Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 221245
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0644 MDT Friday, March 22, 2024

This forecast is for Friday, March 22, 2024:

If the trigger temperature of 52.1 F/11.1 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 624 ft/min (3.2 m/s)
   Maximum height of thermals.................. 15284 ft MSL (9983 ft AGL)

Forecast maximum temperature................... 63.0 F/17.7 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12891 ft MSL (7591 ft AGL)
Thermal soaring outlook for Saturday 03/23..... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change expected
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 38796 ft MSL (33495 ft AGL)
Wave soaring outlook for Saturday 03/23........ Good

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.................. 8931 ft MSL (3630 ft AGL)
Convective condensation level... 12244 ft MSL (6943 ft AGL)
Lifted condensation level....... 13924 ft MSL (8623 ft AGL)
Lifted index.................... -1.5
K index......................... +6.2

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  -57.7 -71.9   280   45   23   2.3   1.3      M     M       M      M    M
 45000  -54.3 -65.7   280   42   22   2.7   1.5      M     M       M      M    M
 40000  -57.6 -71.7   290   50   26  -2.5  -1.4      M     M       M      M    M
 38000  -58.7 -73.7   295   52   27  -0.1  -0.1      M     M       M      M    M
 36000  -58.7 -73.7   295   51   26  -0.1  -0.0      M     M       M      M    M
 34000  -58.7 -73.7   300   50   26   2.2   1.2      M     M       M      M    M
 32000  -53.9 -65.0   305   46   24   7.4   4.0      M     M       M      M    M
 30000  -49.4 -56.9   305   44   23   8.7   4.8   25.7  78.3     6.4      M    M
 29000  -46.8 -52.2   305   43   22   8.6   4.7   25.1  77.2     6.0      M    M
 28000  -44.3 -47.7   305   42   22   8.6   4.7   24.7  76.4     5.7      M    M
 27000  -41.7 -43.1   305   42   21   8.6   4.7   24.3  75.8     5.5      M    M
 26000  -39.1 -38.4   305   40   21   8.8   4.8   23.9  75.0     5.2      M    M
 25000  -36.4 -33.5   305   38   20   8.8   4.8   23.5  74.3     5.0      M    M
 24000  -33.8 -28.8   300   36   19   8.8   4.8   23.3  73.9     4.9      M    M
 23000  -31.2 -24.2   300   35   18   8.4   4.6   22.7  72.9     4.5      M    M
 22000  -28.7 -19.7   300   35   18   8.4   4.6   22.2  72.0     4.1      M    M
 21000  -26.2 -15.2   300   34   18   8.3   4.6   21.8  71.2     3.8      M    M
 20000  -23.7 -10.7   305   34   18   8.3   4.5   21.2  70.1     3.3      M    M
 19500  -22.5  -8.5   305   34   18   8.3   4.5   20.9  69.7     3.1      M    M
 19000  -21.3  -6.3   305   34   18   8.3   4.5   20.7  69.3     3.0      M    M
 18500  -20.0  -4.0   305   34   18   8.1   4.4   20.5  68.9     2.8      M    M
 18000  -18.8  -1.8   305   33   17   7.7   4.2   20.1  68.2     2.5      M    M
 17500  -17.7   0.1   305   33   17   7.8   4.3   19.8  67.6     2.2      M    M
 17000  -16.6   2.1   305   32   16   7.0   3.9   19.4  66.9     1.9      M    M
 16500  -15.0   5.0   305   30   15   7.1   3.9   18.7  65.7     1.3      M    M
 16000  -14.1   6.6   300   29   15   5.7   3.1   18.1  64.6     0.7      M    M
 15500  -13.2   8.2   300   28   14   5.9   3.2   17.5  63.5     0.1      M    M
 15000  -12.3   9.9   305   27   14   5.9   3.3   16.8  62.3    -0.5    793  4.0
 14500  -11.5  11.3   305   27   14   6.0   3.3   16.2  61.2    -1.1    752  3.8
 14000  -10.6  12.9   305   26   14   5.9   3.2   15.6  60.0    -1.7    711  3.6
 13500   -9.8  14.4   305   26   14   5.9   3.2   14.9  58.9    -2.3    672  3.4
 13000   -8.9  16.0   305   26   13   6.2   3.4   14.3  57.8    -2.9    631  3.2
 12500   -8.0  17.6   305   25   13   6.4   3.5   13.8  56.8    -3.5    589  3.0
 12000   -7.1  19.2   310   24   12   7.0   3.9   13.2  55.8    -4.1    546  2.8
 11500   -6.0  21.2   310   23   12   7.4   4.0   12.9  55.1    -4.5    499  2.5
 11000   -4.9  23.2   310   22   11   8.2   4.5   12.5  54.5    -4.8    451  2.3
 10500   -3.6  25.5   315   22   11   9.2   5.0   12.3  54.1    -5.1    398  2.0
 10250   -3.0  26.6   315   22   11   5.9   3.2   12.2  54.0    -5.2    372  1.9
 10000   -2.7  27.1   315   22   11   5.5   3.0   11.8  53.2    -5.6    355  1.8
  9750   -2.1  28.2   310   21   11   9.6   5.3   11.7  53.0    -5.8    330  1.7
  9500   -1.4  29.5   310   19   10  10.2   5.6   11.7  53.0    -5.8    301  1.5
  9250   -0.6  30.9   310   18    9   8.6   4.7   11.7  53.0    -5.8    272  1.4
  9000   -0.1  31.8   305   17    9   6.4   3.5   11.5  52.7    -6.0    249  1.3
  8750    0.4  32.7   305   15    8   7.0   3.8   11.2  52.2    -6.3    227  1.2
  8500    0.9  33.6   300   14    7   7.6   4.1   11.0  51.9    -6.5    204  1.0
  8250    1.4  34.5   295   12    6   6.4   3.5   10.8  51.5    -6.7    180  0.9
  8000    1.8  35.2   290   11    6   5.4   3.0   10.5  51.0    -7.1    161  0.8
  7750    2.2  36.0   285   10    5   5.6   3.1   10.2  50.4    -7.4    141  0.7
  7500    2.6  36.7   285    8    4   5.2   2.8    9.9  49.8    -7.8    122  0.6
  7250    3.0  37.4   280    6    3   4.6   2.5    9.5  49.1    -8.2    104  0.5
  7000    3.3  37.9   280    4    2   4.4   2.4    9.1  48.4    -8.6     86  0.4
  6750    3.7  38.7   275    2    1   4.2   2.3    8.7  47.6    -9.0     69  0.4
  6500    3.9  39.0   000    0    0   2.4   1.3    8.2  46.8    -9.5     54  0.3
  6250    4.0  39.2   180    2    1   0.6   0.4    7.6  45.6   -10.2     44  0.2
  6000    4.1  39.4   180    3    1   3.1   1.7    6.9  44.5   -10.8     34  0.2
  5750    4.2  39.6   185    4    2  -4.8  -2.7    6.3  43.4   -11.5     23  0.1
  5500    2.9  37.2   190    5    2 -29.4 -16.2    4.3  39.8   -13.6     55  0.3

