Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 040021
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1721 MST Tuesday, March 3, 2015

This forecast is for Wednesday, March 4, 2015:

If the trigger temperature of 23.8 F/-4.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 78 ft/min (0.4 m/s)
   Maximum height of thermals.................. 6968 ft MSL (1661 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)......... Little change
Height of stable layer (12-18K ft MSL)......... 12200 ft MSL (6893 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 19340 ft MSL (14033 ft AGL)
Wave soaring outlook for Thursday 03/05........ Good

Remarks... Arctic air lingering over northeast colorado Wednesday as upper
           trough begins to move out of area.

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... 8445 ft MSL (3138 ft AGL)
Lifted condensation level....... 7943 ft MSL (2636 ft AGL)
Lifted index.................... +16.1
K index......................... +1.8

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  -54.9 -66.8   260   67   34   1.7   0.9      M     M       M      M    M
 45000  -52.3 -62.1   250   78   40   1.7   0.9      M     M       M      M    M
 40000  -49.4 -56.9   250   81   42   1.9   1.1      M     M       M      M    M
 38000  -48.3 -54.9   245   82   42   0.9   0.5      M     M       M      M    M
 36000  -48.0 -54.4   245   78   40   0.5   0.3      M     M       M      M    M
 34000  -47.7 -53.9   245   75   38   0.5   0.3      M     M       M      M    M
 32000  -46.3 -51.3   245   71   37   3.1   1.7      M     M       M      M    M
 30000  -44.4 -47.9   245   69   35   3.1   1.7      M     M       M      M    M
 29000  -43.5 -46.3   245   67   35   2.5   1.4   32.6  90.7    29.9      M    M
 28000  -42.8 -45.0   245   65   33   2.5   1.4   29.6  85.3    28.0      M    M
 27000  -42.0 -43.6   245   63   32   2.5   1.4   26.8  80.2    26.2      M    M
 26000  -41.3 -42.3   245   61   31   2.4   1.3   24.2  75.5    24.5      M    M
 25000  -40.6 -41.1   245   56   29   2.2   1.2   21.2  70.1    22.4      M    M
 24000  -39.9 -39.8   245   52   27   2.2   1.2   18.3  65.0    20.4      M    M
 23000  -39.3 -38.7   250   48   25   2.9   1.6   15.7  60.2    18.5      M    M
 22000  -38.0 -36.4   250   47   24   4.6   2.5   13.6  56.4    17.0      M    M
 21000  -36.6 -33.9   250   46   24   4.5   2.5   11.7  53.0    15.7      M    M
 20000  -34.9 -30.8   250   45   23   9.7   5.3   10.3  50.5    14.7      M    M
 19500  -33.5 -28.3   250   45   23   9.5   5.2   10.2  50.3    14.7      M    M
 19000  -32.1 -25.8   250   44   23   9.5   5.2   10.1  50.2    14.7      M    M
 18500  -30.7 -23.3   255   44   23   9.5   5.2   10.1  50.1    14.7      M    M
 18000  -29.3 -20.7   255   44   22   9.8   5.4   10.1  50.1    14.8      M    M
 17500  -28.0 -18.4   255   43   22   7.0   3.9    9.9  49.7    14.7      M    M
 17000  -26.4 -15.5   260   41   21   7.3   4.0    9.2  48.6    14.3      M    M
 16500  -25.3 -13.5   260   40   20   7.3   4.0    8.8  47.8    14.0      M    M
 16000  -24.3 -11.7   265   38   19   7.3   4.0    8.4  47.1    13.7      M    M
 15500  -23.2  -9.8   265   36   18   6.9   3.8    7.9  46.3    13.3      M    M
 15000  -22.2  -8.0   265   33   17   6.9   3.8    7.4  45.4    13.0      M    M
 14500  -21.2  -6.2   270   31   16   6.2   3.4    6.9  44.5    12.6      M    M
 14000  -20.3  -4.5   275   30   15   6.1   3.3    6.3  43.4    12.1      M    M
 13500  -19.4  -2.9   280   28   15   4.1   2.3    5.7  42.2    11.5      M    M
 13000  -19.0  -2.2   280   26   13   3.1   1.7    4.5  40.2    10.6      M    M
 12500  -18.6  -1.5   285   23   12   0.8   0.4    3.4  38.1     9.6      M    M
 12000  -18.7  -1.7   280   19   10  -0.6  -0.3    1.7  35.1     8.1      M    M
 11500  -18.8  -1.8   280   14    7   0.2   0.1    0.1  32.1     6.6      M    M
 11000  -18.7  -1.7   275   11    6   0.3   0.2   -1.4  29.4     5.2      M    M
 10500  -18.4  -1.1   270    7    4   4.8   2.7   -2.7  27.2     4.1      M    M
 10250  -18.0  -0.4   265    6    3   6.0   3.3   -3.0  26.6     3.8      M    M
 10000  -17.5   0.5   265    4    2   5.5   3.0   -3.3  26.1     3.5      M    M
  9750  -17.1   1.2   255    2    1   6.3   3.4   -3.6  25.5     3.2      M    M
  9500  -16.7   1.9   075    1    0   4.5   2.5   -3.9  25.0     2.9      M    M
  9250  -16.4   2.5   075    3    1   2.4   1.3   -4.5  24.0     2.4      M    M
  9000  -16.2   2.8   075    5    2   3.3   1.8   -5.0  23.0     1.9      M    M
  8750  -15.9   3.4   075    7    3   5.6   3.1   -5.4  22.3     1.5      M    M
  8500  -15.4   4.3   070    8    4   7.2   3.9   -5.7  21.8     1.3      M    M
  8250  -14.9   5.2   065   10    5   6.4   3.5   -5.9  21.4     1.1      M    M
  8000  -14.4   6.1   060   12    6   8.3   4.5   -6.1  21.0     0.8      M    M
  7750  -13.7   7.3   060   13    7   9.0   5.0   -6.1  20.9     0.8      M    M
  7500  -13.1   8.4   055   14    7   7.6   4.2   -6.3  20.7     0.7      M    M
  7250  -12.6   9.3   050   14    7   6.3   3.5   -6.5  20.4     0.5      M    M
  7000  -12.2  10.0   045   14    7   4.2   2.3   -6.8  19.7     0.1      M    M
  6750  -11.9  10.6   035   14    7   4.0   2.2   -7.3  18.9    -0.3     66  0.3
  6500  -11.6  11.1   025   14    7   5.1   2.8   -7.7  18.2    -0.7     49  0.2
  6250  -11.1  12.0   020   13    7   7.4   4.0   -7.9  17.7    -1.0     28  0.1
  6000  -10.5  13.1   010   12    6   8.3   4.6   -8.1  17.5    -1.1      3  0.0
  5750   -9.9  14.2   005   11    6   8.5   4.6   -8.2  17.3    -1.3      M    M
  5500   -9.2  15.4   360   11    5  11.1   6.1   -8.2  17.3    -1.3      M    M

