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Area forecast discussion
National Weather Service Wakefield Virginia
539 PM EST Sat Feb 25 2017

Synopsis...
a cold front exits this evening. High pressure and more seasonal
conditions return Sunday and Monday. A warm front and associated
surface low pressure track across the area Monday night into
Tuesday.

&&

Near term /until 6 am Sunday morning/...
update at 530 PM...a Severe Thunderstorm Watch continues for
far eastern portions of Virginia and the Virginia/Maryland Eastern Shore until 800
PM this evening. Strong wind gusts and hail threat continues.
The surface cold front will exit the coast between 700-800 PM
and severe weather will come to an end. Adjusted precip forecast
accordingly to line up better with ongoing conditions.

Previous discussion (135 pm)...
sfc cold front located just west of the County Warning Area as of 1230 PM this
afternoon. Although convection in far SW Virginia waned this morning,
a line of thunderstorms is redeveloping along the front due to
daytime sfc heating. Current enhancement is terrain- induced,
however it shouldn't take much to keep this line going through
the rest of today based on strong, unidirectional west winds
through the atmospheric column. Thunderstorms will likely remain
within organized line segments with strong wind gusts being the
primary threat today. Some storms may quickly become severe
with damaging winds and possibly a quick burst of large hail (1
inch or larger in diameter). Pwats have come up to around 1
inch, therefore the threat for very heavy rainfall and localized
flooding is low. Pinpointing exactly where the strongest storms
will occur will be a challenge, since the best dynamics lie northwest
of the Richmond Metro area to the Maryland lower Eastern Shore and
best differential heating/instability lies across sern areas of
the forecast area. Storm Prediction Center has the entire local forecast area within
a slight risk for severe storms today, which means that
scattered severe thunderstorms are possible. Please stay aware
of rapidly changing conditions and take shelter inside when
threatening weather approaches/occurs.

The sfc cold front and subsequent thunderstorms will quickly
push eastward the rest of the afternoon into early evening...
exiting the coast between 700-900 PM tonight. Gusty south winds
ahead of the front/thunderstorms will quickly become west-northwest behind
the frontal passage and remain breezy through most of tonight...
especially at the immediate coast where gusts should average
20-30 miles per hour. Dewpoints will fall faster than temperatures due to
the well- mixed environment, thus making the ambient air feel
cooler than the actual temperature. Either way, temps will drop
into the low-mid 30s northwest to upper 30s to around 40f southeast by morning
with skies becoming mostly clear by midnight.

&&

Short term /6 am Sunday morning through Tuesday/...
sfc high pressure builds across the southeast states Sunday, up
along the southeast Virginia coast Sunday night, and then moving well off the
mid Atlantic coast on Monday. A warm front then lifts north into
the region late Monday night into Tuesday. Conditions will be
dry and more seasonal on Sunday with mostly sunny skies and
breezy west winds during the afternoon (especially across the
Maryland/Virginia eastern shore). Highs in the lower 50s inland (mid-upper
40s nrn neck and Maryland/Virginia eastern shore). Winds decouple Sunday
night with light south winds but the area remains somewhat
wedged in the cooler airmass. Lows generally in the lower 30s
inland (mid- upper 30s immediate coast). Clouds increase late
Sunday night into Monday as the sfc high moves offshore and
shortwave moisture/energy begins streaming into the region from
the southwest. Forecast remains dry on Monday with temperatures
generally warming into the lower 60s (generally upper 50s far
nrn counties and Maryland/Virginia eastern shore). The aforementioned warm
front lifts north into the area late Monday night into Tuesday
with continued partly to mostly cloudy skies and more
substantial warm air advection taking place. Expect lows well
above normal with readings in the upper 40s to around 50 northwest to
lower 50s southeast. Highs will also be around 15 degrees above normal
with readings in the lower 70s along/south of Interstate 64 and
mid-upper 60s north of this line. Increasing chances for light
rain showers Monday night into Tuesday should also be
anticipated as isentropic lift (especially invof the warm front)
will enhance precip chances in persistent SW flow aloft with
shortwave energy/moisture streaming across the region.