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

           03/22/2024 at 0900 MDT          |       03/22/2024 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +4.5        | CAPE...     0.0    LI...       +2.9
CINH...     0.0    K Index...  -2.6        | CINH...     0.0    K Index...  -4.4
                                           |
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 -56.8 -70.2  285  43 22   2.2   1.2 | -56.3 -69.3  285  46 24   2.2   1.2
 45000 -53.3 -63.9  285  43 22   2.8   1.5 | -53.1 -63.6  290  53 27   2.6   1.4
 40000 -59.6 -75.3  295  46 23  -4.6  -2.5 | -59.6 -75.3  290  49 25  -4.8  -2.7
 38000 -61.2 -78.2  295  47 24   1.9   1.1 | -61.3 -78.3  285  48 25   2.0   1.1
 36000 -59.9 -75.8  295  48 25   2.1   1.1 | -60.0 -76.0  290  48 25   2.2   1.2
 34000 -58.7 -73.7  295  49 25   4.6   2.5 | -58.1 -72.6  290  48 25   8.1   4.4
 32000 -53.6 -64.5  300  47 24   7.7   4.2 | -53.5 -64.3  290  44 23   7.7   4.2
 30000 -48.9 -56.0  305  45 23   8.6   4.7 | -48.8 -55.8  290  42 21   8.5   4.7
 29000 -46.3 -51.3  305  45 23   8.6   4.7 | -46.2 -51.2  290  43 22   8.4   4.6
 28000 -43.7 -46.7  305  44 23   8.6   4.7 | -43.7 -46.7  290  44 23   8.4   4.6
 27000 -41.2 -42.2  305  44 23   8.6   4.7 | -41.2 -42.2  290  46 23   8.5   4.7
 26000 -38.6 -37.5  305  43 22   8.6   4.7 | -38.6 -37.5  290  45 23   8.7   4.8
 25000 -36.0 -32.8  305  42 22   8.6   4.7 | -36.0 -32.8  290  45 23   8.7   4.8
 24000 -33.5 -28.3  305  42 21   8.5   4.7 | -33.4 -28.1  290  44 23   8.6   4.7
 23000 -31.0 -23.8  305  40 21   8.3   4.5 | -31.0 -23.8  290  42 22   7.7   4.2
 22000 -28.5 -19.3  305  39 20   8.3   4.5 | -28.7 -19.7  295  39 20   7.8   4.3
 21000 -26.0 -14.8  305  38 20   8.2   4.5 | -26.3 -15.3  295  37 19   7.9   4.3
 20000 -23.6 -10.5  305  37 19   8.1   4.5 | -23.9 -11.0  300  35 18   8.0   4.4
 19500 -22.4  -8.3  305  36 19   8.1   4.5 | -22.7  -8.9  300  35 18   8.0   4.4
 19000 -21.2  -6.2  305  36 18   8.2   4.5 | -21.5  -6.7  305  35 18   8.0   4.4
 18500 -19.9  -3.8  305  35 18   8.2   4.5 | -20.3  -4.5  305  34 18   8.0   4.4
 18000 -18.7  -1.7  305  34 18   8.2   4.5 | -19.1  -2.4  305  33 17   8.0   4.4
 17500 -17.5   0.5  305  33 17   8.3   4.5 | -17.9  -0.2  310  33 17   7.9   4.3
 17000 -16.3   2.7  305  33 17   7.7   4.2 | -16.0   3.2  310  31 16   8.8   4.9
 16500 -14.5   5.9  305  31 16   7.7   4.2 | -14.7   5.5  310  30 15   8.8   4.8
 16000 -13.5   7.7  300  30 15   6.7   3.7 | -13.4   7.9  310  28 14   8.3   4.5
