Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 290114
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1913 MDT Thursday, March 28, 2024

This forecast is for Friday, March 29, 2024:

If the trigger temperature of 53.1 F/11.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 78 ft/min (0.4 m/s)
   Maximum height of thermals.................. 11763 ft MSL (6443 ft AGL)

Forecast maximum temperature................... 59.0 F/15.5 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9418 ft MSL (4098 ft AGL)
Thermal soaring outlook for Saturday 03/30..... Good

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 38624 ft MSL (33304 ft AGL)
Wave soaring outlook for Saturday 03/30........ Good

Remarks...

Sunrise/Sunset.................... 06:46:58 / 19:20:59 MDT
Total possible sunshine........... 12 hr 34 min 1 sec (754 min 1 sec)
Altitude of sun at 13:03:59 MDT... 54.01 degrees

Upper air data from numerical model forecast valid on 03/29/2024 at 0600 MDT

Freezing level.................. 5334 ft MSL (14 ft AGL)
Additional freezing level....... 9173 ft MSL (3853 ft AGL)
Convective condensation level... 13103 ft MSL (7783 ft AGL)
Lifted condensation level....... 12666 ft MSL (7347 ft AGL)
Lifted index.................... +1.4
K index......................... +16.4

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  -60.7 -77.3   250   66   34  -0.7  -0.4      M     M       M      M    M
 45000  -61.8 -79.2   255   70   36  -0.7  -0.4      M     M       M      M    M
 40000  -61.3 -78.3   255   93   48   0.4   0.2      M     M       M      M    M
 38000  -60.1 -76.2   255  100   51   4.6   2.5      M     M       M      M    M
 36000  -57.4 -71.3   250   98   51   4.6   2.5      M     M       M      M    M
 34000  -54.6 -66.3   245   97   50   5.5   3.0      M     M       M      M    M
 32000  -51.0 -59.8   245   89   46   5.9   3.3      M     M       M      M    M
 30000  -47.3 -53.1   245   80   41   8.7   4.8   28.2  82.8     9.9      M    M
 29000  -44.6 -48.3   245   73   38   9.0   5.0   27.8  82.0     9.7      M    M
 28000  -41.9 -43.4   245   67   34   9.1   5.0   27.5  81.5     9.6      M    M
 27000  -39.2 -38.6   240   60   31   9.1   5.0   27.4  81.2     9.6      M    M
 26000  -36.6 -33.9   240   56   29   8.2   4.5   26.8  80.3     9.3      M    M
 25000  -34.2 -29.6   240   53   27   8.2   4.5   26.2  79.1     8.9      M    M
 24000  -31.7 -25.1   240   50   26   8.2   4.5   25.7  78.2     8.6      M    M
 23000  -29.5 -21.1   240   47   24   6.9   3.8   24.8  76.6     8.0      M    M
 22000  -27.4 -17.3   235   43   22   6.8   3.7   23.7  74.7     7.1      M    M
 21000  -25.4 -13.7   235   40   21   6.8   3.7   22.7  72.9     6.4      M    M
 20000  -23.2  -9.8   235   38   19   7.3   4.0   21.8  71.2     5.6      M    M
 19500  -21.6  -6.9   235   36   19   7.3   4.0   21.1  70.0     5.1      M    M
 19000  -20.5  -4.9   240   36   18   7.4   4.0   20.7  69.3     4.8      M    M
 18500  -19.4  -2.9   240   35   18   7.6   4.2   20.3  68.6     4.5      M    M
 18000  -18.3  -0.9   240   35   18   7.9   4.4   20.0  68.0     4.2      M    M
 17500  -17.1   1.2   240   35   18   8.0   4.4   19.7  67.5     3.9      M    M
 17000  -15.9   3.4   245   35   18   7.8   4.3   19.4  66.9     3.6      M    M
 16500  -14.8   5.4   245   35   18   7.8   4.3   19.0  66.3     3.3      M    M
 16000  -13.6   7.5   245   35   18   7.9   4.4   18.7  65.7     3.1      M    M
 15500  -12.4   9.7   245   34   18   8.0   4.4   18.4  65.1     2.8      M    M
 15000  -11.2  11.8   245   33   17   7.8   4.3   18.1  64.6     2.5      M    M
 14500  -10.1  13.8   245   31   16   7.5   4.1   17.8  64.0     2.2      M    M
 14000   -9.0  15.8   245   29   15   7.5   4.1   17.4  63.3     1.8      M    M
 13500   -7.9  17.8   245   27   14   7.7   4.2   17.0  62.6     1.5      M    M
 13000   -6.8  19.8   245   26   13   7.7   4.2   16.7  62.0     1.2      M    M
 12500   -5.8  21.6   250   23   12   6.3   3.5   16.2  61.2     0.7      M    M
 12000   -4.8  23.4   250   19   10   6.5   3.5   15.7  60.3     0.2      M    M
 11500   -3.9  25.0   250   16    8   6.3   3.4   15.2  59.3    -0.3    454  2.3
 11000   -3.0  26.6   255   15    8   6.4   3.5   14.6  58.3    -0.9    411  2.1
 10500   -2.2  28.0   255   13    6   4.7   2.6   13.9  57.1    -1.5    373  1.9
 10250   -1.8  28.8   260   11    6   4.7   2.6   13.5  56.3    -1.9    355  1.8
 10000   -1.4  29.5   260   10    5   6.1   3.3   13.2  55.7    -2.3    336  1.7
  9750   -0.9  30.4   260    9    4   6.4   3.5   12.9  55.3    -2.5    314  1.6
  9500   -0.5  31.1   265    7    4   5.2   2.8   12.6  54.6    -2.9    295  1.5
  9250   -0.2  31.6   270    6    3   5.8   3.2   12.2  54.0    -3.2    275  1.4
  9000    0.2  32.4   275    5    3   4.6   2.5   11.9  53.4    -3.6    256  1.3
  8750    0.6  33.1   280    4    2   4.9   2.7   11.5  52.7    -4.0    239  1.2
  8500    1.0  33.8   295    3    2   6.4   3.5   11.2  52.1    -4.3    219  1.1
  8250    1.4  34.5   320    3    1   5.5   3.0   10.9  51.6    -4.6    198  1.0
  8000    1.9  35.4   350    3    2   7.5   4.1   10.6  51.1    -4.9    178  0.9
  7750    2.5  36.5   025    4    2   8.1   4.5   10.5  50.9    -5.0    151  0.8
  7500    3.0  37.4   035    5    3   6.7   3.7   10.3  50.5    -5.2    129  0.7
  7250    3.5  38.3   040    6    3   7.1   3.9   10.1  50.2    -5.5    106  0.5
  7000    4.1  39.4   040    7    4   8.6   4.7    9.9  49.9    -5.6     81  0.4
  6750    4.7  40.5   040    8    4   6.7   3.7    9.8  49.7    -5.8     55  0.3
  6500    5.1  41.2   040    9    5   6.7   3.7    9.5  49.1    -6.1     36  0.2
  6250    5.5  41.9   040   10    5  -0.5  -0.3    9.2  48.5    -6.5     16  0.1
  6000    5.0  41.0   040    9    5  -7.8  -4.3    8.0  46.3    -7.7     24  0.1
  5750    4.5  40.1   040    7    4  -9.8  -5.4    6.7  44.0    -9.0     34  0.2
  5500    3.0  37.4   055    3    1 -31.0 -17.0    4.5  40.1   -11.2     69  0.4

