Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Mount Holly New Jersey
333 PM EST Tuesday Nov 24 2015
high pressure will strengthen as it builds over the northeastern
United States through Wednesday, cresting to the south of
Newfoundland late Thursday or Friday. A cold front is expected to
arrive from the northwest on Saturday with high pressure following
for Sunday. Low pressure will build across the midwestern United
States bringing increasing moisture to the region early next week.
Near term /until 6 am Wednesday morning/...
a middle level trough extended from Quebec to the waters off New
England this afternoon. The feature will continue to progress to the
east. Meanwhile, surface high pressure will strengthen as it builds
across the northeastern states tonight. The center of the high is
forecast to reach Maine around daybreak on Wednesday.
Some moisture is expected to linger around the 4000 to 6000 foot
level into this evening over parts of eastern Pennsylvania and
northern New Jersey. As a result, we will continue to forecast some
clouds there. Otherwise, a mostly clear sky is anticipated for
tonight with perhaps a little cirrus building down from the Great
A west to northwest surface wind around 5 to 10 miles per hour into this
evening should become light and variable at most locations for
tonight. The nearly ideal radiating conditions are expected to allow
temperatures to drop into the range from the middle 20s to the lower
Short term /6 am Wednesday morning through 6 PM Wednesday/...
a middle level ridge from the west is forecast to build over our region
on Wednesday with its axis expected to pass overhead late in the
day. The center of the strong surface high is anticipated to move
eastward from Maine to the waters off Nova Scotia.
The circulation around the high should cause a light easterly
surface flow to develop in our region. The sky will likely remain
mostly clear and temperatures are expected to be right around normal
for the 25th of November. Maximum readings are anticipated to range
from the lower 40s in the elevated terrain of the Poconos and
northwestern New Jersey to the lower and middle 50s on the coastal
Long term /Wednesday night through Tuesday/...
the high pressure system influencing our weather will shift off to
our north and east with the ridge axis cresting across the region
late Wednesday. The high will continue to influence our weather
through Friday as the south to southeast flow will keep warmer
temperatures across the region. Temperatures for both days will be
well above normal ranging from the 50s across the north to middle 60s
across the south.
With the high shifting eastward, the flow across the region becomes
more easterly and we will see an increase in moisture across the
region. With low level moisture increasing, we may see some patchy
fog develop Wednesday night into Thursday morning and again
Thursday night into Friday morning.
A cold front will cross the region on Saturday. Not a ton of
moisture with the front but there looks to be enough for some
showers to occur. Precipitations looks to be fairly light and if the
GFS has a say, we won't see much precipitation, if any, at all. With
the earlier arrival of the front, the cold air will filter in
through the daytime leading to cooler temperatures as the day GOES on. Maximum
temperatures across the northern areas will likely occur earlier in the day
as a result. Overnight lows will be much colder than the previous
night with lows dropping into the upper 20s to upper 30s across the
High pressure will return briefly for Sunday but it appears to be
fairly weak and quickly is pushed out of the way by low pressure
moving into the midwestern states. However, the models are not in
agreement as to just how strong the high is and also how much
moisture will be ushered in by the low to our west. For now, we will
maintain a cloudy forecast with a chance for some showers for late
Sunday and Monday. With colder air in place, especially during the
nighttime hours, there will be a chance for some snow showers across
portions of the forecast area. A stronger low pressure system may
approach the region around midweek.
Aviation /21z Tuesday through Sunday/...
the following discussion is for kphl, kpne, kttn, kabe, krdg, kilg,
kmiv, kacy and surrounding areas.
VFR conditions are expected through the taf period with mainly
scattered stratocumulus into this evening, then a mostly clear sky
for tonight into Wednesday.
A west wind around 6 to 10 knots this afternoon should diminish to
light and variable for tonight. A light easterly wind is anticipated
to develop on Wednesday.
Wednesday night through Friday...mainly VFR conditions expected.
Patchy fog during the overnight into early morning hours is
possible. Low clouds are possible mainly late Thursday and Friday.
Friday night and Saturday...a cold front will cross the
region Saturday with MVFR/IFR conditions possible. Clearing from
northwest to southeast and return to VFR later in the day.
Sunday...mainly VFR conditions expected. A slight chance for some
showers, mainly across the southern terminals.
high pressure is forecast to build across the coastal waters of New
Jersey and Delaware for tonight with its center reaching the waters
off Nova Scotia late on Wednesday.
A west wind is expected to veer gradually to the north this evening,
then to the east on Wednesday. Speeds are anticipated to remain
generally less than 15 knots. Wave heights on our ocean waters
should be around 2 to 3 feet. Waves on Delaware Bay are forecast to
be 2 feet or less.
Wednesday night through Thursday night...sub-advisory conditions
Friday and Saturday...increasing waves on the ocean may build to
around 5 to 7 feet. North to northwest winds may gust up around
25 knots later on Saturday.
Sunday...winds and waves are expected to fall below Small Craft
Advisory criteria early with a period of sub-advisory conditions
the following locations may experience near record warmth Friday
November 27, presuming there is considerable sunshine from midday-
early afternoon Onward with a south to southwest wind of around 10
miles per hour. Note the 00z/24 European model (ecmwf) and its MOS continues much warmer
Friday than the 00z/24 GFS MOS and we have a forecast that favors
the warmer European model (ecmwf). It does look to be quite a nice day!
Record highs for Friday November 27
kabe 62 -1988 and 1959
krdg 65- 2011
kmpo 60- 2006 and 1984
kacy 69- 1981
November as a whole is projecting to be a top 10 warmest month
for at least portions, if not all of our forecast area.
We will reevaluate any changes with respect to overall rank in
our Wednesday morning afd ~ 430 am, which will be based on climate
data through Tuesday and any adjustments to 24 hour maximum/mins
issued in our 330 am Wednesday forecast package.