Soaring Guidance
Issued by NWS Denver/Boulder, CO

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175
UXUS97 KBOU 090044
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1744 MST Monday, February 8, 2016

This forecast is for Tuesday, February 9, 2016:

If the trigger temperature of 55.0 F/12.8 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 392 ft/min (2.0 m/s)
   Maximum height of thermals.................. 10656 ft MSL (5349 ft AGL)

Forecast maximum temperature................... 58.0 F/14.9 C
Time of trigger temperature.................... 1230 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................. 7663 ft MSL (2357 ft AGL)
Thermal soaring outlook for Wednesday 02/10.... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 16605 ft MSL (11298 ft AGL)
Wave soaring outlook for Wednesday 02/10....... Poor

Remarks... Large upper ridge west of colorado and large upper trough to the east
           with moderate to strong northwest-northwest flow over the state.

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 numerical model forecast valid on 02/09/2016 at 0500 MST

Freezing level.................. 5594 ft MSL (287 ft AGL)
Additional freezing level....... 9670 ft MSL (4363 ft AGL)
Convective condensation level... 18811 ft MSL (13504 ft AGL)
Lifted condensation level....... 15436 ft MSL (10130 ft AGL)
Lifted index.................... +8.6
K index......................... -6.3

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  -58.6 -73.5   350   56   29   1.5   0.8      M     M       M      M    M
 45000  -56.3 -69.3   350   66   34  -0.9  -0.5      M     M       M      M    M
 40000  -63.3 -81.9   350   61   31  -4.6  -2.5      M     M       M      M    M
 38000  -61.3 -78.3   345   62   32   7.7   4.3      M     M       M      M    M
 36000  -56.7 -70.1   345   65   34   7.7   4.2      M     M       M      M    M
 34000  -52.2 -62.0   345   67   35   7.0   3.8      M     M       M      M    M
 32000  -48.1 -54.6   350   65   34   7.0   3.8      M     M       M      M    M
 30000  -43.6 -46.5   350   63   32   8.3   4.6   32.7  90.8    13.7      M    M
 29000  -40.5 -40.9   350   61   31   8.3   4.6   31.9  89.4    13.3      M    M
 28000  -38.0 -36.4   350   59   30   8.4   4.6   31.4  88.6    13.1      M    M
 27000  -35.5 -31.9   350   57   29   9.0   4.9   31.0  87.8    12.9      M    M
 26000  -32.8 -27.0   350   56   29   8.9   4.9   30.6  87.1    12.8      M    M
 25000  -30.1 -22.2   350   55   28   8.9   4.9   30.3  86.6    12.7      M    M
 24000  -27.6 -17.7   350   54   28   7.1   3.9   30.0  85.9    12.5      M    M
 23000  -25.4 -13.7   350   56   29   7.3   4.0   29.0  84.1    11.9      M    M
 22000  -23.3  -9.9   350   58   30   7.3   4.0   28.1  82.6    11.3      M    M
 21000  -21.2  -6.2   350   58   30   5.8   3.2   27.1  80.7    10.5      M    M
 20000  -19.5  -3.1   345   54   28   5.9   3.2   25.6  78.1     9.4      M    M
 19500  -18.6  -1.5   345   52   27   5.8   3.2   25.0  76.9     8.9      M    M
 19000  -17.7   0.1   340   50   26   5.7   3.2   24.3  75.8     8.4      M    M
 18500  -16.8   1.8   340   47   24   7.0   3.9   23.8  74.8     8.0      M    M
 18000  -15.7   3.7   340   44   23   6.9   3.8   23.3  73.9     7.6      M    M
 17500  -14.7   5.5   340   42   21   7.2   3.9   22.8  73.0     7.3      M    M
 17000  -13.6   7.5   340   44   23   7.3   4.0   22.4  72.3     6.9      M    M
 16500  -12.5   9.5   345   46   24   7.3   4.0   22.0  71.6     6.6      M    M
 16000  -11.5  11.3   345   46   23   6.5   3.5   21.5  70.6     6.1      M    M
 15500  -10.5  13.1   340   44   23   6.5   3.6   20.9  69.7     5.7      M    M
 15000   -9.1  15.6   340   42   21   6.4   3.5   20.1  68.2     5.0      M    M
 14500   -8.1  17.4   340   41   21   6.3   3.4   19.5  67.2     4.5      M    M
 14000   -7.2  19.0   340   39   20   5.9   3.3   18.9  66.1     4.0      M    M
 13500   -6.4  20.5   340   37   19   6.0   3.3   18.3  64.9     3.4      M    M
 13000   -5.4  22.3   340   36   18   6.3   3.5   17.7  63.9     2.9      M    M
 12500   -4.5  23.9   340   35   18   6.4   3.5   17.2  62.9     2.4      M    M
 12000   -3.7  25.3   340   34   17   5.1   2.8   16.5  61.7     1.8      M    M
 11500   -2.9  26.8   345   33   17   5.3   2.9   15.8  60.4     1.1      M    M
 11000   -2.1  28.2   345   32   16   5.6   3.1   15.1  59.2     0.4      M    M
 10500   -1.3  29.7   345   30   16   5.7   3.1   14.4  58.0    -0.3    377  1.9
 10250   -0.9  30.4   345   30   15   3.4   1.9   14.1  57.3    -0.6    359  1.8
 10000   -0.7  30.7   345   29   15   5.1   2.8   13.6  56.4    -1.1    344  1.8
  9750   -0.1  31.8   345   27   14   8.9   4.9   13.4  56.1    -1.3    320  1.6
  9500    0.5  32.9   345   25   13   7.6   4.2   13.3  55.9    -1.4    295  1.5
  9250    0.9  33.6   345   23   12   5.1   2.8   13.0  55.4    -1.7    273  1.4
  9000    1.3  34.3   345   20   11   4.9   2.7   12.6  54.7    -2.1    256  1.3
  8750    1.7  35.1   345   18    9   7.4   4.1   12.3  54.2    -2.3    235  1.2
  8500    2.3  36.1   340   15    8   8.1   4.4   12.2  54.0    -2.5    209  1.1
  8250    2.9  37.2   335   14    7   7.6   4.2   12.0  53.7    -2.6    185  0.9
  8000    3.5  38.3   335   12    6   7.7   4.2   11.9  53.4    -2.8    160  0.8
  7750    4.1  39.4   330   11    6   8.6   4.7   11.8  53.2    -2.9    135  0.7
  7500    4.7  40.5   325   11    6   6.6   3.6   11.6  52.9    -3.1    109  0.6
  7250    5.0  41.0   320   13    7   4.1   2.2   11.2  52.2    -3.5     92  0.5
  7000    5.4  41.7   320   15    8   5.3   2.9   10.9  51.5    -3.9     74  0.4
  6750    5.7  42.3   315   17    9   3.1   1.7   10.5  50.9    -4.3     56  0.3
  6500    5.7  42.3   310   16    8  -3.7  -2.0    9.7  49.5    -5.0     50  0.3
  6250    5.3  41.5   305   15    8  -3.2  -1.8    8.6  47.5    -6.2     54  0.3
  6000    4.9  40.8   295   14    7 -12.6  -6.9    7.5  45.5    -7.3     59  0.3
  5750    2.9  37.2   280   13    6 -39.0 -21.4    4.8  40.7   -10.0    110  0.6
  5500   -0.6  30.9   260    8    4 -51.7 -28.4    0.6  33.0   -14.3    209  1.1

