Scientific Forecaster Discussion
fxus61 kakq 200221
Area forecast discussion
National Weather Service Wakefield Virginia
921 PM EST Fri Jan 19 2018
high pressure lingers across the deep south tonight...then
slides off the southeast coast through the weekend. A cold
front crosses the region Tuesday morning.
Near term /until 6 am Saturday morning/...
sky clear as high pressure to the south dominates. Lwrd temps in a few
places based on ltst obs. Lows in the 20s to nr 30 at the beaches.
Short term /6 am Saturday morning through Monday/...
surface high pressure will prevail through the weekend with
mostly clear/sunny and dry conditions. The initial high will
slide off the southeast coast Saturday. A subtle trough slides
across the northeast Saturday night with a weak backdoor
boundary sliding across the ern shore. High-res models
indicating potential for some developing low stratus/patchy fog
possible toward morning across the Piedmont. High pressure then
rebuilds across the mid-Atlantic Sunday. Models a bit slower
with the upper trough through Tuesday...and thus expect a dry
day Monday, and into Monday night, as the upper trough lifts
across the Great Lakes. The airmass will continue to modify
through the period, with highs ranging from the mid 50s to near
60f inland/Piedmont, and in the low/mid 50s for the ern shore
and coastal southeast Virginia/NE NC. Lows Saturday night will generally be
Long term /Monday night through Friday/...
a storm system tracking across the southern Great Lakes by Monday
will push its attendant cold front across the local area during
Tuesday. What remains to be seen is whether this occurs during the
morning or afternoon as there's about a 6-hr difference in timing
between the 12z operational GFS and European model (ecmwf). The 12z gefs tends to
side more with the ECMWF, and so am inclined to think the fropa
will be during the midday or afternoon hours at this time. Have
high chc to likely pops for most of the area during the 06z-18z
Tue period, then pcpn moving out of the entire area by 00z Wed.
The remainder of the week should be dry.
Lows Mon night mainly in the low/mid 40s. Highs Tue in the low 50s
on the ern shore to the 55-62 elsewhere. Lows Tue night in the low/
mid 30s. Highs Wed in the mid 40s on the ern shore to the upr 40s to
mid 50s elsewhere. Lows Wed night from the upr 20s north-northwest to the
low/mid 30s southeast. Highs ranging through the 40s on Thu, then mid 40s
to mid 50s on Fri.
Aviation /02z Saturday through Wednesday/...
VFR conditions continue through the forecast period as high
pressure to the south dominates. Light SW wind tonight incrs
to arnd 10 kts Sat.
high pressure settles off the southeast coast Sunday and Monday with
clear and dry conditions continuing. A cold front crosses the
region Monday night bringing a chc of showers. High pressure
returns later Tuesday.
high pressure will dominate the weather pattern over the marine area
through the weekend with sub-sca conditions continuing. Light S-SW
winds through this evening will increase to 10-15 kt overnight and
Saturday. Winds diminish again by late Sat, becoming north-northwest for a time
Sat night and Sunday morning. S-SW around 10 kt then prevail again
by Monday. Waves 1-2 ft; seas 2-3 ft. A cold front approaches the
region from the west Monday night then crosses the water on Tuesday.
There are some timing issues that still need to be worked out
amongst the models with respect to whether the front passes first
thing in the morning or in the afternoon. Either way, expect Small Craft Advisory
conditions to be possible Tuesday with the fropa.