Soaring Guidance
Issued by NWS Denver/Boulder, CO

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453
UXUS97 KBOU 091224
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0524 MST Tuesday, February 9, 2016

This forecast is for Tuesday, February 9, 2016:

If the trigger temperature of 55.8 F/13.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 479 ft/min (2.4 m/s)
   Maximum height of thermals.................. 11280 ft MSL (5995 ft AGL)

Forecast maximum temperature................... 58.0 F/14.9 C
Time of trigger temperature.................... 1315 MST
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................. 6744 ft MSL (1459 ft AGL)
Thermal soaring outlook for Wednesday 02/10.... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Little change
Height of stable layer (12-18K ft MSL)......... 16850 ft MSL (11565 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 37025 ft MSL (31740 ft AGL)
Wave soaring outlook for Wednesday 02/10....... Poor

Remarks...

Sunrise/Sunset.................... 06:59:27 / 17:26:58 MST
Total possible sunshine........... 10 hr 27 min 30 sec (627 min 30 sec)
Altitude of sun at 12:13:32 MST... 35.61 degrees

Upper air data from rawinsonde observation taken on 02/09/2016 at 0500 MST

Freezing level.................. 5513 ft MSL (228 ft AGL)
Additional freezing level....... 9816 ft MSL (4531 ft AGL)
Convective condensation level... 20864 ft MSL (15579 ft AGL)
Lifted condensation level....... 16694 ft MSL (11409 ft AGL)
Lifted index.................... +9.6
K index......................... -5.9

