Soaring Guidance
Issued by NWS Denver/Boulder, CO

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
000
UXUS97 KBOU 021219
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0519 MST Monday, March 2, 2015

This forecast is for Monday, March 2, 2015:

If the trigger temperature of 55.0 F/12.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 121 ft/min (0.6 m/s)
   Maximum height of thermals.................. 7064 ft MSL (1757 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 thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6378 ft MSL (1071 ft AGL)
Thermal soaring outlook for Tuesday 03/03...... Poor

Wave Soaring Index............................. Poor
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....................... 14889 ft MSL (9582 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 numerical model forecast valid on 03/02/2015 at 0500 MST

Freezing level.................. 8420 ft MSL (3113 ft AGL)
Additional freezing level....... 10119 ft MSL (4812 ft AGL)
Convective condensation level... 15277 ft MSL (9970 ft AGL)
Lifted condensation level....... 8745 ft MSL (3439 ft AGL)
Lifted index.................... +15.0
K index......................... +17.4

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  -60.3 -76.5   255   70   36   1.2   0.6      M     M       M      M    M
 45000  -58.5 -73.3   250   97   50   1.1   0.6      M     M       M      M    M
 40000  -58.8 -73.8   250  113   58  -0.2  -0.1      M     M       M      M    M
 38000  -57.3 -71.1   250  115   59   5.1   2.8      M     M       M      M    M
 36000  -54.3 -65.7   250  114   59   5.1   2.8      M     M       M      M    M
 34000  -50.9 -59.6   250  112   58   8.6   4.7      M     M       M      M    M
 32000  -45.9 -50.6   250  109   56   8.3   4.5      M     M       M      M    M
 30000  -40.6 -41.1   250  105   54   6.9   3.8   36.2  97.1    25.5      M    M
 29000  -38.5 -37.3   250  102   52   6.8   3.7   34.9  94.8    24.9      M    M
 28000  -36.5 -33.7   250   99   51   6.8   3.7   33.8  92.8    24.3      M    M
 27000  -34.5 -30.1   250   95   49   6.5   3.6   32.8  91.0    23.8      M    M
 26000  -32.6 -26.7   250   90   46   6.2   3.4   31.3  88.3    22.9      M    M
 25000  -30.8 -23.4   250   85   44   6.2   3.4   29.9  85.9    22.1      M    M
 24000  -29.0 -20.2   255   80   41   6.3   3.4   28.7  83.7    21.4      M    M
 23000  -26.8 -16.2   250   66   34   7.5   4.1   27.7  81.9    20.8      M    M
 22000  -24.6 -12.3   245   50   26   7.5   4.1   26.9  80.5    20.4      M    M
 21000  -22.3  -8.1   230   36   18   6.6   3.6   26.2  79.2    20.0      M    M
 20000  -20.7  -5.3   235   36   19   5.5   3.0   24.6  76.3    18.9      M    M
 19500  -19.9  -3.8   240   36   19   5.5   3.0   23.9  75.0    18.3      M    M
 19000  -19.1  -2.4   240   37   19   5.5   3.0   23.2  73.7    17.8      M    M
 18500  -18.3  -0.9   245   37   19   5.6   3.1   22.5  72.4    17.3      M    M
 18000  -17.4   0.7   245   39   20   6.4   3.5   21.8  71.3    16.8      M    M
 17500  -16.4   2.5   250   42   22   6.3   3.4   21.2  70.2    16.4      M    M
 17000  -15.4   4.3   255   45   23   7.6   4.2   20.8  69.4    16.0      M    M
 16500  -14.3   6.3   255   47   24   7.8   4.3   20.4  68.7    15.8      M    M
 16000  -13.1   8.4   255   50   26   7.8   4.3   20.1  68.2    15.6      M    M
 15500  -11.4  11.5   255   52   27   7.8   4.3   19.6  67.2    15.2      M    M
 15000  -10.3  13.5   255   53   27   7.7   4.2   19.2  66.6    15.0      M    M
 14500   -9.1  15.6   255   53   27   7.7   4.2   18.9  66.0    14.8      M    M
 14000   -8.0  17.6   255   54   28   7.8   4.3   18.6  65.4    14.5      M    M
 13500   -6.8  19.8   250   53   27   8.0   4.4   18.3  64.9    14.3      M    M
 13000   -5.7  21.7   250   53   27   8.0   4.4   18.0  64.4    14.1      M    M
 12500   -4.5  23.9   250   50   26   7.8   4.3   17.7  63.8    13.8      M    M
 12000   -3.4  25.9   250   48   24   7.7   4.2   17.4  63.3    13.6      M    M
 11500   -2.3  27.9   250   44   23   7.2   3.9   17.0  62.6    13.3      M    M
 11000   -1.3  29.7   245   41   21   6.7   3.7   16.6  61.9    13.0      M    M
 10500   -0.5  31.1   245   38   19   4.7   2.6   15.9  60.6    12.3      M    M
 10250   -0.1  31.8   245   36   18   4.9   2.7   15.5  59.9    12.0      M    M
 10000    0.2  32.4   245   34   18   4.6   2.5   15.1  59.2    11.6      M    M
  9750    0.5  32.9   245   31   16   2.2   1.2   14.6  58.3    11.2      M    M
  9500    0.5  32.9   240   29   15   0.5   0.3   13.9  57.1    10.6      M    M
  9250    0.6  33.1   240   27   14   1.7   0.9   13.3  55.9     9.9      M    M
  9000    0.7  33.3   240   25   13  -1.4  -0.8   12.6  54.6     9.3      M    M
  8750    0.4  32.7   240   22   11  -4.7  -2.6   11.5  52.7     8.3      M    M
  8500    0.1  32.2   240   20   10  -3.9  -2.1   10.4  50.8     7.3      M    M
  8250   -0.2  31.6   235   18    9  -4.5  -2.4    9.4  48.9     6.3      M    M
  8000   -0.6  30.9   235   16    8  -6.8  -3.7    8.2  46.8     5.2      M    M
  7750   -1.2  29.8   230   13    7  -9.1  -5.0    6.8  44.3     3.9      M    M
  7500   -1.9  28.6   230   11    6 -10.0  -5.5    5.3  41.6     2.5      M    M
  7250   -2.6  27.3   235   10    5  -8.5  -4.6    3.9  38.9     1.1      M    M
  7000   -3.1  26.4   230    9    5  -7.8  -4.3    2.5  36.5    -0.2    322  1.6
  6750   -3.6  25.5   230    9    5  -4.6  -2.5    1.2  34.2    -1.4    330  1.7
  6500   -3.8  25.2   220   10    5  -2.3  -1.3    0.3  32.6    -2.3    328  1.7
  6250   -4.1  24.6   210   10    5  -6.2  -3.4   -0.8  30.6    -3.4    329  1.7
  6000   -4.6  23.7   195   10    5  -7.9  -4.3   -2.0  28.3    -4.7    338  1.7
  5750   -5.2  22.6   180   10    5  -6.4  -3.5   -3.3  26.0    -5.9    347  1.8
  5500   -5.6  21.9   170    7    4  -5.7  -3.1   -4.5  23.9    -7.1    353  1.8

