Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 220051
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1851 MDT Thursday, March 21, 2024

This forecast is for Friday, March 22, 2024:

If the trigger temperature of 51.1 F/10.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 803 ft/min (4.1 m/s)
   Maximum height of thermals.................. 15379 ft MSL (10079 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... 1100 MDT
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................. 12176 ft MSL (6875 ft AGL)
Thermal soaring outlook for Saturday 03/23..... Excellent

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... Becoming fair as flow aloft weak
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 15392 ft MSL (10092 ft AGL)
Wave soaring outlook for Saturday 03/23........ Fair

Remarks...

Sunrise/Sunset.................... 06:58:15 / 19:13:55 MDT
Total possible sunshine........... 12 hr 15 min 41 sec (735 min 41 sec)
Altitude of sun at 13:06:05 MDT... 51.26 degrees

Upper air data from numerical model forecast valid on 03/22/2024 at 0600 MDT

Freezing level.................. 5334 ft MSL (34 ft AGL)
Additional freezing level....... 8406 ft MSL (3106 ft AGL)
Convective condensation level... 14076 ft MSL (8776 ft AGL)
Lifted condensation level....... 14759 ft MSL (9459 ft AGL)
Lifted index.................... -1.2
K index......................... -15.1

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  -57.7 -71.9   280   44   23   2.9   1.6      M     M       M      M    M
 45000  -53.1 -63.6   285   51   26   3.5   1.9      M     M       M      M    M
 40000  -57.7 -71.9   290   52   27  -3.5  -1.9      M     M       M      M    M
 38000  -59.2 -74.6   295   52   27   0.0   0.0      M     M       M      M    M
 36000  -59.1 -74.4   295   51   26   0.1   0.1      M     M       M      M    M
 34000  -59.1 -74.4   295   50   26   2.9   1.6      M     M       M      M    M
 32000  -53.8 -64.8   300   47   24   8.0   4.4      M     M       M      M    M
 30000  -49.0 -56.2   305   44   23   8.5   4.7   26.2  79.1     6.3      M    M
 29000  -46.4 -51.5   305   42   22   8.5   4.6   25.5  77.9     5.9      M    M
 28000  -43.9 -47.0   305   41   21   8.5   4.6   25.0  77.1     5.6      M    M
 27000  -41.4 -42.5   305   39   20   8.5   4.7   24.7  76.4     5.4      M    M
 26000  -38.8 -37.8   305   38   20   8.5   4.7   24.1  75.4     5.0      M    M
 25000  -36.2 -33.2   305   37   19   8.5   4.7   23.7  74.6     4.7      M    M
 24000  -33.7 -28.7   305   37   19   8.6   4.7   23.3  74.7     4.5      M    M
 23000  -31.2 -24.2   305   36   18   8.2   4.5   22.7  72.9     4.0      M    M
 22000  -28.7 -19.7   305   35   18   8.3   4.5   22.2  71.9     3.6      M    M
 21000  -26.3 -15.3   305   34   18   8.3   4.5   21.7  71.1     3.3      M    M
 20000  -23.8 -10.8   300   31   16   8.3   4.5   21.1  70.0     2.8      M    M
 19500  -22.5  -8.5   300   30   15   8.3   4.5   20.8  69.5     2.6      M    M
 19000  -21.3  -6.3   300   29   15   8.3   4.5   20.6  69.1     2.4      M    M
 18500  -20.0  -4.0   300   27   14   8.2   4.5   20.4  68.7     2.2      M    M
 18000  -18.8  -1.8   300   26   13   8.0   4.4   20.1  68.2     2.0      M    M
 17500  -17.6   0.3   300   24   13   8.0   4.4   19.8  67.6     1.7      M    M
 17000  -16.5   2.3   300   23   12   7.2   3.9   19.4  67.0     1.4      M    M
 16500  -15.4   4.3   300   23   12   7.2   4.0   19.0  66.2     1.0      M    M
 16000  -13.8   7.2   305   23   12   6.8   3.7   18.3  65.0     0.5      M    M
 15500  -12.8   9.0   305   24   12   6.8   3.7   17.8  64.1     0.0      M    M
 15000  -11.8  10.8   305   24   12   6.8   3.7   17.3  63.2    -0.4    759  3.9
 14500  -10.8  12.6   305   24   12   6.8   3.7   16.8  62.3    -0.9    714  3.6
 14000   -9.7  14.5   310   23   12   7.1   3.9   16.4  61.4    -1.3    669  3.4
 13500   -8.7  16.3   310   23   12   7.2   3.9   15.9  60.7    -1.7    622  3.2
 13000   -7.6  18.3   315   23   12   6.6   3.6   15.5  59.9    -2.2    576  2.9
 12500   -6.7  19.9   315   24   12   6.3   3.5   14.9  58.9    -2.7    533  2.7
 12000   -5.8  21.6   315   24   12   5.7   3.1   14.4  57.9    -3.3    490  2.5
 11500   -5.0  23.0   315   24   12   5.2   2.9   13.6  56.5    -4.0    453  2.3
 11000   -4.3  24.3   315   24   12   6.1   3.3   12.9  55.3    -4.7    416  2.1
 10500   -3.3  26.1   315   25   13   7.2   3.9   12.4  54.3    -5.3    372  1.9
 10250   -2.8  27.0   315   25   13   4.7   2.6   12.2  53.9    -5.5    351  1.8
 10000   -2.6  27.3   315   26   13   3.6   2.0   11.7  53.0    -6.1    336  1.7
  9750   -2.2  28.0   315   26   13   6.6   3.6   11.3  52.4    -6.4    318  1.6
  9500   -1.7  28.9   310   27   14   7.4   4.1   11.1  52.0    -6.7    296  1.5
  9250   -1.2  29.8   310   28   14   6.3   3.4   10.9  51.6    -6.9    273  1.4
  9000   -0.9  30.4   305   27   14   4.6   2.5   10.5  51.0    -7.3    255  1.3
  8750   -0.6  30.9   305   27   14   5.4   2.9   10.2  50.3    -7.8    238  1.2
  8500   -0.2  31.6   305   25   13   5.9   3.2    9.8  49.7    -8.1    219  1.1
  8250    0.2  32.4   305   24   12   6.4   3.5    9.6  49.2    -8.5    199  1.0
  8000    0.7  33.3   305   22   11   7.1   3.9    9.3  48.8    -8.7    177  0.9
  7750    1.3  34.3   305   20   10   7.2   4.0    9.1  48.4    -9.0    154  0.8
  7500    1.8  35.2   305   18   10   7.8   4.3    9.0  48.1    -9.2    130  0.7
  7250    2.4  36.3   305   17    9   8.5   4.7    8.8  47.9    -9.3    105  0.5
  7000    3.0  37.4   305   15    8   8.7   4.8    8.8  47.8    -9.4     78  0.4
  6750    3.7  38.7   305   14    7   9.2   5.0    8.7  47.6    -9.5     51  0.3
  6500    4.3  39.7   310   12    6   5.7   3.1    8.6  47.4    -9.7     26  0.1
  6250    4.5  40.1   315   10    5   1.7   0.9    8.1  46.5   -10.2     12  0.1
  6000    4.7  40.5   320    9    5   5.1   2.8    7.5  45.6   -10.8      M    M
  5750    4.9  40.8   330    7    4  -4.5  -2.5    7.0  44.6   -11.3      M    M
  5500    3.4  38.1   325    4    2 -38.4 -21.1    4.8  40.6   -13.6     24  0.1