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  -57.6 -71.7   330   46   24  -2.1  -1.1  104.7 220.5    51.5      M    M
 45000  -57.9 -72.2   355   66   34   2.8   1.5   78.3 172.9    39.1      M    M
 40000  -62.7 -80.9   320   54   28  -6.4  -3.5   47.6 117.7    21.8      M    M
 38000  -61.5 -78.7   345   72   37   6.4   3.5   40.6 105.0    17.6      M    M
 36000  -57.4 -71.3   345   76   39   7.8   4.3   38.0 100.5    16.4      M    M
 34000  -52.6 -62.7   340   73   38   8.7   4.7   36.6  97.9    15.8      M    M
 32000  -47.6 -53.7   350   71   36   6.7   3.7   35.5  95.9    15.4      M    M
 30000  -43.0 -45.4   355   68   35   6.7   3.7   32.9  91.2    13.9      M    M
 29000  -40.5 -40.9   355   68   35   8.9   4.9   32.1  89.8    13.5      M    M
 28000  -37.9 -36.2   350   68   35   8.9   4.9   31.7  89.0    13.3      M    M
 27000  -35.2 -31.4   350   68   35   8.9   4.9   31.3  88.4    13.2      M    M
 26000  -32.5 -26.5   345   69   35   8.9   4.9   31.1  88.0    13.2      M    M
 25000  -30.0 -22.0   345   69   35   7.0   3.8   30.8  87.4    13.0      M    M
 24000  -27.8 -18.0   345   65   33   8.2   4.5   29.9  85.8    12.5      M    M
 23000  -25.4 -13.7   345   63   32   7.3   4.0   29.3  84.7    12.1      M    M
 22000  -23.5 -10.3   345   61   31   6.2   3.4   27.9  82.2    11.1      M    M
 21000  -21.7  -7.1   345   59   30   6.1   3.4   26.6  79.9    10.1      M    M
 20000  -19.9  -3.8   345   57   29   8.6   4.7   25.3  77.6     9.1      M    M
 19500  -18.7  -1.7   345   54   28   8.2   4.5   25.0  77.0     8.9      M    M
 19000  -17.5   0.5   340   51   26   9.9   5.4   24.8  76.6     8.8      M    M
 18500  -16.1   3.0   340   49   25   6.9   3.8   24.6  76.3     8.7      M    M
 18000  -15.0   5.0   340   48   25   7.7   4.2   24.2  75.6     8.4      M    M
 17500  -14.1   6.6   340   46   24   3.7   2.0   23.6  74.5     7.9      M    M
 17000  -13.5   7.7   335   45   23   1.3   0.7   22.6  72.6     7.1      M    M
 16500  -13.7   7.3   335   44   22  -0.9  -0.5   20.7  69.3     5.4      M    M
 16000  -13.3   8.1   335   42   22   7.7   4.2   19.6  67.3     4.4      M    M
 15500  -12.3   9.9   335   42   21   6.2   3.4   19.1  66.4     4.0      M    M
 15000  -10.7  12.7   340   41   21   7.6   4.2   18.3  65.0     3.4      M    M
 14500   -9.5  14.9   345   40   21   7.9   4.3   18.0  64.5     3.1      M    M
 14000   -8.3  17.1   345   40   21   7.9   4.4   17.7  63.9     2.9      M    M
 13500   -7.2  19.0   345   41   21   5.8   3.2   17.4  63.3     2.6      M    M
 13000   -6.5  20.3   345   42   21   4.9   2.7   16.5  61.8     1.8      M    M
 12500   -5.8  21.6   345   42   22   4.9   2.7   15.7  60.3     1.1      M    M
 12000   -5.1  22.8   345   42   22   6.6   3.6   15.0  59.0     0.4      M    M
 11500   -3.9  25.0   345   38   20   7.9   4.4   14.7  58.4     0.1      M    M
 11000   -2.7  27.1   340   34   18   8.0   4.4   14.4  57.9    -0.2    445  2.3
 10500   -1.5  29.3   340   30   16   8.0   4.4   14.2  57.5    -0.4    394  2.0
 10250   -0.9  30.4   340   28   15   7.7   4.2   14.0  57.2    -0.6    369  1.9
 10000   -0.3  31.5   340   27   14   7.5   4.1   13.8  56.9    -0.7    345  1.8
  9750    0.2  32.4   340   25   13   7.6   4.2   13.7  56.6    -0.9    321  1.6
  9500    0.8  33.4   345   23   12   7.6   4.2   13.5  56.3    -1.1    297  1.5
  9250    1.4  34.5   345   22   11   7.6   4.2   13.4  56.1    -1.2    272  1.4
  9000    1.9  35.4   345   20   10   7.6   4.2   13.2  55.8    -1.4    248  1.3
  8750    2.5  36.5   345   18    9   7.6   4.2   13.0  55.5    -1.6    224  1.1
  8500    3.0  37.4   345   16    8   7.6   4.2   12.9  55.2    -1.7    200  1.0
  8250    3.6  38.5   350   14    7   7.6   4.2   12.7  54.9    -1.9    175  0.9
  8000    4.2  39.6   350   12    6   7.6   4.2   12.5  54.6    -2.1    151  0.8
  7750    4.7  40.5   340   12    6   7.6   4.2   12.4  54.3    -2.3    127  0.6
  7500    5.3  41.5   335   13    6   7.6   4.2   12.2  54.0    -2.4    103  0.5
  7250    5.8  42.4   325   13    7   7.7   4.2   12.0  53.7    -2.6     79  0.4
  7000    6.4  43.5   320   14    7   7.3   4.0   11.9  53.4    -2.8     54  0.3
  6750    7.0  44.6   315   12    6   8.6   4.7   11.7  53.0    -3.0     30  0.2
  6500    7.5  45.5   305   10    5   4.0   2.2   11.5  52.7    -3.2      6  0.0
  6250    7.5  45.5   295    8    4  -3.0  -1.7   10.8  51.4    -4.0      0  0.0
  6000    7.3  45.1   275    7    4   2.3   1.2    9.9  49.8    -4.9      M    M
  5750    6.4  43.5   260    5    3 -43.8 -24.0    8.3  47.0    -6.5     16  0.1
  5500    0.2  32.4   235    4    2 -99.0 -54.3    1.3  34.3   -13.5    197  1.0