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

           03/04/2015 at 0800 MST          |       03/04/2015 at 1100 MST
                                           |
K index... -1.8  LI... +281.3              | K index... -3.9  LI... +280.4
CAPE... 0.0  CIN... -0.7                   | CAPE... +20.0  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 -55.1 -67.2  260  63 32   1.8   1.0 | -55.6 -68.1  260  58 30   2.4   1.3
 45000 -52.2 -62.0  255  71 36   1.8   1.0 | -51.9 -61.4  255  64 33   2.4   1.3
 40000 -49.6 -57.3  250  72 37   1.8   1.0 | -49.1 -56.4  255  64 33   1.7   1.0
 38000 -48.6 -55.5  250  72 37   1.3   0.7 | -48.1 -54.6  255  63 33   1.7   0.9
 36000 -47.8 -54.0  250  73 37   1.2   0.7 | -47.1 -52.8  250  65 33   1.6   0.9
 34000 -47.1 -52.8  245  73 38   1.2   0.7 | -46.1 -51.0  250  66 34   1.6   0.9
 32000 -45.7 -50.3  245  72 37   2.5   1.4 | -44.9 -48.8  250  66 34   1.9   1.0
 30000 -44.2 -47.6  245  70 36   2.5   1.4 | -43.8 -46.8  245  65 34   1.9   1.0
 29000 -43.6 -46.5  245  68 35   1.7   0.9 | -43.2 -45.8  245  64 33   1.5   0.8
 28000 -43.0 -45.4  245  65 33   1.7   0.9 | -42.8 -45.0  245  60 31   1.6   0.9
 27000 -42.5 -44.5  245  62 32   1.7   0.9 | -42.3 -44.1  245  56 29   1.6   0.9
 26000 -42.0 -43.6  245  58 30   2.1   1.1 | -41.8 -43.2  245  52 27   1.7   0.9
 25000 -41.2 -42.2  245  55 28   2.9   1.6 | -41.2 -42.2  250  50 26   2.2   1.2
 24000 -40.3 -40.5  250  52 27   2.9   1.6 | -40.5 -40.9  250  47 24   2.2   1.2
 23000 -39.4 -38.9  250  49 25   3.3   1.8 | -39.9 -39.8  255  45 23   2.6   1.4
 22000 -38.1 -36.6  255  48 24   4.6   2.5 | -38.7 -37.7  255  43 22   4.3   2.3
 21000 -36.8 -34.2  255  46 24   4.6   2.5 | -37.4 -35.3  260  41 21   4.3   2.3
 20000 -35.3 -31.5  255  45 23   6.4   3.5 | -36.0 -32.8  265  39 20   5.4   3.0
 19500 -34.3 -29.7  255  44 23   6.4   3.5 | -35.2 -31.4  265  40 20   5.5   3.0
 19000 -33.4 -28.1  255  44 23   6.4   3.5 | -34.4 -29.9  260  40 20   5.6   3.0
 18500 -32.4 -26.3  260  43 22   6.4   3.5 | -33.6 -28.5  260  40 20   5.6   3.1
 18000 -31.4 -24.5  260  43 22   6.3   3.5 | -32.7 -26.9  260  40 20   5.6   3.1
 17500 -30.4 -22.7  260  42 22   7.5   4.1 | -31.9 -25.4  260  39 20   5.4   3.0
 17000 -29.3 -20.7  260  40 21   7.4   4.1 | -31.1 -24.0  265  37 19   5.4   3.0
 16500 -27.6 -17.7  265  38 19   8.3   4.6 | -29.8 -21.6  270  36 19   6.3   3.5
 16000 -26.4 -15.5  265  36 18   8.5   4.7 | -28.9 -20.0  275  38 20   6.0   3.3
