Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 281318
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0618 MST Wednesday, January 28, 2015

This forecast is for Wednesday, January 28, 2015:

If the trigger temperature of 60.5 F/15.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 225 ft/min (1.1 m/s)
   Maximum height of thermals.................. 8772 ft MSL (3487 ft AGL)

Forecast maximum temperature................... 60.0 F/16.0 C
Time of trigger temperature.................... 1415 MST
Time of overdevelopment........................ 1100 MST
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 5942 ft MSL (656 ft AGL)
Thermal soaring outlook for Thursday 01/29..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Decreasing trend
Height of stable layer (12-18K ft MSL)......... 13660 ft MSL (8375 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 14152 ft MSL (8867 ft AGL)
Wave soaring outlook for Thursday 01/29........ Poor

Remarks... None

Sunrise/Sunset.................... 07:10:53 / 17:12:59 MST
Total possible sunshine........... 10 hr 2 min 5 sec (602 min 5 sec)
Altitude of sun at 12:12:19 MST... 32.16 degrees

Upper air data from rawinsonde observation taken on 01/28/2015 at 0500 MST

Freezing level.................. 10787 ft MSL (5502 ft AGL)
Convective condensation level... 19972 ft MSL (14687 ft AGL)
Lifted condensation level....... 15004 ft MSL (9718 ft AGL)
Lifted index.................... +8.8
K index......................... -11.0

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  -63.7 -82.7   265   30   15   3.4   1.9   91.1 196.0    43.5      M    M
 45000  -55.1 -67.2   265   22   11   7.6   4.2   79.7 175.4    39.6      M    M
 40000  -47.1 -52.8   250   59   30   6.9   3.8   69.4 157.0    35.6      M    M
 38000  -51.2 -60.2   245   67   34  -6.8  -3.7   54.5 130.0    26.4      M    M
 36000  -54.2 -65.6   240   77   39   0.5   0.3   41.6 106.8    18.1      M    M
 34000  -50.6 -59.1   235   73   38   7.6   4.2   38.2 100.8    16.2      M    M
 32000  -45.5 -49.9   235   68   35   7.9   4.3   36.3  97.4    15.3      M    M
 30000  -40.4 -40.7   235   63   32   8.1   4.4   35.2  95.4    14.9      M    M
 29000  -38.0 -36.4   235   62   32   8.0   4.4   34.5  94.1    14.5      M    M
 28000  -35.6 -32.1   230   62   32   8.0   4.4   33.9  93.0    14.2      M    M
 27000  -32.9 -27.2   230   61   31   9.4   5.1   33.5  92.4    14.1      M    M
 26000  -30.1 -22.2   225   60   31   9.4   5.1   33.4  92.1    14.1      M    M
 25000  -27.3 -17.1   225   60   31   9.5   5.2   33.4  92.1    14.3      M    M
 24000  -25.3 -13.5   225   56   29   7.1   3.9   32.2  89.9    13.5      M    M
 23000  -23.1  -9.6   230   53   27   7.3   4.0   31.2  88.1    12.8      M    M
 22000  -21.0  -5.8   235   51   26   7.2   4.0   30.3  86.5    12.2      M    M
 21000  -18.6  -1.5   245   49   25   9.2   5.0   29.6  85.3    11.8      M    M
 20000  -15.9   3.4   250   47   24   9.0   4.9   29.4  84.9    11.8      M    M
 19500  -14.6   5.7   255   47   24   9.0   4.9   29.3  84.7    11.7      M    M