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

           03/22/2024 at 0900 MDT          |       03/22/2024 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +5.8        | CAPE...     0.0    LI...       +3.5
CINH...     0.0    K Index... -10.4        | CINH...     0.0    K Index...  -8.8
                                           |
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 -57.1 -70.8  290  46 24   2.3   1.3 | -57.0 -70.6  285  47 24   2.2   1.2
 45000 -53.4 -64.1  295  51 26   2.8   1.6 | -53.5 -64.3  290  53 27   2.7   1.5
 40000 -59.1 -74.4  295  52 27  -4.2  -2.3 | -58.9 -74.0  290  52 27  -4.0  -2.2
 38000 -60.6 -77.1  295  52 27   1.2   0.7 | -60.4 -76.7  295  51 26   1.2   0.6
 36000 -59.8 -75.6  300  51 26   1.3   0.7 | -59.6 -75.3  290  49 25   1.3   0.7
 34000 -59.1 -74.4  300  49 25   4.4   2.4 | -58.8 -73.8  290  48 25   4.4   2.4
 32000 -53.6 -64.5  300  46 24   8.1   4.5 | -53.5 -64.3  285  46 24   7.9   4.4
 30000 -48.7 -55.7  305  43 22   8.4   4.6 | -48.7 -55.7  285  45 23   8.5   4.6
 29000 -46.2 -51.2  305  41 21   8.4   4.6 | -46.1 -51.0  290  45 23   8.5   4.6
 28000 -43.6 -46.5  305  40 20   8.4   4.6 | -43.6 -46.5  290  44 23   8.5   4.6
 27000 -41.1 -42.0  305  38 20   8.5   4.6 | -41.0 -41.8  290  44 23   8.5   4.7
 26000 -38.5 -37.3  305  37 19   8.6   4.7 | -38.5 -37.3  290  43 22   8.5   4.7
 25000 -35.9 -32.6  305  36 19   8.7   4.7 | -35.9 -32.6  290  42 22   8.5   4.7
 24000 -33.4 -28.1  305  35 18   8.7   4.8 | -33.4 -28.1  290  41 21   8.5   4.7
 23000 -30.7 -23.3  305  35 18   8.7   4.8 | -30.9 -23.6  295  39 20   8.2   4.5
 22000 -28.1 -18.6  305  34 18   8.7   4.8 | -28.4 -19.1  295  37 19   8.2   4.5
 21000 -25.5 -13.9  305  34 17   8.3   4.5 | -25.9 -14.6  300  34 18   8.2   4.5
 20000 -23.1  -9.6  305  33 17   8.0   4.4 | -23.5 -10.3  305  34 17   8.2   4.5
 19500 -21.9  -7.4  305  33 17   8.0   4.4 | -22.3  -8.1  305  33 17   8.2   4.5
 19000 -20.7  -5.3  310  32 17   8.0   4.4 | -21.0  -5.8  310  33 17   8.2   4.5
 18500 -19.6  -3.3  310  32 17   7.8   4.3 | -19.8  -3.6  310  33 17   8.1   4.4
 18000 -18.4  -1.1  310  31 16   7.6   4.2 | -18.6  -1.5  310  32 16   8.0   4.4
 17500 -17.3   0.9  310  31 16   7.6   4.2 | -17.4   0.7  310  31 16   8.0   4.4
 17000 -16.1   3.0  310  30 15   7.4   4.1 | -16.2   2.8  315  30 15   8.1   4.4
 16500 -15.0   5.0  310  29 15   7.4   4.1 | -15.0   5.0  315  29 15   8.1   4.4
 16000 -13.4   7.9  310  27 14   6.4   3.5 | -13.3   8.1  315  27 14   7.4   4.1
