Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 030112
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1912 MDT Thursday, July 2, 2015

This forecast is for Friday, July 3, 2015:

If the trigger temperature of 77.3 F/25.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 975 ft/min (5.0 m/s)
   Maximum height of thermals.................. 14627 ft MSL (9320 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10770 ft MSL (5463 ft AGL)
Thermal soaring outlook for Saturday 07/04..... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change.
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 40823 ft MSL (35516 ft AGL)
Wave soaring outlook for Saturday 07/04........ Poor

Remarks...

Sunrise/Sunset.................... 05:36:12 / 20:31:13 MDT
Total possible sunshine........... 14 hr 55 min 1 sec (895 min 1 sec)
Altitude of sun at 13:03:44 MDT... 73.14 degrees

Upper air data from numerical model forecast valid on 07/03/2015 at 0600 MDT

Freezing level.................. 15486 ft MSL (10179 ft AGL)
Convective condensation level... 13373 ft MSL (8066 ft AGL)
Lifted condensation level....... 13640 ft MSL (8333 ft AGL)
Lifted index.................... -3.5
K index......................... +27.9

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -65.3 -85.5   320   34   17   0.4   0.2      M     M       M      M    M
 45000  -62.2 -80.0   315   54   28   5.7   3.1      M     M       M      M    M
 40000  -53.2 -63.8   315   65   34   8.1   4.4      M     M       M      M    M
 38000  -48.3 -54.9   315   61   31   8.1   4.5      M     M       M      M    M
 36000  -42.8 -45.0   320   57   29   8.0   4.4      M     M       M      M    M
 34000  -38.1 -36.6   320   52   27   7.9   4.3      M     M       M      M    M
 32000  -33.3 -27.9   320   47   24   8.2   4.5      M     M       M      M    M
 30000  -28.4 -19.1   325   44   23   8.2   4.5   48.0 118.3    13.7      M    M
 29000  -25.9 -14.6   325   43   22   8.2   4.5   47.4 117.3    13.4      M    M
 28000  -23.5 -10.3   325   42   22   6.6   3.6   46.8 116.3    13.1      M    M
 27000  -21.7  -7.1   325   40   21   6.2   3.4   45.3 113.6    12.1      M    M
 26000  -19.8  -3.6   330   38   19   6.2   3.4   44.0 111.2    11.2      M    M
 25000  -18.0  -0.4   330   36   18   6.2   3.4   42.8 109.0    10.3      M    M
 24000  -16.1   3.0   330   32   17   6.4   3.5   41.4 106.6     9.4      M    M
 23000  -14.1   6.6   325   28   15   6.4   3.5   40.2 104.4     8.4      M    M
 22000  -12.2  10.0   325   25   13   6.3   3.5   39.1 102.4     7.6      M    M
 21000  -10.5  13.1   325   23   12   5.8   3.2   37.6  99.7     6.4      M    M
 20000   -8.7  16.3   325   22   11   5.8   3.2   36.2  97.2     5.3      M    M
 19500   -7.9  17.8   320   21   11   5.8   3.2   35.6  96.1     4.7      M    M
 19000   -7.0  19.4   320   21   11   6.6   3.6   35.0  95.0     4.2      M    M
 18500   -5.6  21.9   320   21   11   6.7   3.7   34.2  93.5     3.5      M    M
 18000   -4.6  23.7   320   21   11   6.4   3.5   33.6  92.5     3.0      M    M
 17500   -3.8  25.2   320   20   10   6.5   3.5   33.0  91.5     2.4      M    M
 17000   -2.9  26.8   320   20   10   6.8   3.7   32.5  90.5     1.8      M    M
 16500   -1.9  28.6   325   19   10   7.3   4.0   32.0  89.7     1.3      M    M
 16000   -0.9  30.4   325   18    9   7.4   4.1   31.6  89.0     0.8      M    M
 15500    0.2  32.4   330   16    8   8.4   4.6   31.3  88.4     0.4      M    M
 15000    1.3  34.3   330   15    8   8.3   4.6   31.1  88.0     0.2      M    M
 14500    2.6  36.7   335   14    7   8.9   4.9   30.9  87.6    -0.1    754  3.8
 14000    3.9  39.0   335   13    7   9.0   4.9   30.8  87.4    -0.3    701  3.6
 13500    5.2  41.4   340   12    6   8.7   4.8   30.7  87.2    -0.4    647  3.3
 13000    6.4  43.5   330   11    5   8.5   4.6   30.4  86.8    -0.7    595  3.0
 12500    7.6  45.7   320   10    5   7.7   4.2   30.3  86.5    -0.9    543  2.8
 12000    8.5  47.3   305    8    4   6.2   3.4   29.7  85.5    -1.4    501  2.5
 11500    9.4  48.9   290    7    4   6.0   3.3   29.2  84.5    -2.0    460  2.3
 11000   10.2  50.4   275    6    3   5.4   3.0   28.5  83.3    -2.7    421  2.1
 10500   11.0  51.8   260    6    3   3.0   1.6   27.9  82.2    -3.4    383  1.9
 10250   11.1  52.0   255    5    3   3.8   2.1   27.2  81.0    -4.0    372  1.9
 10000   11.6  52.9   255    5    3   9.0   5.0   27.0  80.7    -4.2    349  1.8
  9750   12.3  54.1   255    5    3   9.3   5.1   27.0  80.6    -4.3    322  1.6
  9500   12.9  55.2   260    5    2   7.9   4.4   26.9  80.5    -4.4    296  1.5
  9250   13.4  56.1   260    5    2   5.3   2.9   26.7  80.0    -4.7    275  1.4
  9000   13.8  56.8   265    5    2   6.7   3.7   26.4  79.4    -5.0    255  1.3
  8750   14.4  57.9   270    5    2   8.5   4.6   26.2  79.2    -5.2    230  1.2
  8500   14.9  58.8   270    5    2   7.2   3.9   26.1  78.9    -5.4    205  1.0
  8250   15.4  59.7   275    5    2   6.1   3.4   25.8  78.5    -5.6    184  0.9
  8000   15.9  60.6   280    5    2   6.4   3.5   25.6  78.0    -5.9    162  0.8
  7750   16.4  61.5   285    5    3   6.9   3.8   25.3  77.6    -6.2    141  0.7
  7500   16.8  62.2   285    5    3   4.5   2.5   25.0  77.1    -6.5    120  0.6
  7250   17.0  62.6   295    6    3   2.4   1.3   24.5  76.1    -7.0    107  0.5
  7000   17.2  63.0   300    6    3   3.1   1.7   24.0  75.2    -7.6     94  0.5
  6750   17.3  63.1   305    7    4   1.8   1.0   23.5  74.2    -8.2     82  0.4
  6500   17.3  63.1   305    7    4  -0.3  -0.2   22.8  73.0    -8.9     74  0.4
  6250   17.3  63.1   310    7    4  -0.4  -0.2   22.0  71.5    -9.8     69  0.4
  6000   17.2  63.0   315    7    4  -1.6  -0.9   21.2  70.1   -10.6     64  0.3
  5750   17.0  62.6   330    8    4  -0.8  -0.4   20.3  68.6   -11.5     61  0.3
  5500   17.1  62.8   310    5    3   4.5   2.5   19.7  67.5   -12.2     53  0.3

