Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 021347
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0747 MDT Thursday, October 2, 2014

This forecast is for Thursday, October 2, 2014:

If the trigger temperature of 52.1 F/11.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 586 ft/min (3.0 m/s)
   Maximum height of thermals.................. 12561 ft MSL (7722 ft AGL)

Forecast maximum temperature................... 60.0 F/16.0 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11051 ft MSL (6211 ft AGL)
Thermal soaring outlook for Friday 10/03....... Excellent

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

Remarks...

Sunrise/Sunset.................... 07:11:09 / 18:56:38 MDT
Total possible sunshine........... 11 hr 45 min 29 sec (705 min 29 sec)
Altitude of sun at 13:03:25 MDT... 47.13 degrees

Upper air data from rawinsonde observation taken on 10/02/2014 at 0600 MDT

Freezing level.................. 8495 ft MSL (3656 ft AGL)
Convective condensation level... 10933 ft MSL (6094 ft AGL)
Lifted condensation level....... 12243 ft MSL (7404 ft AGL)
Lifted index.................... +6.9
K index......................... -29.7

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  -62.4 -80.3   295   44   23   5.4   2.9   95.1 203.1    45.5      M    M
 45000  -55.8 -68.4   305   61   32  -5.2  -2.9   81.8 179.3    40.6      M    M
 40000  -53.8 -64.8   320   56   29  -5.3  -2.9   61.7 143.1    30.2      M    M
 38000  -53.4 -64.1   330   82   42  -0.7  -0.4   53.5 128.3    25.5      M    M
 36000  -52.5 -62.5   335   86   44   6.2   3.4   45.0 112.9    20.4      M    M
 34000  -48.5 -55.3   345   71   37   7.4   4.1   42.5 108.5    19.2      M    M
 32000  -43.4 -46.1   350   74   38   8.7   4.8   41.2 106.2    18.8      M    M
 30000  -38.4 -37.1   345   75   39   8.0   4.4   40.3 104.5    18.5      M    M
 29000  -36.0 -32.8   345   72   37   8.0   4.4   39.5 103.1    18.1      M    M
 28000  -33.6 -28.5   350   69   35   8.0   4.4   38.8 101.8    17.8      M    M
 27000  -31.2 -24.2   350   66   34   8.1   4.4   38.2 100.8    17.6      M    M
 26000  -28.9 -20.0   345   62   32   7.5   4.1   37.4  99.3    17.1      M    M
 25000  -26.8 -16.2   340   59   30   4.4   2.4   36.4  97.5    16.6      M    M
 24000  -25.9 -14.6   340   63   32  -0.1  -0.0   33.9  93.0    14.7      M    M
 23000  -24.1 -11.4   340   64   33   7.9   4.3   32.5  90.5    13.8      M    M
 22000  -21.7  -7.1   340   58   30   7.8   4.3   31.7  89.1    13.3      M    M
 21000  -19.4  -2.9   345   51   26   7.9   4.3   31.0  87.9    12.9      M    M
 20000  -17.0   1.4   345   44   23   7.9   4.3   30.5  86.8    12.6      M    M
 19500  -15.8   3.6   340   43   22   7.9   4.3   30.1  86.2    12.3      M    M
 19000  -14.1   6.6   335   44   23   4.1   2.3   29.5  85.1    11.9      M    M
 18500  -13.6   7.5   335   44   23   4.8   2.6   28.3  83.0    11.0      M    M
 18000  -12.9   8.8   335   44   22   4.4   2.4   27.4  81.2    10.2      M    M
