Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 021404
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0704 MST Monday, March 2, 2015

This forecast is for Monday, March 2, 2015:

If the trigger temperature of 54.4 F/12.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 21 ft/min (0.1 m/s)
   Maximum height of thermals.................. 7989 ft MSL (2704 ft AGL)

Forecast maximum temperature................... 36.0 F/2.7 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................. 7780 ft MSL (2494 ft AGL)
Thermal soaring outlook for Tuesday 03/03...... Poor

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 37484 ft MSL (32199 ft AGL)
Wave soaring outlook for Tuesday 03/03......... Poor

Remarks...

Sunrise/Sunset.................... 06:31:16 / 17:51:16 MST
Total possible sunshine........... 11 hr 20 min 1 sec (680 min 1 sec)
Altitude of sun at 12:11:31 MST... 43.15 degrees

Upper air data from rawinsonde observation taken on 03/02/2015 at 0500 MST

Freezing level.................. 8556 ft MSL (3271 ft AGL)
Additional freezing level....... 9456 ft MSL (4171 ft AGL)
Convective condensation level... 7004 ft MSL (1719 ft AGL)
Lifted condensation level....... 9515 ft MSL (4230 ft AGL)
Lifted index.................... +15.8
K index......................... +14.6

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  -63.3 -81.9   260   86   44  -0.6  -0.3   94.9 202.9    52.9      M    M
 45000  -59.7 -75.5   245  103   53  -2.9  -1.6   76.4 169.5    45.3      M    M
 40000  -61.7 -79.1   240  115   59   1.1   0.6   49.1 120.5    30.8      M    M
 38000  -58.6 -73.5   245  122   63   6.0   3.3   45.0 113.0    28.9      M    M
 36000  -55.4 -67.7   245  118   61   6.8   3.7   40.9 105.7    26.8      M    M
 34000  -51.1 -60.0   245  109   56   9.3   5.1   38.9 102.0    26.1      M    M
 32000  -45.5 -49.9   245  108   56   9.2   5.1   38.4 101.1    26.4      M    M
 30000  -40.7 -41.3   245  105   54   7.8   4.3   37.1  98.8    26.1      M    M
 29000  -38.0 -36.4   245  101   52   7.4   4.1   35.9  96.6    25.6      M    M
 28000  -35.8 -32.4   245   98   51   7.5   4.1   35.0  95.0    25.2      M    M
 27000  -34.3 -29.7   245   95   49   4.4   2.4   33.2  91.8    24.1      M    M
 26000  -32.5 -26.5   245   93   48   7.0   3.9   31.8  89.2    23.3      M    M
 25000  -30.9 -23.6   245   90   46   2.7   1.5   30.1  86.1    22.2      M    M
 24000  -29.1 -20.4   250   85   44   6.2   3.4   28.7  83.7    21.4      M    M
 23000  -27.2 -17.0   250   78   40   7.1   3.9   27.5  81.4    20.6      M    M
 22000  -24.9 -12.8   250   71   37   8.1   4.5   26.7  80.1    20.2      M    M
 21000  -22.5  -8.5   250   65   33   8.1   4.5   26.1  79.0    19.9      M    M
 20000  -20.2  -4.4   250   58   30   6.6   3.6   25.4  77.7    19.5      M    M
 19500  -19.2  -2.6   250   54   28   6.7   3.7   24.9  76.7    19.2      M    M
 19000  -18.2  -0.8   255   50   26   6.6   3.6   24.3  75.8    18.8      M    M
 18500  -17.2   1.0   250   49   25   5.8   3.2   23.8  74.8    18.4      M    M
 18000  -16.3   2.7   250   49   25   6.9   3.8   23.1  73.6    18.0      M    M
 17500  -15.3   4.5   250   48   25   6.7   3.7   22.6  72.6    17.6      M    M
 17000  -14.4   6.1   250   48   25   6.7   3.7   22.0  71.7    17.2      M    M
 16500  -13.4   7.9   250   47   24   7.0   3.9   21.6  70.8    16.8      M    M
 16000  -12.1  10.2   250   47   24   9.1   5.0   21.3  70.4    16.7      M    M
 15500  -10.8  12.6   250   46   24   8.0   4.4   21.2  70.2    16.7      M    M
 15000  -10.0  14.0   250   46   24   4.2   2.3   20.5  68.8    16.1      M    M
 14500   -8.9  16.0   250   45   23   7.6   4.2   19.3  66.8    15.1      M    M
 14000   -7.7  18.1   250   43   22   8.1   4.4   19.0  66.3    15.0      M    M
 13500   -6.6  20.1   250   41   21   8.1   4.4   18.7  65.7    14.8      M    M
 13000   -5.4  22.3   250   39   20   8.1   4.5   18.5  65.2    14.6      M    M
 12500   -4.2  24.4   245   37   19   8.4   4.6   18.2  64.8    14.4      M    M
 12000   -3.1  26.4   245   35   18   5.6   3.1   17.8  64.1    14.1      M    M
 11500   -2.3  27.9   240   35   18   5.8   3.2   17.1  62.9    13.5      M    M
 11000   -1.5  29.3   240   34   18   5.8   3.2   16.5  61.7    12.9      M    M
 10500   -0.6  30.9   235   34   18   6.3   3.5   15.9  60.6    12.4      M    M
 10250   -0.2  31.6   235   34   18   3.9   2.2   15.6  60.1    12.1      M    M
 10000   -0.1  31.8   230   33   17   0.7   0.4   15.0  59.0    11.6      M    M
  9750   -0.1  31.8   230   30   15   0.8   0.5   14.3  57.7    10.9      M    M
  9500   -0.0  32.0   230   27   14   0.9   0.5   13.6  56.4    10.2      M    M
  9250    0.1  32.2   225   24   13   0.7   0.4   12.9  55.2     9.6      M    M
  9000    0.1  32.2   225   22   11   1.3   0.7   12.2  53.9     8.9      M    M
  8750    0.2  32.4   225   21   11  -0.9  -0.5   11.5  52.7     8.3      M    M
  8500   -0.1  31.8   225   20   11  -4.2  -2.3   10.5  50.9     7.4      M    M
  8250   -1.4  29.5   220   20   10 -44.8 -24.6    8.4  47.1     5.3      M    M
  8000   -6.0  21.2   220   19   10 -60.1 -33.0    2.7  36.9     0.0      M    M
  7750   -8.8  16.2   220   15    8 -20.4 -11.2   -1.0  30.2    -3.5    497  2.5
  7500   -9.5  14.9   220   12    6  -4.6  -2.5   -2.5  27.4    -5.0    512  2.6
  7250   -9.6  14.7   220    9    4   3.1   1.7   -3.4  25.8    -5.9    508  2.6
  7000   -9.1  15.6   225    5    3   7.9   4.3   -3.6  25.5    -6.1    485  2.5
  6750   -8.6  16.5   235    4    2   6.6   3.6   -3.9  25.1    -6.3    462  2.3
  6500   -8.1  17.4   245    4    2   7.0   3.8   -4.1  24.7    -6.6    439  2.2
  6250   -7.6  18.3   260    4    2   6.9   3.8   -4.3  24.3    -6.8    417  2.1
  6000   -7.1  19.2   275    4    2   6.9   3.8   -4.5  23.9    -7.0    394  2.0
  5750   -6.6  20.1   250    3    2   7.0   3.9   -4.7  23.5    -7.3    371  1.9
  5500   -6.1  21.0   215    3    2   1.8   1.0   -5.1  22.9    -7.6    352  1.8

