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000 
FXUS61 KAKQ 220956
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
456 AM EST Fri Nov 22 2019

.SYNOPSIS...
High pressure centered along the Carolina coast moves offshore
tonight. A cold front enters the region late Friday and lingers
through Saturday before a strong low pressure system pulls the 
front off the coast by Sunday. High pressure returns late Sunday
into Monday.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
As of 115 AM EST Thursday...

Clouds have moved into the area with isolated light rain 
showers as a warm front across the northern most areas (mainly
north of the Potomac River and Delmarva. Radar is showing rain 
move across Delmarva tonight but expecting much rain to reach 
the ground since the air is relatively dry early on tonight. 
However, with the relatively drier air, not expecting much of 
the precip to reach the ground tonight. Mostly cloudy skies will
remain through the night tonight. A south wind has increased 
tonight, bring north moist air and warmer temperatures. 
Temperature tonight have likely already reach their minimum and 
have begun to climb since this evening. Most areas are in the 
upper 40s to low 50s at 1am. Not expecting temperatures to 
change much for the remainder of the night.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
As of 500 AM EST Friday...

A potent northern stream upper shortwave/sfc low will be 
tracking ewd from Ontario to Quebec today. As it does so, the 
trailing cold front will be approaching the region from the NW, 
reaching nrn portions of the CWA by late aftn-early evening. 
Deeper moisture (along with a series of weak disturbances) moves
in from the W-WSW during the day on Fri. NAM and HRRR show a
broad areas of light rain moving across central VA to central
Delmarva this afternoon main. While only the HRRR show the 
potential for scattered showers across SE VA/NE NC along the
cold front later this afternoon and into this evening. Given 
increasing confidence, have raised PoPs to ~70% from the NW 
Piedmont to the VA Nrn Neck/Middle Peninsula to the Lower MD 
Ern Shore for a 3-6 hr period, with likely PoPs over the entire
RIC Metro. Have PoPs of 30-50% across far srn VA and most of 
Hampton Roads, with only 20-30% PoPs for NE NC (mainly from 18z 
Fri-00z Sat). QPF amounts on Fri look light (mainly 0.10-0.20").
Forecast highs are mainly in the mid-upper 50s over the nrn 
two-thirds of the CWA, with low-mid 60s across srn VA/NE NC. 
Rain chances diminish and shift S from 21-00z Fri.

The front crosses most of the region Fri night, before
stalling just S of the VA-NC border in response to developing
sfc low pressure hanging back over the lower MS Valley. This
happens at the same time the closed upper low now over the SW
CONUS becomes centered over the Plains and continues to slowly 
move eastward. Expect some drying behind the front Fri night, 
with a slight chc PoPs for light rain across srn VA/NE NC 
through 03z Fri. Mostly cloudy across NE NC with clear to partly
cloudy skies across eastern VA and Delmarva. Lows range from 
the low-mid 30s across northern half of the area to the low 40s 
across coastal SE VA/NE NC.

The aforementioned surface low is progged to move eastward 
towards the Ohio Valley on Saturday. The stalled boundary will 
move back N as a warm front and will try to cross our region 
during the day on Saturday, but will remain south of our area
for most of the day on Saturday. Not a whole lot of changes to 
the forecast, GFS/ECMWF/NAM continue to be slightly slower w/ 
the arrival of the pcpn during the day on Sat (NAM/NAM Nest are 
slightly faster). Regardless, most areas will be dry Sat 
morning, but still mostly cloudy except over the eastern shore 
and NE zones where some sunshine is expected until midday. Rain 
will quickly move into the VA Piedmont by later Saturday 
morning, then overspread the I-95 corridor by 1pm Saturday. The 
steady rain will then reach Delmarva/Hampton Roads/NE NC by 7pm 
with much of the area covered by a shield of rain then. Note 
that this is a slower solution than previous runs of the models.
As for temperatures, expect a cold day (especially in areas N 
of the VA/NC border). Temperatures on during the day on Saturday
will remain mostly steady across the area. The NAM is the most 
aggressive with the CAD, but models are in good agreement that 
temperatures will remain cold throughout Saturday. Temperatures 
will slowly rise out of the mid-30s/upper-30s to the low-40s 
/mid-40s shortly after sunrise ahead of the rain. Once the rain 
begin, temperatures will likely drop a few degrees back into the
upper 30s to near 40 and remain until Saturday evening. 
Forecast highs are in the low 40s across the NW Piedmont, mid- 
40s across the I-95 corridor/Peninsulas/Delmarva, upper 40s 
across Hampton Roads/inland NE NC, and low 50s across coastal NE
NC. Models continue to depict highest chance for widespread 
moderate rainfall to be Sat night so have ~80 to 90% PoPs across
the entire area. In addition, models are showing some elevated 
instability (MUCAPE of 100-300 J/kg) moving across much of our 
area during the Sat evening- early Sun AM timeframe. Cannot rule
out a rumble of thunder or two during this time (best chc 
across the sern two- thirds of the CWA), but left any mention of
thunder out of the forecast for now. The warm front will slowly
move N through the first part of Sat night (as the sfc low 
tracks to our N). As a result, expect a non-diurnal temperature 
trend starting Sat evening. Temperatures are expected to quickly
warm after 7pm Saturday across SE VA, NE NC, and eastern 
Delmarva. Temperatures will climb into the upper 50s for NE NC, 
mid 50s from VA Beach to Williamsburg, and low 50s for Salisbury
and Ocean City. The warm front will likely not make it much 
farther NW than I-85 and the eastern side of the Richmond metro.
Temperatures across the Richmond metro will range from low 40s 
west to near 50 on the east side of the metro between 10pm-2am. 
Temperatures then fall during the latter half of Sat night as 
the cold front crosses the region from NW to SE. Lows Sun AM 
range from the mid 30s NW to the upper 40s/lower 50s across far 
SE VA/NE NC. Rain chances end in all areas by 12z Sun as the low
quickly moves offshore. Skies eventually become partly- mostly 
sunny by Sun aftn as weak high pressure builds toward the 
region. Highs mainly in the 50s on Sun. 