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

           02/09/2016 at 0800 MST          |       02/09/2016 at 1100 MST
                                           |
K index... -14.0  LI... +6.6               | K index... -12.3  LI... +6.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.1
                                           |
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 -59.0 -74.2  350  52 27   1.7   0.9 | -58.7 -73.7  345  45 23   1.5   0.8
 45000 -56.5 -69.7  355  61 32  -1.2  -0.7 | -56.6 -69.9  345  52 27  -3.2  -1.8
 40000 -63.8 -82.8  345  61 31  -4.8  -2.6 | -60.6 -77.1  335  66 34  -2.7  -1.5
 38000 -61.8 -79.2  345  63 33   8.1   4.4 | -59.3 -74.7  340  68 35   5.4   3.0
 36000 -56.9 -70.4  350  67 35   8.0   4.4 | -56.0 -68.8  345  68 35   5.4   3.0
 34000 -52.3 -62.1  350  69 35   7.3   4.0 | -52.5 -62.5  350  67 35   7.3   4.0
 32000 -47.9 -54.2  345  63 32   7.3   4.0 | -47.5 -53.5  350  63 32   7.3   4.0
 30000 -42.7 -44.9  340  60 31   8.3   4.5 | -42.9 -45.2  350  60 31   8.5   4.6
 29000 -40.3 -40.5  340  61 31   8.3   4.5 | -40.3 -40.5  345  61 31   8.5   4.6
 28000 -37.8 -36.0  340  62 32   8.3   4.5 | -37.8 -36.0  345  61 31   8.5   4.6
 27000 -35.3 -31.5  340  62 32   8.2   4.5 | -35.3 -31.5  345  61 31   7.8   4.3
 26000 -32.9 -27.2  340  62 32   8.2   4.5 | -33.0 -27.4  345  60 31   7.9   4.3
 25000 -30.4 -22.7  345  62 32   8.3   4.5 | -30.6 -23.1  340  59 30   7.9   4.3
 24000 -28.1 -18.6  345  61 31   6.1   3.3 | -28.4 -19.1  340  58 30   6.5   3.6
 23000 -26.3 -15.3  345  59 30   6.2   3.4 | -26.4 -15.5  340  54 28   6.5   3.6
 22000 -24.4 -11.9  345  57 29   6.2   3.4 | -24.5 -12.1  345  51 26   6.5   3.6
 21000 -22.5  -8.5  345  53 27   6.6   3.6 | -22.5  -8.5  345  48 24   6.6   3.6
 20000 -20.6  -5.1  345  48 25   6.6   3.6 | -20.5  -4.9  345  44 23   6.6   3.6
 19500 -19.6  -3.3  340  45 23   6.6   3.6 | -19.5  -3.1  345  42 22   6.6   3.6
 19000 -18.6  -1.5  340  42 22   6.4   3.5 | -18.5  -1.3  345  40 21   6.3   3.5
 18500 -17.4   0.7  340  40 21   9.3   5.1 | -17.3   0.9  345  39 20  10.2   5.6
 18000 -16.1   3.0  340  37 19   9.0   4.9 | -15.8   3.6  345  39 20   9.8   5.4
 17500 -14.7   5.5  340  36 18   7.9   4.3 | -14.4   6.1  345  38 20   8.3   4.6
 17000 -13.6   7.5  345  38 20   7.3   4.0 | -12.7   9.1  345  40 20   7.3   4.0
 16500 -12.5   9.5  345  41 21   7.3   4.0 | -11.6  11.1  345  40 21   7.2   3.9
 16000 -11.4  11.5  345  41 21   7.6   4.2 | -10.5  13.1  345  40 20   7.1   3.9
