Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 271313
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0612 MST Friday, February 27, 2015

This forecast is for Friday, February 27, 2015:

If the trigger temperature of 17.7 F/-7.9 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 310 ft/min (1.6 m/s)
   Maximum height of thermals.................. 9852 ft MSL (4567 ft AGL)

Forecast maximum temperature................... 20.0 F/-7.1 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................. 7940 ft MSL (2655 ft AGL)
Thermal soaring outlook for Saturday 02/28..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 24504 ft MSL (19219 ft AGL)
Wave soaring outlook for Saturday 02/28........ Fair

Remarks... Moderate westerly flow aloft across colorado today. Arctic airmass in
           place on the plains with top of the cold air around 10000 ft msl and
           a strong inversion at that level.

Sunrise/Sunset.................... 06:35:40 / 17:47:58 MST
Total possible sunshine........... 11 hr 12 min 17 sec (672 min 17 sec)
Altitude of sun at 12:12:04 MST... 42.01 degrees

Upper air data from rawinsonde observation taken on 02/27/2015 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 15847 ft MSL (10562 ft AGL)
Lifted condensation level....... 10585 ft MSL (5299 ft AGL)
Lifted index.................... +15.7
K index......................... -5.8

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  -51.8 -61.2   280   40   20   2.5   1.4  118.2 244.7    70.6      M    M
 45000  -49.9 -57.8   290   48   25  -4.4  -2.4   96.3 205.3    62.2      M    M
 40000  -50.3 -58.5   285   41   21   4.0   2.2   72.3 162.1    50.9      M    M
 38000  -49.8 -57.6   285   39   20  -1.2  -0.6   64.1 147.4    46.9      M    M
 36000  -50.3 -58.5   285   41   21  -3.8  -2.1   54.5 130.2    41.6      M    M
 34000  -52.9 -63.2   290   43   22  -4.3  -2.4   42.1 107.8    34.1      M    M
 32000  -56.8 -70.2   285   44   23   3.2   1.8   27.6  81.6    24.6      M    M
 30000  -54.7 -66.5   280   45   23   5.9   3.3   22.3  72.2    21.4      M    M
 29000  -52.9 -63.2   280   46   24   7.1   3.9   20.9  69.6    20.6      M    M
 28000  -50.8 -59.4   280   46   24   7.1   3.9   19.8  67.6    20.1      M    M
 27000  -48.6 -55.5   275   46   24   7.1   3.9   18.6  65.6    19.5      M    M
 26000  -46.5 -51.7   275   46   24   7.1   3.9   17.7  63.8    19.0      M    M
 25000  -44.4 -47.9   275   46   24   7.1   3.9   16.8  62.3    18.5      M    M
 24000  -42.2 -44.0   275   48   25   6.9   3.8   15.8  60.4    17.9      M    M
 23000  -39.7 -39.5   275   45   23   8.9   4.9   15.3  59.6    17.8      M    M
 22000  -37.1 -34.8   275   43   22   8.5   4.7   14.8  58.7    17.6      M    M
 21000  -34.5 -30.1   275   40   21   6.7   3.7   14.4  58.0    17.5      M    M
 20000  -34.0 -29.2   275   37   19   2.3   1.3   11.7  53.0    15.4      M    M
 19500  -33.1 -27.6   275   37   19   8.2   4.5   11.0  51.7    14.9      M    M
 19000  -31.9 -25.4   275   37   19   7.8   4.3   10.6  51.1    14.6      M    M
