Area Forecast Discussion
Issued by NWS Mt. Holly, NJ
FXUS61 KPHI 280959
Area Forecast Discussion
National Weather Service Mount Holly NJ
559 AM EDT Tue Mar 28 2017
Weak low pressure will move across the Middle Atlantic region today
and then offshore tonight. Large high pressure will build across the
area Wednesday and then move east of the area by Friday morning. A
low and its associated fronts will push across our region Friday and
remain into Saturday. More high pressure will be over the area
Sunday and into Monday. Another disturbance may affect the area Next
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
6 AM ESTF: CHILLY NNJ and a struggle to reach our fcst max
temps. Groups/bands of heavy showers and isolated tstms should
continue in NJ today and develop into the Delmarva and se PA
later this morning. Torrents of rain in stronger cells with
possibly pea sized hail as reported from Lawrenceville around
305AM this morning in a cell VIL of ~34 and well monitored by
our DIX MESH.
DFA (NPW) cancelled Ocean and Monmouth where rains mixed out the
Today...Murky again. Mostly cloudy. Fog and scattered heavy showers
and isolated tstms, especially north of the boundary this morning.
Possibly a stronger tstm on the Delmarva this aftn where best
MLCape of less than 800J. Weak speed shear so svr not expected.
PWAT 1.25 so brief torrents of rain possible in any shower.
Please follow later PHI discussions and those of SPC regarding
FCST basis: 50 50 blended 00z/28 GFS/NAM MOS.Temps were modified
downward using the 2m temps from HRRR and NAM. Note..thats max
temps in the mid to upper 40s Sussex County, Monmouth and Ocean
counties. Going to be difficult for PHL to reach 60. More
likely upper 50s there.
So the temperature forecast remains a concern with the
placement of the eastward- extending warm front again a
complicating factor. Errors in these values are likely given
timing of the rain cooling factor and where skies may thin to
allow a little sun.
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
Any remaining showers end from west to east with a slightly
faster modeled end to the rain than 24 hours ago.
There could be some patchy fog, especially early at night in
the still moist boundary layer with a light north wind
increasing a bit late at night and trending northwest.
FCST Basis was a 50 50 blend of the 00z/28 GFS/NAM MOS.
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
A rather steady progression of disturbances in the extended period
with a 2 day (or so) return period. Fair weather is expected for
much of Wednesday and Thursday as high pressure across Canada ridges
southward across the area. Temperatures will be close to normal with
highs in the mid/upper 50s south and low/mid 50s north. Lows will be
in the mid/upper 30s north and low 40s south. It will be dry and
breezy Wednesday, but with wet ground conditions, fire weather
hazards will probably not be a big concern.
The first of two disturbances in the long term will affect much of
the area for much of Friday and Saturday. Low pressure will move up
the Ohio Valley Friday and then off the VA Tidewater area Saturday.
Our region will remain on the cooler nrly part of the system.
Occasional showers should occur much of the time. Depending on what
computer model, the rains could begin Thu night. Temperatures should
remain near or a little below normal thru the period. A couple
snowflakes across the highest elevations of the southern Poconos are
Fair weather returns over the region for Sunday and persist into
Monday as high pressure to the north ridges across the area.
Temperatures will be a little above normal with upper 50s to low 60s
for highs in most areas. Another disturbance may approach for Tue
with the latest EC model having a soaker system across the area and
the GFS much slower with the low and a fair weather day for Tue. We
just have chc pops for now.
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.
Today...variable conditions with general deterioration to IFR
conds in st/fog by 12z in the light northeast flow. The southerly
winds TAFS of MIV and ACY could remain VFR much of the day except
lower in showers. Then considerable deterioration ACY and MIV
late today when the wind turns decidedly northeast.
Bands of showers and isolated tstms, some with brief heavy rain.
light wind, mostly east or northeast at the TAF locations
except southeast to south at KMIV and KACY at least this
Tonight...MVFR/IFR conditions possible in showers and fog early...
becoming VFR late. Light north winds will become north to northwest
overnight around 10 knots.
wed/thu...VFR expected. Gusty north winds Wed.
fri/sat...lower cigs/vsbys expected. Showers.
Dense Fog Advisory continues for the New Jersey coastal waters
north of Little Egg. Areas south may also develop dense fog
this morning, but it is less certain at this time.
Winds/seas will be under advisory criteria through Tonight.
Scattered showers/isolated thunderstorms through today, with
showers ending this evening.
wed night/thu morning...low end sca near the nj coastal waters.
thu afternoon thru fri...sub-sca expected. Showers fri. fri
night thru sat...sca possible. showers.
KNEL appears to be reading 10F too warm the past several days.
MARINE...Dense Fog Advisory until 10 AM EDT this morning for ANZ450-451.
Near Term...Drag 6a