Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 041317
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0617 MST Wednesday, March 4, 2015

This forecast is for Wednesday, March 4, 2015:

If the trigger temperature of 21.7 F/-5.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 178 ft/min (0.9 m/s)
   Maximum height of thermals.................. 8091 ft MSL (2784 ft AGL)

Forecast maximum temperature................... 19.0 F/-7.7 C
Time of trigger temperature.................... None
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................. None
Thermal soaring outlook for Thursday 03/05..... Fair

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Becoming fair
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 26968 ft MSL (21661 ft AGL)
Wave soaring outlook for Thursday 03/05........ Poor

Remarks... Snow decreasing to isolated showers

Sunrise/Sunset.................... 06:28:16 / 17:53:27 MST
Total possible sunshine........... 11 hr 25 min 11 sec (685 min 11 sec)
Altitude of sun at 12:11:05 MST... 43.91 degrees

Upper air data from numerical model forecast valid on 03/04/2015 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 7956 ft MSL (2649 ft AGL)
Lifted condensation level....... 7989 ft MSL (2683 ft AGL)
Lifted index.................... +16.6
K index......................... -0.2

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  -55.7 -68.3   260   67   34   2.0   1.1      M     M       M      M    M
 45000  -52.5 -62.5   250   81   42   2.0   1.1      M     M       M      M    M
 40000  -49.4 -56.9   250   83   43   2.1   1.1      M     M       M      M    M
 38000  -48.2 -54.8   245   84   43   0.5   0.3      M     M       M      M    M
 36000  -48.3 -54.9   245   82   42  -0.1  -0.0      M     M       M      M    M
 34000  -48.3 -54.9   245   81   42  -0.1  -0.0      M     M       M      M    M
 32000  -46.7 -52.1   245   78   40   3.7   2.0      M     M       M      M    M
 30000  -44.5 -48.1   240   75   39   3.6   2.0      M     M       M      M    M
 29000  -43.5 -46.3   240   73   37   3.0   1.7   32.7  90.8    30.0      M    M
 28000  -42.6 -44.7   245   69   36   3.0   1.7   29.9  85.8    28.2      M    M
 27000  -41.7 -43.1   245   66   34   3.0   1.7   27.3  81.2    26.6      M    M
 26000  -40.8 -41.4   245   63   32   2.7   1.5   24.9  76.8    25.0      M    M
 25000  -40.1 -40.2   250   59   30   2.1   1.2   21.8  71.3    23.0      M    M
 24000  -39.5 -39.1   250   56   29   2.1   1.2   19.0  66.1    20.9      M    M
 23000  -38.9 -38.0   255   52   27   2.8   1.5   16.3  61.3    19.0      M    M
 22000  -37.6 -35.7   255   50   26   4.5   2.5   14.1  57.4    17.5      M    M
 21000  -36.2 -33.2   260   48   25   4.5   2.4   12.2  54.0    16.1      M    M
 20000  -34.7 -30.5   260   47   24   8.2   4.5   10.7  51.2    15.0      M    M
 19500  -33.5 -28.3   260   47   24   8.1   4.4   10.3  50.6    14.8      M    M
 19000  -32.3 -26.1   260   47   24   8.1   4.4   10.0  50.0    14.6      M    M
 18500  -31.1 -24.0   260   47   24   8.1   4.4    9.7  49.5    14.5      M    M
 18000  -29.8 -21.6   260   48   25   8.1   4.4    9.5  49.1    14.3      M    M
 17500  -28.6 -19.5   260   47   24   8.1   4.4    9.2  48.6    14.2      M    M
 17000  -27.4 -17.3   260   47   24   8.1   4.5    8.9  48.1    14.0      M    M
 16500  -25.8 -14.4   265   45   23   6.5   3.6    8.3  47.0    13.6      M    M
 16000  -24.8 -12.6   265   43   22   6.6   3.6    7.8  46.1    13.2      M    M
 15500  -23.8 -10.8   265   41   21   6.9   3.8    7.3  45.1    12.8      M    M
 15000  -22.7  -8.9   270   39   20   7.0   3.8    6.8  44.3    12.4      M    M
 14500  -21.8  -7.2   270   37   19   5.7   3.1    6.3  43.3    12.0      M    M
 14000  -21.0  -5.8   275   35   18   5.3   2.9    5.6  42.0    11.4      M    M
 13500  -20.2  -4.4   280   34   17   4.6   2.5    4.8  40.7    10.8      M    M
 13000  -19.6  -3.3   285   32   16   4.3   2.4    3.9  39.0    10.0      M    M
 12500  -19.0  -2.2   290   29   15   3.8   2.1    3.0  37.4     9.3      M    M
 12000  -18.4  -1.1   290   26   14   3.6   2.0    2.0  35.6     8.3      M    M
 11500  -18.0  -0.4   295   23   12   1.3   0.7    0.9  33.6     7.4      M    M
 11000  -17.9  -0.2   295   19   10   0.5   0.3   -0.6  30.9     6.0      M    M
 10500  -17.9  -0.2   300   15    8  -0.7  -0.4   -2.2  28.1     4.6      M    M
 10250  -18.0  -0.4   300   13    7  -0.7  -0.4   -3.0  26.6     3.8      M    M
 10000  -18.1  -0.6   300   11    6  -1.3  -0.7   -3.8  25.1     3.0      M    M
  9750  -18.1  -0.6   295    9    5   1.3   0.7   -4.7  23.6     2.2      M    M
  9500  -17.9  -0.2   295    8    4   4.4   2.4   -5.1  22.7     1.8      M    M
  9250  -17.6   0.3   295    6    3   3.9   2.1   -5.6  21.9     1.3      M    M
  9000  -17.3   0.9   290    4    2   4.2   2.3   -6.1  21.1     0.9      M    M
  8750  -16.9   1.6   285    2    1   5.9   3.2   -6.4  20.4     0.6      M    M
  8500  -16.4   2.5   325    1    0   7.3   4.0   -6.7  20.0     0.3      M    M
  8250  -15.9   3.4   075    2    1   7.2   3.9   -6.9  19.7     0.1      M    M
  8000  -15.3   4.5   080    3    2   7.9   4.3   -7.0  19.3    -0.1    171  0.9
  7750  -14.7   5.5   075    6    3   8.2   4.5   -7.2  19.1    -0.2    145  0.7
  7500  -14.1   6.6   065    8    4   7.4   4.1   -7.3  18.8    -0.3    121  0.6
  7250  -13.6   7.5   060    9    4   7.7   4.2   -7.5  18.5    -0.5     97  0.5
  7000  -13.0   8.6   055    9    5   8.3   4.6   -7.6  18.3    -0.7     72  0.4
  6750  -12.4   9.7   050    9    5   8.1   4.5   -7.7  18.1    -0.8     46  0.2
  6500  -11.8  10.8   045    9    5   8.2   4.5   -7.9  17.9    -0.9     21  0.1
  6250  -11.2  11.8   040    9    4   9.0   4.9   -7.9  17.7    -1.0      M    M
  6000  -10.5  13.1   035    8    4   9.3   5.1   -8.0  17.6    -1.1      M    M
  5750   -9.8  14.4   030    8    4   8.9   4.9   -8.0  17.6    -1.1      M    M
  5500   -9.1  15.6   025    7    4   9.3   5.1   -8.1  17.4    -1.2      M    M