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

           03/02/2015 at 0800 MST          |       03/02/2015 at 1100 MST
                                           |
K index... +17.0  LI... +275.1             | K index... +8.7  LI... +275.2
CAPE... 0.0  CIN... 0.0                    | 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 -61.5 -78.7  250  66 34   1.7   1.0 | -61.4 -78.5  250  67 35   1.1   0.6
 45000 -58.9 -74.0  250 101 52   1.3   0.7 | -59.7 -75.5  250 103 53   0.9   0.5
 40000 -59.5 -75.1  245 110 57  -0.4  -0.2 | -59.2 -74.6  240 111 57   0.3   0.2
 38000 -58.2 -72.8  245 111 57   5.1   2.8 | -57.7 -71.9  240 112 57   5.1   2.8
 36000 -54.8 -66.6  245 108 56   5.1   2.8 | -54.3 -65.7  240 108 56   5.1   2.8
 34000 -51.2 -60.2  240 105 54   8.7   4.8 | -50.7 -59.3  240 105 54   8.2   4.5
 32000 -46.0 -50.8  240 103 53   8.7   4.8 | -45.8 -50.4  235  99 51   8.2   4.5
 30000 -40.9 -41.6  240 100 52   7.4   4.1 | -40.8 -41.4  235  94 48   8.4   4.6
 29000 -38.7 -37.7  240  98 50   7.5   4.1 | -38.3 -36.9  235  93 48   8.5   4.6
 28000 -36.4 -33.5  245  95 49   7.5   4.1 | -35.7 -32.3  235  93 48   8.5   4.6
 27000 -34.2 -29.6  245  93 48   7.1   3.9 | -33.2 -27.8  240  92 47   8.1   4.4
 26000 -32.4 -26.3  245  88 46   5.9   3.2 | -31.0 -23.8  240  90 46   7.2   3.9
 25000 -30.6 -23.1  245  84 43   5.9   3.2 | -28.9 -20.0  240  87 45   7.2   3.9
 24000 -28.9 -20.0  245  79 41   5.8   3.2 | -26.7 -16.1  240  85 44   7.4   4.0
 23000 -26.8 -16.2  245  72 37   7.1   3.9 | -24.9 -12.8  240  80 41   5.7   3.1
 22000 -24.7 -12.5  250  64 33   7.0   3.9 | -23.2  -9.8  240  75 39   5.8   3.2
 21000 -22.6  -8.7  250  56 29   7.3   4.0 | -21.5  -6.7  245  70 36   5.6   3.1
 20000 -20.2  -4.4  250  56 29   8.0   4.4 | -19.9  -3.8  245  66 34   5.1   2.8
 19500 -19.0  -2.2  250  57 29   8.0   4.4 | -19.2  -2.6  245  65 33   5.1   2.8
 19000 -17.8  -0.0  250  57 29   8.0   4.4 | -18.4  -1.1  245  63 32   5.1   2.8
 18500 -16.1   3.0  255  57 29   6.4   3.5 | -17.2   1.0  250  60 31   6.3   3.5
 18000 -15.2   4.6  255  55 28   5.7   3.1 | -16.2   2.8  250  57 30   7.0   3.9
 17500 -14.4   6.1  255  52 27   5.7   3.1 | -15.1   4.8  250  55 28   7.1   3.9
 17000 -13.6   7.5  255  50 26   6.1   3.3 | -14.0   6.8  245  52 27   7.6   4.2
 16500 -12.7   9.1  250  48 25   6.1   3.3 | -12.9   8.8  245  48 25   7.5   4.1
 16000 -11.8  10.8  250  45 23   6.8   3.8 | -11.7  10.9  245  45 23   8.5   4.6
