Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 251329
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0629 MST Sunday, January 25, 2015

This forecast is for Sunday, January 25, 2015:

If the trigger temperature of 51.6 F/10.9 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 396 ft/min (2.0 m/s)
   Maximum height of thermals.................. 12675 ft MSL (7390 ft AGL)

Forecast maximum temperature................... 57.0 F/14.3 C
Time of trigger temperature.................... 1100 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9070 ft MSL (3785 ft AGL)
Thermal soaring outlook for Monday 01/26....... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Little change
Height of stable layer (12-18K ft MSL)......... 17124 ft MSL (11839 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 33155 ft MSL (27870 ft AGL)
Wave soaring outlook for Monday 01/26.......... Poor

Remarks... None

Sunrise/Sunset.................... 07:13:11 / 17:09:27 MST
Total possible sunshine........... 9 hr 56 min 16 sec (596 min 16 sec)
Altitude of sun at 12:11:42 MST... 31.39 degrees

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

Freezing level.................. 5308 ft MSL (23 ft AGL)
Additional freezing level....... 8844 ft MSL (3559 ft AGL)
Convective condensation level... 14162 ft MSL (8877 ft AGL)
Lifted condensation level....... 13849 ft MSL (8563 ft AGL)
Lifted index.................... +5.8
K index......................... +7.4

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  -60.5 -76.9   320   48   25   7.4   4.0   98.7 209.7    48.5      M    M
 45000  -52.3 -62.1   335   48   25   2.9   1.6   87.9 190.2    45.3      M    M
 40000  -51.7 -61.1   345   81   42 -22.9 -12.6   65.7 150.3    33.9      M    M
 38000  -60.1 -76.2   335   94   49   5.6   3.1   44.1 111.5    20.3      M    M
 36000  -56.6 -69.9   350   86   44   6.9   3.8   40.6 105.0    18.4      M    M
 34000  -53.6 -64.5   005  116   60   7.4   4.0   35.4  95.8    15.3      M    M
 32000  -49.7 -57.5   005  117   60   8.9   4.9   32.6  90.7    13.7      M    M
 30000  -44.7 -48.5   360  107   55   8.4   4.6   31.5  88.7    13.2      M    M
 29000  -42.1 -43.8   355  102   53   8.5   4.7   30.9  87.6    12.9      M    M
 28000  -39.6 -39.3   355   98   51   8.5   4.7   30.5  86.8    12.7      M    M
 27000  -37.2 -35.0   350   94   48   5.4   3.0   29.8  85.7    12.4      M    M
 26000  -35.4 -31.7   350   90   47   9.3   5.1   28.4  83.2    11.4      M    M
 25000  -32.7 -26.9   345   87   45   9.0   4.9   28.1  82.6    11.3      M    M
 24000  -30.3 -22.5   350   83   43   8.1   4.4   27.6  81.7    11.0      M    M
 23000  -27.8 -18.0   350   81   42   8.4   4.6   27.0  80.6    10.7      M    M
 22000  -25.9 -14.6   350   78   40   6.0   3.3   25.8  78.5     9.8      M    M
 21000  -23.9 -11.0   350   75   39   6.0   3.3   24.6  76.3     8.9      M    M
 20000  -22.8  -9.0   350   72   37   1.8   1.0   22.5  72.6     7.3      M    M
 19500  -22.3  -8.1   350   71   36   6.4   3.5   21.3  70.4     6.2      M    M