 15500  -9.7  14.5  345  40 20   6.3   3.5 |  -9.5  14.9  345  39 20   6.7   3.7
 15000  -9.0  15.8  345  39 20   4.9   2.7 |  -8.5  16.7  340  39 20   6.1   3.4
 14500  -8.2  17.2  345  39 20   5.1   2.8 |  -7.6  18.3  340  40 21   6.1   3.4
 14000  -7.4  18.7  345  39 20   6.2   3.4 |  -6.7  19.9  340  39 20   6.3   3.5
 13500  -6.5  20.3  345  39 20   6.2   3.4 |  -5.8  21.6  340  39 20   6.3   3.5
 13000  -5.6  21.9  345  38 20   5.8   3.2 |  -4.9  23.2  335  37 19   5.7   3.1
 12500  -4.7  23.5  345  38 20   5.8   3.2 |  -4.0  24.8  335  35 18   5.8   3.2
 12000  -3.8  25.2  345  38 20   6.3   3.5 |  -3.2  26.2  335  34 18   4.9   2.7
 11500  -2.9  26.8  345  38 19   6.3   3.5 |  -2.5  27.5  340  33 17   5.0   2.7
 11000  -2.1  28.2  350  37 19   5.4   3.0 |  -1.8  28.8  340  32 16   5.4   3.0
 10500  -1.3  29.7  350  36 18   5.6   3.1 |  -1.0  30.2  340  30 16   5.4   3.0
 10250  -0.9  30.4  350  35 18   5.6   3.1 |  -0.6  30.9  340  30 15   3.6   2.0
 10000  -0.4  31.3  350  35 18   6.2   3.4 |  -0.4  31.3  340  29 15   4.7   2.6
  9750   0.0  32.0  355  33 17   7.0   3.8 |   0.1  32.2  340  27 14   7.5   4.1
  9500   0.5  32.9  355  31 16   6.5   3.6 |   0.6  33.1  340  25 13   6.6   3.6
  9250   1.0  33.8  355  29 15   5.4   3.0 |   1.1  34.0  340  23 12   5.1   2.8
  9000   1.4  34.5  355  28 14   5.2   2.9 |   1.4  34.5  340  21 11   4.9   2.7
  8750   1.8  35.2  355  25 13   6.0   3.3 |   1.8  35.2  340  19 10   5.7   3.2
  8500   2.2  36.0  355  22 11   5.3   2.9 |   2.3  36.1  335  16  8   6.3   3.5
  8250   2.5  36.5  355  18 10   4.3   2.4 |   2.7  36.9  330  14  7   6.5   3.5
  8000   2.9  37.2  355  15  8   4.3   2.4 |   3.2  37.8  325  12  6   6.3   3.5
  7750   3.2  37.8  355  12  6   5.9   3.2 |   3.7  38.7  315  10  5   8.8   4.8
  7500   3.7  38.7  355  10  5   6.9   3.8 |   4.5  40.1  310  10  5   8.7   4.7
  7250   4.2  39.6  350  11  6   5.5   3.0 |   5.0  41.0  310  11  5   6.4   3.5
  7000   4.6  40.3  345  12  6   7.9   4.3 |   5.5  41.9  305  11  6   7.7   4.2
  6750   5.1  41.2  340  12  6  -0.1  -0.0 |   6.0  42.8  300  12  6   4.8   2.6
  6500   4.6  40.3  325  12  6  -6.9  -3.8 |   6.0  42.8  300  12  6  -2.5  -1.4
  6250   4.3  39.7  315  12  6  -0.5  -0.3 |   5.7  42.3  295  12  6  -3.4  -1.9
  6000   4.0  39.2  305  13  7 -12.0  -6.6 |   5.3  41.5  290  13  7  -7.9  -4.3
  5750   2.1  35.8  290  11  6 -38.1 -20.9 |   4.2  39.6  275  11  5 -21.3 -11.7
  5500  -1.3  29.7  265   6  3 -50.6 -27.7 |   2.2  36.0  255   6  3 -27.5 -15.1