 15500 -10.7  12.7  250  43 22   6.9   3.8 | -10.4  13.3  245  42 22   8.6   4.7
 15000  -9.7  14.5  250  41 21   7.0   3.9 |  -9.2  15.4  240  39 20   8.3   4.5
 14500  -8.7  16.3  245  41 21   7.1   3.9 |  -8.0  17.6  245  44 23   8.0   4.4
 14000  -7.7  18.1  245  41 21   7.7   4.2 |  -6.8  19.8  245  49 25   7.8   4.3
 13500  -6.4  20.5  245  42 22   9.0   4.9 |  -5.7  21.7  245  51 26   7.2   4.0
 13000  -5.0  23.0  245  44 23   8.8   4.8 |  -4.6  23.7  250  52 27   7.2   4.0
 12500  -3.9  25.0  245  43 22   7.4   4.1 |  -3.6  25.5  250  52 27   7.0   3.9
 12000  -2.8  27.0  245  40 21   7.6   4.2 |  -2.5  27.5  245  51 26   7.1   3.9
 11500  -1.6  29.1  245  39 20   8.5   4.6 |  -1.5  29.3  245  49 25   6.9   3.8
 11000  -0.4  31.3  240  38 19   8.1   4.4 |  -0.5  31.1  245  47 24   6.9   3.8
 10500   0.4  32.7  240  36 18   4.1   2.3 |   0.5  32.9  240  44 23   6.9   3.8
 10250   0.7  33.3  240  34 18   4.1   2.3 |   1.0  33.8  240  43 22   6.5   3.6
 10000   1.1  34.0  235  33 17   5.3   2.9 |   1.5  34.7  240  41 21   8.2   4.5
  9750   1.4  34.5  235  31 16   3.6   2.0 |   2.1  35.8  240  40 21   7.9   4.4
  9500   1.6  34.9  235  30 16   0.8   0.4 |   2.6  36.7  240  39 20   5.8   3.2
  9250   1.7  35.1  235  29 15   2.4   1.3 |   3.0  37.4  235  37 19   7.2   3.9
  9000   1.8  35.2  230  27 14  -1.3  -0.7 |   3.5  38.3  235  36 18   3.9   2.1
  8750   1.5  34.7  230  26 13  -5.6  -3.1 |   3.5  38.3  235  34 17   0.2   0.1
  8500   1.1  34.0  230  23 12  -5.7  -3.1 |   3.5  38.3  235  31 16  -0.1  -0.1
  8250   0.7  33.3  230  21 11  -4.9  -2.7 |   3.5  38.3  235  29 15   1.8   1.0
  8000   0.2  32.4  230  19 10  -9.9  -5.4 |   3.5  38.3  230  26 14  -5.6  -3.1
  7750  -0.8  30.6  230  15  8 -15.0  -8.2 |   2.7  36.9  230  22 11 -13.6  -7.5
  7500  -1.8  28.8  230  13  6 -13.9  -7.6 |   1.8  35.2  230  18  9 -11.7  -6.4
  7250  -2.9  26.8  230  10  5 -15.6  -8.6 |   0.9  33.6  230  15  7 -13.2  -7.3
  7000  -4.1  24.6  230   7  4 -18.9 -10.4 |  -0.3  31.5  225  11  6 -19.1 -10.5
  6750  -5.5  22.1  230   4  2 -18.7 -10.3 |  -1.8  28.8  220   8  4 -20.9 -11.4
  6500  -6.8  19.8  240   2  1 -15.9  -8.7 |  -3.3  26.1  215   5  3 -21.6 -11.8
  6250  -7.7  18.1  330   1  0  -6.4  -3.5 |  -4.7  23.5  185   2  1 -12.3  -6.8
  6000  -7.8  18.0  355   1  1  -0.0  -0.0 |  -5.1  22.8  155   1  0  -4.3  -2.3
  5750  -7.9  17.8  005   2  1  -2.7  -1.5 |  -5.5  22.1  050   1  1  -2.8  -1.5
  5500  -8.1  17.4  030   2  1  -2.0  -1.1 |  -5.1  22.8  025   2  1  15.7   8.6