 17500  -12.3   9.9   335   43   22   4.4   2.4   26.4  79.6     9.5      M    M
 17000  -11.6  11.1   340   43   22   4.6   2.5   25.5  78.0     8.7      M    M
 16500  -11.1  12.0   340   43   22   0.6   0.4   24.5  76.1     7.8      M    M
 16000  -11.3  11.7   340   43   22   3.0   1.7   22.7  72.8     6.3      M    M
 15500  -10.0  14.0   340   42   22   9.0   4.9   22.4  72.3     6.1      M    M
 15000   -8.7  16.3   345   41   21   9.1   5.0   22.3  72.1     6.0      M    M
 14500   -7.4  18.7   345   41   21   4.9   2.7   22.0  71.7     5.8      M    M
 14000   -6.9  19.6   345   39   20  -4.7  -2.6   21.0  69.8     4.9      M    M
 13500   -8.3  17.1   345   33   17  -4.0  -2.2   18.0  64.4     2.1      M    M
 13000   -8.1  17.4   350   27   14   7.1   3.9   16.6  61.9     0.8      M    M
 12500   -7.7  18.1   355   21   11  -1.4  -0.8   15.6  60.1    -0.2    583  3.0
 12000   -8.7  16.3   360   15    8   0.8   0.4   13.0  55.4    -2.7    598  3.0
 11500   -7.4  18.7   360   16    8   8.5   4.7   12.9  55.1    -2.9    544  2.8
 11000   -6.0  21.2   355   18    9   9.0   4.9   12.7  54.9    -3.0    488  2.5
 10500   -4.6  23.7   355   19   10   8.8   4.8   12.6  54.8    -3.1    433  2.2
 10250   -4.0  24.8   355   20   10  10.0   5.5   12.6  54.7    -3.2    405  2.1
 10000   -3.2  26.2   355   20   10   8.8   4.9   12.6  54.8    -3.2    375  1.9
  9750   -2.7  27.1   360   21   11   6.7   3.7   12.4  54.4    -3.4    352  1.8
  9500   -2.2  28.0   360   21   11   7.3   4.0   12.2  54.0    -3.6    329  1.7
  9250   -1.7  28.9   005   22   11   7.2   3.9   12.0  53.7    -3.8    306  1.6
  9000   -1.1  30.0   005   22   11   7.2   4.0   11.9  53.3    -4.0    283  1.4
  8750   -0.6  30.9   005   20   10   7.2   4.0   11.7  53.0    -4.2    260  1.3
  8500   -0.1  31.8   010   17    9   7.2   4.0   11.5  52.6    -4.5    237  1.2
  8250    0.4  32.7   010   15    8   7.3   4.0   11.3  52.3    -4.7    214  1.1
  8000    1.0  33.8   015   12    6   7.1   3.9   11.1  51.9    -4.9    191  1.0
  7750    1.5  34.7   015   10    5   8.0   4.4   10.9  51.6    -5.1    168  0.9
  7500    2.1  35.8   020    8    4   9.2   5.0   10.8  51.4    -5.2    141  0.7
  7250    2.8  37.0   025    6    3   9.2   5.1   10.8  51.4    -5.3    113  0.6
  7000    3.5  38.3   035    4    2   9.2   5.1   10.7  51.3    -5.3     85  0.4
  6750    4.2  39.6   040    4    2   9.2   5.1   10.7  51.2    -5.4     57  0.3
  6500    4.9  40.8   040    3    2   9.2   5.1   10.6  51.1    -5.5     29  0.1
  6250    5.5  41.9   040    3    1   9.2   5.1   10.6  51.1    -5.5      1  0.0
  6000    6.2  43.2   040    2    1   9.3   5.1   10.6  51.0    -5.6      M    M
  5750    6.9  44.4   020    2    1   7.5   4.1   10.5  50.9    -5.7      M    M
  5500    7.3  45.1   335    1    1   5.8   3.2   10.2  50.4    -6.0      M    M
  5250    7.4  45.3   305    2    1  -4.6  -2.5    9.7  49.4    -6.7      M    M
  5000    6.2  43.2   290    3    2 -22.8 -12.5    7.9  46.2    -8.6      M    M