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

           07/03/2015 at 0900 MDT          |       07/03/2015 at 1200 MDT
                                           |
K index... +23.7  LI... -1.9               | K index... +10.7  LI... -3.8
CAPE... +246.9  CIN... -147.7              | CAPE... +794.2  CIN... -48.0
                                           |
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 -65.5 -85.9  325  33 17   0.3   0.2 | -65.2 -85.4  330  32 17   0.5   0.3
 45000 -62.2 -80.0  320  55 28   6.2   3.4 | -62.0 -79.6  330  56 29   5.8   3.2
 40000 -52.7 -62.9  315  65 34   7.3   4.0 | -52.4 -62.3  325  70 36   8.1   4.5
 38000 -48.3 -54.9  315  62 32   7.3   4.0 | -47.5 -53.5  325  68 35   8.1   4.5
 36000 -43.3 -45.9  320  59 31   7.7   4.2 | -42.7 -44.9  325  67 34   8.0   4.4
 34000 -38.3 -36.9  320  54 28   8.3   4.6 | -38.2 -36.8  325  60 31   7.4   4.0
 32000 -33.3 -27.9  325  49 25   8.5   4.7 | -33.8 -28.8  325  53 27   7.3   4.0
 30000 -28.9 -20.0  325  43 22   7.3   4.0 | -29.4 -20.9  325  46 24   7.4   4.0
 29000 -26.7 -16.1  325  40 20   7.3   4.0 | -27.2 -17.0  325  42 22   7.4   4.0
 28000 -24.5 -12.1  330  37 19   6.7   3.7 | -24.5 -12.1  325  38 20   6.1   3.3
 27000 -22.5  -8.5  330  34 18   6.6   3.6 | -22.7  -8.9  325  36 18   6.2   3.4
 26000 -20.5  -4.9  335  32 16   6.6   3.6 | -20.8  -5.4  325  33 17   6.2   3.4
 25000 -18.6  -1.5  335  29 15   6.5   3.6 | -19.0  -2.2  325  31 16   6.2   3.4
 24000 -16.7   1.9  335  28 14   6.2   3.4 | -17.2   1.0  325  28 14   6.1   3.4
 23000 -14.8   5.4  335  26 13   6.2   3.4 | -15.3   4.5  325  25 13   6.1   3.4
 22000 -12.9   8.8  335  24 12   6.4   3.5 | -13.5   7.7  330  22 11   6.8   3.7
 21000 -10.9  12.4  330  23 12   6.8   3.8 | -11.3  11.7  330  20 10   7.5   4.1
 20000  -8.9  16.0  330  22 12   6.9   3.8 |  -9.0  15.8  335  18 10   7.5   4.1
 19500  -7.9  17.8  330  22 11   6.8   3.7 |  -7.9  17.8  335  18  9   7.5   4.1
 19000  -6.8  19.8  325  22 11   7.2   3.9 |  -6.7  19.9  340  17  9   8.5   4.7
 18500  -5.2  22.6  325  22 11   7.2   4.0 |  -5.5  22.1  345  17  9   8.4   4.6
 18000  -4.2  24.4  325  22 11   6.9   3.8 |  -4.2  24.4  350  17  9   8.1   4.5
 17500  -3.2  26.2  320  22 11   6.9   3.8 |  -3.0  26.6  345  18  9   7.9   4.4
 17000  -2.2  28.0  320  22 11   6.8   3.7 |  -1.8  28.8  340  19 10   7.9   4.4
 16500  -1.3  29.7  320  21 11   6.6   3.6 |  -0.7  30.7  335  19 10   7.4   4.1
 16000  -0.4  31.3  320  21 11   6.8   3.7 |   0.4  32.7  330  20 10   7.5   4.1
