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fxus61 kokx 230803 
afdokx

Area forecast discussion
National Weather Service New York New York
403 am EDT Thu Mar 23 2017

Synopsis...
high pressure builds today, and passes to the east tonight. A
warm front moves across the region Friday. The warm front
north of the region Friday night and Saturday will move back
southwestward Saturday night into Sunday. A weak low develops
along the front and the low and front eventually move east of
the region by Monday night and Tuesday of next week. Another
cold front approaches for next Wednesday.

&&

Near term /until 6 PM this evening/...
the center of high pressure builds to our west, and passes to the
south this afternoon. Upper trough tracks further to the east.

A dry, chilly day is expected, with lighter northwest winds than what was
observed yesterday. A few gusts are possible in the northwest flow, but
winds will diminish this afternoon and back to the west as the high
tracks south.

Temperatures, after a cold start to the day, will rebound through
the 30s, but will peak about 10 degrees below normal, upper 30s to
lower 40s.

Plenty of sunshine is expected.

&&

Short term /6 PM this evening through 6 PM Friday/...
upper ridge to the west flattens tonight and Friday as closed low
moves across the mid section of the country. Surface high pressure
passes east of the area.

A warm front then approaches Friday morning, with a weak shortwave
riding along the top of the ridge, passing across the area Friday.

Winds remain light tonight as they become variable or light S/SW.
With cold airmass in place, temperatures will fall into the 20s
and 30s as high clouds increase. Some locations may radiate
into the teens. Still quite cold.

Increasing moisture riding over the top of the flattening ridge will
approach Friday morning. Light precip associated with warm air
advection is anticipated. Expect a brief period of light
precipitation to push through, with higher coverage northwest zones, and
less southeast zones per model consensus.

As for ptype, this could be problematic. Depending on when precip
moves in, looks like shortly after 12z, a wintry mix is possible.
Snow, sleet and freezing rain is a good bet, especially away from
the coast. Again, depending on precip onset.

Temps near the coast should be warm enough for plain rain. Quantitative precipitation forecast
should be under a tenth of an inch, so this is not a big event. But,
slick travel is possible as sfc/Road temps may be cold enough for
some light icing.

&&

Long term /Friday night through Wednesday/...
mid levels transition from zonal flow Friday night through Saturday
night to ridging Sunday, which will be followed by an approaching
shortwave on the back end of the ridge. The axis of this trough
moves across on Monday. Behind this shortwave, more quasi-zonal flow
will be established. There will be a larger shortwave approaching
from the northwest for the middle of next week.

At the surface, Friday night through Saturday will be when the
region is in the warm sector. The warm front will be north of the
region. Then, the front will start to shift southwestward, coming
back through the region as a back door cold front Sunday. The front
will stay west of the region and high pressure will stay well east
of the region going through Sunday evening. For late Sunday night,
the front will slide back east with weak low pressure developing
along it. The weak low and front stay near the region Monday and
finally move east of the region Monday night and Tuesday. Another
cold front approaches for the middle of next week.

Overall, an unsettled weather pattern sets up leading to less
diurnal temperature range as the airmass becomes more maritime from
an increasing easterly flow with rounds of light to perhaps moderate
rain at times.

Temperatures are warmest on Saturday with area in the warm sector as
highs are forecast to range from the low 50s to low 60s. Sunday
looks to be the coolest day in the long term with a back door cold
front moving in as highs that day range from the low to mid 40s.
Lows at night through the long term are pretty consistent, in the
upper 30s to low 30s for a majority of the area.

&&

Aviation /08z Thursday through Monday/...
VFR through the taf period with a mainly clear sky.

Northwest winds 15-20kt with gusts 25kt will slowly diminish overnight.
Gusts may die off for a short period for most terminals, with
the exception of the NYC terminals. Winds will pick up again
for a few hours late morning and early afternoon Thursday, then
likely drop off in the evening as high pressure settles across
the area.

Clouds increase late in the taf period as low pressure passes north
of the region.

..NY Metro enhanced aviation weather support...

Detailed information, including hourly taf wind component forecasts,
can be found at: http://www.Weather.Gov/zny/n90

Kjfk taf comments: occasional gusts may be higher than forecast.

Klga taf comments: occasional gusts may be higher than forecast.

Kewr taf comments: occasional gusts may be higher than forecast.

The afternoon kewr haze potential forecast is green...which implies
slant range visibility 7sm or greater outside of cloud.

Kteb taf comments: occasional gusts may be higher than forecast.

Khpn taf comments: occasional gusts may be higher than forecast.

Kisp taf comments: occasional gusts may be higher than forecast.

Outlook for 06z Friday through Monday...
Thursday night...VFR with winds becoming light.
Friday...MVFR possible. Chance of rain showers. SW winds g25kt.
Saturday...mainly VFR. Chance of mid-late afternoon MVFR in
cigs and -shra.
Saturday night and Sunday...MVFR/IFR conds in rain. East-southeast winds
g20-25kt.
Monday...MVFR conds possible in showers.

&&

Marine...
as high pressure builds toward the waters this morning, then south
of the waters later today, winds will continue to diminish. Seas
subside as well. Small Craft Advisory remains up for the ocean waters this
morning.

The winds shift around to the west, then southwest tonight as the
high moves east. As the pressure gradient tightens Friday, expect SW
winds to increase, and Small Craft Advisory conditions are likely during the
afternoon, with gusts 25 to 30 knots. Seas, per guidance, will
build once again.

Small Craft Advisory chances are higher Friday night as well as late Saturday night
through Sunday night, mostly on the ocean. Otherwise sub Small Craft Advisory
conditions on other waters and other time periods for the marine
long term period covering Friday night through Monday.

Ocean seas with wave heights are forecast to stay in Small Craft Advisory range
Friday night into Saturday morning. Then the ocean seas are forecast
to get below Small Craft Advisory criteria Saturday afternoon through Saturday
evening before returning to Small Craft Advisory range late Saturday night through
Sunday and perhaps even into early Monday.

&&

Hydrology...
unsettled weather from this weekend through early next week may
result in an inch or more of precipitation. However, this would
occur over a prolonged period and would be intermittent, so no
hydrologic concerns are anticipated. Snowpack melt in interior
sections will continue at a slow rate through Thursday with
most areas likely loosing any significant snowpack by Saturday
as temperatures rise to above normal readings and lows even
remain above freezing.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until 11 am EDT this morning for anz350-
353-355.

&&

$$
Synopsis...jm/pw
near term...precipitable water
short term...precipitable water

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