 19000  -21.1  -6.0   345   69   36   8.3   4.6   21.1  70.0     6.1      M    M
 18500  -19.8  -3.6   345   68   35   8.6   4.7   20.9  69.6     5.9      M    M
 18000  -18.4  -1.1   340   68   35   8.9   4.9   20.7  69.3     5.8      M    M
 17500  -17.1   1.2   340   66   34   9.2   5.1   20.6  69.1     5.7      M    M
 17000  -17.6   0.3   335   63   32  -0.6  -0.4   17.5  63.5     3.1      M    M
 16500  -16.6   2.1   330   61   31   6.3   3.4   17.0  62.6     2.6      M    M
 16000  -15.6   3.9   330   58   30   7.0   3.8   16.5  61.7     2.2      M    M
 15500  -14.5   5.9   330   55   28   7.5   4.1   16.1  61.0     1.8      M    M
 15000  -13.4   7.9   330   51   26   7.5   4.1   15.7  60.3     1.4      M    M
 14500  -12.3   9.9   330   48   25   7.4   4.1   15.4  59.6     1.1      M    M
 14000  -11.1  12.0   330   44   23   8.4   4.6   15.1  59.1     0.8      M    M
 13500   -9.9  14.2   330   38   20   8.5   4.7   14.8  58.7     0.6      M    M
 13000   -8.8  16.2   330   32   17   6.4   3.5   14.4  58.0     0.3      M    M
 12500   -7.8  18.0   325   26   14   6.6   3.6   13.9  57.1    -0.2    575  2.9
 12000   -6.8  19.8   325   21   11   6.6   3.6   13.5  56.2    -0.7    531  2.7
 11500   -5.8  21.6   325   22   11   6.6   3.6   12.9  55.3    -1.2    487  2.5
 11000   -4.9  23.2   320   23   12   6.7   3.6   12.4  54.3    -1.7    443  2.2
 10500   -3.9  25.0   320   24   12   6.7   3.7   11.9  53.5    -2.2    399  2.0
 10250   -3.4  25.9   320   25   13   7.7   4.2   11.7  53.1    -2.4    375  1.9
 10000   -2.7  27.1   320   24   13   8.3   4.6   11.6  52.9    -2.5    349  1.8
  9750   -2.1  28.2   320   23   12   8.0   4.4   11.5  52.7    -2.7    324  1.6
  9500   -1.5  29.3   325   22   11   8.1   4.5   11.4  52.5    -2.8    298  1.5
  9250   -0.9  30.4   325   21   11   8.1   4.4   11.2  52.2    -2.9    273  1.4
  9000   -0.3  31.5   325   20   10   8.1   4.4   11.1  52.0    -3.0    248  1.3
  8750    0.3  32.5   320   21   11   8.1   4.5   11.0  51.8    -3.2    222  1.1
  8500    0.9  33.6   315   21   11   8.1   4.5   10.9  51.6    -3.3    197  1.0
  8250    1.5  34.7   315   22   11   8.1   4.5   10.7  51.3    -3.5    171  0.9
  8000    2.1  35.8   310   23   12   8.1   4.5   10.6  51.1    -3.6    146  0.7
  7750    2.7  36.9   305   25   13   8.1   4.5   10.5  50.9    -3.8    121  0.6
  7500    3.3  37.9   305   26   14   8.1   4.5   10.4  50.6    -3.9     95  0.5
  7250    3.9  39.0   300   28   14   8.1   4.4   10.2  50.4    -4.0     70  0.4
  7000    4.5  40.1   300   30   15   8.3   4.6   10.1  50.2    -4.2     44  0.2
  6750    5.1  41.2   300   26   14   7.4   4.0   10.0  50.0    -4.3     19  0.1
  6500    5.5  41.9   300   23   12   3.3   1.8    9.7  49.4    -4.7      M    M
  6250    5.6  42.1   295   19   10   2.7   1.5    9.1  48.3    -5.3      M    M
  6000    5.8  42.4   295   15    8  -1.1  -0.6    8.5  47.3    -5.9      M    M
  5750    5.5  41.9   295   10    5  -2.3  -1.3    7.5  45.5    -6.9      M    M
  5500    5.0  41.0   295    5    3 -16.7  -9.2    6.4  43.4    -8.1      M    M

