Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 050011
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1711 MST Thursday, February 4, 2016

This forecast is for Friday, February 5, 2016:

If the trigger temperature of 36.2 F/2.4 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 246 ft/min (1.2 m/s)
   Maximum height of thermals.................. 8992 ft MSL (3685 ft AGL)

Forecast maximum temperature................... 36.0 F/2.7 C
Time of trigger temperature.................... 1330 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................. 6294 ft MSL (987 ft AGL)
Thermal soaring outlook for Saturday 02/06..... Fair

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 PVA
Potential height of wave....................... 15625 ft MSL (10318 ft AGL)
Wave soaring outlook for Saturday 02/06........ Fair

Remarks... None

Sunrise/Sunset.................... 07:03:45 / 17:22:12 MST
Total possible sunshine........... 10 hr 18 min 27 sec (618 min 27 sec)
Altitude of sun at 12:13:20 MST... 34.36 degrees

Upper air data from numerical model forecast valid on 02/05/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 12804 ft MSL (7497 ft AGL)
Lifted condensation level....... 12138 ft MSL (6832 ft AGL)
Lifted index.................... +5.6
K index......................... +9.3

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  -53.4 -64.1   290   19   10   0.7   0.4      M     M       M      M    M
 45000  -52.3 -62.1   300   21   11   0.7   0.4      M     M       M      M    M
 40000  -49.9 -57.8   315   37   19   1.7   0.9      M     M       M      M    M
 38000  -48.9 -56.0   315   42   22   1.3   0.7      M     M       M      M    M
 36000  -48.1 -54.6   315   35   18   1.3   0.7      M     M       M      M    M
 34000  -47.3 -53.1   310   28   14   1.3   0.7      M     M       M      M    M
 32000  -47.5 -53.5   310   26   13  -1.1  -0.6      M     M       M      M    M
 30000  -48.2 -54.8   310   26   13  -1.1  -0.6      M     M       M      M    M
 29000  -48.3 -54.9   305   24   12   0.6   0.4   26.2  79.1    18.0      M    M
 28000  -48.1 -54.6   295   21   11   0.7   0.4   22.5  72.4    15.4      M    M
 27000  -47.9 -54.2   280   20   10   0.6   0.3   19.0  66.2    12.9      M    M
 26000  -47.3 -53.1   270   19   10   6.9   3.8   16.1  61.0    10.8      M    M
 25000  -45.4 -49.7   265   19   10   6.5   3.5   14.7  58.5     9.9      M    M
 24000  -43.5 -46.3   260   19   10   6.5   3.5   13.5  56.4     9.1      M    M
 23000  -41.5 -42.7   255   19   10   7.0   3.8   12.4  54.4     8.3      M    M
 22000  -39.4 -38.9   260   18    9   6.9   3.8   11.3  52.4     7.4      M    M
 21000  -37.4 -35.3   270   17    9   6.9   3.8   10.3  50.6     6.7      M    M
 20000  -35.2 -31.4   285   15    8   7.4   4.1    9.4  49.0     6.0      M    M
 19500  -34.1 -29.4   295   15    8   7.5   4.1    9.0  48.2     5.7      M    M
 19000  -33.0 -27.4   305   16    8   7.5   4.1    8.6  47.5     5.4      M    M
 18500  -31.9 -25.4   320   17    9   7.5   4.1    8.2  46.8     5.1      M    M
 18000  -30.8 -23.4   330   18    9   6.6   3.6    7.8  46.1     4.8      M    M
 17500  -29.8 -21.6   340   19   10   6.4   3.5    7.2  45.0     4.3      M    M
 17000  -28.9 -20.0   350   21   11   7.2   4.0    6.6  43.9     3.8      M    M
 16500  -27.6 -17.7   345   22   11   9.0   4.9    6.4  43.6     3.6      M    M
 16000  -26.3 -15.3   345   23   12   9.6   4.9    6.3  43.4     3.5      M    M
 15500  -24.5 -12.1   350   23   12   7.8   4.3    5.9  42.6     3.2      M    M
 15000  -23.3  -9.9   350   24   12   8.0   4.4    5.6  42.0     2.9      M    M
 14500  -22.1  -7.8   355   24   12   8.2   4.5    5.3  41.5     2.7      M    M
 14000  -20.9  -5.6   355   23   12   7.9   4.4    5.0  41.1     2.4      M    M
 13500  -19.8  -3.6   355   24   12   7.5   4.1    4.7  40.4     2.1      M    M
 13000  -18.7  -1.7   355   24   12   7.6   4.2    4.3  39.8     1.7      M    M
 12500  -17.5   0.5   355   24   12   7.7   4.2    4.0  39.1     1.4      M    M
 12000  -16.4   2.5   360   24   12   7.8   4.3    3.6  38.6     1.1      M    M
 11500  -15.2   4.6   360   24   13   8.0   4.4    3.3  38.0     0.8      M    M
 11000  -14.0   6.8   360   24   13   8.6   4.7    3.1  37.5     0.6      M    M
 10500  -12.7   9.1   360   25   13   9.4   5.1    3.0  37.3     0.5      M    M
 10250  -12.0  10.4   360   25   13   8.5   4.7    2.9  37.3     0.4      M    M
 10000  -11.5  11.3   360   25   13   4.0   2.2    2.7  36.8     0.2      M    M
  9750  -11.2  11.8   355   25   13   7.9   4.3    2.2  36.0    -0.2    339  1.7
  9500  -10.2  13.6   355   24   12  14.0   7.7    2.4  36.4    -0.0    304  1.5
  9250   -9.3  15.3   355   23   12   9.9   5.4    2.6  36.8     0.2      M    M
  9000   -8.8  16.2   355   22   11   5.3   2.9    2.5  36.4     0.0      M    M
  8750   -8.4  16.9   355   21   11   6.9   3.8    2.1  35.8    -0.3    226  1.1
  8500   -7.7  18.1   350   19   10   9.1   5.0    2.0  35.7    -0.4    199  1.0
  8250   -7.1  19.2   345   18    9   7.6   4.2    1.9  35.5    -0.5    173  0.9
  8000   -6.6  20.1   345   17    9   7.0   3.8    1.7  35.1    -0.7    150  0.8
  7750   -6.0  21.2   345   17    9   7.4   4.1    1.5  34.7    -0.9    126  0.6
  7500   -5.5  22.1   340   17    9   6.2   3.4    1.3  34.4    -1.1    103  0.5
  7250   -5.1  22.8   335   17    9   4.7   2.6    1.0  33.7    -1.5     84  0.4
  7000   -4.8  23.4   330   18    9   4.6   2.5    0.6  33.0    -1.9     66  0.3
  6750   -4.4  24.1   325   18    9   4.6   2.5    0.2  32.4    -2.2     49  0.2
  6500   -4.1  24.6   320   19   10   4.7   2.6   -0.2  31.7    -2.6     31  0.2
  6250   -3.7  25.3   315   17    9   5.5   3.0   -0.6  31.0    -3.0     13  0.1
  6000   -3.3  26.1   310   16    8   3.5   1.9   -0.9  30.4    -3.4      M    M
  5750   -3.3  26.1   305   14    7  -0.9  -0.5   -1.6  29.2    -4.0      M    M
  5500   -3.5  25.7   300    9    5  -2.1  -1.1   -2.4  27.6    -5.0      M    M