 18500  -30.7 -23.3   275   36   19   7.7   4.2   10.3  50.5    14.4      M    M
 18000  -29.6 -21.3   275   36   19   6.9   3.8    9.9  49.9    14.2      M    M
 17500  -28.6 -19.5   275   35   18   6.3   3.5    9.3  48.8    13.8      M    M
 17000  -27.7 -17.9   275   32   16   6.2   3.4    8.7  47.7    13.3      M    M
 16500  -26.7 -16.1   275   29   15   7.8   4.3    8.2  46.8    13.0      M    M
 16000  -24.9 -12.8   275   26   13   7.9   4.3    7.8  46.0    12.6      M    M
 15500  -23.7 -10.7   280   25   13   8.0   4.4    7.4  45.4    12.4      M    M
 15000  -22.6  -8.7   280   25   13   6.7   3.7    7.0  44.7    12.1      M    M
 14500  -21.6  -6.9   285   24   13   6.8   3.7    6.5  43.8    11.8      M    M
 14000  -20.6  -5.1   285   24   12   6.8   3.7    6.1  42.9    11.4      M    M
 13500  -19.6  -3.3   290   21   11   6.8   3.7    5.5  42.0    11.0      M    M
 13000  -18.6  -1.5   290   18   10   6.8   3.7    5.0  41.1    10.5      M    M
 12500  -17.6   0.3   295   16    8   6.8   3.7    4.6  40.2    10.2      M    M
 12000  -16.6   2.1   300   14    7   6.8   3.7    4.1  39.4     9.8      M    M
 11500  -15.6   3.9   285   10    5   7.4   4.0    3.6  38.5     9.4      M    M
 11000  -14.4   6.1   265    8    4   7.4   4.0    3.3  38.0     9.1      M    M
 10500  -13.9   7.0   235    7    4 -24.2 -13.3    2.3  36.1     8.2      M    M
 10250  -17.2   1.0   220    8    4 -47.8 -26.2   -2.0  28.4     4.3      M    M
 10000  -19.9  -3.8   205    9    4 -25.7 -14.1   -5.6  21.8     0.8      M    M
  9750  -20.9  -5.6   195   10    5  -0.9  -0.5   -7.5  18.4    -1.0    323  1.6
  9500  -20.4  -4.7   190    9    5  10.3   5.6   -7.7  18.1    -1.1    298  1.5
  9250  -19.8  -3.6   185    9    4   7.3   4.0   -7.8  17.9    -1.2    273  1.4
  9000  -19.2  -2.6   175    8    4   8.3   4.5   -8.0  17.7    -1.4    247  1.3
  8750  -18.6  -1.5   180    7    4   7.5   4.1   -8.1  17.4    -1.5    222  1.1
  8500  -18.0  -0.4   180    6    3   9.7   5.3   -8.2  17.2    -1.7    197  1.0
  8250  -17.4   0.7   185    6    3   1.6   0.9   -8.4  16.9    -1.8    172  0.9
  8000  -17.7   0.1   190    5    3  -4.0  -2.2   -9.4  15.0    -2.8    173  0.9
  7750  -17.6   0.3   190    5    2   4.9   2.7  -10.1  13.8    -3.5    164  0.8
  7500  -17.1   1.2   195    4    2   7.4   4.1  -10.4  13.4    -3.8    142  0.7
  7250  -16.6   2.1   195    4    2   6.7   3.7  -10.6  13.0    -4.0    119  0.6
  7000  -16.1   3.0   200    4    2   7.0   3.8  -10.8  12.6    -4.2     96  0.5
  6750  -15.6   3.9   195    4    2   6.7   3.7  -11.0  12.2    -4.4     73  0.4
  6500  -15.1   4.8   185    3    2   6.4   3.5  -11.3  11.7    -4.7     51  0.3
  6250  -14.6   5.7   175    3    2   6.5   3.5  -11.5  11.3    -5.0     29  0.1
  6000  -14.1   6.6   165    3    2   6.3   3.4  -11.8  10.8    -5.2      7  0.0
  5750  -13.6   7.5   150    3    2   7.0   3.9  -12.0  10.4    -5.5      M    M
  5500  -13.3   8.1   135    3    2  -2.4  -1.3  -12.4   9.6    -5.9      M    M

