Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 010050
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1749 MST Saturday, January 31, 2015

This forecast is for Sunday, February 1, 2015:

If the trigger temperature of 33.5 F/0.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9868 ft MSL (4581 ft AGL)

Forecast maximum temperature................... 35.0 F/2.1 C
Time of trigger temperature.................... 1245 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................. 8022 ft MSL (2734 ft AGL)
Thermal soaring outlook for Monday 02/02....... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Very strong northwest winds decr
Height of stable layer (12-18K ft MSL)......... 18079 ft MSL (12792 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 26689 ft MSL (21402 ft AGL)
Wave soaring outlook for Monday 02/02.......... Good

Remarks...

Sunrise/Sunset.................... 07:07:25 / 17:17:43 MST
Total possible sunshine........... 10 hr 10 min 18 sec (610 min 18 sec)
Altitude of sun at 12:12:56 MST... 33.26 degrees

Upper air data from numerical model forecast valid on 02/01/2015 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 9018 ft MSL (3731 ft AGL)
Lifted condensation level....... 9491 ft MSL (4203 ft AGL)
Lifted index.................... +14.5
K index......................... -0.9

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  -55.7 -68.3   275   42   22   2.7   1.5      M     M       M      M    M
 45000  -51.5 -60.7   290   53   27   2.8   1.6      M     M       M      M    M
 40000  -51.8 -61.2   300   65   34  -0.4  -0.2      M     M       M      M    M
 38000  -52.0 -61.6   305   71   37  -0.7  -0.4      M     M       M      M    M
 36000  -52.5 -62.5   310   77   40  -0.7  -0.4      M     M       M      M    M
 34000  -52.9 -63.2   320   85   44  -1.0  -0.5      M     M       M      M    M
 32000  -50.2 -58.4   325   95   49   5.8   3.2      M     M       M      M    M
 30000  -46.3 -51.3   335  107   55   6.5   3.6      M     M       M      M    M
 29000  -43.8 -46.8   335  110   57   8.7   4.8   30.7  87.3    21.9      M    M
 28000  -41.1 -42.0   335  113   58   8.7   4.8   30.3  86.5    21.9      M    M
 27000  -38.5 -37.3   335  115   59   8.6   4.7   29.9  85.9    21.9      M    M
 26000  -36.3 -33.3   335  114   59   6.0   3.3   29.2  84.5    21.5      M    M
 25000  -34.4 -29.9   335  109   56   6.1   3.4   27.7  81.9    20.7      M    M
 24000  -32.6 -26.7   335  104   53   6.1   3.4   26.4  79.5    19.9      M    M
 23000  -31.0 -23.8   330   98   50   3.0   1.6   24.8  76.6    18.8      M    M
 22000  -30.0 -22.0   330   89   46   3.3   1.8   22.4  72.2    17.0      M    M
 21000  -29.0 -20.2   325   81   42   3.3   1.8   20.1  68.1    15.3      M    M
 20000  -28.2 -18.8   325   75   39   2.1   1.2   17.6  63.6    13.4      M    M
 19500  -27.9 -18.2   325   73   37   2.1   1.2   16.2  61.1    12.3      M    M
 19000  -27.6 -17.7   325   70   36   2.1   1.2   14.8  58.7    11.2      M    M
 18500  -27.3 -17.1   325   68   35   2.1   1.2   13.5  56.3    10.2      M    M
 18000  -26.9 -16.4   325   66   34   2.8   1.5   12.2  54.0     9.1      M    M
 17500  -26.4 -15.5   325   64   33   3.7   2.0   11.2  52.1     8.2      M    M
 17000  -25.8 -14.4   325   61   32   3.7   2.0   10.1  50.2     7.4      M    M
 16500  -25.3 -13.5   325   59   30   3.8   2.1    9.1  48.4     6.5      M    M
 16000  -24.7 -12.5   325   55   28   3.7   2.1    8.1  46.6     5.6      M    M
 15500  -24.1 -11.4   325   52   27   5.4   2.9    7.2  44.9     4.9      M    M
 15000  -22.9  -9.2   325   46   24   5.6   3.1    6.1  43.0     3.9      M    M
 14500  -22.0  -7.6   320   42   21   6.3   3.5    5.5  41.9     3.3      M    M
 14000  -21.1  -6.0   320   38   19   6.2   3.4    4.9  40.8     2.8      M    M
 13500  -19.9  -3.8   320   34   18   9.6   5.3    4.6  40.3     2.5      M    M
 13000  -18.6  -1.5   320   31   16   9.4   5.1    4.5  40.2     2.4      M    M
 12500  -17.3   0.9   320   28   15   8.2   4.5    4.4  39.9     2.3      M    M
 12000  -16.0   3.2   320   26   13   8.3   4.6    4.2  39.5     2.0      M    M
 11500  -14.9   5.2   325   25   13   7.1   3.9    3.8  38.9     1.7      M    M
 11000  -13.8   7.2   325   24   13   7.1   3.9    3.4  38.2     1.3      M    M
 10500  -12.9   8.8   325   23   12   5.5   3.0    2.9  37.2     0.8      M    M
 10250  -12.5   9.5   325   22   11   6.4   3.5    2.6  36.6     0.5      M    M
 10000  -12.1  10.2   325   21   11   3.5   1.9    2.2  36.0     0.2      M    M
  9750  -11.9  10.6   325   20   11   3.8   2.1    1.7  35.0    -0.3    316  1.6
  9500  -11.4  11.5   330   20   10   7.0   3.8    1.4  34.5    -0.6    294  1.5
  9250  -11.0  12.2   330   19   10   6.3   3.4    1.1  34.0    -0.9    273  1.4
  9000  -10.5  13.1   330   18    9   5.3   2.9    0.8  33.5    -1.2    252  1.3
  8750  -10.2  13.6   335   17    9   3.5   1.9    0.4  32.7    -1.6    235  1.2
  8500  -10.0  14.0   340   16    8   3.3   1.8   -0.1  31.8    -2.1    221  1.1
  8250   -9.7  14.5   345   16    8   3.4   1.8   -0.6  30.9    -2.6    206  1.0
  8000   -9.5  14.9   355   15    8   2.8   1.6   -1.1  30.0    -3.1    191  1.0
  7750   -9.2  15.4   005   15    8   4.0   2.2   -1.6  29.1    -3.6    177  0.9
  7500   -8.9  16.0   010   15    8   5.4   3.0   -2.0  28.4    -3.9    159  0.8
  7250   -8.5  16.7   015   14    7   6.2   3.4   -2.3  27.9    -4.3    139  0.7
  7000   -8.0  17.6   015   12    6   7.0   3.9   -2.5  27.4    -4.5    117  0.6
  6750   -7.5  18.5   020   10    5   6.4   3.5   -2.8  27.0    -4.8     94  0.5
  6500   -7.0  19.4   025    9    4   8.1   4.4   -3.0  26.6    -5.0     72  0.4
  6250   -6.3  20.7   030    8    4   9.9   5.5   -3.0  26.6    -5.1     44  0.2
  6000   -5.6  21.9   030    6    3   9.4   5.2   -3.0  26.6    -5.1     16  0.1
  5750   -4.9  23.2   035    5    3  10.4   5.7   -3.0  26.6    -5.1      M    M
  5500   -4.0  24.8   040    5    3  12.8   7.0   -2.8  26.9    -5.0      M    M