 15500 -12.4   9.7  300  29 15   6.9   3.8 | -12.2  10.0  305  26 13   8.5   4.6
 15000 -11.5  11.3  300  27 14   5.1   2.8 | -11.0  12.2  305  24 12   6.7   3.7
 14500 -10.8  12.6  300  25 13   5.3   2.9 | -10.0  14.0  300  22 11   6.9   3.8
 14000 -10.0  14.0  300  23 12   4.5   2.4 |  -9.1  15.6  300  20 10   5.5   3.0
 13500  -9.4  15.1  305  21 11   4.3   2.4 |  -8.3  17.1  295  18  9   5.3   2.9
 13000  -8.8  16.2  310  19 10   4.9   2.7 |  -7.6  18.3  295  16  8   4.3   2.3
 12500  -8.0  17.6  310  18  9   5.2   2.8 |  -7.0  19.4  295  15  7   3.9   2.2
 12000  -7.3  18.9  315  17  9   6.2   3.4 |  -6.4  20.5  300  13  7   4.6   2.5
 11500  -6.3  20.7  320  16  8   6.7   3.7 |  -5.8  21.6  305  10  5   4.8   2.6
 11000  -5.4  22.3  320  16  8   6.5   3.6 |  -5.0  23.0  310   8  4   7.1   3.9
 10500  -4.4  24.1  320  16  8   7.0   3.9 |  -3.8  25.2  310   7  4   8.9   4.9
 10250  -4.0  24.8  315  15  8   3.9   2.2 |  -3.3  26.1  310   7  4   4.1   2.2
 10000  -3.8  25.2  315  15  8   4.8   2.6 |  -3.1  26.4  305   7  3   4.9   2.7
  9750  -3.2  26.2  315  15  8  10.1   5.5 |  -2.4  27.7  305   8  4  11.2   6.1
  9500  -2.4  27.7  315  15  8  10.9   6.0 |  -1.6  29.1  300   9  5  11.2   6.1
  9250  -1.6  29.1  315  15  8   8.8   4.9 |  -0.8  30.6  295  10  5   8.8   4.8
  9000  -1.1  30.0  315  16  8   6.7   3.7 |  -0.3  31.5  295  10  5   5.7   3.1
  8750  -0.6  30.9  310  17  9   8.3   4.6 |   0.1  32.2  295  10  5   6.8   3.7
  8500   0.1  32.2  310  17  9   9.1   5.0 |   0.6  33.1  295   9  5   7.2   3.9
  8250   0.7  33.3  305  18  9   7.2   3.9 |   1.1  34.0  290   8  4   6.7   3.7
  8000   1.1  34.0  305  16  8   5.9   3.2 |   1.6  34.9  285   6  3   6.4   3.5
  7750   1.6  34.9  300  14  7   6.6   3.6 |   2.1  35.8  270   4  2   7.5   4.1
  7500   2.1  35.8  295  12  6   6.2   3.4 |   2.7  36.9  255   3  2   8.9   4.9
  7250   2.5  36.5  290   9  5   5.4   3.0 |   3.3  37.9  250   3  2   9.4   5.2
  7000   2.9  37.2  275   7  4   5.4   2.9 |   4.0  39.2  245   3  2   9.7   5.3
  6750   3.3  37.9  255   5  2   5.3   2.9 |   4.7  40.5  240   3  1   9.4   5.1
  6500   3.6  38.5  230   4  2   3.6   2.0 |   5.4  41.7  235   3  1  10.3   5.7
  6250   3.8  38.8  215   5  2   2.0   1.1 |   6.3  43.3  235   3  1  11.6   6.4
  6000   4.0  39.2  210   6  3   3.4   1.9 |   7.1  44.8  230   3  1  10.5   5.8
  5750   4.2  39.6  205   7  3  -0.6  -0.4 |   7.9  46.2  230   3  1  13.5   7.4
  5500   3.5  38.3  200   6  3 -15.8  -8.7 |   9.3  48.7  220   3  1  22.1  12.1