 19000  -13.2   8.2   255   48   24   9.1   5.0   29.1  84.4    11.7      M    M
 18500  -11.9  10.6   260   48   25   9.0   5.0   29.0  84.1    11.6      M    M
 18000  -11.0  12.2   260   49   25   3.0   1.6   28.3  83.0    11.1      M    M
 17500  -10.5  13.1   260   45   23   3.5   1.9   27.2  81.0    10.2      M    M
 17000  -10.0  14.0   260   40   21   3.2   1.8   26.2  79.1     9.3      M    M
 16500   -9.2  15.4   265   35   18   7.9   4.3   25.5  77.8     8.7      M    M
 16000   -8.0  17.6   265   30   16   7.6   4.2   25.1  77.2     8.4      M    M
 15500   -6.3  20.7   265   20   10   7.6   4.1   24.6  76.2     8.0      M    M
 15000   -5.2  22.6   265   13    7   7.5   4.1   24.2  75.6     7.7      M    M
 14500   -4.1  24.6   240    5    3   7.2   4.0   23.8  74.9     7.4      M    M
 14000   -2.9  26.8   150    4    2   2.8   1.6   23.4  74.2     7.1      M    M
 13500   -3.4  25.9   135    2    1  -2.6  -1.4   21.4  70.5     5.2      M    M
 13000   -3.9  25.0   090    1    1  -0.7  -0.4   19.3  66.8     3.3      M    M
 12500   -3.6  25.5   030    2    1   2.4   1.3   18.1  64.6     2.1      M    M
 12000   -3.0  26.6   005    3    1   7.6   4.2   17.3  63.1     1.3      M    M
 11500   -1.7  28.9   305    3    2   8.5   4.7   17.1  62.7     1.1      M    M
 11000   -0.4  31.3   280    5    3   8.6   4.7   16.9  62.4     0.9      M    M
 10500    0.8  33.4   270    9    4   8.6   4.7   16.7  62.0     0.7      M    M
 10250    1.5  34.7   270   10    5   8.5   4.7   16.6  61.8     0.6      M    M
 10000    2.1  35.8   260   14    7   8.5   4.6   16.5  61.7     0.5      M    M
  9750    2.7  36.9   265   15    8   8.4   4.6   16.4  61.5     0.4      M    M
  9500    3.4  38.1   270   15    8   8.5   4.7   16.3  61.3     0.3      M    M
  9250    4.0  39.2   270   16    8   8.3   4.5   16.2  61.1     0.2      M    M
  9000    4.6  40.3   275   17    9   9.0   5.0   16.1  60.9     0.1      M    M
  8750    5.2  41.4   275   22   11   3.9   2.2   15.9  60.6    -0.0    222  1.1
  8500    5.2  41.4   280   26   13  -0.7  -0.4   15.2  59.3    -0.8    214  1.1
  8250    5.3  41.5   280   30   15   5.1   2.8   14.6  58.2    -1.4    203  1.0
  8000    5.9  42.6   280   34   17   8.3   4.5   14.4  57.9    -1.5    179  0.9
  7750    6.4  43.5   280   32   17   7.4   4.1   14.2  57.6    -1.7    155  0.8
  7500    7.0  44.6   280   31   16   7.6   4.2   14.1  57.3    -1.9    131  0.7
  7250    7.6  45.7   275   30   15   7.6   4.2   13.9  57.0    -2.1    106  0.5
  7000    8.1  46.6   275   28   14   7.6   4.2   13.7  56.7    -2.2     82  0.4
  6750    8.7  47.7   275   26   13   7.6   4.2   13.6  56.4    -2.4     58  0.3
  6500    9.3  48.7   275   23   12   7.6   4.2   13.4  56.1    -2.6     33  0.2
  6250    9.8  49.6   275   21   11   7.7   4.2   13.2  55.8    -2.8      9  0.0
  6000   10.4  50.7   275   18    9   7.1   3.9   13.1  55.5    -2.9      M    M
  5750   10.9  51.6   270   12    6   9.3   5.1   12.9  55.2    -3.1      M    M
  5500   11.0  51.8   265    6    3 -16.1  -8.8   12.3  54.1    -3.8      M    M

