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fxus61 kakq 231809 

Area forecast discussion
National Weather Service Wakefield Virginia
109 PM EST Thu Feb 23 2017

high pressure remains well offshore today into tonight as low
pressure slides off the Florida Peninsula. A strong cold front
approaches from the west Friday into Friday night, and crosses
the local area late Saturday. High pressure returns Sunday.


Near term /until 6 PM this evening/...
latest sfc analysis indicating sfc low pressure off the East
Coast of Florida, with an inverted sfc trough extending north-northeast up
to the NC coast. Split flow aloft making for relatively light
winds/weak steering flow aloft. Very warm today with readings
already mainly in the 60s to around 70 f as of 16z/11 am under
variably cloudy skies (still lingering mostly cloudy over the
far southeast closest to the surface trough offshore). Fairly
high dew pts in the mid-upper 50s and a light southerly flow
suggest potential for some developing cumulus inland with skies
to avg partly sunny for the aftn. Based on current conditions,
raised highs a degree or two over inland zones with mid 70s
common and a chance for upper 70s. Closer to the coast, highs
will avg in the 70-75 range.


Short term /6 PM this evening through Saturday/...
expect dry weather and a mild night tngt (lows in the 50s) with
high pres staying offshore and low pres passing well south of
the local area. With decent low-level moisture and light winds,
could see some patchy fog develop.

Conditions Fri will be similar to those of today, with southerly
flow and temps climbing into the 70s areawide under a partly
cloudy sky with no pcpn. Again see climate section below for the
day's records.

More interesting scenario shapes up then for Sat as a cold
front and potent mid-level shortwave trough approach from the
west then cross the area late in the day. Not much chance of
rain in the morng (20-40% chance limited to the Piedmont/west
of i95), then pops range from 20-30% NE NC to 60% near/north of
ric after noon. Included chance of thunder as well due to
decent instability and forcing. Storm Prediction Center has the northern half of the
forecast area in a marginal risk for severe thunderstorms in association
with a Low Cape/high shear environment. Main threat would be
damaging wind gusts, but attm there is uncertainty over coverage
of convection. High temps Sat mainly in the low/mid 70s.


Long term /Saturday night through Wednesday/...
cold front slips off the coast Sat evening...W/ drying/gusty
west-northwest winds and temperatures returning to near normal (beginning
sun). Sfc hi pres drifts over the forecast area Sun night...resulting in
mainly sky clear and chilly conditions. Quick moving low pressure
tracks from the Ohio Valley Mon across the forecast area Mon night W/
increasing cloudiness and low pops (15-25%). Another warm up
begins Tue and continues through Wed as sfc hi pres sets up off
the coast...and return S flow develops. Dry and mild Tue...a
warm front lifting through the forecast area Tue night may clip the region
W/ clouds and low pops (10-20%). Breezy/warm Wed ahead of
approaching cold front from the west. Models push that front
through the region late Wed (possibly accompanied by scattered rash).

Lows Sat night in the u30s northwest to the l40s southeast. Highs sun in the
M-u50s. Lows Sun night from the l30s north and west to the u30s-around
40f southeast. Highs Mon in the u50s-around 60f on the Eastern Shore
to the 60s elsewhere. Lows Mon night in the u30s northwest to the m40s
southeast. Highs Tue again in the u50s-around 60f on the Eastern Shore
to the 60s elsewhere. Highs Wed in the 60s on the Eastern Shore
to the 70s elsewhere.


Aviation /18z Thursday through Tuesday/...
scattered cumulus (~4000 ft) has developed this afternoon mainly
over inland portions of the area in response to light southerly flow
and seasonably high dewpoints. Any cu should dissipate later this
evening. Otherwise, VFR conditions are expected to continue through
the afternoon and evening as high pressure builds over the region.
Winds will average 8-10 kts out of the S/southeast this afternoon with some
higher gusts at sby, winds diminish after sunset.

Still expecting fog development tonight, mainly after 06z, due to
mainly clear skies and high dewpoints. Included IFR/MVFR
visibilities at all taf sites tonight due to fog potential. Would
not be surprised to see some locally dense fog, especially away from
the coast. Fog is expected to dissipate generally after 12z and we
will return to VFR conditions. Winds will remain light out of the southeast
to S tonight through Friday afternoon.

Outlook: besides early morning fog and stratus, expect mainly VFR
conditions through early Saturday. Showers and thunderstorms are
expected to develop with a cold front Saturday afternoon and into
early evening. Dry/VFR conditions return for Sunday as surface high
pressure builds into the region. Winds will be gusty out of the west-northwest
at times on Sunday. Sub-VFR conditions will once again be possible
late Monday and into Tuesday as a low pressure system approaches
from the west. &&

high pressure will remained centered well off the mid-Atlantic
coast through Friday as low pressure meanders off the Florida coast,
and nrn stream energy remains well north of the region from the
Great Lakes through the Saint Lawrence Valley. High pressure
will slide farther offshore Friday night into Saturday as a cold
front pushes from the Ohio Valley Friday night and ewd across
the mountains Saturday. Meanwhile, the srn stream low will
gradually lift newd well off the southeast coast. A south-southeast wind
will remain aob 15kt through Friday night, and may increase a
few kt Saturday due to a tightening pressure gradient, but
should still remain sub-sca. Seas will generally be 2-3ft
through Friday, before increasing to 3- 4ft Friday night into
Saturday as long period swell arrives from the low offshore.
Waves in the Bay will average 1-2ft. The cold front will cross
the coast Saturday night followed by modest cold air advection and strong
pressure rises. Scas are likely Saturday night into Sunday
morning with a northwest wind reaching 20-25kt with gusts to 30kt and
4-6ft seas/3-4ft waves. The wind diminishes Sunday afternoon as
high pressure builds into the region. High pressure quickly
pushes offshore Sunday night into Monday with the wind becoming


Feb 2017 is shaping up to rank among the warmest on record
given continued warmth over the next week. Daily record highs
are listed below for today-Sat, with the top 3 warmest
february's on record listed below that. Expecting ric, orf to be
the 2ns warmest, ecg to be at least into the top 3 warmest. Sby
looks on track to be 4th or 5th warmest.

Daily record highs for today 2/23, Friday 2/24 and Saturday 2/25:

2/23 2/24 2/25

Ric 75 in 1985 82 in 1985 83 in 1930
orf 79 in 1975 82 in 2012 81 in 1930
sby 74 in 1943 77 in 2012 80 in 1930
ecg 77 in 1975 79 in 1985 77 in 1985

Warmest february's on record (average temps):

* ric: (most likely finish for 2017: 2nd warmest)
* 1) 49.9 (1890)
* 2) 48.5 (1976)
* 3) 48.1 (1884)

* orf: (most likely finish for 2017: 2nd warmest)
* 1) 52.4 (1890)
* 2) 50.5 (1909)
* 3) 50.1 (1990)

* sby: (most likely finish for 2017: 4th warmest)
* 1) 46.1 (1976)
* 2) 45.8 (1984)
* 3) 45.7 (1925)

* ecg: (most likely finish for 2017: 3rd warmest)
* 1) 52.1 (1990)
* 2) 51.8 (1939)
* 3) 50.3 (1976)


Akq watches/warnings/advisories...


near term...lkb/mas
short term...mas

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