Area Forecast Discussion
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FXUS61 KLWX 191853
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
253 PM EDT Wed Apr 19 2017
.SYNOPSIS...High pressure off of Atlantic Canada will move
further away from the coast tonight and Thursday. A lee-side
trof will setup across the area tomorrow. A cold front will
cross the area Friday afternoon. Weak high pressure builds over
the area Friday night before another low pressure impacts the
area Saturday night and Sunday.
.NEAR TERM /THROUGH THURSDAY/...Light rain over ncntrl MD will
taper off later today with patchy drizzle and areas of fog
developing late tonight as mid-levels dry out and moist air
remains in place near the sfc. Low clouds/fog dissipate by mid-
morning Thu with risk of showers and t-storms as lee-side trof
sets up and provides lift and instability builds as temps rise
through the 70s to perhaps 80F.
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...Shra/tsra
activity will wane with loss of heating Thu evening, but
approaching cdfnt from the west could bring another round of
late night and early morning showers Thu night and Fri. Still
warm on Fri with sufficient moisture and instability Fri
afternoon for another round of showers/t-storms mainly across
the southern half of the fcst area. The 12Z GFS wants to push
the front all the way into North Carolina, but the latest Euro
keeps the front across srn VA keeping the risk of showers across
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
An area of low pressure will take shape over the south-central CONUS
Saturday morning, then slowly push east just south of the area
through the second half of the weekend. Models are in general
agreement with this setup, which should result in a beneficial
soaking rain across much of the area.
A cool area of high pressure will persist to the north following the
weekend system which should keep temperatures near to below normal
for this time of year during the first half of next week. Periods of
clouds or sprinkles will be possible in onshore flow as well.
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...MVFR/IFR cigs
developing tonight with areas of fog with 1-3SM vsbys. Sct-nmrs
showers and t-storms Thu afternoon potentially affecting all
TAFs sites. Cdfnt moves through Fri afternoon with risk of
showers/t-storms again on Fri.
Sub-VFR likely over the weekend with rain. Winds will
generally be out of the northeast around 10 knots or so.
.MARINE...Canadian HRDPS suggests winds will increase across
the waters tonight, but other reliable guidance such as the GEFS
and SREF indicate winds will remain steady and perhaps even
diminish tonight. Solid SCA not likely until Sun afternoon when
low pressure moves offshore.
Northeasterly winds of 10 to 15 knots are expected across the
waters over the weekend as low pressure passes to the south.
Gusts would exceed 20 knots for a time especially Saturday as
the pressure gradient tightens between low pressure developing
to the southwest and high pressure developing to the northeast.
.TIDES/COASTAL FLOODING...Minor coastal flooding expected at
Straits Point over the next two high tide cycles tonight and Thu
morning as onshore flow persists. Cdfnt will clear the area Fri
afternoon with positive anomalies dropping.
MD...Coastal Flood Advisory from 7 PM this evening to 11 AM EDT
Thursday for MDZ017.