Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 240100
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1800 MST Monday, February 23, 2015

This forecast is for Tuesday, February 24, 2015:

If the trigger temperature of 43.2 F/6.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 210 ft/min (1.1 m/s)
   Maximum height of thermals.................. 8428 ft MSL (3121 ft AGL)

Forecast maximum temperature................... 41.0 F/5.5 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6338 ft MSL (1032 ft AGL)
Thermal soaring outlook for Wednesday 02/25.... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 12214 ft MSL (6907 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 12707 ft MSL (7400 ft AGL)
Wave soaring outlook for Wednesday 02/25....... Poor

Remarks... None

Sunrise/Sunset.................... 06:39:58 / 17:44:37 MST
Total possible sunshine........... 11 hr 4 min 38 sec (664 min 38 sec)
Altitude of sun at 12:12:34 MST... 40.89 degrees

Upper air data from numerical model forecast valid on 02/24/2015 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 25458 ft MSL (20151 ft AGL)
Lifted condensation level....... 17512 ft MSL (12205 ft AGL)
Lifted index.................... +15.9
K index......................... -22.3

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -58.2 -72.8   290   35   18   1.1   0.6      M     M       M      M    M
 45000  -56.6 -69.9   285   35   18   1.3   0.7      M     M       M      M    M
 40000  -57.3 -71.1   290   18    9  -0.6  -0.3      M     M       M      M    M
 38000  -57.0 -70.6   300    9    4   2.7   1.5      M     M       M      M    M
 36000  -55.1 -67.2   070   10    5   2.7   1.5      M     M       M      M    M
 34000  -53.2 -63.8   080   24   12   8.1   4.4      M     M       M      M    M
 32000  -48.7 -55.7   080   30   15   7.4   4.1      M     M       M      M    M
 30000  -44.2 -47.6   075   35   18   7.0   3.8   32.7  90.8    20.7      M    M
 29000  -42.1 -43.8   075   33   17   7.0   3.9   31.5  88.6    20.1      M    M
 28000  -40.0 -40.0   075   31   16   7.0   3.9   30.4  86.7    19.5      M    M
 27000  -37.9 -36.2   070   29   15   7.0   3.9   29.5  85.1    19.0      M    M
 26000  -35.8 -32.4   070   26   13   6.9   3.8   28.3  83.0    18.4      M    M
 25000  -33.7 -28.7   065   23   12   7.0   3.8   27.2  81.0    17.7      M    M
 24000  -31.6 -24.9   060   21   11   6.9   3.8   26.3  79.3    17.2      M    M
 23000  -29.4 -20.9   060   19   10   7.4   4.1   25.3  77.6    16.6      M    M
 22000  -27.2 -17.0   060   18    9   7.4   4.1   24.4  76.0    16.0      M    M
 21000  -25.0 -13.0   060   17    9   7.4   4.1   23.7  74.6    15.6      M    M
 20000  -22.8  -9.0   060   15    8   7.5   4.1   22.8  73.0    15.0      M    M
 19500  -21.7  -7.1   055   14    7   7.5   4.1   22.4  72.3    14.7      M    M
 19000  -20.5  -4.9   055   13    7   7.5   4.1   22.0  71.6    14.5      M    M
 18500  -18.9  -2.0   055   11    6   6.9   3.8   21.5  70.6    14.1      M    M
 18000  -17.9  -0.2   050   10    5   6.5   3.6   20.9  69.6    13.7      M    M
 17500  -16.9   1.6   050    9    5   6.5   3.6   20.3  68.6    13.3      M    M
 17000  -16.0   3.2   040    8    4   6.4   3.5   19.8  67.6    12.9      M    M
 16500  -15.0   5.0   030    7    4   6.5   3.5   19.2  66.5    12.4      M    M
 16000  -14.1   6.6   025    7    4   5.6   3.1   18.6  65.4    12.0      M    M
 15500  -13.2   8.2   015    8    4   5.6   3.1   17.9  64.2    11.4      M    M
 15000  -12.4   9.7   010    8    4   5.2   2.9   17.2  62.9    10.8      M    M
 14500  -11.7  10.9   005   10    5   5.0   2.7   16.4  61.5    10.2      M    M
 14000  -10.9  12.4   005   11    6   4.5   2.5   15.6  60.1     9.5      M    M
 13500  -10.3  13.5   005   12    6   3.9   2.1   14.6  58.4     8.7      M    M
 13000   -9.7  14.5   005   14    7   3.5   1.9   13.7  56.7     7.9      M    M
 12500   -9.3  15.3   005   15    8   2.7   1.5   12.6  54.6     6.9      M    M
 12000   -8.9  16.0   005   17    9   2.8   1.5   11.4  52.6     5.9      M    M
 11500   -8.4  16.9   005   18    9   3.1   1.7   10.3  50.6     4.9      M    M
 11000   -7.9  17.8   005   18    9   3.4   1.9    9.3  48.7     3.9      M    M
 10500   -7.3  18.9   005   18    9   3.9   2.1    8.3  47.0     3.1      M    M
 10250   -7.1  19.2   005   17    9   4.1   2.3    7.9  46.2     2.6      M    M
 10000   -6.8  19.8   005   17    9   2.6   1.4    7.4  45.3     2.2      M    M
  9750   -6.6  20.1   005   17    9   4.2   2.3    6.8  44.3     1.7      M    M
  9500   -6.1  21.0   360   16    8   6.8   3.7    6.5  43.8     1.4      M    M
  9250   -5.7  21.7   360   15    8   5.8   3.2    6.3  43.3     1.1      M    M
  9000   -5.3  22.5   360   14    7   4.2   2.3    5.9  42.6     0.8      M    M
  8750   -5.0  23.0   360   13    7   5.0   2.7    5.5  41.8     0.4      M    M
  8500   -4.5  23.9   360   12    6   6.4   3.5    5.2  41.3     0.1      M    M
  8250   -4.0  24.8   360   11    6   6.6   3.6    4.9  40.8    -0.2    196  1.0
  8000   -3.5  25.7   005   11    6   7.2   4.0    4.7  40.4    -0.4    173  0.9
  7750   -3.0  26.6   010   11    6   7.7   4.2    4.5  40.1    -0.6    149  0.8
  7500   -2.3  27.9   015   11    6   8.0   4.4    4.4  39.9    -0.7    124  0.6
  7250   -1.8  28.8   020   11    6   7.0   3.8    4.2  39.5    -0.9     99  0.5
  7000   -1.3  29.7   020   10    5   6.0   3.3    3.9  39.1    -1.1     77  0.4
  6750   -0.8  30.6   020   10    5   7.9   4.3    3.7  38.7    -1.4     55  0.3
  6500   -0.4  31.3   015    8    4  -2.8  -1.5    3.3  38.0    -1.7     36  0.2
  6250   -1.3  29.7   355    4    2 -13.6  -7.5    1.8  35.2    -3.3     54  0.3
  6000   -2.1  28.2   295    3    2  -6.5  -3.6    0.2  32.4    -4.9     72  0.4
  5750   -2.9  26.8   250    6    3 -22.5 -12.3   -1.3  29.7    -6.5     90  0.5
  5500   -6.6  20.1   230    6    3 -80.4 -44.1   -5.7  21.8   -10.9    193  1.0