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

           01/25/2015 at 0800 MST          |       01/25/2015 at 1100 MST
                                           |
K index... +13.5  LI... +6.0               | K index... +9.9  LI... +7.0
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 -57.7 -71.9  305  22 11   5.0   2.8 | -58.9 -74.0  330  24 13   4.0   2.2
 45000 -50.2 -58.4  325  37 19  -0.0  -0.0 | -53.0 -63.4  345  39 20  -1.4  -0.8
 40000 -58.5 -73.3  350  73 38  -5.3  -2.9 | -61.6 -78.9  010  82 42  -5.6  -3.0
 38000 -58.7 -73.7  360  84 43   3.6   2.0 | -60.8 -77.4  010  93 48   5.6   3.1
 36000 -56.5 -69.7  010  93 48   3.7   2.0 | -57.5 -71.5  015 100 51   5.6   3.1
 34000 -53.8 -64.8  015 101 52   8.3   4.5 | -53.6 -64.5  015 103 53   8.9   4.9
 32000 -48.8 -55.8  010  97 50   8.2   4.5 | -48.2 -54.8  015  97 50   9.0   4.9
 30000 -43.9 -47.0  010  92 47   8.0   4.4 | -42.9 -45.2  015  91 47   8.5   4.7
 29000 -41.5 -42.7  010  89 46   8.0   4.4 | -39.7 -39.5  015  84 43   8.5   4.7
 28000 -38.6 -37.5  010  86 44   8.0   4.4 | -37.1 -34.8  015  79 41   8.5   4.7
 27000 -36.2 -33.2  005  84 43   8.3   4.5 | -34.6 -30.3  015  74 38   8.1   4.4
 26000 -33.7 -28.7  005  82 42   8.3   4.5 | -32.2 -26.0  010  70 36   8.1   4.4
 25000 -31.2 -24.2  005  80 41   8.3   4.5 | -29.8 -21.6  005  67 34   8.1   4.4
 24000 -28.8 -19.8  360  77 40   7.9   4.3 | -27.4 -17.3  360  64 33   7.8   4.3
 23000 -26.5 -15.7  355  74 38   7.7   4.2 | -25.1 -13.2  360  60 31   7.8   4.3
 22000 -24.2 -11.6  355  71 37   7.7   4.2 | -22.7  -8.9  355  57 29   7.8   4.3
 21000 -22.0  -7.6  350  68 35   6.8   3.7 | -20.5  -4.9  350  55 28   7.5   4.1
 20000 -19.9  -3.8  345  67 34   6.8   3.8 | -18.2  -0.8  345  53 27   7.5   4.1
 19500 -18.9  -2.0  345  66 34   6.9   3.8 | -17.1   1.2  340  52 27   7.5   4.1
 19000 -17.9  -0.2  345  65 33   6.9   3.8 | -16.0   3.2  340  52 27   7.6   4.2
 18500 -17.0   1.4  345  64 33   5.9   3.2 | -14.9   5.2  335  51 26   6.8   3.7
 18000 -16.1   3.0  340  63 33   5.6   3.1 | -13.9   7.0  335  49 25   6.8   3.7
 17500 -15.3   4.5  340  63 32   5.5   3.0 | -12.9   8.8  330  47 24   6.5   3.6
 17000 -14.6   5.7  340  61 32   4.7   2.6 | -12.0  10.4  330  44 23   6.2   3.4
 16500 -13.9   7.0  340  60 31   4.8   2.6 | -11.1  12.0  325  42 22   6.3   3.5
 16000 -13.2   8.2  340  59 30   4.7   2.6 | -10.4  13.3  330  42 22   3.4   1.8
 15500 -12.5   9.5  340  56 29   4.7   2.6 |  -9.9  14.2  335  44 23   3.7   2.0
