Soaring Guidance
Issued by NWS Denver/Boulder, CO

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820
UXUS97 KBOU 210039
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1739 MST Monday, November 20, 2017

This forecast is for Tuesday, November 21, 2017:

If the trigger temperature of 59.8 F/15.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6768 ft MSL (1424 ft AGL)

Forecast maximum temperature................... 50.0 F/10.5 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5610 ft MSL (266 ft AGL)
Thermal soaring outlook for Wednesday 11/22.... 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)................ Neither
Potential height of wave....................... 17670 ft MSL (12326 ft AGL)
Wave soaring outlook for Wednesday 11/22....... Poor

Remarks... None

Sunrise/Sunset.................... 06:51:27 / 16:39:28 MST
Total possible sunshine........... 9 hr 48 min 1 sec (588 min 1 sec)
Altitude of sun at 11:45:28 MST... 30.06 degrees

Upper air data from numerical model forecast valid on 11/21/2017 at 0500 MST

Freezing level.................. 10723 ft MSL (5379 ft AGL)
Convective condensation level... 14048 ft MSL (8704 ft AGL)
Lifted condensation level....... 11206 ft MSL (5862 ft AGL)
Lifted index.................... +8.3
K index......................... +19.6

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  -61.8 -79.2   330   32   16   1.5   0.8      M     M       M      M    M
 45000  -59.5 -75.1   335   46   24   1.1   0.6      M     M       M      M    M
 40000  -58.0 -72.4   330   60   31   1.0   0.5      M     M       M      M    M
 38000  -55.4 -67.7   330   64   33   5.4   3.0      M     M       M      M    M
 36000  -52.2 -62.0   330   66   34   5.4   3.0      M     M       M      M    M
 34000  -48.7 -55.7   330   66   34   6.2   3.4      M     M       M      M    M
 32000  -45.0 -49.0   325   61   31   6.2   3.4      M     M       M      M    M
 30000  -40.8 -41.4   320   57   29   8.8   4.8   35.6  96.1    19.3      M    M
 29000  -38.2 -36.8   320   56   29   8.8   4.8   35.2  95.3    19.2      M    M
 28000  -35.5 -31.9   320   56   29   8.8   4.8   34.9  94.8    19.1      M    M
 27000  -33.0 -27.4   320   55   28   5.8   3.2   34.5  94.1    19.1      M    M
 26000  -31.6 -24.9   325   51   26   4.8   2.6   32.5  90.4    17.7      M    M
 25000  -30.1 -22.2   325   48   25   4.8   2.6   30.6  87.1    16.4      M    M
 24000  -28.7 -19.7   325   45   23   5.9   3.2   28.9  84.0    15.2      M    M
 23000  -26.4 -15.5   320   40   20   7.7   4.2   28.0  82.4    14.6      M    M
 22000  -24.1 -11.4   315   35   18   7.7   4.2   27.2  81.0    14.2      M    M
 21000  -21.9  -7.4   310   30   16   6.5   3.6   26.5  79.8    13.7      M    M
 20000  -19.6  -3.3   310   28   14   6.2   3.4   24.9  76.8    12.5      M    M
 19500  -18.7  -1.7   310   26   14   6.2   3.4   24.3  75.7    12.0      M    M
 19000  -17.7   0.1   315   25   13   6.0   3.3   23.7  74.7    11.6      M    M
 18500  -16.7   1.9   315   26   13   8.2   4.5   23.3  73.9    11.3      M    M
 18000  -15.5   4.1   315   28   14   7.9   4.4   23.0  73.3    11.1      M    M
 17500  -14.3   6.3   315   30   15   6.0   3.3   22.6  72.7    10.8      M    M
 17000  -13.7   7.3   315   27   14   4.7   2.6   21.7  71.1    10.1      M    M
 16500  -13.0   8.6   315   25   13   4.7   2.6   20.8  69.5     9.3      M    M
 16000  -12.3   9.9   315   23   12   5.2   2.9   20.0  68.1     8.6      M    M
 15500  -11.5  11.3   315   23   12   5.0   2.8   19.3  66.7     8.0      M    M
 15000  -10.7  12.7   320   22   11   6.9   3.8   18.6  65.5     7.4      M    M
 14500   -9.7  14.5   320   21   11   6.7   3.7   18.1  64.6     7.0      M    M
 14000   -8.6  16.5   325   20   10   7.6   4.2   17.7  63.9     6.6      M    M
 13500   -7.5  18.5   330   19   10   7.7   4.2   17.4  63.3     6.3      M    M
 13000   -6.3  20.7   335   19   10   8.6   4.7   17.1  62.7     6.0      M    M
 12500   -5.0  23.0   335   20   10   8.9   4.9   16.9  62.5     5.9      M    M
 12000   -3.6  25.5   340   20   10   9.5   5.2   16.8  62.3     5.9      M    M
 11500   -2.2  28.0   335   22   11   9.7   5.3   16.8  62.3     5.9      M    M
 11000   -0.8  30.6   335   23   12   9.0   5.0   16.8  62.3     5.9      M    M
 10500    0.5  32.9   335   23   12   9.2   5.0   16.6  61.9     5.7      M    M
 10250    1.2  34.2   335   22   12   6.4   3.5   16.5  61.8     5.6      M    M
 10000    1.6  34.9   335   22   11   6.9   3.8   16.2  61.1     5.3      M    M
  9750    2.2  36.0   330   22   11   9.9   5.4   16.2  61.1     5.3      M    M
  9500    2.9  37.2   330   21   11   9.4   5.2   16.1  61.0     5.3      M    M
  9250    3.6  38.5   330   21   11   8.3   4.6   16.1  61.0     5.2      M    M
  9000    4.1  39.4   330   21   11   6.0   3.3   15.9  60.6     5.0      M    M
  8750    4.5  40.1   325   20   10   5.5   3.0   15.5  60.0     4.7      M    M
  8500    5.0  41.0   325   20   10   6.5   3.6   15.2  59.4     4.5      M    M
  8250    5.4  41.7   320   19   10   4.0   2.2   14.9  58.9     4.2      M    M
  8000    5.6  42.1   320   18    9   1.2   0.7   14.3  57.8     3.6      M    M
  7750    5.7  42.3   315   17    9   1.1   0.6   13.7  56.7     3.0      M    M
  7500    5.7  42.3   315   16    8   0.4   0.2   13.0  55.4     2.3      M    M
  7250    5.7  42.3   310   15    8   0.1   0.1   12.3  54.1     1.6      M    M
  7000    5.7  42.3   310   13    7  -0.5  -0.3   11.5  52.7     0.9      M    M
  6750    5.7  42.3   310   11    5   0.6   0.3   10.7  51.3     0.1      M    M
  6500    5.9  42.6   310    9    5   2.4   1.3   10.1  50.2    -0.5    125  0.6
  6250    6.1  43.0   310    7    4   2.6   1.4    9.6  49.2    -1.0    112  0.6
  6000    6.3  43.3   310    5    3   3.3   1.8    9.1  48.3    -1.5     98  0.5
  5750    6.5  43.7   310    3    2   0.8   0.4    8.5  47.3    -2.0     84  0.4
  5500    6.2  43.2   305    2    1 -10.8  -5.9    7.5  45.4    -3.1     86  0.4

