Soaring Guidance
Issued by NWS Denver/Boulder, CO

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124
UXUS97 KBOU 100131
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1829 MST Thursday, January 9, 2025

This forecast is for Friday, January 10, 2025:

If the trigger temperature of 33.3 F/0.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 654 ft/min (3.3 m/s)
   Maximum height of thermals.................. 13195 ft MSL (7894 ft AGL)

Forecast maximum temperature................... 39.0 F/4.3 C
Time of trigger temperature.................... 1130 MST
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................. 9634 ft MSL (4333 ft AGL)
Thermal soaring outlook for Saturday 01/11..... Fair

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 17863 ft MSL (12562 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 29932 ft MSL (24631 ft AGL)
Wave soaring outlook for Saturday 01/11........ Fair

Remarks...

Sunrise/Sunset.................... 07:20:10 / 16:54:15 MST
Total possible sunshine........... 9 hr 34 min 5 sec (574 min 5 sec)
Altitude of sun at 12:07:13 MST... 28.38 degrees

Upper air data from numerical model forecast valid on 01/10/2025 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 24036 ft MSL (18735 ft AGL)
Lifted condensation level....... 15986 ft MSL (10684 ft AGL)
Lifted index.................... +17.7
K index......................... -31.3

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -54.5 -66.1   345   38   20   2.3   1.2      M     M       M      M    M
 45000  -51.1 -60.0   005   48   25   2.0   1.1      M     M       M      M    M
 40000  -49.4 -56.9   005   63   33   1.1   0.6      M     M       M      M    M
 38000  -49.2 -56.6   005   70   36  -0.9  -0.5      M     M       M      M    M
 36000  -49.8 -57.6   015   80   41  -1.0  -0.5      M     M       M      M    M
 34000  -50.3 -58.5   020   91   47  -1.6  -0.9      M     M       M      M    M
 32000  -48.0 -54.4   025  107   55   4.0   2.2      M     M       M      M    M
 30000  -45.6 -50.1   025  121   62   6.0   3.3   32.2  90.0    21.1      M    M
 29000  -43.3 -45.9   025  117   60   7.5   4.1   31.2  88.1    20.6      M    M
 28000  -41.0 -41.8   025  113   58   7.5   4.1   30.3  86.5    20.2      M    M
 27000  -38.8 -37.8   020  109   56   7.5   4.1   29.5  85.1    19.8      M    M
 26000  -36.4 -33.5   020  105   54   8.2   4.5   28.8  83.9    19.5      M    M
 25000  -33.9 -29.0   020  102   53   8.3   4.5   28.2  82.7    19.3      M    M
 24000  -31.4 -24.5   020  100   51   8.2   4.5   27.7  81.8    19.1      M    M
 23000  -29.1 -20.4   015   97   50   7.4   4.1   27.0  80.7    18.8      M    M
 22000  -26.8 -16.2   015   95   49   7.4   4.1   26.1  79.0    18.3      M    M
 21000  -24.6 -12.3   015   93   48   7.6   4.2   25.4  77.6    17.9      M    M
 20000  -23.5 -10.3   015   87   45   1.4   0.8   23.2  73.8    16.3      M    M
 19500  -23.3  -9.9   015   84   43   1.3   0.7   21.7  71.0    15.1      M    M
 19000  -23.1  -9.6   010   80   41   1.3   0.7   20.2  68.3    13.9      M    M