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

           01/28/2015 at 0800 MST          |       01/28/2015 at 1100 MST
                                           |
K index... -7.0  LI... +8.1                | K index... +2.8  LI... +4.9
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 -62.2 -80.0  260  19 10   4.3   2.3 | -60.7 -77.3  260  22 11   5.1   2.8
 45000 -55.6 -68.1  245  18  9   5.9   3.3 | -53.2 -63.8  260  25 13   4.2   2.3
 40000 -46.4 -51.5  245  37 19   5.8   3.2 | -46.4 -51.5  245  45 23   4.3   2.4
 38000 -46.6 -51.9  245  47 24  -3.2  -1.8 | -46.8 -52.2  245  52 27  -3.5  -1.9
 36000 -48.5 -55.3  245  58 30  -3.2  -1.8 | -48.9 -56.0  245  58 30  -3.5  -1.9
 34000 -49.5 -57.1  245  67 34   3.7   2.0 | -50.0 -58.0  250  64 33   5.6   3.1
 32000 -47.2 -53.0  240  64 33   3.8   2.1 | -46.9 -52.4  250  68 35   5.2   2.9
 30000 -44.4 -47.9  235  62 32   7.8   4.3 | -43.6 -46.5  255  71 37   7.3   4.0
 29000 -42.0 -43.6  240  60 31   7.9   4.3 | -41.4 -42.5  250  70 36   7.3   4.0
 28000 -39.1 -38.4  240  58 30   7.9   4.3 | -38.7 -37.7  250  68 35   7.3   4.0
 27000 -36.7 -34.1  240  57 29   8.8   4.8 | -36.5 -33.7  250  67 34   6.9   3.8
 26000 -34.0 -29.2  245  55 29   8.8   4.8 | -34.5 -30.1  255  62 32   6.8   3.7
 25000 -31.4 -24.5  245  54 28   8.8   4.8 | -32.5 -26.5  255  57 29   6.8   3.7
 24000 -28.8 -19.8  245  52 27   8.7   4.8 | -30.5 -22.9  255  52 27   7.4   4.1
 23000 -26.2 -15.2  245  52 27   8.7   4.8 | -28.0 -18.4  260  49 25   8.1   4.4
 22000 -23.6 -10.5  240  51 26   8.7   4.8 | -25.6 -14.1  260  47 24   8.1   4.5
 21000 -21.0  -5.8  240  50 26   8.4   4.6 | -23.2  -9.8  260  44 23   7.4   4.1
 20000 -18.5  -1.3  240  47 24   8.5   4.6 | -21.0  -5.8  260  40 20   7.3   4.0
 19500 -17.2   1.0  235  46 24   8.5   4.6 | -19.9  -3.8  260  37 19   7.3   4.0
 19000 -15.9   3.4  235  45 23   8.5   4.7 | -18.8  -1.8  255  35 18   7.3   4.0
 18500 -14.7   5.5  235  44 22   7.3   4.0 | -17.8  -0.0  255  33 17   6.7   3.7
 18000 -13.7   7.3  235  41 21   7.0   3.8 | -16.8   1.8  260  30 16   6.4   3.5
 17500 -12.6   9.3  235  38 20   6.8   3.7 | -15.9   3.4  260  27 14   6.5   3.5
 17000 -11.7  10.9  235  36 18   6.2   3.4 | -14.8   5.4  265  26 13   7.2   4.0
 16500 -10.8  12.6  240  33 17   6.4   3.5 | -13.8   7.2  270  25 13   7.2   3.9
 16000  -9.9  14.2  245  31 16   5.1   2.8 | -12.7   9.1  280  25 13   6.9   3.8
 15500  -9.1  15.6  250  28 14   5.1   2.8 | -11.7  10.9  290  27 14   6.9   3.8
 15000  -8.4  16.9  255  26 13   5.3   2.9 | -10.7  12.7  295  30 15   7.1   3.9
 14500  -7.2  19.0  270  27 14   5.5   3.0 |  -9.6  14.7  300  32 16   7.2   3.9
 14000  -6.4  20.5  275  28 14   4.9   2.7 |  -8.0  17.6  305  35 18   6.5   3.6
 13500  -5.7  21.7  280  30 15   4.9   2.7 |  -7.1  19.2  305  37 19   6.5   3.6
 13000  -5.0  23.0  285  32 16   4.7   2.6 |  -6.1  21.0  310  40 20   6.5   3.5
 12500  -4.3  24.3  290  34 18   4.7   2.6 |  -5.2  22.6  310  41 21   6.5   3.5
 12000  -3.7  25.3  295  36 19   4.3   2.3 |  -4.2  24.4  310  42 22   6.4   3.5
 11500  -3.1  26.4  295  38 19   4.2   2.3 |  -3.3  26.1  305  43 22   6.5   3.5
 11000  -2.5  27.5  300  39 20   4.9   2.7 |  -2.4  27.7  305  44 23   5.7   3.1
 10500  -1.7  28.9  300  39 20   5.7   3.1 |  -1.6  29.1  305  44 23   6.0   3.3
 10250  -1.4  29.5  300  39 20   2.4   1.3 |  -1.3  29.7  305  44 22   3.6   2.0
 10000  -1.3  29.7  300  39 20   3.3   1.8 |  -1.1  30.0  305  43 22   4.1   2.3
  9750  -0.8  30.6  300  38 20   7.3   4.0 |  -0.6  30.9  300  42 22   6.7   3.7
  9500  -0.4  31.3  300  37 19   6.4   3.5 |  -0.2  31.6  300  41 21   6.3   3.5
  9250   0.1  32.2  300  36 19   6.1   3.3 |   0.3  32.5  300  40 21   5.6   3.1
  9000   0.5  32.9  300  35 18   5.9   3.3 |   0.6  33.1  300  39 20   5.3   2.9
  8750   1.0  33.8  300  33 17   7.0   3.8 |   1.1  34.0  300  37 19   6.5   3.6
  8500   1.5  34.7  295  31 16   7.1   3.9 |   1.5  34.7  300  34 18   6.7   3.7
  8250   2.0  35.6  295  29 15   7.6   4.2 |   2.0  35.6  295  32 17   6.8   3.8
  8000   2.6  36.7  295  27 14   8.0   4.4 |   2.5  36.5  295  29 15   7.1   3.9
  7750   3.2  37.8  295  25 13   7.6   4.2 |   3.1  37.6  295  27 14   7.6   4.2
  7500   3.7  38.7  295  23 12   8.0   4.4 |   3.6  38.5  295  25 13   7.8   4.3
  7250   4.4  39.9  295  21 11   8.7   4.8 |   4.2  39.6  295  22 12   7.6   4.1
  7000   5.0  41.0  290  19 10   8.8   4.8 |   4.8  40.6  290  20 10   7.6   4.2
  6750   5.7  42.3  290  17  9   8.6   4.7 |   5.3  41.5  290  18  9   6.7   3.7
  6500   6.2  43.2  290  16  8   5.2   2.8 |   5.8  42.4  285  15  8   7.9   4.4
  6250   6.4  43.5  285  14  7   0.5   0.3 |   6.5  43.7  280  13  7   9.8   5.4
  6000   6.5  43.7  275  12  6   8.0   4.4 |   7.2  45.0  275  11  6   8.7   4.8
  5750   7.0  44.6  270  10  5  -5.0  -2.7 |   7.9  46.2  265   9  5  10.4   5.7
  5500   4.8  40.6  255   7  4 -53.5 -29.3 |   8.8  47.8  265   8  4  15.5   8.5