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

           02/27/2015 at 0800 MST          |       02/27/2015 at 1100 MST
                                           |
K index... +5.3  LI... +277.8              | K index... +4.4  LI... +277.1
CAPE... 0.0  CIN... M                      | 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 -53.1 -63.6  290  42 22   1.4   0.7 | -53.0 -63.4  285  43 22   1.1   0.6
 45000 -51.0 -59.8  290  40 21   1.4   0.7 | -51.2 -60.2  280  42 21   1.1   0.6
 40000 -50.4 -58.7  290  40 21   0.2   0.1 | -50.8 -59.4  285  40 21   0.1   0.0
 38000 -50.2 -58.4  290  40 21   0.6   0.4 | -50.8 -59.4  285  39 20   0.3   0.2
 36000 -52.2 -62.0  290  40 21  -3.7  -2.0 | -52.8 -63.0  290  38 19  -3.7  -2.0
 34000 -54.4 -65.9  290  40 21  -3.7  -2.0 | -55.0 -67.0  290  36 19  -3.7  -2.0
 32000 -54.6 -66.3  290  39 20   2.7   1.5 | -55.0 -67.0  300  32 17   3.2   1.8
 30000 -53.0 -63.4  290  37 19   2.7   1.5 | -53.0 -63.4  310  28 15   3.3   1.8
 29000 -51.8 -61.2  290  36 19   7.0   3.9 | -51.5 -60.7  315  27 14   8.1   4.4
 28000 -49.7 -57.5  290  36 19   6.7   3.7 | -49.2 -56.6  315  27 14   7.9   4.3
 27000 -47.7 -53.9  290  36 19   6.7   3.7 | -46.8 -52.2  315  28 14   7.8   4.3
 26000 -45.7 -50.3  295  36 19   6.9   3.8 | -44.5 -48.1  320  28 14   7.3   4.0
 25000 -43.5 -46.3  295  37 19   7.2   4.0 | -42.5 -44.5  315  27 14   6.7   3.7
 24000 -41.4 -42.5  295  37 19   7.2   4.0 | -40.5 -40.9  310  26 14   6.7   3.6
 23000 -39.2 -38.6  295  37 19   6.9   3.8 | -38.5 -37.3  305  26 13   6.7   3.7
 22000 -37.3 -35.1  290  37 19   6.4   3.5 | -36.5 -33.7  300  27 14   6.7   3.7
 21000 -35.3 -31.5  285  37 19   6.4   3.5 | -34.5 -30.1  300  28 14   6.7   3.7
 20000 -33.4 -28.1  280  37 19   7.3   4.0 | -32.5 -26.5  295  29 15   6.1   3.4
 19500 -32.3 -26.1  280  36 19   7.2   4.0 | -31.6 -24.9  290  30 15   6.2   3.4
 19000 -31.2 -24.2  275  36 18   7.2   4.0 | -30.6 -23.1  285  31 16   6.2   3.4
 18500 -30.1 -22.2  270  35 18   7.2   4.0 | -29.7 -21.5  285  32 16   6.3   3.4
 18000 -29.1 -20.4  270  35 18   7.2   3.9 | -28.8 -19.8  280  33 17   6.2   3.4
 17500 -27.9 -18.2  265  33 17   8.1   4.5 | -27.8 -18.0  280  34 17   7.6   4.1
 17000 -26.1 -15.0  270  29 15   7.9   4.3 | -26.1 -15.0  275  34 18   7.4   4.1
 16500 -25.1 -13.2  270  27 14   6.4   3.5 | -25.0 -13.0  275  34 17   7.1   3.9
 16000 -24.1 -11.4  275  25 13   6.4   3.5 | -23.9 -11.0  275  32 17   7.2   3.9