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

           10/02/2014 at 0900 MDT          |       10/02/2014 at 1200 MDT
                                           |
K index... -14.2  LI... +8.1               | K index... -5.8  LI... +8.8
CAPE... +7.3  CIN... -0.3                  | 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 -61.4 -78.5  300  42 22   2.1   1.2 | -60.8 -77.4  305  48 25   1.7   1.0
 45000 -58.4 -73.1  310  59 30   0.9   0.5 | -58.4 -73.1  305  65 34   1.1   0.6
 40000 -57.1 -70.8  320  82 42   0.9   0.5 | -56.8 -70.2  315  80 41   1.0   0.5
 38000 -54.9 -66.8  325  80 41   4.5   2.5 | -54.9 -66.8  315  79 41   3.6   2.0
 36000 -51.8 -61.2  325  75 39   4.5   2.5 | -52.4 -62.3  320  76 39   3.6   2.0
 34000 -48.0 -54.4  330  72 37   8.2   4.5 | -48.7 -55.7  320  73 38   8.4   4.6
 32000 -43.1 -45.6  330  72 37   8.2   4.5 | -43.6 -46.5  325  71 37   8.4   4.6
 30000 -38.1 -36.6  335  69 35   8.5   4.7 | -38.5 -37.3  325  66 34   8.7   4.8
 29000 -35.5 -31.9  335  66 34   8.5   4.7 | -35.9 -32.6  325  63 32   8.7   4.8
 28000 -33.0 -27.4  340  64 33   8.5   4.7 | -33.2 -27.8  320  59 31   8.7   4.8
 27000 -30.5 -22.9  340  61 31   7.5   4.1 | -30.7 -23.3  320  57 29   8.2   4.5
 26000 -28.3 -18.9  340  58 30   7.5   4.1 | -28.3 -18.9  320  55 28   8.2   4.5
 25000 -26.1 -15.0  340  55 28   7.5   4.1 | -25.8 -14.4  320  53 27   8.2   4.5
 24000 -23.8 -10.8  340  52 27   7.3   4.0 | -23.3  -9.9  325  51 26   8.1   4.5
 23000 -21.6  -6.9  340  49 25   7.3   4.0 | -20.9  -5.6  325  49 25   8.2   4.5
 22000 -19.5  -3.1  340  46 24   7.3   4.0 | -18.5  -1.3  330  48 24   8.1   4.5
 21000 -17.4   0.7  340  44 23   5.7   3.1 | -16.3   2.7  330  45 23   6.4   3.5
 20000 -15.3   4.5  335  42 22   5.8   3.2 | -13.9   7.0  330  42 22   6.5   3.5
 19500 -14.4   6.1  335  41 21   5.8   3.2 | -12.9   8.8  325  41 21   6.4   3.5
 19000 -13.6   7.5  335  41 21   5.7   3.1 | -12.0  10.4  325  39 20   5.7   3.1
 18500 -12.7   9.1  335  40 21   5.6   3.1 | -11.2  11.8  325  38 20   5.2   2.8
 18000 -11.9  10.6  335  40 20   5.6   3.1 | -10.4  13.3  325  38 19   5.1   2.8
 17500 -11.0  12.2  340  39 20   5.6   3.1 |  -9.6  14.7  325  37 19   5.7   3.2
 17000 -10.2  13.6  340  38 20   5.6   3.1 |  -8.8  16.2  325  36 18   5.7   3.1
 16500  -9.3  15.3  340  37 19   5.6   3.1 |  -7.9  17.8  325  35 18   5.9   3.2
 16000  -8.5  16.7  345  36 18   5.6   3.1 |  -7.0  19.4  325  33 17   5.9   3.2
 15500  -7.6  18.3  345  34 18   5.5   3.0 |  -6.1  21.0  325  31 16   5.7   3.1
