-- Discussion containing changed information from previous version are highlighted. --
046
FXUS61 KLWX 141850
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
250 PM EDT Fri Jun 14 2024

.SYNOPSIS...
-- Changed Discussion --
A cold front will cross the Mid-Atlantic tonight. High pressure
builds in this weekend. A warm front lifts across the region Monday
as high pressure shifts off the East Coast through next week. A
prolonged period of hot temperatures take hold of the region next
week.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
As of 2 PM prefrontal showers over the Alleghenies are pushing east
into the Shenandoah Valley. Large dew point depressions to start off
likely means most of this is virga, though stronger updrafts are
being noted on radar, with some moderate rain in the Waynesboro to
Harrisonburg area. This light precip/cloud cover moves east of the
Blue Ridge through late afternoon.

Temperatures have reached the upper 80s to low 90s east of the Blue
Ridge, and low to mid 80s west. The bay breeze has pushed onshore
along the Western Shore, with 70F dew points observed behind it.
Deeper mixing just to the west of the bay breeze toward the Piedmont
has dropped dew points to the upper 50s to low 60s.

The broad cloud cover and westerly/downslope flow across most of the
area west of the Blue Ridge is likely to prevent severe storms from
developing. The main area to watch is northern to northeast MD where
the bay breeze boundary, and higher moisture/instability are
currently present. The frontal boundary across western PA to central
OH will slide south this evening, generating isolated to scattered
showers and storms along the way. SPC has extended the Slight Risk
across the I-70/I-68 corridor, with Marginal Risk for most of the
rest of the CWA. However, as previously mentioned the best chance
for severe storms looks limited to north/northeast MD, maybe down to
the far northern DC suburbs.

Trailing showers and a few storms linger through around midnight,
then conditions dry out as the front pushes south of the area. Skies
clear out late as temperatures settle in the upper 50s out west to
mid 60s along I-95.
-- End Changed Discussion --

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
-- Changed Discussion --
Large surface high over southern ON/central Great Lakes on Saturday
quickly shifts east over the Northeast, then off the southern New
England coast Sunday night. Dry and seasonal conditions expected.
Afternoon highs reach the low to mid 80s each day, with mid to upper
70s in the mountains. Seasonal overnight lows in the mid 50s to low
60s Saturday night. A warm front lifts north through the area Sunday
night, bringing in milder temperatures.
-- End Changed Discussion --

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
Strong upper level ridging will dominate the weather pattern
throughout the long term period, with dry conditions and well above
normal temperatures expected. At the surface, high pressure builds
over the Mid-Atlantic and lingers through the week. There remains
uncertainty amongst global guidance with regards to the exact
placement of the upper level ridge, with the ECMWF having the driest
solution. On the contrary, the GFS and Canadian show increased
moisture aloft as the ridge pivots overhead leading to a chance of
showers and thunderstorms in the afternoon. For the forecast, PoPs
are trending low with primarily dry conditions expected for our area
but a stray shower or sprinkle cannot be ruled out in the western
portions of the area.

The main weather hazard for next week will be above normal
temperatures. High temperatures east of the Alleghenies will rise
well into the 90s each day with increased humidity leading to
warming heat indices and record high temperatures are possible. Heat
indices in the upper 90s are expected with lower to mid 100`s
possible. As the ridge axis pivots over the area, southerly winds
will shift to southeasterly, providing a slight cool down with high
temperatures in the mid 90s expected. That being said, relative
humidities will increase with southeasterly flow which will possibly
lead to continued heat index concerns. Heat advisories or heat
watches may be needed at some point during the long term.
-- End Changed Discussion --

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
A cold front will cross the area this evening, bringing scattered
showers and thunderstorms to most terminals between 21Z to 01Z. As
of now, activity looks to remain scattered, so no TEMPO groups have
been added to the 18Z TAFs. Still, any storm that does move over a
terminal could produce brief restrictions, in addition to gusty
winds. A few showers could linger into the evening.

Behind the front, VFR conditions are expected tonight through the
weekend. Northerly winds Saturday weaken Saturday night into Sunday,
eventually becoming east to southeast.