           03/02/2015 at 1400 MST          |       03/02/2015 at 1700 MST
                                           |
K index... +6.7  LI... +275.7              | K index... +9.0  LI... +275.3
CAPE... 0.0  CIN... -0.5                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -61.1 -78.0  250  66 34   1.7   1.0 | -62.1 -79.8  245  77 40   1.9   1.0
 45000 -58.5 -73.3  245 101 52   1.6   0.9 | -59.2 -74.6  240  99 51   1.8   1.0
 40000 -57.2 -71.0  245 118 61   0.8   0.4 | -58.2 -72.8  235 126 65   0.6   0.3
 38000 -55.6 -68.1  240 123 64   4.3   2.3 | -56.1 -69.0  235 133 68   6.1   3.4
 36000 -53.0 -63.4  240 129 67   4.3   2.4 | -52.4 -62.3  235 135 70   6.1   3.4
 34000 -50.2 -58.4  240 132 68   7.4   4.1 | -48.6 -55.5  230 137 71   8.4   4.6
 32000 -45.9 -50.6  240 118 61   7.2   3.9 | -43.7 -46.7  235 135 70   8.2   4.5
 30000 -41.5 -42.7  235 106 55   8.3   4.6 | -38.9 -38.0  235 133 68   6.3   3.5
 29000 -38.4 -37.1  235 104 53   8.2   4.5 | -36.6 -33.9  235 126 65   6.2   3.4
 28000 -36.0 -32.8  235 102 52   8.2   4.5 | -34.7 -30.5  235 121 62   6.2   3.4
 27000 -33.5 -28.3  235  99 51   7.9   4.4 | -32.9 -27.2  235 115 59   6.4   3.5
 26000 -31.2 -24.2  235  97 50   7.6   4.1 | -30.9 -23.6  235 110 57   6.7   3.7
 25000 -29.0 -20.2  235  94 49   7.6   4.2 | -28.8 -19.8  235 106 54   6.7   3.7
 24000 -26.7 -16.1  235  92 47   7.6   4.2 | -26.8 -16.2  235 101 52   6.8   3.7
 23000 -24.7 -12.5  235  88 45   6.4   3.5 | -24.9 -12.8  235  96 50   6.2   3.4
 22000 -22.8  -9.0  235  84 43   6.4   3.5 | -23.1  -9.6  235  92 47   6.2   3.4
 21000 -20.9  -5.6  235  80 41   6.2   3.4 | -21.2  -6.2  235  88 45   6.1   3.4
 20000 -19.2  -2.6  235  74 38   5.5   3.0 | -19.5  -3.1  240  80 41   5.6   3.1
 19500 -18.4  -1.1  235  71 37   5.5   3.0 | -18.7  -1.7  240  76 39   5.6   3.1
 19000 -17.6   0.3  235  69 35   5.5   3.0 | -17.9  -0.2  240  72 37   5.7   3.1
 18500 -16.8   1.8  235  66 34   5.5   3.0 | -17.1   1.2  245  68 35   5.6   3.1
 18000 -15.9   3.4  235  63 33   6.6   3.6 | -16.1   3.0  245  65 33   7.5   4.1
 17500 -14.9   5.2  235  62 32   6.5   3.6 | -15.0   5.0  245  62 32   7.5   4.1
 17000 -13.9   7.0  235  60 31   7.6   4.2 | -13.9   7.0  245  59 31   7.7   4.2
 16500 -12.7   9.1  230  55 28   8.1   4.4 | -12.8   9.0  245  58 30   7.9   4.3
 16000 -11.5  11.3  230  50 26   8.3   4.6 | -11.6  11.1  245  57 30   7.9   4.3
 15500  -9.5  14.9  230  49 25   9.0   4.9 | -10.5  13.1  250  57 29   7.4   4.1
 15000  -8.2  17.2  230  48 25   8.5   4.6 |  -8.8  16.2  250  57 29   7.4   4.0