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

           02/01/2015 at 0800 MST          |       02/01/2015 at 1100 MST
                                           |
K index... -15.0  LI... +6.8               | K index... -17.1  LI... +9.3
CAPE... 0.0  CIN... -0.8                   | CAPE... 0.0  CIN... M
                                           |
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 -55.9 -68.6  285  45 23   2.2   1.2 | -56.8 -70.2  290  41 21   2.6   1.4
 45000 -52.7 -62.9  290  54 28   2.1   1.2 | -52.9 -63.2  295  53 27   2.5   1.4
 40000 -52.7 -62.9  305  69 35  -0.3  -0.2 | -53.6 -64.5  310  67 35  -0.8  -0.4
 38000 -52.9 -63.2  310  75 39  -0.2  -0.1 | -53.9 -65.0  315  74 38   0.3   0.2
 36000 -53.0 -63.4  320  82 42  -0.2  -0.1 | -53.7 -64.7  325  81 42   0.3   0.2
 34000 -53.1 -63.6  325  90 46  -0.5  -0.3 | -53.5 -64.3  330  90 46  -0.2  -0.1
 32000 -50.5 -58.9  330  98 50   5.4   3.0 | -50.6 -59.1  335  94 48   5.7   3.2
 30000 -47.2 -53.0  335 107 55   5.1   2.8 | -47.1 -52.8  340  97 50   5.5   3.0
 29000 -45.0 -49.0  340 110 57   8.5   4.7 | -44.9 -48.8  340 100 52   7.8   4.3
 28000 -41.8 -43.2  340 113 58   8.5   4.7 | -42.0 -43.6  345 104 54   7.8   4.3
 27000 -39.2 -38.6  340 116 60   8.5   4.6 | -39.7 -39.5  345 108 56   7.8   4.3
 26000 -37.0 -34.6  340 115 59   6.5   3.6 | -37.4 -35.3  345 109 56   7.4   4.1
 25000 -35.0 -31.0  340 110 57   6.5   3.6 | -35.2 -31.4  345 107 55   7.4   4.1
 24000 -33.1 -27.6  335 106 54   6.5   3.6 | -33.0 -27.4  345 106 55   7.4   4.0
 23000 -31.3 -24.3  335 101 52   4.1   2.3 | -31.0 -23.8  340 103 53   5.6   3.1
 22000 -30.0 -22.0  335  95 49   4.3   2.4 | -29.3 -20.7  340  98 50   5.6   3.1
 21000 -28.8 -19.8  335  90 46   4.3   2.3 | -27.6 -17.7  340  93 48   5.7   3.1
 20000 -27.8 -18.0  335  84 43   2.0   1.1 | -26.4 -15.5  340  87 45   2.9   1.6
 19500 -27.6 -17.7  335  80 41   1.9   1.0 | -26.0 -14.8  340  84 43   2.8   1.5
 19000 -27.3 -17.1  335  76 39   1.9   1.0 | -25.6 -14.1  335  80 41   2.8   1.5
 18500 -27.0 -16.6  335  72 37   1.9   1.1 | -25.2 -13.4  335  77 40   2.8   1.5
 18000 -26.7 -16.1  335  69 35   2.3   1.3 | -24.7 -12.5  335  74 38   3.3   1.8
 17500 -26.3 -15.3  335  65 34   2.7   1.5 | -24.2 -11.6  335  72 37   3.6   2.0
 17000 -25.9 -14.6  335  62 32   2.9   1.6 | -23.6 -10.5  335  69 36   3.4   1.9
 16500 -25.3 -13.5  335  59 30   5.0   2.7 | -23.3  -9.9  335  66 34   2.1   1.2
 16000 -24.6 -12.3  330  56 29   4.6   2.5 | -22.9  -9.2  335  64 33   2.0   1.1
