Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 190017
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0629 MST Saturday, November 18, 2017

This forecast is for Saturday, November 18, 2017:

If the trigger temperature of 37.4 F/3.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 810 ft/min (4.1 m/s)
   Maximum height of thermals.................. 15248 ft MSL (9941 ft AGL)

Forecast maximum temperature................... 49.0 F/9.9 C
Time of trigger temperature.................... 1000 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................. 13611 ft MSL (8304 ft AGL)
Thermal soaring outlook for Sunday 11/19....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 15663 ft MSL (10356 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 26759 ft MSL (21452 ft AGL)
Wave soaring outlook for Sunday 11/19.......... Poor

Remarks...

Sunrise/Sunset.................... 06:47:56 / 16:41:26 MST
Total possible sunshine........... 9 hr 53 min 31 sec (593 min 31 sec)
Altitude of sun at 11:44:52 MST... 30.88 degrees

Upper air data from numerical model forecast valid on 11/18/2017 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 10199 ft MSL (4892 ft AGL)
Lifted condensation level....... 12562 ft MSL (7256 ft AGL)
Lifted index.................... +6.2
K index......................... -4.8

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  -59.6 -75.3   275   68   35   3.0   1.6      M     M       M      M    M
 45000  -55.1 -67.2   275   74   38   3.0   1.7      M     M       M      M    M
 40000  -50.2 -58.4   280   75   39   3.3   1.8      M     M       M      M    M
 38000  -48.7 -55.7   285   75   39   0.6   0.4      M     M       M      M    M
 36000  -48.3 -54.9   290   71   37   0.6   0.3      M     M       M      M    M
 34000  -48.0 -54.4   295   68   35   2.0   1.1      M     M       M      M    M
 32000  -46.0 -50.8   305   65   33   3.3   1.8      M     M       M      M    M
 30000  -44.0 -47.2   315   64   33   3.9   2.1      M     M       M      M    M
 29000  -42.6 -44.7   320   65   33   4.7   2.6   32.1  89.9    17.1      M    M
 28000  -41.2 -42.2   325   66   34   4.7   2.6   30.1  86.2    15.8      M    M
 27000  -39.8 -39.6   330   67   35   4.7   2.6   28.2  82.8    14.5      M    M
 26000  -38.2 -36.8   335   68   35   6.0   3.3   26.5  79.8    13.4      M    M
 25000  -36.4 -33.5   335   67   35   6.1   3.3   25.1  77.1    12.4      M    M
 24000  -34.6 -30.3   340   67   34   6.1   3.3   23.7  74.7    11.5      M    M
 23000  -32.7 -26.9   340   66   34   6.4   3.5   22.4  72.4    10.6      M    M
 22000  -30.8 -23.4   345   65   33   6.4   3.5   21.1  70.1     9.6      M    M
 21000  -28.9 -20.0   345   64   33   6.5   3.6   20.0  68.0     8.8      M    M
 20000  -27.3 -17.1   345   62   32   4.5   2.5   18.3  65.0     7.5      M    M
 19500  -26.6 -15.9   345   60   31   4.5   2.5   17.4  63.3     6.7      M    M
 19000  -26.0 -14.8   345   59   30   4.5   2.5   16.5  61.6     6.0      M    M
 18500  -25.3 -13.5   345   58   30   4.6   2.5   15.6  60.1     5.3      M    M
 18000  -24.4 -11.9   345   53   27   3.6   2.0   14.1  57.5     4.1      M    M
 17500  -23.8 -10.8   335   48   25   3.5   1.9   13.1  55.6     3.2      M    M
 17000  -23.1  -9.6   330   45   23   6.1   3.3   12.2  54.0     2.4      M    M
 16500  -22.2  -8.0   330   43   22   6.1   3.4   11.6  52.9     1.9      M    M
 16000  -21.3  -6.3   325   41   21   4.4   2.4   10.9  51.7     1.3      M    M
 15500  -20.8  -5.4   325   39   20   3.5   1.9    9.9  49.7     0.3      M    M
 15000  -20.3  -4.5   320   37   19   3.6   2.0    8.8  47.9    -0.6    791  4.0
 14500  -19.8  -3.6   315   35   18   3.7   2.0    7.8  46.0    -1.6    760  3.9
 14000  -19.3  -2.7   315   33   17   4.3   2.4    6.8  44.2    -2.5    729  3.7
 13500  -18.5  -1.3   320   32   17   6.2   3.4    6.1  43.0    -3.2    690  3.5
 13000  -17.6   0.3   320   31   16   6.5   3.6    5.5  41.9    -3.8    649  3.3
 12500  -16.5   2.3   320   30   16   8.0   4.4    5.1  41.2    -4.2    601  3.1
 12000  -15.3   4.5   325   29   15   8.0   4.4    4.8  40.7    -4.5    551  2.8
 11500  -14.1   6.6   325   28   15   8.1   4.5    4.6  40.2    -4.8    500  2.5
 11000  -12.9   8.8   330   28   14   8.1   4.4    4.3  39.8    -5.1    449  2.3
 10500  -11.7  10.9   330   27   14   8.0   4.4    4.0  39.2    -5.4    398  2.0
 10250  -11.1  12.0   335   26   13   8.2   4.5    3.9  39.0    -5.5    373  1.9
 10000  -10.6  12.9   335   26   13   4.8   2.6    3.7  38.6    -5.7    350  1.8
  9750  -10.2  13.6   335   25   13   6.8   3.7    3.3  37.9    -6.2    333  1.7
  9500   -9.5  14.9   335   24   13  11.2   6.2    3.3  37.9    -6.2    303  1.5
  9250   -8.7  16.3   335   24   12   9.4   5.2    3.3  38.0    -6.2    273  1.4
  9000   -8.1  17.4   335   23   12   7.3   4.0    3.2  37.8    -6.3    246  1.3
  8750   -7.6  18.3   335   23   12   8.1   4.4    3.0  37.5    -6.5    223  1.1
  8500   -6.9  19.6   335   22   11  10.2   5.6    3.0  37.4    -6.5    194  1.0
  8250   -6.2  20.8   335   21   11   8.4   4.6    3.0  37.4    -6.6    166  0.8
  8000   -5.6  21.9   335   21   11   7.1   3.9    2.8  37.1    -6.8    142  0.7
  7750   -5.1  22.8   335   20   10   7.9   4.3    2.6  36.8    -7.0    118  0.6
  7500   -4.5  23.9   335   20   10   7.5   4.1    2.5  36.5    -7.2     93  0.5
  7250   -4.0  24.8   335   19   10   6.5   3.5    2.3  36.1    -7.4     71  0.4
  7000   -3.6  25.5   340   18    9   5.7   3.2    2.0  35.6    -7.7     51  0.3
  6750   -3.1  26.4   340   17    9   7.5   4.1    1.7  35.1    -8.0     30  0.2
  6500   -2.6  27.3   340   15    8   6.1   3.4    1.6  34.8    -8.2      6  0.0
  6250   -2.3  27.9   340   12    6   3.8   2.1    1.1  34.1    -8.7      M    M
  6000   -2.0  28.4   340    9    5   3.6   2.0    0.7  33.3    -9.2      M    M
  5750   -1.7  28.9   340    6    3   6.8   3.7    0.3  32.6    -9.7      M    M
  5500   -0.9  30.4   340    4    2  14.5   7.9    0.4  32.7    -9.6      M    M

