Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 051322
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0622 MST Monday, December 5, 2016

This forecast is for Monday, December 5, 2016:

If the trigger temperature of 58.9 F/15.0 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5565 ft MSL (565 ft AGL)

Forecast maximum temperature................... 51.0 F/11.0 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. -32805 ft MSL (-37805 ft AGL)
Thermal soaring outlook for Tuesday 12/06...... Poor

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Decreasing trend
Height of stable layer (12-18K ft MSL)......... 18074 ft MSL (13074 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 19307 ft MSL (14307 ft AGL)
Wave soaring outlook for Tuesday 12/06......... Poor

Remarks... Strong and gusty west winds over front range this morning and
           spreading over plains this afternoon

Sunrise/Sunset.................... 07:06:02 / 16:34:47 MST
Total possible sunshine........... 9 hr 28 min 45 sec (568 min 45 sec)
Altitude of sun at 11:50:25 MST... 27.71 degrees

Upper air data from rawinsonde observation taken on 12/05/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Additional freezing level....... 10082 ft MSL (5082 ft AGL)
Convective condensation level... 17608 ft MSL (12608 ft AGL)
Lifted condensation level....... 13548 ft MSL (8548 ft AGL)
Lifted index.................... +9.8
K index......................... +8.7

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  -59.5 -75.1   265   55   28  -0.6  -0.4  102.4 216.3    52.3      M    M
 45000  -59.7 -75.5   260   76   39   0.2   0.1   76.9 170.5    40.5      M    M
 40000  -56.0 -68.8   245   73   37  -1.7  -1.0   59.6 139.3    32.0      M    M
 38000  -57.2 -71.0   265   71   36  -2.6  -1.4   48.9 120.1    25.8      M    M
 36000  -57.5 -71.5   270   79   41   4.8   2.6   39.9 103.8    20.2      M    M
 34000  -54.8 -66.6   255   72   37   2.6   1.4   35.4  95.7    17.6      M    M
 32000  -52.2 -62.0   255   69   35   8.9   4.9   29.7  85.5    14.0      M    M
 30000  -46.8 -52.2   260   67   34   8.9   4.9   29.2  84.5    13.9      M    M
 29000  -44.2 -47.6   265   66   34   8.9   4.9   28.7  83.7    13.8      M    M
 28000  -41.5 -42.7   265   65   33   8.9   4.9   28.4  83.1    13.7      M    M
 27000  -38.8 -37.8   270   64   33   9.3   5.1   28.2  82.7    13.7      M    M
 26000  -36.0 -32.8   270   63   32   9.3   5.1   28.1  82.5    13.8      M    M
 25000  -33.2 -27.8   265   59   30   9.3   5.1   27.9  82.2    13.8      M    M
 24000  -30.4 -22.7   265   57   29   9.3   5.1   27.7  81.8    13.8      M    M
 23000  -27.6 -17.7   265   56   29   9.0   4.9   27.4  81.3    13.7      M    M
 22000  -24.9 -12.8   260   55   28   9.0   4.9   27.1  80.8    13.7      M    M
 21000  -22.3  -8.1   260   55   28   7.5   4.1   26.7  80.1    13.5      M    M
 20000  -20.1  -4.2   255   55   28   7.7   4.2   26.0  78.8    13.0      M    M
 19500  -18.9  -2.0   255   56   29   8.0   4.4   25.6  78.2    12.8      M    M
 19000  -17.7   0.1   255   57   29   7.9   4.3   25.4  77.6    12.6      M    M
 18500  -16.5   2.3   260   56   29   5.3   2.9   25.1  77.1    12.4      M    M
 18000  -17.4   0.7   265   56   29  -4.6  -2.5   22.4  72.3    10.1      M    M
 17500  -16.7   1.9   270   55   28   5.8   3.2   21.5  70.8     9.4      M    M
 17000  -15.7   3.7   275   54   28   6.6   3.6   21.0  69.7     8.9      M    M
 16500  -14.8   5.4   275   53   28   6.6   3.6   20.4  68.8     8.5      M    M
 16000  -13.8   7.2   280   53   27   6.6   3.6   19.9  67.9     8.1      M    M
 15500  -12.8   9.0   280   52   27   6.6   3.6   19.4  66.9     7.7      M    M
 15000  -11.8  10.8   280   51   26   6.6   3.6   18.9  66.0     7.2      M    M
 14500  -10.8  12.6   280   51   26   6.6   3.6   18.3  65.0     6.8      M    M
 14000   -9.4  15.1   280   51   26   6.7   3.7   17.6  63.6     6.1      M    M
 13500   -8.4  16.9   275   49   25   7.3   4.0   17.0  62.7     5.6      M    M
 13000   -7.2  19.0   270   48   25   8.4   4.6   16.8  62.2     5.4      M    M
 12500   -5.9  21.4   270   48   24   8.4   4.6   16.6  61.8     5.3      M    M
 12000   -4.6  23.7   265   46   24   8.4   4.6   16.4  61.5     5.1      M    M
 11500   -3.4  25.9   265   43   22   8.4   4.6   16.1  61.0     4.9      M    M
 11000   -2.1  28.2   270   39   20   8.4   4.6   15.9  60.6     4.7      M    M
 10500   -0.9  30.4   270   36   19   8.4   4.6   15.7  60.2     4.5      M    M
 10250   -0.3  31.5   270   34   18   8.4   4.6   15.6  60.0     4.4      M    M
 10000    0.4  32.7   275   33   17   8.3   4.5   15.5  59.8     4.3      M    M
  9750    1.0  33.8   275   31   16   8.9   4.9   15.4  59.7     4.3      M    M
  9500    1.7  35.1   275   30   16   9.5   5.2   15.4  59.6     4.2      M    M
  9250    2.4  36.3   280   30   15   9.3   5.1   15.3  59.6     4.2      M    M
  9000    3.1  37.6   280   29   15   9.4   5.1   15.3  59.6     4.2      M    M
  8750    3.8  38.8   280   28   15   9.4   5.1   15.3  59.5     4.2      M    M
  8500    4.5  40.1   280   28   14   9.4   5.1   15.2  59.4     4.2      M    M
  8250    5.2  41.4   280   27   14   9.4   5.2   15.2  59.4     4.2      M    M
  8000    5.9  42.6   280   27   14   9.3   5.1   15.2  59.4     4.1      M    M
  7750    6.6  43.9   280   26   13   9.8   5.4   15.2  59.3     4.1      M    M
  7500    7.3  45.1   280   24   13   7.8   4.3   15.1  59.2     4.1      M    M
  7250    8.0  46.4   275   23   12  15.1   8.3   15.1  59.2     4.1      M    M
  7000    8.7  47.7   275   22   11 -12.0  -6.6   15.1  59.1     4.0      M    M
  6750    9.4  48.9   275   21   11  89.0  48.8   15.0  59.0     4.0      M    M
  6500    9.8  49.6   275   20   10 -99.0 -54.3   14.6  58.3     3.6      M    M
  6250   10.0  50.0   275   19   10 1140.9 625.9   14.1  57.4     3.1      M    M
  6000   10.3  50.5   275   18    9 -99.0 -54.3   13.6  56.6     2.7      M    M
  5750   10.5  50.9   280   13    7 15849.0 8695.4   13.1  55.7     2.2      M    M
  5500    8.2  46.8   285    8    4 -99.0 -54.3   10.1  50.1    -0.9      9  0.0

