Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 280115
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1815 MST Friday, February 27, 2015

This forecast is for Saturday, February 28, 2015:

If the trigger temperature of 38.8 F/3.8 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 254 ft/min (1.3 m/s)
   Maximum height of thermals.................. 6810 ft MSL (1503 ft AGL)

Forecast maximum temperature................... 22.0 F/-6.0 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................. 6307 ft MSL (1000 ft AGL)
Thermal soaring outlook for Sunday 03/01....... Fair

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)................ Neither
Potential height of wave....................... 52647 ft MSL (47340 ft AGL)
Wave soaring outlook for Sunday 03/01.......... Poor

Remarks...

Sunrise/Sunset.................... 06:34:13 / 17:49:04 MST
Total possible sunshine........... 11 hr 14 min 51 sec (674 min 51 sec)
Altitude of sun at 12:11:53 MST... 42.39 degrees

Upper air data from numerical model forecast valid on 02/28/2015 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 14007 ft MSL (8700 ft AGL)
Lifted condensation level....... 8469 ft MSL (3162 ft AGL)
Lifted index.................... +12.9
K index......................... +13.5

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  -53.6 -64.5   275   55   28   1.1   0.6      M     M       M      M    M
 45000  -52.0 -61.6   270   53   28   1.1   0.6      M     M       M      M    M
 40000  -51.1 -60.0   270   57   29   0.5   0.3      M     M       M      M    M
 38000  -50.8 -59.4   270   58   30   0.3   0.2      M     M       M      M    M
 36000  -51.6 -60.9   270   57   30  -1.3  -0.7      M     M       M      M    M
 34000  -52.3 -62.1   265   57   29  -1.3  -0.7      M     M       M      M    M
 32000  -52.0 -61.6   265   53   27   1.6   0.9      M     M       M      M    M
 30000  -51.1 -60.0   265   49   25   1.6   0.9      M     M       M      M    M
 29000  -50.3 -58.5   260   47   24   4.7   2.6   23.5  74.2    21.8      M    M
 28000  -48.9 -56.0   260   45   23   4.5   2.5   21.2  70.2    20.4      M    M
 27000  -47.6 -53.7   260   43   22   4.5   2.5   19.2  66.6    19.1      M    M
 26000  -46.2 -51.2   260   41   21   5.7   3.1   17.3  63.2    17.9      M    M
 25000  -44.1 -47.4   260   40   20   7.1   3.9   16.2  61.1    17.2      M    M
 24000  -42.0 -43.6   260   38   20   7.2   3.9   15.2  59.4    16.6      M    M
 23000  -39.8 -39.6   260   37   19   7.7   4.2   14.4  57.9    16.1      M    M
 22000  -37.4 -35.3   260   36   19   8.2   4.5   13.7  56.6    15.8      M    M
 21000  -34.9 -30.8   260   36   18   8.2   4.5   13.1  55.6    15.5      M    M
 20000  -32.5 -26.5   260   35   18   7.5   4.1   12.5  54.6    15.2      M    M
 19500  -31.4 -24.5   255   34   17   7.6   4.2   12.1  53.8    14.9      M    M
 19000  -30.3 -22.5   255   32   17   7.6   4.2   11.7  53.1    14.7      M    M
 18500  -29.1 -20.4   255   31   16   7.6   4.2   11.4  52.4    14.4      M    M
 18000  -27.4 -17.3   255   29   15   8.4   4.6   10.9  51.6    14.1      M    M
 17500  -26.1 -15.0   255   29   15   8.9   4.9   10.7  51.3    14.1      M    M
 17000  -24.7 -12.5   250   28   14   8.9   4.9   10.6  51.1    14.0      M    M
 16500  -23.5 -10.3   250   27   14   8.5   4.7   10.4  50.7    13.9      M    M
 16000  -22.2  -8.0   255   26   14   8.6   4.7   10.2  50.3    13.8      M    M
 15500  -21.0  -5.8   255   25   13   7.8   4.3    9.9  49.9    13.7      M    M
 15000  -19.8  -3.6   260   23   12   7.9   4.3    9.6  49.3    13.4      M    M
 14500  -18.6  -1.5   260   22   11   8.0   4.4    9.3  48.8    13.2      M    M
 14000  -17.4   0.7   265   20   10   8.0   4.4    9.0  48.2    13.0      M    M
 13500  -16.2   2.8   265   18    9   7.3   4.0    8.7  47.7    12.8      M    M
 13000  -15.2   4.6   270   16    8   7.0   3.9    8.2  46.8    12.5      M    M
 12500  -14.2   6.4   275   14    7   7.5   4.1    7.8  46.1    12.1      M    M
 12000  -13.0   8.6   280   13    7   7.8   4.3    7.5  45.5    11.9      M    M
 11500  -11.9  10.6   280   12    6   6.2   3.4    7.1  44.8    11.6      M    M
 11000  -11.1  12.0   285   10    5   5.5   3.0    6.4  43.6    11.0      M    M
 10500  -10.3  13.5   295    8    4   5.3   2.9    5.7  42.3    10.4      M    M
 10250   -9.9  14.2   295    8    4   5.1   2.8    5.4  41.7    10.1      M    M
 10000   -9.5  14.9   295    7    4   5.4   3.0    5.0  41.0     9.7      M    M
  9750   -9.1  15.6   300    6    3   5.9   3.2    4.7  40.5     9.5      M    M
  9500   -8.7  16.3   305    6    3   5.2   2.8    4.4  39.9     9.2      M    M
  9250   -8.3  17.1   305    5    3   4.6   2.5    4.0  39.2     8.8      M    M
  9000   -8.0  17.6   310    5    3   4.9   2.7    3.6  38.5     8.5      M    M
  8750   -7.6  18.3   315    5    2   2.4   1.3    3.2  37.7     8.1      M    M
  8500   -7.6  18.3   315    4    2   0.9   0.5    2.5  36.5     7.5      M    M
  8250   -7.4  18.7   320    4    2   2.5   1.4    1.9  35.3     6.9      M    M
  8000   -7.3  18.9   325    4    2   0.1   0.0    1.2  34.2     6.3      M    M
  7750   -7.5  18.5   330    4    2  -5.8  -3.2    0.3  32.5     5.4      M    M
  7500   -8.1  17.4   335    4    2  -8.4  -4.6   -1.1  30.1     4.1      M    M
  7250   -8.7  16.3   335    4    2  -7.8  -4.3   -2.4  27.6     2.8      M    M
  7000   -9.3  15.3   335    4    2 -10.0  -5.5   -3.8  25.1     1.4      M    M
  6750  -10.1  13.8   345    4    2 -10.6  -5.8   -5.4  22.2    -0.2    256  1.3
  6500  -10.9  12.4   345    4    2 -10.3  -5.7   -6.9  19.5    -1.6    271  1.4
  6250  -11.6  11.1   345    4    2  -6.5  -3.6   -8.4  16.9    -3.1    285  1.4
  6000  -11.8  10.8   340    5    2  -2.1  -1.1   -9.4  15.1    -4.1    285  1.4
  5750  -12.0  10.4   335    5    2  -2.8  -1.5  -10.3  13.4    -5.0    283  1.4
  5500  -12.2  10.0   315    4    2  -2.1  -1.2  -11.2  11.8    -5.9    281  1.4