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

           11/18/2017 at 0800 MST          |       11/18/2017 at 1100 MST
                                           |
K index... -23.8  LI... +10.7              | K index... -18.9  LI... +8.6
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -60.4 -76.7  285  68 35   3.4   1.9 | -59.6 -75.3  290  66 34   3.4   1.9
 45000 -55.2 -67.4  285  74 38   3.4   1.8 | -54.4 -65.9  285  73 37   3.7   2.0
 40000 -51.4 -60.5  285  72 37   2.5   1.4 | -53.0 -63.4  290  63 32   0.7   0.4
 38000 -50.7 -59.3  290  71 37  -2.1  -1.1 | -53.0 -63.4  295  60 31  -0.8  -0.4
 36000 -52.2 -62.0  295  70 36  -2.1  -1.2 | -53.4 -64.1  295  58 30  -0.8  -0.4
 34000 -53.2 -63.8  305  69 36   3.4   1.9 | -53.8 -64.8  300  58 30   2.4   1.3
 32000 -50.2 -58.4  310  69 35   5.1   2.8 | -51.0 -59.8  300  56 29   4.7   2.6
 30000 -47.0 -52.6  315  68 35   7.0   3.8 | -48.1 -54.6  300  55 28   6.9   3.8
 29000 -44.9 -48.8  320  67 34   7.1   3.9 | -45.2 -49.4  305  54 28   7.7   4.2
 28000 -42.7 -44.9  320  65 34   7.1   3.9 | -42.9 -45.2  305  54 28   7.7   4.2
 27000 -40.6 -41.1  325  64 33   7.1   3.9 | -40.5 -40.9  305  53 27   7.7   4.2
 26000 -38.4 -37.1  325  62 32   7.2   4.0 | -38.3 -36.9  305  51 26   7.5   4.1
 25000 -36.2 -33.2  330  60 31   7.2   4.0 | -36.1 -33.0  310  48 25   7.5   4.1
 24000 -34.1 -29.4  330  59 30   7.2   4.0 | -33.8 -28.8  310  46 24   7.5   4.1
 23000 -31.9 -25.4  330  56 29   7.3   4.0 | -31.6 -24.9  315  45 23   7.4   4.1
 22000 -29.7 -21.5  335  54 28   7.3   4.0 | -29.4 -20.9  315  44 22   7.4   4.1
 21000 -27.5 -17.5  335  51 26   7.3   4.0 | -27.2 -17.0  315  42 22   7.3   4.0
 20000 -25.3 -13.5  340  47 24   7.2   3.9 | -25.0 -13.0  315  40 21   7.2   3.9
 19500 -24.2 -11.6  340  45 23   7.2   3.9 | -23.9 -11.0  315  39 20   7.2   3.9
 19000 -23.2  -9.8  340  42 22   7.2   3.9 | -22.9  -9.2  315  38 20   7.2   4.0
 18500 -22.1  -7.8  340  40 21   7.2   3.9 | -21.8  -7.2  315  37 19   7.5   4.1
 18000 -20.6  -5.1  340  40 21   6.7   3.7 | -20.6  -5.1  315  36 18   8.1   4.4
 17500 -19.5  -3.1  340  41 21   6.8   3.7 | -19.4  -2.9  315  34 18   8.2   4.5
 17000 -18.5  -1.3  345  41 21   6.8   3.7 | -18.2  -0.8  315  33 17   7.1   3.9
 16500 -17.5   0.5  345  41 21   6.9   3.8 | -17.2   1.0  315  31 16   7.2   4.0
 16000 -16.5   2.3  345  41 21   6.1   3.3 | -16.0   3.2  320  30 16   8.2   4.5
 15500 -15.6   3.9  345  40 21   6.1   3.4 | -14.1   6.6  325  32 17   8.8   4.8
