Soaring Guidance
Issued by NWS Denver/Boulder, CO

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218
UXUS97 KBOU 031243
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0543 MST Wednesday, February 3, 2016

This forecast is for Wednesday, February 3, 2016:

If the trigger temperature of 26.8 F/-2.9 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 367 ft/min (1.9 m/s)
   Maximum height of thermals.................. 12007 ft MSL (6722 ft AGL)

Forecast maximum temperature................... 29.0 F/-2.1 C
Time of trigger temperature.................... 1100 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6361 ft MSL (1075 ft AGL)
Thermal soaring outlook for Thursday 02/04..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Little change
Height of stable layer (12-18K ft MSL)......... 16584 ft MSL (11299 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 22479 ft MSL (17194 ft AGL)
Wave soaring outlook for Thursday 02/04........ Fair

Remarks... Mountain wave forms along the front range tonight

Sunrise/Sunset.................... 07:05:45 / 17:19:49 MST
Total possible sunshine........... 10 hr 14 min 4 sec (614 min 4 sec)
Altitude of sun at 12:13:09 MST... 33.76 degrees

Upper air data from rawinsonde observation taken on 02/03/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 11196 ft MSL (5911 ft AGL)
Lifted condensation level....... 11502 ft MSL (6217 ft AGL)
Lifted index.................... +8.2
K index......................... +3.4