 15500 -23.1  -9.6  275  24 12   6.9   3.8 | -22.9  -9.2  275  31 16   7.1   3.9
 15000 -22.1  -7.8  280  23 12   6.9   3.8 | -21.8  -7.2  275  29 15   7.1   3.9
 14500 -21.1  -6.0  290  22 11   7.1   3.9 | -20.7  -5.3  280  28 14   7.9   4.3
 14000 -20.0  -4.0  295  21 11   7.1   3.9 | -19.5  -3.1  280  27 14   8.1   4.4
 13500 -19.0  -2.2  300  20 10   6.7   3.7 | -18.3  -0.9  285  26 13   7.2   4.0
 13000 -18.0  -0.4  300  18  9   6.5   3.6 | -17.3   0.9  290  24 12   6.9   3.8
 12500 -17.1   1.2  305  16  8   6.1   3.3 | -16.3   2.7  290  23 12   6.2   3.4
 12000 -16.2   2.8  305  14  7   5.9   3.3 | -15.5   4.1  295  20 11   5.9   3.2
 11500 -15.4   4.3  300  13  6   3.5   1.9 | -14.6   5.7  295  18  9   4.7   2.6
 11000 -15.0   5.0  295  10  5   2.7   1.5 | -14.0   6.8  295  15  8   4.4   2.4
 10500 -14.8   5.4  290   8  4   0.6   0.3 | -13.5   7.7  295  13  7   2.0   1.1
 10250 -14.8   5.4  285   8  4   0.0   0.0 | -13.4   7.9  295  11  6   1.3   0.7
 10000 -14.7   5.5  275   7  4   0.3   0.2 | -13.3   8.1  295  10  5   1.7   0.9
  9750 -14.7   5.5  265   6  3  -0.3  -0.1 | -13.2   8.2  295   9  4   0.7   0.4
  9500 -14.8   5.4  260   6  3  -2.1  -1.2 | -13.2   8.2  290   7  4  -0.7  -0.4
  9250 -15.0   5.0  250   5  3  -3.0  -1.7 | -13.2   8.2  290   7  3  -0.8  -0.4
  9000 -15.2   4.6  235   5  3  -2.7  -1.5 | -13.3   8.1  285   6  3  -0.8  -0.5
  8750 -15.4   4.3  230   5  3  -2.2  -1.2 | -13.4   7.9  280   5  2  -3.3  -1.8
  8500 -15.6   3.9  230   5  2  -1.4  -0.8 | -13.8   7.2  275   4  2  -5.0  -2.7
  8250 -15.7   3.7  235   5  2  -2.5  -1.4 | -14.1   6.6  265   4  2  -5.1  -2.8
  8000 -15.8   3.6  235   5  2   1.6   0.9 | -14.5   5.9  250   3  2  -3.1  -1.7
  7750 -15.4   4.3  215   7  4   6.1   3.4 | -14.5   5.9  235   3  2   1.8   1.0
  7500 -15.0   5.0  200  10  5   5.7   3.1 | -14.2   6.4  210   3  2   4.7   2.6
  7250 -14.6   5.7  195  14  7   4.9   2.7 | -13.9   7.0  190   5  2   5.5   3.0
  7000 -14.3   6.3  190  16  8   2.8   1.5 | -13.4   7.9  175   6  3   5.6   3.1
  6750 -14.1   6.6  185  16  8   2.6   1.4 | -13.0   8.6  170   7  3   6.4   3.5
  6500 -13.9   7.0  180  16  8   4.3   2.4 | -12.5   9.5  165   7  4   7.6   4.2
  6250 -13.4   7.9  180  15  8   7.4   4.0 | -11.9  10.6  165   7  4   9.5   5.2
  6000 -12.8   9.0  175  13  7   9.0   5.0 | -11.1  12.0  165   7  3  10.9   6.0
  5750 -12.2  10.0  175  11  6   8.0   4.4 | -10.3  13.5  165   6  3   9.7   5.3
  5500 -11.6  11.1  170   9  5   8.3   4.6 |  -9.6  14.7  165   6  3  11.2   6.1