 15000 -14.8   5.4  345  40 20   4.8   2.6 | -13.0   8.6  325  33 17   6.1   3.4
 14500 -14.1   6.6  340  40 21   4.3   2.3 | -12.1  10.2  330  33 17   6.3   3.4
 14000 -13.5   7.7  340  40 21   3.4   1.8 | -11.2  11.8  330  32 17   5.2   2.9
 13500 -13.1   8.4  340  38 20   2.6   1.4 | -10.4  13.3  335  31 16   5.1   2.8
 13000 -12.7   9.1  340  36 19   1.9   1.1 |  -9.7  14.5  335  31 16   3.9   2.1
 12500 -12.5   9.5  340  32 17   1.2   0.7 |  -9.2  15.4  335  28 14   3.5   1.9
 12000 -12.4   9.7  340  28 14   1.4   0.8 |  -8.7  16.3  330  25 13   2.2   1.2
 11500 -12.2  10.0  340  24 12   1.8   1.0 |  -8.5  16.7  325  22 11   1.7   0.9
 11000 -11.9  10.6  340  20 10   4.0   2.2 |  -8.3  17.1  320  18  9   0.9   0.5
 10500 -11.1  12.0  335  18  9   5.7   3.1 |  -8.2  17.2  310  14  7   0.8   0.4
 10250 -10.7  12.7  335  17  8   5.0   2.7 |  -8.2  17.2  300  12  6   0.3   0.1
 10000 -10.4  13.3  335  16  8   2.2   1.2 |  -8.2  17.2  295  12  6   1.6   0.9
  9750 -10.2  13.6  335  16  8   6.5   3.5 |  -7.9  17.8  295  11  5   6.2   3.4
  9500  -9.4  15.1  330  16  8  11.4   6.3 |  -7.3  18.9  290   9  5   8.3   4.6
  9250  -8.7  16.3  325  17  9   7.8   4.3 |  -6.7  19.9  285   8  4   7.2   3.9
  9000  -8.3  17.1  320  18  9   3.9   2.2 |  -6.3  20.7  295   9  5   6.1   3.3
  8750  -7.9  17.8  315  18  9   6.0   3.3 |  -5.7  21.7  300  11  6   9.7   5.3
  8500  -7.4  18.7  315  18  9   8.1   4.4 |  -4.9  23.2  305  14  7  10.6   5.8
  8250  -6.8  19.8  310  18  9   7.2   4.0 |  -4.3  24.3  305  15  8   3.6   2.0
  8000  -6.3  20.7  310  17  9   6.9   3.8 |  -4.3  24.3  300  13  7   1.2   0.6
  7750  -5.8  21.6  305  16  8   7.8   4.3 |  -4.2  24.4  295  12  6   0.7   0.4
  7500  -5.1  22.8  305  14  7   8.8   4.8 |  -4.1  24.6  285   8  4   5.8   3.2
  7250  -4.5  23.9  305  13  7   8.7   4.8 |  -3.3  26.1  285   8  4  11.2   6.1
  7000  -3.9  25.0  305  12  6   8.7   4.8 |  -2.6  27.3  285   7  4  10.3   5.6
  6750  -3.2  26.2  305  11  6   8.9   4.9 |  -1.8  28.8  285   7  3   9.6   5.3
  6500  -2.6  27.3  305  10  5   8.2   4.5 |  -1.1  30.0  285   6  3   9.7   5.3
  6250  -2.0  28.4  300   9  5   7.5   4.1 |  -0.3  31.5  285   6  3  10.9   6.0
  6000  -1.4  29.5  290   8  4   7.9   4.3 |   0.5  32.9  285   6  3  10.4   5.7
  5750  -0.9  30.4  280   7  4   8.8   4.9 |   1.3  34.3  285   6  3  13.9   7.6
  5500  -0.2  31.6  270   5  3   9.9   5.4 |   2.6  36.7  285   5  3  19.8  10.9