           02/09/2016 at 1400 MST          |       02/09/2016 at 1700 MST
                                           |
K index... -10.7  LI... +7.0               | K index... -18.7  LI... +6.8
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 -59.3 -74.7  345  54 28   3.1   1.7 | -61.1 -78.0  345  57 29   2.5   1.4
 45000 -55.0 -67.0  355  64 33  -3.5  -1.9 | -57.6 -71.7  350  69 36  -1.1  -0.6
 40000 -59.3 -74.7  340  72 37  -3.0  -1.6 | -58.8 -73.8  335  68 35  -0.8  -0.4
 38000 -58.6 -73.5  340  69 36   3.9   2.1 | -57.6 -71.7  335  65 33   3.5   1.9
 36000 -56.3 -69.3  345  62 32   3.9   2.1 | -55.5 -67.9  340  60 31   3.5   1.9
 34000 -53.2 -63.8  350  58 30   8.0   4.4 | -52.6 -62.7  340  55 28   7.9   4.4
 32000 -47.7 -53.9  350  58 30   8.2   4.5 | -47.2 -53.0  340  53 27   8.0   4.4
 30000 -42.7 -44.9  350  57 29   8.7   4.8 | -42.3 -44.1  345  52 27   8.4   4.6
 29000 -40.0 -40.0  355  56 29   8.7   4.8 | -39.8 -39.6  345  51 26   8.4   4.6
 28000 -37.4 -35.3  355  55 28   8.7   4.8 | -37.3 -35.1  345  50 26   8.4   4.6
 27000 -34.9 -30.8  355  54 28   8.0   4.4 | -34.8 -30.6  345  49 25   7.9   4.3
 26000 -32.5 -26.5  350  53 27   8.0   4.4 | -32.4 -26.3  340  46 24   7.9   4.4
 25000 -30.1 -22.2  350  52 27   8.1   4.4 | -30.1 -22.2  335  44 23   8.0   4.4
 24000 -27.8 -18.0  345  52 27   6.0   3.3 | -27.8 -18.0  335  43 22   5.7   3.1
 23000 -26.0 -14.8  345  50 26   6.0   3.3 | -26.1 -15.0  335  45 23   5.8   3.2
 22000 -24.2 -11.6  340  48 25   6.0   3.3 | -24.4 -11.9  340  48 25   5.9   3.2
 21000 -22.3  -8.1  340  46 24   6.8   3.8 | -22.5  -8.5  345  49 25   7.6   4.2
 20000 -20.3  -4.5  340  44 23   6.8   3.7 | -20.2  -4.4  345  48 25   7.5   4.1
 19500 -19.3  -2.7  340  44 22   6.8   3.7 | -19.1  -2.4  345  47 24   7.5   4.1
 19000 -18.3  -0.9  340  43 22   6.5   3.6 | -17.9  -0.2  345  47 24   7.5   4.1
 18500 -17.1   1.2  340  42 22   9.2   5.0 | -16.8   1.8  345  46 24   7.5   4.1
 18000 -15.8   3.6  335  41 21   8.9   4.9 | -15.7   3.7  345  45 23   7.5   4.1
 17500 -14.4   6.1  335  40 20   7.7   4.2 | -14.6   5.7  345  43 22   7.4   4.0
 17000 -13.4   7.9  335  39 20   6.8   3.7 | -13.5   7.7  345  42 22   7.3   4.0
 16500 -11.9  10.6  340  37 19   7.1   3.9 | -11.8  10.8  345  41 21   6.8   3.7
 16000 -10.8  12.6  340  36 18   7.3   4.0 | -10.8  12.6  345  40 21   6.7   3.7
 15500  -9.7  14.5  335  35 18   7.0   3.8 |  -9.8  14.4  345  39 20   6.7   3.7
 15000  -8.7  16.3  335  33 17   6.5   3.5 |  -8.8  16.2  345  39 20   6.7   3.7