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

           03/02/2015 at 0800 MST          |       03/02/2015 at 1100 MST
                                           |
K index... +10.5  LI... +276.7             | K index... +0.5  LI... +276.5
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 -60.7 -77.3  255  74 38   1.9   1.0 | -60.7 -77.3  255  74 38   1.0   0.5
 45000 -57.9 -72.2  250 102 53   1.9   1.1 | -59.2 -74.6  250 103 53   0.8   0.4
 40000 -59.7 -75.5  245 116 60  -1.2  -0.7 | -59.5 -75.1  240 113 58  -0.2  -0.1
 38000 -58.3 -72.9  245 119 61   5.8   3.2 | -57.6 -71.7  240 115 59   5.8   3.2
 36000 -54.8 -66.6  245 119 61   5.8   3.2 | -54.1 -65.4  240 115 59   5.8   3.2
 34000 -51.1 -60.0  240 118 61   8.5   4.7 | -50.4 -58.7  240 113 58   8.0   4.4
 32000 -46.1 -51.0  240 108 56   8.3   4.5 | -45.7 -50.3  235 106 55   7.9   4.3
 30000 -40.6 -41.1  240 100 51   7.9   4.3 | -40.8 -41.4  235 101 52   8.8   4.8
 29000 -38.3 -36.9  245 100 51   7.9   4.3 | -37.5 -35.5  235  99 51   8.8   4.8
 28000 -35.9 -32.6  245 100 51   7.9   4.3 | -34.9 -30.8  235  98 51   8.8   4.8
 27000 -33.6 -28.5  245 100 52   7.0   3.8 | -32.3 -26.1  235  97 50   7.8   4.3
 26000 -31.8 -25.2  245  94 49   5.9   3.2 | -30.1 -22.2  235  95 49   7.1   3.9
 25000 -30.0 -22.0  250  89 46   5.9   3.2 | -28.0 -18.4  240  93 48   7.1   3.9
 24000 -28.3 -18.9  250  83 43   5.9   3.3 | -25.9 -14.6  240  91 47   6.9   3.8
 23000 -26.4 -15.5  250  72 37   6.4   3.5 | -24.2 -11.6  240  85 44   5.3   2.9
 22000 -24.5 -12.1  250  60 31   6.4   3.5 | -22.7  -8.9  240  78 40   5.3   2.9
 21000 -22.6  -8.7  245  48 25   6.6   3.6 | -21.1  -6.0  245  71 37   5.2   2.9
 20000 -20.5  -4.9  245  42 22   6.9   3.8 | -19.5  -3.1  240  58 30   5.2   2.9
 19500 -19.5  -3.1  245  40 20   6.9   3.8 | -18.7  -1.7  240  51 26   5.2   2.9
 19000 -18.5  -1.3  245  37 19   6.9   3.8 | -17.9  -0.2  240  45 23   5.3   2.9
 18500 -17.5   0.5  245  34 18   6.9   3.8 | -17.1   1.2  235  38 20   5.6   3.1
 18000 -16.4   2.5  245  35 18   6.9   3.8 | -16.1   3.0  240  40 20   7.8   4.3
 17500 -15.4   4.3  250  38 20   6.9   3.8 | -14.9   5.2  245  44 23   7.8   4.3
 17000 -14.4   6.1  250  41 21   6.0   3.3 | -13.9   7.0  245  48 25   6.3   3.5
 16500 -13.6   7.5  250  43 22   5.9   3.2 | -13.0   8.6  245  49 25   6.1   3.4
 16000 -12.7   9.1  250  44 23   6.1   3.4 | -12.1  10.2  250  50 26   6.7   3.7
 15500 -11.3  11.7  250  46 24   6.6   3.6 | -10.4  13.3  250  54 28   7.7   4.2