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

           03/29/2024 at 0900 MDT          |       03/29/2024 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +1.2        | CAPE...     0.0    LI...       +0.9
CINH...     0.0    K Index... +19.4        | CINH...     0.0    K Index... +23.0
                                           |
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 -59.5 -75.1  245  69 36  -0.9  -0.5 | -58.8 -73.8  250  70 36  -0.3  -0.2
 45000 -60.8 -77.4  250  68 35  -0.9  -0.5 | -59.3 -74.7  255  68 35  -0.3  -0.2
 40000 -60.8 -77.4  250  82 42   0.2   0.1 | -59.3 -74.7  245  71 37   0.0   0.0
 38000 -60.1 -76.2  245  88 45   4.5   2.5 | -59.1 -74.4  240  73 38   2.8   1.5
 36000 -57.1 -70.8  245  92 47   4.5   2.5 | -57.3 -71.1  245  79 41   2.6   1.4
 34000 -54.4 -65.9  240  96 49   5.1   2.8 | -55.8 -68.4  250  84 43   3.4   1.8
 32000 -50.9 -59.6  240  85 44   5.7   3.1 | -52.4 -62.3  250  76 39   5.7   3.1
 30000 -47.4 -53.3  240  75 39   7.0   3.8 | -49.0 -56.2  250  68 35   6.9   3.8
 29000 -45.2 -49.4  240  70 36   7.4   4.1 | -46.6 -51.9  250  64 33   8.0   4.4
 28000 -43.0 -45.4  240  64 33   7.4   4.1 | -44.2 -47.6  250  59 30   8.0   4.4
 27000 -40.8 -41.4  240  59 30   7.4   4.1 | -41.8 -43.2  250  55 28   8.0   4.4
 26000 -38.3 -36.9  235  56 29   8.5   4.6 | -39.4 -38.9  250  51 26   8.0   4.4
 25000 -35.8 -32.4  235  53 27   8.5   4.7 | -37.0 -34.6  250  49 25   8.0   4.4
 24000 -33.3 -27.9  235  51 26   8.5   4.7 | -34.5 -30.1  245  46 24   8.1   4.4
 23000 -30.8 -23.4  235  49 25   7.9   4.3 | -32.0 -25.6  245  42 22   8.7   4.8
 22000 -28.5 -19.3  240  47 24   7.9   4.3 | -29.4 -20.9  240  38 20   8.8   4.8
 21000 -26.1 -15.0  250  45 23   8.0   4.4 | -26.8 -16.2  235  35 18   9.0   4.9
 20000 -24.0 -11.2  250  43 22   6.9   3.8 | -24.6 -12.3  240  34 17   6.9   3.8
 19500 -23.0  -9.4  255  42 22   6.9   3.8 | -23.5 -10.3  245  34 17   6.9   3.8
 19000 -21.9  -7.4  255  41 21   7.0   3.8 | -22.0  -7.6  255  35 18   7.0   3.8
 18500 -20.9  -5.6  255  41 21   7.0   3.8 | -21.0  -5.8  265  36 19   7.0   3.8
 18000 -19.4  -2.9  255  39 20   6.4   3.5 | -19.9  -3.8  265  37 19   7.1   3.9
 17500 -18.5  -1.3  255  37 19   6.4   3.5 | -18.9  -2.0  265  38 20   7.1   3.9
 17000 -17.5   0.5  250  35 18   7.4   4.1 | -17.8  -0.0  265  38 20   7.5   4.1
 16500 -16.4   2.5  250  32 17   7.4   4.1 | -16.7   1.9  265  37 19   7.5   4.1
 16000 -15.3   4.5  245  30 15   7.9   4.3 | -15.6   3.9  265  36 18   7.9   4.3