 15000 -11.9  10.6  340  55 28   4.7   2.6 |  -9.2  15.4  340  44 23   2.6   1.4
 14500 -10.8  12.6  340  53 27   4.6   2.6 |  -8.8  16.2  340  43 22   2.6   1.4
 14000 -10.1  13.8  345  51 26   4.6   2.5 |  -8.4  16.9  340  42 22   3.2   1.8
 13500  -9.5  14.9  345  50 25   4.5   2.5 |  -8.0  17.6  340  41 21   3.1   1.7
 13000  -8.7  16.3  345  48 25   5.7   3.1 |  -7.5  18.5  345  40 21   4.0   2.2
 12500  -7.9  17.8  345  48 25   5.6   3.1 |  -6.9  19.6  345  39 20   3.6   2.0
 12000  -7.0  19.4  345  47 24   7.2   3.9 |  -6.1  21.0  350  38 20   8.0   4.4
 11500  -5.9  21.4  345  46 24   7.2   4.0 |  -4.9  23.2  350  39 20   7.9   4.3
 11000  -4.7  23.5  345  45 23   8.5   4.7 |  -3.7  25.3  350  39 20   7.6   4.2
 10500  -3.5  25.7  345  43 22   9.6   5.3 |  -2.6  27.3  350  40 20   8.4   4.6
 10250  -2.8  27.0  345  41 21   4.4   2.4 |  -2.1  28.2  345  40 21   3.4   1.9
 10000  -2.7  27.1  345  41 21   4.9   2.7 |  -1.9  28.6  345  40 20   5.7   3.1
  9750  -2.0  28.4  345  39 20  10.8   6.0 |  -1.1  30.0  345  39 20  12.2   6.7
  9500  -1.2  29.8  340  38 19   9.9   5.4 |  -0.3  31.5  345  37 19  10.2   5.6
  9250  -0.5  31.1  340  36 19   7.4   4.0 |   0.4  32.7  345  36 19   7.7   4.2
  9000  -0.1  31.8  340  35 18   5.4   3.0 |   0.9  33.6  345  35 18   6.6   3.6
  8750   0.4  32.7  335  33 17   7.1   3.9 |   1.5  34.7  345  34 17   8.8   4.8
  8500   0.9  33.6  330  32 16   6.8   3.8 |   2.1  35.8  340  32 16   8.2   4.5
  8250   1.4  34.5  330  31 16   5.7   3.1 |   2.7  36.9  335  30 15   6.8   3.7
  8000   1.8  35.2  325  30 15   5.3   2.9 |   3.2  37.8  335  28 15   6.6   3.6
  7750   2.2  36.0  320  30 15   5.7   3.1 |   3.6  38.5  330  27 14   5.8   3.2
  7500   2.6  36.7  315  29 15   4.9   2.7 |   4.0  39.2  325  27 14   4.6   2.5
  7250   2.9  37.2  315  28 14   3.9   2.2 |   4.3  39.7  320  26 13   4.3   2.4
  7000   3.2  37.8  310  27 14   4.2   2.3 |   4.7  40.5  315  26 13   4.2   2.3
  6750   3.5  38.3  310  26 13   4.1   2.3 |   5.0  41.0  310  25 13   4.8   2.6
  6500   3.8  38.8  305  23 12   3.2   1.7 |   5.4  41.7  305  24 12   5.5   3.0
  6250   4.0  39.2  305  21 11   4.6   2.5 |   5.8  42.4  305  21 11   8.1   4.4
  6000   4.3  39.7  300  18  9  -1.7  -0.9 |   6.3  43.3  305  19 10  -0.1  -0.0
  5750   3.5  38.3  295  14  7 -18.5 -10.1 |   5.5  41.9  295  15  8 -17.0  -9.3
  5500   1.7  35.1  275   8  4 -26.8 -14.7 |   4.0  39.2  285   9  5 -20.8 -11.4