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

           03/04/2015 at 0800 MST          |       03/04/2015 at 1100 MST
                                           |
K index... -3.2  LI... +279.9              | K index... -0.4  LI... +277.5
CAPE... 0.0  CIN... -0.3                   | 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 -55.9 -68.6  265  60 31   2.3   1.3 | -56.0 -68.8  260  54 28   2.8   1.5
 45000 -52.3 -62.1  260  70 36   2.3   1.3 | -51.9 -61.4  260  60 31   2.7   1.5
 40000 -48.7 -55.7  255  77 40   2.4   1.3 | -48.8 -55.8  255  64 33   2.0   1.1
 38000 -47.3 -53.1  250  80 41   0.8   0.4 | -47.6 -53.7  255  65 33   1.8   1.0
 36000 -47.2 -53.0  250  80 41   0.2   0.1 | -46.5 -51.7  255  67 34   1.7   0.9
 34000 -47.0 -52.6  245  80 41   0.2   0.1 | -45.5 -49.9  255  69 35   1.7   0.9
 32000 -46.0 -50.8  245  80 41   2.2   1.2 | -44.7 -48.5  250  70 36   1.0   0.5
 30000 -44.7 -48.5  245  79 41   2.2   1.2 | -44.1 -47.4  250  70 36   1.0   0.5
 29000 -44.1 -47.4  245  76 39   1.6   0.9 | -43.7 -46.7  250  68 35   1.4   0.8
 28000 -43.6 -46.5  245  70 36   1.7   0.9 | -43.3 -45.9  250  62 32   1.4   0.8
 27000 -43.1 -45.6  245  64 33   1.7   0.9 | -42.9 -45.2  250  55 29   1.4   0.8
 26000 -42.6 -44.7  250  58 30   2.0   1.1 | -42.4 -44.3  255  49 25   1.7   0.9
 25000 -41.8 -43.2  250  53 27   2.7   1.5 | -41.7 -43.1  260  46 24   2.5   1.4
 24000 -41.0 -41.8  255  49 25   2.8   1.5 | -41.0 -41.8  265  44 22   2.5   1.4
 23000 -40.2 -40.4  265  46 24   3.5   1.9 | -40.2 -40.4  270  42 21   2.8   1.6
 22000 -38.7 -37.7  265  45 23   5.2   2.9 | -39.1 -38.4  275  41 21   4.0   2.2
 21000 -37.1 -34.8  270  45 23   5.2   2.9 | -37.9 -36.2  275  42 21   4.0   2.2
 20000 -35.4 -31.7  270  44 23   7.2   4.0 | -36.5 -33.7  280  41 21   6.3   3.5
 19500 -34.4 -29.9  270  43 22   7.1   3.9 | -35.6 -32.1  280  41 21   6.3   3.5
 19000 -33.3 -27.9  270  43 22   7.1   3.9 | -34.7 -30.5  280  40 21   6.3   3.5
 18500 -32.2 -26.0  270  42 22   7.2   3.9 | -33.7 -28.7  280  39 20   6.3   3.5
 18000 -31.2 -24.2  270  42 21   7.3   4.0 | -32.8 -27.0  280  38 20   6.2   3.4
 17500 -30.1 -22.2  270  41 21   6.4   3.5 | -31.8 -25.2  280  38 19   7.2   4.0
 17000 -29.2 -20.6  275  40 21   6.5   3.6 | -30.2 -22.4  280  37 19   6.9   3.8
 16500 -27.7 -17.9  275  39 20   6.5   3.5 | -29.3 -20.7  285  36 19   5.5   3.0
 16000 -26.8 -16.2  280  39 20   6.6   3.6 | -28.5 -19.3  290  35 18   5.5   3.0
