Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Mount Holly New Jersey
343 am EDT Friday Aug 29 2014
high pressure will remain over the area today before sliding
offshore on Saturday. A warm front will move northward through our
region on Saturday as well. A cold front will approach the area
from the west on Monday and cross the region on Tuesday, with high
pressure building back in by Wednesday.
Near term /until 6 PM this evening/...
high pressure was located over southeastern Ontario early this
morning. The center of the high will progress to the east and it
should reach the New England coast late in the day.
We are anticipating a mostly sunny sky for today with some patches
of cirrus and a few afternoon cumulus.
The wind will start from the north around 4 to 8 miles per hour. The direction
is forecast to veer to the east then to the southeast as the center
of the high passes to our north.
The statistical guidance was similar with today's maximum
temperature forecasts. Highs should be near 80 at most locations
with readings not expected to get above the lower and middle 70s in
the elevated terrain up north. Dew points should be mainly in the
upper 40s and 50s.
Short term /6 PM this evening through 6 am Saturday/...
the center of the high is expected to drift farther off the New
England coast tonight. A light southeasterly surface flow is
anticipated in our region.
The sky is forecast to be mostly clear for tonight. However, with
the flow off the ocean and with an eventual slow increase in low
level moisture some patchy low clouds and light fog may develop
Minimum temperatures should be mostly in the 50s and lower 60s.
Long term /Saturday through Thursday/...
the period starts with surface high pressure to the NE and a large 500 mb
ridge over the area. As a result, Sat will be warm and dry, with
increasing humidity. A warm front will cross the region on Sat. As
southwesterly flow increases, Sunday will be hotter, even more humid, with
dew points in the 70s.
Several S/waves will begin to work their way across the region and
precipitation chances will increase on sun. However, each model has a
differing solution and confidence remains low on precipitation
coverage/placement. It appears the best chances still remain north and
west. The GFS is wettest, the European model (ecmwf) is similar but slower and a tad
drier. The CMC is essentially dry on Sunday and the NAM/WRF is
probably somewhere in the middle. So for now will carry low chance
probability of precipitation.
The NAM/WRF and CMC and to a lesser extend the GFS and European model (ecmwf) want
to make Sun night the wettest period. However precipitation placement is
still a big question with both the CMC and GFS keeping the bulk of
the precipitation to the of our area or over the northern extent.
The GFS is then fairly dry on Monday with some diurnal rain showers/thunderstorms and rain
late. The CMC is completely dry on Monday and the European model (ecmwf) is much
wetter late, but still implies its mostly later diurnal
shwrs/tsra. But solutions run from no precipitation to close to 1/4 inch. So
again confidence remains low and will carry low chance probability of precipitation.
Models have better agreement that once any diurnal activity ends,
Monday night should be dry.
Then precipitation chances increase again Tuesday afternoon/evening with cold front passage. Then high
pressure builds back in for Wednesday and Thursday marking a return to dry weather.
Temperatures will start near normal and then be above normal (close to 90
degrees) for many areas for much of the pd, before returning to near
normal by the end of the extendd period. Sat still looks to be the best
day of the Labor Day weekend Holiday.
Aviation /07z Friday through Tuesday/...
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 a mostly
A northerly wind around 3 to 7 knots early this morning should veer
toward the east and southeast for this afternoon and tonight.
Sat...mostly VFR. Localized fog early, generally at the more rural locations.
Sun...mostly VFR. Scattered rain showers/thunderstorms and rain mainly north and west of phl which
could lower cigs/vsbys. MDT confidence.
Monday through Tuesday...mostly VFR. Scattered rain showers/thunderstorms and rain possible everywhere
on Mon, with less potential Monday night and again Tuesday afternoon. Low
confidence on precipitation coverage.
no marine headlines are anticipated for today and tonight.
A northerly wind around 10 knots is expected to veer to the east and
southeast for this afternoon and tonight.
Wave heights on our ocean waters should be mainly 2 to 4 feet. Waves
on Delaware Bay are forecast to be 2 feet or less.
Sat through Tuesday...sub-sca conditions expected across our waters
with high pressure moving offshore on Sat. Increasing southwesterly flow
will occur as ridge builds ahead of a cold front which will approach
Monday into Tuesday. It is psbl, though confidence is low, that we could
reach marginal Small Craft Advisory criteria for a time later sun into Monday as seas
increase in the southwesterly flow. Seas will subside behind the frontal passage.
residual swells from Hurricane Cristobal will continue to affect the
coasts of Delaware and New Jersey for today. As a result, there is a
moderate risk for rip currents.