 15500   0.5  32.9  320  19 10   7.0   3.8 |   1.4  34.5  325  20 10   7.0   3.8
 15000   1.4  34.5  320  17  9   7.2   3.9 |   2.9  37.2  325  20 10   7.1   3.9
 14500   2.4  36.3  320  15  8   8.2   4.5 |   3.8  38.8  320  19 10   7.0   3.8
 14000   3.6  38.5  325  13  7   8.4   4.6 |   4.8  40.6  320  17  9   7.2   4.0
 13500   4.7  40.5  330  11  6   8.7   4.8 |   5.7  42.3  320  15  8   7.3   4.0
 13000   6.0  42.8  335  10  5   8.8   4.8 |   6.7  44.1  320  13  7   7.3   4.0
 12500   7.3  45.1  340   9  5   8.5   4.6 |   7.7  45.9  325  10  5   7.7   4.2
 12000   8.5  47.3  340   8  4   7.9   4.4 |   8.8  47.8  330   9  5   8.0   4.4
 11500   9.7  49.5  335   8  4   7.3   4.0 |   9.9  49.8  335   8  4   8.0   4.4
 11000  10.5  50.9  330   7  4   5.6   3.1 |  11.0  51.8  340   7  4   7.7   4.2
 10500  11.3  52.3  325   6  3   3.6   2.0 |  12.2  54.0  340   7  3   3.4   1.9
 10250  11.5  52.7  320   6  3   3.8   2.1 |  12.2  54.0  340   7  3   3.5   1.9
 10000  12.0  53.6  320   5  3   7.6   4.2 |  12.8  55.0  345   6  3   9.3   5.1
  9750  12.5  54.5  315   5  2   7.9   4.3 |  13.4  56.1  345   5  3   8.3   4.5
  9500  13.0  55.4  310   4  2   6.6   3.6 |  13.9  57.0  345   5  2   6.7   3.7
  9250  13.4  56.1  310   4  2   4.5   2.5 |  14.3  57.7  345   4  2   4.7   2.6
  9000  13.8  56.8  305   4  2   6.3   3.5 |  14.7  58.5  350   4  2   6.2   3.4
  8750  14.3  57.7  305   4  2   8.3   4.6 |  15.2  59.4  350   3  2   6.7   3.7
  8500  14.8  58.6  305   4  2   6.6   3.6 |  15.6  60.1  350   3  1   6.7   3.7
  8250  15.2  59.4  305   4  2   5.3   2.9 |  16.0  60.8  350   3  2   6.5   3.6
  8000  15.6  60.1  310   5  2   5.5   3.0 |  16.5  61.7  350   3  2   7.6   4.2
  7750  16.0  60.8  310   5  3   5.3   2.9 |  17.0  62.6  355   3  2   9.2   5.0
  7500  16.4  61.5  310   5  3   3.8   2.1 |  17.6  63.7  355   4  2   9.7   5.3
  7250  16.6  61.9  315   6  3   3.1   1.7 |  18.3  64.9  355   4  2  10.1   5.6
  7000  16.8  62.2  315   7  3   2.7   1.5 |  19.0  66.2  355   4  2   9.6   5.3
  6750  16.9  62.4  315   8  4   3.4   1.9 |  19.7  67.5  355   4  2  10.0   5.5
  6500  17.2  63.0  315   7  4   6.2   3.4 |  20.5  68.9  355   4  2  11.0   6.1
  6250  17.7  63.9  315   7  3   7.0   3.9 |  21.4  70.5  355   4  2  11.9   6.5
  6000  18.1  64.6  315   6  3   6.8   3.8 |  22.2  72.0  355   4  2   9.7   5.3
  5750  18.8  65.8  315   5  3  12.8   7.0 |  23.0  73.4  355   4  2  15.1   8.3
  5500  20.1  68.2  315   5  3  22.2  12.2 |  24.7  76.5  355   4  2  30.1  16.5

