Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 251328
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0628 MST Tuesday, November 25, 2014

This forecast is for Tuesday, November 25, 2014:

If the trigger temperature of 39.7 F/4.3 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 235 ft/min (1.2 m/s)
   Maximum height of thermals.................. 13755 ft MSL (8470 ft AGL)

Forecast maximum temperature................... 51.0 F/11.0 C
Time of trigger temperature.................... 0945 MST
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................. 11626 ft MSL (6340 ft AGL)
Thermal soaring outlook for Wednesday 11/26.... Poor

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 13648 ft MSL (8363 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 18813 ft MSL (13528 ft AGL)
Wave soaring outlook for Wednesday 11/26....... Good

Remarks...

Sunrise/Sunset.................... 06:55:19 / 16:37:40 MST
Total possible sunshine........... 9 hr 42 min 21 sec (582 min 21 sec)
Altitude of sun at 11:46:39 MST... 29.45 degrees

Upper air data from rawinsonde observation taken on 11/25/2014 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 18438 ft MSL (13153 ft AGL)
Lifted condensation level....... 16798 ft MSL (11512 ft AGL)
Lifted index.................... +5.0
K index......................... +0.4

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  -55.9 -68.6   325   60   31   3.5   1.9  111.1 231.9    56.9      M    M
 45000  -58.0 -72.4   320   64   33 -12.8  -7.0   81.2 178.2    42.9      M    M
 40000  -53.1 -63.6   335   75   38 -22.2 -12.2   65.8 150.4    35.9      M    M
 38000  -58.6 -73.5   350   92   48   4.7   2.6   48.4 119.1    25.3      M    M
 36000  -56.1 -69.0   350  120   62   3.4   1.8   43.4 110.2    22.5      M    M
 34000  -59.0 -74.2   345  143   74   0.3   0.2   31.0  87.8    14.4      M    M
 32000  -54.5 -66.1   350  139   71   8.5   4.7   29.0  84.3    13.4      M    M
 30000  -50.5 -58.9   350  120   62   6.2   3.4   25.5  77.9    11.1      M    M
 29000  -48.1 -54.6   350  114   58   8.7   4.8   24.8  76.6    10.7      M    M
 28000  -45.5 -49.9   345  107   55   8.8   4.8   24.3  75.8    10.5      M    M
 27000  -42.8 -45.0   345  101   52   8.8   4.8   24.0  75.2    10.4      M    M
 26000  -40.2 -40.4   340   95   49   8.7   4.8   23.8  74.8    10.3      M    M
 25000  -38.2 -36.8   345   87   45   3.7   2.1   22.6  72.6     9.5      M    M
 24000  -37.1 -34.8   340   70   36   3.9   2.1   20.3  68.6     7.8      M    M
 23000  -35.6 -32.1   340   59   30   6.6   3.6   18.5  65.4     6.5      M    M
 22000  -33.2 -27.8   335   58   30   8.3   4.5   17.8  64.1     6.0      M    M
 21000  -30.7 -23.3   335   57   29   8.3   4.5   17.3  63.2     5.6      M    M
 20000  -28.3 -18.9   330   56   29   8.3   4.5   16.9  62.4     5.3      M    M
 19500  -27.0 -16.6   330   56   29   8.0   4.4   16.6  61.9     5.1      M    M
 19000  -25.9 -14.6   325   57   29   7.5   4.1   16.2  61.2     4.8      M    M
 18500  -24.8 -12.6   325   58   30   7.6   4.2   15.9  60.6     4.5      M    M
 18000  -23.7 -10.7   325   57   29   6.8   3.8   15.5  59.8     4.1      M    M
 17500  -22.7  -8.9   325   54   28   6.9   3.8   14.9  58.9     3.7      M    M
 17000  -21.6  -6.9   325   51   26   6.9   3.8   14.4  58.0     3.3      M    M
 16500  -20.6  -5.1   330   48   25   6.9   3.8   14.0  57.1     2.9      M    M
 16000  -19.6  -3.3   330   45   23   6.9   3.8   13.5  56.3     2.5      M    M
 15500  -18.6  -1.5   330   42   22   6.9   3.8   13.0  55.4     2.0      M    M
 15000  -17.0   1.4   330   39   20   6.9   3.8   12.2  54.0     1.4      M    M
 14500  -16.0   3.2   330   37   19   7.2   3.9   11.7  53.1     0.9      M    M
 14000  -15.2   4.6   330   34   17   3.0   1.6   11.1  51.9     0.3      M    M
 13500  -14.8   5.4   325   29   15   2.4   1.3    9.9  49.7    -0.8    617  3.1
 13000  -14.4   6.1   325   24   13   5.4   3.0    8.8  47.8    -1.8    588  3.0
 12500  -13.3   8.1   315   20   10   6.7   3.7    8.3  46.9    -2.3    543  2.8
 12000  -12.3   9.9   310   17    9   6.7   3.7    7.8  46.1    -2.7    498  2.5
 11500  -11.3  11.7   315   25   13   5.1   2.8    7.3  45.2    -3.2    453  2.3
 11000  -10.9  12.4   315   32   16   3.2   1.8    6.3  43.3    -4.2    424  2.2
 10500  -10.4  13.3   310   31   16   4.3   2.3    5.2  41.4    -5.2    396  2.0
 10250   -9.9  14.2   305   31   16   8.2   4.5    4.9  40.9    -5.5    374  1.9
 10000   -9.3  15.3   305   31   16   8.6   4.7    4.9  40.8    -5.6    347  1.8
  9750   -8.7  16.3   305   31   16   7.6   4.2    4.7  40.5    -5.7    322  1.6
  9500   -8.1  17.4   300   31   16   7.9   4.3    4.6  40.3    -5.9    297  1.5
  9250   -7.5  18.5   300   31   16   7.8   4.3    4.4  40.0    -6.0    272  1.4
  9000   -6.9  19.6   300   31   16   7.8   4.3    4.3  39.8    -6.2    247  1.3
  8750   -6.3  20.7   300   28   14   7.8   4.3    4.2  39.5    -6.4    222  1.1
  8500   -5.7  21.7   300   25   13   7.8   4.3    4.0  39.2    -6.5    197  1.0
  8250   -5.2  22.6   295   22   11   7.8   4.3    3.9  38.9    -6.7    172  0.9
  8000   -4.6  23.7   295   19   10   7.8   4.3    3.7  38.7    -6.8    147  0.7
  7750   -4.0  24.8   290   17    9   7.8   4.3    3.6  38.4    -7.0    122  0.6
  7500   -3.4  25.9   285   15    8   7.8   4.3    3.4  38.1    -7.2     97  0.5
  7250   -2.8  27.0   280   14    7   7.8   4.3    3.2  37.8    -7.3     72  0.4
  7000   -2.2  28.0   275   12    6   7.7   4.2    3.1  37.6    -7.5     47  0.2
  6750   -1.6  29.1   255   11    5   8.3   4.5    2.9  37.3    -7.7     22  0.1
  6500   -1.1  30.0   235   10    5   5.0   2.8    2.8  37.0    -7.9      M    M
  6250   -0.9  30.4   215   11    6   1.2   0.7    2.2  36.0    -8.4      M    M
  6000   -0.7  30.7   200   14    7   4.6   2.5    1.7  35.0    -9.0      M    M
  5750   -0.6  30.9   200   10    5  -5.1  -2.8    1.1  34.0    -9.6      M    M
  5500   -2.0  28.4   200    5    2 -32.1 -17.6   -1.0  30.2   -11.8      M    M

