/2017 at 1700 MST
                                           |
K index... -10.6  LI... +8.3               | K index... -9.5  LI... +7.5
CAPE... 0.0  CIN... -1.9                   | CAPE... 0.0  CIN... -5.2
                                           |
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 -55.7 -68.3  260  53 27   0.7   0.4 | -56.6 -69.9  265  54 28   0.8   0.4
 45000 -54.6 -66.3  265  56 29   0.7   0.4 | -55.4 -67.7  270  61 31   0.8   0.4
 40000 -57.1 -70.8  275  61 31  -2.2  -1.2 | -58.1 -72.6  270  66 34  -2.5  -1.4
 38000 -58.4 -73.1  275  62 32  -1.0  -0.5 | -59.7 -75.5  275  68 35   0.2   0.1
 36000 -58.3 -72.9  280  57 30   0.1   0.0 | -58.8 -73.8  280  62 32   1.4   0.8
 34000 -58.3 -72.9  280  53 27   0.1   0.1 | -58.0 -72.4  290  57 29   1.5   0.8
 32000 -55.5 -67.9  285  48 25   6.8   3.7 | -55.1 -67.2  290  54 28   6.2   3.4
 30000 -51.4 -60.5  290  43 22   6.8   3.8 | -51.4 -60.5  285  51 26   6.2   3.4
 29000 -49.3 -56.7  290  41 21   7.8   4.3 | -49.3 -56.7  285  50 26   7.8   4.3
 28000 -46.9 -52.4  290  39 20   7.8   4.3 | -46.9 -52.4  280  50 26   7.8   4.3
 27000 -44.0 -47.2  290  37 19   7.8   4.3 | -44.6 -48.3  280  49 25   7.8   4.3
 26000 -41.6 -42.9  290  35 18   8.1   4.4 | -41.6 -42.9  280  49 25   8.3   4.6
 25000 -39.2 -38.6  290  34 17   8.1   4.4 | -39.1 -38.4  280  48 25   8.3   4.5
 24000 -36.8 -34.2  290  32 17   8.1   4.4 | -36.7 -34.1  275  47 24   8.3   4.5
 23000 -34.4 -29.9  290  30 16   8.0   4.4 | -34.2 -29.6  275  46 23   8.3   4.5
 22000 -32.0 -25.6  285  28 15   8.0   4.4 | -31.7 -25.1  275  43 22   8.3   4.5
 21000 -29.5 -21.1  285  26 13   8.0   4.4 | -29.2 -20.6  275  40 21   8.2   4.5
 20000 -27.5 -17.5  280  24 12   5.5   3.0 | -26.9 -16.4  275  38 19   7.2   3.9
 19500 -26.7 -16.1  280  23 12   5.5   3.0 | -25.9 -14.6  275  36 19   7.2   3.9
 19000 -25.8 -14.4  275  21 11   5.5   3.0 | -24.8 -12.6  275  35 18   7.1   3.9
 18500 -25.0 -13.0  275  20 10   5.5   3.0 | -23.7 -10.7  275  34 17   7.1   3.9
 18000 -24.2 -11.6  270  19 10   4.9   2.7 | -22.7  -8.9  275  32 17   6.1   3.4
 17500 -23.6 -10.5  270  19 10   3.3   1.8 | -22.0  -7.6  270  31 16   4.4   2.4
 17000 -23.1  -9.6  270  20 10   3.5   1.9 | -21.3  -6.3  270  29 15   4.6   2.5
 16500 -22.7  -8.9  270  20 11   1.7   0.9 | -20.8  -5.4  270  28 14   2.3   1.3
 16000 -22.5  -8.5  270  22 11   1.8   1.0 | -20.4  -4.7  265  28 14   2.5   1.4
 15500 -22.2  -8.0  270  23 12   2.2   1.2 | -20.0  -4.0  265  27 14   2.5   1.3
 15000 -21.8  -7.2  270  24 13   2.5   1.4 | -19.7  -3.5  260  27 14   2.4   1.3
