378
FXUS61 KOKX 270812
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
412 AM EDT Sun Oct 27 2024
.SYNOPSIS...
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High pressure builds over the area today. A weak frontal passage
early Monday allows high pressure to strengthen over the area
through Tuesday. Low pressure tracking across the Upper Midwest
Tuesday night sends a warm front across the area. The trailing
cold front over the Upper Mississippi Valley on Wednesday will
track east and through the area on Friday.-- End Changed Discussion --
&&
.NEAR TERM /THROUGH TONIGHT/...
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High pres builds in from the W today, with the center of the
high setting up S of LI by late in the day. This setup will
result in light NW winds this mrng becoming wly by aftn. IR
shows a batch of clouds over the cwa that will pass east of the
region this mrng, resulting in mostly sunny skies today. Temps
aob normal today with a cooler airmass in place. H85 temps blw
zero for the entire area.
A very weak backdoor front passes around 12Z Mon, producing a
wind shift to the N. Winds very lgt however generally 5kt or
less. The temp fcst for tngt is a challenge because of the
potential for mid and high clouds ahead of the front. As a
result, blended in some of the colder MET/MAV with the NBM to
compensate for the lgt winds, but did not go all the way because
of the cloud potential. Based on these fcst numbers, issued a
Freeze Watch for Orange county.-- End Changed Discussion --
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
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Dry and relatively cool on Mon, along with lgt winds, as a mid
1030s high builds in from the N.
Onshore sly flow develops by Mon ngt, with the potential for a
stratus deck developing around 3k ft. The NAM suggests lower
with chances for some light rain and dz from the low stratus on
Tue. The NAM llvl moisture is often overdone, so have held off
on pops for Tue attm. Did increase cloud cover abv the NBM on
Tue with the llvl moisture axis over the area in a warm frogen
regime.
Temps were the NBM with some local tweaks. The onshore flow on
Tue will result in noticeably higher humidity.-- End Changed Discussion --
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
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Global models remain in very good agreement in building an
anomalously strong upper ridge across the eastern third of the
country on Wednesday, and then shifting it offshore for the second
half of the week as an upper trough approaches from the Great Lakes.
The latter of which will send a cold front through the area on
Friday. The trend has been slower the last 24h for the cold frontal
passage.
At the onset of the period, low pressure tracking across the Upper
Midwest sends a warm front across the the area Tuesday night. There
is a low chance of showers in the warm advection preceding the
front. A deep-layered SW flow will bring very warm air into the
region for Wednesday and Thursday. 85H temps are still on target for
12-14C during this time. Highs and lows are forecast to be 10-15
degrees above normal at this time with temperatures approaching
record levels. The warmest day will be on Thursday where much of the
area is well into the 70s, and possibly 80 across NE NJ. As
mentioned yesterday, this remains a high confidence forecast. NBM
box and whisker plots show very little difference with the NBM 90th
percentile only slightly higher than the median (50th). The
deterministic is around the 75th percentile. There is more spread
heading into Friday with the cold frontal passage, which has trended
slower. There also remains a chance of showers late Thursday night
into Friday along and ahead of the cold front. This does not look
like a wet system at this time with less than a 0.25" of rainfall
from the 00Z globals.-- End Changed Discussion --
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
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High pressure builds across the area into Monday. A backdoor cold
front approaches from the north late tonight.
VFR. NW winds will gradually diminish and veer more northerly by
12Z, then back to the W by late morning/early afternoon. KJFK and
KBDR could see the winds for a time back to the WSW in the
afternoon. Light W winds tonight veer to the NW-N. Backdoor cold
front drops south along the New England coast. There is some
uncertainty as to how far west the front gets, but regardless a more
northerly flow will develop by 12Z Monday.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
KJFK could briefly go SW this afternoon.
OUTLOOK FOR 06Z MONDAY THROUGH THURSDAY...
Late Tonight-Monday: VFR.
Tuesday: VFR, but chance of MVFR east of the city terminals.
Wednesday: VFR. SW wind gusts 15-20 kt possible.
Thursday: VFR. SW wind gusts 20-25 kt possible.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
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SCA remains on the ocean til 6am, then all waters blw sca lvls
thru Mon. Sly winds increase on Tue with mrgnl sca winds
possible, particularly on the ocean.
A strengthening southerly flow midweek may build ocean seas toward 5
ft, and allow wind gusts to exceed 25 kt on Thursday.-- End Changed Discussion --
&&
.FIRE WEATHER...
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Dry weather continues today with RH near 20-30% across much of
the region. Winds will be light, near 5 to 10 mph. Given how
dry fuels and conditions remain, a Special Weather Statement was
issued for all land zones to highlight the continued risk of
wildfire spread, should ignition occur.
Afternoon RH values climb through early next week, between 30 and
40% Monday afternoon, increasing to over 50% by Tuesday. Coupled
with light winds, this should lower the risk of wildfire spread,
though dry conditions are expected to persist into late week.-- End Changed Discussion --
&&
.HYDROLOGY...
There are no hydrologic concerns through the period.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
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CT...Frost Advisory until 9 AM EDT this morning for CTZ005-006.
NY...Frost Advisory until 9 AM EDT this morning for NYZ067-068.
Freeze Watch from late tonight through Monday morning for
NYZ067.
NJ...Frost Advisory until 9 AM EDT this morning for NJZ002.
MARINE...Small Craft Advisory until 6 AM EDT early this morning for
ANZ350-353-355.-- End Changed Discussion --
&&
$$
SYNOPSIS...JMC/DW
NEAR TERM...JMC
SHORT TERM...JMC
LONG TERM...DW
AVIATION...DW
MARINE...JMC/DW
FIRE WEATHER...
HYDROLOGY...JMC/DW