           01/28/2015 at 1400 MST          |       01/28/2015 at 1700 MST
                                           |
K index... +13.9  LI... +1.1               | K index... +10.4  LI... +3.4
CAPE... 0.0  CIN... -0.4                   | CAPE... 0.0  CIN... -0.5
                                           |
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 -60.5 -76.9  250  21 11   5.1   2.8 | -59.9 -75.8  260  21 11   4.2   2.3
 45000 -53.0 -63.4  265  18  9   2.8   1.5 | -53.9 -65.0  275  13  7   1.4   0.8
 40000 -48.6 -55.5  255  50 26   2.9   1.6 | -51.5 -60.7  280  45 23   1.6   0.9
 38000 -47.8 -54.0  260  58 30  -0.1  -0.0 | -51.1 -60.0  285  56 29  -0.1  -0.1
 36000 -47.8 -54.0  265  63 32  -0.1  -0.0 | -51.2 -60.2  290  66 34  -0.1  -0.1
 34000 -47.4 -53.3  270  68 35   3.8   2.1 | -50.9 -59.6  290  75 38   5.7   3.1
 32000 -45.2 -49.4  270  67 35   3.7   2.0 | -47.5 -53.5  300  72 37   5.1   2.8
 30000 -42.9 -45.2  270  65 34   3.9   2.1 | -44.0 -47.2  305  69 36   7.4   4.1
 29000 -41.8 -43.2  270  61 32   3.9   2.1 | -41.8 -43.2  310  67 35   7.5   4.1
 28000 -40.6 -41.1  275  58 30   3.9   2.1 | -39.6 -39.3  315  66 34   7.5   4.1
 27000 -39.5 -39.1  275  54 28   4.3   2.4 | -37.4 -35.3  325  65 33   6.4   3.5
 26000 -37.9 -36.2  280  48 24   5.4   2.9 | -35.6 -32.1  325  59 30   5.8   3.2
 25000 -36.3 -33.3  285  41 21   5.4   2.9 | -33.9 -29.0  325  52 27   5.8   3.2
 24000 -34.7 -30.5  290  36 18   5.8   3.2 | -32.1 -25.8  330  46 24   6.4   3.5
 23000 -32.2 -26.0  295  34 18   8.8   4.8 | -29.9 -21.8  325  42 22   7.6   4.1
 22000 -29.5 -21.1  295  34 18   8.8   4.8 | -27.6 -17.7  320  38 19   7.6   4.2
 21000 -26.9 -16.4  300  34 17   8.7   4.8 | -25.3 -13.5  315  34 18   8.5   4.7
 20000 -24.3 -11.7  300  31 16   8.6   4.7 | -22.7  -8.9  320  34 17   8.7   4.8
 19500 -23.0  -9.4  300  30 15   8.6   4.7 | -21.4  -6.5  320  33 17   8.7   4.8
 19000 -21.8  -7.2  300  28 14   8.6   4.7 | -20.1  -4.2  320  33 17   8.7   4.8
 18500 -20.5  -4.9  300  27 14   8.4   4.6 | -18.9  -2.0  320  33 17   7.7   4.2
 18000 -19.3  -2.7  300  25 13   8.2   4.5 | -17.8  -0.0  320  33 17   7.3   4.0
 17500 -18.0  -0.4  300  23 12   8.1   4.5 | -16.7   1.9  320  32 17   7.2   3.9
 17000 -16.2   2.8  310  24 12   8.5   4.7 | -15.7   3.7  325  31 16   6.7   3.7
 16500 -14.9   5.2  315  26 13   8.5   4.7 | -14.7   5.5  325  31 16   6.7   3.7
 16000 -13.6   7.5  315  27 14   8.6   4.7 | -13.2   8.2  325  30 16   7.2   4.0
 15500 -12.4   9.7  315  29 15   8.6   4.7 | -12.1  10.2  330  30 16   7.2   4.0
