Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 251313
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0613 MST Sunday, January 25, 2015

This forecast is for Sunday, January 25, 2015:

If the trigger temperature of 54.1 F/12.3 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 202 ft/min (1.0 m/s)
   Maximum height of thermals.................. 7209 ft MSL (2370 ft AGL)

Forecast maximum temperature................... 46.0 F/8.2 C
Time of trigger temperature.................... None
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................. 5957 ft MSL (1118 ft AGL)
Thermal soaring outlook for Monday 01/26....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:26:19 / 17:25:38 MST
Total possible sunshine........... 9 hr 59 min 19 sec (599 min 19 sec)
Altitude of sun at 12:26:22 MST... 32.04 degrees

Upper air data from rawinsonde observation taken on 01/25/2015 at 0500 MST

Freezing level.................. 5464 ft MSL (625 ft AGL)
Additional freezing level....... 8919 ft MSL (4080 ft AGL)
Convective condensation level... 19672 ft MSL (14833 ft AGL)
Lifted condensation level....... 12064 ft MSL (7225 ft AGL)
Lifted index.................... +15.6
K index......................... +3.5

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  -62.9 -81.2   335   43   22   4.0   2.2   95.9 204.6    50.2      M    M
 45000  -53.9 -65.0   330   24   13   6.8   3.7   86.1 187.0    47.8      M    M
 40000  -64.3 -83.7   345   77   39  -1.9  -1.0   46.6 115.9    25.4      M    M
 38000  -61.0 -77.8   350   53   27   7.7   4.2   42.8 109.1    23.5      M    M
 36000  -56.4 -69.5   010   55   28   8.0   4.4   41.1 105.9    23.0      M    M
 34000  -52.5 -62.5   015   72   37   9.6   5.3   37.2  99.0    20.9      M    M
 32000  -47.1 -52.8   360   69   35   8.5   4.7   36.6  97.9    21.0      M    M
 30000  -41.7 -43.1   360   62   32   9.2   5.0   36.0  96.7    21.1      M    M
 29000  -39.0 -38.2   360   61   31   9.2   5.0   35.7  96.2    21.1      M    M
 28000  -36.2 -33.2   360   60   31   8.3   4.5   35.4  95.8    21.2      M    M
 27000  -33.9 -29.0   355   58   30   7.6   4.2   34.5  94.2    20.8      M    M
 26000  -31.7 -25.1   355   57   29   7.4   4.1   33.8  92.8    20.4      M    M
 25000  -29.0 -20.2   355   56   29   9.5   5.2   33.6  92.4    20.5      M    M
 24000  -26.2 -15.2   355   54   28   8.3   4.6   33.3  92.0    20.6      M    M
 23000  -24.4 -11.9   355   52   27   7.7   4.2   32.0  89.6    19.7      M    M
 22000  -21.9  -7.4   350   50   26   8.9   4.9   31.5  88.6    19.5      M    M
 21000  -19.2  -2.6   350   48   25   9.4   5.1   31.2  88.1    19.4      M    M
 20000  -18.0  -0.4   340   44   23   2.6   1.4   29.3  84.7    18.0      M    M
 19500  -17.1   1.2   335   43   22   7.6   4.2   28.5  83.4    17.5      M    M
 19000  -16.1   3.0   330   42   22   6.1   3.4   28.1  82.6    17.2      M    M
 18500  -14.6   5.7   335   41   21   8.4   4.6   27.3  81.1    16.6      M    M
 18000  -13.3   8.1   340   41   21   8.2   4.5   27.0  80.6    16.5      M    M