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  -50.2 -58.4   280   23   12   4.2   2.3  121.1 250.0    69.4      M    M
 45000  -47.4 -53.3   275   33   17  -0.0  -0.0  101.0 213.7    61.9      M    M
 40000  -45.3 -49.5   285   13    6  -8.2  -4.5   79.9 175.8    52.6      M    M
 38000  -46.7 -52.1   285   28   14  -4.8  -2.6   68.9 156.1    46.7      M    M
 36000  -47.7 -53.9   285   34   18  -1.4  -0.8   58.6 137.5    41.0      M    M
 34000  -50.4 -58.7   300   29   15  -9.4  -5.2   46.2 115.1    33.4      M    M
 32000  -50.6 -59.1   280   27   14   3.8   2.1   37.7  99.9    28.2      M    M
 30000  -52.6 -62.7   290   32   16 -16.1  -8.9   26.9  80.5    21.0      M    M
 29000  -52.5 -62.5   270   28   15   1.4   0.7   23.1  73.6    18.5      M    M
 28000  -54.4 -65.9   290   23   12   5.5   3.0   15.7  60.3    13.2      M    M
 27000  -52.5 -62.5   300   26   13   8.5   4.7   14.3  57.8    12.3      M    M
 26000  -50.0 -58.0   305   29   15   8.3   4.6   13.8  56.8    12.0      M    M
 25000  -47.6 -53.7   310   32   17   7.6   4.2   13.1  55.6    11.7      M    M
 24000  -45.4 -49.7   310   36   18   7.1   3.9   12.3  54.2    11.2      M    M
 23000  -43.4 -46.1   315   39   20   6.5   3.6   11.1  51.9    10.3      M    M
 22000  -41.3 -42.3   320   41   21   7.4   4.1   10.2  50.3     9.7      M    M
 21000  -38.9 -38.0   320   36   18   8.3   4.6    9.5  49.1     9.2      M    M
 20000  -36.7 -34.1   315   31   16   5.5   3.0    8.5  47.4     8.6      M    M
 19500  -35.9 -32.6   315   29   15   3.7   2.0    7.8  46.0     8.0      M    M
 19000  -35.6 -32.1   310   26   13  -1.6  -0.9    6.5  43.7     6.9      M    M
 18500  -35.7 -32.3   310   24   12   5.9   3.2    4.6  40.2     5.3      M    M
 18000  -34.6 -30.3   305   22   11   6.4   3.5    4.2  39.5     5.0      M    M
 17500  -33.6 -28.5   300   19   10   8.1   4.5    3.7  38.6     4.6      M    M
 17000  -32.4 -26.3   295   17    9   7.0   3.8    3.4  38.1     4.4      M    M
 16500  -31.8 -25.2   295   17    9   2.9   1.6    2.4  36.4     3.5      M    M
 16000  -31.3 -24.3   300   16    8   3.0   1.7    1.3  34.3     2.6      M    M
 15500  -30.8 -23.4   305   16    8   6.0   3.3    0.3  32.5     1.6      M    M
 15000  -29.5 -21.1   310   17    9   8.9   4.9    0.0  32.0     1.4      M    M
 14500  -28.2 -18.8   315   18    9   9.0   4.9   -0.1  31.8     1.3      M    M
 14000  -26.2 -15.2   320   19   10   9.0   4.9   -0.3  31.5     1.2      M    M
 13500  -24.8 -12.6   315   19   10   9.0   5.0   -0.4  31.3     1.1      M    M
 13000  -23.5 -10.3   315   19   10   9.4   5.2   -0.5  31.0     1.0      M    M
 12500  -22.4  -8.3   310   20   10   4.8   2.6   -0.9  30.3     0.6      M    M
 12000  -21.7  -7.1   310   20   10   4.4   2.4   -1.7  29.0    -0.1    561  2.8
 11500  -20.6  -5.1   310   18    9   9.5   5.2   -2.2  28.1    -0.6    515  2.6
 11000  -19.3  -2.7   310   16    8   9.1   5.0   -2.3  27.9    -0.7    460  2.3
 10500  -17.9  -0.2   310   14    7   9.1   5.0   -2.4  27.7    -0.8    405  2.1
 10250  -17.3   0.9   310   13    7   9.0   5.0   -2.4  27.6    -0.9    377  1.9
 10000  -16.6   2.1   310   12    6   9.2   5.1   -2.5  27.5    -0.9    349  1.8
  9750  -15.9   3.4   310   11    6   8.8   4.8   -2.5  27.5    -0.9    322  1.6
  9500  -15.3   4.5   300   11    6   7.7   4.3   -2.6  27.3    -1.1    296  1.5
  9250  -14.7   5.5   295   11    6   7.8   4.3   -2.8  27.0    -1.2    272  1.4
  9000  -14.2   6.4   290   11    6   7.1   3.9   -3.0  26.7    -1.4    247  1.3
  8750  -13.7   7.3   290   10    5   7.1   3.9   -3.2  26.3    -1.7    225  1.1
  8500  -13.1   8.4   285    8    4   8.3   4.5   -3.3  26.0    -1.8    201  1.0
  8250  -12.5   9.5   285    7    4   8.5   4.7   -3.4  25.8    -1.9    174  0.9
  8000  -11.9  10.6   280    6    3   8.4   4.6   -3.5  25.6    -2.0    148  0.8
  7750  -11.2  11.8   280    6    3   8.4   4.6   -3.6  25.4    -2.1    122  0.6
  7500  -10.6  12.9   280    5    3   8.4   4.6   -3.7  25.3    -2.2     96  0.5
  7250  -10.0  14.0   280    5    3   8.5   4.6   -3.8  25.1    -2.3     69  0.4
  7000   -9.3  15.3   280    5    3   8.3   4.6   -3.9  24.9    -2.4     43  0.2
  6750   -8.7  16.3   265    6    3   8.9   4.9   -4.0  24.7    -2.6     17  0.1
  6500   -8.1  17.4   250    6    3   6.7   3.6   -4.2  24.5    -2.7      M    M
  6250   -7.9  17.8   240    8    4  -2.4  -1.3   -4.7  23.5    -3.2      M    M
  6000   -8.4  16.9   235    9    5  -9.5  -5.2   -5.9  21.3    -4.4      M    M
  5750   -9.3  15.3   240    7    4 -15.6  -8.6   -7.6  18.3    -6.1      4  0.0
  5500  -10.9  12.4   240    6    3 -27.8 -15.3   -9.9  14.1    -8.5     45  0.2