 15500 -25.9 -14.6  285  38 20   5.2   2.8 | -27.6 -17.7  295  35 18   6.0   3.3
 15000 -25.1 -13.2  285  38 20   5.2   2.9 | -26.7 -16.1  300  36 18   5.7   3.2
 14500 -24.3 -11.7  290  38 20   6.2   3.4 | -25.7 -14.3  300  36 18   8.5   4.6
 14000 -23.3  -9.9  295  38 19   6.3   3.4 | -24.4 -11.9  300  35 18   8.6   4.7
 13500 -22.4  -8.3  295  37 19   6.3   3.5 | -23.2  -9.8  300  34 18   8.4   4.6
 13000 -21.4  -6.5  295  35 18   6.4   3.5 | -21.9  -7.4  300  32 16   8.4   4.6
 12500 -20.5  -4.9  295  32 17   5.3   2.9 | -20.7  -5.3  300  30 15   7.4   4.1
 12000 -19.8  -3.6  295  29 15   5.2   2.9 | -19.6  -3.3  300  29 15   7.3   4.0
 11500 -19.1  -2.4  295  26 13   3.5   1.9 | -18.6  -1.5  300  27 14   6.8   3.7
 11000 -18.6  -1.5  295  23 12   3.7   2.0 | -17.6   0.3  295  24 12   7.2   3.9
 10500 -18.4  -1.1  290  19 10  -0.8  -0.4 | -16.8   1.8  295  21 11   3.0   1.7
 10250 -18.5  -1.3  290  17  9  -0.5  -0.3 | -16.6   2.1  295  19 10   3.4   1.9
 10000 -18.5  -1.3  285  15  8  -0.8  -0.4 | -16.3   2.7  295  18  9   3.6   2.0
  9750 -18.5  -1.3  285  13  7   2.1   1.1 | -16.1   3.0  295  17  9   0.9   0.5
  9500 -18.2  -0.8  280  12  6   4.8   2.6 | -16.2   2.8  290  14  7  -1.8  -1.0
  9250 -17.9  -0.2  275  10  5   4.5   2.5 | -16.3   2.7  285  12  6  -2.3  -1.3
  9000 -17.6   0.3  270   8  4   4.6   2.5 | -16.5   2.3  275   9  5   0.5   0.3
  8750 -17.2   1.0  260   6  3   5.4   2.9 | -16.2   2.8  265   7  4   5.1   2.8
  8500 -16.7   1.9  245   4  2   6.4   3.5 | -15.8   3.6  250   6  3   6.1   3.3
  8250 -16.3   2.7  200   2  1   6.7   3.7 | -15.3   4.5  225   5  3   6.3   3.4
  8000 -15.8   3.6  150   3  1   6.4   3.5 | -14.9   5.2  200   5  2   5.7   3.1
  7750 -15.3   4.5  120   4  2   6.5   3.6 | -14.5   5.9  175   5  2   6.0   3.3
  7500 -14.8   5.4  105   5  3   6.8   3.7 | -14.0   6.8  150   5  3   6.8   3.7
  7250 -14.3   6.3  095   6  3   7.3   4.0 | -13.5   7.7  135   6  3   7.3   4.0
  7000 -13.7   7.3  090   6  3   8.0   4.4 | -12.9   8.8  120   6  3   7.6   4.2
  6750 -13.2   8.2  080   6  3   6.9   3.8 | -12.4   9.7  105   6  3   7.5   4.1
  6500 -12.7   9.1  075   6  3   7.8   4.3 | -11.8  10.8  095   6  3   9.3   5.1
  6250 -12.0  10.4  065   6  3   9.8   5.4 | -11.0  12.2  095   6  3  10.8   5.9
  6000 -11.3  11.7  060   6  3   9.6   5.3 | -10.2  13.6  090   6  3  10.5   5.7
  5750 -10.5  13.1  050   5  3  10.1   5.5 |  -9.4  15.1  090   6  3  11.3   6.2
  5500  -9.7  14.5  050   5  3  12.0   6.6 |  -8.5  16.7  085   6  3  14.4   7.9

