880
FNUS71 KLWX 111517
FWSLWX

Spot Forecast for Mt. Joy Rx Burn...VDCR
National Weather Service Baltimore MD/Washington DC
1117 AM EDT Tue Mar 11 2025

Forecast is based on ignition time of 0900 EDT on March 12.
If conditions become unrepresentative...contact the National Weather
Service.

Please contact our office if you have questions
or concerns with this forecast.

.DISCUSSION...

...ELEVATED THREAT FOR THE SPREAD OF FIRES FROM LATE MORNING THROUGH
EARLY EVENING FOR NORTHWEST VIRGINIA...EASTERN WEST VIRGINIA...AND
NORTH-CENTRAL AND WESTERN MARYLAND...

High pressure over the southeastern states will promote very warm
and dry conditions this afternoon. Fire weather will be a concern
this afternoon across portions of the area, with conditions favorable
for the rapid spread of wildfires. Southerly flow will usher in plenty
of warm air with high temperatures expected to rise into the upper 60s
to mid 70s. RH values less than 25% combined with sunny skies, gusty
winds, and drying fuels will lead to elevated fire weather concerns
along and west of the Blue Ridge Mountains.

Winds diminish slightly on Wednesday, although low RH and dry
conditions will continue. One complicating factor with the Wednesday
forecast is a backdoor cold front moving in from the north. Where
this front sets up will make a big difference on temperatures and RH
across the area. It is possible some areas may have elevated fire
weather conditions again.

Looking to the rest of the week ahead, RH will gradually rise in
south to southwest flow ahead of an approaching frontal system late
week. Winds will be marginal Thursday before picking up again on
Friday. However, RH values going up should help to alleviate some of
the fire weather concerns later in the week. Further evaluation will
be needed if there are changes in the forecast in the coming days
however, because fuels will only get drier with warm temperatures
and no precipitation forecast.

Significant wetting rain remains likely late this weekend as a
strong frontal system pushes through the area. This system will also
bring a threat of thunderstorms and strong gradient winds,
especially on Sunday.

.WEDNESDAY...

Sky/weather.........Sunny (10-20 percent).
CWR.................0 percent.
Chance of thunder...0 percent.
Max temperature.....Around 67.
Min humidity........36 percent.
Wind (20 ft)........Becoming southwest 4 to 8 mph in
                    the afternoon, then shifting to the south
                    around 6 mph late in the afternoon.
Mixing height.......4300 ft AGL.
Transport winds.....Southwest 6 to 12 mph increasing to 18 to 21
                    mph late in the afternoon.
Smoke dispersal.....Poor (2300 knot-ft) early in the morning
                    increasing to excellent (78200 knot-ft) in the
                    afternoon.

TIME (EDT)      9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........25  11  7   4   2   2   2   12  8
Weather cov.....
Weather type....
Tstm cov........
CWR.............0   0   0   0   0   0   0   0   0
Chc of thdr (%).0   0   0   0   0   0   0   0   0
Temp............51  56  60  62  63  65  66  67  67
RH..............56  51  46  43  41  37  36  36  36
20 FT wind dir..S   SW  W   SW  SW  SW  S   S   S
20 FT wind spd..2   2   3   5   6   6   6   6   6
20 FT wind gust.7   8   10  13  14  15  15  16  16
Mix hgt (kft)...0.5 1.4 2.0 2.7 3.2 3.9 4.0 4.3 4.3
Transp wind dir.S   SW  SW  SW  SW  SW  SW  SW  SW
Transp wind spd.6   7   9   10  12  14  18  20  21
Vrate kt-ft/1K..2   8   16  24  32  46  64  73  78
Ventrate Cat....PR  PR  PR  PR  PR  FR  GD  GD  GD

.WEDNESDAY NIGHT...

Sky/weather.........Partly cloudy (30-40 percent).
CWR.................0 percent.
Chance of thunder...0 percent.
Min temperature.....Around 47.
Max humidity........68 percent.
Wind (20 ft)........South winds 4 to 8 mph early in the evening
                    becoming light.
Mixing height.......400 ft AGL.
Transport winds.....Southwest 7 to 14 mph shifting to the west
                    around 7 mph early in the morning.
Smoke dispersal.....Fair (23300 knot-ft) early in the evening
                    decreasing to poor (2300 knot-ft) late in the
                    night.

TIME (EDT)      6 PM         10 PM        2 AM
Sky (%).........23           38           35
Weather cov.....
Weather type....NONE         NONE         NONE
Tstm cov........
CWR.............0            0            0
Chc of thdr (%).0            0            0
Temp............65           57           52
RH..............38           49           56
20 FT wind......S 6G14       S 3G10       SW 2G8
Mix hgt (ft)....1700         400          400
Transport wind..S 16         S 12         SW 8
Vrate kt-ft/1K..23           4            3
Ventrate Cat....POOR         POOR         POOR

.THURSDAY...

Sky/weather.........Partly sunny (50-60 percent).
CWR.................10 percent.
Chance of thunder...0 percent.
Max temperature.....Around 69.
Min humidity........39 percent.
Wind (20 ft)........Light winds.
Mixing height.......5000 ft AGL.
Transport winds.....Southwest 6 to 12 mph shifting to the south
                    around 12 mph late in the afternoon.
Smoke dispersal.....Poor (1400 knot-ft) early in the morning
                    increasing to good (45800 knot-ft) in the
                    afternoon.

TIME (EDT)      6 AM         10 AM        2 PM
Sky (%).........47           59           50
Weather cov.....
Weather type....NONE         NONE         NONE
Tstm cov........
CWR.............0            0            10
Chc of thdr (%).0            0            0
Temp............48           56           67
RH..............65           62           42
20 FT wind......W 2G7        SW 2G7       S 3G10
Mix hgt (ft)....300          1300         4900
Transport wind..W 6          W 5          SW 9
Vrate kt-ft/1K..2            5            40
Ventrate Cat....POOR         POOR         POOR

$$
Forecaster...Witt
Requested by...Tyler Urgo
Type of request...PRESCRIBED
.TAG 2505881.0/LWX
.DELDT 03/11/25
.FormatterVersion 2.0.0
.EMAIL tyler.urgo@dcr.virginia.gov