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

           02/28/2015 at 0800 MST          |       02/28/2015 at 1100 MST
                                           |
K index... +7.2  LI... +276.1              | K index... -2.5  LI... +277.9
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.2
                                           |
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 -54.3 -65.7  270  57 29   1.2   0.7 | -54.4 -65.9  270  59 30   1.1   0.6
 45000 -52.4 -62.3  270  56 29   1.2   0.7 | -52.6 -62.7  265  61 31   1.1   0.6
 40000 -51.2 -60.2  270  61 31   0.7   0.4 | -52.4 -62.3  265  68 35  -0.0  -0.0
 38000 -50.8 -59.4  270  63 33  -0.3  -0.2 | -52.4 -62.3  265  72 37   0.3   0.2
 36000 -51.3 -60.3  270  66 34  -0.8  -0.5 | -52.2 -62.0  265  76 39   0.5   0.2
 34000 -51.8 -61.2  270  68 35  -0.8  -0.5 | -51.9 -61.4  265  81 42   0.5   0.2
 32000 -51.7 -61.1  270  64 33   0.9   0.5 | -51.2 -60.2  265  79 41   1.5   0.8
 30000 -51.1 -60.0  270  58 30   0.9   0.5 | -50.2 -58.4  265  72 37   1.4   0.8
 29000 -50.2 -58.4  275  55 28   4.5   2.5 | -49.3 -56.7  260  68 35   4.0   2.2
 28000 -48.8 -55.8  275  55 28   4.6   2.5 | -48.1 -54.6  260  64 33   4.0   2.2
 27000 -47.5 -53.5  280  55 28   4.6   2.5 | -46.9 -52.4  260  60 31   4.0   2.2
 26000 -45.9 -50.6  285  54 28   8.2   4.5 | -45.4 -49.7  255  56 29   8.8   4.8
 25000 -43.3 -45.9  280  53 27   8.7   4.8 | -42.8 -45.0  255  52 27   8.6   4.7
 24000 -40.7 -41.3  280  51 26   8.7   4.8 | -40.3 -40.5  255  49 25   8.6   4.7
 23000 -38.1 -36.6  280  49 25   8.1   4.5 | -37.7 -35.9  260  45 23   9.0   4.9
 22000 -35.7 -32.3  280  44 23   8.0   4.4 | -35.0 -31.0  260  40 20   9.0   4.9
 21000 -33.3 -27.9  275  39 20   8.0   4.4 | -32.3 -26.1  265  35 18   8.9   4.9
 20000 -31.1 -24.0  275  35 18   6.6   3.6 | -29.7 -21.5  265  33 17   8.2   4.5
 19500 -30.1 -22.2  275  33 17   6.7   3.6 | -28.5 -19.3  260  34 17   8.2   4.5
 19000 -29.1 -20.4  270  31 16   6.7   3.7 | -27.3 -17.1  260  35 18   8.2   4.5
 18500 -28.1 -18.6  270  29 15   6.7   3.7 | -26.1 -15.0  260  36 18   8.2   4.5
 18000 -27.1 -16.8  270  27 14   6.8   3.7 | -24.8 -12.6  255  37 19   8.1   4.5
 17500 -26.1 -15.0  270  25 13   7.4   4.1 | -23.6 -10.5  255  36 19   8.1   4.4
 17000 -25.0 -13.0  270  24 12   7.3   4.0 | -22.4  -8.3  260  35 18   8.1   4.5
 16500 -23.9 -11.0  270  23 12   8.0   4.4 | -21.2  -6.2  260  34 18   7.6   4.2
 16000 -22.7  -8.9  270  22 11   7.9   4.4 | -19.5  -3.1  260  32 16   7.6   4.2
