Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 211216
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0516 MST Saturday, February 21, 2015

This forecast is for Saturday, February 21, 2015:

If the trigger temperature of 38.4 F/3.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5944 ft MSL (659 ft AGL)

Forecast maximum temperature................... 31.0 F/-1.0 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Sunday 02/22....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Snow
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 18093 ft MSL (12808 ft AGL)
Wave soaring outlook for Sunday 02/22.......... Poor

Remarks...

Sunrise/Sunset.................... 06:44:08 / 17:41:13 MST
Total possible sunshine........... 10 hr 57 min 5 sec (657 min 5 sec)
Altitude of sun at 12:12:58 MST... 39.80 degrees

Upper air data from rawinsonde observation taken on 02/21/2015 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 9409 ft MSL (4124 ft AGL)
Lifted condensation level....... 7748 ft MSL (2463 ft AGL)
Lifted index.................... +8.6
K index......................... +15.0

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  -51.6 -60.9   285   50   26  -0.8  -0.5  118.3 245.0    67.3      M    M
 45000  -54.5 -66.1   275   59   30  -1.7  -1.0   87.2 189.0    53.3      M    M
 40000  -50.2 -58.4   275   71   36  -2.7  -1.5   70.9 159.5    46.3      M    M
 38000  -50.3 -58.5   270   71   36   3.4   1.9   61.7 143.1    41.4      M    M
 36000  -50.7 -59.3   275   66   34   0.5   0.3   52.5 126.5    36.3      M    M
 34000  -52.8 -63.0   275   79   41   2.8   1.5   40.9 105.6    29.1      M    M
 32000  -52.3 -62.1   270   88   45   0.0   0.0   32.3  90.2    23.8      M    M
 30000  -52.3 -62.1   270   77   40   1.9   1.0   24.4  76.0    18.6      M    M
 29000  -50.2 -58.4   270   79   41   8.0   4.4   23.3  74.8    18.0      M    M
 28000  -47.9 -54.2   275   80   41   6.8   3.8   22.6  72.6    17.6      M    M
 27000  -46.2 -51.2   275   82   42   6.3   3.5   20.9  69.6    16.5      M    M
 26000  -44.4 -47.9   280   84   43   6.9   3.8   19.4  67.0    15.6      M    M
 25000  -42.1 -43.8   285   72   37   5.8   3.2   18.6  65.5    15.2      M    M
 24000  -39.5 -39.1   285   57   30  10.4   5.7   18.3  64.9    15.1      M    M
 23000  -39.0 -38.2   280   38   20  -2.5  -1.4   15.2  59.4    12.8      M    M
 22000  -38.0 -36.4   270   32   17   7.7   4.2   12.9  55.2    11.1      M    M
 21000  -36.0 -32.8   285   30   15   8.8   4.8   11.8  53.2    10.2      M    M
 20000  -33.5 -28.3   270   23   12   8.4   4.6   11.3  52.3     9.9      M    M
 19500  -32.3 -26.1   275   24   13   8.3   4.6   11.0  51.8     9.8      M    M
 19000  -31.0 -23.8   275   26   13   8.5   4.7   10.8  51.4     9.6      M    M
 18500  -29.7 -21.5   280   28   14   8.6   4.7   10.6  51.0     9.5      M    M
 18000  -28.4 -19.1   280   30   15   9.0   4.9   10.4  50.7     9.4      M    M
 17500  -27.0 -16.6   280   31   16   9.6   5.3   10.3  50.6     9.4      M    M
 17000  -25.7 -14.3   280   29   15   7.9   4.3   10.1  50.3     9.3      M    M
 16500  -24.5 -12.1   280   27   14   8.0   4.4    9.8  49.7     9.0      M    M
 16000  -23.3  -9.9   280   25   13   8.0   4.4    9.6  49.2     8.8      M    M
 15500  -21.5  -6.7   280   22   11   8.1   4.4    9.1  48.4     8.5      M    M
 15000  -20.4  -4.7   285   20   10   7.9   4.3    8.8  47.9     8.3      M    M
 14500  -19.2  -2.6   285   18    9   7.3   4.0    8.5  47.2     8.0      M    M
 14000  -18.2  -0.8   290   16    8   7.3   4.0    8.1  46.5     7.6      M    M
 13500  -17.2   1.0   295   16    8   6.1   3.3    7.6  45.6     7.2      M    M
 13000  -16.2   2.8   295   15    8   8.3   4.6    7.1  44.8     6.8      M    M
 12500  -14.9   5.2   285   12    6   8.5   4.7    6.9  44.5     6.7      M    M
 12000  -13.6   7.5   275   10    5   7.0   3.8    6.8  44.2     6.5      M    M
 11500  -12.9   8.8   270    8    4   4.8   2.6    6.0  42.7     5.8      M    M
 11000  -12.1  10.2   260    6    3   6.9   3.8    5.3  41.5     5.1      M    M
 10500  -11.0  12.2   245    5    3   7.6   4.2    4.9  40.8     4.8      M    M
 10250  -10.4  13.3   230    4    2   7.7   4.2    4.8  40.6     4.7      M    M
 10000   -9.8  14.4   220    4    2   7.6   4.1    4.6  40.3     4.5      M    M
  9750   -9.3  15.3   210    4    2   6.9   3.8    4.4  39.9     4.3      M    M
  9500   -8.8  16.2   210    3    1   6.5   3.6    4.1  39.5     4.1      M    M
  9250   -8.3  17.1   205    2    1   6.6   3.6    3.9  39.0     3.9      M    M
  9000   -7.9  17.8   195    1    0   6.7   3.7    3.7  38.6     3.6      M    M
  8750   -7.3  18.9   000    0    0   6.3   3.5    3.4  38.1     3.4      M    M
  8500   -6.9  19.6   030    2    1   5.3   2.9    3.1  37.6     3.1      M    M
  8250   -6.6  20.1   025    3    1   4.9   2.7    2.7  36.9     2.7      M    M
  8000   -6.2  20.8   025    4    2   5.0   2.7    2.4  36.2     2.4      M    M
  7750   -5.9  21.4   045    3    2   5.0   2.7    2.0  35.6     2.0      M    M
  7500   -5.5  22.1   070    3    1   5.0   2.8    1.6  34.9     1.6      M    M
  7250   -5.1  22.8   100    3    2   4.8   2.6    1.2  34.2     1.3      M    M
  7000   -4.8  23.4   120    4    2   5.8   3.2    0.9  33.6     0.9      M    M
  6750   -4.3  24.3   115    4    2   7.2   3.9    0.6  33.2     0.6      M    M
  6500   -3.8  25.2   115    4    2   7.2   3.9    0.4  32.8     0.4      M    M
  6250   -3.2  26.2   110    4    2   7.2   3.9    0.2  32.4     0.3      M    M
  6000   -2.7  27.1   105    4    2   7.2   3.9    0.1  32.1     0.1      M    M
  5750   -2.2  28.0   115    4    2   7.2   3.9   -0.1  31.8    -0.1      M    M
  5500   -1.6  29.1   120    4    2   6.7   3.7   -0.3  31.4    -0.4      M    M