 15500 -25.3 -13.5  270  34 18   6.0   3.3 | -27.8 -18.0  275  39 20   9.0   5.0
 15000 -24.4 -11.9  270  32 17   6.1   3.3 | -26.5 -15.7  275  39 20   9.1   5.0
 14500 -23.5 -10.3  275  31 16   5.4   2.9 | -25.2 -13.4  280  38 20   6.4   3.5
 14000 -22.7  -8.9  280  30 16   5.3   2.9 | -24.3 -11.7  285  37 19   6.1   3.3
 13500 -22.0  -7.6  285  29 15   3.5   1.9 | -23.5 -10.3  285  35 18   4.2   2.3
 13000 -21.6  -6.9  290  27 14   2.9   1.6 | -23.0  -9.4  285  31 16   3.8   2.1
 12500 -21.2  -6.2  290  24 12   1.8   1.0 | -22.5  -8.5  285  27 14   2.0   1.1
 12000 -21.0  -5.8  290  20 10   1.4   0.8 | -22.3  -8.1  285  21 11   1.4   0.8
 11500 -20.8  -5.4  285  16  8   1.4   0.8 | -22.0  -7.6  280  15  8   3.8   2.1
 11000 -20.6  -5.1  280  11  6   1.1   0.6 | -21.4  -6.5  270   9  5   3.8   2.1
 10500 -20.2  -4.4  275   6  3   5.0   2.7 | -20.5  -4.9  250   4  2   7.4   4.0
 10250 -19.8  -3.6  275   4  2   5.5   3.0 | -20.0  -4.0  230   3  1   7.7   4.2
 10000 -19.4  -2.9  280   2  1   4.2   2.3 | -19.5  -3.1  185   2  1   5.7   3.1
  9750 -19.1  -2.4  000   0  0   4.5   2.5 | -19.1  -2.4  155   2  1   5.1   2.8
  9500 -18.7  -1.7  075   1  1   7.7   4.2 | -18.6  -1.5  120   3  1   8.2   4.5
  9250 -18.0  -0.4  080   3  2   9.2   5.0 | -18.0  -0.4  100   4  2   9.4   5.2
  9000 -17.4   0.7  080   5  3   7.5   4.1 | -17.3   0.9  085   5  3   7.5   4.1
  8750 -16.9   1.6  080   7  4   6.4   3.5 | -16.8   1.8  080   6  3   6.3   3.5
  8500 -16.4   2.5  075   9  4   7.5   4.1 | -16.3   2.7  075   7  4   7.6   4.2
  8250 -15.8   3.6  075  10  5   7.8   4.3 | -15.7   3.7  070   8  4   7.8   4.3
  8000 -15.2   4.6  070  11  6   7.4   4.1 | -15.2   4.6  070   8  4   7.6   4.2
  7750 -14.7   5.5  065  11  6   7.3   4.0 | -14.6   5.7  065   9  5   7.5   4.1
  7500 -14.1   6.6  060  12  6   7.7   4.2 | -14.1   6.6  060   9  5   7.3   4.0
  7250 -13.6   7.5  055  12  6   7.2   3.9 | -13.5   7.7  055  10  5   8.5   4.7
  7000 -13.1   8.4  050  12  6   6.9   3.8 | -12.8   9.0  055   9  5   9.5   5.2
  6750 -12.6   9.3  040  11  6   6.1   3.3 | -12.1  10.2  050   9  5   9.4   5.2
  6500 -12.2  10.0  035  11  6   6.3   3.5 | -11.4  11.5  045   9  5  10.2   5.6
  6250 -11.6  11.1  025  10  5   8.2   4.5 | -10.6  12.9  045   9  5  10.7   5.9
  6000 -11.0  12.2  020   9  5   8.2   4.5 |  -9.8  14.4  045   9  4  10.2   5.6
  5750 -10.4  13.3  010   8  4   8.8   4.8 |  -9.1  15.6  040   8  4  11.8   6.5
  5500  -9.6  14.7  010   8  4  11.5   6.3 |  -8.0  17.6  040   8  4  16.4   9.0