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

           12/05/2016 at 0800 MST          |       12/05/2016 at 1100 MST
                                           |
CAPE...     0.0    LI...       +5.7        | CAPE...     0.0    LI...       +5.4
CINH...       M    K Index...  -9.8        | CINH...    -0.0    K Index...  -1.5
                                           |
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 -60.2 -76.4  260  67 35   1.0   0.5 | -58.5 -73.3  250  30 15  -1.1  -0.6
 45000 -58.8 -73.8  255  83 43   1.0   0.5 | -60.2 -76.4  245  43 22  -1.1  -0.6
 40000 -58.4 -73.1  265  72 37   0.1   0.1 | -58.2 -72.8  250  38 19   1.7   1.0
 38000 -58.0 -72.4  265  67 35   2.1   1.2 | -56.6 -69.9  255  35 18   3.8   2.1
 36000 -56.7 -70.1  255  63 32   2.2   1.2 | -54.3 -65.7  255  35 18   3.8   2.1
 34000 -55.4 -67.7  250  59 31   2.5   1.4 | -52.0 -61.6  260  35 18   3.9   2.1
 32000 -51.1 -60.0  255  58 30   7.5   4.1 | -49.2 -56.6  260  36 18   4.7   2.6
 30000 -46.7 -52.1  260  58 30   7.6   4.2 | -46.4 -51.5  265  36 19   5.0   2.8
 29000 -43.8 -46.8  260  59 30   7.7   4.2 | -44.5 -48.1  265  36 18   6.8   3.7
 28000 -41.5 -42.7  260  60 31   7.7   4.2 | -42.4 -44.3  265  36 18   6.7   3.7
 27000 -39.1 -38.4  260  61 32   7.7   4.2 | -40.4 -40.7  265  36 18   6.8   3.7
 26000 -36.6 -33.9  260  62 32   8.9   4.9 | -38.3 -36.9  265  35 18   7.0   3.8
 25000 -34.0 -29.2  260  61 32   8.9   4.9 | -36.2 -33.2  265  34 18   7.0   3.8
 24000 -31.3 -24.3  255  61 32   8.9   4.9 | -34.1 -29.4  270  34 17   7.0   3.8
 23000 -28.9 -20.0  255  60 31   7.4   4.1 | -32.0 -25.6  270  33 17   7.1   3.9
 22000 -26.7 -16.1  260  57 30   7.4   4.1 | -29.9 -21.8  270  32 17   7.1   3.9
 21000 -24.5 -12.1  265  55 28   7.4   4.1 | -27.8 -18.0  270  31 16   7.1   3.9
 20000 -22.3  -8.1  265  53 27   7.4   4.1 | -25.1 -13.2  270  30 15   7.2   4.0
 19500 -21.2  -6.2  270  52 27   7.4   4.1 | -24.0 -11.2  270  30 15   7.2   4.0
 19000 -20.1  -4.2  270  51 26   7.4   4.1 | -22.9  -9.2  265  29 15   7.2   4.0
 18500 -18.9  -2.0  270  51 26   7.4   4.0 | -21.8  -7.2  265  29 15   7.2   4.0
 18000 -17.8  -0.0  270  50 26   7.9   4.3 | -20.7  -5.3  265  28 15   7.5   4.1
 17500 -16.6   2.1  275  48 25   8.0   4.4 | -19.6  -3.3  265  28 14   7.5   4.1
 17000 -15.4   4.3  275  46 24   8.1   4.4 | -18.5  -1.3  265  27 14   7.4   4.1
 16500 -14.2   6.4  275  44 23   8.4   4.6 | -17.4   0.7  265  26 14   7.4   4.1
 16000 -12.9   8.8  275  42 22   8.4   4.6 | -16.3   2.7  265  26 13   7.4   4.1