 18500  -22.9  -9.2   010   76   39   1.1   0.6   18.7  65.7    12.7      M    M
 18000  -22.7  -8.9   010   72   37  -2.6  -1.4   17.3  63.1    11.5      M    M
 17500  -23.6 -10.5   005   66   34  -5.6  -3.1   14.5  58.2     9.2      M    M
 17000  -24.8 -12.6   005   58   30  -1.8  -1.0   10.7  51.2     5.9      M    M
 16500  -24.8 -12.6   360   53   27  -0.1  -0.1    9.0  48.1     4.4      M    M
 16000  -24.9 -12.8   360   48   25   1.8   1.0    7.3  45.2     3.0      M    M
 15500  -24.2 -11.6   355   45   23   4.8   2.6    6.4  43.5     2.2      M    M
 15000  -23.5 -10.3   355   43   22   5.2   2.9    5.6  42.0     1.5      M    M
 14500  -22.5  -8.5   355   40   21   7.1   3.9    5.0  41.0     1.0      M    M
 14000  -21.5  -6.7   350   38   20   7.0   3.8    4.5  40.2     0.6      M    M
 13500  -20.4  -4.7   350   36   19   7.4   4.1    4.1  39.4     0.2      M    M
 13000  -19.3  -2.7   350   34   18   7.4   4.0    3.7  38.7    -0.2    629  3.2
 12500  -18.2  -0.8   350   33   17   7.5   4.1    3.3  38.0    -0.5    581  3.0
 12000  -17.0   1.4   350   31   16   7.4   4.1    3.0  37.4    -0.9    533  2.7
 11500  -16.0   3.2   350   29   15   7.2   3.9    2.6  36.6    -1.3    485  2.5
 11000  -14.9   5.2   350   26   13   7.2   4.0    2.2  35.9    -1.6    438  2.2
 10500  -13.8   7.2   345   23   12   7.1   3.9    1.8  35.2    -2.0    390  2.0
 10250  -13.2   8.2   345   21   11   8.5   4.6    1.6  34.9    -2.2    366  1.9
 10000  -12.7   9.1   345   20   10   3.5   1.9    1.4  34.6    -2.4    342  1.7
  9750  -12.5   9.5   345   19   10   5.0   2.8    0.8  33.4    -3.0    331  1.7
  9500  -11.8  10.8   345   18    9  11.2   6.2    0.8  33.4    -3.0    301  1.5
  9250  -11.1  12.0   340   16    8   9.1   5.0    0.8  33.5    -3.0    272  1.4
  9000  -10.5  13.1   340   15    8   6.0   3.3    0.7  33.2    -3.1    247  1.3
  8750  -10.1  13.8   340   14    7   6.3   3.4    0.3  32.6    -3.5    228  1.2
  8500   -9.4  15.1   335   13    7  10.2   5.6    0.2  32.4    -3.6    201  1.0
  8250   -8.7  16.3   330   12    6   7.4   4.1    0.2  32.4    -3.6    173  0.9
  8000   -8.4  16.9   325   10    5   4.1   2.2   -0.1  31.7    -4.0    154  0.8
  7750   -8.0  17.6   320    9    4   6.0   3.3   -0.5  31.0    -4.4    136  0.7
  7500   -7.5  18.5   305    7    4   7.5   4.1   -0.7  30.7    -4.6    113  0.6
  7250   -7.0  19.4   295    7    3   6.1   3.3   -1.0  30.3    -4.9     90  0.5
  7000   -6.6  20.1   280    7    4   5.1   2.8   -1.3  29.7    -5.2     71  0.4
  6750   -6.2  20.8   270    7    4   6.2   3.4   -1.6  29.1    -5.5     51  0.3
  6500   -5.8  21.6   260    8    4   1.3   0.7   -2.0  28.4    -5.9     33  0.2
  6250   -6.0  21.2   260   10    5  -3.9  -2.2   -2.9  26.8    -6.9     32  0.2
  6000   -6.2  20.8   260   11    6  -0.6  -0.3   -3.8  25.1    -7.8     30  0.2
  5750   -6.4  20.5   260   12    6  -8.8  -4.8   -4.8  23.4    -8.8     29  0.1
  5500   -7.8  18.0   245    8    4 -26.9 -14.8   -6.9  19.6   -11.0     64  0.3

