Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 251333
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0732 MDT Sunday, October 25, 2020

This forecast is for Sunday, October 25, 2020:

If the trigger temperature of 31.3 F/-0.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7253 ft MSL (1968 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....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Monday 10/26....... Poor

Wave Soaring Index............................. Poor
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....................... 23733 ft MSL (18448 ft AGL)
Wave soaring outlook for Monday 10/26.......... Poor

Remarks...

Sunrise/Sunset.................... 07:21:16 / 18:05:35 MDT
Total possible sunshine........... 10 hr 44 min 19 sec (644 min 19 sec)
Altitude of sun at 12:43:26 MDT... 37.64 degrees

Upper air data from rawinsonde observation taken on 10/25/2020 at 0600 MDT

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 19910 ft MSL (14625 ft AGL)
Lifted condensation level....... 7451 ft MSL (2166 ft AGL)
Lifted index.................... +27.1
K index......................... -1.0

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  -62.0 -79.6   255   77   40   1.6   0.9   97.3 207.1    59.6      M    M
 45000  -60.0 -76.0   250   67   35   3.0   1.6   74.6 166.2    50.1      M    M
 40000  -55.8 -68.4   260   86   44   2.8   1.5   57.6 135.8    42.6      M    M
 38000  -55.0 -67.0   255   78   40   0.3   0.2   50.4 122.6    38.8      M    M
 36000  -53.8 -64.8   255   68   35   6.6   3.6   43.6 110.5    35.2      M    M
 34000  -49.6 -57.3   260   69   35   8.1   4.5   41.2 106.1    34.4      M    M
 32000  -44.8 -48.6   260   67   35   8.0   4.4   39.6 103.3    34.2      M    M
 30000  -39.3 -38.7   260   65   33   8.6   4.7   38.5 101.3    34.3      M    M
 29000  -36.7 -34.1   255   62   32   7.8   4.3   38.0 100.5    34.4      M    M
 28000  -34.7 -30.5   255   60   31   6.9   3.8   36.9  98.4    33.9      M    M
 27000  -32.4 -26.3   255   64   33   8.5   4.7   36.1  97.0    33.7      M    M
 26000  -29.9 -21.8   260   67   35   5.3   2.9   35.5  95.9    33.6      M    M
 25000  -28.6 -19.5   260   71   37   4.6   2.5   33.5  92.4    32.5      M    M
 24000  -27.2 -17.0   260   75   39   5.5   3.0   31.6  88.8    31.3      M    M
 23000  -25.7 -14.3   260   75   39   4.4   2.4   29.8  85.7    30.2      M    M
 22000  -24.2 -11.6   265   74   38   7.8   4.3   28.1  82.6    29.1      M    M
 21000  -21.9  -7.4   265   73   38   7.7   4.2   27.4  81.3    28.8      M    M
 20000  -19.8  -3.6   270   72   37   7.0   3.8   26.5  79.6    28.3      M    M
 19500  -18.8  -1.8   270   71   36   7.2   3.9   26.0  78.8    28.1      M    M
 19000  -17.7   0.1   270   69   36   7.2   3.9   25.5  78.0    27.8      M    M
 18500  -16.7   1.9   270   67   34   7.1   3.9   25.1  77.2    27.6      M    M
 18000  -15.6   3.9   270   64   33   6.9   3.8   24.6  76.3    27.3      M    M
 17500  -14.6   5.7   265   61   31   7.0   3.8   24.1  75.4    27.0      M    M
 17000  -13.6   7.5   265   58   30   7.0   3.8   23.6  74.5    26.7      M    M
 16500  -12.5   9.5   260   56   29   7.0   3.8   23.2  73.7    26.4      M    M
 16000  -11.5  11.3   255   53   28   7.0   3.8   22.8  73.0    26.2      M    M
 15500  -10.5  13.1   255   52   27   7.0   3.9   22.3  72.1    25.9      M    M
 15000   -9.0  15.8   250   49   25   7.1   3.9   21.6  70.8    25.4      M    M
 14500   -8.0  17.6   250   47   24   7.3   4.0   21.1  70.0    25.1      M    M
 14000   -7.1  19.2   250   46   24   4.6   2.5   20.5  69.0    24.7      M    M
 13500   -6.4  20.5   245   45   23   4.5   2.5   19.6  67.4    24.0      M    M
 13000   -5.7  21.7   240   44   23   4.5   2.5   18.8  65.8    23.3      M    M
 12500   -5.1  22.8   240   43   22   4.5   2.5   18.0  64.3    22.7      M    M
 12000   -4.4  24.1   235   42   21   3.8   2.1   17.1  62.9    22.0      M    M
 11500   -3.8  25.2   230   33   17  -6.0  -3.3   16.3  61.3    21.3      M    M
 11000   -7.8  18.0   225   25   13 -52.4 -28.8   10.3  50.6    16.0      M    M
 10500  -11.7  10.9   215   18    9   5.1   2.8    4.4  39.9    10.6      M    M
 10250  -11.9  10.6   205   14    7  -4.0  -2.2    3.5  38.2     9.8      M    M
 10000  -12.0  10.4   195   13    6  -1.7  -0.9    2.5  36.6     8.9      M    M
  9750  -12.2  10.0   205   11    6  -2.5  -1.4    1.6  34.8     8.0      M    M
  9500  -12.4   9.7   220    7    4  -2.4  -1.3    0.6  33.1     7.2      M    M
  9250  -12.6   9.3   255    4    2  -2.4  -1.3   -0.3  31.4     6.3      M    M
  9000  -12.7   9.1   310    5    3  -2.4  -1.3   -1.3  29.7     5.4      M    M
  8750  -12.9   8.8   325    5    3  -2.4  -1.3   -2.2  28.0     4.5      M    M
  8500  -13.1   8.4   335    6    3  -2.5  -1.3   -3.2  26.3     3.6      M    M
  8250  -13.3   8.1   345    6    3  -2.3  -1.3   -4.1  24.6     2.7      M    M
  8000  -13.4   7.9   350    7    4  -2.8  -1.5   -5.1  22.9     1.8      M    M
  7750  -13.6   7.5   360    8    4  -1.2  -0.7   -6.0  21.2     0.9      M    M
  7500  -13.5   7.7   005    9    5   4.1   2.2   -6.6  20.0     0.3      M    M
  7250  -13.1   8.4   010   11    5   6.4   3.5   -6.9  19.5     0.0      M    M
  7000  -12.6   9.3   015   12    6   5.6   3.1   -7.2  19.0    -0.3    214  1.1
  6750  -12.2  10.0   015   12    6   6.5   3.6   -7.5  18.4    -0.6    194  1.0
  6500  -11.8  10.8   015   12    6   3.9   2.1   -7.8  17.9    -0.9    173  0.9
  6250  -11.5  11.3   020   11    6   6.6   3.6   -8.3  17.1    -1.3    158  0.8
  6000  -10.7  12.7   020   11    6  11.2   6.1   -8.2  17.2    -1.3    128  0.6
  5750  -10.0  14.0   020   10    5   9.7   5.3   -8.2  17.2    -1.3     98  0.5
  5500   -9.2  15.4   015    8    4  11.2   6.2   -8.2  17.3    -1.3     68  0.3