 15500 -11.1  12.0  275  40 21   8.0   4.4 | -15.2   4.6  265  25 13   7.3   4.0
 15000  -9.9  14.2  275  40 20   8.0   4.4 | -14.1   6.6  265  25 13   7.3   4.0
 14500  -8.9  16.0  275  40 21   6.3   3.4 | -13.1   8.4  265  24 12   7.3   4.0
 14000  -7.9  17.8  280  42 21   6.5   3.5 | -12.0  10.4  265  24 12   7.3   4.0
 13500  -7.0  19.4  280  43 22   6.1   3.3 | -10.9  12.4  265  24 12   7.1   3.9
 13000  -6.1  21.0  280  46 24   6.2   3.4 |  -9.9  14.2  265  24 12   7.1   3.9
 12500  -5.3  22.5  280  48 25   3.8   2.1 |  -8.8  16.2  265  24 12   6.3   3.4
 12000  -4.8  23.4  280  49 25   3.5   1.9 |  -7.9  17.8  270  24 12   6.1   3.3
 11500  -4.3  24.3  280  51 26   4.0   2.2 |  -7.1  19.2  270  23 12   5.8   3.2
 11000  -3.7  25.3  280  52 27   4.1   2.3 |  -6.2  20.8  270  23 12   5.7   3.2
 10500  -3.2  26.2  280  52 27   3.4   1.9 |  -5.3  22.5  270  22 11   6.4   3.5
 10250  -3.0  26.6  280  51 26   3.2   1.8 |  -4.9  23.2  270  21 11   6.6   3.6
 10000  -2.7  27.1  280  49 25   3.9   2.1 |  -4.4  24.1  275  21 11   6.8   3.7
  9750  -2.4  27.7  280  48 25   4.6   2.5 |  -3.8  25.2  275  20 10   7.9   4.4
  9500  -2.1  28.2  280  45 23   4.9   2.7 |  -3.2  26.2  275  20 10   8.9   4.9
  9250  -1.7  28.9  280  41 21   5.2   2.9 |  -2.5  27.5  275  19 10   9.8   5.4
  9000  -1.3  29.7  280  38 20   4.4   2.4 |  -1.8  28.8  275  19 10   7.2   3.9
  8750  -1.0  30.2  280  36 18   5.9   3.2 |  -1.4  29.5  275  18  9   6.9   3.8
  8500  -0.5  31.1  280  33 17   7.7   4.2 |  -0.7  30.7  275  18  9   9.4   5.2
  8250   0.1  32.2  280  29 15   8.1   4.5 |  -0.1  31.8  275  17  9   8.8   4.8
  8000   0.7  33.3  280  26 14   5.7   3.1 |   0.6  33.1  275  16  8   9.0   4.9
  7750   1.0  33.8  280  24 12   5.7   3.2 |   1.3  34.3  275  16  8   9.3   5.1
  7500   1.6  34.9  280  21 11   8.2   4.5 |   2.0  35.6  275  16  8   9.4   5.2
  7250   2.2  36.0  280  18  9   7.7   4.2 |   2.7  36.9  275  15  8   9.7   5.3
  7000   2.7  36.9  280  16  8   7.3   4.0 |   3.4  38.1  275  14  7   8.4   4.6
  6750   3.3  37.9  280  14  7   7.6   4.2 |   4.0  39.2  280  14  7   8.9   4.9
  6500   3.9  39.0  280  12  6   9.2   5.1 |   4.8  40.6  280  13  7  10.7   5.9
  6250   4.5  40.1  275  10  5   6.8   3.7 |   5.5  41.9  280  12  6  10.2   5.6
  6000   4.9  40.8  270   9  4   2.2   1.2 |   6.3  43.3  280  12  6  10.9   6.0
  5750   4.4  39.9  260   6  3 -20.4 -11.2 |   7.1  44.8  280  11  6   9.4   5.2
  5500   1.5  34.7  215   4  2 -53.5 -29.3 |   7.8  46.0  280  10  5  10.6   5.8

