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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPHI 260239
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
939 PM EST Sat Jan 25 2020

.SYNOPSIS...
Intensifying low pressure will move northeast of the area this
evening into Sunday and a cold front will move through our area
this evening. A weak trough south of the main low will pass near
the region on Monday. High pressure will then slowly build across
the eastern half of the US through the remainder of the workweek
before another area of low pressure approaches next weekend.

&&

.NEAR TERM /TONIGHT/...

The surface low which passed over the area earlier, is now over
southern New England and will continue to move northeastward
through the overnight period. Behind the low colder and drier
westerly flow has overspread the area and this is expected to
persist through the night. Most of the area will see limited
cloud cover, although the northwestern half of the area will
likely see some mid lvl clouds rotate in later in the night as
the mid-lvl low approaches from the west. Lows are expected to
generally be in the low to mid 30s.

&&

.SHORT TERM /SUNDAY/...

The mid level low is forecast to move across the Adirondacks,
northern New England and southern Quebec on Sunday. The feature
is expected to pull a couple weak short wave troughs over our
region on Sunday. As a result, we should see an increase in
stratocumulus during the daylight hours. Highs should favor the
40s with a west wind around 10 mph.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
Summary: It will be a relatively uneventful end of January as a
generally dry and seasonable northwest flow aloft prevails for
the bulk of the work-week with only a few low-amplitude and
moisture-starved disturbances passing through. A stronger and
more organized storm system may approach the area next weekend,
but details are lacking at this point.

Details:

Monday/Tuesday: The secondary low which passed through the area
today will ultimately strengthen and merge with the primary
Great Lakes Low by Sunday night (over New Brunswick). A back-
side mid-lvl shortwave will slide through the area on Monday
with a weak sfc.trough extending from the larger low to our
north. Given weak forcing and limited moisture do not expect
much precipitation outside of possibly some snow
showers/flurries over the far north, although there could be
locally thick stratocumulus at times (particularly over the
northern half of the area in the afternoon). Tuesday will be
largely uneventful although a dry cold front does look to push
in late in the day. Temperatures will generally be about 5
degrees above normal on Monday, and will cool slightly to a
couple degrees above climo on Tuesday.

Wednesday-Friday. Quiet and dry as high pressure initially
centered over central Ontario builds SE over the region.
Temperatures will be seasonable through the period with highs
generally in the upper 30s to low 40s Wed/Thurs. The High may
move offshore by Friday with some return flow developing so
Friday could be a bit warmer.

Saturday and beyond. A storm system looks to approach (possibly
taking the form of a coastal low) next weekend but details
regarding the track and associated precipitation and thermal
fields are unknown at this time. Left PoPs in the Chc.Range due
to timing uncertainties.

&&

.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Overnight...VFR. West winds around 5 to 10 knots. High confidence.

Sunday...VFR. West winds increasing around 10 knots with gusts near
20 knots through the afternoon. High confidence.

Outlook...

Sunday night-Tuesday...Mainly VFR, though cigs could
occasionally approach MVFR at times due to stratocumulus. Winds
remain west to northwest and may gust up to 20 knots at times
during the daytime hours. Moderate confidence.

Wednesday/Thursday...Mainly VFR with NW winds 5-10 knots on Wed,
and N winds 5 kts or less on Thursday..

&&

.MARINE...
A Small Craft Advisory remains in effect for the coastal waters
through Sunday afternoon as decaying low pressure over southern
Quebec slowly drifts east. Wind gusts will stay close to our just
below 25 kts Sunday night with the SCA possibly needing to be
extended through the night.

Outlook...

Monday... Winds and waves will slowly relax through the day Monday
as the pressure gradient weakens.

Tuesday through Thursday... Winds and waves will remain below
advisory levels through the period.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory until 6 PM EST Sunday for ANZ450>455.

&&

$$
Synopsis...Carr
Near Term...Carr
Short Term...Iovino
Long Term...Carr
Aviation...Carr/Iovino/Meola
Marine...Haines