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

           02/09/2016 at 0800 MST          |       02/09/2016 at 1100 MST
                                           |
K index... +9.4  LI... +6.0                | K index... +2.8  LI... +6.2
CAPE... 0.0  CIN... -0.0                   | CAPE... 0.0  CIN... -0.6
                                           |
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 -59.3 -74.7  345  46 24   2.7   1.5 | -58.5 -73.3  345  39 20   2.5   1.3
 45000 -55.6 -68.1  350  64 33  -5.7  -3.1 | -55.2 -67.4  355  69 35  -4.9  -2.7
 40000 -62.7 -80.9  340  67 35  -4.8  -2.6 | -61.4 -78.5  335  71 37  -4.2  -2.3
 38000 -61.0 -77.8  340  70 36   7.2   4.0 | -60.1 -76.2  340  70 36   5.9   3.2
 36000 -56.7 -70.1  345  72 37   7.2   4.0 | -56.6 -69.9  345  67 35   5.9   3.2
 34000 -52.2 -62.0  345  73 38   8.1   4.5 | -52.6 -62.7  350  66 34   8.2   4.5
 32000 -47.3 -53.1  345  71 36   8.1   4.5 | -47.0 -52.6  345  64 33   8.3   4.5
 30000 -42.0 -43.6  350  68 35   7.5   4.1 | -42.2 -44.0  345  62 32   7.9   4.3
 29000 -39.8 -39.6  350  68 35   7.5   4.1 | -39.8 -39.6  345  61 31   7.9   4.3
 28000 -37.5 -35.5  350  68 35   7.5   4.1 | -37.4 -35.3  345  60 31   7.9   4.3
 27000 -35.3 -31.5  350  66 34   7.5   4.1 | -35.1 -31.2  345  59 30   7.6   4.2
 26000 -33.1 -27.6  350  63 32   7.5   4.1 | -32.9 -27.2  345  57 30   7.6   4.2
 25000 -30.8 -23.4  345  60 31   7.5   4.1 | -30.6 -23.1  345  56 29   7.6   4.2
 24000 -28.6 -19.5  345  57 29   7.9   4.3 | -28.3 -18.9  345  55 28   7.8   4.3
 23000 -26.2 -15.2  350  57 29   7.9   4.3 | -26.0 -14.8  345  55 28   7.8   4.3
 22000 -23.9 -11.0  350  57 29   7.9   4.3 | -23.7 -10.7  350  55 28   7.8   4.3
 21000 -21.6  -6.9  355  56 29   7.4   4.0 | -21.4  -6.5  350  54 28   6.8   3.7
 20000 -19.4  -2.9  355  55 28   7.4   4.1 | -19.3  -2.7  350  53 27   6.9   3.8
 19500 -18.3  -0.9  355  54 28   7.4   4.1 | -18.3  -0.9  350  52 27   6.9   3.8
 19000 -17.2   1.0  355  54 28   7.5   4.1 | -17.2   1.0  350  51 26   6.9   3.8
 18500 -16.2   2.8  355  53 27   6.1   3.3 | -16.2   2.8  350  51 26   7.0   3.8
 18000 -15.2   4.6  355  51 26   6.2   3.4 | -15.1   4.8  350  50 26   7.0   3.8
 17500 -14.3   6.3  350  49 25   5.4   3.0 | -14.1   6.6  350  50 26   6.6   3.6
 17000 -13.6   7.5  350  48 25   4.9   2.7 | -12.7   9.1  350  49 25   6.4   3.5
 16500 -12.9   8.8  350  47 24   4.9   2.7 | -11.8  10.8  345  48 25   5.7   3.1
 16000 -11.8  10.8  345  45 23   5.6   3.1 | -11.0  12.2  345  47 24   5.6   3.1