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

           01/10/2025 at 0800 MST          |       01/10/2025 at 1100 MST
                                           |
CAPE...     0.0    LI...      +15.7        | CAPE...     0.0    LI...      +14.3
CINH...    -0.2    K Index... -32.6        | CINH...    -0.1    K Index... -22.6
                                           |
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 -56.1 -69.0  345  39 20   2.5   1.4 | -57.2 -71.0  335  30 15   2.3   1.3
 45000 -52.4 -62.3  350  51 26   1.9   1.0 | -53.7 -64.7  345  37 19   1.3   0.7
 40000 -51.4 -60.5  010  70 36   0.7   0.4 | -55.2 -67.4  005  70 36  -1.0  -0.5
 38000 -51.2 -60.2  015  79 41  -0.4  -0.2 | -54.8 -66.6  005  83 43   2.4   1.3
 36000 -51.4 -60.5  015  89 46  -0.4  -0.2 | -53.3 -63.9  005  96 49   2.4   1.3
 34000 -51.4 -60.5  015  99 51   5.0   2.7 | -51.6 -60.9  010 107 55   7.0   3.8
 32000 -47.9 -54.2  020 105 54   5.9   3.2 | -47.4 -53.3  010 101 52   7.0   3.9
 30000 -44.3 -47.7  025 111 57   7.5   4.1 | -43.2 -45.8  015  96 49   7.8   4.3
 29000 -42.0 -43.6  025 107 55   7.6   4.2 | -40.9 -41.6  015  92 47   7.7   4.2
 28000 -39.7 -39.5  025 103 53   7.6   4.2 | -38.0 -36.4  015  88 45   7.7   4.2
 27000 -37.4 -35.3  025  99 51   7.6   4.2 | -35.7 -32.3  020  84 43   7.7   4.2
 26000 -35.1 -31.2  020  95 49   7.5   4.1 | -33.4 -28.1  020  81 42   7.5   4.1
 25000 -32.9 -27.2  020  92 47   7.5   4.1 | -31.2 -24.2  020  78 40   7.5   4.1
 24000 -30.6 -23.1  015  89 46   7.6   4.1 | -28.9 -20.0  020  75 38   7.6   4.2
 23000 -28.3 -18.9  015  87 45   7.7   4.2 | -26.8 -16.2  015  73 38   7.2   3.9
 22000 -26.0 -14.8  015  86 45   7.8   4.3 | -24.6 -12.3  015  72 37   7.2   3.9
 21000 -23.7 -10.7  015  86 44   8.0   4.4 | -22.5  -8.5  010  71 36   6.9   3.8
 20000 -21.8  -7.2  015  83 43   5.6   3.0 | -20.7  -5.3  010  69 35   6.0   3.3
 19500 -21.0  -5.8  015  82 42   5.6   3.1 | -19.8  -3.6  010  67 35   6.1   3.3
 19000 -20.2  -4.4  015  81 42   5.6   3.1 | -18.9  -2.0  010  66 34   6.1   3.3
 18500 -19.3  -2.7  015  79 41   5.8   3.2 | -18.0  -0.4  010  65 34   6.1   3.3
 18000 -18.6  -1.5  015  77 40   2.3   1.2 | -17.2   1.0  010  64 33   4.6   2.5
 17500 -18.4  -1.1  010  74 38   1.6   0.9 | -16.5   2.3  010  62 32   4.8   2.6
 17000 -18.2  -0.8  010  69 36  -1.2  -0.6 | -15.8   3.6  010  60 31   3.7   2.1
 16500 -18.4  -1.1  005  65 34  -1.3  -0.7 | -15.3   4.5  010  58 30   3.3   1.8
 16000 -18.6  -1.5  005  61 32  -0.7  -0.4 | -14.8   5.4  010  56 29   2.7   1.5