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

           11/25/2014 at 0800 MST          |       11/25/2014 at 1100 MST
                                           |
K index... +5.5  LI... +5.3                | K index... +12.1  LI... +3.6
CAPE... 0.0  CIN... -0.5                   | CAPE... 0.0  CIN... -0.5
                                           |
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 -56.2 -69.2  335  33 17  -0.5  -0.3 | -57.7 -71.9  335  28 14  -0.4  -0.2
 45000 -57.0 -70.6  345  41 21  -0.5  -0.2 | -58.2 -72.8  325  47 24  -0.3  -0.2
 40000 -57.5 -71.5  350  76 39  -0.3  -0.2 | -58.1 -72.6  345  87 45   0.1   0.1
 38000 -57.7 -71.9  350  91 47  -0.2  -0.1 | -58.1 -72.6  345 100 51  -0.2  -0.1
 36000 -57.8 -72.0  350 105 54  -0.2  -0.1 | -58.2 -72.8  345 103 53  -0.2  -0.1
 34000 -57.9 -72.2  350 120 62  -1.2  -0.7 | -58.3 -72.9  345 107 55   4.1   2.2
 32000 -53.2 -63.8  350 117 60   7.8   4.3 | -52.9 -63.2  345 104 53   9.1   5.0
 30000 -48.5 -55.3  350 112 58   7.9   4.3 | -47.5 -53.5  345 101 52   8.9   4.9
 29000 -46.1 -51.0  350 106 55   7.8   4.3 | -44.9 -48.8  345 102 53   8.6   4.7
 28000 -43.8 -46.8  350 100 52   7.8   4.3 | -41.7 -43.1  350 105 54   8.6   4.7
 27000 -41.5 -42.7  350  94 49   7.8   4.3 | -39.1 -38.4  350 107 55   8.5   4.7
 26000 -39.1 -38.4  350  88 45   7.7   4.2 | -36.7 -34.1  350 103 53   7.8   4.3
 25000 -36.8 -34.2  345  81 42   7.7   4.2 | -34.4 -29.9  350  97 50   7.8   4.3
 24000 -34.5 -30.1  340  75 38   7.7   4.2 | -32.1 -25.8  345  92 47   7.9   4.3
 23000 -32.2 -26.0  340  68 35   7.7   4.2 | -29.9 -21.8  345  84 43   7.1   3.9
 22000 -29.9 -21.8  335  62 32   7.7   4.2 | -27.8 -18.0  340  74 38   7.1   3.9
 21000 -27.6 -17.7  330  56 29   7.7   4.2 | -25.7 -14.3  335  65 33   7.1   3.9
 20000 -25.6 -14.1  330  50 26   6.4   3.5 | -23.6 -10.5  330  63 32   7.2   4.0
 19500 -24.7 -12.5  325  47 24   6.4   3.5 | -22.5  -8.5  330  62 32   7.2   4.0
 19000 -23.7 -10.7  325  45 23   6.4   3.5 | -21.4  -6.5  330  61 31   7.2   4.0
 18500 -22.7  -8.9  325  42 22   6.3   3.5 | -20.3  -4.5  330  60 31   7.1   3.9
 18000 -21.7  -7.1  325  42 22   8.3   4.6 | -19.4  -2.9  330  60 31   6.0   3.3
 17500 -20.5  -4.9  330  46 24   8.1   4.5 | -18.5  -1.3  330  60 31   6.1   3.3
 17000 -19.3  -2.7  330  49 25   6.7   3.7 | -17.6   0.3  330  61 31   6.3   3.4
 16500 -18.4  -1.1  330  47 24   6.0   3.3 | -16.7   1.9  335  60 31   6.3   3.5
 16000 -17.0   1.4  330  45 23   7.1   3.9 | -15.7   3.7  335  59 30   6.4   3.5