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

           02/03/2016 at 0800 MST          |       02/03/2016 at 1100 MST
                                           |
K index... +0.1  LI... +1.9                | K index... 0.0  LI... +1.5
CAPE... 0.0  CIN... -0.0                   | 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 -49.3 -56.7  270  20 10   1.6   0.9 | -49.4 -56.9  270  20 10   1.8   1.0
 45000 -46.8 -52.2  270  25 13   1.6   0.9 | -46.7 -52.1  275  25 13   1.8   1.0
 40000 -46.3 -51.3  280  25 13  -0.1  -0.0 | -46.7 -52.1  280  26 13  -0.5  -0.3
 38000 -46.4 -51.5  285  25 13   0.1   0.0 | -47.0 -52.6  285  26 13  -0.5  -0.3
 36000 -47.0 -52.6  290  26 14  -1.3  -0.7 | -47.3 -53.1  295  27 14  -0.5  -0.3
 34000 -47.8 -54.0  295  28 15  -1.3  -0.7 | -47.7 -53.9  305  29 15  -0.5  -0.3
 32000 -48.9 -56.0  295  32 16  -2.8  -1.5 | -48.3 -54.9  310  32 17  -2.0  -1.1
 30000 -50.5 -58.9  290  37 19  -2.8  -1.5 | -49.6 -57.3  310  36 19  -2.0  -1.1
 29000 -51.5 -60.7  290  40 21  -0.3  -0.2 | -50.2 -58.4  310  38 19   0.1   0.1
 28000 -51.1 -60.0  290  42 22   1.3   0.7 | -49.8 -57.6  310  37 19   1.1   0.6
 27000 -50.8 -59.4  290  43 22   1.3   0.7 | -49.5 -57.1  315  37 19   1.1   0.6
 26000 -50.4 -58.7  290  45 23   0.7   0.4 | -49.1 -56.4  315  37 19   0.8   0.5
 25000 -48.8 -55.8  290  45 23   6.8   3.7 | -48.1 -54.6  315  36 18   4.2   2.3
 24000 -46.8 -52.2  290  45 23   6.8   3.7 | -46.9 -52.4  315  34 18   4.2   2.3
 23000 -44.8 -48.6  295  45 23   6.9   3.8 | -45.6 -50.1  315  33 17   4.1   2.2
 22000 -42.9 -45.2  295  42 21   6.1   3.3 | -44.0 -47.2  315  31 16   5.7   3.1
 21000 -41.0 -41.8  295  37 19   6.1   3.3 | -42.3 -44.1  315  29 15   5.7   3.1
 20000 -39.3 -38.7  295  33 17   4.6   2.5 | -40.6 -41.1  315  28 14   5.1   2.8
 19500 -38.7 -37.7  295  32 16   4.2   2.3 | -39.9 -39.8  320  27 14   4.9   2.7
 19000 -38.0 -36.4  300  30 16   4.1   2.3 | -39.2 -38.6  320  26 14   4.9   2.7
 18500 -37.4 -35.3  305  29 15   4.1   2.3 | -38.4 -37.1  325  26 13   4.9   2.7
 18000 -36.8 -34.2  305  28 14   4.0   2.2 | -37.7 -35.9  325  25 13   4.7   2.6
 17500 -36.1 -33.0  310  27 14   5.8   3.2 | -36.9 -34.4  330  25 13   6.6   3.6
 17000 -35.2 -31.4  310  26 13   5.9   3.2 | -35.9 -32.6  330  24 12   6.6   3.6
 16500 -34.3 -29.7  315  25 13   7.0   3.9 | -34.9 -30.8  330  23 12   7.9   4.3
 16000 -33.2 -27.8  315  25 13   7.8   4.3 | -33.6 -28.5  330  22 11   8.4   4.6