 15500 -23.7 -10.7  330  53 27   7.4   4.1 | -22.5  -8.5  335  61 31   3.6   2.0
 15000 -22.6  -8.7  330  50 26   7.5   4.1 | -22.0  -7.6  330  58 30   3.4   1.9
 14500 -21.2  -6.2  330  46 24   4.6   2.5 | -20.9  -5.6  330  53 27   6.3   3.5
 14000 -20.5  -4.9  330  44 22   4.8   2.6 | -20.0  -4.0  330  50 26   6.1   3.4
 13500 -19.7  -3.5  330  41 21   6.0   3.3 | -19.2  -2.6  330  47 24   4.7   2.6
 13000 -18.8  -1.8  330  38 19   5.9   3.3 | -18.5  -1.3  330  43 22   4.9   2.7
 12500 -17.9  -0.2  325  35 18   6.3   3.4 | -17.7   0.1  330  40 20   5.5   3.0
 12000 -17.0   1.4  325  33 17   6.3   3.4 | -17.0   1.4  325  36 18   5.5   3.0
 11500 -16.1   3.0  325  30 15   6.5   3.6 | -16.2   2.8  325  32 17   5.3   2.9
 11000 -15.2   4.6  325  26 13   6.6   3.6 | -15.4   4.3  325  28 15   5.5   3.0
 10500 -14.2   6.4  325  24 12   6.6   3.6 | -14.6   5.7  325  24 13   6.0   3.3
 10250 -13.7   7.3  325  23 12   7.6   4.2 | -14.1   6.6  325  23 12   7.0   3.9
 10000 -13.2   8.2  325  21 11   3.8   2.1 | -13.6   7.5  330  21 11   3.0   1.6
  9750 -13.0   8.6  325  21 11   4.2   2.3 | -13.5   7.7  330  20 10   4.3   2.4
  9500 -12.5   9.5  325  19 10   8.2   4.5 | -12.9   8.8  330  19 10   9.4   5.2
  9250 -11.9  10.6  325  18  9   7.2   3.9 | -12.3   9.9  330  17  9   7.8   4.3
  9000 -11.5  11.3  325  16  8   5.1   2.8 | -11.8  10.8  335  16  8   5.4   2.9
  8750 -11.2  11.8  320  14  7   4.1   2.3 | -11.5  11.3  335  14  7   5.2   2.8
  8500 -10.8  12.6  320  12  6   5.6   3.1 | -11.0  12.2  335  13  7   6.8   3.7
  8250 -10.4  13.3  320  11  5   4.7   2.6 | -10.5  13.1  335  12  6   6.6   3.6
  8000 -10.1  13.8  325   9  5   3.5   1.9 | -10.0  14.0  335  10  5   7.2   3.9
  7750  -9.9  14.2  335   7  4   4.3   2.4 |  -9.5  14.9  335   8  4   6.8   3.7
  7500  -9.5  14.9  350   6  3   5.6   3.1 |  -9.0  15.8  335   6  3   6.7   3.7
  7250  -9.0  15.8  360   5  3   6.0   3.3 |  -8.5  16.7  340   5  2   7.3   4.0
  7000  -8.6  16.5  015   4  2   6.4   3.5 |  -8.0  17.6  360   3  2   7.4   4.1
  6750  -8.1  17.4  035   3  2   5.9   3.2 |  -7.4  18.7  040   2  1   7.6   4.1
  6500  -7.7  18.1  060   3  2   8.2   4.5 |  -6.8  19.8  075   3  1   9.4   5.1
  6250  -6.9  19.6  065   3  2  10.4   5.7 |  -6.0  21.2  075   3  1  10.8   5.9
  6000  -6.2  20.8  075   3  2   9.7   5.3 |  -5.3  22.5  075   3  1   9.6   5.3
  5750  -5.5  22.1  080   4  2  10.2   5.6 |  -4.5  23.9  075   3  1  11.4   6.2
  5500  -4.7  23.5  075   4  2  11.4   6.2 |  -3.5  25.7  075   3  1  17.1   9.4