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

           11/21/2017 at 0800 MST          |       11/21/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +3.0        | CAPE...     0.0    LI...       +5.3
CINH...     0.0    K Index... +15.8        | CINH...     0.0    K Index...  +6.4
                                           |
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 -60.9 -77.6  325  28 15   2.0   1.1 | -62.9 -81.2  325  33 17   0.4   0.2
 45000 -58.0 -72.4  335  42 22  -0.2  -0.1 | -62.1 -79.8  330  51 26   1.6   0.9
 40000 -58.8 -73.8  340  67 34  -0.3  -0.2 | -59.8 -75.6  350  65 34   1.6   0.9
 38000 -55.9 -68.6  335  69 36   6.9   3.8 | -56.0 -68.8  345  65 33   7.6   4.1
 36000 -51.8 -61.2  335  70 36   6.9   3.8 | -51.5 -60.7  340  62 32   7.6   4.1
 34000 -47.5 -53.5  330  70 36   7.9   4.3 | -46.8 -52.2  340  62 32   8.4   4.6
 32000 -42.7 -44.9  330  69 35   7.9   4.3 | -41.1 -42.0  335  64 33   8.4   4.6
 30000 -38.2 -36.8  325  67 34   6.5   3.5 | -35.7 -32.3  330  65 34   9.3   5.1
 29000 -35.9 -32.6  325  63 32   6.4   3.5 | -32.9 -27.2  330  65 34   9.3   5.1
 28000 -33.9 -29.0  330  60 31   6.4   3.5 | -30.1 -22.2  330  65 34   9.3   5.1
 27000 -32.1 -25.8  330  57 29   6.0   3.3 | -27.7 -17.9  335  64 33   5.6   3.1
 26000 -30.3 -22.5  330  54 28   6.1   3.3 | -26.0 -14.8  335  62 32   5.8   3.2
 25000 -28.5 -19.3  330  51 26   6.1   3.3 | -24.3 -11.7  340  60 31   5.8   3.2
 24000 -26.6 -15.9  335  49 25   6.2   3.4 | -22.7  -8.9  340  57 29   3.8   2.1
 23000 -24.8 -12.6  330  44 22   6.3   3.4 | -21.6  -6.9  340  50 26   3.6   2.0
 22000 -22.9  -9.2  325  39 20   6.3   3.5 | -20.5  -4.9  335  43 22   3.6   2.0
 21000 -21.2  -6.2  320  36 18   4.6   2.5 | -19.5  -3.1  335  38 19   3.4   1.9
 20000 -19.8  -3.6  325  35 18   4.8   2.6 | -18.5  -1.3  330  36 18   3.5   1.9
 19500 -19.1  -2.4  325  35 18   4.8   2.6 | -18.0  -0.4  330  34 18   3.5   1.9
 19000 -18.4  -1.1  325  35 18   4.7   2.6 | -17.5   0.5  330  33 17   3.4   1.8
 18500 -17.6   0.3  325  34 18   5.5   3.0 | -16.9   1.6  330  32 16   5.1   2.8
 18000 -16.8   1.8  325  34 18   5.6   3.1 | -16.1   3.0  325  30 15   5.4   2.9
 17500 -16.0   3.2  325  35 18   5.9   3.2 | -15.3   4.5  325  28 14   5.1   2.8
 17000 -15.0   5.0  325  33 17   6.6   3.6 | -14.6   5.7  325  27 14   4.5   2.5
 16500 -14.0   6.8  325  31 16   6.9   3.8 | -14.0   6.8  325  26 13   4.6   2.5
 16000 -13.2   8.2  325  30 15   4.2   2.3 | -13.4   7.9  325  25 13   3.5   1.9