 15500 -32.0 -25.6  320  25 13   8.3   4.6 | -31.7 -25.1  330  20 10   8.5   4.7
 15000 -30.0 -22.0  315  25 13   9.2   5.1 | -30.4 -22.7  330  20 10   8.5   4.7
 14500 -28.6 -19.5  315  24 13   8.9   4.9 | -29.2 -20.6  330  19 10   8.5   4.7
 14000 -27.3 -17.1  315  24 12   8.9   4.9 | -27.9 -18.2  330  18  9   8.5   4.7
 13500 -26.0 -14.8  315  23 12   9.0   5.0 | -26.6 -15.9  330  17  9   8.6   4.7
 13000 -24.6 -12.3  315  22 11   9.1   5.0 | -25.4 -13.7  330  16  8   8.6   4.7
 12500 -23.3  -9.9  320  21 11   9.0   4.9 | -24.0 -11.2  330  16  8   9.2   5.0
 12000 -21.9  -7.4  320  19 10   9.0   5.0 | -22.7  -8.9  335  15  8   9.2   5.1
 11500 -20.6  -5.1  320  18  9   8.5   4.7 | -21.3  -6.3  335  15  8   9.0   5.0
 11000 -19.4  -2.9  315  16  8   8.5   4.7 | -19.9  -3.8  340  15  8   9.0   5.0
 10500 -18.1  -0.6  315  15  8   8.0   4.4 | -18.6  -1.5  340  15  8   8.8   4.8
 10250 -17.5   0.5  320  14  7   9.0   4.9 | -17.9  -0.2  345  15  8  10.0   5.5
 10000 -16.9   1.6  320  13  7   5.4   2.9 | -17.2   1.0  345  15  8   5.3   2.9
  9750 -16.6   2.1  320  13  7   6.2   3.4 | -17.0   1.4  345  15  8   6.4   3.5
  9500 -15.9   3.4  320  13  7  10.3   5.7 | -16.2   2.8  345  16  8  11.8   6.5
  9250 -15.2   4.6  320  12  6   9.5   5.2 | -15.4   4.3  345  17  9  10.9   6.0
  9000 -14.5   5.9  320  12  6   8.6   4.7 | -14.6   5.7  345  17  9   9.1   5.0
  8750 -13.9   7.0  320  11  6   8.2   4.5 | -14.0   6.8  345  18  9   8.2   4.5
  8500 -13.2   8.2  320  12  6   9.5   5.2 | -13.3   8.1  345  18  9  10.5   5.8
  8250 -12.5   9.5  320  12  6   9.4   5.2 | -12.5   9.5  345  18  9   9.9   5.4
  8000 -11.8  10.8  320  13  7   9.1   5.0 | -11.8  10.8  340  18  9   9.0   4.9
  7750 -11.1  12.0  320  14  7   8.4   4.6 | -11.1  12.0  340  18  9   8.6   4.7
  7500 -10.5  13.1  320  16  8   8.8   4.8 | -10.5  13.1  335  18  9   8.5   4.6
  7250  -9.9  14.2  320  18  9   6.4   3.5 |  -9.9  14.2  335  18  9   6.8   3.7
  7000  -9.6  14.7  310  20 10   3.7   2.1 |  -9.5  14.9  325  18  9   5.9   3.2
  6750  -9.2  15.4  305  21 11   4.9   2.7 |  -9.0  15.8  320  19 10   5.2   2.9
  6500  -8.9  16.0  300  22 12   0.7   0.4 |  -8.7  16.3  315  19 10   3.5   1.9
  6250  -9.2  15.4  295  21 11  -5.6  -3.1 |  -8.5  16.7  310  16  8   3.3   1.8
  6000  -9.6  14.7  290  18  9  -5.5  -3.0 |  -8.3  17.1  305  13  7   3.6   2.0
  5750 -10.1  13.8  285  16  8  -8.6  -4.7 |  -8.0  17.6  295  10  5   2.8   1.5
  5500 -11.5  11.3  275  11  6 -34.0 -18.7 |  -7.9  17.8  285   7  4   3.3   1.8

