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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 231350
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
950 AM EDT Sat Mar 23 2019

.SYNOPSIS...
High pressure will build across the area through Sunday. The
next low pressure system will pass near the area on Monday, then
Canadian high pressure will build in for the middle of next
week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Strong low pressure is moving into the Canadian Maritimes this
morning. Tight cyclonic flow remains across the area through,
meaning winds are still quite gusty. While there are several
inversion between the surface and 500 mb, winds within this
layer 40-45 kt. Most of the strongest winds aloft are failing
to mix to the surface, but some sporadic gusts up to 40 mph
will be possible for a couple more hours (a few stronger gusts
may persist on the ridge tops).

It will remain breezy into the afternoon given the pressure
gradient, though wind speeds should lessen some. The only
clouds remaining are across the Appalachian ridges, and even
these should dissipate as high pressure builds. High
temperatures are expected to range from the mid 40s to mid 50s.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
The surface high will move overhead by tonight. With clear
skies, temperatures should drop back into the 20s and 30s. The
high will move off the southeast coast on Sunday. Southwesterly
flow will help temperatures rebound into the 50s and 60s. Mid
and high level clouds will begin to increase during the
afternoon.

The next shortwave trough and associated surface low will
approach from the west and affect the area Sunday night into
Monday night. With little interaction between this wave and the
northern stream, it looks like the low will take an easterly
track nearly over the area. Eventually, the Canadian cold front
will overtake it from the north, but likely not until most of
the precipitation exits.

A few showers will be possible as ascent increases Sunday
night, although temperatures should be above freezing
everywhere. The best chance of rain will be Monday as the low
crosses, although amounts will be light and precipitation may
tend to be spotty at times given the system`s continental
origins. If current trends for the low track hold, temperatures
may ultimately be held in the 40s and 50s for a larger portion
of the area (versus 60s). Some wet snow flakes can`t totally be
ruled out Monday night as the system pulls away, although am
currently thinking the best chance for this to happen would be
over the higher elevations. Lows AOB freezing are forecast for
much of the area, but this will likely occur well after
precipitation ends for most.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
After Monday, much of next week will feature quiescent weather
dominated by surface high pressure. Temperatures will start cool and
below normal but rebound to near or above normal by week`s end.

High pressure will build into the northeastern US on Tuesday, move
to the coastal plain by Wednesday and offshore on Thursday. This
will lead to mostly sunny/clear skies and dry weather through the
period. The coolest temperatures are expected to be Tuesday and
Tuesday night with highs in the 40s to near 50F and lows in the 20s
to around 30F. Temperatures will moderate through Wednesday and
Thursday with highs Wednesday rebounding through the 50s, and
reaching the upper 50s to low 60s by Thursday.

A low pressure system will then be moving through the central US and
towards the Great Lakes by Friday. Southerly flow will increase out
ahead of this system across the region, but dry weather is expected
to continue. Highs should reach well into the 60s Friday.

&&

.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
The main aviation concern for the TAF period will be continued
gusty NW winds. Gusts should generally range from 25-30 kt, but
some rogue gusts into the upper 30s could occur through mid-
morning. Winds should subside quickly after sunset this evening
as high pressure builds in.

VFR conditions will persist through Sunday and likely through
much of Sunday night, although some light rain showers may
arrive ahead of the next system. This low will cross the area on
Monday, with rain likely affecting the area and the potential
for MVFR conditions. The chance for precipitation will dwindle
by Monday night.

VFR under building high pressure Tuesday and Wednesday.

&&

.MARINE...
Strong, gusty winds continue on the waters this morning. Have
replaced the Gale Warning with a solid Small Craft Advisory for
much of the waters. Between Drum Point-Smith Point, including
Tangier Sound and the mouth of the Potomac, the Gale Warning set
to expire at 10 am anyways. Small Craft Advisory conditions
will continue for the rest of the day. Observations generally
support that plan, although there still are some borderline
gale gusts. Winds within the mixed layer do gradually decline.

Wind should subside tonight as high pressure builds in, but it
may not be until an hour or two after sunset. Have adjusted the
end time of the Small Craft Advisory later for the bay between
Drum Point- Smith Point, including Tangier Sound and the mouth
of the Potomac. May need to delay the ending of the SCA
elsewhere too. Will make that decision later today.

Southwest winds around 10-15 kt develop Sunday and Sunday night as
the high moves offshore. Low pressure will cross over the
waters on Monday. Given the current track, winds may remain
below criteria for most of the day. A strong cold front will
push south during the afternoon and evening, with northerly
winds likely resulting in Small Craft Advisory conditions in
its wake.

SCA conditions possible Tuesday following frontal passage, with
winds lessening by Tuesday night and Wednesday as high pressure
builds in.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 8 PM EDT this evening for
     ANZ530>533-535-536-538>542.
     Small Craft Advisory until 11 PM EDT this evening for ANZ534-
     537-543.
     Gale Warning until 10 AM EDT this morning for ANZ534-537-543.

&&

$$
SYNOPSIS...ADS
NEAR TERM...ADS/HTS
SHORT TERM...ADS
LONG TERM...MM
AVIATION...ADS/MM
MARINE...ADS/MM/HTS