 15500 -18.6  -1.5  360  58 30  -0.2  -0.1 | -14.6   5.7  005  54 28   0.9   0.5
 15000 -18.6  -1.5  360  54 28   0.3   0.2 | -14.4   6.1  005  52 27   1.0   0.6
 14500 -18.4  -1.1  355  50 26   1.6   0.9 | -14.2   6.4  360  49 25   0.9   0.5
 14000 -18.2  -0.8  355  46 24   1.8   1.0 | -14.1   6.6  355  47 24   1.3   0.7
 13500 -17.7   0.1  350  42 22   3.6   2.0 | -13.8   7.2  355  44 23   2.0   1.1
 13000 -17.2   1.0  350  39 20   3.8   2.1 | -13.5   7.7  350  41 21   2.5   1.4
 12500 -16.4   2.5  345  36 18   6.5   3.6 | -12.9   8.8  350  38 20   3.9   2.1
 12000 -15.4   4.3  345  33 17   6.5   3.6 | -12.4   9.7  345  35 18   4.5   2.4
 11500 -14.4   6.1  345  31 16   7.4   4.1 | -11.5  11.3  345  32 17   6.2   3.4
 11000 -13.3   8.1  345  30 15   7.4   4.0 | -10.6  12.9  345  30 15   6.5   3.6
 10500 -12.2  10.0  345  28 14   7.1   3.9 |  -9.5  14.9  345  28 14   7.2   3.9
 10250 -11.6  11.1  350  27 14   8.6   4.7 |  -9.0  15.8  345  26 14   8.0   4.4
 10000 -11.1  12.0  350  26 13   3.0   1.7 |  -8.5  16.7  345  26 13   3.7   2.0
  9750 -11.0  12.2  350  26 13   4.3   2.3 |  -8.3  17.1  345  25 13   4.8   2.6
  9500 -10.3  13.5  350  24 12  10.9   6.0 |  -7.6  18.3  345  24 12   9.9   5.4
  9250  -9.6  14.7  350  22 11   8.6   4.7 |  -7.0  19.4  345  22 11   7.9   4.3
  9000  -9.0  15.8  345  20 10   4.7   2.6 |  -6.5  20.3  340  20 10   4.5   2.5
  8750  -8.8  16.2  345  19 10   4.7   2.6 |  -6.2  20.8  340  19 10   4.8   2.6
  8500  -8.2  17.2  345  16  8   8.4   4.6 |  -5.7  21.7  335  16  8   7.4   4.1
  8250  -7.7  18.1  340  13  7   6.6   3.6 |  -5.2  22.6  330  14  7   5.5   3.0
  8000  -7.3  18.9  330  11  6   4.3   2.3 |  -4.9  23.2  320  12  6   3.3   1.8
  7750  -6.9  19.6  325   9  5   6.8   3.7 |  -4.6  23.7  310  10  5   5.7   3.1
  7500  -6.3  20.7  305   8  4   8.6   4.7 |  -4.1  24.6  300   9  5   7.6   4.2
  7250  -5.7  21.7  295   8  4   5.6   3.1 |  -3.6  25.5  285   9  5   5.9   3.2
  7000  -5.4  22.3  285   8  4   3.8   2.1 |  -3.2  26.2  280   9  4   4.5   2.5
  6750  -5.1  22.8  280   8  4   5.7   3.1 |  -2.8  27.0  275   8  4   7.3   4.0
  6500  -4.8  23.4  275   9  5  -0.2  -0.1 |  -2.3  27.9  270   9  4   4.8   2.6
  6250  -5.1  22.8  270  10  5  -6.6  -3.6 |  -2.2  28.0  265   8  4   0.8   0.4
  6000  -5.5  22.1  260  10  5  -3.0  -1.7 |  -2.1  28.2  255   7  4   1.1   0.6
  5750  -5.9  21.4  255  11  6 -10.9  -6.0 |  -2.0  28.4  250   7  4   4.2   2.3
  5500  -7.5  18.5  245   8  4 -29.6 -16.3 |  -1.4  29.5  240   6  3  14.2   7.8

