Soaring Guidance
Issued by NWS Denver/Boulder, CO

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
393
UXUS97 KBOU 051328
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0628 MST Friday, February 5, 2016

This forecast is for Friday, February 5, 2016:

If the trigger temperature of 34.7 F/1.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 628 ft/min (3.2 m/s)
   Maximum height of thermals.................. 12670 ft MSL (7385 ft AGL)

Forecast maximum temperature................... 38.0 F/3.8 C
Time of trigger temperature.................... 1215 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................. 5780 ft MSL (494 ft AGL)
Thermal soaring outlook for Saturday 02/06..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 18071 ft MSL (12786 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 rawinsonde observation taken on 02/05/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 12631 ft MSL (7346 ft AGL)
Lifted condensation level....... 12695 ft MSL (7409 ft AGL)
Lifted index.................... +4.0
K index......................... +12.2

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  -53.8 -64.8   295   33   17   4.9   2.7  114.1 237.4    62.7      M    M
 45000  -52.1 -61.8   300   37   19   2.2   1.2   92.3 198.1    53.8      M    M
 40000  -48.9 -56.0   300   30   15   2.4   1.3   72.8 163.1    45.0      M    M
 38000  -48.0 -54.4   300   25   13   4.5   2.5   65.3 149.5    41.2      M    M
 36000  -46.9 -52.4   300   38   19  -1.4  -0.7   58.2 136.8    37.5      M    M
 34000  -48.3 -54.9   295   31   16   2.9   1.6   47.7 117.8    31.1      M    M
 32000  -47.1 -52.8   305   27   14  -3.7  -2.0   41.1 106.0    27.2      M    M
 30000  -47.7 -53.9   310   21   11   3.6   2.0   32.2  90.0    21.3      M    M
 29000  -48.5 -55.3   315   23   12   2.7   1.5   26.3  79.3    17.2      M    M
 28000  -47.8 -54.0   290   18    9  -0.8  -0.4   23.4  74.0    15.2      M    M
 27000  -48.8 -55.8   260   19   10  -5.4  -2.9   18.2  64.8    11.5      M    M
 26000  -48.8 -55.8   235   24   12   4.7   2.6   14.6  58.2     8.7      M    M
 25000  -46.1 -51.0   225   20   10  10.2   5.6   14.2  57.6     8.6      M    M
 24000  -44.7 -48.5   205   20   10   7.8   4.3   12.3  54.1     7.2      M    M
 23000  -42.4 -44.3   220   17    8   8.3   4.5   11.6  52.9     6.7      M    M
 22000  -39.9 -39.8   235   10    5   6.2   3.4   11.1  51.9     6.3      M    M
 21000  -38.7 -37.7   285    5    3   5.5   3.0    9.0  48.2     4.7      M    M
 20000  -36.6 -33.9   340   15    7   7.1   3.9    8.0  46.5     3.9      M    M
 19500  -35.5 -31.9   345   18    9   7.1   3.9    7.5  45.6     3.5      M    M
 19000  -34.5 -30.1   350   22   11   7.2   3.9    7.1  44.7     3.1      M    M
 18500  -33.4 -28.1   355   26   13   7.8   4.3    6.6  43.9     2.8      M    M
 18000  -32.1 -25.8   355   29   15   9.0   4.9    6.5  43.6     2.6      M    M
 17500  -30.8 -23.4   355   28   14   9.1   5.0    6.3  43.4     2.5      M    M
 17000  -29.4 -20.9   360   27   14   9.1   5.0    6.2  43.1     2.4      M    M
 16500  -28.0 -18.4   360   26   13   9.1   5.0    6.1  43.0     2.3      M    M
 16000  -26.7 -16.1   005   25   13   9.1   5.0    6.0  42.8     2.3      M    M
 15500  -25.3 -13.5   005   25   13   9.2   5.0    5.9  42.6     2.2      M    M
 15000  -24.0 -11.2   010   25   13   7.8   4.3    5.7  42.3     2.0      M    M
 14500  -22.4  -8.3   015   25   13   7.5   4.1    5.1  41.2     1.5      M    M
 14000  -21.3  -6.3   015   25   13   7.0   3.9    4.7  40.5     1.1      M    M
 13500  -20.3  -4.5   010   26   13   6.9   3.8    4.2  39.6     0.6      M    M
 13000  -19.2  -2.6   005   27   14   6.9   3.8    3.7  38.7     0.2      M    M
 12500  -18.2  -0.8   360   28   14   6.9   3.8    3.3  37.9    -0.2    605  3.1
 12000  -17.2   1.0   355   29   15   6.9   3.8    2.9  37.2    -0.6    559  2.8
 11500  -16.2   2.8   355   30   15   7.4   4.0    2.4  36.3    -1.1    514  2.6
 11000  -15.0   5.0   350   31   16   8.1   4.4    2.1  35.8    -1.4    464  2.4
 10500  -13.8   7.2   350   31   16   8.3   4.5    1.8  35.3    -1.6    413  2.1
 10250  -13.1   8.4   350   32   16   9.0   5.0    1.7  35.1    -1.7    386  2.0
 10000  -12.4   9.7   345   33   17   9.5   5.2    1.7  35.1    -1.8    358  1.8
  9750  -11.7  10.9   345   32   16   9.6   5.3    1.7  35.1    -1.8    329  1.7
  9500  -11.0  12.2   345   30   16   9.6   5.3    1.7  35.1    -1.8    300  1.5
  9250  -10.3  13.5   345   29   15   9.6   5.3    1.7  35.1    -1.8    271  1.4
  9000   -9.6  14.7   345   28   14   9.6   5.3    1.7  35.1    -1.8    242  1.2
  8750   -8.9  16.0   345   27   14   9.6   5.3    1.7  35.1    -1.8    213  1.1
  8500   -8.1  17.4   345   26   14   9.6   5.3    1.7  35.0    -1.8    184  0.9
  8250   -7.4  18.7   345   26   13   9.6   5.3    1.7  35.0    -1.8    155  0.8
  8000   -6.7  19.9   345   25   13   9.6   5.3    1.7  35.0    -1.8    126  0.6
  7750   -6.0  21.2   345   23   12   9.6   5.3    1.6  35.0    -1.9     97  0.5
  7500   -5.3  22.5   345   22   11   9.6   5.3    1.6  34.9    -1.9     68  0.3
  7250   -4.5  23.9   345   21   11   9.6   5.3    1.6  34.9    -1.9     39  0.2
  7000   -3.8  25.2   345   19   10   9.6   5.3    1.6  34.9    -1.9     11  0.1
  6750   -3.1  26.4   350   17    9   9.7   5.3    1.6  34.8    -2.0      M    M
  6500   -2.4  27.7   355   15    8   9.2   5.0    1.5  34.8    -2.0      M    M
  6250   -1.7  28.9   360   13    7  11.1   6.1    1.5  34.7    -2.0      M    M
  6000   -1.0  30.2   010   11    6   3.9   2.2    1.5  34.7    -2.1      M    M
  5750   -1.2  29.8   020    7    3  -6.7  -3.7    0.5  33.0    -3.0      M    M
  5500   -1.9  28.6   055    3    1 -13.7  -7.5   -0.9  30.4    -4.5      M    M