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

           02/05/2016 at 0800 MST          |       02/05/2016 at 1100 MST
                                           |
K index... +10.6  LI... +1.0               | K index... +5.8  LI... +4.7
CAPE... 0.0  CIN... -0.2                   | CAPE... 0.0  CIN... -0.9
                                           |
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 -53.6 -64.5  305  18  9   0.8   0.4 | -53.8 -64.8  300  19 10   0.4   0.2
 45000 -52.5 -62.5  310  20 10   0.8   0.4 | -53.1 -63.6  310  21 11   0.4   0.2
 40000 -49.5 -57.1  320  26 14   2.1   1.2 | -50.7 -59.3  320  25 13   1.8   1.0
 38000 -48.4 -55.1  325  29 15   0.3   0.1 | -49.8 -57.6  325  26 14  -0.8  -0.4
 36000 -48.1 -54.6  330  29 15   0.4   0.2 | -50.2 -58.4  345  32 17  -0.6  -0.3
 34000 -47.8 -54.0  335  29 15   0.4   0.2 | -50.5 -58.9  360  41 21  -0.6  -0.3
 32000 -48.0 -54.4  350  32 16  -0.6  -0.3 | -50.6 -59.1  005  51 26   0.2   0.1
 30000 -48.4 -55.1  360  37 19  -0.7  -0.4 | -50.5 -58.9  010  64 33  -0.3  -0.1
 29000 -48.2 -54.8  360  38 19   1.5   0.8 | -49.4 -56.9  015  66 34   4.5   2.4
 28000 -47.7 -53.9  360  37 19   1.5   0.8 | -48.1 -54.6  015  67 35   4.4   2.4
 27000 -47.2 -53.0  360  36 18   1.5   0.8 | -46.8 -52.2  015  69 35   4.5   2.4
 26000 -46.5 -51.7  360  34 18   5.1   2.8 | -45.2 -49.4  020  69 35   6.7   3.7
 25000 -45.1 -49.2  355  32 16   4.7   2.6 | -43.2 -45.8  020  67 34   6.6   3.6
 24000 -43.7 -46.7  350  29 15   4.7   2.6 | -41.3 -42.3  020  65 33   6.6   3.6
 23000 -42.2 -44.0  350  28 14   5.9   3.2 | -39.2 -38.6  020  62 32   6.9   3.8
 22000 -40.5 -40.9  350  29 15   5.7   3.2 | -37.2 -35.0  015  57 29   6.9   3.8
 21000 -38.8 -37.8  355  30 15   5.7   3.1 | -35.1 -31.2  015  52 27   6.9   3.8
 20000 -36.6 -33.9  355  29 15   8.2   4.5 | -32.9 -27.2  010  48 25   7.4   4.1
 19500 -35.4 -31.7  355  28 14   8.2   4.5 | -31.8 -25.2  010  46 24   7.4   4.1
 19000 -34.2 -29.6  355  27 14   8.2   4.5 | -30.7 -23.3  010  45 23   7.4   4.1
 18500 -32.9 -27.2  355  26 13   8.2   4.5 | -29.6 -21.3  010  43 22   7.6   4.2
 18000 -31.7 -25.1  350  26 13   8.4   4.6 | -28.6 -19.5  005  41 21   5.7   3.1
 17500 -30.4 -22.7  350  26 14   8.5   4.6 | -27.8 -18.0  005  39 20   5.7   3.1
 17000 -29.2 -20.6  350  27 14   8.4   4.6 | -26.9 -16.4  360  37 19   6.1   3.3
 16500 -27.9 -18.2  350  27 14   8.4   4.6 | -26.0 -14.8  360  36 18   6.3   3.5
 16000 -26.7 -16.1  345  27 14   8.5   4.7 | -24.6 -12.3  360  34 17   6.3   3.4