           01/10/2025 at 1400 MST          |       01/10/2025 at 1700 MST
                                           |
CAPE...     0.0    LI...      +11.1        | CAPE...     0.0    LI...       +6.5
CINH...     0.0    K Index... -11.3        | CINH...    -0.4    K Index...  +6.8
                                           |
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 -57.6 -71.7  325  26 14   2.7   1.5 | -57.7 -71.9  305  28 14   2.2   1.2
 45000 -53.6 -64.5  350  31 16   1.2   0.7 | -54.4 -65.9  330  27 14   0.6   0.3
 40000 -56.0 -68.8  360  60 31  -1.6  -0.9 | -57.1 -70.8  345  52 27  -1.7  -1.0
 38000 -55.6 -68.1  360  70 36   3.1   1.7 | -56.1 -69.0  350  61 31   4.3   2.3
 36000 -53.7 -64.7  360  80 41   3.1   1.7 | -53.6 -64.5  350  68 35   4.3   2.3
 34000 -51.5 -60.7  360  87 45   7.5   4.1 | -50.7 -59.3  350  73 38   7.7   4.2
 32000 -47.2 -53.0  360  80 41   7.1   3.9 | -46.2 -51.2  350  66 34   7.5   4.1
 30000 -42.9 -45.2  360  74 38   8.5   4.7 | -41.7 -43.1  350  59 30   7.6   4.2
 29000 -40.4 -40.7  360  72 37   8.4   4.6 | -39.4 -38.9  350  58 30   7.7   4.2
 28000 -37.9 -36.2  360  70 36   8.4   4.6 | -37.1 -34.8  345  57 29   7.7   4.2
 27000 -35.4 -31.7  005  68 35   8.4   4.6 | -34.3 -29.7  345  56 29   7.7   4.2
 26000 -32.3 -26.1  005  65 33   8.1   4.4 | -32.0 -25.6  345  53 27   7.7   4.2
 25000 -29.9 -21.8  005  62 32   8.1   4.4 | -29.7 -21.5  345  50 26   7.8   4.3
 24000 -27.5 -17.5  010  58 30   8.0   4.4 | -27.4 -17.3  345  47 24   7.8   4.3
 23000 -25.3 -13.5  010  57 29   7.1   3.9 | -25.0 -13.0  345  45 23   8.0   4.4
 22000 -23.2  -9.8  005  56 29   7.1   3.9 | -22.6  -8.7  345  43 22   8.0   4.4
 21000 -21.1  -6.0  005  55 28   6.9   3.8 | -20.2  -4.4  345  42 21   7.4   4.1
 20000 -19.2  -2.6  005  55 28   6.6   3.6 | -18.2  -0.8  345  42 22   6.9   3.8
 19500 -18.2  -0.8  005  55 28   6.6   3.6 | -17.2   1.0  345  43 22   6.9   3.8
 19000 -17.2   1.0  005  55 28   6.6   3.6 | -16.2   2.8  345  43 22   6.8   3.8
 18500 -16.2   2.8  005  54 28   6.5   3.5 | -15.2   4.6  345  44 22   6.5   3.6
 18000 -15.4   4.3  005  53 27   4.8   2.7 | -14.4   6.1  345  43 22   4.5   2.5
 17500 -14.7   5.5  005  51 26   4.9   2.7 | -13.7   7.3  345  43 22   4.6   2.5
 17000 -14.0   6.8  005  50 26   5.4   3.0 | -13.1   8.4  350  43 22   4.7   2.6
 16500 -13.1   8.4  005  48 25   5.5   3.0 | -12.4   9.7  350  43 22   4.8   2.6
 16000 -12.3   9.9  005  47 24   5.4   3.0 | -11.7  10.9  350  43 22   5.2   2.9
 15500 -11.5  11.3  360  47 24   5.2   2.8 | -10.8  12.6  350  43 22   5.9   3.2