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

           02/05/2016 at 0800 MST          |       02/05/2016 at 1100 MST
                                           |
K index... +8.6  LI... +0.8                | K index... +2.2  LI... +3.6
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -1.1
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -53.3 -63.9  290  21 11   1.2   0.6 | -53.6 -64.5  300  18  9   0.6   0.4
 45000 -51.5 -60.7  295  26 13   1.2   0.6 | -52.6 -62.7  310  20 10   0.7   0.4
 40000 -49.9 -57.8  315  23 12   1.1   0.6 | -50.6 -59.1  330  26 14   1.4   0.8
 38000 -49.2 -56.6  325  23 12   1.1   0.6 | -49.9 -57.8  335  30 15  -0.8  -0.4
 36000 -48.6 -55.5  335  25 13   1.1   0.6 | -50.2 -58.4  345  34 17  -0.6  -0.3
 34000 -47.9 -54.2  345  28 14   1.1   0.6 | -50.6 -59.1  355  39 20  -0.6  -0.3
 32000 -47.7 -53.9  360  34 18  -0.0  -0.0 | -50.6 -59.1  010  51 26   0.1   0.0
 30000 -47.7 -53.9  010  45 23  -0.1  -0.0 | -50.6 -59.1  015  65 34  -0.4  -0.2
 29000 -47.5 -53.5  015  47 24   1.2   0.7 | -49.5 -57.1  020  68 35   5.0   2.7
 28000 -47.1 -52.8  010  46 24   1.3   0.7 | -48.0 -54.4  020  69 36   5.0   2.7
 27000 -46.8 -52.2  010  46 24   1.2   0.7 | -46.5 -51.7  020  71 36   5.0   2.7
 26000 -46.2 -51.2  010  45 23   3.7   2.0 | -44.7 -48.5  020  71 36   7.3   4.0
 25000 -45.2 -49.4  005  38 20   3.6   2.0 | -42.6 -44.7  020  68 35   7.2   3.9
 24000 -44.1 -47.4  360  31 16   3.5   1.9 | -40.4 -40.7  025  66 34   7.2   3.9
 23000 -42.8 -45.0  350  27 14   7.2   3.9 | -38.4 -37.1  025  62 32   5.6   3.1
 22000 -40.8 -41.4  355  25 13   6.8   3.7 | -36.7 -34.1  020  54 28   5.7   3.1
 21000 -38.7 -37.7  355  24 12   6.8   3.7 | -35.0 -31.0  015  46 24   5.7   3.1
 20000 -36.6 -33.9  360  23 12   7.7   4.2 | -33.3 -27.9  010  40 21   5.7   3.1
 19500 -35.4 -31.7  360  23 12   7.7   4.2 | -32.5 -26.5  010  38 19   5.7   3.1
 19000 -34.3 -29.7  360  24 12   7.7   4.2 | -31.6 -24.9  005  35 18   5.7   3.1
 18500 -33.1 -27.6  360  24 12   7.7   4.2 | -30.8 -23.4  005  33 17   5.5   3.0
 18000 -31.9 -25.4  360  24 12   8.5   4.7 | -29.8 -21.6  360  31 16   8.3   4.5
 17500 -30.6 -23.1  355  23 12   8.7   4.7 | -28.5 -19.3  360  30 15   8.3   4.6
 17000 -29.3 -20.7  350  23 12   8.5   4.7 | -27.3 -17.1  355  29 15   7.2   4.0
 16500 -28.1 -18.6  350  24 12   8.3   4.5 | -25.9 -14.6  355  30 15   6.4   3.5
 16000 -26.2 -15.2  355  24 13   8.3   4.5 | -24.9 -12.8  355  30 15   6.7   3.7