           02/01/2015 at 1400 MST          |       02/01/2015 at 1700 MST
                                           |
K index... -25.3  LI... +11.2              | K index... -26.3  LI... +12.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -57.3 -71.1  300  41 21   2.3   1.3 | -57.7 -71.9  295  40 21   2.0   1.1
 45000 -53.8 -64.8  295  45 23   2.2   1.2 | -54.7 -66.5  295  45 23   1.9   1.0
 40000 -55.8 -68.4  315  60 31  -1.7  -0.9 | -57.4 -71.3  315  64 33  -2.3  -1.2
 38000 -56.4 -69.5  325  69 36   0.8   0.4 | -58.3 -72.9  325  73 37   1.6   0.9
 36000 -55.8 -68.4  335  80 41   0.9   0.5 | -57.3 -71.1  335  78 40   1.5   0.8
 34000 -55.3 -67.5  340  93 48   1.0   0.5 | -56.4 -69.5  340  84 43   4.8   2.6
 32000 -51.5 -60.7  340  96 50   7.0   3.8 | -51.8 -61.2  340  81 42   7.6   4.2
 30000 -47.3 -53.1  345  99 51   7.1   3.9 | -47.2 -53.0  335  78 40   8.3   4.5
 29000 -45.1 -49.2  345  99 51   7.3   4.0 | -44.7 -48.5  335  79 41   8.4   4.6
 28000 -42.9 -45.2  345  98 50   7.3   4.0 | -42.1 -43.8  335  80 41   8.4   4.6
 27000 -40.2 -40.4  345  97 50   7.2   4.0 | -39.6 -39.3  340  81 42   8.5   4.6
 26000 -37.8 -36.0  345  97 50   8.6   4.7 | -37.3 -35.1  340  80 41   7.3   4.0
 25000 -35.2 -31.4  345  96 49   8.6   4.7 | -35.1 -31.2  340  78 40   7.3   4.0
 24000 -32.7 -26.9  345  95 49   8.6   4.7 | -32.9 -27.2  340  76 39   7.3   4.0
 23000 -30.3 -22.5  345  94 48   7.2   3.9 | -30.5 -22.9  340  74 38   8.8   4.8
 22000 -28.2 -18.8  345  91 47   7.2   3.9 | -27.8 -18.0  340  72 37   8.8   4.8
 21000 -26.0 -14.8  340  89 46   7.4   4.1 | -25.2 -13.4  340  70 36   9.2   5.0
 20000 -24.4 -11.9  340  85 44   4.7   2.6 | -23.1  -9.6  340  68 35   6.2   3.4
 19500 -23.7 -10.7  340  82 42   4.7   2.6 | -22.2  -8.0  340  68 35   6.2   3.4
 19000 -23.0  -9.4  340  80 41   4.8   2.6 | -21.3  -6.3  340  67 35   6.2   3.4
 18500 -22.3  -8.1  340  77 40   4.9   2.7 | -20.3  -4.5  340  67 34   6.3   3.4
 18000 -21.6  -6.9  340  75 39   3.1   1.7 | -19.4  -2.9  340  66 34   5.5   3.0
 17500 -21.2  -6.2  340  72 37   2.9   1.6 | -18.6  -1.5  340  64 33   5.5   3.0
 17000 -20.8  -5.4  340  70 36   3.2   1.7 | -17.4   0.7  340  61 31   3.6   2.0
 16500 -20.2  -4.4  340  68 35   3.8   2.1 | -16.9   1.6  340  59 30   3.7   2.0
 16000 -19.7  -3.5  340  66 34   3.9   2.1 | -16.3   2.7  340  57 29   3.4   1.9
 15500 -19.2  -2.6  340  63 33   2.1   1.1 | -15.8   3.6  340  55 29   3.3   1.8
 15000 -18.9  -2.0  335  61 31   2.3   1.3 | -15.3   4.5  340  54 28   2.9   1.6
 14500 -18.6  -1.5  335  58 30   0.9   0.5 | -15.0   5.0  340  52 27   2.2   1.2