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

           02/24/2015 at 0800 MST          |       02/24/2015 at 1100 MST
                                           |
K index... -6.6  LI... +282.1              | K index... +0.7  LI... +282.4
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.6
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -57.9 -72.2  295  35 18   1.1   0.6 | -58.0 -72.4  295  32 16   1.1   0.6
 45000 -56.2 -69.2  285  36 18   1.3   0.7 | -56.3 -69.3  290  34 18   1.3   0.7
 40000 -56.9 -70.4  305  12  6  -0.6  -0.3 | -57.0 -70.6  315   9  5  -0.5  -0.3
 38000 -56.5 -69.7  015   6  3   2.4   1.3 | -56.5 -69.7  040   6  3   2.2   1.2
 36000 -55.1 -67.2  075  16  8   2.4   1.3 | -55.2 -67.4  075  15  8   2.2   1.2
 34000 -53.5 -64.3  085  28 15   6.7   3.7 | -53.6 -64.5  080  25 13   6.8   3.7
 32000 -49.1 -56.4  090  30 15   7.2   4.0 | -49.2 -56.6  085  25 13   7.4   4.1
 30000 -44.8 -48.6  090  31 16   7.3   4.0 | -44.8 -48.6  085  26 13   7.2   4.0
 29000 -42.7 -44.9  085  30 16   7.2   3.9 | -42.6 -44.7  085  26 14   7.1   3.9
 28000 -40.0 -40.0  080  29 15   7.2   3.9 | -40.0 -40.0  080  28 14   7.1   3.9
 27000 -37.8 -36.0  080  29 15   7.2   4.0 | -37.8 -36.0  075  29 15   7.3   4.0
 26000 -35.6 -32.1  075  29 15   7.3   4.0 | -35.6 -32.1  075  29 15   7.6   4.2
 25000 -33.5 -28.3  075  29 15   7.3   4.0 | -33.3 -27.9  080  29 15   7.6   4.2
 24000 -31.3 -24.3  075  30 15   7.3   4.0 | -31.1 -24.0  080  28 15   7.6   4.2
 23000 -29.2 -20.6  070  27 14   7.1   3.9 | -29.0 -20.2  080  26 14   6.9   3.8
 22000 -27.1 -16.8  065  24 12   7.1   3.9 | -26.9 -16.4  075  24 12   6.9   3.8
 21000 -25.0 -13.0  060  20 11   7.2   4.0 | -24.9 -12.8  075  22 11   6.9   3.8
 20000 -22.8  -9.0  060  19 10   7.4   4.0 | -22.8  -9.0  070  19 10   6.9   3.8
 19500 -21.7  -7.1  060  19 10   7.4   4.1 | -21.8  -7.2  070  18  9   7.0   3.8
 19000 -20.6  -5.1  060  18  9   7.4   4.1 | -20.8  -5.4  070  16  8   7.0   3.8
 18500 -19.5  -3.1  060  17  9   7.4   4.0 | -19.7  -3.5  070  15  8   7.0   3.8
 18000 -18.4  -1.1  060  17  9   7.2   3.9 | -18.7  -1.7  070  14  7   6.9   3.8
 17500 -17.4   0.7  060  16  8   7.2   3.9 | -17.7   0.1  070  13  7   7.0   3.8
 17000 -16.3   2.7  060  15  8   7.2   4.0 | -16.7   1.9  070  13  6   6.5   3.6
 16500 -15.3   4.5  055  15  8   7.2   4.0 | -15.7   3.7  070  12  6   6.5   3.6
 16000 -14.2   6.4  055  14  7   6.7   3.7 | -14.8   5.4  070  11  6   6.5   3.6
