Area forecast discussion 
National Weather Service Mount Holly New Jersey 
912 PM EST Sat Dec 3 2016 


Synopsis... 
high pressure will build across the area on Sunday. A disturbance 
will affect the area on Sunday night into early Monday, before 
high pressure briefly builds in again Monday night. Tuesday and 
Tuesday night, an area of low pressure will move into south 
central Canada, while a second passes to the south of our area as 
it moves offshore. A new low will form to our north as these two 
lows weaken then combine with each other. This low will strengthen 
to our north Thursday through Saturday. 


&& 


Near term /until 6 am Sunday morning/... 
low pressure just east of the Canadian Maritimes will continue to 
move offshore and depart tonight. Meanwhile, surface high pressure 
over the Tennessee/Ohio valleys will build east. Pressure gradient over the 
area will relax through this evening, and winds drop off fairly 
quickly to 5-10 miles per hour this evening. After midnight, winds diminish 
even further to 5 miles per hour or less. 


Strato cumulus streaming in from the northwest will impact most of the western 
portions of the County Warning Area with broken-overcast skies at 4000-5000 feet for much of 
tonight. Otherwise, skies clear out. Going towards daybreak, skies 
become mainly clear. 


Temps this evening will slowly drop off, but it looks as if sometime 
between midnight and 6 am, skies should clear out enough and winds 
will diminish enough for strong radiational cooling conditions to 
develop. As a result, overnight lows will drop into the mid and 
upper 20s across the Poconos and northern NJ, and in the low 30s for 
most of NJ/PA. Temps along the urban corridor of I-95 and along the 
Atlantic coast, as well as the Delmarva, will drop into the mid 30s. 


&& 


Short term /6 am Sunday morning through 6 PM Sunday/... 
the center of the high will move towards the Delmarva by Sunday 
morning, and then throughout the day, will move offshore. Meanwhile, 
low pressure to the west will develop and organize as it presses 
east. Sunday will be dry with no precip, but will expect mid and 
high clouds to increase during the afternoon hours. 


Highs on Sunday will be a few degrees short of normal. 


&& 


Long term /Sunday night through Saturday/... 
the high pressure retreats northward early Sunday evening before a 
weak surface trough and associated mid/upper disturbance approach 
the area. Low-mid level moisture and lift will increase across the 
area as this disturbance moves across the area overnight into 
Monday morning. We expect precipitation chances to increase from 
the southwest after midnight and spread northeastward through the 
overnight into Monday morning. It could be cold enough for some 
snow or sleet to mix in for the southern half/two-thirds of the 
area while the northern third of the area may stay snow for the 
entire time, and have the best chance to see accumulating 
snowfall. Quantitative precipitation forecast amounts are relatively light, so we only expect 
around a half inch to one and a half inches at across the 
northern areas, with a little dusting elsewhere. 


As both the surface trough and the short mid/upper disturbance 
pass to our northeast during the day, precipitation chances will 
diminish by midday. Dry weather will then remain for the remainder 
of the afternoon and continue into Monday night as high pressure 
briefly builds across the area. 


This dry weather will only be temporary as the high pressure will 
be retreating during the afternoon ahead of an approaching storm 
system. An area of low pressure will be lifting through the 
northern Mississippi River valley and into south central Canada, 
while another will be moving across the Appalachians to our south. 
As the southern low lifts northward, we expect enhanced moisture 
and lift to spread across our area as several short waves aloft 
move across the area. Low clouds and precipitation chances will 
increase from south to north late in the day into the evening, and 
continue during the overnight. 


By Wednesday morning, the southern low will have moved offshore and 
will be east of the area. However, we may still be under the 
influence of a surface trough associated with this low through the 
day wedensday into Wednesday night. As a couple of short 
wave/vorticity impulses slide across the area, we could continue to 
have low clouds and precipitation affect the area. 


By early Thursday, the low pressure across southern Canada and 
the low offshore weaken. They then combine to our north during the 
day Thursday into Thursday night, before strengthening and slowly 
lifting northward Friday into Saturday. A strong west to 
northwest flow will develop across the area. With steep lapse 
rates across the northern portions of the area and enhanced low- 
mid level moisture forecast to remain, especially across the 
northern portions of the area and farther north, we could continue 
to see snow or rain showers Thursday through Friday, and possibly 
continue into Saturday. 


One thing for sure for the end of the week, regardless of 
precipitation, is it will get cold and windy for the latter 
portion of Thursday, but especially Friday and Saturday. Wind 
chills will likely get into the single digits to lower teens for 
many areas overnight each morning Thursday night through Saturday 
morning when the temperatures are the lowest. 


&& 


Aviation /02z Sunday through Thursday/... 
the following discussion is for kphl, kpne, kttn, kabe, krdg, 
kilg, kmiv, kacy and surrounding areas. 


VFR conditions with broken-overcast ceilings at 4000-5000 feet through this 
evening. Ceilings will scatter out late tonight. Few clouds at 4000- 
5000 feet expected Sunday morning. 


Surface winds 15-20 knots with 20-30 knots gusts will diminish quickly 
this evening to less than 10 kt, and then winds diminish to 5 knots or 
less late tonight. West-northwest winds increase to 5-8 knots Sunday morning. 


Outlook... 


Sunday night-Monday...VFR early, becoming MVFR or IFR overnight and 
continuing into Monday. Snow possible for the northern half/two- 
thirds of the area, with rain for the southern areas. Precipitation 
ends by midday, but clouds likely to linger through the day. 


Monday night...conditions may improve to VFR for a period 
overnight. 


Tuesday-Wednesday...conditions lowering to MVFR/IFR during the 
morning with periods of rain/fog/drizzle likely. Snow also 
possible for northern areas. Winds likely become gusty 15-20 
knots out of the northwest late in the day. 


Wednesday night...steady rain likely ends during the evening, but 
lower clouds may linger into the night. Gusty northwest winds 20-25 
knots possible. 


Thursday...generally VFR, but scattered showers are possible during 
the day which may temporarily lower conditions. Gusty northwest 
winds 25-30 knots. 


&& 


Marine... 
Small Craft Advisory conditions will continue on the ocean waters through 06z. 
Tranquil conditions then expected through Sunday as high pressure 
builds in from the west. 


Sunday night-Tuesday...sub-Small Craft Advisory conditions expected. 


Tuesday night-Wednesday...Small Craft Advisory winds likely, with 
conditions approaching gale force. 


Wednesday night...winds likely drop below advisory levels, but seas 
could remain above 5 feet. 


Thursday...northwest winds increase to Small Craft Advisory levels 
during the day. 


&& 


Phi watches/warnings/advisories... 
PA...none. 
New Jersey...none. 
Delaware...none. 
Maryland...none. 
Marine...Small Craft Advisory until 1 am EST Sunday for anz450>455. 


&& 


$$ 
Synopsis...Robertson 
near term...mps/nrr 
short term...mps 
long term...Robertson 
aviation...Robertson/mps 
marine...Robertson/mps 



National Weather Service Glossary of Abbreviations
Back to forecast page
Non-Expanded Version (with abbreviations)

Units: English | Metric

Find the Weather for any City, State or Zipcode, or Country:

U.S. State List | Severe Weather | Tropical Storms | Ski Conditions
United States | Canada | Central America | South America | Asia | Europe | Australia | Africa | Islands

Weather Underground

© Copyright 2016
The Weather Company, LLC