&&

Long term /Tuesday night through Saturday/...
sfc high pressure will remain anchored well off the southeast coast
Tuesday night into Wednesday with broad S-SW flow across the
local area. Meanwhile, an upper trough digs across the
plains/Midwest with sfc low pressure making its way into lower
Michigan by 00z Thu. The low the lifts NE into/thru New England
thru Wed night/Thursday with its attendant cold front sweeping
thru the local area Thursday morning. Expecting an increase in
pops across the northwest counties Wed aftn (30-50%), then high chance
to likely pops areawide Wed night (40-60%). Chc pops (30-50%)
linger into Thursday, especially in the morning across southeast areas
while drying out from northwest to southeast thru the rest of the day. Warm
Wednesday with highs in the 70s. Behind the cold front, cooler
temps are set to arrive next Thu-Sat. Highs Thursday in the 50s
to low 60s. Highs Friday/Saturday in the 40s to low 50s. A quick
moving system may bring another chance of pcpn on Friday.

&&

Aviation /00z Sunday through Thursday/...
a cold front with an associated broken line of showers and
thunderstorms will cross the region later this afternoon allowing
for a period of sub-VFR conditions at all sites. Showers/storms will
enter the region mainly after 19z and move east across the area,
departing offshore after 00z. Winds could gust in excess of 50 knots
with the strongest storms. High pressure builds into the region
behind the front Saturday night allowing for a return to VFR
conditions. Gusty northwest winds will be possible behind the front,
especially near the coast and at sby, tonight and into early Sunday.

Outlook: high pressure slides offshore Sunday night into Monday,
followed by weak low pressure Monday night and into Tuesday. This
will bring a chance of rain to the region and the next chance for
sub-VFR conditions. Another cold front will approach the region from
the west on Wednesday.

&&

Marine...
convection ahead of a quick moving cold front will affect the
marine area between 3pm-8pm. Winds will be south 10 to 20 kt
this aftn in advance of the front, generally remaining sub-sca,
although locally stronger gusts are possible with tstms into the
early evening. Seas are currently running 4-5 ft, and will
increase to 4-6 ft all ocean zones late today into tonight with
the frontal passage. Waves in the ches Bay will increase to 2-4
ft. The cold front will move off the coast this evening/early
tonight followed by modest cold air advection and strong pressure rises. Northwest
winds will average 15-25 kt with gusts to 30 kt and 4-6 ft
seas/3-4 ft waves into Sun morning. Am concerned about brief
strong/gusty winds with the frontal passage this evening as
winds shift to the northwest quickly. Will handle this potential with
special marine warnings as necessary. Small Craft Advisory flags are in effect
thru late tonight for the ches Bay, sound and rivers. Small Craft Advisory flags
are in effect for the coastal waters thru Sun morning. The wind
diminishes sun aftn as high pressure builds into the region.
High pressure quickly pushes offshore Sun night into Mon with
the wind becoming S.

&&

Climate...
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 and Sat, with the top 3 warmest
february's on record listed below that. Expecting ric, orf to be
the 2nd warmest and ecg to be at least into the top 3 warmest. Sby
looks on track to be 4th or 5th warmest.

Daily record highs for Saturday 2/25:

2/25
----------
ric 83 in 1930
orf 81 in 1930
sby 80 in 1930
ecg 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...
Maryland...none.
NC...none.
Virginia...none.
Marine...Small Craft Advisory until 4 am EST Sunday for anz635>638.
Small Craft Advisory until 6 am EST Sunday for anz630>634.
Small Craft Advisory until noon EST Sunday for anz650-652-654-
656-658.

&&

$$
Synopsis...bmd
near term...bmd
short term...bmd

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