 15500 -14.1   6.6  245  29 15   8.1   4.4 | -14.5   5.9  265  34 17   8.1   4.5
 15000 -12.9   8.8  240  28 14   8.4   4.6 | -13.3   8.1  260  32 16   8.1   4.4
 14500 -11.5  11.3  240  27 14   9.1   5.0 | -12.1  10.2  260  29 15   7.8   4.3
 14000 -10.2  13.6  240  27 14   8.9   4.9 | -10.9  12.4  260  26 13   7.9   4.3
 13500  -9.0  15.8  245  26 14   8.0   4.4 |  -9.8  14.4  255  23 12   7.8   4.3
 13000  -7.8  18.0  245  25 13   8.1   4.4 |  -8.6  16.5  250  21 11   7.9   4.3
 12500  -6.8  19.8  245  21 11   5.8   3.2 |  -7.5  18.5  245  19 10   6.7   3.7
 12000  -5.9  21.4  235  16  8   6.0   3.3 |  -6.5  20.3  240  18  9   7.0   3.9
 11500  -5.1  22.8  230  13  7   5.8   3.2 |  -5.6  21.9  230  17  9   5.0   2.7
 11000  -4.2  24.4  220  12  6   5.9   3.2 |  -4.9  23.2  220  15  8   5.1   2.8
 10500  -3.5  25.7  210  10  5   4.1   2.2 |  -4.0  24.8  200  14  7   6.5   3.5
 10250  -3.2  26.2  195   9  4   3.1   1.7 |  -3.6  25.5  195  13  7   6.2   3.4
 10000  -2.9  26.8  180   8  4   8.9   4.9 |  -3.1  26.4  185  13  7   7.7   4.2
  9750  -2.0  28.4  190   8  4   9.8   5.4 |  -2.4  27.7  175  13  6   7.8   4.3
  9500  -1.6  29.1  180   7  4   5.2   2.8 |  -1.9  28.6  165  11  6   6.6   3.6
  9250  -1.1  30.0  165   7  3   6.1   3.3 |  -1.4  29.5  145  10  5   7.2   3.9
  9000  -0.7  30.7  150   7  3   7.1   3.9 |  -0.8  30.6  130   9  5   6.2   3.4
  8750  -0.1  31.8  130   8  4   8.5   4.6 |  -0.3  31.5  115  10  5   8.0   4.4
  8500   0.6  33.1  125   8  4   8.1   4.5 |   0.4  32.7  110  10  5  10.3   5.7
  8250   1.2  34.2  115   8  4   7.9   4.3 |   1.1  34.0  105  10  5   9.3   5.1
  8000   1.8  35.2  110   8  4   9.2   5.0 |   1.9  35.4  100  10  5  11.2   6.1
  7750   2.5  36.5  100   9  5   7.7   4.2 |   2.7  36.9  100  10  5  10.8   5.9
  7500   3.0  37.4  095   9  5   5.5   3.0 |   3.4  38.1  100  10  5   8.7   4.8
  7250   3.5  38.3  090   9  5   6.0   3.3 |   4.1  39.4  100   9  5   9.5   5.2
  7000   4.0  39.2  090   9  5   6.2   3.4 |   4.9  40.8  095   9  5  10.7   5.9
  6750   4.4  39.9  085   9  5   4.8   2.7 |   5.7  42.3  095   9  5  10.3   5.6
  6500   4.8  40.6  085   8  4   5.3   2.9 |   6.4  43.5  095   9  5   8.7   4.8
  6250   5.1  41.2  090   7  4  -0.2  -0.1 |   7.1  44.8  095   9  5  10.5   5.7
  6000   4.6  40.3  105   5  3  -5.0  -2.8 |   8.0  46.4  095   9  5  12.6   6.9
  5750   4.2  39.6  140   4  2  -5.2  -2.9 |   8.9  48.0  090   9  5  10.2   5.6
  5500   3.4  38.1  175   5  3 -15.6  -8.5 |   9.6  49.3  090   8  4  13.0   7.1