           03/22/2024 at 1500 MDT          |       03/22/2024 at 1800 MDT
                                           |
CAPE...    +7.3    LI...       +0.6        | CAPE...  +291.1    LI...       -1.6
CINH...   -40.3    K Index...  +1.6        | CINH...   -42.4    K Index...  +3.0
                                           |
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  280  54 28   2.1   1.2 | -57.5 -71.5  280  55 28   1.8   1.0
 45000 -53.8 -64.8  285  65 33   2.6   1.4 | -54.6 -66.3  290  63 32   2.3   1.3
 40000 -59.3 -74.7  285  60 31  -4.1  -2.3 | -58.6 -73.5  290  65 34  -2.9  -1.6
 38000 -60.7 -77.3  285  57 29   1.7   0.9 | -59.5 -75.1  290  65 33   1.2   0.6
 36000 -59.6 -75.3  290  54 28   1.8   1.0 | -58.8 -73.8  290  60 31   1.2   0.7
 34000 -58.6 -73.5  290  50 26   4.5   2.4 | -58.1 -72.6  290  55 28   4.1   2.2
 32000 -53.4 -64.1  290  50 26   7.7   4.2 | -53.4 -64.1  285  51 26   7.0   3.8
 30000 -48.7 -55.7  290  49 25   8.4   4.6 | -49.0 -56.2  285  47 24   9.2   5.0
 29000 -46.2 -51.2  295  48 25   8.4   4.6 | -46.2 -51.2  290  46 24   9.1   5.0
 28000 -43.7 -46.7  295  47 24   8.4   4.6 | -43.5 -46.3  290  44 23   9.1   5.0
 27000 -41.2 -42.2  295  46 24   8.3   4.6 | -40.8 -41.4  290  42 22   8.6   4.7
 26000 -38.7 -37.7  295  44 23   8.2   4.5 | -38.5 -37.3  290  39 20   7.6   4.1
 25000 -36.3 -33.3  295  43 22   8.2   4.5 | -36.2 -33.2  295  36 19   7.6   4.2
 24000 -33.8 -28.8  295  41 21   8.1   4.5 | -34.0 -29.2  295  33 17   7.6   4.2
 23000 -31.5 -24.7  295  39 20   7.7   4.2 | -31.6 -24.9  295  32 16   8.0   4.4
 22000 -29.2 -20.6  300  37 19   7.7   4.2 | -29.2 -20.6  295  31 16   8.0   4.4
 21000 -26.8 -16.2  300  35 18   8.2   4.5 | -26.8 -16.2  295  30 15   8.4   4.6
 20000 -24.3 -11.7  300  33 17   8.5   4.7 | -24.2 -11.6  290  29 15   8.5   4.7
 19500 -23.0  -9.4  300  32 17   8.5   4.7 | -22.9  -9.2  290  29 15   8.5   4.7
 19000 -21.7  -7.1  300  32 16   8.5   4.7 | -21.6  -6.9  290  28 15   8.6   4.7
 18500 -20.5  -4.9  300  31 16   8.4   4.6 | -20.4  -4.7  285  28 14   8.7   4.8
 18000 -19.2  -2.6  300  30 15   8.3   4.5 | -19.0  -2.2  285  27 14   8.9   4.9
 17500 -18.0  -0.4  300  29 15   8.3   4.5 | -17.7   0.1  285  26 13   8.9   4.9
 17000 -16.2   2.8  300  28 14   8.0   4.4 | -16.4   2.5  285  25 13   8.2   4.5
 16500 -15.0   5.0  295  26 14   8.0   4.4 | -15.2   4.6  285  24 13   8.2   4.5
 16000 -13.8   7.2  295  25 13   8.4   4.6 | -13.3   8.1  285  24 12   8.3   4.6
 15500 -12.5   9.5  295  24 12   8.4   4.6 | -12.1  10.2  285  24 12   8.4   4.6