 15500 -25.0 -13.0  355  24 12   8.3   4.6 | -23.9 -11.0  350  29 15   6.7   3.7
 15000 -23.8 -10.8  355  24 12   8.8   4.8 | -22.9  -9.2  350  29 15   7.4   4.1
 14500 -22.4  -8.3  355  24 12   9.1   5.0 | -21.7  -7.1  350  28 14   7.7   4.2
 14000 -21.0  -5.8  355  23 12   8.8   4.8 | -20.6  -5.1  345  27 14   7.5   4.1
 13500 -19.8  -3.6  355  23 12   8.5   4.6 | -19.5  -3.1  345  26 13   7.4   4.1
 13000 -18.5  -1.3  355  22 12   8.3   4.6 | -18.4  -1.1  345  25 13   7.0   3.9
 12500 -17.3   0.9  360  21 11   8.1   4.4 | -17.4   0.7  340  22 11   6.8   3.7
 12000 -16.1   3.0  360  20 10   7.7   4.2 | -16.4   2.5  340  19 10   6.9   3.8
 11500 -15.1   4.8  360  18  9   7.3   4.0 | -15.4   4.3  340  18  9   6.9   3.8
 11000 -14.0   6.8  005  17  9   7.1   3.9 | -14.3   6.3  340  17  9   7.7   4.2
 10500 -13.0   8.6  010  17  9   7.2   3.9 | -13.1   8.4  340  17  9   8.1   4.4
 10250 -12.5   9.5  010  17  9   6.8   3.7 | -12.6   9.3  345  17  9   7.1   3.9
 10000 -12.0  10.4  010  18  9   5.6   3.1 | -12.1  10.2  345  17  9   5.2   2.9
  9750 -11.5  11.3  010  19 10   7.6   4.2 | -11.7  10.9  350  17  9   7.9   4.3
  9500 -10.9  12.4  010  21 11   9.8   5.4 | -11.0  12.2  350  19 10  10.5   5.8
  9250 -10.2  13.6  010  23 12   8.2   4.5 | -10.2  13.6  355  20 10   8.2   4.5
  9000  -9.6  14.7  010  24 12   6.5   3.6 |  -9.7  14.5  355  21 11   6.4   3.5
  8750  -9.1  15.6  005  25 13   8.1   4.4 |  -9.2  15.4  355  22 11   8.6   4.7
  8500  -8.4  16.9  005  26 14   9.1   5.0 |  -8.5  16.7  355  24 12   9.9   5.4
  8250  -7.8  18.0  360  27 14   8.2   4.5 |  -7.8  18.0  355  24 13   8.6   4.7
  8000  -7.2  19.0  355  26 13   7.4   4.1 |  -7.1  19.2  355  24 12   8.3   4.5
  7750  -6.6  20.1  350  26 13   9.0   4.9 |  -6.5  20.3  355  24 12   8.9   4.9
  7500  -5.9  21.4  350  24 12   8.1   4.4 |  -5.8  21.6  355  23 12   8.7   4.8
  7250  -5.4  22.3  345  22 11   6.0   3.3 |  -5.2  22.6  350  21 11   7.9   4.3
  7000  -5.0  23.0  340  20 10   6.5   3.6 |  -4.6  23.7  345  19 10   8.5   4.7
  6750  -4.5  23.9  335  19 10   6.4   3.5 |  -4.0  24.8  340  17  9   7.1   3.9
  6500  -4.0  24.8  330  17  9   4.2   2.3 |  -3.5  25.7  330  16  8   5.0   2.7
  6250  -3.8  25.2  320  17  9   3.4   1.9 |  -3.1  26.4  325  14  7   6.3   3.4
  6000  -3.6  25.5  310  17  9   0.9   0.5 |  -2.7  27.1  310  14  7   2.0   1.1
  5750  -3.8  25.2  305  15  8  -7.0  -3.8 |  -2.9  26.8  305  11  6  -0.2  -0.1
  5500  -4.6  23.7  295  10  5 -10.7  -5.9 |  -2.6  27.3  295   8  4   8.9   4.9