           03/29/2024 at 1500 MDT          |       03/29/2024 at 1800 MDT
                                           |
CAPE...     0.0    LI...       +0.9        | CAPE...     0.0    LI...       +0.8
CINH...     0.0    K Index... +23.6        | CINH...     0.0    K Index... +24.6
                                           |
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 -58.7 -73.7  255  73 37   0.2   0.1 | -58.8 -73.8  255  71 36  -0.0  -0.0
 45000 -58.4 -73.1  250  81 42   0.2   0.1 | -58.9 -74.0  255  77 40  -0.0  -0.0
 40000 -58.6 -73.5  255  84 43  -0.2  -0.1 | -60.5 -76.9  270  98 50  -1.2  -0.7
 38000 -58.3 -72.9  260  84 43   1.8   1.0 | -60.4 -76.7  275 107 55   3.2   1.8
 36000 -57.2 -71.0  260  84 43   1.9   1.0 | -58.5 -73.3  275 114 58   3.3   1.8
 34000 -56.1 -69.0  265  83 43   2.4   1.3 | -56.5 -69.7  270 120 62   4.6   2.5
 32000 -53.2 -63.8  260  76 39   5.0   2.7 | -52.3 -62.1  270 107 55   7.0   3.8
 30000 -50.2 -58.4  260  69 35   6.6   3.6 | -48.2 -54.8  270  93 48   7.4   4.0
 29000 -47.7 -53.9  260  67 34   8.4   4.6 | -45.9 -50.6  270  87 45   7.5   4.1
 28000 -45.2 -49.4  260  65 33   8.5   4.6 | -43.7 -46.7  265  81 42   7.5   4.1
 27000 -42.7 -44.9  260  63 32   8.5   4.6 | -41.4 -42.5  265  75 39   7.5   4.1
 26000 -40.1 -40.2  260  59 30   8.4   4.6 | -39.1 -38.4  265  68 35   8.0   4.4
 25000 -37.6 -35.7  255  52 27   8.4   4.6 | -36.7 -34.1  260  62 32   8.1   4.4
 24000 -35.1 -31.2  250  47 24   8.4   4.6 | -34.2 -29.6  260  55 29   8.1   4.4
 23000 -32.6 -26.7  245  42 22   8.6   4.7 | -31.8 -25.2  255  50 26   8.3   4.5
 22000 -30.0 -22.0  245  38 20   8.7   4.7 | -28.7 -19.7  260  43 22   8.3   4.6
 21000 -26.8 -16.2  235  34 18   8.7   4.8 | -26.2 -15.2  260  37 19   8.4   4.6
 20000 -24.2 -11.6  245  35 18   8.7   4.8 | -23.7 -10.7  255  33 17   8.5   4.7
 19500 -22.9  -9.2  245  36 18   8.7   4.8 | -22.4  -8.3  255  32 16   8.6   4.7
 19000 -21.6  -6.9  250  37 19   8.7   4.8 | -21.2  -6.2  250  30 15   8.6   4.7
 18500 -20.3  -4.5  255  38 19   8.5   4.7 | -19.9  -3.8  250  28 14   8.5   4.7
 18000 -19.2  -2.6  255  37 19   7.8   4.3 | -18.7  -1.7  245  27 14   8.4   4.6
 17500 -18.0  -0.4  255  36 19   7.9   4.3 | -17.4   0.7  245  27 14   8.5   4.7
 17000 -16.8   1.8  255  34 18   7.8   4.3 | -16.2   2.8  245  26 13   7.7   4.2
 16500 -15.7   3.7  255  32 16   7.8   4.3 | -15.1   4.8  245  24 12   7.7   4.2
 16000 -14.5   5.9  255  30 15   7.7   4.2 | -14.0   6.8  245  22 11   7.3   4.0
 15500 -13.4   7.9  255  28 14   7.6   4.2 | -13.0   8.6  245  21 11   7.1   3.9