 15500 -12.5   9.5  310  26 13   6.6   3.6 | -12.2  10.0  315  25 13   7.5   4.1
 15000 -11.5  11.3  310  24 12   6.0   3.3 | -11.1  12.0  310  24 12   6.4   3.5
 14500 -10.6  12.9  310  23 12   6.0   3.3 | -10.2  13.6  310  22 11   6.5   3.6
 14000  -9.7  14.5  310  21 11   6.0   3.3 |  -9.2  15.4  310  20 10   5.6   3.1
 13500  -8.8  16.2  315  20 10   6.0   3.3 |  -8.4  16.9  305  19 10   5.5   3.0
 13000  -8.0  17.6  315  19 10   4.4   2.4 |  -7.6  18.3  305  17  9   5.0   2.7
 12500  -7.5  18.5  320  18  9   3.8   2.1 |  -6.9  19.6  300  15  8   4.8   2.6
 12000  -6.9  19.6  330  17  9   5.8   3.2 |  -6.2  20.8  300  13  7   4.9   2.7
 11500  -5.8  21.6  335  18  9   6.9   3.8 |  -5.5  22.1  305  11  6   4.8   2.6
 11000  -4.8  23.4  340  18  9   6.9   3.8 |  -4.8  23.4  310  10  5   6.7   3.7
 10500  -3.9  25.0  340  17  9   7.6   4.2 |  -3.7  25.3  315   9  4   8.2   4.5
 10250  -3.4  25.9  340  17  9   4.1   2.3 |  -3.2  26.2  320   8  4   3.6   2.0
 10000  -3.2  26.2  340  16  8   4.1   2.2 |  -3.0  26.6  320   8  4   4.9   2.7
  9750  -2.7  27.1  340  16  8   9.2   5.0 |  -2.3  27.9  320   8  4  11.2   6.2
  9500  -2.0  28.4  340  15  8   9.8   5.4 |  -1.6  29.1  320   7  4  10.9   6.0
  9250  -1.3  29.7  335  14  7   8.7   4.8 |  -0.8  30.6  315   7  4   9.1   5.0
  9000  -0.7  30.7  330  14  7   7.4   4.1 |  -0.2  31.6  315   7  4   7.2   4.0
  8750  -0.1  31.8  325  15  8   7.9   4.3 |   0.4  32.7  310   7  4   9.2   5.1
  8500   0.5  32.9  320  17  9   8.5   4.7 |   1.1  34.0  305   8  4   9.8   5.4
  8250   1.0  33.8  315  19 10   5.7   3.1 |   1.7  35.1  305   8  4   7.3   4.0
  8000   1.3  34.3  310  20 10   3.5   1.9 |   2.1  35.8  305   7  4   5.7   3.2
  7750   1.5  34.7  305  21 11   4.1   2.3 |   2.5  36.5  300   6  3   5.6   3.0
  7500   1.8  35.2  305  20 10   5.3   2.9 |   2.9  37.2  300   4  2   6.8   3.7
  7250   2.3  36.1  300  19 10   7.5   4.1 |   3.5  38.3  295   4  2   9.5   5.2
  7000   2.9  37.2  300  18  9   7.9   4.3 |   4.2  39.6  295   3  2   9.6   5.2
  6750   3.5  38.3  300  17  9   8.4   4.6 |   4.9  40.8  290   3  2  10.5   5.8
  6500   4.0  39.2  300  16  8   4.4   2.4 |   5.8  42.4  290   3  2  11.2   6.1
  6250   4.1  39.4  300  13  7   0.3   0.2 |   6.6  43.9  290   3  2  10.9   6.0
  6000   4.2  39.6  295  11  5   2.8   1.5 |   7.4  45.3  290   3  1  10.2   5.6
  5750   4.3  39.7  290   8  4  -3.1  -1.7 |   8.2  46.8  290   3  1  13.2   7.3
  5500   3.3  37.9  280   4  2 -21.4 -11.8 |   9.5  49.1  290   3  1  22.2  12.2