 15500 -11.0  12.2  345  43 22   5.9   3.2 | -10.2  13.6  345  46 23   5.7   3.1
 15000 -10.0  14.0  340  42 22   6.4   3.5 |  -9.3  15.3  345  44 23   5.8   3.2
 14500  -8.9  16.0  340  41 21   6.4   3.5 |  -8.5  16.7  345  42 22   5.8   3.2
 14000  -8.0  17.6  340  40 21   5.7   3.1 |  -7.7  18.1  340  40 21   5.2   2.9
 13500  -7.2  19.0  340  39 20   5.7   3.2 |  -6.9  19.6  340  38 20   5.2   2.9
 13000  -6.3  20.7  345  39 20   5.9   3.3 |  -6.0  21.2  340  37 19   5.9   3.3
 12500  -5.5  22.1  350  39 20   5.9   3.2 |  -5.2  22.6  340  35 18   5.9   3.2
 12000  -4.5  23.9  350  38 20   7.3   4.0 |  -4.3  24.3  340  34 17   5.9   3.2
 11500  -3.5  25.7  350  38 19   7.2   3.9 |  -3.4  25.9  340  33 17   5.9   3.3
 11000  -2.5  27.5  350  38 20   6.5   3.5 |  -2.5  27.5  340  33 17   6.9   3.8
 10500  -1.6  29.1  350  39 20   6.7   3.7 |  -1.5  29.3  345  34 18   6.8   3.8
 10250  -1.1  30.0  350  39 20   6.3   3.5 |  -1.1  30.0  345  35 18   4.9   2.7
 10000  -0.6  30.9  350  39 20   8.1   4.4 |  -0.7  30.7  345  35 18   7.0   3.9
  9750   0.1  32.2  350  38 20  10.5   5.7 |  -0.0  32.0  345  35 18  10.9   6.0
  9500   0.9  33.6  350  38 19   9.3   5.1 |   0.8  33.4  350  36 19   9.5   5.2
  9250   1.5  34.7  350  37 19   7.2   4.0 |   1.4  34.5  350  36 19   7.6   4.2
  9000   2.0  35.6  350  35 18   6.8   3.7 |   1.9  35.4  350  35 18   7.3   4.0
  8750   2.5  36.5  350  34 17   7.9   4.3 |   2.5  36.5  350  35 18   9.0   5.0
  8500   3.1  37.6  350  32 16   7.1   3.9 |   3.2  37.8  350  33 17   7.5   4.1
  8250   3.6  38.5  350  29 15   5.8   3.2 |   3.6  38.5  350  31 16   5.3   2.9
  8000   4.0  39.2  350  27 14   6.1   3.3 |   4.0  39.2  350  29 15   5.8   3.2
  7750   4.5  40.1  350  24 13   6.4   3.5 |   4.5  40.1  350  27 14   6.3   3.4
  7500   4.9  40.8  345  22 12   4.9   2.7 |   5.0  41.0  345  24 12   5.8   3.2
  7250   5.2  41.4  340  22 11   3.3   1.8 |   5.4  41.7  345  22 11   4.8   2.6
  7000   5.5  41.9  335  22 11   4.4   2.4 |   5.7  42.3  340  20 10   5.8   3.2
  6750   5.8  42.4  325  22 11   1.7   0.9 |   6.1  43.0  335  18  9   2.6   1.4
  6500   5.6  42.1  320  21 11  -5.6  -3.1 |   6.1  43.0  325  16  8  -2.1  -1.1
  6250   5.1  41.2  310  20 10  -6.0  -3.3 |   5.9  42.6  320  16  8  -0.3  -0.1
  6000   4.6  40.3  300  19 10 -12.5  -6.9 |   5.8  42.4  310  16  8  -6.5  -3.6
  5750   2.9  37.2  290  15  8 -33.3 -18.3 |   4.6  40.3  305  12  6 -21.3 -11.7
  5500  -0.2  31.6  270   9  4 -45.5 -25.0 |   2.7  36.9  285   6  3 -27.0 -14.8