 15000 -10.3  13.5  250  47 24   7.0   3.8 |  -9.3  15.3  250  56 29   7.0   3.9
 14500  -9.2  15.4  250  48 25   7.1   3.9 |  -8.3  17.1  250  57 29   6.7   3.7
 14000  -8.2  17.2  250  48 25   7.0   3.8 |  -7.3  18.9  250  58 30   6.9   3.8
 13500  -7.2  19.0  250  48 25   6.8   3.7 |  -6.3  20.7  250  56 29   7.1   3.9
 13000  -6.2  20.8  250  48 25   6.8   3.7 |  -5.3  22.5  250  54 28   7.2   4.0
 12500  -5.2  22.6  250  47 24   7.0   3.8 |  -4.2  24.4  250  52 27   7.6   4.2
 12000  -4.1  24.6  250  46 24   7.1   3.9 |  -3.1  26.4  250  49 25   7.5   4.1
 11500  -3.0  26.6  250  44 22   7.7   4.2 |  -2.0  28.4  250  46 23   7.1   3.9
 11000  -1.9  28.6  250  41 21   7.5   4.1 |  -1.0  30.2  250  41 21   7.1   3.9
 10500  -0.9  30.4  250  37 19   6.9   3.8 |  -0.0  32.0  250  38 19   6.5   3.6
 10250  -0.4  31.3  250  36 18   6.2   3.4 |   0.4  32.7  250  36 18   6.3   3.5
 10000   0.1  32.2  250  34 17   9.3   5.1 |   0.9  33.6  250  34 18   8.5   4.7
  9750   0.8  33.4  250  31 16   7.8   4.3 |   1.6  34.9  250  31 16   7.6   4.2
  9500   1.1  34.0  250  29 15   3.4   1.9 |   2.0  35.6  250  29 15   4.9   2.7
  9250   1.4  34.5  250  27 14   5.2   2.8 |   2.4  36.3  245  27 14   6.3   3.5
  9000   1.8  35.2  250  25 13   2.4   1.3 |   2.8  37.0  245  25 13   3.4   1.9
  8750   1.8  35.2  250  22 11  -0.7  -0.4 |   2.9  37.2  240  22 12   1.2   0.7
  8500   1.7  35.1  250  20 10  -0.7  -0.4 |   3.0  37.4  240  20 10   2.1   1.2
  8250   1.7  35.1  250  17  9  -0.6  -0.3 |   3.2  37.8  235  18  9   2.3   1.3
  8000   1.5  34.7  250  14  7  -5.2  -2.9 |   3.3  37.9  235  16  8  -0.5  -0.3
  7750   0.9  33.6  250  11  6  -9.0  -4.9 |   3.0  37.4  230  13  6  -4.6  -2.5
  7500   0.3  32.5  255   9  4  -7.7  -4.2 |   2.7  36.9  225  10  5  -4.5  -2.5
  7250  -0.3  31.5  260   6  3  -9.4  -5.2 |   2.3  36.1  215   8  4  -6.1  -3.4
  7000  -1.1  30.0  260   5  2 -11.8  -6.5 |   1.7  35.1  205   6  3  -9.9  -5.5
  6750  -2.0  28.4  260   3  2 -12.0  -6.6 |   0.9  33.6  190   4  2 -11.9  -6.5
  6500  -2.8  27.0  270   2  1 -11.7  -6.4 |   0.0  32.0  160   3  2 -12.6  -6.9
  6250  -3.7  25.3  275   2  1 -10.9  -6.0 |  -0.9  30.4  120   3  1 -10.7  -5.8
  6000  -4.4  24.1  260   2  1 -10.5  -5.7 |  -1.6  29.1  095   2  1 -10.3  -5.6
  5750  -5.2  22.6  245   2  1 -10.1  -5.5 |  -2.3  27.9  065   2  1  -7.2  -4.0
  5500  -5.9  21.4  200   3  1 -10.4  -5.7 |  -2.4  27.7  040   3  1   7.0   3.8