 15500 -21.5  -6.7  270  21 11   8.0   4.4 | -18.5  -1.3  260  29 15   7.0   3.8
 15000 -19.7  -3.5  270  19 10   8.2   4.5 | -17.4   0.7  260  27 14   7.1   3.9
 14500 -18.5  -1.3  270  18  9   7.4   4.1 | -16.5   2.3  255  24 13   5.9   3.2
 14000 -17.4   0.7  275  17  9   7.5   4.1 | -15.6   3.9  255  22 11   6.1   3.4
 13500 -16.3   2.7  275  16  8   7.3   4.0 | -14.7   5.5  255  19 10   5.3   2.9
 13000 -15.3   4.5  280  14  7   7.3   4.0 | -14.0   6.8  255  16  8   5.2   2.9
 12500 -14.2   6.4  280  13  7   6.8   3.7 | -13.2   8.2  250  13  7   5.5   3.0
 12000 -13.2   8.2  290  12  6   6.7   3.7 | -12.4   9.7  250  10  5   5.6   3.1
 11500 -12.3   9.9  295  10  5   6.4   3.5 | -11.6  11.1  250   7  4   4.9   2.7
 11000 -11.3  11.7  300   9  5   6.5   3.6 | -10.9  12.4  250   5  3   4.9   2.7
 10500 -10.5  13.1  305   8  4   4.8   2.6 | -10.2  13.6  255   4  2   4.0   2.2
 10250 -10.1  13.8  310   8  4   4.1   2.3 |  -9.9  14.2  260   3  1   3.8   2.1
 10000  -9.8  14.4  315   7  4   6.0   3.3 |  -9.6  14.7  270   2  1   4.5   2.5
  9750  -9.3  15.3  320   7  3   6.4   3.5 |  -9.3  15.3  295   2  1   4.3   2.4
  9500  -8.9  16.0  325   6  3   4.3   2.4 |  -9.0  15.8  315   2  1   3.5   1.9
  9250  -8.6  16.5  330   6  3   4.5   2.4 |  -8.8  16.2  335   2  1   3.8   2.1
  9000  -8.3  17.1  330   6  3   4.3   2.3 |  -8.5  16.7  345   2  1   3.1   1.7
  8750  -8.0  17.6  335   6  3   2.7   1.5 |  -8.3  17.1  355   3  1   1.0   0.5
  8500  -7.9  17.8  340   6  3   1.5   0.8 |  -8.3  17.1  360   4  2  -0.2  -0.1
  8250  -7.7  18.1  340   7  3   2.2   1.2 |  -8.3  17.1  360   4  2   0.9   0.5
  8000  -7.6  18.3  345   7  3   0.7   0.4 |  -8.3  17.1  360   5  3  -2.1  -1.2
  7750  -7.7  18.1  345   7  3  -3.2  -1.8 |  -8.6  16.5  360   6  3  -5.6  -3.1
  7500  -8.0  17.6  350   7  3  -5.0  -2.8 |  -9.0  15.8  005   7  3  -5.0  -2.7
  7250  -8.4  16.9  350   7  3  -6.0  -3.3 |  -9.4  15.1  005   7  4  -5.7  -3.1
  7000  -9.0  15.8  350   6  3  -9.9  -5.4 |  -9.9  14.2  005   8  4  -7.4  -4.0
  6750  -9.9  14.2  350   6  3 -12.8  -7.0 | -10.5  13.1  005   8  4  -8.4  -4.6
  6500 -10.9  12.4  345   6  3 -14.9  -8.2 | -11.2  11.8  360   7  4  -8.9  -4.9
  6250 -11.9  10.6  340   5  3  -6.6  -3.6 | -11.6  11.1  360   7  3   2.3   1.3
  6000 -11.9  10.6  330   5  2   1.6   0.9 | -10.9  12.4  355   6  3  11.0   6.0
  5750 -11.9  10.6  320   4  2  -2.5  -1.4 | -10.3  13.5  355   5  2   7.8   4.3
  5500 -12.1  10.2  300   4  2  -1.0  -0.6 |  -9.5  14.9  355   4  2  13.7   7.5