           02/09/2016 at 1400 MST          |       02/09/2016 at 1700 MST
                                           |
K index... -5.4  LI... +5.9                | K index... -9.7  LI... +4.0
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 -59.2 -74.6  335  44 23   2.7   1.5 | -60.3 -76.5  335  45 23   2.7   1.5
 45000 -55.6 -68.1  350  65 33  -4.6  -2.5 | -56.5 -69.7  345  65 33  -2.8  -1.5
 40000 -61.3 -78.3  330  63 32  -3.9  -2.2 | -60.2 -76.4  330  64 33  -2.5  -1.4
 38000 -59.9 -75.8  330  59 31   6.2   3.4 | -58.7 -73.7  330  61 31   5.3   2.9
 36000 -56.2 -69.2  335  53 28   6.2   3.4 | -55.5 -67.9  330  56 29   5.3   2.9
 34000 -52.2 -62.0  340  50 26   7.9   4.3 | -51.9 -61.4  335  54 28   7.6   4.2
 32000 -46.9 -52.4  345  54 28   7.9   4.3 | -47.3 -53.1  340  57 29   7.6   4.2
 30000 -42.2 -44.0  345  55 28   7.6   4.1 | -42.3 -44.1  340  57 29   7.2   4.0
 29000 -40.0 -40.0  345  56 29   7.6   4.1 | -40.1 -40.2  340  56 29   7.2   4.0
 28000 -37.7 -35.9  345  56 29   7.6   4.2 | -38.0 -36.4  340  54 28   7.2   4.0
 27000 -35.4 -31.7  340  55 29   8.0   4.4 | -35.8 -32.4  340  53 27   8.0   4.4
 26000 -33.0 -27.4  340  54 28   8.0   4.4 | -33.4 -28.1  340  52 27   7.9   4.4
 25000 -30.6 -23.1  340  52 27   8.0   4.4 | -31.0 -23.8  340  51 26   7.9   4.4
 24000 -28.3 -18.9  340  51 26   7.3   4.0 | -28.7 -19.7  340  50 26   7.0   3.9
 23000 -26.1 -15.0  345  52 27   7.3   4.0 | -26.6 -15.9  340  50 25   7.1   3.9
 22000 -23.9 -11.0  345  52 27   7.3   4.0 | -24.5 -12.1  340  49 25   7.1   3.9
 21000 -21.8  -7.2  350  52 27   6.4   3.5 | -22.4  -8.3  340  48 25   6.9   3.8
 20000 -19.9  -3.8  350  51 26   6.4   3.5 | -20.3  -4.5  345  47 24   6.9   3.8
 19500 -19.0  -2.2  350  51 26   6.4   3.5 | -19.3  -2.7  345  47 24   6.9   3.8
 19000 -18.0  -0.4  355  51 26   6.4   3.5 | -18.3  -0.9  345  47 24   6.9   3.8
 18500 -17.0   1.4  355  50 26   6.9   3.8 | -17.1   1.2  345  46 24   7.9   4.3
 18000 -16.0   3.2  350  49 25   6.8   3.8 | -16.0   3.2  345  45 23   7.8   4.3
 17500 -14.9   5.2  350  48 25   7.8   4.3 | -14.8   5.4  340  44 23   8.0   4.4
 17000 -13.6   7.5  350  46 24   8.4   4.6 | -13.6   7.5  340  42 21   8.1   4.4
 16500 -11.8  10.8  345  43 22   7.9   4.3 | -12.4   9.7  340  39 20   8.0   4.4
 16000 -10.6  12.9  350  44 23   7.7   4.2 | -10.6  12.9  340  40 20   7.7   4.2
 15500  -9.4  15.1  350  45 23   7.0   3.9 |  -9.4  15.1  345  40 21   7.0   3.8
 15000  -8.5  16.7  350  44 23   6.1   3.3 |  -8.5  16.7  345  41 21   6.1   3.4