           01/25/2015 at 1400 MST          |       01/25/2015 at 1700 MST
                                           |
K index... +6.0  LI... +8.1                | K index... +4.4  LI... +9.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -60.0 -76.0  330  31 16   3.3   1.8 | -62.0 -79.6  340  35 18   2.4   1.3
 45000 -55.5 -67.9  340  52 27  -5.4  -2.9 | -58.8 -73.8  340  53 27  -4.1  -2.3
 40000 -62.4 -80.3  360  73 38  -4.6  -2.5 | -64.2 -83.6  360  66 34  -3.4  -1.9
 38000 -60.9 -77.6  005  76 39   6.2   3.4 | -61.7 -79.1  005  66 34   7.6   4.2
 36000 -57.2 -71.0  005  75 39   6.2   3.4 | -57.1 -70.8  015  64 33   7.6   4.2
 34000 -52.9 -63.2  005  73 38   9.0   4.9 | -52.3 -62.1  015  62 32   8.9   4.9
 32000 -47.5 -53.5  005  69 35   9.0   4.9 | -46.9 -52.4  005  58 30   8.9   4.9
 30000 -41.3 -42.3  360  67 34   9.3   5.1 | -40.9 -41.6  360  52 27   8.9   4.9
 29000 -38.5 -37.3  360  67 34   9.3   5.1 | -38.2 -36.8  360  49 25   8.9   4.9
 28000 -35.7 -32.3  360  67 35   9.3   5.1 | -35.5 -31.9  360  45 23   8.9   4.9
 27000 -33.1 -27.6  360  66 34   8.0   4.4 | -32.9 -27.2  360  44 22   8.5   4.7
 26000 -30.7 -23.3  360  62 32   8.0   4.4 | -30.4 -22.7  355  44 23   8.5   4.7
 25000 -28.3 -18.9  360  58 30   8.0   4.4 | -27.8 -18.0  355  44 23   8.5   4.7
 24000 -25.9 -14.6  360  54 28   7.6   4.2 | -25.3 -13.5  350  44 23   8.4   4.6
 23000 -23.6 -10.5  355  51 26   7.6   4.2 | -22.8  -9.0  350  43 22   8.4   4.6
 22000 -21.3  -6.3  350  48 25   7.7   4.2 | -20.3  -4.5  345  41 21   8.4   4.6
 21000 -19.0  -2.2  345  44 23   8.0   4.4 | -17.7   0.1  340  38 19   9.0   4.9
 20000 -16.6   2.1  340  38 19   8.0   4.4 | -15.0   5.0  330  34 17   9.0   4.9
 19500 -15.4   4.3  335  35 18   8.0   4.4 | -13.6   7.5  325  32 16   9.0   4.9
 19000 -14.3   6.3  330  32 17   8.2   4.5 | -12.3   9.9  320  31 16   9.0   4.9
 18500 -13.2   8.2  330  31 16   6.4   3.5 | -11.1  12.0  315  30 16   6.9   3.8
 18000 -12.2  10.0  330  32 17   6.6   3.6 | -10.1  13.8  320  30 15   7.1   3.9
 17500 -11.3  11.7  335  33 17   6.4   3.5 |  -9.1  15.6  325  30 15   5.3   2.9
 17000 -10.3  13.5  340  35 18   6.3   3.4 |  -8.5  16.7  330  31 16   4.4   2.4
 16500  -9.4  15.1  340  37 19   6.1   3.4 |  -7.8  18.0  335  32 16   4.3   2.4
 16000  -8.6  16.5  340  37 19   4.5   2.5 |  -7.2  19.0  340  32 16   4.4   2.4
 15500  -8.0  17.6  340  36 19   4.8   2.6 |  -6.6  20.1  345  32 16   4.4   2.4
 15000  -7.2  19.0  340  35 18   2.6   1.4 |  -5.7  21.7  350  32 17   3.8   2.1
 14500  -6.9  19.6  340  34 18   2.6   1.4 |  -5.2  22.6  355  33 17   3.9   2.1
 14000  -6.5  20.3  340  34 17   2.6   1.4 |  -4.5  23.9  350  32 16   4.9   2.7
 13500  -6.2  20.8  340  33 17   2.5   1.4 |  -3.8  25.2  350  31 16   4.9   2.7
 13000  -5.7  21.7  345  33 17   3.4   1.9 |  -3.1  26.4  345  29 15   3.7   2.0
 12500  -5.2  22.6  345  32 16   3.0   1.6 |  -2.6  27.3  345  28 15   3.8   2.1
 12000  -4.6  23.7  345  32 16   6.2   3.4 |  -2.0  28.4  340  28 14   3.7   2.0
 11500  -3.7  25.3  345  32 17   5.7   3.1 |  -1.5  29.3  340  27 14   3.6   2.0
 11000  -2.7  27.1  345  33 17   8.1   4.4 |  -0.9  30.4  340  27 14   5.0   2.7
 10500  -1.5  29.3  350  34 17   8.3   4.5 |  -0.2  31.6  345  26 14   5.4   2.9
 10250  -1.0  30.2  350  34 18   3.4   1.9 |   0.1  32.2  345  26 14   2.3   1.3
 10000  -0.9  30.4  345  34 17   6.2   3.4 |   0.3  32.5  345  26 13   4.9   2.7
  9750  -0.0  32.0  345  33 17  12.7   7.0 |   0.9  33.6  345  25 13   9.7   5.3
  9500   0.8  33.4  345  32 17  10.2   5.6 |   1.6  34.9  345  24 12   8.4   4.6
  9250   1.5  34.7  345  31 16   6.8   3.7 |   2.1  35.8  345  22 11   6.8   3.7
  9000   1.9  35.4  345  30 15   5.9   3.2 |   2.6  36.7  340  21 11   6.6   3.6
  8750   2.4  36.3  340  28 14   8.8   4.9 |   3.2  37.8  335  18  9   8.7   4.8
  8500   3.1  37.6  340  26 13   8.0   4.4 |   3.8  38.8  330  16  8   8.6   4.7
  8250   3.6  38.5  335  24 13   6.2   3.4 |   4.5  40.1  325  15  8   8.1   4.5
  8000   4.1  39.4  330  24 12   6.2   3.4 |   5.1  41.2  320  15  8   8.1   4.4
  7750   4.5  40.1  320  23 12   6.6   3.6 |   5.7  42.3  315  16  8   9.7   5.3
  7500   5.0  41.0  315  23 12   6.1   3.4 |   6.4  43.5  310  16  8   7.1   3.9
  7250   5.4  41.7  315  22 11   5.6   3.1 |   6.7  44.1  305  18  9   4.1   2.3
  7000   5.8  42.4  310  22 11   5.5   3.0 |   7.1  44.8  300  19 10   4.9   2.7
  6750   6.3  43.3  305  21 11   6.9   3.8 |   7.4  45.3  295  21 11   4.5   2.5
  6500   6.8  44.2  305  20 10   7.9   4.4 |   7.7  45.9  295  20 10   4.5   2.5
  6250   7.4  45.3  305  18  9   9.8   5.4 |   8.1  46.6  290  18  9   6.4   3.5
  6000   8.1  46.6  305  17  9   2.5   1.4 |   8.4  47.1  290  17  9   0.6   0.3
  5750   7.5  45.5  305  14  7 -12.6  -6.9 |   7.8  46.0  280  13  7 -14.7  -8.1
  5500   6.3  43.3  295   8  4 -15.7  -8.6 |   6.2  43.2  265   8  4 -22.8 -12.5
________________________________________________________________________________

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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