           02/05/2016 at 1400 MST          |       02/05/2016 at 1700 MST
                                           |
K index... -5.6  LI... +7.3                | K index... -8.6  LI... +7.6
CAPE... 0.0  CIN... -1.2                   | CAPE... 0.0  CIN... -0.4
                                           |
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 -54.5 -66.1  305  20 10   0.4   0.2 | -54.6 -66.3  305  24 12  -0.0  -0.0
 45000 -53.9 -65.0  320  24 12   0.4   0.2 | -54.6 -66.3  310  25 13  -0.0  -0.0
 40000 -52.0 -61.6  340  33 17   1.3   0.7 | -54.9 -66.8  340  46 24  -0.2  -0.1
 38000 -51.5 -60.7  345  39 20  -1.6  -0.9 | -55.0 -67.0  350  56 29  -0.1  -0.0
 36000 -52.4 -62.3  360  50 26  -1.5  -0.8 | -55.1 -67.2  360  68 35  -0.1  -0.0
 34000 -53.4 -64.1  005  63 32  -1.6  -0.9 | -55.1 -67.2  010  81 42  -0.5  -0.3
 32000 -52.4 -62.3  005  65 33   2.3   1.3 | -52.6 -62.7  005  79 41   4.2   2.3
 30000 -50.9 -59.6  005  63 32   3.3   1.8 | -50.1 -58.2  005  75 38   5.3   2.9
 29000 -49.3 -56.7  005  64 33   5.8   3.2 | -48.3 -54.9  005  74 38   5.9   3.3
 28000 -47.5 -53.5  005  65 33   5.7   3.2 | -46.6 -51.9  005  72 37   5.9   3.3
 27000 -45.8 -50.4  010  65 34   5.8   3.2 | -44.8 -48.6  005  71 37   5.8   3.2
 26000 -43.8 -46.8  010  64 33   7.6   4.2 | -42.5 -44.5  005  70 36   8.8   4.8
 25000 -41.5 -42.7  010  60 31   7.7   4.2 | -39.8 -39.6  360  67 35   8.8   4.8
 24000 -39.2 -38.6  010  56 29   7.7   4.2 | -37.2 -35.0  360  65 34   8.9   4.9
 23000 -36.9 -34.4  010  53 27   7.7   4.2 | -34.8 -30.6  360  62 32   7.6   4.2
 22000 -34.6 -30.3  010  50 26   7.7   4.2 | -32.5 -26.5  360  57 29   7.6   4.2
 21000 -32.3 -26.1  005  48 25   7.7   4.2 | -30.2 -22.4  005  52 27   7.5   4.1
 20000 -29.9 -21.8  005  45 23   8.3   4.6 | -28.2 -18.8  005  47 24   6.7   3.7
 19500 -28.6 -19.5  005  44 23   8.3   4.6 | -27.2 -17.0  360  45 23   6.7   3.7
 19000 -27.4 -17.3  005  43 22   8.3   4.6 | -26.2 -15.2  360  43 22   6.7   3.7
 18500 -26.1 -15.0  005  42 22   8.5   4.7 | -25.2 -13.4  360  41 21   6.7   3.7
 18000 -25.1 -13.2  005  41 21   5.8   3.2 | -24.2 -11.6  355  39 20   7.1   3.9
 17500 -24.1 -11.4  005  39 20   6.0   3.3 | -23.1  -9.6  355  37 19   7.1   3.9
 17000 -23.3  -9.9  360  37 19   5.4   3.0 | -22.1  -7.8  355  36 18   6.6   3.6
 16500 -22.1  -7.8  360  35 18   5.3   2.9 | -20.6  -5.1  355  34 17   6.6   3.6
 16000 -21.4  -6.5  355  33 17   4.5   2.5 | -19.7  -3.5  355  32 17   5.8   3.2
 15500 -20.7  -5.3  355  31 16   4.5   2.5 | -18.8  -1.8  355  31 16   5.9   3.3
 15000 -20.1  -4.2  350  30 15   4.1   2.2 | -18.0  -0.4  350  30 15   4.3   2.3
