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Area forecast discussion 
National Weather Service Wakefield Virginia
951 PM EDT Friday Jul 29 2016

Synopsis...
a weak frontal boundary will linger over the area through
Saturday. Meanwhile, a trough of low pressure will become centered
across the eastern states this weekend into early next week.

&&

Near term /until 6 am Saturday morning/...
richmond's run of 90+ high temps ended at 7 days today, with a
high of 87. Norfolk continues as the high reached 90. Cooler
temps were thanks to modest height falls, light north to northwest
winds and a good amount of cloud cover. Radar depicts an echo free
forecast area. Upper trough currently over the Midwest tracks
eastward tonight as the frontal boundary over the northern mid-
Atlantic region begins to slowly drop southward. Cloud cover
increases from the west as the disturbance approaches. Expect the
overnight period to remain dry, but will introduce slight chance
pops late tonight for the northwest Piedmont. Not as mild as the
past several nights, but still in the low to mid 70's.

&&

Short term /6 am Saturday morning through Monday/...
for this weekend...a broad trough of low pressure currently over
the Midwest will slide east and take up residence over the eastern
conus. Mainly diurnally driven showers and thunderstorms will be
possible both days with pops in the 30-50% range. With the trough
in place will also see temps remain close to normal. Highs
Sat/sun from the mid/upr 80s north to the low 90s south. Lows Sat
night in the 70s.

The upper trough sharpens even further across the East Coast Sun
night into Monday helping to drive a cold front through the area
by midday Monday. Pcpn chances Mon will be greatest over the
southern half of the area, so will indicate chc pops (30%) there.
Slight chc pops elsewhere. Highs again from the upr 80s to low
90s.

&&

Long term /Monday night through Friday/...
a cold front stalls off the mid Atlantic coast into the
Carolinas Mon night through mid week...gradually washing
out as sfc high pressure builds into the NE Continental U.S. From the
Great Lakes region during the second half of the week. This
will keep a chance for thunderstorms in the forecast through
Tue night...with only a slight chance for storms across
far S-SW counties Wed/Thu closer to the remnant boundary.

With sfc high pressure building into New England early in
the week and then settling over the NE Continental U.S. During the
second half of the week...expect temperatures to be more
seasonal with highs generally in the mid-upper 80s and
cooler dewpoints in the upper 60s to lower 70s...effectively
squashing heat indices and limiting them to the lower 90
degree range. Onshore winds also develop by Tue aftn and are
expected to persist through the rest of the week...thus
enhancing any drying and cooling effects to temps, dewpoints,
and overall precip chances.

&&

Aviation /02z Saturday through Wednesday/...
finally, a quiet evening! There is nothing on the radar over the
County Warning Area and only a few clouds. Winds are light. Some patchy fog is
possible tonight especially for sby but would not be surprised at
some fog development at the other sites. However am not expecting
significant development.

Outlook...there is a better chance (40-50%) of shras/tstms both
days this weekend with a weak frontal boundary in the vicinity.
Periods of MVFR/IFR conditions are possible in any tstm.

&&

Marine...
NW-N winds averaging 5-10kt prevail this aftn with only a
slight chance for thunderstorms into this evening. Winds
become more NE tonight and then E on Sat as high pressure
builds across se Canada. Speeds will continue to average
5-10kt during this time. A front over NC tonight is
expected to lift north Sat into Sat night with the wind
becoming se 10-15kt. The front then settles over the
region sun into Mon and then slowly pushes off the coast
Mon night into Tue. High pressure returns to the waters
on Wed. There is a good chance for thunderstorms (30-40%)
each aftn/evening Sat through Tue...with a slight chance
for far srn coastal waters and Currituck Sound on Wed.
Seas will average 2-3ft through the period with 1-2ft waves
in the Bay.

&&

Akq watches/warnings/advisories...
Maryland...none.
NC...none.
Virginia...none.
Marine...none.

&&

$$
Synopsis...jdm
near term...jdm/Sam
short term...jdm
long term...bmd
aviation...mpr/jef
marine...ajz/bmd

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