 15500 -13.3   8.1  050  13  7   6.3   3.4 | -13.8   7.2  065  11  6   6.5   3.6
 15000 -11.9  10.6  045  13  7   5.3   2.9 | -12.4   9.7  060  12  6   6.3   3.5
 14500 -11.2  11.8  035  13  7   5.1   2.8 | -11.4  11.5  055  12  6   6.3   3.4
 14000 -10.4  13.3  030  13  7   4.5   2.4 | -10.5  13.1  050  13  7   4.4   2.4
 13500  -9.8  14.4  025  13  7   4.0   2.2 | -10.0  14.0  040  13  7   3.1   1.7
 13000  -9.2  15.4  015  14  7   3.1   1.7 |  -9.5  14.9  035  13  7   2.3   1.3
 12500  -8.9  16.0  015  15  8   2.1   1.2 |  -9.3  15.3  030  13  7   1.4   0.8
 12000  -8.6  16.5  010  16  8   1.8   1.0 |  -9.1  15.6  020  13  7   1.6   0.9
 11500  -8.4  16.9  010  16  8   1.4   0.8 |  -8.8  16.2  020  13  7   2.0   1.1
 11000  -8.1  17.4  005  16  8   2.1   1.1 |  -8.6  16.5  015  13  7   2.5   1.4
 10500  -7.7  18.1  005  16  8   2.8   1.6 |  -8.1  17.4  015  13  7   3.2   1.7
 10250  -7.5  18.5  360  15  8   2.7   1.5 |  -7.9  17.8  015  13  7   2.9   1.6
 10000  -7.3  18.9  360  15  8   3.0   1.6 |  -7.7  18.1  010  13  7   2.6   1.4
  9750  -7.0  19.4  360  15  8   4.9   2.7 |  -7.5  18.5  010  13  7   4.7   2.6
  9500  -6.5  20.3  360  14  7   5.9   3.2 |  -7.0  19.4  010  13  7   6.1   3.4
  9250  -6.1  21.0  360  14  7   5.6   3.1 |  -6.6  20.1  010  13  7   5.5   3.0
  9000  -5.7  21.7  005  13  7   5.4   3.0 |  -6.2  20.8  010  13  7   4.9   2.7
  8750  -5.2  22.6  005  13  7   6.9   3.8 |  -5.8  21.6  010  13  6   6.6   3.6
  8500  -4.6  23.7  005  13  7   8.1   4.5 |  -5.3  22.5  015  13  6   8.0   4.4
  8250  -4.0  24.8  010  13  6   7.6   4.2 |  -4.7  23.5  015  13  6   7.7   4.2
  8000  -3.5  25.7  010  12  6   7.5   4.1 |  -4.1  24.6  015  12  6   7.9   4.3
  7750  -2.9  26.8  015  12  6   7.6   4.1 |  -3.4  25.9  015  12  6   8.0   4.4
  7500  -2.3  27.9  015  11  6   7.1   3.9 |  -2.8  27.0  010  11  6   8.1   4.4
  7250  -1.8  28.8  010   9  5   6.4   3.5 |  -2.2  28.0  005   9  5   8.0   4.4
  7000  -1.4  29.5  005   7  3   5.8   3.2 |  -1.5  29.3  355   7  4   8.1   4.4
  6750  -0.9  30.4  345   4  2   6.9   3.8 |  -0.9  30.4  340   6  3   8.4   4.6
  6500  -0.6  30.9  300   3  2  -1.7  -0.9 |  -0.3  31.5  320   5  2   4.7   2.6
  6250  -1.2  29.8  270   4  2 -10.0  -5.5 |  -0.2  31.6  300   4  2   1.6   0.9
  6000  -1.8  28.8  250   5  3  -4.5  -2.5 |  -0.0  32.0  280   4  2   3.0   1.7
  5750  -2.4  27.7  235   7  4 -17.8  -9.8 |   0.1  32.2  255   4  2   1.3   0.7
  5500  -5.4  22.3  225   6  3 -66.7 -36.6 |  -0.1  31.8  240   4  2  -6.1  -3.3

