Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Baltimore Maryland/Washington District of Columbia
346 am EDT Sat Aug 1 2015
a weakening cold front will cross the region today. High pressure
will rebuild overhead Sunday before moving off the coast early
next week. Another cold front will approach from the northwest
Monday and then it will stall out nearby for Tuesday and
Wednesday. Low pressure may ride along the boundary...passing
through our area Thursday and the boundary will shift to the south
late in the week.
Near term /through tonight/...
weak cold front located over the Midwest will push through the
region later today. The front will bring a weak wind shift to the
west-northwest around midday but no precipitation is expected. Afternoon
high temperatures are expected to top out in the upper 70s to low
80s west of the Blue Ridge...middle to upper 80s east of the Blue
Ridge...except near 90 over the Baltimore and Washington District of Columbia metropolitan
areas. Overnight lows will dip back into the 60s...except low 70s
in the metropolitan areas. Some patchy fog could develop overnight.
Short term /Sunday through Sunday night/...
high pressure will build over the region on Sunday. Afternoon
high temperatures will likely reach into the upper 80s to the
lower 90s...warmest over the District of Columbia/Baltimore metropolitan areas.
High pressure will weaken over the area Sunday night...but it
should continue to bring dry conditions to the area. Min temperatures
will range from the 50s and 60s in the Potomac Highlands to the
lower and middle 70s in downtown Washington/Baltimore.
Long term /Monday through Friday/...
a weak cold front will pass through the area Monday afternoon and
evening. However...it will actually turn out hotter Monday due to
plenty of sunshine and a downsloping westerly component to the
surface flow. Maximum temperatures will be in the lower to middle 90s across
most areas. Dewpoints should remain in the 50s and lower 60s for
most areas...keeping relative humidity down which should allow for
heat indices to be near the air temperatures. An isolated shower
or thunderstorm cannot be ruled out...but most areas will turn out
Weak high pressure will build overhead Monday night...bringing dry
An upper-level low will continue to spin near the Hudson Bay
Tuesday through Friday while an upper-level ridge remains centered
across the south-central Continental U.S. Across Florida into the Atlantic
Ocean. A zonal flow is expected overhead during this time. A
nearly stationary boundary will separate the two airmasses between
cool conditions across the northeastern Continental U.S. And hot and humid
conditions across the southeastern Continental U.S.. there is still some
uncertainty as to where exactly this boundary will setup...but
latest guidance keeps it near the Mason-Dixon line through the
middle portion of next week before the boundary possibly sliding
south late in the week.
If the boundary remains to our north...then unsettled conditions
are possible due to the warm and humid conditions overhead along
with disturbances in the zonal flow aloft. However...if the
boundary is farther south...then cool and less humid conditions
will keep unsettled weather to our south. As of now...the forecast
leans toward the first scenario which is in agreement with most of
the guidance. However...there is still uncertainty with the model
forecasts during this time frame. A stronger upper-level
disturbance/surface low may enhance the threat for convection
Wednesday night through Thursday if the boundary is farther north
near the Mason-Dixon line.
Aviation /07z Saturday through Wednesday/...
VFR conditions expected today through Sunday. Some patchy fog
could develop in spots overnight into early Sunday but confidence
in direct impact to any terminal is low and mention will be kept
out of the tafs at this time.
High pressure will allow for dry conditions Sunday night. A weak
cold front may trigger an isolated thunderstorm Monday...but most
areas will be dry. An isolated shower/thunderstorm is possible
Tuesday...but again most areas will end up dry. There may be a
better chance for showers and thunderstorms during the middle
portion of next week.
winds will likely remain below Small Craft Advisory through Sunday. A weak cold
front will cross the waters by early this afternoon but wind gusts
should remain below Small Craft Advisory criteria.
High pressure will remain near the waters Sunday night. A weak
cold front will pass through the waters late Monday into Monday
night. Southwest winds ahead of the boundary may gust around Small Craft Advisory
criteria ahead of the front Monday afternoon and evening. Westerly
winds behind the boundary may gust near Small Craft Advisory criteria overnight
A stationary boundary will setup near the waters during the middle
portion of next week...and unsettled conditions are possible
during this time.
full moon will cause astronomically high
tides today. While tides will be slightly above normal...am not
expecting any flooding.
District of Columbia...none.