 15000 -12.3   9.9  250  26 13   7.4   4.0 | -11.9  10.6  245  20 10   7.0   3.9
 14500 -11.3  11.7  250  24 12   6.7   3.7 | -10.9  12.4  245  19 10   6.9   3.8
 14000 -10.3  13.5  245  22 11   6.7   3.7 |  -9.9  14.2  245  17  9   6.9   3.8
 13500  -9.4  15.1  240  20 10   6.6   3.6 |  -8.9  16.0  245  16  8   6.2   3.4
 13000  -8.4  16.9  235  19 10   6.7   3.7 |  -8.0  17.6  245  15  8   6.3   3.4
 12500  -7.5  18.5  225  17  9   6.0   3.3 |  -7.1  19.2  245  14  7   6.5   3.6
 12000  -6.6  20.1  215  14  7   6.1   3.4 |  -6.2  20.8  235  12  6   6.6   3.6
 11500  -5.7  21.7  205  11  6   5.9   3.2 |  -5.3  22.5  225  11  6   5.7   3.1
 11000  -4.8  23.4  185   6  3   5.8   3.2 |  -4.4  24.1  220  10  5   5.9   3.2
 10500  -3.8  25.2  135   3  2   7.1   3.9 |  -3.6  25.5  205   8  4   5.0   2.7
 10250  -3.3  26.1  105   3  2   7.0   3.9 |  -3.2  26.2  185   7  4   5.4   2.9
 10000  -2.7  27.1  080   4  2   8.6   4.7 |  -2.9  26.8  165   7  3   4.0   2.2
  9750  -2.0  28.4  075   4  2  10.6   5.8 |  -2.6  27.3  150   5  3   3.7   2.0
  9500  -1.2  29.8  075   4  2  10.7   5.9 |  -2.3  27.9  125   4  2   4.6   2.5
  9250  -0.4  31.3  070   4  2  11.3   6.2 |  -2.0  28.4  090   4  2   4.8   2.6
  9000   0.4  32.7  065   4  2   8.8   4.8 |  -1.6  29.1  065   5  3   3.1   1.7
  8750   1.0  33.8  060   5  2   8.4   4.6 |  -1.4  29.5  055   6  3   5.4   2.9
  8500   1.8  35.2  055   5  2  10.9   6.0 |  -0.8  30.6  045   7  4   9.0   5.0
  8250   2.5  36.5  055   5  2   9.6   5.3 |  -0.2  31.6  040   8  4   7.7   4.2
  8000   3.3  37.9  050   5  3  12.1   6.7 |   0.4  32.7  035   9  5   9.3   5.1
  7750   4.3  39.7  045   5  3  11.0   6.0 |   1.1  34.0  025  11  6   7.3   4.0
  7500   4.9  40.8  045   5  3   7.7   4.2 |   1.5  34.7  020  13  7   4.3   2.4
  7250   5.6  42.1  040   6  3   8.9   4.9 |   1.9  35.4  015  14  7   5.5   3.0
  7000   6.3  43.3  040   6  3  11.9   6.5 |   2.4  36.3  010  16  8  10.0   5.5
  6750   7.2  45.0  035   6  3  11.0   6.0 |   3.2  37.8  005  16  8  10.2   5.6
  6500   7.9  46.2  035   6  3   7.6   4.2 |   3.8  38.8  005  17  9   6.5   3.6
  6250   8.5  47.3  035   6  3  10.0   5.5 |   4.3  39.7  360  17  9   9.7   5.3
  6000   9.4  48.9  030   6  3  12.8   7.0 |   5.2  41.4  360  16  8  13.5   7.4
  5750  10.3  50.5  030   6  3  10.1   5.5 |   6.2  43.2  360  16  8   9.7   5.3
  5500  10.9  51.6  025   6  3   9.1   5.0 |   6.7  44.1  360  15  8   6.4   3.5
________________________________________________________________________________

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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