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

           10/25/2020 at 0900 MDT          |       10/25/2020 at 1200 MDT
                                           |
CAPE...    +5.3    LI...       +7.0        | CAPE...   +11.3    LI...      +12.9
CINH...    -0.1    K Index...  +5.0        | CINH...    -0.0    K Index...  -2.7
                                           |
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 -61.7 -79.1  265  32 17   2.1   1.1 | -60.5 -76.9  260  31 16   2.1   1.1
 45000 -58.4 -73.1  260  36 18   2.1   1.1 | -57.2 -71.0  255  37 19   2.0   1.1
 40000 -55.3 -67.5  255  44 23   2.1   1.1 | -54.3 -65.7  250  47 24   2.0   1.1
 38000 -53.7 -64.7  250  44 23   3.2   1.8 | -53.1 -63.6  250  48 25   2.1   1.2
 36000 -51.8 -61.2  250  40 21   3.2   1.8 | -51.8 -61.2  245  46 24   2.1   1.2
 34000 -49.6 -57.3  245  37 19   7.8   4.3 | -50.3 -58.5  240  45 23   6.8   3.7
 32000 -44.6 -48.3  250  36 19   7.4   4.1 | -45.3 -49.5  245  42 22   7.3   4.0
 30000 -40.2 -40.4  250  36 19   7.4   4.1 | -41.0 -41.8  245  40 21   6.7   3.7
 29000 -38.0 -36.4  255  37 19   7.4   4.1 | -39.0 -38.2  245  40 21   6.7   3.7
 28000 -35.8 -32.4  255  38 19   7.5   4.1 | -37.0 -34.6  250  40 20   6.7   3.7
 27000 -33.5 -28.3  255  38 20   7.1   3.9 | -35.0 -31.0  250  39 20   6.7   3.7
 26000 -31.8 -25.2  255  39 20   5.7   3.1 | -33.0 -27.4  255  38 20   6.6   3.6
 25000 -30.1 -22.2  255  39 20   5.7   3.1 | -31.0 -23.8  255  36 19   6.6   3.6
 24000 -28.4 -19.1  260  39 20   5.6   3.1 | -29.1 -20.4  255  35 18   6.5   3.6
 23000 -26.5 -15.7  260  39 20   6.5   3.6 | -26.9 -16.4  255  34 18   7.8   4.3
 22000 -24.6 -12.3  260  38 19   6.5   3.6 | -24.6 -12.3  255  34 17   7.8   4.3
 21000 -22.7  -8.9  260  37 19   6.8   3.7 | -22.3  -8.1  255  33 17   7.8   4.3
 20000 -20.4  -4.7  260  35 18   7.8   4.3 | -20.0  -4.0  250  32 17   7.8   4.3
 19500 -19.2  -2.6  260  34 18   7.8   4.3 | -18.8  -1.8  250  32 16   7.8   4.3
 19000 -18.1  -0.6  260  34 17   7.8   4.3 | -17.7   0.1  250  31 16   7.8   4.3
 18500 -16.4   2.5  255  33 17   7.5   4.1 | -16.0   3.2  245  30 16   7.5   4.1
 18000 -15.3   4.5  255  31 16   7.2   4.0 | -14.9   5.2  245  30 15   7.2   3.9
 17500 -14.2   6.4  260  30 16   7.3   4.0 | -13.9   7.0  245  30 15   7.2   3.9
 17000 -13.2   8.2  260  29 15   6.7   3.7 | -12.8   9.0  245  29 15   7.1   3.9
 16500 -12.3   9.9  260  28 15   6.7   3.7 | -11.8  10.8  240  28 15   7.1   3.9
 16000 -11.3  11.7  260  27 14   6.7   3.7 | -10.7  12.7  240  28 14   6.6   3.6