 14500  -7.6  18.3  350  44 23   5.9   3.2 |  -7.6  18.3  350  41 21   6.0   3.3
 14000  -6.8  19.8  350  43 22   5.1   2.8 |  -6.8  19.8  350  41 21   5.5   3.0
 13500  -6.1  21.0  350  42 21   5.2   2.9 |  -6.0  21.2  350  41 21   5.6   3.1
 13000  -5.4  22.3  350  40 20   4.6   2.5 |  -5.2  22.6  350  40 21   5.9   3.3
 12500  -4.7  23.5  345  38 19   4.6   2.5 |  -4.3  24.3  355  39 20   6.0   3.3
 12000  -4.0  24.8  345  35 18   4.9   2.7 |  -3.5  25.7  355  38 19   6.3   3.5
 11500  -3.3  26.1  345  33 17   4.9   2.7 |  -2.6  27.3  355  36 18   6.4   3.5
 11000  -2.4  27.7  345  30 16   6.9   3.8 |  -1.7  28.9  355  33 17   5.8   3.2
 10500  -1.4  29.5  350  28 14   6.8   3.7 |  -0.8  30.6  355  31 16   5.8   3.2
 10250  -0.9  30.4  350  27 14   5.2   2.9 |  -0.5  31.1  355  30 15   2.0   1.1
 10000  -0.5  31.1  350  27 14   7.9   4.3 |  -0.3  31.5  355  29 15   6.5   3.6
  9750   0.3  32.5  350  28 14  11.8   6.5 |   0.6  33.1  350  28 15  12.9   7.1
  9500   1.1  34.0  350  28 14   9.8   5.4 |   1.4  34.5  350  28 14   9.9   5.4
  9250   1.7  35.1  350  28 14   7.1   3.9 |   2.0  35.6  350  27 14   7.4   4.1
  9000   2.2  36.0  350  28 14   6.9   3.8 |   2.5  36.5  350  27 14   7.1   3.9
  8750   2.8  37.0  350  27 14   9.7   5.3 |   3.1  37.6  350  26 13   9.4   5.1
  8500   3.5  38.3  350  26 13   8.1   4.5 |   3.8  38.8  345  25 13   7.6   4.1
  8250   3.9  39.0  350  24 12   5.6   3.1 |   4.2  39.6  345  22 11   5.1   2.8
  8000   4.4  39.9  350  21 11   6.2   3.4 |   4.6  40.3  340  19 10   5.6   3.1
  7750   4.8  40.6  345  19 10   7.1   3.9 |   5.0  41.0  335  16  8   6.5   3.6
  7500   5.4  41.7  345  17  9   7.3   4.0 |   5.6  42.1  325  14  7   7.8   4.3
  7250   5.9  42.6  340  16  8   6.4   3.5 |   6.1  43.0  320  14  7   7.6   4.2
  7000   6.4  43.5  330  15  8   7.2   4.0 |   6.7  44.1  310  14  7   8.5   4.7
  6750   6.9  44.4  325  15  8   6.7   3.7 |   7.4  45.3  305  14  7   8.6   4.7
  6500   7.3  45.1  320  14  7   3.7   2.0 |   7.9  46.2  300  14  7   5.9   3.3
  6250   7.5  45.5  320  13  7   4.8   2.7 |   8.3  46.9  300  14  7   6.6   3.6
  6000   7.7  45.9  320  13  6  -2.0  -1.1 |   8.7  47.7  295  14  7   1.4   0.8
  5750   6.8  44.2  310   9  4 -20.0 -11.0 |   8.1  46.6  285  12  6 -17.6  -9.7
  5500   4.8  40.6  285   4  2 -28.1 -15.4 |   6.0  42.8  265   7  4 -32.4 -17.8
________________________________________________________________________________

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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