           12/05/2016 at 1400 MST          |       12/05/2016 at 1700 MST
                                           |
CAPE...     0.0    LI...       +4.3        | CAPE...     0.0    LI...       +5.4
CINH...    -0.0    K Index... -26.6        | CINH...     0.0    K Index... -13.2
                                           |
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 -57.6 -71.7  255  48 25   1.1   0.6 | -59.0 -74.2  255  29 15  -0.6  -0.3
 45000 -55.8 -68.4  255  94 48   1.2   0.6 | -59.9 -75.8  250  41 21  -0.6  -0.3
 40000 -58.0 -72.4  260  75 39  -1.9  -1.0 | -56.4 -69.5  255  39 20   2.9   1.6
 38000 -58.8 -73.8  265  65 33   3.3   1.8 | -54.7 -66.5  260  39 20   2.1   1.1
 36000 -56.6 -69.9  260  71 36   3.3   1.8 | -53.4 -64.1  260  41 21   2.2   1.2
 34000 -54.6 -66.3  255  76 39   3.0   1.6 | -52.1 -61.8  260  42 22   2.2   1.2
 32000 -51.3 -60.3  255  80 41   5.8   3.2 | -50.0 -58.0  260  42 22   4.0   2.2
 30000 -47.8 -54.0  260  83 43   6.1   3.3 | -47.3 -53.1  265  42 21   3.8   2.1
 29000 -45.5 -49.9  265  82 42   8.1   4.4 | -45.5 -49.9  265  41 21   6.5   3.6
 28000 -43.1 -45.6  265  80 41   8.1   4.4 | -43.6 -46.5  265  41 21   6.5   3.6
 27000 -40.6 -41.1  265  79 41   8.1   4.4 | -41.6 -42.9  265  41 21   6.5   3.6
 26000 -38.3 -36.9  270  77 39   6.7   3.7 | -39.7 -39.5  265  40 21   6.1   3.4
 25000 -36.3 -33.3  270  73 38   6.8   3.7 | -37.9 -36.2  270  40 21   6.2   3.4
 24000 -34.2 -29.6  275  70 36   6.8   3.7 | -36.0 -32.8  270  40 21   6.2   3.4
 23000 -32.3 -26.1  275  68 35   5.8   3.2 | -34.1 -29.4  275  40 21   6.4   3.5
 22000 -30.5 -22.9  275  65 34   5.9   3.3 | -32.2 -26.0  275  40 20   6.4   3.5
 21000 -28.7 -19.7  275  63 33   6.0   3.3 | -30.3 -22.5  275  39 20   6.4   3.5
 20000 -26.8 -16.2  275  60 31   6.9   3.8 | -28.4 -19.1  275  38 19   6.5   3.6
 19500 -25.7 -14.3  275  59 30   6.9   3.8 | -27.4 -17.3  275  37 19   6.5   3.6
 19000 -24.7 -12.5  270  57 29   6.9   3.8 | -26.4 -15.5  275  36 19   6.5   3.6
 18500 -23.6 -10.5  270  56 29   7.0   3.8 | -25.4 -13.7  270  36 18   6.6   3.6
 18000 -22.0  -7.6  270  53 28   9.2   5.0 | -24.5 -12.1  270  35 18   6.7   3.7
 17500 -20.6  -5.1  265  53 27   9.1   5.0 | -22.9  -9.2  270  34 17   7.1   3.9
 17000 -19.2  -2.6  265  52 27   9.4   5.1 | -21.8  -7.2  270  33 17   7.0   3.8
 16500 -17.8  -0.0  265  51 26   9.6   5.3 | -20.8  -5.4  270  33 17   6.8   3.7
 16000 -16.3   2.7  265  50 26   9.5   5.2 | -19.8  -3.6  270  32 17   6.8   3.7
 15500 -15.0   5.0  265  49 25   9.0   5.0 | -18.8  -1.8  270  31 16   5.8   3.2
 15000 -13.6   7.5  265  49 25   9.3   5.1 | -18.0  -0.4  270  31 16   6.0   3.3
