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000
FNUS71 KRNK 211745
FWSRNK

Spot Forecast for Potts Mountain 8...USFS
National Weather Service Blacksburg VA
145 PM EDT Sun Apr 21 2024

Forecast is based on ignition time of 1500 EDT on April 21.
If conditions become unrepresentative, contact the National Weather
Service.

.DISCUSSION...

No rain is expected for the burn site, but a significant middle deck
of clouds remains and will remain for another several hours. Some
breaks should begin appearing by 5-6 PM this afternoon, which could
improve the current limited atmospheric mixing potential in the
evening hours. Patches of clouds will come and go during the overnight,
but by sunrise Monday morning, skies ought to be mostly clear.

Monday will be much drier, with almost no clouds and better mixing than
today. Prevailing winds will be out of the northwest 8 to 12 MPH,
though the site`s position on the east side of the ridge may provide
some minor shielding from that. The abundant sunshine on the slopes
may even encourage a light southeasterly wind at times.
Minimum RH will drop to around 30% Monday afternoon.

.REST OF TODAY...

Sky/weather.........Mostly cloudy (80-90 percent).
CWR (0.01 in).......10 percent.
Max temperature.....Around 48.
Min humidity........45 percent.
Wind (20 ft)........Northwest winds 9 to 11 mph.
Mixing height.......4700 ft AGL.
Mixing winds........Northwest 13 to 16 mph.
Smoke dispersal.....Excellent (68600 knot-ft).
LVORI...............1.
ADI.................44 to 50.
Haines Index........3 or very low potential for large plume
                    dominated fire growth.

TIME (EDT)      3PM 4PM 5PM
Sky (%).........92  89  73
Weather cov.....
Weather type....
Tstm cov........
CWR.............10  0   10
Temp............48  48  48
RH..............48  46  45
20 FT wind dir..NW  NW  NW
20 FT wind spd..9   9   11
20 FT wind gust.13  14  14
Mix hgt (kft)...4.5 4.6 4.7
Mixng wind dir..NW  NW  NW
Mixng wind spd..13  15  16
LVORI...........1   1   1
ADI.............50  44  48
Haines index....3   3   3
VRate mph-ft/1K.79  89  95

.TONIGHT...

Sky/weather.........Mostly cloudy (65-75 percent) then becoming
                    partly cloudy (30-40 percent) then becoming
                    mostly cloudy (55-65 percent) then becoming
                    partly cloudy (30-40 percent).
CWR (0.01 in).......10 percent.
Min temperature.....Around 32.
Max humidity........70 percent.
Wind (20 ft)........Northwest winds 8 to 12 mph.
Mixing height.......700 ft AGL.
Mixing winds........Northwest 17 to 25 mph decreasing to 6 to 12
                    mph after 3 am.
Smoke dispersal.....Excellent (88600 knot-ft) early in the evening
                    decreasing to poor (3800 knot-ft) late in the
                    night.
LVORI...............2.
ADI.................47 early in the evening decreasing to 4 late in
                    the night.
Haines Index........3 to 4 or very low to low potential for large
                    plume dominated fire growth.

TIME (EDT)      6 PM   8 PM   10 PM  MIDNGT 2 AM   4 AM
Sky (%).........68     19     47     65     49     29
Weather cov.....
Weather type....NONE   NONE   NONE   NONE   NONE   NONE
Tstm cov........
CWR.............10     0      0      0      0      0
Temp............47     42     40     38     36     34
RH..............45     53     56     59     60     62
20 ft wind......NW 12  NW 12  N 11   N 11   N 9    N 9
20 ft wind gust.14     17     16     16     14     13
Mix hgt (ft)....3900   2300   1500   1000   1000   800
Mixing wind......NW 17  NW 21  NW 23  N 25   N 21   NW 12
LVORI...........1      2      2      2      2      3
ADI.............47     28     15     17     19     8
Haines index....3      3      3      3      4      4
VRate mph-ft/1K.102    38     24     29     26     8

.MONDAY...

Sky/weather.........Sunny (0-10 percent).
CWR (0.01 in).......0 percent.
Max temperature.....Around 57.
Min humidity........32 percent.
Wind (20 ft)........Northwest winds 5 to 8 mph.
Mixing height.......5600 ft AGL.
Mixing winds........Northwest 6 to 12 mph.
Smoke dispersal.....Poor (4700 knot-ft) early in the morning
                    increasing to good (58800 knot-ft) in the
                    afternoon.
LVORI...............2.
ADI.................3 early in the morning increasing to 74 in the
                    afternoon.
Haines Index........4 to 5 or low to moderate potential for large
                    plume dominated fire growth.

TIME (EDT)      6 AM   8 AM   10 AM  NOON   2 PM   4 PM
Sky (%).........12     2      3      1      4      4
Weather cov.....
Weather type....NONE   NONE   NONE   NONE   NONE   NONE
Tstm cov........
CWR.............0      0      0      0      0      0
Temp............33     34     39     43     48     51
RH..............66     65     53     43     35     32
20 ft wind......NW 8   N 8    N 6    N 5    NW 6   NW 8
20 ft wind gust.11     11     10     10     10     11
Mix hgt (ft)....500    1200   2900   4300   5600   5600
Mixing wind......NW 7   N 12   NW 6   NW 5   NW 8   NW 10
LVORI...........3      3      2      2      1      1
ADI.............3      18     26     25     56     69
Haines index....4      4      4      4      5      5
VRate mph-ft/1K.5      16     22     22     51     63

$$
Forecaster...Joyner
Requested by...Robbie Claytor
Type of request...PRESCRIBED
.TAG 2411421.3/RNK
.DELDT 04/21/24
.FormatterVersion 2.0.0
.EMAIL robert.claytor@usda.gov