 14500  -7.7  18.1  335  31 16   6.4   3.5 |  -7.9  17.8  345  39 20   6.8   3.7
 14000  -6.8  19.8  335  31 16   6.0   3.3 |  -6.8  19.8  350  38 19   7.2   3.9
 13500  -5.9  21.4  335  31 16   6.0   3.3 |  -5.8  21.6  350  36 19   7.2   3.9
 13000  -5.1  22.8  335  31 16   4.7   2.6 |  -4.6  23.7  350  34 18   8.3   4.6
 12500  -4.4  24.1  335  32 16   4.9   2.7 |  -3.4  25.9  350  32 16   8.4   4.6
 12000  -3.8  25.2  335  31 16   3.9   2.1 |  -2.5  27.5  350  29 15   3.6   2.0
 11500  -3.2  26.2  340  31 16   3.9   2.1 |  -1.9  28.6  345  26 13   4.0   2.2
 11000  -2.4  27.7  340  30 15   6.7   3.7 |  -1.3  29.7  350  24 13   5.0   2.7
 10500  -1.5  29.3  345  29 15   6.5   3.6 |  -0.5  31.1  350  24 12   5.0   2.8
 10250  -1.1  30.0  345  28 14   5.0   2.8 |  -0.3  31.5  350  24 12   1.8   1.0
 10000  -0.7  30.7  345  28 14   5.0   2.8 |  -0.1  31.8  350  23 12   5.0   2.8
  9750  -0.3  31.5  345  27 14   6.3   3.4 |   0.5  32.9  350  23 12  10.6   5.8
  9500   0.1  32.2  350  25 13   6.1   3.4 |   1.2  34.2  350  22 11   8.3   4.5
  9250   0.6  33.1  350  24 12   6.0   3.3 |   1.7  35.1  345  20 10   5.1   2.8
  9000   1.0  33.8  350  22 11   6.1   3.3 |   2.0  35.6  345  18 10   4.7   2.6
  8750   1.5  34.7  350  20 10   6.6   3.6 |   2.5  36.5  340  16  8   6.8   3.7
  8500   2.0  35.6  345  17  9   6.6   3.6 |   3.0  37.4  330  14  7   7.8   4.3
  8250   2.5  36.5  345  14  7   6.3   3.5 |   3.6  38.5  325  12  6   8.1   4.4
  8000   3.0  37.4  340  12  6   6.3   3.5 |   4.2  39.6  315  11  6   8.2   4.5
  7750   3.5  38.3  340   9  5   8.0   4.4 |   4.8  40.6  310  11  5   9.7   5.3
  7500   4.1  39.4  330   7  4   8.4   4.6 |   5.5  41.9  305  11  6   7.3   4.0
  7250   4.7  40.5  330   8  4   7.3   4.0 |   5.9  42.6  300  13  6   4.5   2.5
  7000   5.2  41.4  325   8  4   7.7   4.2 |   6.2  43.2  295  14  7   5.6   3.0
  6750   5.7  42.3  320   9  5   7.5   4.1 |   6.6  43.9  295  16  8   4.6   2.5
  6500   6.2  43.2  320   9  5   3.7   2.0 |   6.8  44.2  290  16  8   2.9   1.6
  6250   6.3  43.3  315   9  5   3.2   1.7 |   7.0  44.6  290  14  7   4.0   2.2
  6000   6.4  43.5  310   9  5  -2.2  -1.2 |   7.2  45.0  285  13  7  -0.4  -0.2
  5750   5.5  41.9  300   7  4 -18.3 -10.0 |   6.5  43.7  270  11  5 -18.8 -10.3
  5500   3.7  38.7  270   4  2 -26.0 -14.2 |   4.3  39.7  250   7  4 -35.7 -19.6
________________________________________________________________________________

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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