 14500 -12.4   9.7  265  48 25   7.0   3.8 | -17.2   1.0  270  30 15   4.4   2.4
 14000 -11.3  11.7  265  48 24   7.3   4.0 | -16.5   2.3  270  28 14   4.4   2.4
 13500 -10.3  13.5  265  47 24   5.6   3.1 | -15.9   3.4  265  27 14   4.4   2.4
 13000  -9.5  14.9  265  47 24   5.6   3.1 | -15.3   4.5  265  25 13   4.4   2.4
 12500  -8.8  16.2  265  46 23   3.0   1.7 | -14.5   5.9  265  23 12   6.5   3.6
 12000  -8.5  16.7  265  41 21   2.4   1.3 | -13.5   7.7  265  22 11   7.2   4.0
 11500  -8.1  17.4  265  37 19   3.6   2.0 | -12.3   9.9  265  20 10   8.4   4.6
 11000  -7.5  18.5  270  33 17   3.9   2.2 | -11.0  12.2  265  19 10   8.8   4.8
 10500  -6.9  19.6  270  29 15   6.5   3.6 |  -9.8  14.4  270  18  9   8.4   4.6
 10250  -6.4  20.5  270  27 14   7.0   3.8 |  -9.1  15.6  270  17  9   8.0   4.4
 10000  -5.8  21.6  275  25 13   8.6   4.7 |  -8.5  16.7  270  17  9   9.3   5.1
  9750  -5.1  22.8  275  24 12  10.3   5.7 |  -7.8  18.0  270  16  8  10.4   5.7
  9500  -4.4  24.1  275  23 12   9.9   5.4 |  -7.0  19.4  270  15  8   9.6   5.3
  9250  -3.6  25.5  275  22 12  10.3   5.7 |  -6.3  20.7  275  15  7  10.0   5.5
  9000  -2.9  26.8  275  22 11   9.3   5.1 |  -5.6  21.9  275  14  7   8.6   4.7
  8750  -2.2  28.0  280  21 11   9.0   4.9 |  -5.0  23.0  275  13  7   8.4   4.6
  8500  -1.5  29.3  280  20 10  10.0   5.5 |  -4.3  24.3  280  13  7   9.5   5.2
  8250  -0.8  30.6  280  19 10   9.1   5.0 |  -3.6  25.5  280  12  6   9.3   5.1
  8000  -0.0  32.0  280  19 10  11.5   6.3 |  -2.9  26.8  285  12  6   8.9   4.9
  7750   0.9  33.6  285  18  9  11.0   6.0 |  -2.3  27.9  285  11  6   8.7   4.8
  7500   1.6  34.9  285  18  9   8.4   4.6 |  -1.6  29.1  290  11  5   9.0   4.9
  7250   2.2  36.0  285  17  9   8.9   4.9 |  -0.9  30.4  295  10  5   9.2   5.0
  7000   2.9  37.2  285  17  9   9.4   5.1 |  -0.3  31.5  295  10  5   8.0   4.4
  6750   3.6  38.5  285  16  8  10.2   5.6 |   0.3  32.5  300   9  5   8.0   4.4
  6500   4.4  39.9  290  16  8  10.1   5.6 |   0.9  33.6  305   9  5   9.2   5.1
  6250   5.2  41.4  290  16  8  10.1   5.5 |   1.6  34.9  315   8  4   8.5   4.7
  6000   5.9  42.6  290  15  8  10.6   5.8 |   2.2  36.0  315   8  4   7.9   4.3
  5750   6.7  44.1  290  14  7   9.3   5.1 |   2.8  37.0  320   7  4   7.3   4.0
  5500   7.4  45.3  295  12  6  10.4   5.7 |   3.2  37.8  325   6  3   2.7   1.5
________________________________________________________________________________

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.

CINH (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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