           03/02/2015 at 1400 MST          |       03/02/2015 at 1700 MST
                                           |
K index... +5.7  LI... +275.8              | K index... +7.8  LI... +275.4
CAPE... 0.0  CIN... -0.0                   | 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 -61.3 -78.3  245  70 36   1.9   1.1 | -62.3 -80.1  245  73 38   1.3   0.7
 45000 -58.4 -73.1  245 103 53   1.7   0.9 | -60.4 -76.7  240 101 52   1.2   0.7
 40000 -58.8 -73.8  240 121 62  -0.4  -0.2 | -59.3 -74.7  240 127 66   0.7   0.4
 38000 -57.0 -70.6  240 123 63   6.0   3.3 | -56.8 -70.2  235 130 67   6.8   3.7
 36000 -53.4 -64.1  235 120 62   6.0   3.3 | -52.8 -63.0  230 126 65   6.8   3.7
 34000 -49.6 -57.3  235 118 61   8.1   4.4 | -48.5 -55.3  225 123 63   9.0   4.9
 32000 -44.9 -48.8  235 117 60   7.9   4.4 | -43.2 -45.8  230 121 62   8.9   4.9
 30000 -39.6 -39.3  240 114 59   7.6   4.2 | -38.0 -36.4  230 120 62   6.1   3.3
 29000 -37.3 -35.1  240 111 57   7.6   4.1 | -36.1 -33.0  235 118 61   6.4   3.5
 28000 -35.1 -31.2  240 107 55   7.6   4.2 | -33.7 -28.7  235 116 60   6.4   3.5
 27000 -32.8 -27.0  240 104 53   7.4   4.1 | -31.8 -25.2  235 114 59   6.5   3.6
 26000 -30.6 -23.1  240 100 52   7.2   3.9 | -29.8 -21.6  235 111 57   6.7   3.7
 25000 -28.5 -19.3  240  97 50   7.2   3.9 | -27.8 -18.0  235 107 55   6.7   3.7
 24000 -26.3 -15.3  240  93 48   7.2   4.0 | -25.8 -14.4  235 103 53   6.8   3.7
 23000 -24.5 -12.1  240  88 45   5.8   3.2 | -24.1 -11.4  240  99 51   5.4   3.0
 22000 -22.8  -9.0  240  82 42   5.8   3.2 | -22.5  -8.5  240  94 48   5.4   3.0
 21000 -21.1  -6.0  240  76 39   5.8   3.2 | -20.8  -5.4  240  89 46   5.4   3.0
 20000 -19.4  -2.9  240  67 34   5.7   3.1 | -19.2  -2.6  240  83 43   5.4   2.9
 19500 -18.5  -1.3  235  62 32   5.7   3.1 | -18.4  -1.1  245  79 41   5.4   2.9
 19000 -17.6   0.3  235  57 30   5.7   3.1 | -17.7   0.1  245  76 39   5.4   2.9
 18500 -16.8   1.8  235  53 27   5.7   3.1 | -16.9   1.6  245  73 37   5.4   2.9
 18000 -15.7   3.7  235  54 28   8.2   4.5 | -16.0   3.2  245  70 36   5.7   3.1
 17500 -14.5   5.9  240  59 30   8.0   4.4 | -15.2   4.6  245  68 35   5.8   3.2
 17000 -13.4   7.9  240  63 33   6.2   3.4 | -14.4   6.1  250  67 34   6.2   3.4
 16500 -12.6   9.3  240  61 32   5.5   3.0 | -13.4   7.9  250  65 34   6.8   3.7
 16000 -11.8  10.8  240  59 31   5.8   3.2 | -12.4   9.7  250  64 33   6.8   3.7
 15500 -10.3  13.5  240  59 30   7.1   3.9 | -11.4  11.5  250  62 32   7.2   4.0
 15000  -9.3  15.3  245  59 30   7.1   3.9 |  -9.8  14.4  250  59 31   7.1   3.9