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

           02/21/2015 at 0800 MST          |       02/21/2015 at 1100 MST
                                           |
K index... +18.6  LI... +274.6             | K index... +20.5  LI... +273.5
CAPE... 0.0  CIN... 0.0                    | CAPE... +40.0  CIN... -1.2
                                           |
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 -54.0 -65.2  290  49 25   1.9   1.0 | -53.9 -65.0  295  45 23   1.2   0.7
 45000 -51.2 -60.2  285  49 25   1.9   1.0 | -52.0 -61.6  290  50 26   1.2   0.7
 40000 -50.8 -59.4  280  57 29  -0.1  -0.1 | -50.7 -59.3  285  58 30   0.8   0.4
 38000 -50.9 -59.6  275  60 31  -0.6  -0.3 | -50.3 -58.5  280  62 32  -0.1  -0.1
 36000 -51.4 -60.5  275  65 33  -0.9  -0.5 | -50.6 -59.1  280  64 33  -0.6  -0.3
 34000 -51.9 -61.4  275  69 35  -0.9  -0.5 | -51.0 -59.8  275  66 34  -0.6  -0.3
 32000 -51.9 -61.4  275  70 36   0.6   0.3 | -51.1 -60.0  275  65 34  -0.2  -0.1
 30000 -51.6 -60.9  275  70 36   0.6   0.3 | -51.2 -60.2  275  63 32  -0.2  -0.1
 29000 -50.7 -59.3  275  68 35   4.7   2.6 | -50.7 -59.3  275  60 31   3.5   1.9
 28000 -49.3 -56.7  275  64 33   4.8   2.6 | -49.6 -57.3  275  57 29   3.7   2.0
 27000 -47.8 -54.0  280  60 31   4.8   2.6 | -48.5 -55.3  275  53 27   3.7   2.0
 26000 -46.3 -51.3  280  56 29   6.9   3.8 | -47.3 -53.1  275  49 25   6.9   3.8
 25000 -44.1 -47.4  280  48 25   7.1   3.9 | -45.1 -49.2  275  43 22   7.4   4.1
 24000 -42.0 -43.6  280  41 21   7.1   3.9 | -42.9 -45.2  270  37 19   7.4   4.1
 23000 -39.9 -39.8  280  34 17   7.3   4.0 | -40.6 -41.1  265  32 16   8.7   4.7
 22000 -37.7 -35.9  280  31 16   7.3   4.0 | -38.0 -36.4  265  28 14   8.8   4.8
 21000 -35.5 -31.9  280  28 14   7.3   4.0 | -35.3 -31.5  265  24 12   8.8   4.8
 20000 -33.1 -27.6  280  26 13   9.1   5.0 | -32.8 -27.0  270  21 11   8.2   4.5
 19500 -31.8 -25.2  285  25 13   9.1   5.0 | -31.6 -24.9  270  21 11   8.2   4.5
 19000 -30.4 -22.7  285  25 13   9.1   5.0 | -30.3 -22.5  275  21 11   8.2   4.5
 18500 -29.0 -20.2  285  25 13   9.1   5.0 | -29.1 -20.4  280  20 10   8.3   4.5
 18000 -27.7 -17.9  285  24 13   9.1   5.0 | -27.9 -18.2  285  20 10   8.3   4.5
 17500 -26.4 -15.5  285  23 12   8.9   4.9 | -26.7 -16.1  285  19 10   8.3   4.6
 17000 -25.0 -13.0  285  22 11   9.0   4.9 | -25.4 -13.7  280  18  9   8.4   4.6
 16500 -23.8 -10.8  280  21 11   7.8   4.3 | -24.2 -11.6  280  17  9   7.8   4.3
 16000 -22.6  -8.7  280  20 10   8.0   4.4 | -23.1  -9.6  280  16  8   7.9   4.3