           03/04/2015 at 1400 MST          |       03/04/2015 at 1700 MST
                                           |
K index... +2.8  LI... +275.7              | K index... +0.7  LI... +277.2
CAPE... 0.0  CIN... M                      | 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 -55.8 -68.4  260  52 27   2.5   1.4 | -56.4 -69.5  260  49 25   2.4   1.3
 45000 -52.0 -61.6  260  57 29   2.5   1.4 | -52.7 -62.9  265  52 27   2.4   1.3
 40000 -48.5 -55.3  260  58 30   2.3   1.3 | -48.9 -56.0  260  49 25   2.5   1.4
 38000 -47.2 -53.0  255  59 30   1.9   1.1 | -47.5 -53.5  260  48 25   0.7   0.4
 36000 -46.1 -51.0  260  58 30   1.9   1.0 | -47.2 -53.0  270  45 23   0.5   0.3
 34000 -44.8 -48.6  265  58 30   1.8   1.0 | -46.8 -52.2  280  44 23   0.6   0.3
 32000 -44.2 -47.6  265  56 29   0.5   0.3 | -46.2 -51.2  300  39 20   1.2   0.7
 30000 -43.9 -47.0  260  53 27   0.5   0.3 | -45.5 -49.9  325  40 21   1.3   0.7
 29000 -43.6 -46.5  265  51 26   1.9   1.1 | -44.8 -48.6  340  43 22   3.6   2.0
 28000 -43.1 -45.6  265  47 24   1.9   1.0 | -43.7 -46.7  345  47 24   3.7   2.0
 27000 -42.5 -44.5  270  44 23   1.9   1.0 | -42.6 -44.7  350  52 27   3.7   2.0
 26000 -41.9 -43.4  275  41 21   1.9   1.1 | -41.5 -42.7  355  57 29   4.2   2.3
 25000 -41.3 -42.3  280  39 20   2.1   1.2 | -40.1 -40.2  355  57 29   4.6   2.5
 24000 -40.7 -41.3  285  38 20   2.1   1.2 | -38.7 -37.7  355  58 30   4.6   2.5
 23000 -40.0 -40.0  295  38 19   2.5   1.4 | -37.4 -35.3  355  58 30   4.1   2.2
 22000 -39.0 -38.2  295  38 20   3.6   2.0 | -36.3 -33.3  355  54 28   3.6   1.9
 21000 -37.9 -36.2  300  39 20   3.6   2.0 | -35.2 -31.4  350  49 25   3.6   1.9
 20000 -36.7 -34.1  300  40 20   5.4   3.0 | -34.1 -29.4  345  46 24   3.7   2.0
 19500 -35.9 -32.6  300  40 21   5.4   2.9 | -33.6 -28.5  345  44 23   3.7   2.0
 19000 -35.1 -31.2  300  40 21   5.4   2.9 | -33.0 -27.4  340  43 22   3.7   2.0
 18500 -34.3 -29.7  295  41 21   5.4   2.9 | -32.5 -26.5  340  41 21   3.7   2.0
 18000 -33.1 -27.6  295  41 21   6.3   3.5 | -31.6 -24.9  335  39 20   4.2   2.3
 17500 -32.0 -25.6  295  41 21   7.1   3.9 | -31.0 -23.8  330  38 20   4.5   2.5
 17000 -31.0 -23.8  295  41 21   7.2   4.0 | -30.3 -22.5  325  37 19   4.7   2.6
 16500 -29.9 -21.8  295  41 21   7.5   4.1 | -29.5 -21.1  320  36 18   5.2   2.9
 16000 -28.8 -19.8  290  41 21   7.5   4.1 | -28.8 -19.8  315  35 18   5.2   2.9
 15500 -27.6 -17.7  290  40 21   7.9   4.3 | -27.8 -18.0  310  34 18   7.9   4.4
 15000 -26.4 -15.5  290  40 21   7.7   4.3 | -26.6 -15.9  310  33 17   7.6   4.2