           03/22/2024 at 1500 MDT          |       03/22/2024 at 1800 MDT
                                           |
CAPE...     0.0    LI...       +2.4        | CAPE...    +0.1    LI...       -0.3
CINH...    -0.1    K Index...  -5.6        | CINH...    -0.3    K Index... +17.1
                                           |
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 -57.6 -71.7  280  52 27   2.3   1.2 | -56.9 -70.4  280  54 28   1.8   1.0
 45000 -54.0 -65.2  285  64 33   2.8   1.5 | -54.1 -65.4  285  60 31   2.2   1.2
 40000 -58.8 -73.8  285  60 31  -3.6  -2.0 | -59.3 -74.7  285  63 33  -3.8  -2.1
 38000 -60.0 -76.0  285  57 29   1.3   0.7 | -60.6 -77.1  280  63 32   1.6   0.9
 36000 -59.2 -74.6  285  53 27   1.3   0.7 | -59.5 -75.1  285  58 30   1.7   1.0
 34000 -58.4 -73.1  285  49 25   4.2   2.3 | -58.5 -73.3  285  53 27   4.2   2.3
 32000 -53.5 -64.3  290  48 25   7.3   4.0 | -53.6 -64.5  285  51 26   7.3   4.0
 30000 -48.9 -56.0  290  47 24   8.8   4.8 | -49.1 -56.4  285  48 25   8.9   4.9
 29000 -46.3 -51.3  295  47 24   8.8   4.8 | -46.4 -51.5  285  46 24   8.8   4.8
 28000 -43.7 -46.7  295  46 24   8.8   4.8 | -43.8 -46.8  285  44 22   8.8   4.8
 27000 -41.1 -42.0  300  46 24   8.6   4.7 | -41.2 -42.2  290  41 21   8.7   4.8
 26000 -38.5 -37.3  300  43 22   8.4   4.6 | -38.6 -37.5  290  41 21   8.5   4.6
 25000 -36.0 -32.8  300  41 21   8.4   4.6 | -36.1 -33.0  290  41 21   8.5   4.6
 24000 -33.5 -28.3  300  38 20   8.3   4.6 | -33.6 -28.5  290  41 21   8.4   4.6
 23000 -31.0 -23.8  300  36 19   8.2   4.5 | -31.2 -24.2  285  38 20   7.7   4.2
 22000 -28.6 -19.5  300  34 18   8.2   4.5 | -28.9 -20.0  285  34 18   7.7   4.2
 21000 -26.1 -15.0  295  32 17   8.3   4.6 | -26.6 -15.9  285  31 16   8.2   4.5
 20000 -23.6 -10.5  295  31 16   8.3   4.6 | -24.1 -11.4  285  30 16   8.4   4.6
 19500 -22.3  -8.1  295  31 16   8.3   4.6 | -22.8  -9.0  280  30 15   8.4   4.6
 19000 -21.1  -6.0  295  30 16   8.3   4.6 | -21.6  -6.9  280  30 15   8.4   4.6
 18500 -19.8  -3.6  295  30 15   8.1   4.4 | -20.3  -4.5  280  29 15   8.0   4.4
 18000 -18.7  -1.7  300  30 15   7.9   4.3 | -19.2  -2.6  280  29 15   7.6   4.2
 17500 -17.5   0.5  300  29 15   7.9   4.3 | -18.0  -0.4  275  28 14   7.6   4.1
 17000 -16.3   2.7  300  28 15   7.7   4.2 | -16.8   1.8  275  27 14   8.3   4.6
 16500 -15.2   4.6  300  27 14   7.7   4.2 | -15.6   3.9  275  27 14   8.3   4.5
 16000 -14.0   6.8  300  26 13   8.2   4.5 | -13.7   7.3  270  26 13   9.3   5.1
 15500 -12.1  10.2  300  25 13   8.4   4.6 | -12.3   9.9  270  25 13   9.4   5.2
 15000 -10.9  12.4  300  24 12   7.9   4.4 | -11.0  12.2  270  24 12   8.4   4.6