           11/18/2017 at 1400 MST          |       11/18/2017 at 1700 MST
                                           |
K index... -11.4  LI... +7.0               | K index... -4.9  LI... +6.0
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -59.9 -75.8  295  63 32   3.6   2.0 | -60.5 -76.9  295  63 33   2.9   1.6
 45000 -54.5 -66.1  290  71 37   3.9   2.1 | -56.2 -69.2  295  75 39   3.2   1.7
 40000 -54.3 -65.7  295  64 33   0.0   0.0 | -56.7 -70.1  305  67 35  -0.5  -0.3
 38000 -54.2 -65.6  300  61 32   0.1   0.0 | -56.2 -69.2  310  68 35   2.2   1.2
 36000 -54.2 -65.6  305  61 31   0.1   0.0 | -54.9 -66.8  315  73 37   2.2   1.2
 34000 -54.0 -65.2  310  61 31   3.9   2.1 | -53.4 -64.1  325  78 40   5.8   3.2
 32000 -50.8 -59.4  315  62 32   5.4   3.0 | -50.0 -58.0  320  76 39   5.8   3.2
 30000 -47.5 -53.5  320  64 33   7.1   3.9 | -46.4 -51.5  320  73 38   7.2   4.0
 29000 -44.7 -48.5  320  62 32   7.4   4.0 | -44.3 -47.7  320  71 37   7.0   3.9
 28000 -42.5 -44.5  320  62 32   7.4   4.0 | -41.7 -43.1  320  68 35   7.1   3.9
 27000 -40.3 -40.5  320  61 31   7.3   4.0 | -39.5 -39.1  320  66 34   7.4   4.1
 26000 -38.2 -36.8  320  58 30   7.0   3.9 | -37.2 -35.0  320  64 33   7.8   4.3
 25000 -36.1 -33.0  315  55 28   7.0   3.9 | -34.9 -30.8  320  62 32   7.8   4.3
 24000 -34.0 -29.2  315  52 27   7.1   3.9 | -32.6 -26.7  320  60 31   7.6   4.1
 23000 -31.7 -25.1  315  50 26   7.7   4.2 | -30.5 -22.9  320  58 30   7.0   3.9
 22000 -29.4 -20.9  315  48 25   7.7   4.2 | -28.4 -19.1  320  56 29   7.0   3.9
 21000 -27.2 -17.0  315  46 24   7.9   4.3 | -26.3 -15.3  320  53 27   7.0   3.8
 20000 -24.8 -12.6  315  44 23   8.0   4.4 | -24.2 -11.6  320  50 26   7.0   3.8
 19500 -23.6 -10.5  315  44 23   8.0   4.4 | -23.2  -9.8  320  49 25   7.0   3.8
 19000 -22.4  -8.3  315  43 22   8.0   4.4 | -22.1  -7.8  320  48 24   7.0   3.8
 18500 -21.2  -6.2  315  42 22   7.7   4.2 | -21.1  -6.0  320  46 24   7.1   3.9
 18000 -20.1  -4.2  315  42 21   7.5   4.1 | -20.0  -4.0  320  45 23   7.2   4.0
 17500 -19.0  -2.2  315  41 21   7.5   4.1 | -18.9  -2.0  320  43 22   7.2   4.0
 17000 -17.9  -0.2  315  40 21   7.5   4.1 | -17.9  -0.2  320  42 22   6.9   3.8
 16500 -16.7   1.9  315  39 20   7.5   4.1 | -16.9   1.6  320  41 21   6.9   3.8
 16000 -15.6   3.9  315  38 19   8.0   4.4 | -15.8   3.6  320  40 21   7.4   4.1
 15500 -14.4   6.1  315  36 19   8.0   4.4 | -14.7   5.5  320  39 20   7.5   4.1
 15000 -12.6   9.3  310  34 17   6.9   3.8 | -13.0   8.6  320  37 19   8.1   4.4