 15500 -21.0  -5.8  275  18  9   7.1   3.9 | -21.9  -7.4  275  15  8   7.2   4.0
 15000 -19.9  -3.8  270  16  8   7.2   3.9 | -20.4  -4.7  265  12  6   7.1   3.9
 14500 -18.9  -2.0  260  15  8   6.9   3.8 | -19.3  -2.7  255  11  6   7.6   4.2
 14000 -17.9  -0.2  255  14  7   7.0   3.8 | -18.2  -0.8  245  10  5   7.5   4.1
 13500 -16.9   1.6  245  12  6   6.7   3.7 | -17.1   1.2  235   9  5   7.6   4.2
 13000 -15.9   3.4  235  11  6   6.8   3.7 | -15.9   3.4  225   9  4   7.6   4.2
 12500 -14.9   5.2  225  10  5   5.7   3.1 | -14.9   5.2  215   8  4   7.0   3.8
 12000 -14.1   6.6  215   8  4   5.6   3.1 | -13.8   7.2  210   8  4   7.0   3.8
 11500 -13.2   8.2  205   7  4   7.3   4.0 | -12.8   9.0  200   7  4   7.5   4.1
 11000 -12.1  10.2  200   6  3   7.3   4.0 | -11.7  10.9  195   7  4   7.7   4.2
 10500 -11.1  12.0  195   5  3   6.2   3.4 | -10.7  12.7  185   7  4   5.8   3.2
 10250 -10.7  12.7  190   5  3   5.8   3.2 | -10.3  13.5  185   7  4   5.4   2.9
 10000 -10.2  13.6  185   5  3   7.7   4.3 |  -9.8  14.4  180   7  4   8.0   4.4
  9750  -9.6  14.7  180   5  3   7.8   4.3 |  -9.2  15.4  175   7  4   8.2   4.5
  9500  -9.1  15.6  175   5  2   5.8   3.2 |  -8.7  16.3  170   7  4   5.7   3.1
  9250  -8.7  16.3  165   5  2   6.4   3.5 |  -8.2  17.2  165   7  4   6.3   3.5
  9000  -8.2  17.2  160   5  2   6.3   3.4 |  -7.8  18.0  160   7  4   6.4   3.5
  8750  -7.7  18.1  155   5  3   6.7   3.7 |  -7.3  18.9  155   7  4   6.5   3.6
  8500  -7.2  19.0  150   5  3   7.0   3.9 |  -6.8  19.8  150   7  4   6.4   3.5
  8250  -6.7  19.9  145   6  3   6.8   3.8 |  -6.4  20.5  145   7  4   6.3   3.5
  8000  -6.2  20.8  140   6  3   7.6   4.2 |  -5.9  21.4  135   8  4   6.8   3.7
  7750  -5.7  21.7  140   7  3   7.3   4.0 |  -5.4  22.3  115   9  5   6.6   3.6
  7500  -5.2  22.6  135   7  4   6.5   3.6 |  -5.0  23.0  105  10  5   5.8   3.2
  7250  -4.7  23.5  130   8  4   6.4   3.5 |  -4.5  23.9  100  12  6   6.6   3.6
  7000  -4.3  24.3  120   8  4   6.3   3.5 |  -4.0  24.8  090  12  6   8.0   4.4
  6750  -3.8  25.2  110   9  4   5.0   2.7 |  -3.4  25.9  085  12  6   7.9   4.4
  6500  -3.5  25.7  100   9  5   3.9   2.1 |  -2.9  26.8  075  12  6   7.7   4.2
  6250  -3.2  26.2  095   9  4   6.1   3.3 |  -2.3  27.9  070  11  6   9.4   5.1
  6000  -2.7  27.1  085   7  4   7.2   3.9 |  -1.5  29.3  070  10  5  10.7   5.9
  5750  -2.2  28.0  070   6  3   6.8   3.7 |  -0.8  30.6  065   9  5   9.4   5.1
  5500  -1.6  29.1  055   5  2   9.4   5.1 |  -0.1  31.8  060   8  4  10.4   5.7