 15500 -15.9   3.4  330  46 24   7.3   4.0 | -14.8   5.4  335  58 30   6.6   3.6
 15000 -14.9   5.2  335  48 25   7.0   3.8 | -13.8   7.2  335  57 29   6.7   3.7
 14500 -13.8   7.2  330  48 25   6.8   3.8 | -12.8   9.0  335  57 29   7.2   4.0
 14000 -12.8   9.0  330  48 25   6.5   3.6 | -11.2  11.8  335  56 29   7.8   4.3
 13500 -11.9  10.6  330  49 25   6.1   3.3 |  -9.9  14.2  340  57 29   8.3   4.6
 13000 -11.0  12.2  330  49 25   5.8   3.2 |  -8.7  16.3  340  57 29   8.2   4.5
 12500 -10.2  13.6  325  50 26   5.3   2.9 |  -7.5  18.5  335  57 29   7.7   4.2
 12000  -9.4  15.1  325  50 26   5.0   2.7 |  -6.3  20.7  335  58 30   7.5   4.1
 11500  -8.7  16.3  320  50 26   4.1   2.3 |  -5.3  22.5  335  57 29   6.9   3.8
 11000  -8.1  17.4  320  49 25   3.6   2.0 |  -4.2  24.4  330  57 29   5.6   3.1
 10500  -7.7  18.1  315  48 25   2.7   1.5 |  -3.7  25.3  325  56 29   2.9   1.6
 10250  -7.5  18.5  310  47 24   2.9   1.6 |  -3.5  25.7  325  56 29   3.6   2.0
 10000  -7.3  18.9  310  47 24   1.8   1.0 |  -3.3  26.1  320  55 29   1.0   0.5
  9750  -7.2  19.0  310  46 24   2.2   1.2 |  -3.3  26.1  320  54 28  -0.6  -0.3
  9500  -6.9  19.6  305  44 23   3.6   2.0 |  -3.3  26.1  315  53 27   0.9   0.5
  9250  -6.7  19.9  305  42 22   3.1   1.7 |  -3.2  26.2  310  51 26   0.5   0.3
  9000  -6.5  20.3  300  41 21   2.4   1.3 |  -3.2  26.2  310  50 26   0.8   0.5
  8750  -6.3  20.7  300  38 20   3.9   2.1 |  -3.1  26.4  305  46 24   1.3   0.7
  8500  -5.9  21.4  295  35 18   5.2   2.9 |  -3.0  26.6  305  43 22   1.1   0.6
  8250  -5.5  22.1  295  32 17   5.3   2.9 |  -2.9  26.8  300  40 20   2.4   1.3
  8000  -5.1  22.8  290  29 15   5.6   3.1 |  -2.6  27.3  300  36 18   4.9   2.7
  7750  -4.7  23.5  290  26 13   6.4   3.5 |  -2.2  28.0  295  31 16   5.1   2.8
  7500  -4.1  24.6  290  23 12   7.4   4.1 |  -1.8  28.8  295  28 15   4.7   2.6
  7250  -3.6  25.5  285  21 11   7.5   4.1 |  -1.5  29.3  290  25 13   6.3   3.4
  7000  -3.0  26.6  280  19 10   7.9   4.3 |  -0.9  30.4  290  22 11   7.8   4.3
  6750  -2.4  27.7  280  16  8   7.4   4.0 |  -0.4  31.3  285  19 10   6.2   3.4
  6500  -1.9  28.6  275  14  7   5.0   2.7 |   0.1  32.2  280  16  8   7.2   4.0
  6250  -1.7  28.9  265  13  6   3.2   1.8 |   0.8  33.4  275  14  7   9.8   5.4
  6000  -1.4  29.5  255  11  6   5.1   2.8 |   1.5  34.7  270  12  6   9.5   5.2
  5750  -1.0  30.2  240  10  5   1.5   0.8 |   2.2  36.0  270  11  6  10.3   5.6
  5500  -1.4  29.5  230   8  4 -11.9  -6.5 |   3.1  37.6  265  10  5  13.6   7.4