 15000 -10.7  12.7  360  46 24   5.2   2.9 |  -9.9  14.2  350  42 21   5.9   3.2
 14500 -10.1  13.8  355  45 23   3.4   1.8 |  -9.2  15.4  350  41 21   4.3   2.3
 14000  -9.6  14.7  355  45 23   3.6   2.0 |  -8.6  16.5  350  40 20   4.3   2.4
 13500  -9.1  15.6  350  44 23   2.6   1.4 |  -7.9  17.8  350  39 20   5.6   3.1
 13000  -8.7  16.3  350  43 22   2.6   1.4 |  -7.0  19.4  350  38 19   5.5   3.0
 12500  -8.2  17.2  350  41 21   3.3   1.8 |  -5.6  21.9  345  36 18   7.3   4.0
 12000  -7.4  18.7  345  37 19   3.5   1.9 |  -4.5  23.9  345  34 18   6.9   3.8
 11500  -6.9  19.6  345  34 17   3.8   2.1 |  -3.6  25.5  345  32 17   5.3   2.9
 11000  -6.3  20.7  340  30 16   4.1   2.3 |  -2.7  27.1  345  30 15   5.0   2.7
 10500  -5.6  21.9  335  27 14   5.1   2.8 |  -2.1  28.2  340  27 14   3.4   1.9
 10250  -5.2  22.6  335  25 13   5.8   3.2 |  -1.9  28.6  340  26 13   2.4   1.3
 10000  -4.8  23.4  335  23 12   2.9   1.6 |  -1.6  29.1  335  24 13   6.7   3.7
  9750  -4.6  23.7  335  23 12   4.0   2.2 |  -0.9  30.4  335  22 11   8.3   4.5
  9500  -4.1  24.6  330  21 11   7.6   4.2 |  -0.5  31.1  330  20 10   4.7   2.6
  9250  -3.6  25.5  325  19 10   7.1   3.9 |  -0.1  31.8  330  19 10   6.5   3.6
  9000  -3.1  26.4  325  17  9   3.3   1.8 |   0.4  32.7  325  17  9   2.8   1.6
  8750  -3.0  26.6  320  16  8   2.7   1.5 |   0.5  32.9  320  15  8   2.0   1.1
  8500  -2.6  27.3  315  14  7   5.9   3.3 |   0.8  33.4  315  14  7   4.8   2.7
  8250  -2.2  28.0  305  13  7   4.7   2.6 |   1.1  34.0  305  12  6   4.1   2.2
  8000  -1.9  28.6  300  12  6   2.9   1.6 |   1.4  34.5  295  11  6   3.7   2.1
  7750  -1.7  28.9  290  12  6   4.8   2.6 |   1.7  35.1  295  11  6   4.1   2.3
  7500  -1.2  29.8  285  11  6   7.9   4.3 |   2.0  35.6  290  11  6   5.5   3.0
  7250  -0.7  30.7  275  11  5   5.0   2.8 |   2.4  36.3  290  11  6   3.2   1.7
  7000  -0.4  31.3  275  11  6   3.1   1.7 |   2.5  36.5  285  12  6   0.4   0.2
  6750  -0.2  31.6  275  11  6   3.8   2.1 |   2.5  36.5  280  14  7  -0.4  -0.2
  6500   0.1  32.2  265  10  5   3.8   2.1 |   2.5  36.5  275  14  7  -0.9  -0.5
  6250   0.3  32.5  260   9  5   4.0   2.2 |   2.4  36.3  270  13  7  -0.7  -0.4
  6000   0.6  33.1  255   8  4   3.3   1.8 |   2.4  36.3  265  12  6   1.0   0.5
  5750   0.8  33.4  245   7  4   5.9   3.2 |   2.3  36.1  255  10  5  -4.6  -2.5
  5500   1.4  34.5  235   5  3  11.6   6.3 |   1.3  34.3  240   7  4 -21.2 -11.6
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

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