VFR conditions are expected both Monday and Tuesday with hot and dry
conditions expected at all terminals. Winds remain light, blowing 5-
10 knots, out of the south.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
A Small Craft Advisory is in effect for the main channel of the
Chesapeake Bay between Sandy Point MD and Smith Point VA. Southerly
channeling combined with the afternoon bay breeze should be
sufficient for a period of gusts around 20 knots. A brief period of
NW 15-20 knot gusts is possible in the wake of a cold front this
evening, with gustier winds possible in shower or thunderstorm
activity (may require Special Marine Warnings).

Northerly channeling behind the cold front will produce SCA
conditions over most of the waters of the Chesapeake Bay and Lower
Tidal Potomac. Another Small Craft Advisory is in effect from early
Saturday morning through Saturday afternoon.

After that, winds diminish below SCA conditions through Sunday night
as high pressure shifts offshore of the New England coast. Local
winds go from north to east, then southeast Sunday afternoon.

Southerly channeling will lead to possible SCA conditions both
Monday and Tuesday. Outside of gusty winds, hot and dry conditions
are expected to start out the week.
-- End Changed Discussion --

&&

.CLIMATE...
-- Changed Discussion --
High temperatures for next week. Below is a list of record high
temperatures for June 17th, 18th, 19th, and the 20th and the
year the record was set, and the current forecast high
temperatures for those days. Daily temperature records are
currently only maintained at DCA, IAD, BWI, and MRB. Others are
shown for reference.

                                     Monday Jun 17th
Climate Site                  Record High     Forecast High
Washington-National (DCA)     99F (2022)          95F
Washington-Dulles (IAD)       96F (2022)          95F
Baltimore (BWI)               96F (2022+)         93F
Martinsburg (MRB)             98F (1939+)         93F
Charlottesville (CHO)         97F (2022)          94F
Annapolis (NAK)               96F (1939)          88F
Hagerstown (HGR)              96F (1952)          94F

                                     Tuesday Jun 18th
Climate Site                  Record High     Forecast High
Washington-National (DCA)     97F (1944)          97F
Washington-Dulles (IAD)       94F (2018+)         97F
Baltimore (BWI)               97F (1957+)         95F
Martinsburg (MRB)             99F (1943)          95F
Charlottesville (CHO)         96F (2014+)         96F
Annapolis (NAK)               96F (1957)          90F
Hagerstown (HGR)              95F (1957)          97F

                                    Wednesday Jun 19th
Climate Site                  Record High     Forecast High
Washington-National (DCA)     99F (1994)          94F
Washington-Dulles (IAD)       98F (1994)          95F
Baltimore (BWI)               99F (1994)          92F
Martinsburg (MRB)             96F (1994+)         93F
Charlottesville (CHO)         97F (2018)          94F
Annapolis (NAK)               96F (1993)          87F
Hagerstown (HGR)              97F (1994)          95F

                                    Thursday Jun 20th
Climate Site                  Record High     Forecast High
Washington-National (DCA)     99F (1931)          94F
Washington-Dulles (IAD)       97F (1964)          95F
Baltimore (BWI)              100F (1931)          92F
Martinsburg (MRB)             98F (1931)          93F
Charlottesville (CHO)         98F (1933)          93F
Annapolis (NAK)               98F (1988)          88F
Hagerstown (HGR)              98F (1931)          94F

+ indicates that value has been reached on multiple years, with
the year displayed being the most recent.
-- End Changed Discussion --

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Small Craft Advisory from 4 AM to 11 AM EDT Saturday for
     ANZ530>532-539>541.
     Small Craft Advisory until 9 PM EDT this evening for
     ANZ532>534-537-542.
     Small Craft Advisory from 4 AM to 3 PM EDT Saturday for ANZ533-
     534-537-542-543.
-- End Changed Discussion --

&&

$$

SYNOPSIS...DHOF/KRR
NEAR TERM...KRR
SHORT TERM...KRR
LONG TERM...AVS
AVIATION...KRR/AVS
MARINE...KRR/AVS
CLIMATE...LWX