           07/03/2015 at 1500 MDT          |       07/03/2015 at 1800 MDT
                                           |
K index... +21.0  LI... -4.7               | K index... +33.4  LI... -4.3
CAPE... +1093.2  CIN... -20.7              | CAPE... +1017.4  CIN... -2.8
                                           |
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 -64.9 -84.8  330  32 16   0.4   0.2 | -65.1 -85.2  320  29 15   0.3   0.2
 45000 -61.8 -79.2  330  49 25   6.0   3.3 | -61.9 -79.4  320  46 24   6.0   3.3
 40000 -52.0 -61.6  315  59 30   8.0   4.4 | -52.1 -61.8  315  63 33   7.7   4.2
 38000 -47.2 -53.0  320  59 30   8.0   4.4 | -47.5 -53.5  315  58 30   7.7   4.2
 36000 -42.4 -44.3  330  60 31   7.9   4.3 | -42.9 -45.2  315  53 27   7.8   4.3
 34000 -37.9 -36.2  325  57 29   7.5   4.1 | -38.0 -36.4  320  51 26   8.2   4.5
 32000 -33.4 -28.1  325  54 28   7.5   4.1 | -33.1 -27.6  325  48 25   8.1   4.4
 30000 -29.1 -20.4  325  49 25   7.0   3.8 | -28.6 -19.5  325  46 23   7.6   4.1
 29000 -26.5 -15.7  320  46 24   7.0   3.8 | -25.8 -14.4  320  44 23   7.6   4.2
 28000 -24.5 -12.1  320  43 22   6.1   3.4 | -23.6 -10.5  320  43 22   6.9   3.8
 27000 -22.6  -8.7  320  40 21   6.2   3.4 | -21.5  -6.7  320  41 21   6.9   3.8
 26000 -20.7  -5.3  320  38 19   6.2   3.4 | -19.5  -3.1  320  39 20   7.0   3.8
 25000 -18.9  -2.0  320  35 18   6.2   3.4 | -17.4   0.7  320  37 19   6.7   3.7
 24000 -17.0   1.4  320  31 16   6.1   3.3 | -15.5   4.1  320  34 17   6.4   3.5
 23000 -15.2   4.6  315  27 14   6.1   3.3 | -13.7   7.3  320  30 16   6.4   3.5
 22000 -13.4   7.9  315  23 12   6.8   3.7 | -11.8  10.8  315  27 14   6.3   3.4
 21000 -11.2  11.8  315  21 11   7.5   4.1 | -10.0  14.0  315  24 12   6.1   3.4
 20000  -8.9  16.0  315  19 10   7.5   4.1 |  -8.2  17.2  310  21 11   6.1   3.4
 19500  -7.8  18.0  315  18  9   7.5   4.1 |  -7.3  18.9  310  19 10   6.1   3.3
 19000  -6.6  20.1  315  17  9   7.9   4.4 |  -6.3  20.7  305  18 10   7.1   3.9
 18500  -5.5  22.1  315  15  8   7.9   4.4 |  -5.3  22.5  305  18  9   7.0   3.8
 18000  -4.3  24.3  315  14  7   8.5   4.7 |  -4.3  24.3  305  18  9   7.1   3.9
 17500  -3.0  26.6  320  14  7   8.9   4.9 |  -3.3  26.1  305  17  9   7.3   4.0
 17000  -1.7  28.9  320  14  7   8.9   4.9 |  -2.3  27.9  305  16  8   7.5   4.1
 16500  -0.4  31.3  325  15  8   8.4   4.6 |  -1.3  29.7  310  15  8   7.1   3.9
 16000   0.8  33.4  325  16  8   8.7   4.8 |  -0.3  31.5  310  14  7   7.2   4.0
 15500   1.9  35.4  325  17  9   7.9   4.4 |   0.7  33.3  310  12  6   7.0   3.8
 15000   3.5  38.3  320  16  8   8.2   4.5 |   2.2  36.0  315   9  5   6.9   3.8