The high pressure will be centered near the area Sunday night 
which is will to temperatures dropping to near freezing inland (outside
of the urban areas) Monday morning. While, lows will be in the 
mid-upper 30s in the metros and along the coast. High pressure 
will remain over the area on Monday with highs in the mid-upper
50s.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 330 PM EST Thursday...

The beginning of the week starts off dry as high pressure will be in 
control. On Monday the high will be centered over the FL panhandle 
and by Tuesday the high will drift NE off the Mid-Atlantic coast. 
This will result in a W/SW flow for Monday and a S/SW flow for 
Tuesday. Temps on Monday will remain several degrees below normal 
with low temps ranging from the low 30s NW to upper 30s SE, and high 
temps in the mid to upper 50s. The southerly flow on Tuesday will 
bring temps up to seasonal norms with high temps in the upper 50s to 
lower 60s.

A cold front associated with a low pressure system that will drift 
from the great lakes region to northern New England will cross the 
area on Wednesday into Wednesday night. There won't be much moisture 
at all out ahead of the front, so just chance pops in for Wednesday. 
Rainfall amounts will be minimal, with most guidance suggesting less 
than a tenth of an inch. Since the front likely won't cross the area 
until later in the day, temps on Wednesday will remain warm, with 
low temps Wednesday morning in the 40s and high temps in the lower 
60s. After the frontal passage, high pressure builds in for Thursday 
resulting in dry and slightly cooler conditions.

&&

.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
As of 130 AM EST Friday...

Mainly BKN skies tonight with CIGs of 10-15k feet. Winds have 
already turned southerly and will increase through the day on 
Friday to 10-15 kt with gusts 20-22 kt between 17z- 22z before 
decreasing to 10 kt afterwards. Light rain showers will move 
across the area Friday afternoon (Pop 50-70%). The probability 
of SHRAs is lower across the southeastern terminals, therefore 
SHRA was kept out for all sites except KSBY. MVFR conditions are
likely for KSBY Friday afternoon with the rain showers. Brief 
MVFR conditions are also possible across SE VA/NE NC by Fri 
evening as the line of heavier showers moves across the region.
The front will drop south of the VA/NC border by 00z. Skies 
will begin to clear behind the front, with clear to SCT skies by
03z Saturday.

OUTLOOK...VFR conditions late Fri night into mid- afternoon Sat
with winds shifting to N/NE after the cold FROPA by Sat 
morning. Low pressure approaches from the SW on Sat before 
tracking across the region Sat night. Rain is likely, as well as
flight restrictions during the Sat aftn-Sat night timeframe 
(due to both CIGS/VSBYS). VFR/drying out for Sun with a breezy 
W/NW wind.

&&

.MARINE...
As of 250 AM EST Friday... 

Latest obs reflect SSW flow 10-15 kt over the waters this
morning. ~1020mb Sfc high pressure is offshore of the Mid- 
Atlantic/southeast coast early this morning, with low pressure 
sliding across southern Ontario/Quebec, with the associated cold
front approaching the region from the west.

Winds are gradually increasing this morning, as the pressure 
gradient tightens between the departing high pressure and 
approaching low pressure system to the north. SSW winds to
~20-25 kt with gusts to ~30 knots over the ocean zones are 
still expected later this morning, before steadily ramping down 
with slackening gradient through this afternoon and tonight. 
Small Craft Advisories continue over the Bay/Sound and Coastal 
waters through mid-aftn, and for coastal waters north of Cape 
Charles through early evening. Have also added SCA for lower 
James River through 17z, again with thought that gusts diminish 
through the aftn.

Seas 3-4ft this morning will build to 4 to 5 feet by mid-morning 
(perhaps up to 6 feet out 20 nm), and waves in the Bay to 2 to 3
feet. Seas may remain elevated to 5 feet into tonight, especially
across the north/out 20 nm. 

Secondary surge of CAA may bring a brief increase in winds this
evening, but expect winds to quickly drop off overnight and
through Sat. Calmer conditions (regarding the winds), during 
the day Saturday with a light E to SE flow ahead of the next 
system.

That system will track east of the Appalachian Mountains and 
across the Carolinas Saturday evening, then across our area 
Saturday night into early Sunday morning. Winds become southerly
late Saturday as the low tracks across VA and MD. The area of 
low pressure tracks off the Mid Atlantic coast Saturday night- 
Sunday turning winds to the WNW and increasing wind speeds to 15
to 25 knots by Sunday morning. Another round of SCAs will 
likely be needed on Sunday across the Bay and coastal zones. 
Seas increase again to 4 to 6 feet, and waves in the Bay around 
2 to 3 feet. Calmer conditions take hold late Sunday into early 
next week.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory until 4 PM EST this afternoon for ANZ632-
     634.
     Small Craft Advisory until 4 PM EST this afternoon for ANZ633-
     656-658.
     Small Craft Advisory until 1 PM EST this afternoon for ANZ630-
     631-638.
     Small Craft Advisory until 7 PM EST this evening for ANZ650-
     652-654.

&&

$$
SYNOPSIS...ERI/LKB
NEAR TERM...CP/ERI

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