           11/25/2014 at 1400 MST          |       11/25/2014 at 1700 MST
                                           |
K index... +13.6  LI... +3.0               | K index... +14.7  LI... +2.9
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -1.4
                                           |
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 -58.0 -72.4  330  27 14   1.3   0.7 | -59.0 -74.2  310  39 20   0.6   0.3
 45000 -56.1 -69.0  335  49 25   1.7   0.9 | -58.1 -72.6  315  59 31   0.8   0.4
 40000 -58.8 -73.8  335  92 48  -2.0  -1.1 | -59.7 -75.5  335 103 53  -1.1  -0.6
 38000 -58.9 -74.0  340 103 53   2.9   1.6 | -59.4 -74.9  340 115 59   3.3   1.8
 36000 -57.2 -71.0  340 100 52   2.9   1.6 | -57.4 -71.3  340 115 59   3.3   1.8
 34000 -55.4 -67.7  340  98 50   5.3   2.9 | -55.4 -67.7  345 114 59   6.3   3.4
 32000 -51.2 -60.2  340  94 48   7.0   3.9 | -50.7 -59.3  340 106 54   7.9   4.3
 30000 -46.3 -51.3  340  89 46   8.9   4.9 | -45.4 -49.7  335  97 50   7.8   4.3
 29000 -43.7 -46.7  335  87 45   8.8   4.8 | -43.0 -45.4  335  93 48   7.8   4.3
 28000 -41.0 -41.8  335  85 44   8.8   4.8 | -40.7 -41.3  340  89 46   7.8   4.3
 27000 -38.4 -37.1  335  83 43   8.7   4.7 | -38.3 -36.9  340  86 44   7.9   4.3
 26000 -36.0 -32.8  335  84 43   8.1   4.4 | -35.9 -32.6  335  83 42   8.0   4.4
 25000 -33.6 -28.5  335  87 45   8.1   4.4 | -33.6 -28.5  335  79 41   8.0   4.4
 24000 -31.2 -24.2  335  89 46   8.2   4.5 | -31.2 -24.2  330  76 39   8.1   4.4
 23000 -29.0 -20.2  340  89 46   7.0   3.8 | -28.9 -20.0  330  73 38   7.3   4.0
 22000 -26.9 -16.4  340  88 45   7.0   3.9 | -26.8 -16.2  330  70 36   7.3   4.0
 21000 -24.8 -12.6  340  86 44   7.1   3.9 | -24.6 -12.3  330  67 34   7.4   4.1
 20000 -22.7  -8.9  335  73 38   7.1   3.9 | -22.4  -8.3  330  65 33   7.5   4.1
 19500 -21.7  -7.1  335  66 34   7.2   3.9 | -21.3  -6.3  330  64 33   7.5   4.1
 19000 -20.6  -5.1  330  60 31   7.2   3.9 | -20.1  -4.2  325  63 33   7.5   4.1
 18500 -19.5  -3.1  325  53 27   7.1   3.9 | -19.0  -2.2  325  63 32   7.6   4.1
 18000 -18.5  -1.3  325  54 28   7.0   3.8 | -17.9  -0.2  325  63 32   7.5   4.1
 17500 -17.5   0.5  325  58 30   7.1   3.9 | -16.8   1.8  325  63 32   7.6   4.1
 17000 -16.5   2.3  330  61 31   6.4   3.5 | -15.7   3.7  325  63 32   7.3   4.0
 16500 -15.5   4.1  330  61 31   6.3   3.4 | -14.6   5.7  325  62 32   7.3   4.0
 16000 -14.6   5.7  330  62 32   6.5   3.6 | -13.5   7.7  325  62 32   7.0   3.8
 15500 -13.6   7.5  330  62 32   6.7   3.7 | -12.0  10.4  325  63 33   6.7   3.6
 15000 -12.2  10.0  330  61 32   6.5   3.6 | -11.0  12.2  330  64 33   7.0   3.8