           03/04/2015 at 1400 MST          |       03/04/2015 at 1700 MST
                                           |
K index... -3.7  LI... +278.9              | K index... -3.1  LI... +278.4
CAPE... +4.6  CIN... -1.1                  | 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 -55.5 -67.9  265  51 26   2.4   1.3 | -55.8 -68.4  265  48 25   2.7   1.5
 45000 -51.7 -61.1  260  57 29   2.4   1.3 | -51.5 -60.7  265  53 27   2.7   1.5
 40000 -48.8 -55.8  255  58 30   1.8   1.0 | -48.7 -55.7  260  52 27   1.8   1.0
 38000 -47.8 -54.0  255  58 30   1.5   0.8 | -47.7 -53.9  260  51 26   0.5   0.3
 36000 -46.9 -52.4  255  56 29   1.4   0.8 | -47.7 -53.9  270  46 24  -0.0  -0.0
 34000 -46.1 -51.0  260  53 27   1.4   0.8 | -47.7 -53.9  280  43 22  -0.0  -0.0
 32000 -45.1 -49.2  260  51 26   1.5   0.8 | -47.1 -52.8  300  38 20   1.4   0.8
 30000 -44.1 -47.4  260  48 25   1.5   0.8 | -46.2 -51.2  320  37 19   1.5   0.8
 29000 -43.7 -46.7  260  47 24   1.7   0.9 | -45.5 -49.9  330  39 20   3.5   1.9
 28000 -43.2 -45.8  260  45 23   1.7   0.9 | -44.5 -48.1  335  41 21   3.4   1.9
 27000 -42.7 -44.9  265  43 22   1.7   0.9 | -43.5 -46.3  340  44 23   3.4   1.9
 26000 -42.2 -44.0  265  41 21   1.8   1.0 | -42.4 -44.3  345  48 24   3.5   1.9
 25000 -41.4 -42.5  270  39 20   2.6   1.4 | -41.3 -42.3  345  48 25   3.7   2.0
 24000 -40.7 -41.3  270  39 20   2.6   1.4 | -40.2 -40.4  345  48 24   3.7   2.0
 23000 -39.9 -39.8  275  38 20   2.7   1.5 | -39.1 -38.4  345  47 24   3.7   2.0
 22000 -38.9 -38.0  280  38 19   3.4   1.9 | -38.0 -36.4  340  45 23   3.8   2.1
 21000 -37.9 -36.2  280  38 19   3.4   1.9 | -36.8 -34.2  335  43 22   3.8   2.1
 20000 -36.7 -34.1  285  38 19   5.0   2.7 | -35.6 -32.1  335  41 21   4.3   2.4
 19500 -36.0 -32.8  285  37 19   5.1   2.8 | -35.0 -31.0  330  40 20   4.3   2.4
 19000 -35.2 -31.4  285  37 19   5.1   2.8 | -34.4 -29.9  325  39 20   4.3   2.4
 18500 -34.4 -29.9  285  37 19   5.1   2.8 | -33.7 -28.7  325  39 20   4.3   2.4
 18000 -33.7 -28.7  285  37 19   5.1   2.8 | -33.1 -27.6  320  38 20   4.3   2.4
 17500 -32.8 -27.0  285  37 19   6.0   3.3 | -32.4 -26.3  315  37 19   4.7   2.6
 17000 -32.0 -25.6  285  37 19   6.0   3.3 | -31.7 -25.1  310  37 19   4.6   2.5
 16500 -30.5 -22.9  285  38 20   7.6   4.2 | -30.6 -23.1  305  36 19   5.6   3.1
 16000 -29.4 -20.9  285  39 20   7.5   4.1 | -29.7 -21.5  300  35 18   5.5   3.0
 15500 -28.3 -18.9  285  40 20   7.5   4.1 | -28.7 -19.7  300  35 18   8.5   4.7
 15000 -27.1 -16.8  285  40 20   7.5   4.1 | -27.4 -17.3  295  34 18   8.2   4.5