 14500 -19.5  -3.1  350  29 15   4.0   2.2 | -17.4   0.7  350  29 15   4.0   2.2
 14000 -18.9  -2.0  345  28 14   4.6   2.5 | -16.8   1.8  345  28 14   4.4   2.4
 13500 -18.1  -0.6  340  27 14   5.0   2.7 | -16.1   3.0  345  26 14   4.6   2.5
 13000 -17.4   0.7  340  27 14   5.9   3.3 | -15.4   4.3  340  25 13   5.1   2.8
 12500 -16.4   2.5  335  25 13   6.6   3.6 | -14.6   5.7  340  24 13   5.3   2.9
 12000 -15.4   4.3  335  23 12   6.5   3.6 | -13.8   7.2  340  24 12   6.0   3.3
 11500 -14.4   6.1  335  21 11   6.4   3.5 | -12.8   9.0  340  21 11   6.3   3.5
 11000 -13.5   7.7  330  20 10   7.6   4.2 | -11.9  10.6  340  19 10   7.4   4.1
 10500 -12.3   9.9  335  19 10   8.2   4.5 | -10.7  12.7  330  17  9   7.9   4.3
 10250 -11.7  10.9  335  18  9   7.3   4.0 | -10.2  13.6  330  16  8   7.2   4.0
 10000 -11.2  11.8  335  18  9   5.9   3.2 |  -9.7  14.5  325  16  8   6.6   3.6
  9750 -10.7  12.7  335  17  9   8.3   4.6 |  -9.1  15.6  325  17  9   8.7   4.8
  9500 -10.0  14.0  335  16  8  10.4   5.7 |  -8.4  16.9  315  20 10  10.8   5.9
  9250  -9.3  15.3  330  15  8   8.6   4.7 |  -7.7  18.1  310  22 11   7.2   3.9
  9000  -8.7  16.3  330  15  8   7.1   3.9 |  -7.3  18.9  310  23 12   3.8   2.1
  8750  -8.1  17.4  325  14  7   9.1   5.0 |  -7.0  19.4  305  24 12   6.4   3.5
  8500  -7.4  18.7  325  13  7   9.8   5.4 |  -6.4  20.5  300  24 13   8.1   4.4
  8250  -6.7  19.9  320  13  7   7.9   4.3 |  -5.8  21.6  300  24 12   7.8   4.3
  8000  -6.2  20.8  315  12  6   7.1   3.9 |  -5.3  22.5  300  23 12   7.7   4.3
  7750  -5.6  21.9  310  11  6   8.9   4.9 |  -4.7  23.5  300  22 11   8.7   4.8
  7500  -4.9  23.2  305  11  6   9.0   4.9 |  -4.0  24.8  300  21 11   7.9   4.3
  7250  -4.3  24.3  305  10  5   7.4   4.1 |  -3.5  25.7  300  19 10   6.3   3.5
  7000  -3.7  25.3  300   9  5   7.8   4.3 |  -3.0  26.6  300  16  8   6.8   3.7
  6750  -3.2  26.2  295   9  5   7.9   4.3 |  -2.6  27.3  295  14  7   6.5   3.6
  6500  -2.6  27.3  290   8  4   7.0   3.8 |  -2.1  28.2  290  12  6   5.8   3.2
  6250  -2.2  28.0  280   6  3   6.2   3.4 |  -1.7  28.9  280  11  5   5.5   3.0
  6000  -1.7  28.9  270   5  3   6.1   3.3 |  -1.3  29.7  265   9  5   5.3   2.9
  5750  -1.3  29.7  255   4  2   6.9   3.8 |  -1.1  30.0  250   8  4  -1.9  -1.0
  5500  -0.8  30.6  235   3  2   9.7   5.3 |  -1.8  28.8  235   6  3 -13.0  -7.2
________________________________________________________________________________

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



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.