 15500 -12.6   9.3  320  28 14   4.4   2.4 | -12.8   9.0  325  24 12   3.5   1.9
 15000 -11.9  10.6  320  26 13   5.9   3.2 | -12.1  10.2  325  23 12   6.6   3.6
 14500 -10.9  12.4  320  24 12   6.3   3.5 | -10.5  13.1  320  20 10   7.4   4.1
 14000  -9.5  14.9  320  21 11   6.6   3.6 |  -9.5  14.9  315  19 10   6.8   3.8
 13500  -8.6  16.5  320  20 10   6.6   3.6 |  -8.5  16.7  315  18  9   7.1   3.9
 13000  -7.6  18.3  320  18  9   6.4   3.5 |  -7.6  18.3  310  17  9   5.7   3.1
 12500  -6.7  19.9  325  17  9   6.4   3.5 |  -6.8  19.8  310  15  8   5.9   3.3
 12000  -5.7  21.7  330  16  8   6.8   3.8 |  -6.0  21.2  310  14  7   4.6   2.5
 11500  -4.7  23.5  335  16  8   6.7   3.7 |  -5.3  22.5  315  12  6   4.4   2.4
 11000  -3.6  25.5  340  16  8   8.3   4.6 |  -4.4  24.1  315  10  5   7.6   4.2
 10500  -2.4  27.7  345  15  8   9.4   5.1 |  -3.3  26.1  320   9  5   7.9   4.3
 10250  -1.8  28.8  345  15  8   3.8   2.1 |  -2.9  26.8  325   8  4   3.4   1.8
 10000  -1.7  28.9  345  15  8   4.8   2.6 |  -2.7  27.1  325   8  4   4.6   2.5
  9750  -0.9  30.4  345  15  8  11.8   6.5 |  -2.0  28.4  325   7  4  10.9   6.0
  9500  -0.1  31.8  345  14  7  10.5   5.8 |  -1.3  29.7  330   6  3  10.0   5.5
  9250   0.6  33.1  345  14  7   8.1   4.5 |  -0.6  30.9  330   5  3   7.9   4.3
  9000   1.1  34.0  345  13  7   6.7   3.7 |  -0.0  32.0  330   5  3   7.4   4.1
  8750   1.7  35.1  345  13  6   9.1   5.0 |   0.7  33.3  330   5  2  11.7   6.4
  8500   2.4  36.3  340  12  6   8.6   4.7 |   1.6  34.9  325   4  2  10.4   5.7
  8250   3.0  37.4  335  11  6   6.5   3.6 |   2.1  35.8  325   4  2   6.0   3.3
  8000   3.4  38.1  335  11  5   5.9   3.2 |   2.6  36.7  330   4  2   6.2   3.4
  7750   3.9  39.0  330  10  5   7.3   4.0 |   3.1  37.6  330   3  2   5.7   3.1
  7500   4.4  39.9  325  10  5   5.5   3.0 |   3.5  38.3  345   3  1   5.1   2.8
  7250   4.7  40.5  325   9  5   3.3   1.8 |   3.8  38.8  010   2  1   5.4   2.9
  7000   5.0  41.0  325   8  4   3.5   1.9 |   4.2  39.6  050   2  1   4.5   2.5
  6750   5.3  41.5  325   7  4   4.8   2.7 |   4.6  40.3  080   2  1   7.5   4.1
  6500   5.7  42.3  325   6  3   4.8   2.6 |   5.3  41.5  085   3  1  10.7   5.9
  6250   6.0  42.8  330   5  2   3.4   1.9 |   6.1  43.0  090   3  1  10.5   5.8
  6000   6.2  43.2  330   4  2   3.2   1.7 |   6.9  44.4  090   3  1   9.4   5.2
  5750   6.3  43.3  330   2  1  -4.1  -2.2 |   7.6  45.7  090   3  1  12.4   6.8
  5500   5.5  41.9  280   1  0 -13.4  -7.4 |   8.9  48.0  090   3  1  20.9  11.4