 17500  -12.1  10.2   340   40   21   8.2   4.5   26.8  80.2    16.4      M    M
 17000  -10.9  12.4   345   40   21   8.2   4.5   26.6  79.8    16.3      M    M
 16500   -9.6  14.7   340   39   20   8.2   4.5   26.3  79.3    16.1      M    M
 16000   -8.4  16.9   340   39   20   8.2   4.5   26.0  78.8    16.0      M    M
 15500   -7.2  19.0   335   37   19   8.3   4.5   25.7  78.3    15.8      M    M
 15000   -6.2  20.8   330   35   18   0.9   0.5   25.2  77.4    15.4      M    M
 14500   -6.7  19.9   335   31   16  -3.4  -1.9   23.1  73.6    13.5      M    M
 14000   -6.4  20.5   345   28   14   7.1   3.9   21.8  71.2    12.4      M    M
 13500   -5.5  22.1   340   25   13   5.9   3.3   21.2  70.1    11.9      M    M
 13000   -4.6  23.7   330   23   12   4.4   2.4   20.6  69.0    11.4      M    M
 12500   -4.5  23.9   340   28   14   1.0   0.5   19.2  66.5    10.1      M    M
 12000   -4.1  24.6   350   33   17   2.4   1.3   18.0  64.4     9.1      M    M
 11500   -3.5  25.7   350   26   13   6.7   3.7   17.1  62.8     8.3      M    M
 11000   -2.5  27.5   350   19   10   6.3   3.4   16.6  61.8     7.8      M    M
 10500   -1.6  29.1   335   14    7   6.1   3.4   16.0  60.8     7.3      M    M
 10250   -1.2  29.8   330   13    7   5.5   3.0   15.7  60.3     7.0      M    M
 10000   -0.9  30.4   330   13    7   2.5   1.4   15.3  59.5     6.6      M    M
  9750   -0.8  30.6   340   12    6   0.9   0.5   14.6  58.3     6.0      M    M
  9500   -0.8  30.6   355   12    6   0.6   0.3   13.9  57.0     5.3      M    M
  9250   -0.7  30.7   010   12    6   3.7   2.0   13.2  55.8     4.7      M    M
  9000   -0.2  31.6   025   13    7   7.2   3.9   13.0  55.4     4.4      M    M
  8750    0.3  32.5   035   12    6   7.0   3.8   12.7  54.9     4.2      M    M
  8500    0.8  33.4   045   11    6   5.3   2.9   12.5  54.5     4.0      M    M
  8250    1.2  34.2   055   10    5   7.0   3.8   12.1  53.8     3.7      M    M
  8000    1.5  34.7   070   10    5  -2.8  -1.6   11.8  53.2     3.3      M    M
  7750    0.8  33.4   075    8    4 -13.9  -7.6   10.2  50.3     1.9      M    M
  7500    0.4  32.7   085    7    4   2.8   1.5    8.8  47.9     0.7      M    M
  7250    0.9  33.6   100    6    3  -0.7  -0.4    8.6  47.4     0.5      M    M
  7000    0.3  32.5   125    5    3  -5.2  -2.9    7.2  45.0    -0.8    208  1.1
  6750    0.5  32.9   120    5    2   5.1   2.8    6.6  44.0    -1.4    196  1.0
  6500    0.7  33.3   110    5    2   3.6   2.0    6.2  43.1    -1.9    180  0.9
  6250    1.0  33.8   100    5    2   3.4   1.9    5.7  42.3    -2.3    165  0.8
  6000    1.3  34.3   090    5    3   5.7   3.1    5.3  41.5    -2.8    149  0.8
  5750    1.5  34.7   105    6    3  -3.2  -1.7    4.8  40.7    -3.3    134  0.7
  5500    0.6  33.1   120    8    4 -19.0 -10.4    3.2  37.7    -4.9    155  0.8
  5250   -0.7  30.7   130   10    5  -9.7  -5.3    1.1  34.0    -7.0    186  0.9
  5000   -0.9  30.4   130    8    4  -0.5  -0.3    0.2  32.4    -7.9    183  0.9