 14500  -7.0  19.4  230  51 26   7.9   4.3 |  -7.8  18.0  250  56 29   7.0   3.8
 14000  -5.9  21.4  235  54 28   7.6   4.2 |  -6.7  19.9  250  55 29   7.0   3.8
 13500  -4.8  23.4  235  54 28   6.6   3.6 |  -5.8  21.6  250  54 28   6.6   3.6
 13000  -3.8  25.2  240  53 27   6.7   3.7 |  -4.8  23.4  250  52 27   6.6   3.6
 12500  -2.8  27.0  240  52 27   7.0   3.8 |  -3.8  25.2  250  50 26   7.0   3.9
 12000  -1.8  28.8  245  51 26   7.0   3.9 |  -2.7  27.1  245  48 25   7.0   3.8
 11500  -0.8  30.6  245  49 25   6.2   3.4 |  -1.7  28.9  245  45 23   7.5   4.1
 11000   0.1  32.2  245  45 23   6.3   3.4 |  -0.6  30.9  245  43 22   7.5   4.1
 10500   1.0  33.8  245  42 22   6.4   3.5 |   0.5  32.9  240  41 21   7.4   4.1
 10250   1.5  34.7  240  40 21   6.4   3.5 |   1.1  34.0  240  40 20   7.4   4.1
 10000   2.0  35.6  240  39 20   7.7   4.2 |   1.6  34.9  240  39 20   7.4   4.1
  9750   2.5  36.5  240  37 19   7.6   4.1 |   2.1  35.8  235  38 19   7.4   4.1
  9500   3.0  37.4  240  36 18   6.5   3.6 |   2.7  36.9  235  37 19   7.3   4.0
  9250   3.5  38.3  235  34 18   6.9   3.8 |   3.2  37.8  235  36 19   8.0   4.4
  9000   4.0  39.2  235  33 17   6.6   3.6 |   3.7  38.7  230  35 18   5.4   2.9
  8750   4.4  39.9  235  32 16   5.3   2.9 |   4.0  39.2  230  34 18   5.1   2.8
  8500   4.7  40.5  230  30 15   4.3   2.3 |   4.5  40.1  225  33 17   7.4   4.0
  8250   5.0  41.0  230  28 15   5.4   3.0 |   5.0  41.0  225  32 17   7.2   4.0
  8000   5.3  41.5  225  27 14   2.1   1.2 |   5.5  41.9  220  31 16   5.6   3.1
  7750   5.2  41.4  220  23 12  -3.6  -2.0 |   5.8  42.4  220  30 15   3.7   2.1
  7500   4.8  40.6  220  20 10  -4.9  -2.7 |   6.0  42.8  220  27 14   3.5   1.9
  7250   4.5  40.1  215  17  9  -3.5  -1.9 |   6.3  43.3  215  25 13   5.8   3.2
  7000   4.0  39.2  215  15  8 -12.2  -6.7 |   6.5  43.7  215  22 11  -3.1  -1.7
  6750   2.7  36.9  210  11  6 -19.6 -10.7 |   5.7  42.3  215  18  9 -12.8  -7.0
  6500   1.4  34.5  195   8  4 -18.6 -10.2 |   4.9  40.8  215  14  7 -10.9  -6.0
  6250   0.1  32.2  175   6  3 -15.7  -8.6 |   4.1  39.4  210  10  5 -11.8  -6.5
  6000  -0.9  30.4  150   4  2 -12.1  -6.6 |   3.1  37.6  205   6  3 -15.0  -8.2
  5750  -1.6  29.1  115   3  2  -5.9  -3.2 |   1.8  35.2  195   2  1 -18.1 -10.0
  5500  -1.5  29.3  085   3  1  10.0   5.5 |   0.5  32.9  000   0  0 -17.0  -9.3
________________________________________________________________________________

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.

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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