 14500 -26.0 -14.8  285  40 20   7.6   4.2 | -26.2 -15.2  295  34 18   8.4   4.6
 14000 -24.9 -12.8  290  39 20   7.8   4.3 | -25.0 -13.0  290  35 18   8.4   4.6
 13500 -23.8 -10.8  290  38 19   6.1   3.4 | -23.7 -10.7  290  35 18   8.8   4.8
 13000 -23.0  -9.4  290  34 17   6.0   3.3 | -22.4  -8.3  290  34 17   9.1   5.0
 12500 -22.2  -8.0  285  29 15   3.0   1.6 | -21.2  -6.2  290  32 16   6.2   3.4
 12000 -21.9  -7.4  285  23 12   2.3   1.3 | -20.3  -4.5  290  29 15   6.6   3.6
 11500 -21.4  -6.5  280  17  9   4.4   2.4 | -19.7  -3.5  290  25 13   1.4   0.7
 11000 -20.8  -5.4  270  11  6   4.2   2.3 | -19.5  -3.1  285  20 10   1.6   0.9
 10500 -19.9  -3.8  255   6  3   7.8   4.3 | -19.0  -2.2  280  16  8   5.0   2.8
 10250 -19.3  -2.7  255   4  2   8.1   4.5 | -18.6  -1.5  275  13  7   5.2   2.8
 10000 -18.7  -1.7  250   2  1   5.4   3.0 | -18.2  -0.8  265  12  6   3.2   1.7
  9750 -18.5  -1.3  240   1  0   4.1   2.2 | -18.1  -0.6  260  11  5   3.4   1.9
  9500 -18.0  -0.4  005   1  1   7.3   4.0 | -17.7   0.1  265   8  4   6.7   3.7
  9250 -17.4   0.7  020   3  1   8.2   4.5 | -17.1   1.2  265   6  3   7.4   4.0
  9000 -16.8   1.8  025   5  2   6.8   3.7 | -16.6   2.1  270   3  2   5.0   2.8
  8750 -16.4   2.5  025   5  3   6.2   3.4 | -16.3   2.7  285   3  1   4.7   2.6
  8500 -15.9   3.4  030   6  3   7.7   4.2 | -15.9   3.4  310   2  1   8.0   4.4
  8250 -15.3   4.5  035   6  3   7.8   4.3 | -15.2   4.6  345   2  1   8.0   4.4
  8000 -14.7   5.5  040   6  3   7.4   4.1 | -14.7   5.5  010   2  1   7.1   3.9
  7750 -14.2   6.4  050   7  4   7.5   4.1 | -14.2   6.4  025   3  2   7.5   4.1
  7500 -13.6   7.5  050   8  4   7.8   4.3 | -13.6   7.5  035   4  2   8.3   4.6
  7250 -13.0   8.6  050   8  4   8.8   4.8 | -13.0   8.6  040   4  2   8.7   4.8
  7000 -12.3   9.9  050   8  4   9.9   5.4 | -12.3   9.9  040   4  2   8.6   4.7
  6750 -11.6  11.1  045   8  4   8.6   4.7 | -11.7  10.9  040   5  2   9.1   5.0
  6500 -11.0  12.2  045   8  4   9.5   5.2 | -11.0  12.2  040   5  3   9.5   5.2
  6250 -10.2  13.6  045   8  4  11.6   6.4 | -10.3  13.5  040   5  3   9.5   5.2
  6000  -9.4  15.1  045   8  4  11.1   6.1 |  -9.6  14.7  035   5  3   9.1   5.0
  5750  -8.5  16.7  045   8  4  12.0   6.6 |  -8.9  16.0  035   5  3  10.6   5.8
  5500  -7.5  18.5  045   8  4  15.1   8.3 |  -8.0  17.6  030   5  2  13.9   7.6
________________________________________________________________________________

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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