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

           01/25/2015 at 0800 MST          |       01/25/2015 at 1100 MST
                                           |
K index... +3.9  LI... +8.5                | K index... +0.7  LI... +9.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -60.7 -77.3  350  33 17   3.4   1.9 | -62.1 -79.8  350  33 17   3.2   1.7
 45000 -56.2 -69.2  355  35 18  -6.0  -3.3 | -58.1 -72.6  355  41 21  -4.0  -2.2
 40000 -64.1 -83.4  360  56 29  -5.0  -2.7 | -63.6 -82.5  005  57 29  -3.4  -1.8
 38000 -61.5 -78.7  005  59 30   8.4   4.6 | -61.0 -77.8  010  59 30   7.5   4.1
 36000 -56.5 -69.7  015  60 31   8.4   4.6 | -55.9 -68.6  020  60 31   7.5   4.1
 34000 -50.8 -59.4  020  61 31   8.6   4.7 | -51.1 -60.0  020  56 29   8.7   4.8
 32000 -45.6 -50.1  020  60 31   8.6   4.7 | -45.9 -50.6  015  46 24   8.7   4.8
 30000 -40.5 -40.9  020  59 31   8.4   4.6 | -40.6 -41.1  015  42 22   8.8   4.8
 29000 -38.0 -36.4  020  59 30   8.4   4.6 | -38.0 -36.4  015  43 22   8.8   4.8
 28000 -35.5 -31.9  020  59 30   8.4   4.6 | -35.4 -31.7  015  44 22   8.8   4.8
 27000 -33.0 -27.4  020  58 30   7.9   4.3 | -32.7 -26.9  015  44 22   8.9   4.9
 26000 -30.7 -23.3  020  57 29   7.9   4.3 | -30.0 -22.0  015  43 22   8.9   4.9
 25000 -28.3 -18.9  020  55 29   7.9   4.3 | -27.3 -17.1  015  43 22   8.9   4.9
 24000 -25.9 -14.6  020  53 27   9.0   4.9 | -24.7 -12.5  015  41 21   8.3   4.6
 23000 -23.3  -9.9  015  50 26   8.9   4.9 | -22.2  -8.0  015  38 20   8.3   4.6
 22000 -20.6  -5.1  010  47 24   8.9   4.9 | -19.8  -3.6  015  36 18   8.4   4.6
 21000 -18.0  -0.4  005  43 22   8.8   4.8 | -17.2   1.0  010  31 16   9.0   5.0
 20000 -15.3   4.5  360  39 20   8.8   4.8 | -13.8   7.2  350  25 13   9.1   5.0
 19500 -14.0   6.8  360  38 19   8.8   4.9 | -12.4   9.7  345  24 12   9.1   5.0
 19000 -12.1  10.2  355  35 18   8.1   4.4 | -11.1  12.0  335  23 12   7.7   4.2
 18500 -10.9  12.4  350  35 18   7.6   4.2 | -10.0  14.0  335  25 13   7.2   4.0
 18000  -9.8  14.4  350  36 18   7.7   4.2 |  -9.0  15.8  330  27 14   7.0   3.9
 17500  -8.9  16.0  345  36 19   4.6   2.5 |  -8.1  17.4  335  29 15   5.2   2.9
 17000  -8.2  17.2  345  36 18   4.9   2.7 |  -7.3  18.9  335  31 16   5.4   3.0
 16500  -7.5  18.5  340  36 18   4.5   2.5 |  -6.6  20.1  340  33 17   4.3   2.4
 16000  -6.9  19.6  340  35 18   4.3   2.3 |  -6.0  21.2  345  35 18   4.1   2.2
 15500  -6.2  20.8  340  35 18   3.7   2.0 |  -5.4  22.3  350  37 19   3.6   2.0