 14000 -18.5  -1.3  335  53 27   1.4   0.8 | -14.6   5.7  340  50 26   2.0   1.1
 13500 -18.1  -0.6  330  48 25   3.5   1.9 | -14.5   5.9  335  47 24   0.8   0.4
 13000 -17.6   0.3  325  43 22   3.6   2.0 | -14.3   6.3  335  44 23   1.0   0.6
 12500 -17.0   1.4  325  38 20   4.4   2.4 | -14.1   6.6  330  39 20   2.3   1.2
 12000 -16.4   2.5  325  33 17   4.8   2.6 | -13.8   7.2  330  34 18   2.6   1.4
 11500 -15.5   4.1  325  29 15   6.9   3.8 | -13.3   8.1  325  29 15   4.3   2.4
 11000 -14.5   5.9  325  25 13   6.8   3.7 | -12.7   9.1  320  24 13   4.7   2.6
 10500 -13.5   7.7  325  23 12   6.5   3.6 | -11.9  10.6  320  21 11   6.3   3.5
 10250 -13.0   8.6  325  21 11   7.5   4.1 | -11.4  11.5  320  20 10   7.0   3.8
 10000 -12.5   9.5  330  20 10   3.8   2.1 | -10.9  12.4  320  18  9   4.1   2.3
  9750 -12.4   9.7  330  19 10   4.7   2.6 | -10.7  12.7  320  18  9   5.2   2.9
  9500 -11.8  10.8  330  18  9   9.1   5.0 | -10.1  13.8  320  16  8   8.9   4.9
  9250 -11.2  11.8  330  16  8   7.6   4.2 |  -9.5  14.9  320  15  8   7.8   4.3
  9000 -10.6  12.9  335  14  7   6.1   3.3 |  -8.9  16.0  320  14  7   6.5   3.6
  8750 -10.2  13.6  335  13  7   6.1   3.3 |  -8.5  16.7  320  12  6   5.8   3.2
  8500  -9.7  14.5  335  11  6   7.3   4.0 |  -8.1  17.4  325  11  6   6.4   3.5
  8250  -9.2  15.4  340   9  5   6.7   3.6 |  -7.6  18.3  325   9  5   6.2   3.4
  8000  -8.7  16.3  345   7  4   6.3   3.5 |  -7.1  19.2  325   8  4   6.6   3.6
  7750  -8.3  17.1  350   6  3   6.3   3.5 |  -6.6  20.1  330   6  3   5.7   3.1
  7500  -7.8  18.0  350   5  2   7.2   3.9 |  -6.3  20.7  330   4  2   5.0   2.7
  7250  -7.2  19.0  355   4  2   9.0   4.9 |  -5.9  21.4  325   3  1   5.7   3.1
  7000  -6.5  20.3  355   4  2   9.9   5.4 |  -5.4  22.3  295   1  1   6.4   3.5
  6750  -5.8  21.6  355   3  2   9.0   5.0 |  -5.0  23.0  220   1  1   5.0   2.8
  6500  -5.1  22.8  355   3  2   9.8   5.4 |  -4.6  23.7  195   2  1   7.7   4.2
  6250  -4.3  24.3  350   3  2  11.1   6.1 |  -3.9  25.0  195   2  1  10.9   6.0
  6000  -3.5  25.7  350   3  2  10.2   5.6 |  -3.1  26.4  195   3  1  10.2   5.6
  5750  -2.8  27.0  350   3  1  11.5   6.3 |  -2.3  27.9  195   3  1   9.2   5.0
  5500  -1.8  28.8  350   3  1  15.9   8.7 |  -1.8  28.8  195   3  1   6.6   3.6
________________________________________________________________________________

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.

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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