           02/03/2016 at 1400 MST          |       02/03/2016 at 1700 MST
                                           |
K index... -1.9  LI... +1.2                | K index... -4.0  LI... +3.4
CAPE... +20.0  CIN... -25.3                | 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 -49.9 -57.8  265  20 10   1.4   0.8 | -50.8 -59.4  275  23 12   0.7   0.4
 45000 -47.7 -53.9  275  21 11   1.4   0.8 | -49.7 -57.5  285  27 14   0.7   0.4
 40000 -46.5 -51.7  295  24 13   0.6   0.3 | -48.4 -55.1  305  29 15   0.9   0.5
 38000 -46.2 -51.2  300  26 14   0.8   0.4 | -47.9 -54.2  310  30 16   0.7   0.4
 36000 -47.0 -52.6  310  30 15  -1.7  -0.9 | -48.6 -55.5  325  35 18  -1.5  -0.8
 34000 -48.1 -54.6  320  34 17  -1.7  -0.9 | -49.5 -57.1  335  42 22  -1.4  -0.8
 32000 -49.0 -56.2  330  37 19  -1.3  -0.7 | -50.2 -58.4  345  49 25  -0.9  -0.5
 30000 -49.8 -57.6  335  40 21  -1.3  -0.7 | -50.8 -59.4  350  56 29  -0.9  -0.5
 29000 -50.1 -58.2  335  41 21   1.2   0.7 | -50.9 -59.6  350  59 30   2.5   1.4
 28000 -49.6 -57.3  340  41 21   1.8   1.0 | -50.2 -58.4  350  58 30   2.3   1.2
 27000 -49.0 -56.2  340  40 21   1.8   1.0 | -49.5 -57.1  350  58 30   2.3   1.2
 26000 -48.5 -55.3  340  40 21   1.6   0.9 | -48.9 -56.0  355  58 30   2.8   1.6
 25000 -47.5 -53.5  340  39 20   3.7   2.0 | -47.3 -53.1  355  56 29   5.7   3.1
 24000 -46.4 -51.5  345  39 20   3.7   2.0 | -45.6 -50.1  360  55 28   5.7   3.1
 23000 -45.3 -49.5  345  38 20   3.7   2.0 | -43.9 -47.0  360  54 28   5.8   3.2
 22000 -43.8 -46.8  340  37 19   5.4   3.0 | -42.1 -43.8  360  51 26   6.0   3.3
 21000 -42.2 -44.0  340  36 19   5.4   3.0 | -40.3 -40.5  360  48 25   6.0   3.3
 20000 -40.5 -40.9  340  35 18   5.7   3.2 | -38.5 -37.3  360  45 23   6.0   3.3
 19500 -39.7 -39.5  340  34 18   5.8   3.2 | -37.6 -35.7  360  43 22   6.0   3.3
 19000 -38.8 -37.8  340  33 17   5.8   3.2 | -36.7 -34.1  355  41 21   6.0   3.3
 18500 -37.9 -36.2  340  32 17   5.8   3.2 | -35.8 -32.4  355  40 20   6.0   3.3
 18000 -37.1 -34.8  335  32 16   5.7   3.2 | -34.9 -30.8  355  38 19   6.0   3.3
 17500 -36.2 -33.2  335  31 16   6.1   3.3 | -34.1 -29.4  350  36 18   5.5   3.0
 17000 -35.3 -31.5  335  30 15   6.0   3.3 | -33.3 -27.9  350  33 17   5.5   3.0
 16500 -34.3 -29.7  335  29 15   6.9   3.8 | -32.4 -26.3  345  32 16   6.2   3.4
 16000 -33.3 -27.9  330  29 15   7.1   3.9 | -31.5 -24.7  345  30 16   6.3   3.4
 15500 -31.5 -24.7  330  28 15   9.4   5.2 | -30.0 -22.0  340  29 15   6.9   3.8