 15000  -5.9  21.4  335  34 18   2.4   1.3 |  -4.9  23.2  355  37 19   3.0   1.7
 14500  -5.5  22.1  335  34 17   2.4   1.3 |  -4.5  23.9  355  36 19   2.9   1.6
 14000  -5.2  22.6  335  33 17   2.5   1.4 |  -4.2  24.4  355  36 18   1.9   1.0
 13500  -4.8  23.4  340  32 16   2.6   1.4 |  -3.9  25.0  350  35 18   2.0   1.1
 13000  -4.5  23.9  340  31 16   2.0   1.1 |  -3.8  25.2  350  34 17   0.4   0.2
 12500  -4.3  24.3  345  29 15   2.0   1.1 |  -3.8  25.2  350  31 16   0.6   0.3
 12000  -4.0  24.8  350  28 14   2.7   1.5 |  -3.7  25.3  350  28 14   0.7   0.4
 11500  -3.6  25.5  355  27 14   2.7   1.5 |  -3.7  25.3  355  24 12   0.5   0.3
 11000  -3.2  26.2  360  25 13   2.9   1.6 |  -3.4  25.9  360  21 11   4.6   2.5
 10500  -2.8  27.0  010  23 12   2.9   1.6 |  -2.8  27.0  010  20 10   4.3   2.4
 10250  -2.6  27.3  015  23 12   3.3   1.8 |  -2.5  27.5  015  19 10   3.2   1.7
 10000  -2.3  27.9  015  22 11   5.5   3.0 |  -2.3  27.9  015  18  9   4.7   2.6
  9750  -1.8  28.8  015  21 11   7.8   4.3 |  -1.8  28.8  015  18  9   8.7   4.8
  9500  -1.2  29.8  015  20 10   7.9   4.3 |  -1.1  30.0  020  18  9   8.3   4.6
  9250  -0.7  30.7  015  19 10   4.3   2.4 |  -0.6  30.9  020  18  9   5.7   3.1
  9000  -0.5  31.1  015  18  9   2.1   1.2 |  -0.2  31.6  020  18  9   4.6   2.5
  8750  -0.3  31.5  020  17  9   4.0   2.2 |   0.2  32.4  025  18  9   6.7   3.7
  8500   0.0  32.0  020  16  8   3.5   1.9 |   0.7  33.3  025  18  9   4.8   2.6
  8250   0.2  32.4  025  15  8   1.8   1.0 |   0.9  33.6  030  17  9   1.6   0.9
  8000   0.4  32.7  030  13  7   1.4   0.8 |   1.0  33.8  030  15  8   1.7   1.0
  7750   0.5  32.9  035  12  6   2.1   1.2 |   1.2  34.2  035  14  7   2.4   1.3
  7500   0.7  33.3  045  10  5   3.4   1.8 |   1.4  34.5  045  12  6   2.5   1.4
  7250   1.0  33.8  055   8  4   3.7   2.0 |   1.6  34.9  050  10  5   1.7   0.9
  7000   1.3  34.3  065   7  3   3.5   1.9 |   1.7  35.1  060   8  4   2.0   1.1
  6750   1.6  34.9  080   5  3   3.9   2.1 |   1.9  35.4  080   7  3   1.6   0.9
  6500   1.9  35.4  095   5  2   2.4   1.3 |   2.0  35.6  085   5  2   2.5   1.4
  6250   2.0  35.6  110   4  2   1.8   1.0 |   2.3  36.1  100   3  2   2.4   1.3
  6000   2.1  35.8  125   4  2   0.2   0.1 |   2.5  36.5  135   3  1   5.4   3.0
  5750   1.8  35.2  130   4  2 -12.2  -6.7 |   3.2  37.8  145   3  1  12.2   6.7
  5500   0.2  32.4  110   4  2 -26.5 -14.5 |   4.1  39.4  145   2  1  13.8   7.6
  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

