Area Forecast Discussion
Issued by NWS Mt. Holly, NJ-- Remove Highlighting --
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FXUS61 KPHI 260721
Area Forecast Discussion
National Weather Service Mount Holly NJ
321 AM EDT Sun Mar 26 2017
Canadian high pressure will build into our area today. Low
pressure moving from the Mississippi Valley into the Great Lakes
will allow a warm front to move northward through the region on
Monday, followed by a cold front Tuesday night. Canadian high
pressure will build into our area Wednesday through Friday. By
next weekend, low pressure moving into the Ohio Valley may send
a warm front toward the region.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
High pressure across Quebec/Maine will move offshore today while
weak low pressure slowly moves to near Chicago by evening. A
steady onshore flow will continue across our area thru the day.
This will promote an abundance of low clouds and fog along with
some light rain and drizzle at times. Pops will be greatest
across the northern areas where we have hi chc pops and the pops
taper off s/e to slgt chc across srn DE. Unlike Saturday,
temperatures will be below normal, with highs only in the 40s in
most areas, and a few low 50s over Delmarva.
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
The overall pattern will not change much tonight with high
pressure north/east and weak low pressure moving closer across
the Great Lakes. The onshore flow will continue and the chances
for more measurable rains will increase tonight. The best
chances will again be across the southern Poconos, Lehigh valley
and north NJ where we will have categorical pops. The pops
decrease back to likely over the Del Valley and cntrl NJ and the
chc pops over south NJ and srn DE. Patchy fog and drizzle will
occur between the bouts of rain. Overall qpf will not be that
great, a few hundredths across the south and up to 1/4 inch up
.LONG TERM /MONDAY THROUGH SATURDAY/...
Will be updated shortly.
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.
Not a particularly great day for flying across the Delaware
Valley and surrounding areas with a prolonged onshore flow and
low clouds expected today and tonight. Cigs are lowering across
the area early this morning from N to S over the region behind
the cold front which crossed the area earlier. Ocnl drizzle and
fog will occur as the lower level moisture thickens up. Overall
confid in tafs as to when precip will occur is limited. NE to E
winds mostly 10 to 15 kts today and tonight.
We will keep the SCA flags as they are on the waters and just
raise the next segment with the 330 am issuance, instead of
waiting until 6 a.m. The onshore flow will continue today and a
gradual building of seas will continue. Scattered showers and
patchy fog expected.
In the wake of a backdoor frontal passage, a 36 hour period of
onshore flow is expected through Monday morning, with easterly
wind gusts up to 25 MPH at times. Astronomical tides are also
increasing, coincident with the New Moon this Monday, March 27.
The ESTOFS remains most aggressive out of the guidance suite,
with near minor flooding for the sunrise Monday high tide along
the DE and NJ oceanfront, and it has has outperformed the other
guidance recently. Both the NOS and ETSS are more conservative.
The wind will also be trending more parallel (southerly) to the
shore by sunrise Monday, so there remains uncertainty with
regard to water levels reaching the minor flooding threshold.
MARINE...Small Craft Advisory until 8 AM EDT Monday for ANZ452-453.
Small Craft Advisory until 8 AM EDT Monday for ANZ450-451.