 15500 -24.7 -12.5  345  27 14   8.7   4.8 | -23.6 -10.5  355  33 17   6.2   3.4
 15000 -23.5 -10.3  345  27 14   8.5   4.7 | -22.7  -8.9  350  32 16   7.2   3.9
 14500 -22.2  -8.0  345  26 13   8.4   4.6 | -21.5  -6.7  350  30 16   7.6   4.2
 14000 -21.0  -5.8  340  26 13   8.4   4.6 | -20.4  -4.7  345  29 15   8.0   4.4
 13500 -19.7  -3.5  345  26 13   8.4   4.6 | -19.1  -2.4  345  29 15   8.3   4.5
 13000 -18.5  -1.3  345  26 14   8.0   4.4 | -17.9  -0.2  345  29 15   7.6   4.2
 12500 -17.3   0.9  345  27 14   7.5   4.1 | -16.9   1.6  345  28 15   7.0   3.8
 12000 -16.2   2.8  350  27 14   7.3   4.0 | -15.8   3.6  345  27 14   6.8   3.7
 11500 -15.2   4.6  355  27 14   7.1   3.9 | -14.9   5.2  345  26 13   6.7   3.7
 11000 -14.2   6.4  355  27 14   7.1   3.9 | -13.8   7.2  345  24 12   7.6   4.2
 10500 -13.1   8.4  360  28 14   7.2   4.0 | -12.7   9.1  350  23 12   8.1   4.5
 10250 -12.6   9.3  360  28 15   7.0   3.8 | -12.1  10.2  350  23 12   7.3   4.0
 10000 -12.1  10.2  360  29 15   6.1   3.3 | -11.6  11.1  350  22 12   5.6   3.1
  9750 -11.6  11.1  360  29 15   7.7   4.2 | -11.1  12.0  350  22 11   7.7   4.2
  9500 -10.9  12.4  360  30 15   9.5   5.2 | -10.4  13.3  355  22 12   9.9   5.5
  9250 -10.3  13.5  355  31 16   8.3   4.5 |  -9.8  14.4  355  23 12   8.1   4.5
  9000  -9.7  14.5  355  31 16   7.1   3.9 |  -9.2  15.4  355  23 12   6.5   3.6
  8750  -9.1  15.6  355  31 16   8.5   4.7 |  -8.7  16.3  355  23 12   8.3   4.6
  8500  -8.4  16.9  350  30 15   9.2   5.0 |  -8.0  17.6  355  23 12   9.2   5.1
  8250  -7.8  18.0  350  29 15   7.3   4.0 |  -7.4  18.7  355  22 12   8.0   4.4
  8000  -7.3  18.9  345  27 14   6.2   3.4 |  -6.8  19.8  355  21 11   7.1   3.9
  7750  -6.8  19.8  345  24 13   7.9   4.3 |  -6.3  20.7  355  20 10   9.2   5.1
  7500  -6.2  20.8  340  22 11   7.2   4.0 |  -5.5  22.1  350  18  9   8.6   4.7
  7250  -5.8  21.6  335  21 11   5.2   2.9 |  -5.0  23.0  345  16  8   6.1   3.3
  7000  -5.3  22.5  330  20 10   5.9   3.2 |  -4.5  23.9  335  15  8   6.7   3.7
  6750  -4.9  23.2  325  20 10   5.2   2.8 |  -4.0  24.8  330  13  7   6.8   3.8
  6500  -4.6  23.7  320  19 10   4.0   2.2 |  -3.5  25.7  320  12  6   5.7   3.1
  6250  -4.3  24.3  315  18  9   4.9   2.7 |  -3.2  26.2  310  12  6   4.9   2.7
  6000  -3.9  25.0  310  17  9   1.4   0.7 |  -2.8  27.0  305  12  6   4.0   2.2
  5750  -4.3  24.3  305  14  7 -10.2  -5.6 |  -2.7  27.1  295  10  5   2.4   1.3
  5500  -5.4  22.3  290   9  5 -18.6 -10.2 |  -2.5  27.5  285   7  4   3.9   2.1