 15000 -11.3  11.7  295  23 12   8.0   4.4 | -10.8  12.6  285  24 12   8.4   4.6
 14500 -10.1  13.8  290  22 11   8.0   4.4 |  -9.6  14.7  280  25 13   8.5   4.6
 14000  -8.9  16.0  290  21 11   7.8   4.3 |  -8.3  17.1  280  24 13   8.6   4.7
 13500  -7.8  18.0  285  20 10   7.8   4.3 |  -7.1  19.2  280  23 12   8.6   4.7
 13000  -6.6  20.1  280  20 10   7.8   4.3 |  -5.8  21.6  275  22 11   8.7   4.8
 12500  -5.5  22.1  275  19 10   7.9   4.3 |  -4.6  23.7  275  19 10   8.8   4.8
 12000  -4.3  24.3  275  18 10   7.7   4.2 |  -3.3  26.1  270  16  8   8.0   4.4
 11500  -3.3  26.1  270  16  8   7.7   4.2 |  -2.2  28.0  265  13  7   7.7   4.3
 11000  -2.2  28.0  270  15  7   6.8   3.7 |  -1.1  30.0  260  10  5   7.7   4.2
 10500  -1.3  29.7  265  13  6   6.9   3.8 |  -0.0  32.0  240   8  4   8.4   4.6
 10250  -0.9  30.4  265  12  6   4.5   2.4 |   0.5  32.9  225   8  4   4.8   2.6
 10000  -0.6  30.9  265  11  6   5.3   2.9 |   0.7  33.3  220   8  4   5.0   2.7
  9750  -0.1  31.8  260   9  5   8.2   4.5 |   1.3  34.3  210   8  4   8.7   4.8
  9500   0.5  32.9  250   8  4   7.7   4.2 |   1.9  35.4  200   8  4   7.9   4.3
  9250   1.1  34.0  235   6  3   6.8   3.7 |   2.4  36.3  195   8  4   7.6   4.1
  9000   1.5  34.7  220   6  3   6.0   3.3 |   3.0  37.4  190   8  4   7.5   4.1
  8750   2.0  35.6  210   6  3   7.2   3.9 |   3.6  38.5  185   8  4   8.4   4.6
  8500   2.5  36.5  205   6  3   7.3   4.0 |   4.2  39.6  185   8  4   8.7   4.8
  8250   3.1  37.6  195   6  3   8.1   4.5 |   4.8  40.6  185   8  4   8.1   4.4
  8000   3.7  38.7  195   6  3   9.1   5.0 |   5.4  41.7  185   7  4   7.8   4.3
  7750   4.3  39.7  195   6  3   9.3   5.1 |   5.9  42.6  185   7  3   8.6   4.7
  7500   5.1  41.2  195   6  3   9.9   5.4 |   6.6  43.9  185   6  3   9.1   5.0
  7250   5.8  42.4  195   6  3  10.2   5.6 |   7.3  45.1  185   6  3   9.8   5.4
  7000   6.6  43.9  195   6  3  10.6   5.8 |   8.0  46.4  190   6  3  10.2   5.6
  6750   7.3  45.1  195   5  3   9.0   4.9 |   8.8  47.8  190   5  3   9.6   5.3
  6500   8.0  46.4  195   5  3   9.6   5.2 |   9.5  49.1  195   5  3   9.6   5.3
  6250   8.8  47.8  195   5  3  11.6   6.4 |  10.2  50.4  195   5  3  10.2   5.6
  6000   9.6  49.3  195   5  3  10.3   5.7 |  11.0  51.8  200   5  2  10.1   5.5
  5750  10.4  50.7  200   5  3  13.2   7.2 |  11.7  53.1  200   4  2  10.0   5.5
  5500  11.7  53.1  195   5  3  22.0  12.1 |  12.4  54.3  205   4  2  10.4   5.7
________________________________________________________________________________

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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