 14500 -11.2  11.8  330  60 31   6.4   3.5 | -10.0  14.0  325  62 32   7.1   3.9
 14000 -10.3  13.5  335  58 30   7.2   4.0 |  -8.9  16.0  325  61 31   7.3   4.0
 13500  -9.1  15.6  335  57 29   7.9   4.3 |  -7.8  18.0  325  61 31   7.4   4.0
 13000  -7.9  17.8  335  55 28   7.8   4.3 |  -6.7  19.9  325  61 32   7.0   3.8
 12500  -6.8  19.8  335  54 28   7.5   4.1 |  -5.8  21.6  325  62 32   6.3   3.4
 12000  -5.6  21.9  335  53 27   7.6   4.2 |  -4.9  23.2  320  62 32   6.1   3.4
 11500  -4.5  23.9  330  52 27   7.8   4.3 |  -4.0  24.8  320  59 30   5.8   3.2
 11000  -3.3  26.1  330  51 26   6.6   3.6 |  -3.1  26.4  320  56 29   5.3   2.9
 10500  -2.6  27.3  325  50 26   4.1   2.3 |  -2.5  27.5  315  55 28   4.3   2.3
 10250  -2.3  27.9  325  50 26   4.6   2.5 |  -2.1  28.2  315  54 28   4.6   2.5
 10000  -1.9  28.6  325  50 26   4.9   2.7 |  -1.8  28.8  315  53 28   4.6   2.5
  9750  -1.6  29.1  320  49 25   3.3   1.8 |  -1.5  29.3  315  51 26   3.7   2.0
  9500  -1.4  29.5  315  48 25   2.3   1.3 |  -1.2  29.8  310  49 25   3.3   1.8
  9250  -1.2  29.8  315  47 24   2.3   1.2 |  -1.0  30.2  310  47 24   3.4   1.9
  9000  -1.1  30.0  310  46 24   0.3   0.2 |  -0.7  30.7  310  45 23   3.4   1.9
  8750  -1.1  30.0  310  43 22   1.1   0.6 |  -0.5  31.1  305  43 22   3.4   1.9
  8500  -1.0  30.2  305  41 21   2.4   1.3 |  -0.2  31.6  305  40 20   3.2   1.7
  8250  -0.8  30.6  305  38 20   2.8   1.6 |   0.0  32.0  305  37 19   4.0   2.2
  8000  -0.5  31.1  300  34 18   4.9   2.7 |   0.4  32.7  305  33 17   5.7   3.1
  7750  -0.1  31.8  300  30 15   6.4   3.5 |   0.8  33.4  305  30 15   5.6   3.1
  7500   0.4  32.7  300  27 14   6.7   3.7 |   1.2  34.2  305  27 14   4.7   2.6
  7250   1.0  33.8  300  24 13   8.4   4.6 |   1.6  34.9  305  25 13   6.6   3.6
  7000   1.7  35.1  300  22 12  10.2   5.6 |   2.2  36.0  305  22 11   8.3   4.6
  6750   2.4  36.3  300  20 11   8.9   4.9 |   2.8  37.0  305  19 10   7.4   4.0
  6500   3.1  37.6  300  19 10   9.1   5.0 |   3.3  37.9  305  17  9   7.3   4.0
  6250   3.8  38.8  300  18  9  10.4   5.7 |   3.9  39.0  305  14  7   7.6   4.2
  6000   4.6  40.3  300  16  8  10.6   5.8 |   4.5  40.1  305  12  6   8.0   4.4
  5750   5.3  41.5  300  15  8   9.8   5.4 |   5.0  41.0  305  10  5   6.4   3.5
  5500   6.1  43.0  300  13  7  10.1   5.5 |   5.3  41.5  305   7  4   1.8   1.0
________________________________________________________________________________

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.

CIN (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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