           02/28/2015 at 1400 MST          |       02/28/2015 at 1700 MST
                                           |
K index... +10.2  LI... +279.0             | K index... +11.3  LI... +278.6
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 -54.5 -66.1  270  63 32   1.0   0.6 | -55.0 -67.0  270  61 31   1.3   0.7
 45000 -52.9 -63.2  265  64 33   1.0   0.6 | -53.1 -63.6  265  62 32   1.3   0.7
 40000 -52.7 -62.9  265  74 38   0.0   0.0 | -52.9 -63.2  265  78 40  -0.1  -0.0
 38000 -52.7 -62.9  265  79 41  -0.1  -0.1 | -52.9 -63.2  265  86 44   0.2   0.1
 36000 -52.8 -63.0  260  86 44  -0.1  -0.1 | -52.8 -63.0  265  99 51   0.2   0.1
 34000 -52.9 -63.2  260  93 48  -0.1  -0.0 | -52.7 -62.9  260 115 59  -0.2  -0.1
 32000 -51.1 -60.0  260  92 47   3.8   2.1 | -50.0 -58.0  260 119 61   5.3   2.9
 30000 -48.8 -55.8  255  88 45   3.7   2.0 | -46.8 -52.2  260 122 63   5.3   2.9
 29000 -47.6 -53.7  255  84 43   4.3   2.3 | -45.3 -49.5  260 114 59   5.2   2.9
 28000 -46.3 -51.3  250  78 40   4.3   2.3 | -43.7 -46.7  260 103 53   5.2   2.9
 27000 -45.0 -49.0  250  73 37   4.2   2.3 | -42.1 -43.8  260  91 47   5.2   2.9
 26000 -43.4 -46.1  245  69 35   8.8   4.8 | -40.6 -41.1  255  80 41   4.7   2.6
 25000 -40.9 -41.6  245  66 34   8.3   4.6 | -39.2 -38.6  255  73 37   4.8   2.6
 24000 -38.5 -37.3  245  64 33   8.3   4.6 | -37.8 -36.0  250  65 33   4.7   2.6
 23000 -36.0 -32.8  245  62 32   8.5   4.6 | -36.1 -33.0  250  58 30   9.3   5.1
 22000 -33.4 -28.1  245  56 29   8.5   4.6 | -33.3 -27.9  250  54 28   9.2   5.0
 21000 -30.9 -23.6  240  51 26   8.5   4.7 | -30.6 -23.1  250  50 26   9.1   5.0
 20000 -28.4 -19.1  245  48 25   8.4   4.6 | -28.1 -18.6  250  44 23   7.5   4.1
 19500 -27.1 -16.8  245  47 24   8.4   4.6 | -27.0 -16.6  250  42 21   7.5   4.1
 19000 -25.9 -14.6  250  46 24   8.4   4.6 | -25.9 -14.6  255  39 20   7.5   4.1
 18500 -24.6 -12.3  255  46 24   8.4   4.6 | -24.7 -12.5  255  36 18   7.5   4.1
 18000 -23.4 -10.1  260  46 24   8.1   4.5 | -23.1  -9.6  260  32 16   7.5   4.1
 17500 -22.3  -8.1  260  44 22   7.5   4.1 | -22.0  -7.6  260  29 15   7.5   4.1
 17000 -21.1  -6.0  260  41 21   7.6   4.2 | -20.8  -5.4  265  27 14   7.7   4.2
 16500 -19.5  -3.1  255  37 19   7.2   3.9 | -19.7  -3.5  260  25 13   7.9   4.3
 16000 -18.5  -1.3  255  35 18   7.1   3.9 | -18.5  -1.3  255  23 12   7.9   4.3
 15500 -17.6   0.3  250  32 17   5.6   3.1 | -17.4   0.7  250  22 11   7.2   4.0
 15000 -16.7   1.9  245  29 15   5.8   3.2 | -16.3   2.7  245  22 11   7.5   4.1