 14500 -21.5  -6.7  270  26 13   3.1   1.7 | -19.3  -2.7  260  27 14   2.3   1.3
 14000 -20.9  -5.6  265  26 13   3.8   2.1 | -19.0  -2.2  260  28 14   2.3   1.2
 13500 -20.3  -4.5  265  26 14   4.7   2.6 | -18.7  -1.7  255  29 15   3.7   2.1
 13000 -19.0  -2.2  260  27 14   6.2   3.4 | -17.8  -0.0  255  28 15   6.8   3.8
 12500 -17.9  -0.2  255  26 14   8.5   4.6 | -16.2   2.8  250  27 14   9.0   4.9
 12000 -16.7   1.9  255  26 13   8.5   4.7 | -14.9   5.2  245  26 13   9.2   5.0
 11500 -15.4   4.3  250  25 13   9.2   5.1 | -13.6   7.5  240  25 13   9.0   5.0
 11000 -14.0   6.8  250  23 12   9.4   5.2 | -12.2  10.0  240  23 12   9.3   5.1
 10500 -12.8   9.0  250  21 11   7.7   4.2 | -11.0  12.2  235  21 11   7.3   4.0
 10250 -12.2  10.0  245  20 10   7.3   4.0 | -10.5  13.1  235  19 10   7.1   3.9
 10000 -11.7  10.9  245  19 10   9.6   5.3 | -10.0  14.0  235  18  9   8.5   4.7
  9750 -10.9  12.4  245  18  9   9.0   4.9 |  -9.3  15.3  230  17  9   8.3   4.5
  9500 -10.4  13.3  245  16  8   6.2   3.4 |  -8.8  16.2  230  16  8   6.7   3.7
  9250  -9.9  14.2  245  15  7   7.1   3.9 |  -8.3  17.1  225  15  8   7.3   4.0
  9000  -9.4  15.1  240  13  7   6.3   3.5 |  -7.7  18.1  220  13  7   6.5   3.6
  8750  -9.0  15.8  240  11  5   5.0   2.8 |  -7.3  18.9  215  12  6   5.7   3.1
  8500  -8.6  16.5  240   8  4   4.7   2.6 |  -6.9  19.6  210  11  6   5.7   3.1
  8250  -8.3  17.1  240   6  3   4.6   2.5 |  -6.5  20.3  200  10  5   5.6   3.0
  8000  -7.9  17.8  240   4  2   7.6   4.2 |  -6.0  21.2  190   9  5   6.1   3.4
  7750  -7.2  19.0  240   4  2   9.8   5.4 |  -5.6  21.9  185   8  4   6.4   3.5
  7500  -6.5  20.3  240   4  2   8.7   4.8 |  -5.1  22.8  180   7  3   5.8   3.2
  7250  -5.8  21.6  240   3  2   9.8   5.4 |  -4.7  23.5  175   5  3   6.7   3.7
  7000  -5.1  22.8  240   3  2  10.8   5.9 |  -4.1  24.6  170   5  2   8.9   4.9
  6750  -4.3  24.3  240   3  2  10.0   5.5 |  -3.4  25.9  175   4  2   9.9   5.4
  6500  -3.6  25.5  245   3  2   9.6   5.3 |  -2.6  27.3  175   4  2   9.7   5.3
  6250  -2.8  27.0  245   3  2  10.6   5.8 |  -1.9  28.6  175   4  2   9.9   5.4
  6000  -2.0  28.4  245   3  2  10.9   6.0 |  -1.2  29.8  175   3  2   9.8   5.4
  5750  -1.2  29.8  245   3  2  10.5   5.8 |  -0.4  31.3  175   3  2   9.7   5.3
  5500  -0.4  31.3  245   3  2  11.9   6.5 |   0.2  32.4  180   3  1   7.9   4.4
  5250   0.6  33.1  250   3  2  14.5   8.0 |   0.7  33.3  180   3  1   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 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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