000
FXUS61 KOKX 261120
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
720 AM EDT Fri Apr 26 2024
.SYNOPSIS...
Strong high pressure remains over the region into Saturday, moving
off shore as a warm front approaches. The warm front moves through
the region late Saturday into early Sunday morning. A weakening
cold front passes to the north Sunday as high pressure builds to
the south. A cold front approaches Tuesday and moves across the
region Tuesday night. A series of frontal systems may pass
through the area late next week.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
The freeze warnings and frost advisories remain in effect
through 12Z as temperatures varied from the upper 20s to the
lower 30s.
Updated for current conditions.
Northern stream upper trough over eastern Canada into the
northeast moves slowly eastward through today as a building
ridge approaches to the west. Meanwhile strong high pressure
remains over the area. While the airmass will be modifying high
temperatures will still be around 5 degrees below normal.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
The building upper ridge approaches tonight with the axis moving
into the region Saturday. With an Omega blocking pattern setting
up the ridge will remain in the area through Sunday. With
surface high pressure over the region tonight winds become
light. However, the airmass continues to modify with weak warm
advection that begins late today continuing into tonight. Some
high cloudiness will also be moving into the ridge. Temperatures
tonight remain above freezing, however, patchy to areas of frost
are possible. Frost advisories may be issued later today for
areas where more widespread frost is expected.
A surface and upper low pass well to the west as the upper ridge
remains Saturday as a surface warm front moves through the
region late in the day and into Sunday morning. There will be
some weak lift with the front, and limited moisture. There may
be scattered showers with the frontal passage, and will have
chance probabilities. Then later Sunday a cold front moves to
the north and weakens with the ridge in place. Will keep Sunday
dry at this time, however, a few showers may develop across the
far north regions late in the day with some instability in the
area. With the airmass continuing to modify temperatures will
be near normal Saturday night and near to a few degrees above
Sunday.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
*Key Points*
*Mainly dry conditions expected with a few chances of showers
each afternoon Tuesday through Thursday.
*Confidence is increasing in a warming trend with above normal
temperatures likely through late next week. The warmest day of the
period looks to be on Monday.
There has not been much change to the forecast thinking with this
update and have stuck close to the NBM with a few exceptions on the
temperatures. Decent model agreement to start the period with an
amplifying ridge and anomalously warm air mass (2-3 stdev above
normal per NAEFS) in place and surface high pressure to the south.
Dry conditions locally as a result, and with 850mb temperatures
approaching 13-14C, low to mid 80s are a good bet for the interior on
Monday. In fact, NBM probabilities of >80F have been on the increase
the past few cycles, and are now as high as 80% from NYC north and
west. Onshore flow will keep the coastal areas a good 10 degrees
cooler, with SSTs still in the upper 40s to near 50. Record highs
across the area are in the upper 80s and lower 90s (Central Park is
89F, from 1974) so we look to be below any records at this point.
By Tuesday into Wednesday, the upper flow begins to flatten as the
ridge axis moves east of the region. Clouds will be on the increase
for Tuesday, which may help moderate temperates a bit as a weak
front heads through the area. Showers and possibly a thunderstorm
especially N/W of NYC for Tuesday afternoon, with some very marginal
surface based instability. This trend continues for Wednesday and
possibly on Thursday, as an upper low traversing the Great Lakes
region sends upper energy through the northeast. Some elevated
instability with a weak frontal passage on Wednesday. Shower chances
continue in the afternoon, but have kept thunder mention out of the
forecast for now.
For late in the week, there is model agreement on an upper low
ejecting out of the Northern Plains Thursday into Friday. This will
keep the shower chances going Thursday afternoon into Friday, though
have capped chances at slight for now. Under weak westerly flow,
there is significant spread the high temperatures for Thursday. For
instance, NBM interquartile range spreads from 72 to 86F for KEWR
and 70 to 83 for KSWF with the deterministic forecast near the 50th
percentile. For this update, have trended toward the NBM 75th
percentile for highs on Thursday, given the usual NBM cool bias
under westerly flow this time of year for NE NJ. If cloud cover
progression can hold off until later on Thursday, the upper end of
the NBM spread may be realized.
&&
.AVIATION /11Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
VFR. High pressure remains near the terminals through the TAF
period.
Winds increase this morning to 5-10 kts out of the SE. Winds
eventually veer south, then west-southwest this evening before
becoming light and vrb into the overnight.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled AMD expected.
OUTLOOK FOR 12Z SATURDAY THROUGH TUESDAY...
Friday night: VFR.
Saturday and Sunday: Mainly VFR. Slight chance of a shower Sat
night into early Sunday morning.
Monday: VFR.
Tuesday: MVFR or lower possible in afternoon showers and
possible thunderstorms.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
With high pressure in control into Saturday, and a warm front
approaching late Saturday into early Sunday morning, winds and
seas will remain below SCA levels across the forecast waters.
Warmer air moving over the colder ocean early next week could
develop fog, but it is much too early for any specific details
on timing and extent. Sub SCA conditions on all waters through
Tuesday under relatively weak flow.
&&
.HYDROLOGY...
No hydrologic concerns through the end of next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Freeze Warning until 8 AM EDT this morning for CTZ005>008-012.
Frost Advisory until 8 AM EDT this morning for CTZ009>011.
NY...Freeze Warning until 8 AM EDT this morning for NYZ067>070-079-
081.
Frost Advisory until 8 AM EDT this morning for NYZ078-080.
NJ...Freeze Warning until 8 AM EDT this morning for NJZ002.
Frost Advisory until 8 AM EDT this morning for NJZ004-103-105-
107.
MARINE...None.
&&
$$
SYNOPSIS...DBR/MET
NEAR TERM...MET
SHORT TERM...MET
LONG TERM...DBR
AVIATION...DBR
MARINE...DBR/MET
HYDROLOGY...DBR/MET