           02/24/2015 at 1400 MST          |       02/24/2015 at 1700 MST
                                           |
K index... +6.7  LI... +281.0              | K index... +1.0  LI... +278.2
CAPE... 0.0  CIN... -1.1                   | 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 -57.5 -71.5  295  30 15   0.8   0.5 | -57.4 -71.3  295  29 15   1.4   0.7
 45000 -56.2 -69.2  285  29 15   1.0   0.5 | -55.3 -67.5  285  33 17   1.7   0.9
 40000 -57.0 -70.6  320  11  6  -0.6  -0.3 | -58.1 -72.6  325  21 11  -2.1  -1.1
 38000 -56.7 -70.1  005  10  5   2.5   1.4 | -58.2 -72.8  350  22 11   3.7   2.0
 36000 -55.0 -67.0  040  16  8   2.5   1.4 | -56.0 -68.8  360  25 13   3.7   2.0
 34000 -53.2 -63.8  055  23 12   7.5   4.1 | -53.2 -63.8  010  29 15   7.4   4.1
 32000 -48.9 -56.0  055  22 12   7.2   3.9 | -48.9 -56.0  015  29 15   7.3   4.0
 30000 -44.6 -48.3  055  22 11   6.8   3.7 | -44.6 -48.3  020  29 15   6.7   3.7
 29000 -42.5 -44.5  055  24 12   6.9   3.8 | -42.6 -44.7  025  29 15   6.7   3.7
 28000 -40.4 -40.7  055  26 13   6.9   3.8 | -40.5 -40.9  025  29 15   6.7   3.7
 27000 -38.4 -37.1  050  28 14   6.8   3.7 | -38.5 -37.3  025  28 15   6.6   3.6
 26000 -36.0 -32.8  055  27 14   8.0   4.4 | -36.2 -33.2  025  27 14   8.0   4.4
 25000 -33.6 -28.5  060  26 14   8.0   4.4 | -33.8 -28.8  025  25 13   8.0   4.4
 24000 -31.2 -24.2  065  25 13   8.0   4.4 | -31.4 -24.5  030  23 12   8.0   4.4
 23000 -29.0 -20.2  070  24 12   7.3   4.0 | -29.1 -20.4  030  22 11   7.8   4.3
 22000 -26.8 -16.2  065  22 12   7.3   4.0 | -26.7 -16.1  035  21 11   7.8   4.3
 21000 -24.6 -12.3  065  21 11   7.2   3.9 | -24.4 -11.9  035  20 10   7.7   4.2
 20000 -22.7  -8.9  065  18  9   6.4   3.5 | -22.4  -8.3  035  18  9   6.3   3.5
 19500 -21.7  -7.1  065  17  9   6.4   3.5 | -21.4  -6.5  035  16  8   6.4   3.5
 19000 -20.8  -5.4  065  15  8   6.4   3.5 | -20.5  -4.9  035  15  8   6.4   3.5
 18500 -19.3  -2.7  060  13  7   6.9   3.8 | -19.5  -3.1  035  14  7   6.4   3.5
 18000 -18.3  -0.9  060  12  6   7.2   3.9 | -18.6  -1.5  035  13  7   6.4   3.5
 17500 -17.2   1.0  060  11  6   7.1   3.9 | -17.1   1.2  025  12  6   6.4   3.5
 17000 -16.3   2.7  060  10  5   5.4   3.0 | -16.2   2.8  020  12  6   6.3   3.5
 16500 -15.5   4.1  060   9  5   5.6   3.1 | -15.2   4.6  020  11  6   6.3   3.5
 16000 -14.7   5.5  055   8  4   5.5   3.0 | -14.3   6.3  015  11  6   6.3   3.5
 15500 -13.9   7.0  050   7  4   5.5   3.0 | -13.4   7.9  010  11  5   6.3   3.4
 15000 -13.1   8.4  045   6  3   6.6   3.6 | -12.4   9.7  005  11  5   5.9   3.2