           02/21/2015 at 1400 MST          |       02/21/2015 at 1700 MST
                                           |
K index... +19.4  LI... +274.2             | K index... +18.9  LI... +274.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -3.4
                                           |
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 -53.6 -64.5  290  50 26   1.1   0.6 | -54.3 -65.7  290  47 24   1.8   1.0
 45000 -51.9 -61.4  285  54 28   1.1   0.6 | -51.4 -60.5  285  51 26   1.8   1.0
 40000 -50.0 -58.0  285  61 31   1.3   0.7 | -50.4 -58.7  285  61 31   0.5   0.3
 38000 -49.2 -56.6  285  64 33  -0.3  -0.2 | -50.1 -58.2  285  65 33  -0.7  -0.4
 36000 -50.1 -58.2  280  67 35  -1.4  -0.8 | -51.0 -59.8  280  72 37  -1.5  -0.8
 34000 -50.9 -59.6  280  70 36  -1.4  -0.8 | -51.9 -61.4  280  79 41  -1.5  -0.8
 32000 -51.4 -60.5  280  69 35  -0.3  -0.2 | -51.7 -61.1  280  79 41   1.6   0.9
 30000 -51.6 -60.9  275  64 33  -0.2  -0.1 | -50.6 -59.1  280  73 38   1.6   0.9
 29000 -51.1 -60.0  275  60 31   3.7   2.0 | -49.9 -57.8  275  68 35   3.1   1.7
 28000 -49.9 -57.8  275  53 27   3.8   2.1 | -49.0 -56.2  275  59 30   3.1   1.7
 27000 -48.8 -55.8  270  47 24   3.8   2.1 | -48.1 -54.6  270  51 26   3.1   1.7
 26000 -47.4 -53.3  265  41 21   7.5   4.1 | -46.9 -52.4  270  43 22   6.8   3.7
 25000 -45.0 -49.0  260  35 18   8.2   4.5 | -44.7 -48.5  265  36 19   7.5   4.1
 24000 -42.5 -44.5  255  28 15   8.2   4.5 | -42.5 -44.5  260  30 15   7.5   4.1
 23000 -40.1 -40.2  245  23 12   8.3   4.6 | -40.2 -40.4  250  24 12   8.5   4.6
 22000 -37.6 -35.7  250  19 10   8.3   4.6 | -37.6 -35.7  255  22 11   8.6   4.7
 21000 -35.1 -31.2  260  16  8   8.3   4.6 | -35.0 -31.0  265  20 10   8.6   4.7
 20000 -32.6 -26.7  270  14  7   8.4   4.6 | -32.5 -26.5  270  18  9   8.4   4.6
 19500 -31.3 -24.3  270  14  7   8.4   4.6 | -31.2 -24.2  270  18  9   8.4   4.6
 19000 -30.1 -22.2  275  13  7   8.5   4.6 | -30.0 -22.0  275  17  9   8.5   4.6
 18500 -28.8 -19.8  280  13  7   8.4   4.6 | -28.7 -19.7  275  17  9   8.4   4.6
 18000 -27.5 -17.5  285  13  6   8.2   4.5 | -27.4 -17.3  280  16  8   8.3   4.5
 17500 -26.4 -15.5  285  12  6   7.8   4.3 | -26.3 -15.3  280  16  8   7.9   4.3
 17000 -25.2 -13.4  285  12  6   7.8   4.3 | -25.1 -13.2  285  16  8   7.9   4.4
 16500 -24.1 -11.4  285  11  6   7.6   4.1 | -23.9 -11.0  285  15  7   7.3   4.0
 16000 -22.4  -8.3  280   9  5   7.6   4.2 | -22.3  -8.1  280  12  6   7.3   4.0
 15500 -21.3  -6.3  275   9  4   7.6   4.2 | -21.3  -6.3  280  11  5   6.9   3.8
 15000 -20.2  -4.4  270   8  4   7.6   4.2 | -20.2  -4.4  280   9  5   7.0   3.8