 14500 -16.0   3.2  240  27 14   4.6   2.5 | -15.4   4.3  240  22 11   5.5   3.0
 14000 -15.3   4.5  235  24 13   4.7   2.6 | -14.6   5.7  235  22 11   5.7   3.1
 13500 -14.6   5.7  225  22 11   3.8   2.1 | -13.8   7.2  225  22 11   4.5   2.5
 13000 -14.1   6.6  220  19 10   3.7   2.0 | -13.2   8.2  220  20 10   4.5   2.5
 12500 -13.5   7.7  215  16  8   4.1   2.3 | -12.6   9.3  215  19 10   2.2   1.2
 12000 -12.9   8.8  205  14  7   4.2   2.3 | -12.4   9.7  205  16  8   1.7   0.9
 11500 -12.2  10.0  195  12  6   5.2   2.9 | -12.1  10.2  195  13  7   2.0   1.1
 11000 -11.4  11.5  185  10  5   5.6   3.1 | -11.8  10.8  185  11  6   2.1   1.2
 10500 -10.7  12.7  175   8  4   3.5   1.9 | -11.5  11.3  170  10  5   1.6   0.9
 10250 -10.4  13.3  170   7  4   2.9   1.6 | -11.4  11.5  165   9  5   1.6   0.9
 10000 -10.2  13.6  165   7  3   4.3   2.3 | -11.2  11.8  165   8  4   1.4   0.8
  9750  -9.8  14.4  155   6  3   4.0   2.2 | -11.2  11.8  155   7  3   0.6   0.3
  9500  -9.6  14.7  150   4  2   1.9   1.1 | -11.1  12.0  150   5  3   0.4   0.2
  9250  -9.5  14.9  140   3  2   2.0   1.1 | -11.1  12.0  145   4  2   0.7   0.4
  9000  -9.3  15.3  125   3  1   1.8   1.0 | -11.0  12.2  135   3  2   0.3   0.2
  8750  -9.3  15.3  105   2  1  -1.8  -1.0 | -11.1  12.0  125   2  1  -2.0  -1.1
  8500  -9.6  14.7  075   2  1  -4.6  -2.5 | -11.3  11.7  110   2  1  -3.1  -1.7
  8250  -9.9  14.2  045   2  1  -3.2  -1.8 | -11.5  11.3  070   1  1  -3.4  -1.8
  8000 -10.2  13.6  025   3  1  -6.3  -3.5 | -11.7  10.9  020   1  1  -1.2  -0.7
  7750 -10.7  12.7  020   3  2  -6.5  -3.6 | -11.6  11.1  010   2  1   2.1   1.1
  7500 -11.1  12.0  020   4  2  -3.0  -1.6 | -11.5  11.3  020   3  1   1.9   1.1
  7250 -11.2  11.8  025   4  2  -1.2  -0.6 | -11.3  11.7  035   3  2   3.4   1.8
  7000 -11.2  11.8  025   5  2   2.8   1.5 | -11.0  12.2  035   4  2   6.4   3.5
  6750 -10.9  12.4  030   4  2   6.0   3.3 | -10.4  13.3  035   4  2   8.2   4.5
  6500 -10.4  13.3  025   4  2   7.4   4.1 |  -9.8  14.4  035   4  2   9.0   4.9
  6250  -9.8  14.4  025   4  2   9.9   5.4 |  -9.1  15.6  030   5  2  10.0   5.5
  6000  -8.9  16.0  020   4  2  12.0   6.6 |  -8.3  17.1  030   5  2  11.0   6.0
  5750  -8.1  17.4  020   4  2   9.8   5.4 |  -7.5  18.5  025   5  2   9.7   5.3
  5500  -7.4  18.7  020   3  2  10.2   5.6 |  -6.9  19.6  020   4  2   8.9   4.9
________________________________________________________________________________

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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