 14500 -25.2 -13.4  290  40 20   9.0   5.0 | -25.4 -13.7  305  33 17   8.6   4.7
 14000 -23.8 -10.8  290  39 20   9.1   5.0 | -24.2 -11.6  305  32 17   8.5   4.7
 13500 -22.5  -8.5  290  38 19   8.8   4.8 | -22.9  -9.2  300  32 17   8.5   4.7
 13000 -21.2  -6.2  290  36 18   8.9   4.9 | -21.6  -6.9  300  32 16   8.5   4.7
 12500 -19.9  -3.8  290  34 17   7.9   4.4 | -20.4  -4.7  300  31 16   8.5   4.7
 12000 -18.8  -1.8  290  30 16   8.2   4.5 | -19.1  -2.4  300  30 15   8.7   4.8
 11500 -17.8  -0.0  290  27 14   4.5   2.5 | -17.9  -0.2  300  28 14   6.6   3.6
 11000 -17.1   1.2  290  22 12   5.0   2.7 | -16.9   1.6  300  25 13   6.8   3.7
 10500 -16.8   1.8  290  18  9  -0.2  -0.1 | -16.2   2.8  300  22 11   3.2   1.8
 10250 -16.8   1.8  285  15  8   0.7   0.4 | -16.0   3.2  295  19 10   4.2   2.3
 10000 -16.8   1.8  285  13  7  -0.3  -0.2 | -15.7   3.7  295  17  9   1.7   1.0
  9750 -16.7   1.9  280  12  6   2.3   1.3 | -15.6   3.9  295  17  9   2.0   1.1
  9500 -16.4   2.5  275  10  5   5.5   3.0 | -15.3   4.5  290  15  8   5.1   2.8
  9250 -16.0   3.2  265   8  4   5.3   2.9 | -15.0   5.0  285  13  7   5.2   2.8
  9000 -15.6   3.9  250   7  3   5.0   2.8 | -14.6   5.7  275  11  6   4.1   2.2
  8750 -15.3   4.5  240   6  3   5.4   3.0 | -14.3   6.3  270  10  5   4.0   2.2
  8500 -14.8   5.4  230   5  3   6.7   3.7 | -14.0   6.8  260   8  4   5.8   3.2
  8250 -14.3   6.3  210   5  2   6.5   3.6 | -13.5   7.7  250   7  4   5.6   3.1
  8000 -13.9   7.0  190   4  2   5.2   2.9 | -13.1   8.4  235   6  3   5.2   2.8
  7750 -13.5   7.7  155   4  2   5.2   2.8 | -12.8   9.0  225   4  2   4.9   2.7
  7500 -13.1   8.4  125   5  3   5.8   3.2 | -12.4   9.7  205   3  2   5.0   2.7
  7250 -12.6   9.3  110   6  3   8.3   4.6 | -12.0  10.4  170   2  1   7.3   4.0
  7000 -11.9  10.6  100   6  3  10.6   5.8 | -11.4  11.5  130   1  1   8.8   4.9
  6750 -11.1  12.0  090   6  3   9.0   5.0 | -10.7  12.7  090   2  1   8.3   4.6
  6500 -10.5  13.1  085   7  3   9.5   5.2 | -10.1  13.8  070   2  1   9.3   5.1
  6250  -9.7  14.5  085   6  3  11.0   6.1 |  -9.4  15.1  065   2  1  10.1   5.5
  6000  -8.9  16.0  085   6  3  10.5   5.8 |  -8.6  16.5  060   3  1   9.9   5.4
  5750  -8.1  17.4  080   6  3  11.7   6.4 |  -7.9  17.8  055   3  1  10.0   5.5
  5500  -7.1  19.2  080   6  3  15.2   8.3 |  -7.2  19.0  055   3  1  10.6   5.8
________________________________________________________________________________

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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