 15000  -6.8  19.8  345  33 17   5.2   2.9 |  -5.3  22.5  330  29 15   5.3   2.9
 14500  -6.0  21.2  350  31 16   5.6   3.0 |  -4.5  23.9  330  27 14   5.3   2.9
 14000  -5.5  22.1  350  29 15   1.3   0.7 |  -3.7  25.3  330  25 13   4.8   2.6
 13500  -5.3  22.5  350  26 13   2.2   1.2 |  -3.0  26.6  330  23 12   5.3   2.9
 13000  -5.3  22.5  350  22 12  -2.0  -1.1 |  -2.4  27.7  335  21 11   1.3   0.7
 12500  -5.7  21.7  350  18  9  -2.1  -1.1 |  -2.2  28.0  335  18  9   1.9   1.0
 12000  -5.7  21.7  350  14  7   3.0   1.6 |  -2.1  28.2  335  16  8  -0.4  -0.2
 11500  -5.3  22.5  355  11  5   3.1   1.7 |  -2.2  28.0  335  13  7  -0.2  -0.1
 11000  -4.8  23.4  355   8  4   5.2   2.9 |  -2.3  27.9  335   9  5   0.7   0.4
 10500  -4.1  24.6  360   6  3   5.0   2.8 |  -2.2  28.0  335   6  3   0.4   0.2
 10250  -3.8  25.2  005   6  3   6.6   3.6 |  -2.2  28.0  340   5  2   2.9   1.6
 10000  -3.2  26.2  010   5  3   8.5   4.6 |  -1.9  28.6  340   4  2   6.3   3.4
  9750  -2.6  27.3  015   5  3   8.4   4.6 |  -1.4  29.5  345   3  1   6.4   3.5
  9500  -2.0  28.4  025   5  3   8.5   4.6 |  -1.0  30.2  350   2  1   6.5   3.6
  9250  -1.4  29.5  030   6  3   8.0   4.4 |  -0.5  31.1  005   1  1   6.6   3.6
  9000  -0.8  30.6  030   6  3   7.8   4.3 |  -0.0  32.0  030   1  0   6.9   3.8
  8750  -0.2  31.6  035   6  3   8.1   4.4 |   0.5  32.9  075   1  0   7.8   4.3
  8500   0.4  32.7  035   7  4   7.9   4.3 |   1.1  34.0  115   1  1   7.7   4.2
  8250   1.0  33.8  035   8  4   7.5   4.1 |   1.6  34.9  135   1  1   6.9   3.8
  8000   1.5  34.7  040   8  4   7.2   4.0 |   2.1  35.8  150   2  1   6.7   3.7
  7750   2.1  35.8  040   8  4   8.0   4.4 |   2.6  36.7  160   2  1   7.8   4.3
  7500   2.6  36.7  045   8  4   6.3   3.4 |   3.2  37.8  170   2  1   8.5   4.7
  7250   3.0  37.4  050   7  4   4.3   2.4 |   3.8  38.8  175   2  1   8.4   4.6
  7000   3.4  38.1  060   6  3   4.9   2.7 |   4.4  39.9  180   2  1   8.0   4.4
  6750   3.7  38.7  070   6  3   4.6   2.5 |   5.0  41.0  185   3  1  10.0   5.5
  6500   4.0  39.2  085   4  2   3.7   2.0 |   5.8  42.4  190   3  1  11.3   6.2
  6250   4.2  39.6  105   4  2   2.8   1.5 |   6.6  43.9  195   3  1  10.4   5.7
  6000   4.5  40.1  130   4  2   4.4   2.4 |   7.4  45.3  195   3  2  10.3   5.7
  5750   4.9  40.8  145   4  2   9.9   5.4 |   8.2  46.8  200   3  2  15.5   8.5
  5500   5.8  42.4  145   4  2  14.4   7.9 |   9.8  49.6  200   3  2  25.2  13.8
  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