 15000 -30.2 -22.4  330  27 14   9.2   5.1 | -29.0 -20.2  340  28 15   6.7   3.7
 14500 -28.8 -19.8  325  27 14   9.2   5.0 | -27.8 -18.0  335  28 14   8.7   4.8
 14000 -27.4 -17.3  325  26 13   9.2   5.1 | -26.6 -15.9  335  27 14   8.5   4.7
 13500 -26.1 -15.0  330  26 13   8.8   4.8 | -25.3 -13.5  330  26 13   8.6   4.7
 13000 -24.8 -12.6  330  25 13   8.8   4.8 | -24.0 -11.2  330  25 13   8.5   4.7
 12500 -23.4 -10.1  330  25 13   8.9   4.9 | -22.7  -8.9  325  24 12   9.0   4.9
 12000 -22.1  -7.8  330  23 12   8.9   4.9 | -21.4  -6.5  320  23 12   9.0   4.9
 11500 -20.8  -5.4  330  22 12   9.0   5.0 | -20.1  -4.2  320  22 11   9.0   4.9
 11000 -19.4  -2.9  330  21 11   9.0   4.9 | -18.7  -1.7  315  21 11   8.9   4.9
 10500 -18.1  -0.6  330  21 11   8.9   4.9 | -17.4   0.7  315  21 11   8.5   4.7
 10250 -17.4   0.7  330  20 10  10.4   5.7 | -16.8   1.8  310  20 10   9.8   5.4
 10000 -16.7   1.9  330  20 10   4.8   2.7 | -16.1   3.0  310  20 10   5.0   2.7
  9750 -16.5   2.3  330  20 10   6.3   3.5 | -15.9   3.4  310  20 10   6.2   3.4
  9500 -15.6   3.9  330  19 10  12.9   7.1 | -15.1   4.8  310  19 10  11.9   6.5
  9250 -14.8   5.4  330  18 10  11.5   6.3 | -14.3   6.3  310  19 10  10.4   5.7
  9000 -14.0   6.8  330  18  9   8.0   4.4 | -13.5   7.7  305  18  9   8.8   4.8
  8750 -13.5   7.7  330  17  9   7.2   3.9 | -12.9   8.8  305  18  9   8.1   4.5
  8500 -12.8   9.0  330  17  9  10.7   5.9 | -12.2  10.0  305  17  9   9.5   5.2
  8250 -12.0  10.4  330  16  8   9.8   5.4 | -11.6  11.1  305  16  8   8.9   4.9
  8000 -11.3  11.7  325  15  8   8.7   4.8 | -10.9  12.4  305  15  8   8.2   4.5
  7750 -10.7  12.7  325  15  8   9.1   5.0 | -10.3  13.5  305  14  7   8.7   4.8
  7500 -10.0  14.0  320  14  7   9.6   5.3 |  -9.6  14.7  305  13  7   9.1   5.0
  7250  -9.3  15.3  320  14  7   8.5   4.7 |  -9.0  15.8  300  12  6   8.3   4.6
  7000  -8.7  16.3  315  13  7   8.1   4.5 |  -8.4  16.9  300  11  6   8.0   4.4
  6750  -8.1  17.4  315  12  6   7.3   4.0 |  -7.8  18.0  300  10  5   7.8   4.3
  6500  -7.6  18.3  310  11  5   7.4   4.1 |  -7.2  19.0  295   9  5   7.5   4.1
  6250  -7.0  19.4  305   9  4   8.6   4.7 |  -6.7  19.9  290   8  4   7.0   3.8
  6000  -6.4  20.5  295   7  3   8.3   4.5 |  -6.2  20.8  280   8  4   8.7   4.8
  5750  -5.8  21.6  285   5  3   8.7   4.8 |  -5.6  21.9  270   7  4   2.6   1.5
  5500  -5.2  22.6  275   4  2   9.8   5.4 |  -6.0  21.2  255   6  3 -12.6  -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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