           02/27/2015 at 1400 MST          |       02/27/2015 at 1700 MST
                                           |
K index... +6.0  LI... +277.5              | K index... +8.2  LI... +277.5
CAPE... 0.0  CIN... -0.5                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -53.0 -63.4  280  44 23   1.0   0.6 | -53.4 -64.1  280  47 24   1.0   0.6
 45000 -51.5 -60.7  280  43 22   1.0   0.6 | -51.9 -61.4  275  47 24   1.0   0.5
 40000 -51.2 -60.2  280  44 23   0.0   0.0 | -51.4 -60.5  275  46 24   0.1   0.1
 38000 -51.2 -60.2  280  45 23   0.2   0.1 | -51.3 -60.3  280  46 24   0.1   0.0
 36000 -53.2 -63.8  285  42 21  -3.7  -2.0 | -53.5 -64.3  280  43 22  -3.9  -2.2
 34000 -55.7 -68.3  290  38 20  -3.8  -2.1 | -55.8 -68.4  280  39 20  -3.9  -2.2
 32000 -55.5 -67.9  290  33 17   2.8   1.5 | -55.8 -68.4  280  36 19   3.2   1.7
 30000 -53.8 -64.8  295  27 14   2.9   1.6 | -53.8 -64.8  280  35 18   3.3   1.8
 29000 -52.2 -62.0  300  26 13   9.0   4.9 | -52.1 -61.8  280  33 17   8.8   4.8
 28000 -49.5 -57.1  310  25 13   8.8   4.9 | -49.5 -57.1  285  29 15   8.8   4.8
 27000 -46.9 -52.4  315  26 13   8.8   4.9 | -46.9 -52.4  290  26 13   8.8   4.8
 26000 -44.2 -47.6  325  26 14   8.8   4.8 | -44.2 -47.6  295  22 12   8.6   4.7
 25000 -41.6 -42.9  325  26 14   8.7   4.8 | -41.7 -43.1  295  21 11   8.5   4.7
 24000 -39.0 -38.2  330  26 14   8.7   4.8 | -39.1 -38.4  300  19 10   8.6   4.7
 23000 -36.4 -33.5  335  26 14   7.2   3.9 | -36.6 -33.9  300  17  9   7.4   4.1
 22000 -34.6 -30.3  320  23 12   5.8   3.2 | -34.5 -30.1  285  18  9   6.7   3.7
 21000 -32.9 -27.2  305  20 10   5.8   3.2 | -32.5 -26.5  275  21 11   6.7   3.7
 20000 -31.1 -24.0  290  20 10   5.7   3.1 | -30.6 -23.1  270  24 12   5.6   3.1
 19500 -30.3 -22.5  290  22 11   5.7   3.1 | -29.7 -21.5  270  25 13   5.7   3.1
 19000 -29.4 -20.9  290  23 12   5.7   3.1 | -28.9 -20.0  275  26 13   5.7   3.1
 18500 -28.6 -19.5  290  25 13   5.7   3.1 | -28.0 -18.4  280  27 14   5.7   3.1
 18000 -27.7 -17.9  290  26 14   5.7   3.1 | -27.2 -17.0  280  29 15   5.7   3.2
 17500 -26.8 -16.2  290  29 15   6.5   3.6 | -26.3 -15.3  280  30 16   6.3   3.4
 17000 -25.4 -13.7  285  34 18   6.6   3.6 | -24.9 -12.8  275  33 17   6.4   3.5
 16500 -24.5 -12.1  280  37 19   6.5   3.6 | -23.9 -11.0  275  33 17   7.0   3.8
 16000 -23.5 -10.3  280  38 20   6.5   3.5 | -22.9  -9.2  275  33 17   6.9   3.8
 15500 -22.5  -8.5  280  38 20   7.7   4.2 | -21.8  -7.2  275  32 16   7.9   4.3
 15000 -21.3  -6.3  280  37 19   7.7   4.2 | -20.6  -5.1  275  30 15   7.9   4.3