           02/05/2016 at 1400 MST          |       02/05/2016 at 1700 MST
                                           |
K index... -6.1  LI... +6.1                | K index... -16.2  LI... +7.1
CAPE... 0.0  CIN... -1.2                   | 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 -53.6 -64.5  305  20 10   0.5   0.3 | -54.6 -66.3  310  23 12   0.2   0.1
 45000 -52.9 -63.2  315  22 12   0.5   0.3 | -54.3 -65.7  320  27 14   0.2   0.1
 40000 -51.5 -60.7  330  31 16   0.9   0.5 | -53.7 -64.7  340  39 20   0.4   0.2
 38000 -51.3 -60.3  335  36 18  -1.8  -1.0 | -53.7 -64.7  345  47 24  -2.2  -1.2
 36000 -52.3 -62.1  350  46 24  -1.7  -0.9 | -55.1 -67.2  355  62 32  -2.2  -1.2
 34000 -53.3 -63.9  360  58 30  -1.7  -0.9 | -56.4 -69.5  005  79 41  -3.0  -1.6
 32000 -52.5 -62.5  005  66 34   2.1   1.2 | -54.1 -65.4  005  87 45   4.8   2.6
 30000 -51.1 -60.0  005  75 39   3.1   1.7 | -50.8 -59.4  005  93 48   7.2   3.9
 29000 -49.4 -56.9  005  74 38   5.9   3.3 | -48.4 -55.1  005  89 46   7.9   4.3
 28000 -47.6 -53.7  005  73 38   5.9   3.3 | -46.0 -50.8  005  84 43   7.9   4.3
 27000 -45.9 -50.6  005  72 37   6.0   3.3 | -43.7 -46.7  010  80 41   7.9   4.3
 26000 -43.9 -47.0  010  70 36   7.2   3.9 | -41.2 -42.2  010  76 39   8.2   4.5
 25000 -41.7 -43.1  010  65 34   7.2   4.0 | -38.8 -37.8  005  72 37   8.2   4.5
 24000 -39.6 -39.3  010  61 31   7.3   4.0 | -36.3 -33.3  005  68 35   8.3   4.5
 23000 -37.3 -35.1  010  57 29   7.6   4.2 | -34.1 -29.4  005  63 32   6.8   3.7
 22000 -35.1 -31.2  010  54 28   7.6   4.2 | -32.1 -25.8  005  57 29   6.8   3.7
 21000 -32.8 -27.0  015  50 26   7.6   4.2 | -30.0 -22.0  005  52 27   6.8   3.7
 20000 -30.5 -22.9  015  47 24   7.9   4.3 | -28.1 -18.6  005  48 24   6.4   3.5
 19500 -29.3 -20.7  015  45 23   7.9   4.3 | -27.2 -17.0  005  45 23   6.4   3.5
 19000 -28.1 -18.6  015  44 22   7.9   4.3 | -26.2 -15.2  005  44 22   6.4   3.5
 18500 -26.9 -16.4  015  42 22   8.0   4.4 | -25.3 -13.5  360  42 21   6.5   3.5
 18000 -25.8 -14.4  010  40 21   6.3   3.5 | -24.2 -11.6  360  39 20   7.4   4.1
 17500 -24.9 -12.8  010  38 20   6.5   3.6 | -23.1  -9.6  360  37 19   7.3   4.0
 17000 -23.9 -11.0  005  36 19   5.8   3.2 | -22.0  -7.6  360  35 18   8.0   4.4
 16500 -23.1  -9.6  005  35 18   5.5   3.0 | -20.8  -5.4  355  33 17   8.0   4.4
 16000 -21.9  -7.4  360  32 17   5.3   2.9 | -19.2  -2.6  355  31 16   5.3   2.9
 15500 -21.1  -6.0  355  31 16   5.3   2.9 | -18.3  -0.9  350  30 15   5.7   3.1
 15000 -20.3  -4.5  350  30 16   5.1   2.8 | -17.5   0.5  350  28 15   4.7   2.6