 15500 -10.3  13.5  260  26 14   6.8   3.7 |  -9.8  14.4  240  27 14   6.3   3.5
 15000  -9.3  15.3  255  25 13   6.9   3.8 |  -8.9  16.0  235  26 14   6.0   3.3
 14500  -8.3  17.1  255  24 12   7.2   3.9 |  -8.2  17.2  235  25 13   4.9   2.7
 14000  -7.2  19.0  255  22 11   6.9   3.8 |  -7.4  18.7  230  24 13   5.0   2.8
 13500  -6.4  20.5  250  21 11   5.0   2.7 |  -7.0  19.4  225  23 12   1.9   1.0
 13000  -5.7  21.7  250  20 10   5.3   2.9 |  -6.7  19.9  225  21 11   2.9   1.6
 12500  -5.3  22.5  245  18  9   0.4   0.2 |  -6.8  19.8  220  19 10  -5.0  -2.7
 12000  -5.1  22.8  240  17  9   1.7   0.9 |  -7.4  18.7  220  17  9  -3.6  -2.0
 11500  -5.6  21.9  240  15  8  -7.3  -4.0 |  -8.6  16.5  215  13  7 -13.8  -7.6
 11000  -6.5  20.3  235  13  7  -5.8  -3.2 | -10.6  12.9  215  10  5 -13.5  -7.4
 10500  -8.0  17.6  235  10  5 -14.5  -7.9 | -12.6   9.3  215   6  3 -13.7  -7.5
 10250  -9.0  15.8  235   9  5 -14.3  -7.9 | -13.6   7.5  215   5  2 -14.1  -7.7
 10000 -10.0  14.0  235   8  4 -10.7  -5.9 | -14.6   5.7  210   3  2 -12.2  -6.7
  9750 -10.6  12.9  230   8  4  -9.4  -5.1 | -15.2   4.6  205   2  1  -5.7  -3.1
  9500 -11.5  11.3  230   6  3 -14.2  -7.8 | -15.5   4.1  210   1  1  -4.7  -2.6
  9250 -12.6   9.3  235   5  2 -16.0  -8.8 | -16.0   3.2  000   0  0  -7.7  -4.2
  9000 -13.7   7.3  240   3  1 -12.0  -6.6 | -16.5   2.3  010   1  1  -4.9  -2.7
  8750 -14.3   6.3  250   2  1  -5.7  -3.1 | -16.7   1.9  010   2  1   0.1   0.1
  8500 -14.6   5.7  280   1  1  -4.6  -2.5 | -16.5   2.3  010   3  1   3.1   1.7
  8250 -15.0   5.0  340   2  1  -4.2  -2.3 | -16.3   2.7  015   4  2   3.9   2.1
  8000 -15.2   4.6  005   3  1  -1.4  -0.8 | -16.0   3.2  020   4  2   4.1   2.2
  7750 -15.1   4.8  010   4  2   2.2   1.2 | -15.6   3.9  020   5  3   5.4   2.9
  7500 -14.9   5.2  015   5  3   4.8   2.6 | -15.2   4.6  020   5  3   7.1   3.9
  7250 -14.4   6.1  015   6  3   6.8   3.7 | -14.6   5.7  020   6  3   7.9   4.3
  7000 -13.9   7.0  015   6  3   6.9   3.8 | -14.0   6.8  015   6  3   7.5   4.1
  6750 -13.4   7.9  010   6  3   8.1   4.4 | -13.4   7.9  015   6  3   8.8   4.8
  6500 -12.7   9.1  010   6  3   9.8   5.4 | -12.7   9.1  015   6  3  10.1   5.6
  6250 -12.0  10.4  010   6  3   9.7   5.3 | -12.0  10.4  010   6  3   9.8   5.4
  6000 -11.3  11.7  005   6  3   9.1   5.0 | -11.3  11.7  010   6  3   9.1   5.0
  5750 -10.6  12.9  005   6  3  10.8   5.9 | -10.6  12.9  010   6  3  11.4   6.2
  5500  -9.6  14.7  005   5  3  15.7   8.6 |  -9.5  14.9  010   5  3  18.3  10.0