 14500 -12.0  10.4  035   7  4   7.3   4.0 | -11.7  10.9  355  11  5   5.5   3.0
 14000 -10.9  12.4  030   7  4   6.6   3.6 | -10.9  12.4  350  11  6   5.9   3.2
 13500 -10.1  13.8  025   8  4   5.2   2.9 |  -9.9  14.2  345  12  6   6.8   3.7
 13000  -9.3  15.3  020   9  5   4.6   2.5 |  -8.9  16.0  340  12  6   6.6   3.6
 12500  -8.8  16.2  015   9  5   2.3   1.3 |  -8.1  17.4  340  13  7   5.6   3.1
 12000  -8.4  16.9  010  10  5   2.3   1.3 |  -7.3  18.9  340  14  7   5.6   3.0
 11500  -8.1  17.4  005   9  5   1.9   1.1 |  -6.5  20.3  340  13  7   4.6   2.5
 11000  -7.8  18.0  360   9  5   2.3   1.2 |  -5.8  21.6  335  13  7   4.5   2.5
 10500  -7.4  18.7  355   8  4   3.0   1.7 |  -5.2  22.6  330  12  6   3.7   2.1
 10250  -7.2  19.0  355   8  4   3.3   1.8 |  -5.0  23.0  330  12  6   3.2   1.7
 10000  -7.0  19.4  355   7  4   2.2   1.2 |  -4.7  23.5  330  11  6   5.6   3.1
  9750  -6.8  19.8  355   7  4   3.7   2.0 |  -4.2  24.4  325  10  5   6.1   3.4
  9500  -6.4  20.5  350   7  3   5.8   3.2 |  -3.8  25.2  325  10  5   4.0   2.2
  9250  -6.0  21.2  350   6  3   5.2   2.9 |  -3.5  25.7  320   9  5   4.8   2.6
  9000  -5.6  21.9  350   6  3   4.5   2.4 |  -3.1  26.4  320   8  4   3.6   2.0
  8750  -5.3  22.5  350   5  3   5.2   2.8 |  -2.9  26.8  320   8  4   3.6   2.0
  8500  -4.9  23.2  350   5  3   6.3   3.5 |  -2.6  27.3  315   7  3   4.6   2.5
  8250  -4.4  24.1  350   5  2   6.2   3.4 |  -2.2  28.0  315   6  3   4.3   2.4
  8000  -3.9  25.0  350   4  2   6.1   3.3 |  -1.9  28.6  310   5  3   5.0   2.7
  7750  -3.4  25.9  350   4  2   7.1   3.9 |  -1.5  29.3  305   4  2   4.1   2.3
  7500  -2.8  27.0  350   3  2   8.1   4.5 |  -1.3  29.7  295   3  1   2.8   1.5
  7250  -2.2  28.0  345   2  1   7.9   4.3 |  -1.0  30.2  275   2  1   4.0   2.2
  7000  -1.6  29.1  315   2  1   7.8   4.3 |  -0.7  30.7  240   2  1   4.9   2.7
  6750  -0.9  30.4  275   2  1   8.7   4.7 |  -0.3  31.5  215   3  2   4.6   2.5
  6500  -0.2  31.6  245   3  2   8.0   4.4 |   0.0  32.0  200   4  2   4.8   2.6
  6250   0.3  32.5  235   4  2   6.3   3.4 |   0.4  32.7  200   6  3   5.4   3.0
  6000   0.8  33.4  230   5  2   7.2   4.0 |   0.8  33.4  200   7  4   5.6   3.1
  5750   1.2  34.2  225   6  3   4.6   2.5 |   1.3  34.3  200   8  4   5.6   3.1
  5500   1.3  34.3  220   6  3  -2.6  -1.4 |   1.6  34.9  200   9  5  -0.5  -0.3
________________________________________________________________________________

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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