Scientific Forecaster Discussion
Area forecast discussion
National Weather Service New York New York
654 am EDT Sat Sep 5 2015
high pressure remains in control through the middle of next
week...with a cold front approaching late in the week.
Near term /until 6 PM this evening/...
upper ridging continues to build overhead today. While at the
surface...Canadian high pressure builds south over the region and
maintains a seasonably warm and dry Canadian maritime airmass over
the region. East/NE winds could be a bit gusty this morning...gradually
veering southeast this afternoon. Patchy stratus this morning expected to
gradually mix out...with only few-scattered after cumulus. Limited mixing in
this airmass should keep highs near seasonable...upper 70s/lower
The 4-6 feet east-northeast wave direction this morning will likely result in
more of a longshore sweep...and generally a moderate rip current
risk. The exception will be potential high rip risk on east side
of groins...jetties and piers due to interaction with the
longshore sweep. Wind and wind waves are expected to veer a bit
more to the east/east-southeast this afternoon...but will also be subsiding.
These wind waves will likely result in a 2 to 4 feet surf at the
Short term /6 PM this evening through 6 PM Sunday/...
upper ridging remains overhead...with center of high pressure
slowly sliding east-southeast of the region.
Good radiational cooling conds and Canadian airmass in place should
allow for temperatures across rural areas to fall into the 50s. Elsewhere
Mostly sunny and dry Sunday expected. A developing return flow
and warm air advection should allow for temperatures to begin moderating. Limited mixing
should keep temperatures in the the lower 80s to 85. Afternoon coastal
seabreeze development expected.
Long term /Sunday night through Friday/...
gradually increasing drought and fire weather concerns through
Models in good agreement with NE upper ridging gradually flattening
through midweek...but region continuing to be under control of broad
western Atlantic ridging. There also continues to be depiction of a
broad and weak upper low over the southeast US...part of which may shear NE
early this week. Predictability on the evolution of this feature is
low...with low probability of any sensible weather impacts.
Otherwise...general agreement on the western Atlantic ridging
weakening enough during middle to late week to allow for more active
westerlies to begin impinging on the NE. Timing and strength of
approaching shortwave energies continue to be in question.
Dry and very warm to hot conditions are expected early to middle next
week as high pressure sinks southeast of the region and eventually merges
with Bermuda high. Highs expected to generally run 5 to 10 degrees
above seasonable through the early week period. Generally upper 80s
to lower 90s...with heat indices at this point looking just near or
slightly higher than temperatures.
If ridging breaks down as depicted...allowing for more active
westerlies to work towards the region during the middle to late
week...this would allow a cold front to approach the
region...bringing potential for unsettled weather late week into the
weekend. Run to run model consistency has been poor on the
details...but there seems to be some agreement on a front
approaching the region late Wednesday or Thursday...then lingering near the
region...until it can be pushed through the region by stronger
shortwave energy during the weekend. Confidence on daily details in
this part of the forecast is low at this point...but potential
exists for some wetting rainfall.
Aviation /12z Saturday through Wednesday/...
high pressure remains in place today.
VFR. NE winds 10kt or less veering southeast around 10kt with sea
breezes early afternoon. Winds becoming light and variable tonight into
early Sun morning.
Outlook for 12z Sunday through Wednesday...
Small Craft Advisory remains in effect on the ocean waters through
this morning...primarily due to seas. Winds and seas should
subside as the morning progresses.
Sub Small Craft Advisory conditions then prevail across all waters through the
rest of the forecast period with a relatively weak pressure
gradient in place. A gust or two 20-25kt will be possible
Tuesday/Wednesday afternoons/early evenings west of Point Lookout with sea
kbdi values between 500 and 700 and 1 hour fuels moisture of 5 to 8
percent are expected today. East/NE wind gusts into the teens are
expected this morning...decreasing and becoming southeast this afternoon.
Relative humidity values will drop into the 30s this afternoon.
no widespread significant rainfall is forecast through the middle
of next week...allowing drought conditions to continue to
develop/worsen region wide. Northeastern New Jersey...Long Island and
southern CT are currently experiencing moderate drought conditions.
Marine...Small Craft Advisory until noon EDT today for anz350-353-355.