 14500 -11.6  11.1  310  32 16   7.1   3.9 | -11.8  10.8  320  35 18   8.1   4.5
 14000 -10.5  13.1  310  30 15   7.0   3.8 | -10.7  12.7  320  33 17   6.7   3.7
 13500  -9.5  14.9  310  28 15   7.1   3.9 |  -9.7  14.5  320  31 16   6.8   3.7
 13000  -8.6  16.5  310  27 14   4.6   2.6 |  -8.7  16.3  320  29 15   6.0   3.3
 12500  -8.0  17.6  310  25 13   4.0   2.2 |  -7.8  18.0  320  26 14   6.0   3.3
 12000  -7.4  18.7  310  23 12   4.0   2.2 |  -6.9  19.6  315  24 12   5.7   3.2
 11500  -6.8  19.8  305  21 11   3.9   2.2 |  -6.1  21.0  315  21 11   5.7   3.1
 11000  -6.2  20.8  305  19 10   4.9   2.7 |  -5.2  22.6  310  19 10   6.4   3.5
 10500  -5.4  22.3  300  18  9   5.6   3.1 |  -4.2  24.4  305  17  9   7.2   3.9
 10250  -5.0  23.0  300  18  9   3.4   1.8 |  -3.7  25.3  305  16  8   3.6   2.0
 10000  -4.8  23.4  300  17  9   3.3   1.8 |  -3.6  25.5  305  16  8   4.0   2.2
  9750  -4.4  24.1  300  17  9   7.1   3.9 |  -3.0  26.6  305  17  9   9.3   5.1
  9500  -3.9  25.0  300  18  9   9.0   4.9 |  -2.3  27.9  300  17  9  10.1   5.5
  9250  -3.3  26.1  300  18  9   5.1   2.8 |  -1.7  28.9  300  18  9   6.2   3.4
  9000  -3.1  26.4  300  18  9   1.1   0.6 |  -1.4  29.5  300  18  9   2.9   1.6
  8750  -3.0  26.6  300  17  9   2.3   1.3 |  -1.1  30.0  295  18  9   4.9   2.7
  8500  -2.8  27.0  300  15  8   2.5   1.4 |  -0.7  30.7  295  17  9   4.9   2.7
  8250  -2.6  27.3  295  12  6   3.2   1.7 |  -0.4  31.3  290  16  8   3.9   2.1
  8000  -2.4  27.7  295   9  4   2.9   1.6 |  -0.2  31.6  285  14  7   3.7   2.0
  7750  -2.2  28.0  285   5  3   6.0   3.3 |   0.1  32.2  280  12  6   3.2   1.8
  7500  -1.5  29.3  280   3  2   9.7   5.3 |   0.3  32.5  275  10  5   4.5   2.5
  7250  -0.8  30.6  275   3  1   9.5   5.2 |   0.8  33.4  265   8  4   6.1   3.3
  7000  -0.1  31.8  275   2  1   9.5   5.2 |   1.2  34.2  250   7  3   5.6   3.1
  6750   0.6  33.1  275   2  1  10.1   5.5 |   1.6  34.9  230   6  3   6.2   3.4
  6500   1.4  34.5  275   2  1  10.4   5.7 |   2.1  35.8  220   6  3   8.1   4.4
  6250   2.2  36.0  275   2  1  10.2   5.6 |   2.8  37.0  210   5  3   9.2   5.0
  6000   2.9  37.2  275   2  1   9.9   5.4 |   3.4  38.1  200   5  3   8.3   4.6
  5750   3.7  38.7  275   2  1  12.9   7.1 |   4.0  39.2  190   5  2   6.7   3.7
  5500   4.9  40.8  275   2  1  19.0  10.4 |   4.4  39.9  180   4  2   5.4   2.9
________________________________________________________________________________

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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