 14500 -20.2  -4.4  280  35 18   7.3   4.0 | -19.5  -3.1  280  28 14   6.8   3.7
 14000 -19.1  -2.4  280  33 17   7.2   3.9 | -18.5  -1.3  285  26 13   6.7   3.7
 13500 -18.1  -0.6  285  31 16   7.1   3.9 | -17.6   0.3  285  24 13   6.9   3.8
 13000 -17.0   1.4  285  29 15   7.1   3.9 | -16.5   2.3  290  22 11   7.0   3.8
 12500 -16.0   3.2  290  27 14   6.3   3.4 | -15.5   4.1  295  20 10   6.3   3.4
 12000 -15.1   4.8  290  23 12   5.8   3.2 | -14.6   5.7  295  17  9   5.9   3.3
 11500 -14.3   6.3  295  19 10   4.9   2.7 | -13.8   7.2  295  14  7   5.1   2.8
 11000 -13.6   7.5  295  16  8   4.6   2.5 | -13.1   8.4  295  11  6   4.8   2.6
 10500 -13.0   8.6  295  12  6   2.8   1.6 | -12.4   9.7  290   9  4   4.0   2.2
 10250 -12.8   9.0  290  11  6   2.2   1.2 | -12.1  10.2  290   8  4   3.7   2.0
 10000 -12.7   9.1  290  10  5   2.6   1.4 | -11.8  10.8  285   7  3   4.0   2.2
  9750 -12.5   9.5  285   8  4   3.0   1.7 | -11.6  11.1  280   6  3   3.6   2.0
  9500 -12.3   9.9  285   7  4   2.1   1.1 | -11.3  11.7  280   5  3   2.5   1.4
  9250 -12.1  10.2  285   6  3   1.1   0.6 | -11.1  12.0  280   4  2   2.3   1.3
  9000 -12.0  10.4  280   6  3   1.9   1.0 | -11.0  12.2  280   4  2   2.4   1.3
  8750 -11.9  10.6  275   5  2  -0.6  -0.3 | -10.9  12.4  280   3  2  -2.0  -1.1
  8500 -12.1  10.2  275   4  2  -3.6  -2.0 | -11.2  11.8  275   3  1  -4.8  -2.7
  8250 -12.4   9.7  270   3  2  -3.7  -2.0 | -11.5  11.3  270   2  1  -3.8  -2.1
  8000 -12.7   9.1  265   2  1  -2.9  -1.6 | -11.8  10.8  255   2  1  -4.0  -2.2
  7750 -12.8   9.0  210   2  1   0.2   0.1 | -12.0  10.4  215   2  1  -0.2  -0.1
  7500 -12.7   9.1  165   2  1   2.1   1.2 | -11.9  10.6  185   3  1   3.2   1.8
  7250 -12.5   9.5  150   4  2   3.3   1.8 | -11.6  11.1  175   4  2   4.0   2.2
  7000 -12.1  10.2  145   4  2   7.9   4.3 | -11.2  11.8  170   5  2   7.4   4.1
  6750 -11.4  11.5  140   4  2  10.0   5.5 | -10.6  12.9  165   5  2   9.1   5.0
  6500 -10.7  12.7  140   4  2   9.0   4.9 | -10.0  14.0  160   4  2   8.2   4.5
  6250 -10.0  14.0  140   4  2   9.8   5.4 |  -9.3  15.3  155   4  2   9.1   5.0
  6000  -9.3  15.3  140   4  2  10.5   5.8 |  -8.6  16.5  150   3  2  10.0   5.5
  5750  -8.5  16.7  140   3  2   9.9   5.4 |  -7.9  17.8  145   2  1   9.4   5.2
  5500  -7.7  18.1  135   3  2  11.2   6.1 |  -7.2  19.0  130   2  1   8.5   4.6
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

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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