 14500   4.5  40.1  320  16  8   7.4   4.1 |   3.2  37.8  325   7  4   6.2   3.4
 14000   5.5  41.9  320  15  8   7.6   4.1 |   4.0  39.2  330   4  2   6.1   3.4
 13500   6.5  43.7  325  13  7   7.4   4.1 |   5.0  41.0  005   2  1   7.3   4.0
 13000   7.6  45.7  330  11  6   7.3   4.0 |   6.0  42.8  070   2  1   7.9   4.3
 12500   8.7  47.7  340   9  5   6.7   3.7 |   7.1  44.8  100   3  1   8.8   4.8
 12000   9.7  49.5  355   7  4   6.2   3.4 |   8.5  47.3  100   3  1   9.6   5.3
 11500  10.6  51.1  020   6  3   6.6   3.6 |   9.9  49.8  095   3  2   9.7   5.3
 11000  11.6  52.9  040   5  3   7.0   3.9 |  11.3  52.3  090   3  1   9.5   5.2
 10500  12.7  54.9  060   5  2   3.8   2.1 |  12.7  54.9  085   3  1   5.1   2.8
 10250  12.8  55.0  065   5  2   5.7   3.2 |  12.9  55.2  085   3  1   6.6   3.6
 10000  13.4  56.1  065   5  2  11.6   6.3 |  13.8  56.8  085   3  1  13.4   7.3
  9750  14.0  57.2  065   4  2  10.9   6.0 |  14.7  58.5  080   3  1  12.3   6.7
  9500  14.7  58.5  070   4  2   9.5   5.2 |  15.5  59.9  080   3  1  10.0   5.5
  9250  15.2  59.4  070   4  2   8.1   4.4 |  16.1  61.0  075   3  1   7.9   4.3
  9000  15.9  60.6  065   4  2  10.4   5.7 |  16.8  62.2  075   3  1  10.7   5.9
  8750  16.6  61.9  065   4  2  11.3   6.2 |  17.6  63.7  070   3  1  11.7   6.4
  8500  17.4  63.3  065   4  2  10.2   5.6 |  18.5  65.3  070   2  1  10.6   5.8
  8250  18.1  64.6  065   4  2   9.0   4.9 |  19.2  66.6  070   2  1   9.8   5.4
  8000  18.9  66.0  060   4  2  10.2   5.6 |  19.9  67.8  070   2  1   9.6   5.3
  7750  19.7  67.5  060   4  2  11.1   6.1 |  20.6  69.1  065   3  1   9.1   5.0
  7500  20.4  68.7  060   4  2  10.3   5.7 |  21.3  70.3  060   3  1   9.9   5.4
  7250  21.2  70.2  060   4  2  10.0   5.5 |  22.1  71.8  060   2  1  10.5   5.7
  7000  21.9  71.4  060   4  2   9.9   5.4 |  22.9  73.2  055   2  1  10.0   5.5
  6750  22.6  72.7  055   4  2   9.9   5.4 |  23.6  74.5  055   2  1   9.7   5.3
  6500  23.4  74.1  055   3  2  10.5   5.8 |  24.3  75.7  050   2  1  10.3   5.6
  6250  24.2  75.6  055   3  2  11.4   6.3 |  25.1  77.2  050   2  1  11.0   6.0
  6000  25.0  77.0  050   3  2   9.0   4.9 |  25.9  78.6  045   2  1   9.8   5.3
  5750  25.8  78.4  050   3  2  14.7   8.1 |  26.6  79.9  040   2  1  12.4   6.8
  5500  27.5  81.5  050   3  2  31.1  17.1 |  27.8  82.0  045   2  1  20.5  11.3
________________________________________________________________________________

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 near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 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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