           10/02/2014 at 1500 MDT          |       10/02/2014 at 1800 MDT
                                           |
K index... -7.3  LI... +8.9                | K index... +10.5  LI... +8.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.2
                                           |
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 -61.7 -79.1  300  53 27   0.7   0.4 | -60.4 -76.7  295  55 28   2.4   1.3
 45000 -60.3 -76.5  300  66 34   2.1   1.1 | -57.6 -71.7  290  66 34  -1.8  -1.0
 40000 -57.2 -71.0  315  85 44   2.0   1.1 | -60.4 -76.7  320  80 41  -2.7  -1.5
 38000 -55.2 -67.4  320  82 42   3.7   2.0 | -56.6 -69.9  325  77 40   6.8   3.7
 36000 -52.8 -63.0  330  78 40   3.6   2.0 | -52.6 -62.7  330  72 37   6.8   3.7
 34000 -48.7 -55.7  330  78 40   9.0   5.0 | -47.6 -53.7  330  72 37   9.2   5.1
 32000 -43.3 -45.9  335  78 40   9.0   4.9 | -42.0 -43.6  330  74 38   9.2   5.1
 30000 -37.9 -36.2  335  76 39   8.8   4.8 | -36.7 -34.1  330  72 37   8.5   4.7
 29000 -35.3 -31.5  335  75 39   8.8   4.9 | -34.2 -29.6  330  70 36   8.5   4.7
 28000 -32.6 -26.7  335  74 38   8.9   4.9 | -31.6 -24.9  330  67 35   8.6   4.7
 27000 -30.1 -22.2  335  68 35   7.9   4.3 | -29.4 -20.9  330  64 33   7.0   3.8
 26000 -27.8 -18.0  330  59 30   7.9   4.3 | -27.3 -17.1  330  61 31   7.0   3.8
 25000 -25.4 -13.7  325  50 26   7.9   4.3 | -25.2 -13.4  335  58 30   7.0   3.9
 24000 -23.0  -9.4  320  44 23   8.3   4.5 | -23.0  -9.4  330  54 28   8.4   4.6
 23000 -20.5  -4.9  320  43 22   8.3   4.5 | -20.5  -4.9  325  49 25   8.3   4.6
 22000 -18.1  -0.6  320  43 22   8.3   4.5 | -18.0  -0.4  315  45 23   8.3   4.6
 21000 -15.8   3.6  315  42 22   7.0   3.8 | -15.0   5.0  315  44 23   7.5   4.1
 20000 -13.2   8.2  315  41 21   7.0   3.8 | -12.8   9.0  315  45 23   7.5   4.1
 19500 -12.2  10.0  315  41 21   7.0   3.8 | -11.7  10.9  315  46 24   7.5   4.1
 19000 -11.2  11.8  315  41 21   5.6   3.0 | -10.6  12.9  320  46 24   6.8   3.7
 18500 -10.5  13.1  315  40 20   4.9   2.7 |  -9.6  14.7  320  45 23   6.6   3.6
 18000  -9.8  14.4  315  39 20   4.9   2.7 |  -8.7  16.3  320  45 23   6.3   3.5
 17500  -9.1  15.6  315  38 20   5.5   3.0 |  -8.0  17.6  320  43 22   3.5   1.9
 17000  -8.3  17.1  315  37 19   5.5   3.0 |  -7.5  18.5  320  42 21   3.7   2.0
 16500  -7.5  18.5  315  35 18   4.7   2.6 |  -7.0  19.4  320  40 21   3.6   2.0
 16000  -6.7  19.9  320  34 17   4.6   2.5 |  -6.5  20.3  325  37 19   3.6   2.0
 15500  -6.0  21.2  320  32 16   4.7   2.6 |  -6.0  21.2  325  35 18   3.9   2.1
 15000  -5.3  22.5  320  29 15   4.8   2.6 |  -5.3  22.5  325  32 16   4.2   2.3
 14500  -4.5  23.9  315  27 14   4.9   2.7 |  -4.7  23.5  325  29 15   4.4   2.4
 14000  -3.8  25.2  315  25 13   5.3   2.9 |  -3.9  25.0  325  26 14   5.3   2.9
 13500  -2.9  26.8  315  23 12   5.3   2.9 |  -3.1  26.4  320  24 12   5.3   2.9
 13000  -2.3  27.9  310  21 11   3.6   2.0 |  -2.2  28.0  320  23 12   5.8   3.2
 12500  -1.7  28.9  310  19 10   3.9   2.1 |  -1.4  29.5  320  22 11   5.8   3.2
 12000  -1.2  29.8  305  18  9   3.0   1.6 |  -0.6  30.9  320  20 11   5.3   2.9
 11500  -0.7  30.7  300  16  8   3.0   1.6 |   0.2  32.4  320  19 10   5.4   3.0
 11000  -0.2  31.6  300  14  7   4.3   2.3 |   0.9  33.6  315  17  9   4.9   2.7
 10500   0.4  32.7  295  13  7   4.3   2.3 |   1.6  34.9  310  14  7   5.2   2.8
 10250   0.7  33.3  290  12  6   3.9   2.1 |   1.9  35.4  305  12  6   5.0   2.8
 10000   1.0  33.8  290  11  6   5.1   2.8 |   2.3  36.1  300  11  6   6.5   3.6
  9750   1.4  34.5  290  10  5   6.4   3.5 |   2.8  37.0  295  11  5   7.8   4.3
  9500   1.8  35.2  285   9  5   6.1   3.3 |   3.4  38.1  290  10  5   7.4   4.1
  9250   2.3  36.1  285   9  4   6.2   3.4 |   3.9  39.0  285   9  5   7.0   3.9
  9000   2.7  36.9  280   8  4   6.3   3.5 |   4.5  40.1  280   9  5   7.3   4.0
  8750   3.2  37.8  275   7  4   6.9   3.8 |   5.1  41.2  280   9  5   8.5   4.7
  8500   3.7  38.7  265   7  3   6.6   3.6 |   5.7  42.3  275   9  5   7.9   4.3
  8250   4.1  39.4  265   6  3   5.6   3.1 |   6.3  43.3  275   9  5   6.5   3.6
  8000   4.5  40.1  260   5  3   5.7   3.1 |   6.7  44.1  280   9  5   6.2   3.4
  7750   4.9  40.8  260   5  2   6.2   3.4 |   7.2  45.0  280   9  5   5.5   3.0
  7500   5.3  41.5  260   4  2   8.5   4.7 |   7.5  45.5  280   8  4   4.4   2.4
  7250   6.0  42.8  260   4  2  10.0   5.5 |   7.8  46.0  280   7  4   4.1   2.3
  7000   6.7  44.1  260   4  2   9.6   5.3 |   8.1  46.6  280   5  3   3.9   2.1
  6750   7.4  45.3  260   4  2   9.8   5.4 |   8.3  46.9  280   4  2   5.2   2.9
  6500   8.1  46.6  260   4  2  10.2   5.6 |   8.9  48.0  280   3  2   8.5   4.7
  6250   8.9  48.0  260   4  2  10.2   5.6 |   9.5  49.1  280   3  2   9.4   5.1
  6000   9.7  49.5  260   4  2  10.8   5.9 |  10.2  50.4  280   3  2   9.6   5.3
  5750  10.6  51.1  260   4  2  16.6   9.1 |  11.0  51.8  275   3  2  11.6   6.3
  5500  12.1  53.8  265   4  2  24.1  13.2 |  11.9  53.4  280   3  2  13.1   7.2
  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 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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