           10/25/2020 at 1500 MDT          |       10/25/2020 at 1800 MDT
                                           |
CAPE...   +16.1    LI...      +18.8        | CAPE...    +6.9    LI...      +21.3
CINH...    -0.1    K Index...  -9.7        | CINH...    -0.3    K Index... -11.4
                                           |
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 -59.7 -75.5  260  30 16   1.9   1.1 | -58.8 -73.8  255  30 15   2.1   1.2
 45000 -56.6 -69.9  255  38 20   2.0   1.1 | -55.5 -67.9  250  38 19   2.2   1.2
 40000 -53.5 -64.3  250  48 25   2.1   1.2 | -52.1 -61.8  245  47 24   2.3   1.2
 38000 -52.3 -62.1  245  50 26   1.6   0.9 | -51.2 -60.2  245  50 26   0.3   0.2
 36000 -51.3 -60.3  245  49 25   1.6   0.9 | -51.0 -59.8  240  50 26   0.3   0.2
 34000 -50.3 -58.5  240  48 25   4.7   2.6 | -50.8 -59.4  240  50 26   2.5   1.4
 32000 -46.0 -50.8  240  44 23   6.3   3.5 | -47.0 -52.6  235  47 24   5.7   3.1
 30000 -42.1 -43.8  240  41 21   6.8   3.7 | -43.5 -46.3  230  43 22   7.6   4.2
 29000 -40.1 -40.2  240  40 21   6.8   3.7 | -41.3 -42.3  235  42 22   7.4   4.1
 28000 -38.1 -36.6  245  39 20   6.8   3.8 | -39.1 -38.4  235  41 21   7.4   4.1
 27000 -36.0 -32.8  245  38 20   6.8   3.7 | -36.9 -34.4  235  40 21   7.4   4.0
 26000 -33.9 -29.0  245  38 19   7.1   3.9 | -34.6 -30.3  235  39 20   7.6   4.2
 25000 -31.8 -25.2  245  37 19   7.1   3.9 | -32.4 -26.3  240  38 20   7.7   4.2
 24000 -29.7 -21.5  250  36 19   7.1   3.9 | -30.1 -22.2  240  38 19   7.7   4.2
 23000 -27.4 -17.3  250  36 18   8.0   4.4 | -27.8 -18.0  245  37 19   7.7   4.2
 22000 -25.0 -13.0  250  36 18   8.0   4.4 | -25.5 -13.9  245  36 18   7.7   4.2
 21000 -22.6  -8.7  250  36 18   8.1   4.4 | -23.2  -9.8  245  35 18   7.7   4.3
 20000 -20.3  -4.5  250  35 18   8.0   4.4 | -20.9  -5.6  245  34 18   7.8   4.3
 19500 -19.1  -2.4  245  35 18   8.0   4.4 | -19.8  -3.6  245  34 17   7.8   4.3
 19000 -17.9  -0.2  245  35 18   8.0   4.4 | -18.6  -1.5  245  34 17   7.8   4.3
 18500 -16.7   1.9  245  35 18   8.1   4.4 | -17.5   0.5  245  34 17   7.8   4.3
 18000 -15.0   5.0  245  34 18   7.4   4.1 | -15.8   3.6  245  33 17   7.2   4.0
 17500 -14.0   6.8  245  34 17   7.5   4.1 | -14.8   5.4  245  33 17   7.3   4.0
 17000 -12.9   8.8  245  33 17   7.2   3.9 | -13.7   7.3  240  32 17   6.7   3.7
 16500 -11.8  10.8  240  33 17   7.1   3.9 | -12.8   9.0  240  31 16   6.5   3.6
 16000 -10.8  12.6  240  32 17   6.7   3.7 | -11.8  10.8  240  30 16   5.8   3.2
 15500  -9.9  14.2  235  31 16   6.0   3.3 | -11.2  11.8  235  29 15   4.1   2.3