           11/21/2017 at 1400 MST          |       11/21/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +7.3        | CAPE...     0.0    LI...       +9.6
CINH...     0.0    K Index...  +0.2        | CINH...     0.0    K Index...  -7.6
                                           |
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 -65.9 -86.6  320  40 21  -0.7  -0.4 | -68.9 -92.0  320  37 19  -1.7  -0.9
 45000 -66.4 -87.5  320  58 30   3.0   1.7 | -69.8 -93.6  320  51 26   6.8   3.7
 40000 -61.7 -79.1  340  59 30   2.4   1.3 | -59.4 -74.9  330  54 28   6.9   3.8
 38000 -56.4 -69.5  340  58 30   9.6   5.3 | -54.8 -66.6  330  53 27   7.6   4.2
 36000 -50.6 -59.1  340  58 30   9.6   5.3 | -50.3 -58.5  330  50 26   7.6   4.2
 34000 -45.0 -49.0  335  57 29   8.9   4.9 | -44.7 -48.5  330  48 25   8.5   4.7
 32000 -39.0 -38.2  335  55 28   8.9   4.9 | -39.6 -39.3  335  46 24   8.5   4.7
 30000 -33.9 -29.0  335  55 28   8.1   4.4 | -34.4 -29.9  335  43 22   8.9   4.9
 29000 -31.5 -24.7  330  54 28   8.1   4.4 | -31.7 -25.1  330  40 21   8.9   4.9
 28000 -29.1 -20.4  330  54 28   8.0   4.4 | -29.0 -20.2  330  38 20   8.9   4.9
 27000 -26.9 -16.4  330  53 27   7.0   3.8 | -26.7 -16.1  330  38 19   7.0   3.8
 26000 -24.8 -12.6  330  52 27   7.0   3.8 | -24.7 -12.5  330  39 20   7.0   3.8
 25000 -22.7  -8.9  330  50 26   7.0   3.9 | -22.6  -8.7  330  40 20   7.0   3.8
 24000 -20.8  -5.4  330  48 25   5.0   2.7 | -20.6  -5.1  335  40 21   6.2   3.4
 23000 -19.2  -2.6  330  46 24   5.2   2.9 | -18.7  -1.7  335  38 20   6.2   3.4
 22000 -17.7   0.1  340  44 22   5.2   2.8 | -16.9   1.6  340  37 19   6.2   3.4
 21000 -16.2   2.8  340  41 21   3.9   2.1 | -15.2   4.6  340  35 18   4.8   2.6
 20000 -15.0   5.0  340  37 19   3.9   2.2 | -13.7   7.3  345  33 17   4.9   2.7
 19500 -14.4   6.1  340  36 18   3.9   2.2 | -13.0   8.6  345  32 17   4.9   2.7
 19000 -13.8   7.2  335  34 17   4.0   2.2 | -12.2  10.0  345  31 16   4.9   2.7
 18500 -13.3   8.1  335  32 17   2.9   1.6 | -11.5  11.3  345  30 16   4.5   2.5
 18000 -12.9   8.8  335  31 16   3.0   1.7 | -10.8  12.6  345  29 15   4.5   2.5
 17500 -12.5   9.5  330  30 16   3.9   2.1 | -10.1  13.8  340  28 15   5.1   2.8
 17000 -11.7  10.9  330  28 14   4.8   2.7 |  -9.3  15.3  340  28 14   5.5   3.0
 16500 -11.0  12.2  330  26 13   4.9   2.7 |  -8.5  16.7  335  27 14   5.5   3.0
 16000 -10.4  13.3  330  26 13   3.4   1.9 |  -7.7  18.1  335  27 14   5.0   2.7
 15500  -9.9  14.2  330  27 14   3.6   2.0 |  -6.6  20.1  335  26 13   4.1   2.2
 15000  -9.4  15.1  330  27 14   2.6   1.4 |  -6.2  20.8  335  25 13   2.2   1.2