           01/25/2015 at 1400 MST          |       01/25/2015 at 1700 MST
                                           |
K index... -0.9  LI... +10.5               | K index... -1.5  LI... +10.9
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 -63.0 -81.4  345  30 16   2.5   1.4 | -63.0 -81.4  340  27 14   2.3   1.2
 45000 -59.8 -75.6  355  40 20  -2.7  -1.5 | -60.2 -76.4  345  33 17  -2.5  -1.4
 40000 -63.6 -82.5  005  40 21  -2.2  -1.2 | -63.8 -82.8  360  39 20  -2.3  -1.3
 38000 -60.1 -76.2  005  41 21   7.3   4.0 | -60.6 -77.1  005  40 21   7.8   4.3
 36000 -55.7 -68.3  010  42 22   7.3   4.0 | -55.3 -67.5  005  41 21   7.8   4.3
 34000 -50.8 -59.4  010  41 21   8.8   4.8 | -50.2 -58.4  005  40 21   9.1   5.0
 32000 -45.6 -50.1  360  41 21   8.8   4.8 | -44.7 -48.5  005  38 20   9.1   5.0
 30000 -40.2 -40.4  360  40 21   9.2   5.0 | -39.4 -38.9  005  35 18   8.8   4.8
 29000 -37.4 -35.3  360  40 20   9.2   5.1 | -36.8 -34.2  005  33 17   8.8   4.8
 28000 -34.7 -30.5  360  39 20   9.2   5.1 | -34.1 -29.4  005  30 16   8.8   4.8
 27000 -32.0 -25.6  360  39 20   8.7   4.8 | -31.5 -24.7  360  29 15   8.4   4.6
 26000 -29.4 -20.9  355  38 19   8.7   4.8 | -29.0 -20.2  350  29 15   8.4   4.6
 25000 -26.8 -16.2  355  37 19   8.7   4.8 | -26.5 -15.7  340  30 16   8.4   4.6
 24000 -24.1 -11.4  350  34 18   9.0   4.9 | -23.9 -11.0  335  30 16   9.0   4.9
 23000 -21.4  -6.5  350  30 15   9.0   4.9 | -21.2  -6.2  330  29 15   9.0   4.9
 22000 -18.8  -1.8  345  26 13   9.0   4.9 | -18.5  -1.3  325  27 14   9.0   4.9
 21000 -15.4   4.3  335  23 12   8.8   4.8 | -15.3   4.5  320  27 14   8.5   4.7
 20000 -12.8   9.0  325  22 12   8.8   4.8 | -12.7   9.1  315  29 15   8.5   4.7
 19500 -11.5  11.3  320  22 11   8.9   4.9 | -11.4  11.5  310  29 15   8.5   4.7
 19000 -10.3  13.5  320  23 12   7.4   4.1 | -10.2  13.6  310  30 15   8.2   4.5
 18500  -9.2  15.4  315  25 13   7.0   3.9 |  -9.0  15.8  310  29 15   8.1   4.5
 18000  -8.2  17.2  315  27 14   6.7   3.7 |  -7.7  18.1  310  29 15   7.6   4.1
 17500  -7.4  18.7  315  27 14   4.5   2.5 |  -7.0  19.4  315  28 15   4.2   2.3
 17000  -6.7  19.9  320  27 14   4.7   2.6 |  -6.3  20.7  325  28 14   4.4   2.4
 16500  -6.1  21.0  330  26 14   3.4   1.9 |  -5.7  21.7  330  27 14   4.8   2.6
 16000  -5.6  21.9  335  26 13   3.3   1.8 |  -5.0  23.0  335  26 13   4.8   2.6
 15500  -5.2  22.6  345  25 13   3.8   2.1 |  -4.2  24.4  340  25 13   4.9   2.7
 15000  -4.5  23.9  350  26 13   4.3   2.3 |  -3.5  25.7  345  24 12   4.9   2.7
 14500  -3.9  25.0  355  27 14   4.4   2.4 |  -2.8  27.0  350  23 12   4.6   2.5
 14000  -3.2  26.2  355  28 14   4.6   2.5 |  -2.2  28.0  355  22 11   2.9   1.6
 13500  -2.5  27.5  360  29 15   4.6   2.5 |  -1.8  28.8  360  22 11   3.0   1.6
 13000  -2.0  28.4  360  29 15   2.4   1.3 |  -1.5  29.3  360  22 11   1.4   0.8
 12500  -1.7  28.9  360  29 15   2.8   1.5 |  -1.3  29.7  360  22 11   1.5   0.8
 12000  -1.4  29.5  005  28 14   0.9   0.5 |  -1.0  30.2  005  22 11   2.5   1.4
 11500  -1.3  29.7  005  27 14   1.4   0.8 |  -0.7  30.7  005  22 11   2.5   1.4
 11000  -1.4  29.5  005  25 13  -2.0  -1.1 |  -0.4  31.3  010  21 11   1.9   1.0
 10500  -1.8  28.8  010  21 11  -1.6  -0.9 |  -0.2  31.6  010  19 10   2.1   1.1
 10250  -1.9  28.6  015  19 10   1.1   0.6 |  -0.1  31.8  010  19 10   1.8   1.0
 10000  -1.7  28.9  015  18  9   3.3   1.8 |   0.0  32.0  010  18  9   1.6   0.9
  9750  -1.5  29.3  020  16  8   3.1   1.7 |   0.1  32.2  010  16  8   1.9   1.1
  9500  -1.3  29.7  025  14  7   3.6   2.0 |   0.2  32.4  015  15  8   1.9   1.0
  9250  -1.0  30.2  030  13  7   4.4   2.4 |   0.3  32.5  015  13  7   1.6   0.9
  9000  -0.6  30.9  030  13  7   4.8   2.6 |   0.4  32.7  020  12  6   1.5   0.8
  8750  -0.3  31.5  030  14  7   5.5   3.0 |   0.5  32.9  020  12  6   1.5   0.8
  8500   0.1  32.2  035  15  7   5.0   2.7 |   0.6  33.1  030  11  6   2.0   1.1
  8250   0.4  32.7  035  14  7   3.8   2.1 |   0.8  33.4  035  10  5   2.9   1.6
  8000   0.7  33.3  040  12  6   3.7   2.0 |   1.0  33.8  040  10  5   2.6   1.5
  7750   1.0  33.8  045  11  6   4.6   2.5 |   1.2  34.2  050   9  5   3.9   2.1
  7500   1.4  34.5  050   9  5   4.3   2.4 |   1.6  34.9  055   9  4   5.7   3.2
  7250   1.6  34.9  050   7  4   3.7   2.0 |   2.0  35.6  055   8  4   5.9   3.3
  7000   1.9  35.4  050   5  3   2.6   1.4 |   2.4  36.3  055   7  3   5.9   3.2
  6750   2.2  36.0  050   3  2   7.7   4.2 |   2.9  37.2  055   6  3   6.0   3.3
  6500   3.0  37.4  050   3  2  11.2   6.1 |   3.3  37.9  055   5  2   6.2   3.4
  6250   3.7  38.7  050   3  1   8.3   4.6 |   3.8  38.8  055   3  2   5.7   3.1
  6000   4.4  39.9  050   2  1   9.5   5.2 |   4.2  39.6  060   2  1   7.4   4.0
  5750   5.2  41.4  050   2  1  12.4   6.8 |   4.8  40.6  050   1  1   6.9   3.8
  5500   6.2  43.2  045   2  1  16.3   8.9 |   5.1  41.2  055   1  0   1.1   0.6
  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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