Scientific Forecaster Discussion
fxus61 kokx 260540
Area forecast discussion
National Weather Service New York New York
140 am EDT Mon Jun 26 2017
a weak cold front moving across this morning will be followed by
another one later today. A cold front crosses the region
Tuesday afternoon with high pressure building to the south of
the region for Wednesday. A warm front crosses the region late
Thursday followed by warm, humid and unsettled weather on Friday
though the weekend.
Near term /until 6 am this morning/...
a weak cold front has shifted winds to the northwest and dropped
temperatures several degrees with its passage. There have been
some gusty winds to accompany the passage as well but expect
these to be relatively brief.
Showers in vicinity of frontal boundary and relatively higher
dewpoints, mainly across eastern Long Island and into adjacent
waters, with otherwise a dry overnight expected. The forcing
for these showers can be attributed to the shortwave and
associated positive vorticity advection aloft which will have
the most intense portion pass to the east of the region by early
The cold front moves across by this morning with all locations
at that point expected to have northwest flow and lower dewpoints.
Lows were kept nearly the same as previous forecast, with a
range from the lower 50s to upper 60s.
Short term /6 am this morning through 6 PM Tuesday/...
another weak surface trough develops over the area Monday.
Aloft, heights fall to the west of the area as next shortwave
moves across the Great Lakes region.
Plenty of sunshine Monday morning, gives way to a some
afternoon clouds especially north and west of NYC. A few
isolated showers will again be possible across the interior.
Dry conditions are expected Monday night.
Temperatures on Monday will climb into the 70s and lower 80s.
Monday night, lows fall into the 50s and 60s.
Long term /Tuesday night through Sunday/...
looks fairly dry with comfortable humidity and slightly below normal
temperatures through mid week. A warm front approaches on Thursday
as low pressure passes across southern Canada. In its wake, a cold
front sags south into New York state on Friday. The front becomes
stationary near the region into the weekend - which appears will be
Upper trough axis approaches Tuesday, passing Tuesday night. Perhaps
a tad more instability Tuesday and trof/pseudo cold frontal passage triggers a
showers and perhaps a ts (instability is limited with dry mid
Wednesday is dry and then warm advection starts in on Thursday.
Frontal boundary in the region, or just north, on Friday and have
pops in for thunderstorms and rain. Looks to remain unsettled through the Holiday
weekend at this time. Li's as low as -5 c with long narrow cape's
and pwat's over 2 inches in a unidirectional flow supports
potential for flash flooding - mainly in urban areas.
Temps come back to near seasonable on Thursday and then go above
Friday into the weekend. No heat issues foreseen though.
Aviation /05z Monday through Friday/...
VFR through the taf period with high pressure south of the
Winds will continue to become west-northwest-northwest overnight. A brief period
of winds 10-15 kt with a few gusts around 20 kt remain possible,
but these should quickly diminish in the next hour or so with
winds becoming 10 kt or less thereafter.
Winds gradually back to the SW on Monday. Afternoon sea breeze
development backs winds to the south at coastal terminals, 10 to
15 kt. There is a lower probability of a sea breeze at kewr and
kteb with winds more likely staying SW-SSW.
Outlook for 06z Tuesday through Friday...
Monday night...VFR. Slight chance of an eve shower northwest of NYC
Tuesday...mainly VFR. Chance of a late day shower/tstm.
Thursday...mainly VFR. Chance of a late day shower/tstm mainly
north of the NYC metros and Long Island.
Friday...mainly VFR. Chance of a late day shower/tstm.
winds and seas will remain below small craft levels through
Monday night. Ocean seas will likely build to Small Craft Advisory criteria late
Thursday and continue as such into Friday.
no hydrologic impacts expected through Thursday. There is potential
for localized flash flooding associated with Summer convection
Friday through the weekend - mainly in urban areas. River flooding
is not anticipated.
astronomical tides are still running high with potentially
another round of isolated minor coastal flooding for the South
Shore back bays, which could be seen with the high tides
tonight (approximately between 10pm and 12am). The water levels
would only be expected to touch the minor benchmarks, again for
just a few gages in the South Shore bays.
observations from kfrg (farmingdale, ny) are not available.
Observations from khpn (white plains ny) and khvn (new Haven ct)
are being disseminated through backup methods. All is due to
an FAA communication line outage. Return to service time is
short term...British Columbia