 14500  -9.1  15.6  325  24 13   2.6   1.4 |  -5.9  21.4  335  24 13   2.2   1.2
 14000  -8.4  16.9  320  21 11   4.8   2.6 |  -5.6  21.9  330  23 12   1.7   0.9
 13500  -7.7  18.1  315  19 10   4.5   2.5 |  -5.4  22.3  330  22 11   1.6   0.9
 13000  -6.9  19.6  310  17  9   7.0   3.8 |  -5.1  22.8  330  20 10   2.9   1.6
 12500  -6.0  21.2  310  17  9   6.7   3.7 |  -4.7  23.5  325  18  9   2.8   1.5
 12000  -4.9  23.2  305  16  8   7.4   4.1 |  -4.2  24.4  320  16  8   5.2   2.8
 11500  -3.9  25.0  300  16  8   7.5   4.1 |  -3.5  25.7  315  14  7   4.9   2.7
 11000  -2.9  26.8  300  16  8   6.4   3.3 |  -2.7  27.1  310  13  7   6.8   3.7
 10500  -2.0  28.4  295  15  8   6.3   3.5 |  -1.8  28.8  305  13  7   7.0   3.8
 10250  -1.7  28.9  290  15  8   2.0   1.1 |  -1.4  29.5  300  13  7   2.8   1.5
 10000  -1.6  29.1  290  15  8   2.2   1.2 |  -1.2  29.8  300  13  7   4.1   2.2
  9750  -1.2  29.8  290  13  6   6.9   3.8 |  -0.7  30.7  295  13  7   9.8   5.4
  9500  -0.8  30.6  285  10  5   5.9   3.2 |  -0.0  32.0  290  13  6   8.4   4.6
  9250  -0.4  31.3  280   8  4   3.5   1.9 |   0.5  32.9  290  12  6   5.2   2.8
  9000  -0.2  31.6  280   7  3   3.3   1.8 |   0.8  33.4  285  11  6   4.2   2.3
  8750   0.2  32.4  270   5  2   6.3   3.5 |   1.2  34.2  285  10  5   7.3   4.0
  8500   0.7  33.3  255   2  1   7.8   4.3 |   1.8  35.2  280   8  4   7.3   4.0
  8250   1.3  34.3  240   1  1   7.8   4.3 |   2.3  36.1  275   7  3   5.8   3.2
  8000   1.9  35.4  185   1  0   7.7   4.2 |   2.7  36.9  265   5  3   5.7   3.1
  7750   2.5  36.5  120   1  1  10.7   5.9 |   3.2  37.8  255   4  2   8.2   4.5
  7500   3.4  38.1  110   1  1  10.7   5.9 |   3.9  39.0  240   3  2   8.9   4.9
  7250   4.1  39.4  105   1  1   8.6   4.7 |   4.5  40.1  225   3  1   7.5   4.1
  7000   4.7  40.5  105   2  1   8.7   4.8 |   5.0  41.0  210   3  1   7.3   4.0
  6750   5.4  41.7  105   2  1  11.3   6.2 |   5.6  42.1  185   3  1   9.7   5.3
  6500   6.4  43.5  100   2  1  11.8   6.5 |   6.4  43.5  170   3  1  10.5   5.8
  6250   7.1  44.8  100   2  1  10.0   5.5 |   7.1  44.8  155   3  1   9.1   5.0
  6000   7.9  46.2  095   2  1   9.2   5.1 |   7.8  46.0  145   3  2   8.2   4.5
  5750   8.6  47.5  095   2  1  11.3   6.2 |   8.3  46.9  135   3  2   4.4   2.4
  5500   9.7  49.5  095   2  1  19.4  10.6 |   8.5  47.3  125   3  1   2.9   1.6
________________________________________________________________________________

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.

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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