 15000 -11.1  12.0  315  31 16   8.1   4.4 | -11.0  12.2  330  31 16   7.8   4.3
 14500  -9.9  14.2  315  32 17   8.1   4.5 |  -9.9  14.2  335  32 16   7.9   4.3
 14000  -8.7  16.3  315  33 17   8.1   4.4 |  -8.8  16.2  335  32 17   6.5   3.6
 13500  -7.5  18.5  315  35 18   8.1   4.5 |  -7.8  18.0  335  33 17   6.6   3.6
 13000  -6.3  20.7  315  36 19   7.5   4.1 |  -6.9  19.6  335  33 17   6.3   3.5
 12500  -5.3  22.5  315  37 19   7.4   4.1 |  -6.0  21.2  335  33 17   6.3   3.5
 12000  -4.2  24.4  315  38 20   7.0   3.8 |  -5.0  23.0  330  32 17   6.3   3.4
 11500  -3.2  26.2  315  39 20   6.9   3.8 |  -4.1  24.6  330  31 16   6.2   3.4
 11000  -2.2  28.0  315  39 20   6.7   3.7 |  -3.2  26.2  330  30 16   7.1   3.9
 10500  -1.2  29.8  310  39 20   7.4   4.1 |  -2.1  28.2  330  29 15   8.3   4.6
 10250  -0.7  30.7  310  39 20   4.0   2.2 |  -1.6  29.1  330  28 14   2.6   1.5
 10000  -0.5  31.1  310  39 20   4.3   2.3 |  -1.6  29.1  330  28 14   3.9   2.1
  9750  -0.0  32.0  310  37 19   7.7   4.2 |  -0.9  30.4  325  27 14  10.3   5.7
  9500   0.5  32.9  305  36 19   7.2   4.0 |  -0.2  31.6  325  27 14   9.2   5.1
  9250   1.0  33.8  305  35 18   5.8   3.2 |   0.4  32.7  325  26 13   7.0   3.8
  9000   1.4  34.5  305  32 17   5.3   2.9 |   0.8  33.4  325  26 13   5.5   3.0
  8750   1.8  35.2  305  30 15   7.4   4.0 |   1.3  34.3  320  25 13   8.0   4.4
  8500   2.4  36.3  305  27 14   7.6   4.2 |   1.9  35.4  320  24 13   8.2   4.5
  8250   2.9  37.2  305  25 13   8.4   4.6 |   2.5  36.5  320  24 12   8.0   4.4
  8000   3.6  38.5  305  23 12   9.1   5.0 |   3.1  37.6  320  22 12   8.1   4.4
  7750   4.3  39.7  305  22 11   9.1   5.0 |   3.7  38.7  320  21 11   8.5   4.6
  7500   5.0  41.0  305  21 11   9.6   5.3 |   4.4  39.9  320  20 10   9.1   5.0
  7250   5.7  42.3  305  20 10  10.1   5.6 |   5.1  41.2  320  19 10   9.4   5.2
  7000   6.5  43.7  305  19 10  10.2   5.6 |   5.7  42.3  315  18  9   9.4   5.2
  6750   7.2  45.0  305  19 10   9.5   5.2 |   6.4  43.5  315  17  9   8.1   4.4
  6500   7.9  46.2  305  18  9  10.0   5.5 |   7.0  44.6  315  16  8   8.4   4.6
  6250   8.7  47.7  310  17  9  11.0   6.1 |   7.7  45.9  315  15  8   9.1   5.0
  6000   9.5  49.1  310  16  8  10.2   5.6 |   8.3  46.9  315  14  7  10.2   5.6
  5750  10.3  50.5  310  15  8  11.5   6.3 |   9.0  48.2  310  13  7   6.1   3.4
  5500  11.3  52.3  310  14  7  15.8   8.6 |   9.0  48.2  310   9  5  -4.9  -2.7
________________________________________________________________________________

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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