 14500  -9.7  14.5  300  22 11   8.1   4.4 |  -9.7  14.5  270  22 11   8.5   4.7
 14000  -8.6  16.5  295  21 11   7.1   3.9 |  -8.5  16.7  265  20 10   8.7   4.8
 13500  -7.5  18.5  290  20 10   7.1   3.9 |  -7.2  19.0  265  18  9   8.7   4.8
 13000  -6.5  20.3  285  19 10   7.0   3.8 |  -6.0  21.2  265  16  8   7.9   4.3
 12500  -5.5  22.1  280  17  9   7.0   3.8 |  -4.9  23.2  255  14  7   7.8   4.3
 12000  -4.4  24.1  275  16  8   7.2   4.0 |  -3.8  25.2  250  12  6   7.7   4.2
 11500  -3.4  25.9  270  14  7   7.4   4.1 |  -2.7  27.1  245  11  5   7.6   4.2
 11000  -2.4  27.7  270  12  6   6.4   3.5 |  -1.5  29.3  240   9  5   7.9   4.3
 10500  -1.5  29.3  270   9  5   6.5   3.5 |  -0.4  31.3  225   8  4   8.7   4.8
 10250  -1.1  30.0  270   8  4   3.9   2.1 |   0.2  32.4  215   8  4   4.8   2.6
 10000  -0.9  30.4  275   7  4   4.6   2.5 |   0.5  32.9  210   7  4   4.7   2.6
  9750  -0.4  31.3  265   5  3   7.6   4.2 |   1.1  34.0  205   7  3   8.6   4.7
  9500   0.2  32.4  245   4  2   6.9   3.8 |   1.7  35.1  200   6  3   7.7   4.2
  9250   0.7  33.3  215   3  2   6.7   3.7 |   2.3  36.1  190   6  3   7.5   4.1
  9000   1.2  34.2  200   3  2   7.0   3.9 |   2.8  37.0  185   5  3   7.3   4.0
  8750   1.7  35.1  195   3  2   8.5   4.6 |   3.4  38.1  180   5  2   7.7   4.2
  8500   2.3  36.1  185   3  2   8.7   4.8 |   4.0  39.2  175   4  2   7.8   4.3
  8250   3.0  37.4  180   4  2   9.3   5.1 |   4.6  40.3  170   3  2   7.7   4.2
  8000   3.7  38.7  180   4  2   9.9   5.4 |   5.1  41.2  170   3  1   7.9   4.3
  7750   4.4  39.9  180   4  2   9.7   5.3 |   5.7  42.3  165   2  1   8.3   4.6
  7500   5.1  41.2  180   4  2   9.9   5.5 |   6.3  43.3  165   2  1   9.0   4.9
  7250   5.9  42.6  180   4  2  10.3   5.7 |   7.0  44.6  165   2  1   9.9   5.4
  7000   6.7  44.1  180   4  2  10.6   5.8 |   7.8  46.0  165   2  1  10.4   5.7
  6750   7.4  45.3  180   4  2   9.5   5.2 |   8.5  47.3  170   1  1   9.3   5.1
  6500   8.1  46.6  180   4  2   9.9   5.4 |   9.2  48.6  175   1  1   9.4   5.1
  6250   8.9  48.0  180   3  2  11.4   6.3 |   9.9  49.8  180   1  1  10.3   5.6
  6000   9.7  49.5  180   3  2  10.3   5.6 |  10.7  51.3  190   1  0  10.0   5.5
  5750  10.6  51.1  180   3  2  13.2   7.2 |  11.4  52.5  200   1  0  10.4   5.7
  5500  11.8  53.2  180   3  2  21.8  12.0 |  12.2  54.0  205   1  0  11.3   6.2
________________________________________________________________________________

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.

CINH (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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