Area Forecast Discussion
Issued by NWS Sterling, VA
FXUS61 KLWX 290757
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
357 AM EDT SUN MAY 29 2016
Tropical Storm Bonnie has moved onto the South Carolina coast.
This will track slowly northeastward for the remainder of the
holiday weekend. An upper level trough will track north across
northern New England Monday. High pressure will build into the
area for midweek. A cold front will push through the region Friday.
.NEAR TERM /TODAY/...
TS Bonnie has moved onto the SC coast. Its moisture will be
tracking north into the CWA this afternoon bringing rain to the
region...especially east of the Blue Ridge. That area is outlooked
in slight risk of excessive rainfall. Flash flood guidance east of
the mountains is 2-2.5 inches in 3-6 hours. Current forecast is
for about 1.5 inches east of the mountains through Monday night
with the heaviest rainfall expected tonight through Monday
morning. Given these facts do not feel the need to put up any sort
of flood watch. DC/Baltimore urban areas are always points of
special interest in potential heavy rain situations. Later shifts
will continue to monitor.
Given increasing cloud cover and rainfall temperatures will not be
quite as warm as in previous days. Highs in the lower 80s.
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
Cloudy and rainy tonight as mentioned in the previous section.
Lows in the mid 60s.
An upper level trough presently over MN will be tracking east
tonight...moving across ME and into Atlantic Canada Monday. This
will force the moisture from Bonnie more onto the Delmarva...
leaving the highest POPs along the Bay Monday morning. Some
clearing will be possible west of the Blue Ridge during the
afternoon...but much of the area will experience a cloudy Memorial
Day. Highs around 80.
Bonnie will likely be weakening Monday night and Tuesday...
although the eastern part of the area may still be partly to
mostly cloudy Monday night. Mostly sunny across the region
Tuesday. Highs in the mid 80s then lower to mid 60s Tueday night.
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Weather for the second half of the work week depends on the location
of Bonnie (or her remnants). She is expected to crawl along the
Carolina coast into or perhaps through Thursday. Upper-level ridging
over the eastern Great Lakes should allow an onshore flow and
promote scattered diurnal convective thunderstorms Wednesday.
An upper level trough pushes east across the great lakes Thursday.
The associated cold front enter the LWX CWA Thursday night. This
front looks to stall and both allow continued onshore flow and bring
an active weather period into next week. Temperatures at or just
below normal through the extended.
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
Beautiful skies outside at the moment but clouds will overspread
the Mid Atlantic this morning. Showers will move into CHO area
this afternoon with ceilings dropping into MVFR range tonight.
Moderate to heavy rainfall expected tonight east of the Blue Ridge
with ceilings dropping to IFR levels late tonight and continuing
Monday morning. Improvement expected Monday afternoon.
Onshore flow Wednesday with diurnal scattered thunderstorms. Cold
front approaches from the west Thursday with continued onshore flow
and possible low ceilings. Cold front stalls over the area into next
Winds expected to remain below SCA values today through Memorial
Day but rain will be moving into the region this afternoon...
possibly heavy tonight and Monday. No problems on the waters
Monday Night or Tuesday.
Onshore flow likely below SCA levels Wednesday and Thursday ahead of
a cold front and as Bonnie lingers along the NC coast. Thunderstorms
possible in this time.