 14500 -19.0  -2.2  265   7  4   7.8   4.3 | -19.2  -2.6  280   7  4   7.4   4.1
 14000 -17.9  -0.2  255   6  3   7.8   4.3 | -18.1  -0.6  285   6  3   7.3   4.0
 13500 -16.8   1.8  245   6  3   7.5   4.1 | -16.9   1.6  285   4  2   8.1   4.5
 13000 -15.7   3.7  235   5  3   7.6   4.2 | -15.8   3.6  280   3  1   8.2   4.5
 12500 -14.6   5.7  215   4  2   7.1   3.9 | -14.6   5.7  260   2  1   6.9   3.8
 12000 -13.5   7.7  200   4  2   7.1   3.9 | -13.6   7.5  195   1  1   7.0   3.8
 11500 -12.5   9.5  180   5  2   7.0   3.8 | -12.6   9.3  155   2  1   6.5   3.6
 11000 -11.5  11.3  160   5  3   7.1   3.9 | -11.7  10.9  140   4  2   6.7   3.7
 10500 -10.5  13.1  150   6  3   6.0   3.3 | -10.8  12.6  135   6  3   5.4   3.0
 10250 -10.1  13.8  145   7  3   5.4   3.0 | -10.4  13.3  130   7  3   4.8   2.6
 10000  -9.7  14.5  140   7  4   8.2   4.5 | -10.0  14.0  125   8  4   7.7   4.2
  9750  -9.0  15.8  135   8  4   8.2   4.5 |  -9.4  15.1  120   9  5   8.0   4.4
  9500  -8.5  16.7  130   9  5   5.4   3.0 |  -8.9  16.0  115  10  5   5.3   2.9
  9250  -8.1  17.4  125  10  5   6.2   3.4 |  -8.5  16.7  110  10  5   5.9   3.2
  9000  -7.6  18.3  120  11  6   5.8   3.2 |  -8.1  17.4  105  11  6   6.1   3.3
  8750  -7.2  19.0  115  11  6   5.8   3.2 |  -7.6  18.3  100  12  6   5.5   3.0
  8500  -6.8  19.8  110  13  6   6.1   3.3 |  -7.3  18.9  095  13  7   4.6   2.5
  8250  -6.4  20.5  105  14  7   5.8   3.2 |  -6.9  19.6  090  14  7   4.9   2.7
  8000  -5.9  21.4  100  15  8   6.8   3.7 |  -6.6  20.1  090  15  8   4.7   2.6
  7750  -5.4  22.3  095  15  8   5.9   3.2 |  -6.2  20.8  080  16  8   4.7   2.6
  7500  -5.1  22.8  090  15  8   4.1   2.3 |  -5.9  21.4  075  16  8   4.3   2.4
  7250  -4.7  23.5  080  15  8   5.2   2.9 |  -5.6  21.9  070  17  9   5.5   3.0
  7000  -4.3  24.3  075  15  8   6.2   3.4 |  -5.1  22.8  060  17  9   7.6   4.2
  6750  -3.8  25.2  065  15  8   6.9   3.8 |  -4.5  23.9  055  16  8   7.3   4.0
  6500  -3.3  26.1  060  15  8   7.4   4.1 |  -4.0  24.8  050  16  8   6.9   3.8
  6250  -2.8  27.0  050  15  8   9.0   4.9 |  -3.5  25.7  045  15  8   8.6   4.7
  6000  -2.0  28.4  050  14  7  10.2   5.6 |  -2.8  27.0  040  14  7   9.9   5.4
  5750  -1.3  29.7  045  12  6   9.4   5.2 |  -2.1  28.2  035  13  6   8.6   4.7
  5500  -0.7  30.7  040  11  6  10.3   5.7 |  -1.5  29.3  030  11  6   8.0   4.4
________________________________________________________________________________

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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