 14500 -19.6  -3.3  350  29 15   5.0   2.8 | -16.8   1.8  350  27 14   4.5   2.5
 14000 -18.8  -1.8  345  28 15   6.0   3.3 | -16.1   3.0  345  26 13   5.3   2.9
 13500 -17.8  -0.0  345  27 14   6.6   3.6 | -15.3   4.5  340  25 13   5.5   3.0
 13000 -16.8   1.8  345  26 14   7.4   4.1 | -14.4   6.1  340  23 12   5.9   3.2
 12500 -15.6   3.9  345  26 14   8.0   4.4 | -13.5   7.7  335  22 11   6.1   3.3
 12000 -14.4   6.1  345  26 13   7.4   4.0 | -12.6   9.3  335  21 11   6.0   3.3
 11500 -13.4   7.9  345  26 14   7.0   3.8 | -11.8  10.8  335  19 10   5.9   3.2
 11000 -12.3   9.9  345  26 14   7.8   4.3 | -10.8  12.6  335  17  9   7.0   3.8
 10500 -11.1  12.0  345  25 13   8.5   4.7 |  -9.8  14.4  335  15  8   7.7   4.2
 10250 -10.5  13.1  345  24 13   6.7   3.7 |  -9.2  15.4  335  14  7   5.6   3.1
 10000 -10.1  13.8  345  24 12   3.9   2.2 |  -8.9  16.0  330  13  7   4.0   2.2
  9750  -9.8  14.4  345  23 12   7.2   3.9 |  -8.5  16.7  330  13  7   9.2   5.0
  9500  -9.1  15.6  345  21 11  10.1   5.5 |  -7.6  18.3  320  12  6  12.8   7.0
  9250  -8.4  16.9  340  19 10   8.1   4.5 |  -6.8  19.8  315  12  6   8.8   4.8
  9000  -7.9  17.8  340  17  9   6.6   3.6 |  -6.3  20.7  310  14  7   5.4   3.0
  8750  -7.3  18.9  335  15  8   8.7   4.7 |  -5.8  21.6  305  16  8   8.6   4.7
  8500  -6.6  20.1  325  14  7   9.7   5.3 |  -5.1  22.8  300  20 10   8.9   4.9
  8250  -6.0  21.2  315  13  7   8.1   4.4 |  -4.6  23.7  300  22 11   5.6   3.1
  8000  -5.4  22.3  310  14  7   7.6   4.2 |  -4.3  24.3  300  22 11   3.8   2.1
  7750  -4.8  23.4  305  14  7   8.1   4.5 |  -4.0  24.8  295  22 11   7.2   3.9
  7500  -4.3  24.3  300  15  7   7.8   4.3 |  -3.3  26.1  295  21 11   9.0   4.9
  7250  -3.7  25.3  300  14  7   7.0   3.9 |  -2.7  27.1  295  20 10   7.3   4.0
  7000  -3.2  26.2  300  13  7   7.4   4.1 |  -2.2  28.0  295  18  9   7.8   4.3
  6750  -2.7  27.1  295  12  6   6.6   3.6 |  -1.6  29.1  295  16  8   7.5   4.1
  6500  -2.3  27.9  295  11  5   5.5   3.0 |  -1.1  30.0  290  14  7   5.1   2.8
  6250  -1.9  28.6  290   8  4   5.1   2.8 |  -0.8  30.6  285  12  6   3.4   1.9
  6000  -1.5  29.3  285   7  3   6.0   3.3 |  -0.6  30.9  275  10  5   3.7   2.0
  5750  -1.1  30.0  270   5  2   7.3   4.0 |  -0.5  31.1  255   8  4  -2.8  -1.5
  5500  -0.6  30.9  250   3  2   7.3   4.0 |  -1.2  29.8  235   6  3 -12.7  -6.9
________________________________________________________________________________

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.

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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