 15000  -9.1  15.6  235  29 15   5.8   3.2 | -10.6  12.9  230  27 14   4.3   2.3
 14500  -8.5  16.7  230  28 14   2.7   1.5 | -10.4  13.3  225  24 13  -1.8  -1.0
 14000  -8.1  17.4  230  26 14   3.7   2.0 | -10.6  12.9  220  22 11  -0.5  -0.3
 13500  -8.1  17.4  225  24 12  -4.8  -2.6 | -11.3  11.7  215  19 10 -10.0  -5.5
 13000  -8.8  16.2  220  21 11  -3.9  -2.1 | -12.8   9.0  210  16  8  -9.7  -5.3
 12500  -9.8  14.4  215  18  9 -11.8  -6.5 | -14.4   6.1  200  13  7 -13.3  -7.3
 12000 -11.6  11.1  215  14  7 -12.3  -6.7 | -16.3   2.7  195  10  5 -14.1  -7.7
 11500 -13.4   7.9  210  10  5 -13.7  -7.5 | -18.0  -0.4  185   7  3  -7.6  -4.2
 11000 -15.5   4.1  205   7  3 -14.5  -7.9 | -19.0  -2.2  165   5  2  -8.0  -4.4
 10500 -17.0   1.4  195   4  2  -6.4  -3.5 | -19.5  -3.1  140   3  2   2.0   1.1
 10250 -17.5   0.5  180   3  1  -6.3  -3.5 | -19.4  -2.9  125   2  1   1.2   0.7
 10000 -18.0  -0.4  155   2  1  -6.9  -3.8 | -19.3  -2.7  085   2  1   1.1   0.6
  9750 -18.4  -1.1  120   1  1  -1.0  -0.5 | -19.2  -2.6  055   2  1   2.8   1.6
  9500 -18.1  -0.6  080   1  1   4.4   2.4 | -18.9  -2.0  045   2  1   5.3   2.9
  9250 -17.9  -0.2  045   2  1   3.7   2.0 | -18.5  -1.3  040   3  1   5.9   3.2
  9000 -17.6   0.3  030   3  1   3.3   1.8 | -18.0  -0.4  035   3  2   4.3   2.3
  8750 -17.3   0.9  030   3  2   4.1   2.2 | -17.8  -0.0  035   4  2   3.7   2.0
  8500 -16.9   1.6  030   4  2   6.8   3.7 | -17.4   0.7  035   5  2   6.3   3.5
  8250 -16.4   2.5  030   5  3   7.4   4.0 | -16.9   1.6  035   5  3   7.1   3.9
  8000 -15.9   3.4  030   6  3   5.5   3.0 | -16.4   2.5  035   6  3   6.9   3.8
  7750 -15.5   4.1  025   6  3   5.4   3.0 | -15.9   3.4  035   6  3   7.5   4.1
  7500 -15.0   5.0  025   7  3   7.6   4.1 | -15.3   4.5  035   7  3   8.8   4.9
  7250 -14.5   5.9  020   7  3   8.3   4.6 | -14.6   5.7  030   7  3   8.3   4.6
  7000 -13.8   7.2  020   7  3   8.3   4.5 | -14.1   6.6  025   7  3   6.8   3.7
  6750 -13.2   8.2  015   7  4   9.2   5.0 | -13.5   7.7  025   7  3   9.0   5.0
  6500 -12.5   9.5  015   7  3  10.1   5.5 | -12.8   9.0  020   6  3   9.9   5.4
  6250 -11.8  10.8  015   7  3   9.7   5.3 | -12.1  10.2  015   6  3   8.5   4.7
  6000 -11.1  12.0  010   6  3   9.1   5.0 | -11.5  11.3  015   6  3   8.3   4.6
  5750 -10.3  13.5  010   6  3  11.0   6.0 | -10.8  12.6  010   6  3   9.6   5.3
  5500  -9.3  15.3  010   6  3  16.9   9.3 | -10.0  14.0  005   5  2  13.3   7.3
________________________________________________________________________________

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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