 14500  -8.3  17.1  245  58 30   7.2   4.0 |  -8.8  16.2  250  57 29   6.8   3.7
 14000  -7.2  19.0  245  58 30   7.2   4.0 |  -7.8  18.0  250  55 28   6.8   3.8
 13500  -6.1  21.0  245  56 29   7.3   4.0 |  -6.7  19.9  250  52 27   7.4   4.1
 13000  -5.1  22.8  250  54 28   7.3   4.0 |  -5.6  21.9  250  48 25   7.4   4.1
 12500  -4.0  24.8  250  51 26   7.4   4.1 |  -4.6  23.7  250  45 23   7.5   4.1
 12000  -2.9  26.8  250  48 25   7.4   4.1 |  -3.5  25.7  250  43 22   7.5   4.1
 11500  -1.8  28.8  245  45 23   8.0   4.4 |  -2.3  27.9  250  40 21   8.0   4.4
 11000  -0.6  30.9  245  42 22   8.0   4.4 |  -1.1  30.0  245  38 20   8.1   4.4
 10500   0.4  32.7  245  39 20   7.1   3.9 |  -0.0  32.0  245  36 18   7.2   3.9
 10250   1.0  33.8  240  38 19   7.3   4.0 |   0.5  32.9  245  35 18   7.4   4.1
 10000   1.5  34.7  240  36 19   8.8   4.9 |   1.1  34.0  240  34 18   8.0   4.4
  9750   2.2  36.0  240  35 18   8.1   4.4 |   1.7  35.1  240  34 17   8.6   4.7
  9500   2.7  36.9  240  33 17   6.4   3.5 |   2.3  36.1  240  33 17   8.7   4.8
  9250   3.2  37.8  235  31 16   7.0   3.8 |   2.9  37.2  235  32 16   9.1   5.0
  9000   3.6  38.5  235  29 15   6.4   3.5 |   3.6  38.5  235  31 16   7.7   4.2
  8750   4.0  39.2  230  28 14   4.5   2.5 |   4.1  39.4  230  31 16   7.0   3.8
  8500   4.3  39.7  230  25 13   3.4   1.8 |   4.6  40.3  230  29 15   7.7   4.2
  8250   4.5  40.1  230  23 12   4.3   2.3 |   5.1  41.2  225  28 15   7.9   4.3
  8000   4.8  40.6  225  21 11   1.9   1.0 |   5.7  42.3  225  27 14   6.7   3.7
  7750   4.7  40.5  220  18  9  -2.4  -1.3 |   6.0  42.8  225  25 13   3.0   1.7
  7500   4.5  40.1  215  16  8  -3.2  -1.7 |   6.1  43.0  220  23 12   1.0   0.5
  7250   4.2  39.6  210  13  7  -3.0  -1.6 |   6.2  43.2  220  21 11   3.2   1.7
  7000   3.8  38.8  205  11  6 -10.5  -5.8 |   6.3  43.3  215  19 10  -3.5  -1.9
  6750   2.8  37.0  200   8  4 -14.8  -8.1 |   5.6  42.1  215  16  8 -12.3  -6.8
  6500   1.8  35.2  190   5  3 -13.4  -7.3 |   4.7  40.5  215  12  6 -12.3  -6.7
  6250   0.8  33.4  170   3  2 -11.5  -6.3 |   3.8  38.8  210   8  4 -12.4  -6.8
  6000   0.1  32.2  135   2  1  -9.3  -5.1 |   2.8  37.0  210   5  2 -16.3  -8.9
  5750  -0.6  30.9  090   2  1  -6.1  -3.3 |   1.6  34.9  195   2  1 -12.3  -6.7
  5500  -0.6  30.9  050   2  1   5.3   2.9 |   1.1  34.0  000   0  0  -2.8  -1.5
________________________________________________________________________________

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



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.